Skip to main content

Full text of "Schlich's Manual of forestry"

See other formats


(Lite  B.  H.  Mtll  'JItbvary 


^!^   C 


^Torlh  Cnroima  State  (Hcik^e 

SD371 

S34 


SQ1 948788  P 


3D371 
334 


Qh^ 


59f}27 


¥^: 


This  BOOK  may  be  kept  out  TWO  WEEKS 
ONLY,  and  is  subject  to  a  fine  of  FIVE 
CENTS  a  day  thereafter.  It  is  due  on  the 
day  indicated  below: 


16No'46£ 


jui>«'   •-  3 


m 


SCHLICH'S 
MANUAL    OF    FOEESTEY 


FOREST  PEOTECTION. 


I.  ^ 


DR.    SCHLICH'S 

MANUAL  OF  FORESTEY. 

VOLUME  IV. 
FOKEST    PROTECTION, 

BY 

W.  R.  FISHER,  M.A.  Cantab,  et  Oxon., 

PAST    PRESIDK.NT,    ROVAL    KNOLISH   ARBORICULTUKAI,   .SOCIETV  ;    FORMERLY   CONSERVATOR  OF   FORESTS 
TO   THE   GOVERNMENT   OK   INDIA. 

WITH    300    ILLUSTRATIONS 

BEING 
AN     ENGLISH     ADAPTATION     OP 

'DER    FORSTSCHUTZ,"    by    DR.   RICHARD    HESS, 

PROFESSOR   OF   FORESTRY    AT   THE   UNIVERSITY    OF  OIESSEN. 

SECOND    EDITION. 


LONDON :     ' 
BEADBUEY,  AGNEW,  &  CO.  Ld.,  10,  BOUVEEIE    STEEET. 

1907. 


bradhurv,  agnew,  &  co.  ld.,  printers, 

LONDON    AND    TONBRIDGE. 


PREFACE  TO  THE  SECOND  EDITION. 


The  first  edition  of  my  translation  of  Dr.  Hess'  Forst- 
scHDTZ,  published  in  1895,  is  now  exhausted.  I  have  there- 
fore revised  it  and  have  increased  the  number  of  pages  from 
593  to  712,  and  the  number  of  plates  from  259  to  300.  I 
have  also  added  a  portrait  and  short  biography  of  Dr.  Hess, 
both  of  which  are  taken  from  a  biographical  sketch  written 
by  Forstmeister  F.  Kraetzl,  and  published  in  1902,  in  the 
53rd  annual  volume  of  "  Yerhandlungen  der  Forstwirte  von 
Mahren  und  Schlesien."  I  have  also  added  an  index,  although 
the  table  of  contents  appeared  to  me,  when  publishing  the 
first  edition,  as  a  suflicient  substitute. 

The  French  have  never  produced  .an  independent  work  on 
forest  protection,  but  have  included  the  subject  in  works 
on  silviculture,  entomology,  mycology,  &c. ;  the  rapid  sale, 
however,  of  my  first  edition  has  shown  that  English-speaking 
foresters  require  a  separate  treatise,  while  such  a  treatise  is 
part  of  the  scheme  of  Schlich's  Manual  of  Fokestry,  of 
which  this  book  forms  Volume  lY.  I  have  been  asked  why 
I  do  not  write  an  original  book  on  the  subject.  It  would 
have  been  impossible  to  do  so  without  borrowing  largely 
from  German  authors,  and  it  therefore  appears  preferable 
to  continue  my  former  plan  of  translating  the  best  German 
work  on  the,  subject. 

Most  of  the  additional  matter  contained  in  the  present 
volume,  as  compared  with  the  former  edition,  is  due  to 
additions  made  by  Dr.  Hess,  in  the  fourth  edition  of  his 
FoRSTScHUTz,  published  in  1900.  He  has  also  revised  the 
scientific  nomenclature  of  insects  and  fungi,  and  has  correct^ 


as  corrected, 

.59927 


VI  PREFACE    TO    THE    SECOND    EDITION. 

his  earlier  editions  wherever  the  advance  of  knowledge  rendered 
such  correction  necessary.  The  present  volume  is  not,  how- 
ever, merely  a  translation  of  Hess'  book  ;  I  have  added  matter 
that  I  considered  important  for  British  and  Indian  foresters, 
and  have  omitted  other  matter  as  being  only  of  local  interest. 
Several  of  the  new  plates  are  not  in  Hess'  book,  but  have 
been  inserted  as  illustrations  of  the  subject-matter,  and  also 
to  fill  otherwise  unsightly  gaps  at  the  ends  of  the  chapters. 

This  second  edition  of  Fokest  Protection  is  uniform  with 
the  third  edition  of  Volumes  I.,  II.  and  III.  of  the  Manual  of 
Forestry,  which  are  written  by  Dr.  Schlich.  It  will  very 
shortly  be  necessary  for  me  to  publish  a  second  edition  of 
Volume  v.,  Forest  Utilization,  as  that  book  is  also  nearly 
out  of  print. 

*W.  E.  FISPIER. 

B,  Linton  Road,  Oxford, 
January  \st,  1907. 


PREFACE  TO  FIRST  EDITION 


Dr.  W.  Schlich,  C.I.E.,  has  allowed  the  present  book  to  form 
Volume  IV.  of  his  Manual  of  Forestry.  For  this  favour  I  have 
therefore  to  thank  him,  as  well  as  for  the  kind  advice  and 
assistance  he  has  always  readily  afforded  me  during  the  progress 
of  the  work.  This  treatise  on  Forest  Protection,  the  full  scope 
of  which  is  explained  in  the  Introduction,  is  an  adaptation  for 
English  readers  of* the  well-known  German  Forstschutz,  by 
Dr.  Eichard  Hess,  Professor  of  Forestry  at  the  University  of 
Giessen,  in  Hesse  Darmstadt,  to  whom  I  am  most  grateful  for 
permission  to  utilize  his  book  and  its  illustrative  plates.  I 
have  found  it  at  times  necessary  to  deviate  from  the  original, 
especially  in  the  chapters  on  Forest  Offences  and  Eights  and 
Forest  Insects,  so  as  to  render  them  more  serviceable  for 
English  readers.  I  have  also,  wherever  practicable,  exemplified 
the  subject-matter  from  Britain  and  India,  so  that  the  book 
might  be  specially  useful  to  British  and  Indian  foresters. 

Mr.  B.  H.  Baden  Powell,  CLE.,  Instructor  in  Forest  Law  at 
the  Eoyal  Indian  Engineering  College,  and  late  Judge  of  the 
Chief  Court  of  the  Punjab,  has  very  kindly  revised  Chapters  HI. 
and  IV.  of  Part  L,  which  deal  with  Forest  Offences  and  Eights, 
and  has  rewritten  the  pages  on  forest  property  and  the  general 
account  of  forests  rights,  so  as  to  make  them  concordant  with 
English  law.  My  own  knowledge  of  insects  is  too  inadequate  to 
enable  me  to  deal  properly  with  Part  II.,  Chapters  IV.  to  VIII. , 
which  treat  of  Forest  Insects  ;  I  have  therefore  submitted  my 
translation  of  this  portion  of  the  Forstschutz  to  Mr.  W.  F.  H. 
Blandford,  F.Z.S.,  lecturer  on  Entomology  at  the  Eoyal  Indian 
Engineering  College,  and  I  here  express  my  great  obligation  to 


Viii  PREFACE    TO    FIRST    EDITION. 

him  for  revising  these  chapters  and  rewriting  many  pages  of 
them,  so  as  to  make  them  more  distinctly  applicable  to  British 
insects.  While  those  portions  of  the  work  of  Dr.  Hess  which 
deal  with  insects  unknown  in  the  British  Isles  have  been 
largely  abridged  or  entirely  omitted,  it  has  not  been  found 
possible  or  advisable  to  remodel  the  chapters  on  insects  from 
an  entirely  British  point  of  view.  The  scientific  names  of  the 
insects  referred  to  have  been  altered,  wherever  this  was 
required,  so  as  to  conform  with  the  nomenclature  adopted  in 
the  best  modern  systematic  works  on  British  entomology. 

Dr.  H.  Marshall  Ward,  F.E.S.,  has  very  kindly  looked  over 
Part  III.,  which  deals  with  forest  weeds  and  fungi,  in  which  he 
has  made  some  corrections.  The  scientific  names  of  the  forest 
weeds  follow  Hooker's  and  Bentham's  British  Flora,  1892, 
and  those  of  the  fungi,  E.  Hartig's  Lehrbuch  der  Baum- 
KRANKHEiTEN,  being  nearly  all  the  same  as  those  adopted  by 
Dr.  Hess. 

My  colleague  Dr.  F.  E.  Matthews,  F.I.C,  has  very  kindly 
assisted  me  wherever  any  special  knowledge  of  chemistry  was 
required,  as  in  the  last  chapter  dealing  with  the  effects  of  acid 
fumes  on  trees,  and  also  in  correcting  proofs  of  the  whole 
l)Ook.  I  have  to  thank  Mr.  J.  W.  Sowerby,  of  the  Botanic 
Gardens,  Eegent's  Park,  for  information  supplied  regarding 
the  effects  of  London  smoke  on  the  growth  of  trees. 

Due  reference  will  be  found  in  the  footnotes  to  the  authors 

whose  works  I  have  consulted. 

W.  E.  FISHEE. 

CooPKRS  Hill  College. 
May   1st,  1895. 


SHOET   BIOGKAPHICAL   NOTICE    OF 
DR.   RICHARD   HESS. 

PiiCHARD  Alexander  Hess  was  born  on  the  23rd  of  June, 
1835,  in  Gotha.  His  father,  Karl  August  Hess,  was  Privy 
Councillor  and  Member  of  the  Board  of  P»,evenue  at  Coburg, 
where  Hess  passed  his  early  youth.  In  1849,  his  father 
became  President  of  the  Board  of  Pievenue  at  Gotha,  and 
Hess  continued  his  studies  there.  After  leaving  school,  he 
was  at  first  inclined  to  a  military  career,  but  in  1854  decided 
to  become  a  forester  and  studied  practical  forestry  and  at  the 
same  time  entomology  and  botany  in  the  Georgental  Eevier, 
under  Oberforster,  afterwards  Forstrat,  Kellner,  and  Forst- 
meister  Schrodter,  both  distinguished  men.  In  1855 — 56, 
he  attended  the  Bavarian  forest  school  at  Aschaffenburg  out  of 
which  he  passed  first  among  thirty-four  candidates.  From 
1856  till  1858,  he  attended  classes  in  Law,  Finance,  and 
Natural  Science  at  Gottingen. 

He  entered  the  State  forest  service  of  Saxe-Coburg-Gotha  in 
1858,  and  was  appointed,  in  1859,  to  the  charge  of  the  forest 
range  Gehlberg,  in  the  Thliringer  Wald.  The  reigning  Duke 
was  extremely  fond  of  the  chase,  so  that  forestry  was  then 
subordinate  to  game-preserving  in  the  State  forests.  This 
subordination  of  forestry  to  game  induced  Hess  to  write  on 
the  subject  to  the  Forst-und-Jaf/dzeitunfj,  of  which  Dr.  Gustav 
Hess,  Professor  of  Forestry  at  Giessen,  was  then  editor. 
This  paper  was  not  published,  but  it  led  to  his  visiting 
Heyer  at  Giessen,  and  he  thus  formed  a  friendship  with  one 
of  the  most  distinguished  of  German  foresters. 

Heyer  made  him  French  correspondent  to  the  Forst-und 
Jugdzeitung,  and   he   translated  a  number  of  French  forest 


X  SHORT   BIOGRAPHICAL  NOTICE    OF    DR.    HESS. 

pamphlets  ("  Annales  forestieres,"  "  Revue  des  eaux  et  forets," 
&c.),  and  reviewed  several  important  French  works  on  forestry. 
]n  1868,  Heyer  was  appointed  Director  of  the  newly-established 
forest  school  at  Miinden,  and  Hess  succeeded  him  as  Director 
of  the  Giessen  forest  school  and  Professor  of  Forestry  there. 
This  post  he  has  held  ever  since,  although  he  was  nominated 
Professor  of  Forestry  at  Vienna  in  1877,  and  to  a  similar  post 
at  Munich  in  1884,  but  he  preferred  to  remain  at  Giessen. 

Hess  was  made  a  Privy  Councillor  in  Hesse  Darmstadt  in 
1890,  and  in  the  same  year,  his  portrait  and  a  sketch  of  his  career 
appeared  in  the  Golden  Book  of  the  German  people  among 
the  eleven  most  distinguished  German  foresters.  He  has 
published  several  works,  which  give  a  true  picture  of  his  mind, 
intelligent,  clear  and  true.  The  best-known  among  these 
are  :  "  Forstschutz,"  the  4th  edition  of  which  was  published  in 
1900,  of  which  the  present 'book  is  chiefly  a  translation; 
"Eigenschaften  und  forstiches  Verhalten  der  wigtigeren  in 
Deutschland  einheimischen  und  eingefuhrten  Holzarten " ; 
"  Encyclopiidie  und  Methodologie  der  Forstwissenschaft "  ;  a 
revision  of  the  4th  edition  of  Heyer's  "  Waldban  ".;  and  "  Die 
Forstbenutzung,"  a  second  edition  of  which  was  published  in 
1901. 

Hess  has  travelled  all  over  Germany  in  order  to  observe  the 
various  aspects  of  local  forestry,  also  in  Austria,  Bosnia  and 
Herzogovina.  He  is  one  of  the  most  popular  and  widest 
known  of  German  foresters,  and  English-speaking  people 
are  greatly  indebted  to  him  for  the  permission  he  has  so 
generously  accorded  for  a  translation  into  English  of  the 
results  of  his  long  experience  and  studies. 


TABLE  OF  CONTENTS. 

PAGE 
PKEFACE  TO  SECOND  EDITION v 

PREFACE  TO  FIRST  EDITION vii 

SHORT   BIOGRAPHICAL  NOTICE  OF    DR.   HESS  .     .       ix 

INTRODUCTION I 

PAKT   I. 
PEOTECTION  OF  FORESTS  AGAINST  MAN. 


CHAPTER  I. 
FOREST   BOUNDARIES. 

1.  The  various  kinds 10 

2.  Settlement U 

3.  Demarcation 12 

4.  Survey II' 

5.  Description 19 

C.  Legalisation 20 

7.  Upkeep 20 

8.  Cost 21 

9.  Improvement 21 

CHAPTER   II. 

PROTECTION   OF   FORESTS   AGAINST   IRREGULARITIES   IN 
UTILIZING   FOREST  PRODUCE. 

Section  I. — Pkincipal  Produce, 

1.  General  account    .  .        .     • 28 

2.  Overfelling  .         .      ' 23 

3.  Bad  felling 24 

4.  Careless  conversion 25 

.").  Bad  stacking 26 

6.  Careless  transport 20 


Xll  TABLE    OF   CONTENTS. 


PAGE 

Section  II. — Minor  Produce. 

1.  General  account 27 

2.  Bark 27 

3.  Turpentine,  resin,  and  gums 2S 

4.  Leaves  and  branches  of  forest  trees  .  .    •    .  .21) 

5.  Fruits  of  forest  trees  (collection) 3o 

(pannage) 31 

0.  Grass  and  herbage  (grass-cutting) 33 

„        (pasture) 35 

7.  Forest  litter 4'.i 

8.  Dead  branch-wood .">  1 

Ji.  Stones,  gravel,  sand,  kc 52 

10.  Other  protluce ."»3 

11.  Game  and  fisheries        .        .        .        .         .     ^    .        .        .        .     .  53 


CHAPTER    III. 

PROTECTION   OF   THE    FOREST   AGAINST   OFFENCES. 

1.  General  account 55 

2.  Definition  of  a  forest  offence 55 

3.  Classification  of  forest  offences 5t> 

4.  Protective  rules 59 


CHAPTER   IV. 
PROTECTION   AGAINST   FOREST    RIGHTS. 

Section  I. — General  View  of  Forests  as  '■  Estates  '   or  Piece.s 

OF  Property GI 

„       II. — General  Account  of  Forest  Rights  .     .  c>7 

„      III. — Special  Account  of  Forest  Rights     ....  78 


tablp:  of  contents.  xiii 

PAET   IL 
PEOTECTION  OF  THE  FOEEST  AGAINST  ANIMALS. 

PAGK 

Introductory  remarks Oo 


CHAPTER   I. 

PROTECTION   AGAINST    DEER   AND   WILD   PIGS. 

Six'Tiox  I. — General  Account 97 

II. — Red-deer  • 99 

III.— Fallow-deer 109 

IV.— Roe-deer .110 

V._WiLD  Pigs Ill 

CHAPTER    II, 

PROTECTION   AGAINST   RODENTS. 

Section  I.— General  Account 

,.         II.— Hares       .        .        .     * 

.,       III. — Rabbits  

IV.— Squirrels 

v.— Dormice 

VI.— Mice 

,,     VII.— Voles 

,,    VIII. — Beavers  and  Porcupines 

CHAPTER   III. 


114 
11.5 
116 
118 
122 
123 
121 
135 


PROTECTION   AGAINST  BIRDS. 

Section  I. — General  Account 136 

II. — Capercailzie  and  Grouse 138 

III.— Pigeons  and  Doves 139 

IV. — Jays  and  Nutcrackers 139 

v.— Finches  and  other  Small  Birds 140 

VI.— Woodpeckers 142 


XIV  TABLE    OF   CONTENTS. 

CHAPTER  IV. 
FOREST   INSECTS   (GENERAL   ACCOUNT). 

PAOE 

Section"  L— Classification 119 

II.— Distribution 153 

III.— Life-History 1,",5 

IV.— Number i:,9 

V.   -Useful  Forest  Insects 100 

VI.— Injurious  Forest  Insects ir.l 

1.  Damage  done .        .        .         .  ir.i 

2.  Preventive  rules  (Protection  nf  insoctivorous  birds,  itc.")               .     .  Idl 

3.  Remedial  measures 1 7:5 

4.  Treatment  of  injured  woods 178 

CHAPTER   V. 

INSECTS   USEFUL  TO    FORESTS   (SPECIAL  ACCOUNT). 

Okder     I. — Coleopteua 180 

1 1.— Hymenoptera 184 

111.— Diptera 194 

.,        IV.— Neueoptera    .        .        .^ 195 

,.         V. — Orthoptera  (Pseudoneuroptera) 197 

,.        VI.— Hemipteua lit? 

CHAPTER    VI. 

IN.IURIOUS   FOREST   INSECTS   (SPECIAL   ACCOUNT   OF 
C0LE0P7EJiA). 
Family  I.— Scarabaeidae. 

1.  Melolontha  rulf/arin  (Common  cockchaiov^ 199 

2.  M.  hipjHwastani 209 

3.  Rhi:otrogus  aohtltiulis  (Jnnc  chd.iQv') 210 

Family  II.— Ruprestidae. 

\.  Agriliin  riridix      .         .         .         .                  .         _         .         _         .     .  211 

2.  Other  species     .         .        .         .   ' 213 

Family  III.— Elateridae  (Click -beetles)   .        .        ...        .        .     .  214 

„       I  v.— Lym  i:.\v  Lf  )n  1  da  e. 

Lymcu.-i/lon  nuralc .                   .                   .         .          .         .         .         ,         .  21;> 


TABLE    OF   CONTENTS. 


XV 


Family  V,— Anobiidae. 
Xestohlum  teDselatum 


117 


Family  VI.— Curculioxidae  (Weevils). 

1.  Apoderus  coryli       ........         .         •  218 

2.  Rhynehites  hetulae 219 

3.  Strophosomus  coryli 220 

4.  Balan'mus  nucum  (Nut-weevil) 221 

5.  Orcliedes  fagi 221 

6.  0.  quercwt 223 

7.  Vryptorrhynchus  Japathi 223 

8.  Jlylohiua  ubietin  (Pine-weevil) 22.") 

9.  Pi-fnodex  notatus 233 

10.  Other  species 23.") 

Family  VII. — Scolytidae  (Bark-beetles). 


(") 
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
10. 


Subfamily  Tomicini. 
Tom icux  tyijoyraphvit 
T.  amitinus 
T.  chalcographux 
T.  gteiiographns  . 
T,  laricis 
T.  bidentatvs 
T.  acwuinatint 
T.  li/watvs  . 
T.  domestlnis  . 
T.  dixpar    . 


(V)  Subfamily  Hylesinini, 

1.  Ilyluiites  jxiUiatitx  .... 

//.  (iter 

Myclophiliix piniperda  (Pine-beetle) 
M.  minor    ..... 
Hylexinux fraxini  (Ash-bark  beetle) 


2. 
3. 
4. 
5. 
6.  If.  vittatm  . 


238 
246 
248 
2.50 
251 
253 
255 
255 


2G3 
2<;5 
271 
273 
275 


7.  If.  crenatm      ....        - 275 

(c)  Subfamily  Scolytini. 

1.  Scolytux  Geoff rogi  (Elm-bark  beetle) 277 

2.  S.  intricatns  ...........  278 


Fajiily  VIII.— Ceeambycidae  (Longicorns). 

1.  Stiperda  carcharias  (Large  poplar  longicorn) 


280 


2.  ,S.  popiilnea  (Small  poplar  longicorn) 282 

Family  IX.— Chrysomelidae  (Leaf -beetles). 

1.  ^7(ry.<(»H<'/a;wywZ;  (Red  poplar-leaf  beetle) 284 

2.  C.  vuUjatissima  (Willow-beetle) 285 


TABLK    OF   CONTENTS. 


CHAPTER   VIT. 
LEPIDOPTERA  {Jletemrrni,  Moths). 
Family  I.— Sesiidae.  page 

1.  iS2.s-<«a/r//'w/«/«  (Hornet  cleai'wing-motli)    ......  289 

Family  II.— Cossidae, 

1.  Cussns  ligniperda  (Goat-moth) 291 

2.  C.  aescnll  (Wood  leopard-moth) 293 

Family  III. — Bombycidae. 

1.  Gastropacha  jnnl  {Vmc-moih) 29-t 

2.  Bomhyx  neustria  (Lackey-moth) 302 

3.  B.  pud'ihuiKlti  (Pale  tussock  moth) .  304 

4.  ^.  r/(r//.s7(rr//m/ (Brown-tail  moth)     ....                   .     .  308 

5.  TJjxir'is  iiio/uicJiK  (Black-arches  or  Nun  moth)          ....  310 

Family  IV.— Noctuidae  (Night-moths). 

1.  A^uctiia  2}inij>erda  {Pine  noctuii) 320 

2.  J\\  ventAgialis 322 

3.  N.  aegetum  (Turnip  dart-moth) 325 

Family  V.— Geometridae  (Loopers). 

1.  6'eo?»e^7'«^/(w/a7'm  (Pine  looper-molli) 326 

2.  G.  brumata  (Winter-moth) 329 

Family  VI.— Tortricidae  (Leaf-roller  moths). 

1.  2/c/Z/«,«  r/(Z(»m«ff  (Green  willow  leaf -roller) 332 

2.  Tortrix  viridanu  (Oak-leaf  roller) 333 

3.  T.  hiioliana  (Pine-shoot  tortrix) 33.") 

4.  T.  turionana 338 

5.  T.  resinella 339 

6.  T.  rvjiinitrana ....  340 

7.  T.  2nnicolaiia 341 

Family  VII.— Tineidae. 

1.  Tinea  rariahilii  .         .         .         .         .         .         .         •         .         .     .  343 

2.  T.  curtisella  (Ash-twig  moths) 344 

3.  Coleoj)hora  larlcella  (Larch-miner  moth) 34r) 


CHAPTER  VIII. 

OTHER    OllDERS   OF   DESTRUCTIVE   INSECTS. 
{A)  Hymenoptera. 

Family  I.— Tenthredinidae  (Sawflies). 


Lophyrus  jnnl  (Pine  sawfly) 


350 


TABLE    OF    CONTENTS.  XVU 

PAGE 

Family  II.— Ukocebidae  (\V^ood-wasps). 

1.  Sirex  juvencux  (Steel-blue  wood- wasp) 355 

2.  S.  glfjax  (Yellow  wood-wasp)  ...  .     357 

Family  III.— Cyxii'idae  (Gall-wasps) 358 

(Z?.)  Diptera. 

Family  I. — Gkcidomyiidae  (Gall-gnats). 

1.    Cri'Hhiinijla  mViciperda  (WiWow  <j:,-A\\-gni\V) 360 

{('.)  Hemiptera. 

Family  I. — Aphididae  (Plant-lice). 

1.  f/wnwes- rt7(/c/;.'(  (Spmce-gall  Aphis) 361 

2.  C.  cocclneux 364 

3.  C.  .ifi-ohilobiux  (Larch  Aphis) 36-t 

4.  C.  sihiricu.'i 365 

Family  II. — Coccidae  (Scale-insects). 

1.  Coccus  fugl 366 

1,   Lecanium  hemicrijphum 367 

(Z*.)  Orthoptera. 
Family  I.— Gryllidae  (Crickets). 

1.   Grijllotalim  vulgaris  (Mole-criciiet) 368 

Family  II.— Aceidiidae  (Locusts). 

1.   Pachi/fgh/n  migratoriiis  {Migratorj  locust) 372 

List  of  Trees  with  the  Insects  which  attack  them      .  373 


PAKT   III. 
PROTECTION  AGAINST  PLANTS. 

CHAPTER   I. 
PROTECTION   AGAINST   FOREST   WEEDS.     . 

Section  I. — General  Account. 

1 .  Definition ....  386 

2.  Classification 386 

3.  Utility  of  certain  weeds 390 

4.  Damage  done  by  forest  weeds         ....  .         .  390 

5.  Preventive  measures 395 

G.  Remedial  measures 397 

F.p.  h 


XVlll  TABLK    OF   CONTENTS. 

Section  II. — Special  Account.  pa(;e 

1.  Lightdemanding  weeds 31)9 

2.  Half-shadebearers 403 

3.  Shadebearing  weeds 408 

4.  Weeds  of  wet  peaty  soil 401) 

5.  Lianes 410 

6.  Parasitic  phanerogams 412 

7.  Weeds  actiug  as  hosts  to  injuiious  fungi 418 

8.  Classification  of  weeds  in  order  of  iujuriousaess          .         ...  420 


CHAPTER  ir. 
rROTECTION   AGAINST    FUNGI. 

Section  I.— General  Account. 

1.  Position  of  fungi  in  vegetable  kingdom 421% 

2.  Classification  and  importaqce 422 

3.  Mode  of  life 423 

4.  Distribution 427 

Section  II. — Fungi  attacking  Conifkus. 

1.  Ariibillarea  III  ell ea  (Jioney  hingiis) 429 

2.  Fames  anno^us 435 

3.  Rhiziua  inflata 437 

4.  Trametes  Pini 438 

5.  Peridermuuii  P'nii  (cortlcuhi^  (Pine-blister) 441 

6.  P.  Strobi 443 

7.  Melampsom  Piniforqiia  (Pine  branch-twist)  ....  444 

8.  Melaiiijjsurella  C'ai-yoj^Jii/llacearum  (Silver-fir  canker)         .         .     .  448 

9.  Xectria  Cucurlntida 452 

10.  DaHyxcyplM  calycina  (Larch-blister) .......  454 

11.  Cfe«a«;7mw -4&(>^M- (Pine-shoot  fungus). 459 

12.  Peatalozzla  Hartig'd 460 

13.  Septoria  2)arasitiva 460 

14.  Botritis  Douglami 461 

15.  Perldermium  Pini  {acicola)     ........  461 

16.  Aecidium  abietiuuiit   ..........  462 

17.  A.  colli lunare 462 

18.  Chryin»nij,ra  Ahtctis   ..........  463 

19.  Lujihoderinium  I'iiuixtri  (Pine  ueedle-cast)    ......  465 

20.  L.  macrusj/orium 467 

21.  L.  nercisequium 468 

22.  Spliaerella  laricina 469 

23.  Trichosphaeria imrasiiica        ........  470 

24.  Ilerjiotrichia  nigra      ..........  172 

25.  Aecidium  strohilinuin      .         .         .         .         .         .         .         .         .472 


TABLE    OF   CONTENTS.  XIX 

PAGE 

Section  III. — Fungi  attackino  Broad-leaved  Treks. 

1.  ItoselUma  quercitui 473 

2.  Pulijporus  sulj>hurem 47."> 

8.  Xectria  ditmima  (Beech-cankov) 477 

4 .  y,  c'uiimharlna  (Coral-spot  disease) 471) 

f).   Aijlaospora  taleolu     ..........  481 

<!.  Pliytuphthom  Fagi  (Beach  sccdliug  mildew) 482 

7.  lihijtisma  acerinuiii,    .         .         .         .         ^ 483 

8.  Melampaora  Hartlgii 485 


PART   IV. 

PROTECTION  AOAINST  x\.Tx\IOSPaERIC  INFLUENCES. 


CHAPTER    I. 

I'KOTECTION   AGAINST   FUOST.      . 
Section  I.— Frozen  Plant-Organs. 

1.  Exterual  appearance 492 

2.  Explanation  of  the  action  of  frost  on  plants 492 

3.  Damage  done  ...........  494 

4.  Register  of  severe  frosts      .        • 502 

5.  Protective  measures 502 

Section  II.— Frostcrack  505 

,,         1II.--FROST-CANKER 510 

„       IV.— Uprooting  of  Seedlings  by  Frost 510 

CHAPTER   II. 

PKOTECTION   AGAINST   INSOLATION. 
Section  I.— Drought, 

1.  Appearance  and  cause  of  injury 514 

2.  Damage  done 514 

3.  Ivegistcr  of  dry  yeai-s 518 

4.  Protective  rules .         ..........  519 

Section  II. — Bark-Scokching 522 

III.— Heat-cback 520 


XX  TABLE    OF   CONTExNTS. 

CHAPTER   III. 
I'KOTECTION   AGAINST    WIND. 

PAGE 
SKCTIOK  I.— rifKVALKNT  WlNDS. 

1.   Damage  done  .........     5-7 

'2.   I'roteclivc  rules  ...........     i"J29 

SECTiOiS  II.— Storms. 

1.  Origin o31 

2.  Damage  done 533 

3.  Register  of  storms 540 

4.  Protecttre  rules     ...........  542 

5.  Treatment  of  windfalls 550 

G.  Treatment  of  injured  woods 551 

CHAPTER   IV. 
PIIOTECTION   AGAINST   VIOLENT   KAIN. 

1.  Damage  done 554 

2.  Protective  rules 555 

CHAPTER   V. 
PROTECTION   AGAINST   HAIL. 

1 .  Damage  done 557 

2.  Prevalence  of  hail-storms 558 

3.  Protective  measures 560 

CHAPTER  VI. 
PIIOTECTION   AGAINST  SNOW. 

1.  Damage  done • 561 

2.  Record  of  bad  years 561) 

3.  Protective  rules     .         .         .         ; 570 

4.  Treatment  of  injured  woods 572 

CHAPTER   VII. 
PROTECTION   AGAINST   RIME. 

1.  Damage  done 574 

2.  Record  of  bad  years 576 

3.  Prutcctive  rules 578 

4.  Treatment  of  injured  woods 578 


TABLE    OF    C0NTP:NTS. 


PAET   V. 


PEOTECTION  AGAINST  NON-ATMOSPHEEIC  NATURAL 
PHENOMENA. 


CHAPTER   I. 

PROTECTION   AGAINST   DAMAGE    BY   WAfEK. 

PAGE 

Section  1.— Soil-Denudation 582 

„       II. — Inundations 586 

.,     III.— Swamps. 

1 .  Formation 596 

2.  Damage  done .  597 

3.  Pi-otective  rules 601 

Section  IV. — Drainage. 

1 .  Vertical  drainage  .        .        .      • 604 

2.  Surface  drainage 604 

3.  Covered  drains 612 

CHAPTER    n. 
PROTECTION   AGAINST   AVALANCHES         .        .        .        .616 


CHAPTER    III. 

PROTECTION   AGAINST   SHIFTING   SAND. 
Section  I. — Sand  Dunes. 

L  Description 621 

2.  Construction  of  littoral  dune 023 

3.  Material  for  fixing  the  sand  .         .         . 624 

4.  Maintenance  of  the  littoral  dune 625 

5.  Protective  coast  forest  zone 626 

Section  II. — Inlant)  San'd. 

1.  Description 630 

2.  Protective  rules ....  630 

3.  Fixation  of  the  sand 631 

4.  Stocking  the  area 634 


XXI I 


TABLE    OF   CONTENTS. 


CHAPTER   IV. 

PROTECTION   AGAINST   FOKEST    FIRES. 
Section  I. — Foeest  I^'ires  caused  by  Hu.max  Agexcy.  page 

1.  Causes 638 

2.  Kinds  of  forest  fires Gii'J 

3.  Damage  done 640 

4.  Register  of  fires i>V> 

").  Protective  measures (JI7 

6.  Rules  for  extinguishing  forest  fires 654 

7.  Watching  site  of  fire 656 

8.  Treatment  of  injured  woods 657 

9.  Insurance  against  forest  fires 657 

Section  II. — Effects  of  Lightning  on  Tuees 658 


PART   VI. 
PROTECTION  AGAINST  CERTAIN  DISEASES. 


CHAPTER    L 
GENERAL  ACCOUNT 671 

CHAPTER   II. 
RED   ROT, 

1.  Description 673 

2.  Modifying  factors 674 

3.  Causes 675 

4.  Damage  done 677 

5.  Treatment 677 

CHAPTER   III. 
WHITE   ROT       .        .      ' 679 

CHAPTER    IV. 

STAG-HEADEDNESS. 

1.  Description  and  causes  .........     680 

2.  Treatment 683 


TABLE    OF   CONTENTS. 


:xxiii 


CHAPTER   V. 

ABNORMAL   NEEDLE-CAST. 

PAGE 

L  Description    ............  680 

2.  Modifyiiif^  factors       ..........  6S() 

3.  Geographical  range GS7 

i.  Causes 088 

o.  Damage  done         ...........  090 

0.  Treatment 01)0 


CHAPTER  VI. 

DAMAGE    BY   ACID   FUMES   FKOM    FURNACES,   kc. 

1.  Description  of  injury         .........  (J'J.") 

2.  Injurious  components  of  smoke 096 

3.  Damage  done 699 

4.  Methods  of  recognizing  damage  .......  705 

5.  Protective  measures  ..".......  707 

6.  Estimation  of  damage 707 


FOREST    PROTECTION 


INTRODUCTION. 

1.  Definition  of  the  Term  Forest  Protection. 

Forests  may  be  protected  by  two  agencies : — 

By  the  State,  through  laws  and  regulations  made  for  the 
general  welfare  of  the  country  and  forming  the  subject  of 
Forest  Lair. 

By  the  Oicner  of  the  forest,  in  his  private  capacity ;  only 
this  part  of  the  subject  comes  under  the  term  Forest  Proteetion, 
which  may  therefore  be  defined  as  follows  : — 

Forest  Protection  has  for  its  object,  the  securittj  of  forests, 
as  far  as  lies  within  the  poicer  of  their  ouners,  against  unfavour- 
able external  influences. 

The  measures  to  be  taken  in  order  to  protect  a  forest 
may  be  : — 

Preventive  or  remedial,  according  as  their  object  is  to  ward 
off  certain  dangers,  or  to  remedy  evils  which  the  forest  has 
already  incurred. 

The  essential  conditions  of  successful  Forest  Protection 
are : — 

Knowledge  of  the  phenomena  and  causes  of  all  damage 
which  may  threaten  forests. 

Knowledge  of  the  available  preventive  and  remedial 
measures. 

A  proper  application  of  the  above  knowledge  to  any  special 
case  of  damage  which  may  arise. 

•2.  Position  of  Forest  Protection  in  Forestry. 

The  position  of  Forest  Protectiofi  in  the  science  of  forestry 
will  be  seen  from  the  following  considerations : — 

Sylviculture  teaches  us  how  to  form,  tend,  and  regenerate 

F.P.  B 

Library 
N.  C,  State  CoUefir*^ 


2  INTRODUCTION. 

forests;  Forest  Protection, hov{  to  guard  them  against  injurious 
external  influences,  and  is  followed  by  Forest  Utilisation,  which 
shows  how  to  utilise  a  forest  in  the  most  suitable  manner. 
These  three  branches  of  Forestry  are  also  included  in  the 
term  Forest  Production,  while  the  remaining  branches  are 
comprised  under  Forest  Management,  which  includes  Mensura- 
tion and  Valuation  of  Forests,  Workimj- Plans,  and  Political 
Economy  applied  to  forests,  which  may  be  termed  Forest 
Policy. 

3.  Historical  Notice. 

The  first  trace  in  history  of  forest  protection  consists  in  that 
afforded  to  sacred  groves  and  trees.  We  read  of  such  groves 
in  the  Bible  and  in  Tacitus,  and  they  still  exist  in  India, 
especially  in  the  hill-tracts  south  of  Assam.  In  Europe,  the 
oak  and  lime  appear  to  have  been  the  trees  looked  upon  as 
most  sacred,  and  in  the  Himalayas,  the  deodar  (God's  tree). 

The  Ban  forests  of  the  middle  ages,  established  by  the 
Emperors  of  Germany  and  other  royal  or  noble  personages 
who  wished  to  secure  sufficient  tracts  of  forest  for  the  pre- 
servation of  deer  and  other  game,  formed  the  next  stage. 
The  Windsor,  Epping,  and  Dean  forests,  the  New  Forest,  and 
some  other  smaller  forest  areas  are  the  relics  of  former 
extensive  tracts  reserved  as  hunting-grounds  by  the  Norman 
kings  of  England. 

The  forest  laws  of  the  middle  ages,  besides  being  chiefly 
concerned  in  the  preservation  of  game,  contain  many  provisions 
regarding  boundaries,  forest  fires,  mast,  forest  pasture,  damage 
to  trees,  etc.  In  the  Salzburg  Forest  Ordinance*  of  1524,  for 
instance,  directions  are  given  regarding  boundary  marks.  In 
a  Bavarian  forest  ordinance  of  1568,  the  influence  of  the  west 
wind  on  the  natural  regeneration  of  forests  is  referred  to,  and 
directions  are  given  to  leave  a  protective  belt  of  trees  to  the 
west  of  a  felling-area. 

In  1665,  the  famous  Ordonnance  dcs  fori'ts  proposed  by 
Colbert  was  sanctioned  by  Louis  XIV,  and,  amongst  other 
improvements,  put  an  end  to  the  grazing  of  sheep  and  goats 
in  the  French  Crown  forests. 

*  H.  Eding,  "  Die  Rcchtsverhaltnisse  des  Waldes."     Berlin,  1874,  p.  36. 


INTRODUCTION.  8 

Hans  von  Carlowitz  in  1713,  in  his  classical  work  Si/IricuJtura 
(Economica,  which  is  chiefly  devoted  to  sylviculture,  describes 
several  measures  of  forest  protection,  including  a  regulation 
made  in  1680  against  caterpillars. 

As  regards  damage  by  game,  Burgsdorf  wrote  in  1796  con- 
cerning the  peeling  of  bark  by  deer.  At  the  commencement 
of  the  nineteenth  century,  the  damage  done  to  forests  by  game 
was  very  considerable  ;  in  a  battue  held  by  King  Frederick 
of  Wiirtemberg  in  1812  in  the  beech  forests  near  Tiibingen, 
823  deer  and  wild  pigs  were  killed  in  two  hours.  Only 
since  the  eventful  year  1848  has  damage  by  game  to  forests  in 
Germany  considerably  diminished,  and  become  more  localised 
by  the  constitution  of  special  parks  for  game.  Such  was  the 
forest  of  Compiegne  under  Napoleon  III.,  where  all  the  forest 
revenues  were  absorbed  by  the  cost  of  fencing  and  planting  the 
young  woods,  and  where,  in  1870,  several  hundred  red-deer 
and  thousands  of  roes,  besides  much  smaller  game,  were  killed. 

In  England,  James  the  First  was  the  first  monarch  who 
considered  forest  trees  of  more  importance  than  game ;  he 
obtained  much  unpopularity  by  enclosing  part  of  Windsor 
Forest,  and  put  an  end  to  the  pollarding  of  maiden  oak-trees, 
which  were  lopped  in  winter  to  enable  the  deer  to  browse  off 
the  bark  of  the  lopped  branches.  None  but  pollard  oak  have 
been  lopped  in  this  way  since  1608,  and  the  hollow  old  oak 
pollards  now  in  the  Windsor  Forest  were  in  existence  before 
that  date.  That  king's  fondness*  for  knocking  rabbits  on 
the  head  with  a  stick  would,  however,  be  amply  satisfied 
were  he  now  at  Windsor,  as  rabbits  have  increased  in  the 
most  alarming  manner  during  the  last  20  years,  and  have 
destroyed  the  valuable  undergrowth  over  large  areas  of  the 
forest.  They  render  the  reproduction  of  the  trees  exceedingly 
difficult  and  expensive,  and  altogether  nullify  the  proper 
management  of  the  large  area  of  oak  forest  planted  for  the 
nation  in  1816-25.  Such  wholesale  destruction  of  valuable 
woods  by  rabbits  would  not  be  allowed  in  any  other  European 
Crown  forest. 

Forest  grazing  was  regulated  in  1585  by  the  ordinance  of 
Mansfeld,    which   prescribed   a  5-years   close  season  for  all 

♦  Hepworth  Dixon,  "  Royal  Windsor." 

B    2 


4  INTRODUCTION. 

coppice  woods  with  12-yeai's  rotation.  Forest  pasture,  and 
pannage,  or  the  eating  of  mast  by  pigs,  have  greatly  fallen 
off  in  importance  of  late  years,  but  in  earlier  times  these 
foi-est  usages  vied  in  importance  with  that  of  hunting. 

The  great  damage  done  to  forests  by  insects  was  first  noted 
in  Germany  in  1780,  and  between  that  date  and  1830  several 
works  on  Forest  Entomology  appeared.  That  by  Eatzeburg 
was  published  in  1837,  and  another  by  Altum  in  1872. 
Ratzeburg's  book  was  revised  and  enlarged  by  Judeich  and 
Nitche  in  1885  and  in  1895. 

The  engineer  Bremontier  undertook  the  fixing  of  the  shifting 
sands  on  the  west  coast  of  France  in  1800,  on  lines  already 
proposed  by  Baron  de  Charlevoix  Villers  in  1786.  A  French 
law  on  that  subject  was  passed  in  1810.  Oberforster  von  Kropf 
did  a  similar  service  for  Germany  at  about  the  same  time. 

The  great  damage  done  in  1856,  by  floods  in  the  Rhone 
Valley,  induced  the  French  to  pass  in  1860  a  law  for 
'*  rehoiscment  des  montagnes.'" 

Forest  fires  were  formerly  of  frequent  occurrence  in  France 
and  Germany,  but  are  now  regarded  af^  national  calamities, 
and  rarely  allowed  to  extend  over  considerable  areas.  A  special 
law  against  forest  fires  in  Dauphiny  was  passed  in  1872,  and 
revised  in  1893.  They  are  still  prevalent  on  a  large  scale  in 
Russia  and  Greece,  and  in  North  America.  In  British  India, 
for  the  last  30  years,  a  steadily  increasing  success  has  been 
attained  by  the  Government  in  its  efforts  to  reduce  the  area 
of  State  forests  burned  annually,  and  measures  for  protecting 
36,651  square  miles  of  State  forest  from  fire  were  taken  in  1903. 

The  preservation  of  birds  useful  in  forestry  and  agriculture 
has  been  furthered  by  the  naturalists  of  different  European 
countries  and  by  the  enactnient  of  special  laws.  At  the  same 
time,  the  British  gamekeeper  by  indiscriminately  destroying 
birds-of-prey  and  the  smaller  carnivora,  has  allowed  rabbits 
and  wood-pigeons  to  increase  so  enormously,  as  to  become  a 
veritable  scourge  to  forestry  and  agriculture,  to  say  nothing  of 
even  greater  danger  from  mice  and  voles. 

Lastly,  the  researches  of  Willkomm  in  1866,  and  of  Robert 
Hartig  in  1874,  have  brought  to  light  the  causes  of  many 
diseases  of  forest  trees  which  are  due  to  fungi. 


INTRODUCTION.  5 

4.  Arrangement  of  Material. 

The  measures  to  be  taken  by  the  owner  for  the  protection 
of  his  forests  may  be  arranged  under  the  following  heads  : — 

Protection  of  forests  against  man,  animals,  plants,  atmo- 
spheric influences  (frost,  heat,  wind,  rain,  hail,  snow  and 
rime)  ;  against  extraordinary  natural  phenomena  (inundations, 
avalanches,  shifting  sand  and  forest  fires) ;  and  against  certain 
diseases  the  causes  of  which  are  doubtful,  stagheadedness,  and 
factory  fumes. 

A  detailed  list  of  the  headings  are  given  at  the  commence- 
ment of  this  book. 

It  will  be  noticed  that  some  of  the  protective  measures  sug- 
gested in  certain  cases  are  conflicting  ;  thus  woods  should  be 
cut  from  west  to  east,  in  order  to  protect  them  against  cutting 
east  winds,  but  from  east  to  west,  when  liable  to  be  thrown 
by  strong  westerly  gales.  Stumps  must  be  extracted  to  pre- 
vent the  breeding  of  certain  insects,  but  should  be  left  on 
hill-sides,  when  there  is  danger  of  erosion.  The  forester  will, 
however,  have  little  difficulty  in  deciding,  for  any  case,  which 
is  the  greater  danger,  and  will  bear  that  chiefly  in  mind  in 
protecting  his  woods. 

5.  List  of  Sciences  on  which  Forest  Protection  is  based. 

Jurisprudence,  chiefly  as  regards  landed  property  and 
servitudes. 

Zoology,  chiefly  of  game  and  forest  insects. 

Botany  and  Mycology. 

Physiography  and  Meteorology. 

Other  branches  of  Forestry  (Sylviculture,  Forest  Utihsation, 
and  Forest  Pohcy). 

A  knowledge  of  forest  legislation  and  of  game  laws  is  also 
useful. 


PART  I. 

PROTECTION   OF  FORESTS   AGAINST   MAN. 


PROTECTION   OF   FORESTS  AGAINST  MAN. 

The  damage  which  may  he  caused  to  forests  hy  our  fellow- 
creatures  may  he  classified  as  follows  : — 

Injuries  to  forest  houndaries. 

Irregularities  in  utilising  forest  produce. 

Theft  of  forest  produce  and  damage  to  forests,  or  forest 
offences. 

Excesses  by  holders  of  forest  servitudes. 

It  is  the  duty  of  the  forester  to  maintain  the  boundaries  of 
the  forest  entrusted  to  his  care,  to  counteract  irregularities  in 
utilising  it,  to  prevent  theft  of  forest  produce  and  damage 
to  the  forest,  and  also  excesses  in  the  exercise  of  forest 
servitudes. 


10 


CHAPTEK  I. 

PROTECTION    OF    FOREST    BOUNDARIES.* 

A  CLEARLY  defined  and  permanent  demarcation  of  a  forest 
stands  in  the  first  rank  of  the  protective  measures  for  forest 
property.  It  protects  the  forest  against  fraud  and  damage, 
and  aflbrds  security  for  all  the  details  of  forest  management. 

The  different  points  which  require  consideration  under  this 
heading  are : — 

The  various  kinds  of  forest  boundaries. 

Settlement  of  do. 

Demarcation  of  do. 

Survey  of  do. 

Description  of  do. 

Legalisation  of  do. 

Upkeep  of  do. 

Cost  of  do. 

Improvement  of  do. 

1.   The   Various  Kinds  of  Forest  Boundaries. 

Boundaries  are  of  two  principal  kinds,  property  and  ad- 
ministrative boundaries. 

By  the  term  property  boundaries  is  meant  those  that  separate 
estates,  or  portions  of  the  same  estate  subject  to  servitudes. 

Property  boundaries  may  be  either  external  or  internal 
surrounding  enclosures.  Boundaries  of  servitudes  separate 
those  parts  of  an  estate  that  are  affected  l)y  rights  of  third 
parties  from  those  which  are  not  so  affected.  Parts  of  a  forest 
may  be  leased  for  sporting  or  other  purposes,  and  their 
boundaries  must  be  clearly  defined. 

Administrative  boundaries  may  indicate  :■ — 

Administrative  units,  such  as  beats,  ranges,  divisions,  etc.,  or, 

Working  units,  as  compartments,  periodic  blocks,  working- 
sections,  working-circles,  etc. 

*  Eding,  H.,  "  Die  Rechtsveihaltnisse  des  Waldes."  Berlin.  1874.  Kalk,  U., 
"  Die  Sicherung  der  Forstgrenzen."     Eberswalde,  187'J. 


FOREST    BOUNDARIES. 


11 


2.  Settlement  of  Boundaries. 

All  forests  must  be  properly  demarcated  by  bomidaries. 

The  procedure  for  settling  boundaries  differs  according  as 
they  are  2^>''>P^'f'fiJ  or  administratire  boundaries.  Administra- 
tive boundaries  depend  merely  on  the  will  and  pleasure  of  the 
owner  of  the  estate,  and  the  details  regarding  them  are  dealt 
with  under  Working -Plans. 

Property  boundaries  must  be  accurately  defined.  This  is 
of  the  greatest  importance  to  the  owner  and  also  to  the  'public, 
so  as  to  prevent  uncertainty  and  unnecessary  work  for  the 
executive  and  legal  machinery  of  the   State.     Hence  in  all 


Fi-.  1. 


Fig.  2. 


civilised  countries  the  procedure  for  settling  property  bound- 
aries is  laid  down  by  law.  Evidence  as  to  the  correct 
boundary  consists  in  existing  boundary  pillars  or  traces  of 
where  they  have  been,  statements  of  old  people  who  know  the 
l)oundaries,  and  boundary  maps.  The  settlement  is  best  done 
by  a  public  surveyor,  who  may  be  either  chosen  by  the  parties 
concerned,  the  adjacent  owners,  or  by  the  executive  State  or 
local  authority. 

During  the  boundary  settlement  the  adjacent  proprietors 
should  be  present  personally,  or  by  their  legally  appointed 
agents,  and  boundaries  which  may  be  regulated  in  their 
absence  after  a  formal  summons  to  be  present  will  be  held  to 
have  been  duly  accepted  by  them.  The  surveyor  should 
endeavour  to  lay  down  the  boundary  on  the  ground  by  friendly 
agreement  between  the  parties ;  if  he  should  not  succeed,  the 
competent  law-courts  or  officials  must  decide  disputed  points. 

The   surveyor  should  fix  the  boundary  lines  as  long  and 


12 


PROTECTION    AGAINST    MAN. 


straight  as  possible,  in  order  to  render  the  estates  more 
valuable,  and  to  keep  down  the  cost  of  demarcating  and 
maintaining  the  boundary.  This  maxim  should  not,  however, 
be  carried  too  far,  when  by  so  doing,  boundary  points  would 
be  situated  in  impassable  places,  such  as  swamps,  etc. 

All  boundary  points  which  have  been  finally  settled  should 
at  once  be  marked  by  durable  posts,  and  by  digging  narrow 
trenches  in  the  direction  of  the  boundary  lines  (Fig.  1),  or  in 
a  circle  round  each  post  (Fig.  2).  During  the  progress  of  the 
boundary  settlement,  the  surveyor  should  make  a  rough  plan 
of  the  boundary  line,  and  keep  notes  of  the  evidence  brought 
before  him. 


Fig.  3. — Partition  of  an  island  by  the  line  MM,  mid-stream,  between  two  adjacent 
owners,  A.  and  B.,  into  two  parts  A,  B^. 


Fig.  4. — Partition  of  a  river-side  accretion  C,  by  the  line  a  b  e. 


3.  Demarcation  of  Boundaries. 

The  demarcation  of  boundaries  is  effected  by  natural,  arti- 
ficial, or  mixed  boundaries. 

Property  boundaries  require  to  be  more  permanently  marked 
than  administrative  boundaries. 


FOREST    BOUNDARIES.  1-3 

a.  Natural  Boundaries. 

Natural  boundaries  are  : — 

Water-partings, 

Water-courses, 

Marked  trees,  etc. 
With  the  exception  of  water-partings  no  natural  boundaries 
are  very  permanent.  Streams  frequently  alter  their  course, 
and  trees  are  liable  to  die  or  be  blown  over  or  'cut  down.*  At 
the  same  time,  wherever  the  course  of  a  stream  is  fairly  well 
fixed,  as  in  a  deep  valley,  such  a  natural  feature  forms  a  good 
and  economical  boundary  between  two  properties.  In  the 
case  of  water-courses,  mid-stream  is  generally  considered  the 
boundary  as  in  Fig.  5.  Where  deposits  of  new  land  occur, 
they  belong  as  a  rule  to  the  proprietor  who  owns  the  shore 
along  which  they  occur.     If  several  owners  participate  in  the 


Fig.  5. — "Water- course  with  boundary  marks. 

shore,  the  new  boundaries  are  indicated  by  producing  the 
original  boundary  line  through  the  new  accretion  to  the  water- 
side as  shown  in  Fig.  4.  In  the  case  of  erosion  and  re-deposit, 
laws  differ  ;  in  some  cases,  the  owners  can  claim  the  area  thus 
lost  and  re-deposited.  In  other  cases,  as  in  certain  parts  of 
British  India,  new  islands  formed  in  the  middle  of  a  river 
belong  to  the  State.  Owners  are  allowed  to  prevent  erosion 
by  artificial  works,  fixing  the  banks,  etc.  It  is  not,  however, 
permissible  to  induce  deposits  by  artificial  means.' 

For  greater  security  natural  boundary  lines  may  be  marked 
by  numbered  marks  similar  to  those  described  below  for  arti- 
ficial boundaries.     If  the  centre  of  a  stream  is  the  boundary, 

*  Pollarded  trees  often  serve  as  boundary  marks  in  private  forests  near  the 
river  Rhine.  They  are  thus  easily  distinguished  from  the  other  trees,  that  are 
not  pollarded.  Slips  of  poplars  or  willows  may  be  planted  on  favourable  soil  to 
serve  as  boundary  marks.  These  may  be  subsequently  pollarded.  In  India, 
species  of  Ficus  may  be  used. 


14 


PROTECTION    AOAINST    MAN. 


the  l)oimdary  marks  are  placed  alternately  on  either  side  of 
it,  as  in  Fig.  5,  hut  only  on  one  side  of  it  if  the  hank  he  the 
houndary. 

h.  Arlifirial  Boundaries. 

Artificial  houndary  lines  consist  of  : — 
Eoads,  or  lines  of  houndary  marks. 
The  line  of  a  road  may  have  to  he  changed,  especially  at 
certain  points  to  reduce  too  steep  a  gradient,  and  this  may  he 
an  objection  in  some  cases  to  a  road  as  a  permanent  houndary, 
hut  a  well  aligned  road  forms  an  excellent  and  economical 
forest  houndary,  and  facilitates  the  export  of  produce  from 
the  forests  on  either  side  of  it. 

Lines  of  houndary  marks  may  he  demarcated  by  mounds  of 
earth  or  stones  ;  hy  wooden  or  iron  posts,  masonry  pillars,  or 
cut  stone  blocks.  All  boundary 
marks  should  he  numbered  con- 
secutively, and  the  numbers  on 
them  painted  black  or  white  accord- 
ing to  the  colour  of  the  marks. 
The  marks  for  each  separate  forest 
property  are  usually  numbered  from 
iiorth  to  west  and  hy  south  to  east, 
and  on  propert}'  houndary  marks 
the  initial  letter  of  the  owner's 
name  may  he  added.  Every  enclo- 
sure in  a  forest  belonging  to  another 
owner  than  that  of  the  forest  should 
be  surrounded  by  similarly  num- 
bered boundary  marks. 

In   case   of    any   addition   to   a 

forest    involving    fresh    houndary 

marks  being  interposed  between  two  formerly  existing  marks, 

letters  a,  b,  etc.,  may  be  added  to  the  earlier  number  to  denote 

their  position. 

Fig.   6  shows  the  usual  mode   of   representing   a   line   of 
boundary  marks,  on  a  map. 

The  nature  of  the  boundary  will  differ  according  as  the  ad- 
joining estate  is  woodland,  or  cleared  for  agriculture.     In  the 


bdtmdarv  lino. 


FOREST    BOUNDARIES. 


■  R.v.P 
••  No 


3 


former  case,  a  strip  of  a  certain  breadth  inside  the  boundary 
may  have  to  be  kept  clear  of  forest  growth.  The  choice  of 
the  kind  of  boundary  mark  depends  on  circumstances,  but 
stone  or  masonry  pillars  are  generally  to  be  preferred.  In 
cases  where  a  rapid  demarcation  is  necessary,  and  cut  stones 
or  even  bricks  are  not  easily  procurable,  as  in  certain  districts 
in  India,  conical  mounds  of  earth  or  of  stones,   with  posts 

in   the  centre,    are  sometimes  used,,  at  any 

rate    until  more  permanent    marks   can   be 

supplied. 

In  constructing  such  mounds,  the  post,  made 

of  heartwood  only  and  of  the  most  durable 

timber  available,  is  first  planted  in  the  soil, 

the  portion  in  the  ground  having  been  charred, 

or  the  whole  post  creosoted  or  tarred  so  as  to 

ensure  greater  durability.     Eound  the  post 

two  circles  are  then  traced  in  the  ground,  and 

earth       to       be 

heaped  up  must 

be      dug      from 

beyond  the  outer 

circle  and  placed 

within  the  inner 

one.      Otherwise 

the   heap   would 

soon  settle  down 

into   the  trench. 

The  mounds  may 

be  made  of  stones 
if  available.  The  slope  of  the  mounds  will  correspond  with 
the  natural  angle  of  repose  for  the  class  of  material  employed, 
and  their  height  should  be  about  four  feet.  Earthen  mounds 
should  be  carefully  protected  by  placing  sods  on  their  surface. 
Wooden  posts  without  mounds  may  also  be  used  as  boundary 
marks,  but  they  are  then  more  liable  to  be  thrown  down  by 
cattle,  or  wild  animals,  or  to  be  removed.  In  either  case 
the  posts  should  bear  current  numbers,  a  very  durable  form 
being  a  cast-iron  plate,  in  which  the  number  is  embossed 
or  the  numbers  may  be  painted  on  the  posts. 


Fig.  8. — Boundary  stone. 


16  PROTECTION    AGAINST    MAN. 

Hess  gives  a  useful  kind  of  iron  boundcary  mark  as  shown 
in  Fig.  7.  The  lower  and  upper  plates  can  be  removed  to 
facilitate  transport.  Stones  are  heaped  on  the  lower  plate 
after  it  has  been  put  into  the  ground  to  the  required 
depth. 

The  best  of  u\\  boundary  marks  are  generally  hewn  stones 
(Fig.  8),  or  masonry  pillars.  The  former  may  be  prismatic, 
triangular,  or  rectangular  in  se'ction,  with  a  rounded  top  on 
which  lines  are  cut  showing  the  directions  of  the  two  adjacent 
pillars.  Serial  numbers  should  be  cut  on  one  of  the  faces  of 
pillar.  The  lower  portion  to  be  placed  in  the  ground  should 
be  left  rough  and  be  of  larger  bulk  than  the  cut  portion,  so  as 
to  ensure  stability. 

Care  should  be  taken  to  select  durable  material  such  as 
granite,  basalt  or  quartzite  for  these  stones. 

Where  hewn  stones  are  not  available,  pillars  of  brick  and 
mortar  or  rubble  masonry  may  be  erected,  a  sufficient  founda- 
tion being  of  course  provided.  The  current  number  is  carved 
on  a  small  flat  piece  of  stone  or  slate  inserted  in  the  sloping 
top  of  the  pillar.  This  is  greatly  preferable  to  inserting  the 
number  on  a  prismatic  piece  of  stone  let  into  the  apex  of  the 
pillar,  as  is  sometimes  done.  Such  pieces  are  easily  loosened 
by  boys  engaged  in  tending  cattle  or  sheep  near  the  forest 
boundary.  These  pillars  should  be  formed  of  cubes  with 
a  side  of  2^  to  3  feet,  surmounted  by  a  pyramid  6  to  9  inches 
high. 

It  is  customary  in  India  to  bury  a  quantity  of  charcoal  under 
boundary  pillars,  so  as  to  assist  detection  of  any  fraudulent 
change  in  their  position. 

In  all  lines  of  boundary  marks,  one  mark  should  be  placed  at 
each  angle,  and  whenever  two  angular  points  of  the  boundary 
are  too  distant  to  be  seen  from  one  another,  a  sufficient  number 
of  intermediate  pillars  should  be  erected.  The  intermediate 
pillars  need  not  be  so  substantial  as  the  corner  pillars. 

If  the  boundary  is  merely  a  line,  the  pillars  are  placed  along 
its  centre,  but  if  pillars  are  placed  along  a  road,  tlie  middle  of 
which  forms  the  boundary,  they  should  be  alternately  on  either 
side  of  it. 

After  boundary  lines  have  been  laid  out,  their  exact  position 


FOREST    BOUNDARIES. 


ir 


may  be  more  cleavl}^  defined  by  rows  of  trees,  hedges,  fences, 
walls,  forest  rides,  or  ditches. 

lioics  of  trees  are  injurious  to  neighbouring  fields  by  their 
shade  and  the  spread  of  their  roots.  Hedges  are  difficult  to 
keep  in  order,  and  rarely  answer  their  purpose  in  keeping  out 
cattle  along  a  lengthy  forest  houndary.  Fences  are  expensive, 
but  their  use  is  sometimes  unavoidable  where  browsing  by 
game  or  grazing  is  to  be  feared.  Details  regarding  fences  are 
given  in  Schlich's  Sylviculture,  Vol.  II.,  3rd  edition,  page  122. 

Walls  may  be  erected  when  stones  can  be  collected  on  the 
spot,  or  where,  on  account  of  the  sloping  nature  of  the  ground. 


□T 


II 


a 


Fig.  9. 


Fig.  10. — Boundary-ditches. 


I 

ii  I 

Fig.  11.     Fig.  12. 


ditches  are  not  practicable.  Such  walls  should  be  1  yard  broad 
at  the  base  and  from  a  height  of  18  inches  should  gradually 
taper  off  to  the  top.  The  stones  should  be  placed  with  the 
thick  end  outside. 

Forest  boundary  rides  as  well  as  boundary  marks  are  neces- 
sary where  two  forests  adjoin.  Unless  the  ride  is  also  to  be 
used  as  a  road,  a  breadth  of  4  to  8  feet  will  suftice,  16  feet  being 
the  least  admissible  breadth  for  a  road,  so  that  two  carts  may 
pass  one  another.  Along  boundary  rides  it  may  be  advisable  to 
dig  out  all  stumps  in  order  to  prevent  the  growth  of  coppice- 
shoots,  and  the  ground  may  be  roughly  levelled  and  drained, 
and  even  narrow  bridges  erected,  so  as  to  convert  the  ride  into 
a  bridle-path  to  facilitate  inspection. 

Boundary  ditches  (Figs.  9  to  12)  give  a  clearly  cut  line  and 
prevent  encroachment  by  ploughing  or  grazing  when  the  forest 

F.P.  c 


18 


PROTECTION    AOAINST    :\1AN. 


Ijoiindary  runs  along  a  field  or  meadow.  Such  ditches  can 
usually  be  dug  except  on  very  stony  or  steep  ground  ;'  they  run 
either  along  the  entire  boundary  line  from  point  to  point,  or 


Fig.  14. — Template  or  mould-frame 
for  ditcli. 


Fig.  13.— Ditchiug- 
spades. 


are  intermittent.     In  either  case  they  should  stop  a  few  feet 
from  the  boundary  marks. 

The  earth  dug  out  of  the  ditches  should  be  placed  on  the 
forest  side  of  the  ditch  and  a  few  feet  from  it  (Fig.  9),  or  in 


Figs.  15  and  16.— Bouudarj-ditch  serving  as  a  drain. 

the  case  of  intermittent  ditches  it  may  be  placed  between  them 
as  shown  in  Fig.  12. 

Intermittent  ditches  (Figs.  11  and  12)  are  usual  on  sloping 
ground  to  prevent  the  formation  of  ravines. 

The  section  of  the  ditches  depends  on  the  nature  of  the  soil, 
but  is  generally  2 — 2^  feet  wide  at  the  top  and  8 — 10  inches 


FOREST   BOUNDARIES.  19 

at  the  bottom  and  the  same  depth.  The  boundary  Hne  may 
be  the  centre  of  the  ditch,  or  one  of  its  sides  ;  in  the  latter 
case  the  ditch  belongs  to  the  proprietor  on  whose  land  the 
earth  from  it  is  thrown,  which  is  generally  towards  the  forest. 
Special  kinds  of  spades  are  used  for  ditching,  as  shown  in 
Fig.  13. 

A  wooden  model  of  the  ditch-profile  is  also  useful  (Fig.  14), 
and  is  termed  template  or  mould-frame. 

In  case  the  ditches  are  also  used  as  drains,  care  must  be 
taken  not  to  allow  the  boundary  marks  to  be  undermined. 
Thus  the  arrangement  shown  in  Fig.  15  should  be  followed  to 
protect  the  boundary  marks  from  erosion,  and  not  that  shown 
in  Fig.  16. 

4.  Survey  of  Boundaries. 

The  best  survey  is  that  carried  out  by  the  theodolite  and  a 
chain,  or  measuring  staff,  but  for  preliminary  work  a  less 
accurate  instrument,  such  as  the  plane-table  or  prismatic 
compass,  will  suffice.  From  the  survey  a  boundary  map 
should  be  drawn  up,  the  usual  scale  of  such  maps  being  40 
or  50  inches  to  the  mile  in  Germany.  No  larger  scale  than 
25  inches  to  the  mile  is  usual  for  British  woodlands. 
These  maps  should  show  : — 

All  boundary  marks  with  their  numbers. 
The  course  of  the  boundary  lines. 

The  names  of  adjoining  properties,  and  the  nature  of 
their  cultivation,  or  otherwise. 

5.  Description  oj  Boundaries. 

This  should  be  prepared  in  a  tabular  form,  and  should  show  : 
Name  of  forest  and  of  proprietor. 
Names  of  adjoining  estates  and  of  their  proprietors. 
Current  number  and  nature  of  boundary  marks. 
Angle  at  each  corner  in  degrees,  minutes  and  seconds. 
Distance  from  one  mark  to  the  next,  both  horizontally  and 

along  the  surface  of  the  ground. 
Direction   of   boundary  line  from  mark  to   mark,  with 

reference  either  to  that  of  the  magnetic  needle  or  true 

north. 

c  2 


20  PROTECTION   AGAINST   MAN. 

Other  remarks  worth  recording  should  be  added,  such  as 
crossing-points  of  streams,  roads  and  rights-of-way,  or 
reference  to  any  permanent  objects  near  tlie  line,  such 
as  trigonometrical  pillars,  etc. 

6.   Ij('[iaUsation  of  Boundaries. 

It  is  desirable  to  cause  the  boundary  map  and  description 
to  be  recognised  by  the  proper  State  authority,  according  to 
the  law  in  force.  The  original  documents  should  be  deposited 
in  the  State  Registry  Office  and  certificated  copies  given  to  the 
owners  of  the  two  adjoining  estates. 

7.   Upkeep  of  Boundaries. 

Forest,  boundar}-  lines  and  marks  are  liable  to  various  injuries 
by  men  and  animals,  and  by  the  weather.  When  once  laid 
down  they  must  be  maintained  in  good  order  ;  the  following 
measures  being  specially  necessary  : — 

(a)  Periodic  clearing  of  the  boundary  line,  so  that  one  mark 
may  be  visible  from  the  next.  In  case  the  boundary  line  be  a 
road,  bridle-path  or  ditch,  repairs  to  these  become  necessary 
from  time  to  time.  Any  vegetation  that  is  removed  should  be 
shared  between  the  adjacent  owners. 

(6)  Periodic  inspection  of  the  lines  by  the  forest  officials, 
to  whose  charge  definite  lengths  of  boundary  should  be  allotted, 
according  to  their  rank,  and  each  official  should  from  time  to 
time  submit  reports  to  his  superiors  on  the  condition  of  the 
boundaries. 

(c)  Wherever  woodlands  border  on  agricultural  land,  the 
trees  must  not  overshade  the  latter  with  their  foliage,  nor 
their  roots  grow  into  the  fields.  Drip  from  the  branches 
should  noj;  go  beyond  the  actual  boundary  line,  and  a  space 
should  be  kept  free  from  woody  growth,  the  actual  breadth  of 
which  varies  according  to  local  law.  As  a  rule,  the  neighbour 
can  lop  an  overhanging  tree  only  if  the  owner  of  the  woodland 
has  neglected  to  do  so ;  the  loppings  belong  to  the  latter. 
Intrusive  roots  may  usually  be  cut  by  the  neighbour.  Law- 
books should  be  consulted  on  this  question. 


FOREST    BOUNDARIES.  21 

(d)  Immediate  repaii'  of  all  defects  in  tlie  marks,  repainting 
fading  numbers,  etc.,  before  any  point  becomes  doubtful. 
Marks  which  may  have  been  removed  can  be  replaced  only 
with  the  consent  of  l)oth  owners  or  by  order  of  a  Court  of  Law. 
Any  uncertainty  about  the  position  of  forest  boundary  marks, 
that  are  also  boundary  marks  of  adjoining  States,  gives  rise  to 
much  difldculty. 

(e)  Immediate  report  of  all  tampering  with  established 
boundaries  and  prosecution  of  the  offenders. 

8.  Cost. 

The  cost  of  erecting  and  maintaining  forest  boundaries 
should  be  divided  between  the  adjacent  owners,  unless  there  is 
any  legal  provision  to  the  contrary. 

These  costs  vary  so  much  according  to  circumstances,  that 
it  is  difttcult  to  lay  down  any  general  estimates  ;  the  following 
figures  may  be  considered  approximate.  One  man  can  erect 
in  one  day  an  earth  boundary  mound  4  to  5  feet  in  diameter 
and  3  to  4  feet  high,  and  can  sod  about  3  to  6  such  mounds, 
and  repair  from  6  to  9  of  them. 

Hewn  limestone  boundary  stones  cost  2  to  3  shillings 
each,  and  20  such  stones  can  be  carted  by  two  horses.  Iron 
boundary  posts  cost  from  Is.  Cul.  to  2.s.  C)d.  each. 

In  loam,  a  man  can  dig  in  one  day  30  to  40  yards  of  boundary 
trench,  10  inches  wide  at  the  base,  and  of  the  same  depth.  In 
light  soils,  the  labour  is  from  10  to  15  per  cent,  heavier. 

Boundary  works  are  generally  done  by  contract,  and  on  the 
continent  of  Europe  repairs  to  forest  ditches  are  frequently 
executed  by  petty  offenders  in  lieu  of  fines. 


9.  Improvement  of  Boundaries. 

Advantage  should  be  taken  of  every  opportunity  to  consoli- 
date forest  property  and  thereby  to  improve  its  boundaries. 
This  can  be  done  by  purchase,  disposal  or  exchange  of  land, 
so  as  to  cut  olT  inconvenient  corners  or  narrow  strips,  to  alienate 
detached  pieces,  or  to  acquire  enclosures  belonging  to  other 
proprietors. 


22 


PROTECTION   AGAINST    MAN. 


Some  of  the  advantages  of  consolidation  are  : — 

(a)  Greater  facilit}"  for  keeping  the  boundary  hne  in  order, 
and  at  a  reduced  cost. 

(b)  Saving  in  protection  expenses,  in  work  of  stafif,  and  less 
liability  to  cases  of  misappropriation  and  damage  by  outsiders, 
esi^ecially  in  the  case  of  danger  from  lire. 

(c)  Increase  in  the  productiveness  of  the  forest.  Fewer 
roads  are  required ;  damage  is  reduced,  whether  it  is  caused 
to  the  forest  by  frost,  storms,  etc.,  or  to  adjoining  farm-land, 
by  overhanging  trees  or  by  game  sheltering  in  the  forest. 
Small  private  estates  enclosed  in  a  forest  frequently  encourage 
poaching,  or  unfair  destruction  of  game. 


Fig.  17.— IIo;i(l  of  Stoke  Tark  lU'd  Door  from  Mr.  Jtowbnul  Ward's  "  Records  of 


23 


CHAPTER  II. 

PROTECTION  OF  THE  FOREST  AGAINST  IRREGU- 
LARITIES IN  THE  UTILISATION  OF  FOREST 
PRODUCE. 

Section  I. — Principal  Produce. 
1.  General  Account  of  Damage  done. 

The  standing-crop  or  soil  of  a  forest  may  be  endangered 
during  fellings  and  in  the  conversion  and  transport  of  timber 
in  the  following  ways  : — By  overfelling,  bad  felling,  careless 
conversion  or  bad  stacking  of  timber  and  firewood,  and 
careless  transport. 

The  methods  for  fixing  the  annual  yield  of  a  forest  are 
explained  under  Forest  Manaffcnient,  and  how  timber  should 
be  felled  and  converted,  under  Forest  Utilisation  ;  here,  only 
the  preventive  measures  necessary  to  obviate  irregularities 
will  be  considered. 

Irregularities  of  wood-cutters,  cartmen,  etc.,  may  be  dealt 
with,  either  by  regulations  made  by  the  forest  owner,  or  by 
the  forest  laws  of  the  country. 

In  a  general  way,  it  should  be  noted  that  some  damage 
must  be  done  during  fellings,  conversion  and  transport,  and  it 
is  only  by  experience  that  a  forester  learns  how  much  damage 
is  unavoidable.  Too  stringent  conditions  should  not  be 
enforced  on  woodcutters  or  timber  purchasers. 

2.  Overfellinfj. 

All  forest  operations  must  be  carefully  watched,  and  their 
results  recorded,  so  that  only  the  fixed  yield  prescribed  by  the 
working-plan  is  cut  annually.  At  the  same  time,  at  least  in 
private  forests,  it  may  be  advisable  to  cut  more  than  the  fixed 
yield  in  seasons  when  the  price  of  timber  is  exceptionally  high, 
and  reduce  the  fellings  when  it  is  low. 


24-  PROTPXTION    A(;A1NST    MAN. 

In  order  to  keep  within  the  Hniits  of  the  fixed  annual  yield, 
trees  to  be  felled  should  be  properly  marked  in  accordance 
with  administrative  rules,  and  after  the  fellings,  the  stumj^s  of 
felled  trees  should  be  examined  and  counted  in  order  to  detect 
possible  irregularities.  In  some  cases,  as  in  Coppice-with- 
Standards,  the  trees  to  be  reserved  are  marked  instead  of 
those  to  be  felled.  The  practice  in  France  of  marking  such 
trees  by  cutting  off  a  portion  of  the  bark  and  stamping  on 
them  with  a  steel  hammer  may  give  rise  to  attacks  of  fungi 
and  defects  in  the  wood  at  the  base  of  the  tree. 

In  the  case  of  large  felling-areas,  it  may  be  necessary  to 
employ  an  extra  forest  guard,  in  addition  to  the  guard  of  the 
beat,  to  supervise  the  woodmen,  and  when  trees  are  sold 
standing,  the  purchaser  may  be  allowed  to  appoint  a  special 
guard  with  temporary  police  powers  and  a  badge  of  office. 
This  necessity  for  sj^ecial  supervision  applies  to  all  the  suc- 
ceeding sections,  referring  botli  to  the  removal  of  principal 
and  minor  produce. 

3.  Bad  FcUinfj. 

Measures  for  the  prevention  of  mischief  are  : — 

(a)  Employment  of  competent  and  trustworthy  woodcutters, 
and  careful  instruction  in,  and  supervision  of,  their  work.  It 
is  generally  advisable  to  employ  the  same  men  year  after  year, 
and  withdraw  from  the  gang  all  those  who  fell  badly,  also  to 
encourage  the  best  men  by  instruction  and  higher  wages. 
The  best  available  implements  should  be  used. 

(6)  Only  such  trees  should  l)e  felled,  as  are  so  designated 
by  the  manager  of  the  forest.  Should  any  other  tree  be 
accidentally  thrown,  owing  to  a  falling  tree  coming  against  it, 
a  neighbouring  tree  of  similar  dimensions  and  species  should 
be  left  to  replace  it. 

(r)  Trees  should  be  uprooted,  whenever  this  is  possible, 
and  felling  so  conducted  as  to  facilitate  the  transport  of  the 
timber. 

(f7)  Cessation  of  the  work  during  unfavourable  seasons  or 
weather  ;  for  instance,  when  the  trees  are  in  sap,  except  where 
bark  is  being  harvested  ;  during  absence  of  snow  on  the  ground 
to  break  the  fall  of  the  trees  and  spare  natural  regeneration  ; 


T.iT\ -»«*»' 


IRREGULARITIES    IN    UTILISATION.  25 

during  seasons  of  hard  frost,  when  the  stems  ma}^  be  broken, 
or  during  strong  winds,  when  the  direction  of  the  fall  of  the 
trees  is  uncertain.  In  northern  India,  felHngs  are  frequently 
stopped  during  the  hot  dry  months  of  May  and  June,  from 
fear  of  forest  fires  which  may  be  caused  by  the  workmen. 

(e)  Avoidance  of  damage  to  seedbearing  trees  in  regenera- 
tion fellings,  and  to  standards. 

(/)  Throwing  trees  on  to  bare  spots  and  not  amongst  young 
growth. 

{[/)  Eemoval  of  branches  and  crowns  of  trees  before  felling, 
to  prevent  the  trees  from  crushing  valuable  undergrowth. 

(h)  Preservation  of  young  growth  during  the  removal  of 
stumps,  and  putting  earth  into  holes  thus  caused  to  prevent 
their  being  filled  with  water. 

(0  Careful  felling  of  coppice  with  sharp  instruments  and 
with  a  clean  and  sloping  cut. 

(;■)  Leaving  stools  on  steep  slopes  where  erosion  is  to  be 
feared,  and  also  on  shifting  sands. 

(A-)  Avoidance  of  throwing  felled  trees  on  to  rocks,  stones  or 
other  stems ;  felling  uphill  or  sideways  so  that  there  may  be 
a  minimum  of  breakage. 

(Z)  Tropical  woody  climbers  should  be  cut  two  years  before 
a  felling  is  to  take  place,  as  otherwise  they  bind  trees 
together,  and  the  fall  of  any  tree  may  involve  that  of  a  group 
of*  surrounding  ones.  The  softwooded  climbers  rot  in  about 
two  years'  time. 

(m)  Trees  are  sometimes,  as  in  the  case  of  teak  in  Burma, 
girdled  two  or  three  years  before  being  felled,  so  that  the  wood 
may  dry  and  lose  weight,  and  become  floatable.  Care  must 
be  taken  that  this  is  not  done  to  trees  liable  after  girdling  to 
be  bored  by  insects. 

4.  Careless  Conversion. 

Here  may  be  mentioned  : — 

(a)  Quick  conversion  and  removal  of  felled  trees,  especially 
in  the  case  of  natural  regeneration  and  of  copj)ice ;  protection 
of  young  growth  in  both  cases. 

{h)  Use  of  the  saw  instead  of  the  axe  in  order  to  prevent  waste. 

(c)  Quick  removal  of  l)ark  to  prevent  insect-attacks. 


26  PROTECTION    AGAINST    MAN. 

{(J)  Repairs  of  ai\y  damage  done  to  young  plants,  which,  if 
of  broadleaved  species,  may,  when  injured,  be  cut  back  close 
to  the  ground  so  as  to  get  a  strong  regrowth.  Otherwise, 
replanting  must  be  effected  with  strong  transplants  after  the 
felling-area  has  been  cleared. 

5.  Bad  Stacking  of  TimJxn'  and  Fireuood. 

Employ  specially  trained  men  for  stacking  ilrewood,  as 
ordinary  woodcutters  generally  stack  loosely. 

Stacking  should  be  done  on  blanks,  or  along  the  edges  of 
felling-areas,  on  roadsides,  etc.  The  stacks  should  not  lean 
against  trees. 

Withes  for  binding  faggots  should  be  cut  from  suppressed 
stems,  or  taken  from  cleanings  or  special  plantations. 

6.  Careless  Transporl  of  Timber  and  Firewood. 

Attend  to  the  timely  construction  and  repairs  of  the  neces- 
sary roads,  slides,  etc.,  which  should  be  ready  when  the 
fellings  commence.  This  is  specially  requisite  in  mountain 
forests. 

Remove  material  from  the  felling-area  at  favourable  seasons, 
when  snow  is  on  the  ground ;  not  in  hard  frosts,  nor  when  the 
trees  are  in  sap  and  the  bark  of  standing  trees  is  easily  abraded 
by  the  wheels  of  the  carts,  etc. 

Avoid  damaging  methods,  such  as  rolHng,  etc.,  among  young 
growth.  Use  the  best  methods  of  transport :  slides,  tramways, 
etc.     INIake  good  roads. 

Fix  a  period  during  which  the  material  must  be  removed, 
say  from  November  of  one  year  to  the  end  of  winter  in  the 
next,  so  that  the  ground  may  be  cleared  in  time  for  the  spring- 
growth  of  the  second  year.  At  the  end  of  this  period,  all 
injured  broadleaved  plants  should  be  cut  ])ack,  blanks  planted 
up,  and  all  ruts  on  temporary  cart-tracks  filled  in. 

Certain  rules  should  be  made  for  the  protection  of  roads  and 
other  means  of  transport.  For  instance,  new  roads  should 
not  be  used  until  the  earth  has  settled,  and  they  have,  if 
possible,  been  macadamised.  Notices  closing  roads  under 
construction    or   repair    should    be   posted   up,  and   bars  put 


IRREGULARITIES    IN    UTILISATION.  27 

across  such  roads.     Dragging  along  ordinary  roads  should  be 
disallowed. 

All  transport  should  be  carefully  supervised,  if  necessary,  by 
extra  forest  guards. 

Section  II. — Irregulakities  in  utilising  Minor  Forest 
Produce. 

1.  General  Account  of  Damage  done. 

Whenever  the  minor  produce  is  less  important  than  the 
princii^al  produce  of  a  forest,  it  should  be  harvested  in  such  a 
way  as  not  to  endanger  or  diminish  the  supply  of  the  latter. 
The  following  are  the  chief  items  of  minor  forest  produce  : — 
Bark,  turpentine,  resin  and  gums,  leaves,  fruits  of  forest  trees, 
dead  branch-wood,  grass  and  lierhage,  litter,  stones,  gravel,  sand 
and  earth,  peat,  forest  cultivation  of  cereah,  berries,  edible  fungi, 
game,  fish,  ivild  honey  and  wax,  etc.,  etc. 

2.  Bark. 

Bark  is  chieflj'  used  for  tanning,  or  for  dyes,  but  the  bark 
of  certain  species,  such  as  the  paper-mulberry  {Broussonetia 
papyrifcra),  may  be  made  into  paper-pulp,  or,  as  in  the  case 
of  Betula  Bhojpalra  in  India,  into  hats  and  umbrellas.  The 
inner  bark  of  the  lime  and  of  many  tropical  trees  is  used  for 
rope-making  or  mats. 

In  the  case  of  oak-bark  used  for  tanning,  the  following  rules 
should  be  observed : — 

(a)  Secure  a  clean  and  slanting  cut  of  the  stems  in  order  to 
protect  the  stools  against  moisture,  and  produce  good  coppice 
shoots. 

(6)  Prevent  any  tearing  of  bark  from  the  stool,  by  making  a 
clean  cut  round  the  shoot  near  the  ground  before  the  bark  is 
peeled  from  standing  poles. 

(c)  Avoid  beating  the  bark  in  peeling,  as  this  causes  loss  of 
tannin. 

{d)  Eemove  peeled  stems  expeditiously,  so  that  the  new 
shoots  may  harden  before  early  frosts  occur. 

(t)  Carefully  stack  and  quickly  dry  the  bark,  so  as  to  avoid 


28  PROTECTION    AGAINST    MAN. 

loss  of   tannin  l)y  rain,  and  ensure  rapid  clearance  of   the 
felling-area. 

Wherever  bark  is  used  for  any  of  the  other  purposes  above 
referred  to,  similar  rules,  modified  for  the  species  in  question, 
should  be  observed. 

3.   Turpentine,  Resin  and  Gums. 

The  present  chief  sources  of  the  supply  of  turpentine  and 
resin  are  the  pitch  pine  {P.pahstris,  Mill.)  and  other  pine-trees 
in  the  Southern  States  of  North  America,  and  the  cluster  pine 
{Pinus  Pinaster,  Aitm.)  forests  in  the  west  of  France.  Tappings 
for  turpentine  and  resin  on  a  moderate  scale  have,  however,  been 
started  in  the  forests  of  the  long-needled  pine  of  the  Himalayas 
{P.  longifoUa,B.oxh.).  Some  turpentine  is  siill  obtained  from 
the  spruce  in  Germany  and  the  north  of  Europe,  but  as  this  tree 
only  yields  it  in  small  quantities  and  the  process  of  tapping  it 
is  extremely  injurious  to  spruce  timber,  its  tapping  should  be 
absolutely  prohibited. 

The  following  remarks,  therefore,  apply  only  to  species  of 
pine  which  yield  turpentine  abundantly,  and  to  the  extraction 
of  gums  and  caoutchouc  from  several  species  of  trees  in  hot 
countries. 

(a)  Lessees  of  turpentine  or  gum  should  be  held  pecuniarily 
responsible  for  all  damage  done  in  forests  by  their  workmen. 

(/>)  TajDping  sliould  generally  be  confined  either  to  trees 
like  theFicus  elastira,  Blume.,that  are  hardly  of  any  value  except 
for  the  gum  they  yield,  or  to  trees  too  remote  from  means 
of  transport  for  their  timber  to  be  of  any  marketable  value 
as  compared  with  the  value  of  the  turpentine  or  gum  which 
may  be  extracted  from  them.  In  other  cases,  it  should  be 
confined  to  trees  which  will  be  felled  for  timber  within  a 
period  of  from  ten  to  twenty  years,  as  when  young  trees  are 
tapped  no  considerable  increment  of  growth  may  l)e  expected. 
For  the  same  reason  the  best  shaped  and  most  promising  trees 
should  not  be  tapped. 

In  seeding-fellings,  a  certain  number  of  the  seed-bearers 
should  remain  untapped,  as  tapping  is  prejudicial  to  both  the 
quantity  and  quality  of  the  seed.  In  the  cluster  pine  forests 
of  the  Landes,  in   France,  regeneration   is  effected  by  seed 


IRREGULARITIES    IN    UTILISATION.  29 

from  untapped  woods  adjoining  the  felling-area  on  which  all 
trees  are  tapped. 

(c)  Eules  regarding  the  size  and  number  of  cuts  and  the 
depth  of  cut  to  be  made  in  each  tree  will  vary  with  the  species, 
and  are  given  in  detail  in  Vol.  V.  on  Forest  Utilisation.  In 
tapping  pines  for  resin,  there  should  not  be  more  than  two 
points  of  attack,  unless  it  is  intended  to  kill  the  tree,  when 
as  many  as  six  may  be  opened.  There  should  be  from  8  to  12 
inches  between  each  cut,  and  the  cuts  should  not  be  more  than 
2  inches  broad  and  in  one  year  only  about  3  feet  long. 

((/)  Tapping  must  be  intermittent,  so  as  to  allow  recovery 
of  the  trees  before  a  fresh  tapping  is  allowed,  unless  it  is 
intended  to  tap  the  tree  to  death  before  felling  it.  The 
interval  between  successive  tappings  will  of  course  vary  with 
the  species  in  question.  In  Europe,  all  tapping  should  cease 
with  the  first  early  frost  in  August  or  September,  and  not  be 
resumed  till  the  spring. 

(e)  Tapping  should  rarely  be  attempted  on  poor  soils. 

4.  Leaves  and  Branches  of  Forest  Trees. 

Leaves  of  forest  trees  are  used  ior  fodder,  manure,  thatching, 
tanning,  dyes,  etc.  Leaf-fodder  is  extensively  used  for  cattle 
in  countries  where  sufficient  grass  is  not  available,  as  in  the 
centre  and  south  of  France,  where  hedge-row  oaks  are 
annually  pollarded  for  this  purpose.  A  similar  practice  pre- 
vails in  the  Himalayan  districts  of  India  during  winter, 
evergreen  oaks,  elms  and  species  of  Celtis,  Pninus,  etc.,  being 
thus  utilised.  During  the  season  of  rest,  leaves  of  evergreen 
trees  are  rich  in  reserve  nutrient  material,  and  afford  valuable 
fodder.  In  seasons  of  drought  in  Central  and  Western 
Europe,  as  in  1893,  leaf -fodder  from  hornbeam  and  other 
deciduous  trees  is  also  extensively  used  instead  of  grass. 

In  the  north  of  India,  camels,  bufi'aloes  and  elephants  are 
chiefly  fed  on  branches  and  leaves  of  trees  during  the  cold 
and  dry  seasons.  Oaks  and  other  forest  trees  were  formerly 
extensively  pollarded  in  European  deer-forests  to  afford  fodder 
for  the  deer,  which  ate  the  bark  of  these  branches  when  the 
ground  was  covered  with  snow. 


80  PROTECTION    AGAINST    MAN. 

Wherever  the  use  of  leaf-fodder  prevails,  the  important  points 
are :  -to  allow  trees  to  be  lopped  only  after  the  principal 
growth  of  the  year  is  over ;  to  restrict  lopping,  as  much  as 
possible,  to  inferior  species  of  little  or  no  value  as  timber 
trees,  and  to  prevent  the  lopping  of  trees  until  they  have 
attained  a  certain  size.  Wherever  the  restriction  is  practi- 
cable, only  side-shoots  should  be  lopped  and  the  leaders 
spared,  and  the  trees  lopped  only  every  third  year.  In 
timber  forests,  lopping  should,  if  possible,  be  restricted  to 
compartments  which  will  shortly  be  cut  over. 

Where  the  demands  for  leaf-fodder  are  large  and  cannot 
otherwise  be  met,  a  regular  system  of  pollarding  should  be 
introduced,  with  a  fixed  rotation,  the  length  of  which  will  be 
decided  by  local  experience. 

In  India  and  other  hot  countries,  the* foliage  of  woody 
climbers  may  l)e  used  for  leaf-fodder  to  the  actual  benefit 
of  the  forests.  In  certain  parts  of  India,  green  branches  and 
leaves  of  trees  are  used  to  manure  the  rice-fields,  under  the 
term  of  rah ;  this  subject  will  be  referred  to  again  under  the 
heading  Forest  Servitudes.  In  hot  countries,  leaves  of  various 
forest  species  are  used  for  tanning,  dyes,  drugs,  hat-  and 
umbrella-making,  plates,  and  for  feeding  silkworms.  The 
last  is  a  very  important  and  valuable  industry,  and  the  trees 
utilised  are  generally  of  much  less  value  for  timber  than  for 
their  leaves,  and  therefore  rules  should  be  made  which  will 
afford  the  greatest  possible  quantity  of  leaves  at  the  time 
required,  and  in  a  way  most  easily  accessible  to  the  silk 
producers.  Thus  pure  coppice  is  adopted  with  very  short 
rotations,  even  of  one  year  in  the  case  of  the  mulberry  in 
Bengal.  As  regards  the  other  demands  for  leaves,  forest 
officers  would  do  well  not  to  be  pedantic  in  stopping  industries 
dependent  on  their  forests  which  can  be  supplied  without 
serious  injury  to  the  trees  by  the  exercise  of  a  little  ingenuity 
and  suitable  control. 

5.  Fruits  of  Forest  'Trees. 

Fruits  of  forest  trees  are  collected  for  sowing ;  for  the  food 
of  men  or  animals  ;  for  extracting  oil,  dj'es,  tannin,  etc. :  or 


PANNAGE.  31 

they  may  be  eaten  on  the  ground  in  the  forest  by  swine 
(pannage),  or  by  deer.  The  rules  for  the  protection  oL  the 
forest  are  as  follows  : — 

A.  Collection  by  Hand. 

Where  regeneration  by  seed  is  expected,  or  where  swine  or 
deer  are  to  be  fed  in  a  forest,  fruits  should  not  be  collected 
for  other  purposes.  Acorns  when  eaten  in  large  quantities 
are  poisonous  to  young  cattle.  Beasts  over  thtee  years  old  are 
seldom  thus  affected.  Hence,  the  collection  of  acorns  in 
forests  open  to  pasture  is  most  beneficial,  and  they  may  be 
used  advantageously  for  feeding  domestic  pigs. 

Forest  guards  must  watch  most  assiduously  during  the 
fruit-collecting  season. 

All  injuries  to  the  trees  during  the  collection  of  the  seed 
must  be  strictly  forbidden.  These  are  :  beating  trees  with 
axes;  dragging  down  fruit-laden  branches;  use  of  climbing- 
irons,  etc.  The  bad  effects  of  the  latter  on  the  quality  of  the 
wood  may  be  seen  from  Fig.  18,  each  wound  made  by  the  iron 
introducing  decay  into  the  timber.  Smooth-barked  species 
such  as  beech  and  Weymouth  pine  suffer  most  in  this  way ; 
so  does  the  sweet  chestnut. 

The  work  must  be  stopped  during  frost,  when  the  branches 
are  easily  broken. 

B.  Pannage. 

Pannage,  or  the  feeding  of  swine  on  the  mast  of  a  forest, 
consisting  of  fallen  acorns,  beech-nuts,  chestnuts,  etc.,  was 
formerly  a  very  important  industry,  but  is  now  becoming  less 
frequent  in  the  forests  of  Europe.  It  still  prevails  in  the  New 
Forest,  where  about  5,000  pigs  are  turned  into  the  woods  in 
good  mast-years,  from  the  14th  Sept.  to  the  8th  Nov. 

Swine  damage  forests  in  the  following  ways : — 

(a)  Eating-up  mast  in  seeding-fellings. 

{b)  Uprooting  young  plants,  breaking  off  weak  stems, 
abrading  the  bark  oft"  poles,  and  exposing  and  gnawing  roots 
of  valuable  forest  species.  All  these  injuries  are  chiefly  felt 
in  natural  regeneration-fellings,  and  in  thinnings  in  young 
woods,  on  loose  sandy  or  shallow  soils,  on  steep  slopes,  etc. 


82 


PROTECTION    AGAINST    MAN. 


Swine  are  useful  to  forests  in  the  preparation  of  the  soil 
for  Seed,  by  removing  the  covering  of  dead  leaves  and  ex- 
posing the  mineral  soil,  and  by  burying  acorns  and  other 
fruits ;  also  by  tramphng  dead  leaves  into  the  soil,  which  is 
of  importance  in  places  exposed  to  winds,  and  by  destroying 
mice  and  certain  insects  hibernating  or  moving  in  the 
soil-covering. 


Fig.  18.— Section  of  a  Scot 


(rt)  Points  of  injury. 

(6)  Concave  annual  rings  of  wood  occluding  wounds. 

(c)  Brown-coloured  wood  below  the  wounds,  showing  consequent  decay. 

The  protective  rules  for  pannage  are : — 

(a)  Exclusion  from  the  following  places :  Seeding-fellings, 
except  when  seed  is  very  abundant;  dry  loose  soils  in  the 
case  of  swine  driven  in  to  feed  exclusively  on  fungi,  worms, 
insects,  etc. ;  places  where  the  mast  is  reserved  for  deer  or 
wild  pigs. 

(h)  Compartments  opened  for  pannage  should  as  nearly  as 
possible  adjoin  one  another,  so  that  the  swine  may  not 
wander  uselessly  through  the  forest.  They  should  not  be 
allowed  to  remain  long  in  compartments  without  mast,  as 
they  then  proceed  to  bark  the  trees. 


•  GRASS-CUTTING.  8.'i 

(c)  The  place  wliere  the  swine  pass  the  night  should  he 
carefully  selected.  In  such  places  scarcely  a  root  escapes 
injury. 

{(I)  The  numher  of  swine  to  be  allowed  in  a  forest  must 
dei)end  on  the  quantity  of  mast  available.  Each  full-grown 
animal  requires  from  two-and-a-half  to  seven-and-a-half 
acres  of  forest. 

{(')  Limitation  of  pannage  to  the  period  of  the  year  from 
the  middle  of  October  till  the  end  of  January.  It  should  not 
commence  till  sufficient  mast  has  fallen,  as  otherwise  the 
swine  become  thin  from  much  wandering  about,  are  not 
easily  kept  together,  and  do  much  mischief.  On  the  other 
hand,  it  must  cease  when  the  mast  is  no  longer  sufficiently 
plentiful,  and  it  is  in  the  spring  that  the  greatest  damage  is 
done  by  peeling  the  bark  and  roots.  During  the  aftermast, 
after  Christmas,  the  acorns  become  more  digestible,  and  are 
specially  suitable  for  breeding- animals. 

if)  The  admission  of  swine  into  a  forest  should  be  granted 
only  on  condition  that  they  are  perfectly  healthy,  and  guarded 
by  trustworthy  swineherds  ;  two  hundred  swine  for  each  man, 
and  an  assistant  for  every  hundred  additional  swine. 

((/)  The  owners  of  the  swine  should  be  made  collectively 
responsible  for  all  damage  which  may  be  done  to  the  forest. 
In  Epping  Forest  all  swine  admitted  to  pannage  are  ringed. 


6.  Grass  and  Herbage. 

Grass  and  herbage,  dry  ferns,  heather,  etc.,  may  either  be 
cut  and  removed  from  the  forest  and  used  for  fodder  or  litter 
for  cattle,  or,  with  the  exception  of  the  ferns,  may  be  utilised 
on  the  spot  as  pasture  by  grazing  animals. 


A.   Grass-cutting. 

Grass  and  herbage  may  be  cut  for  fodder,  or  to  form 
thatching  material,  paper-pulp,  etc.  Dead  ferns,  especially 
bracken,  are  largely  used  for  litter,  and  heather  for  litter  or 
thatching. 


3*  PROTECTION    AGAINST    MAN. 

The  protective  rules  are  : — 

(1)  Limitation  to  persons  who  have  obtained  a  formal 
permit  from  the  forest  manager,  and,  as  a  general  rule,  on 
certain  fixed  daj^s,  when  the  forest  guards  can  supervise  the 
cutting. 

When  a  numl)er  of  people  are  together  cutting  herbage  in 
the  forest,  they  should  be  held  collectively  responsible  for  any 
damage  which  may  be  done. 

(2)  Restriction  of  cutting  to  places  with  a  moist  fertile  soil, 
which  can  bear  the  removal  of  the  mineral  constituents  of 
the  grass,  etc.  In  such  places,  planting  in  lines  between 
which  grass  can  easily  be  cut  is  more  suitable  than  natural 
regeneration.  In  some  cases,  heather  and  broom  protect 
young  plants  from  frost  and  insolation  and  should  be  left 
intact.  High  grass,  on  the  contrary,  as  will  be  seen  further 
on,  greatly  increases  radiation,  the  intensity  of  frost  and  the 
drying-up  of  the  soil  by  the  sun,  so  that  it  is  frequently  more 
advantageous  to  have  it  removed.  Its  removal  also  furnishes 
additional  security  against  forest  fires. 

(3)  The  use  of  scythes  should  not  be  permitted  amongst 
young  growth,  where  grass  should  be  cut  with  sickles  or 
pulled  up  by  hand.  In  India,  a  flat  cutting-instrument  called 
a  khurpa  is  frequently  used  by  grass-cutters  to  scrape  out  the 
rhizomes  of  the  grass,  which  are  highly  nutritious ;  this 
practice  should  not  be  allowed  in  forests.  Scythes  may  be 
used  in  older  plantations,  but  on  the  condition  of  leaving  a 
narrow  zone  of  grass  round  each  plant.  On  rides,  extensive 
blanks,  road-sides,  etc.,  there  need  be  no  restriction  as  regards 
the  instruments  used  for  grass-cutting. 

(4)  In  hot  countries,  grass  which  springs  up  after  forests 
have  been  burned  furnishes  better  thatch  or  paper-material 
than  when  cut  from  unburned  forest  containing  much  dead 
and  decayed  grass,  dead  leaves,  etc.  Hence,  in  forests  under 
fire  protection,  grass  can  be  used  with  advantage  only 
from  off  roads,  fire-traces  or  blanks  which  are  cut  every 
year. 

(5)  Grass-cutting  must  be  carefully  supervised  by  forest- 
guards,  and  offenders  against  the  rules  reported  and 
punished. 


FOREST    PASTURE.  85 

B.    Forest  Pasture.* 
(1)   General  Account. 

Forest  pasture,  except  in  mountainous  districts,  where  the 
area  of  cultivable  land  is  very  limited,  is  no  longer  so  impor- 
tant as  was  formerly  the  case  ;  cultivators  object  to  their  cattle 
becoming  thin  and  wiry  in  roaming  about  the  forests,  to  their 
cows  yielding  less  milk  than  when  kept  at  home,  to  the  loss  of 
valuable  manure,  and  to  the  increased  danger  from  disease. 

In  backward  countries,  however,  forest  pasture  is  still  pre- 
valent, and  it  is  therefore  necessary  to  draw  up  rules  for  its 
exercise  with  the  least  possible  amount  of  injury  to  forests, 
as,  when  unrestricted,  it  is  incompatible  with  the  existence  of 
forests.  To  a  certain  extent,  however,  some  good  may  be 
done  to  forests  by  cattle,  by  keeping  down  a  rank  growth  of 
grass  and  herbage,  which  interferes  with  reproduction,  and 
by  breaking  through  and  scattering  the  dense  layer  of  needles 
in  coniferous  forests,  and  thus  exposing  the  mineral  soil  for  the 
rooting  of  seedlings.  Browsing  on  advance-growth  of  subsidiary 
species  or  softwoods,  which  it  is  desirable  to  keep  in  check  in 
favour  of  more  valuable  species,  may  also  be  sometimes 
useful. t 

The  damage  done  to  forests  by  the  grazing  and  browsing  of 
domestic  animals  extends  to  the  soil,  especially  on  slopes,  and 
standing-crop ;  to  the  roads  and  other  means  of  communication, 
and  the  boundaries,  ditches,  fences,  etc. 

The  soil  of  a  forest  suffers  chemically,  becoming  impoverished 
in  potash,  phosphorus,  and  nitrogen  by  the  removal  of  the 
grass ;  and  physically,  becoming  hardened  owing  to  the 
tread  of  the  grazing  animals,  and  the  consequent  insufficient 
aeration  of  the  humus  in  process  of  formation.  The  dung 
left  by  the  animals  on  the  ground  is  a  quite  inadequate  com- 
pensation for  the  reduction  in  fertility  of  the  soil  consequent 
on  their  admission  to  the  forest.     Tlie  woods  are  injured  in 

*  Hundeshagen,  J.  C,  "Die  Waldvvcide  u.  Waldstreu."    Tubingen,  1830. 

t  In  "Forest  Utilisation,"  p.  137,  Fernandez  states  that  goats  are  useful  to 
regeneration  in  mature  Acacia  arahica  [babul)  forests.  Wlien  the  pods  are 
falling,  the  seeds  swallowed  by  the  goats  and  excreted  germinate  without  delay, 
whilst  other  seeds  require  at  least  a  whole  year  to  sprout,  during  which  they  are 
exposed  to  destruction,  chiefly  by  insects. 

D    2 


86  PROTECTION    AGAINST    MAN. 

tlie  following  ways  :  by  the  animals  browsing  on  young  plants  ; 
biting-off  buds,  leaves,  and  shoots ;  breaking-off  coppice-shoots 
and  gnawing  the  bark  of  trees ;  trampling  on,  bending  down 
and  breaking  young  growth ;  exposing  and  destroying  roots, 
etc.  The  damage  done  by  biting  the  })lants  is  twofold ;  they 
lose  organs  that  are  necessary  for  tlieir  nourishment,  while  the 
normal  development  of  their  stems  and  branches  is  prevented. 
Both  forms  of  injury  occur  chiefly  in  their  youth,  until 
their  leading  shoots  have  grown  beyond  the  reach  of  the 
animals. 

Roads,  ditches,  slopes,  hedges,  and  fences,  are  especially 
liable  to  injury  by  grazing  animals. 

The  extent  of  the  damage  done  by  grazing  depends  on  a 
number  of  factors.  Among  the  chief  of  these  are  : — Species 
of  tree,  age  of  tree ;  system  of  management,  nature  of  locality, 
density  of  crop,  species  of  grazing  animal,  number  of  animals, 
season  of  the  year,  state  of  the  weather.  The  amount  of 
damage  varies  greatly  according  to  circumstances.  Hundes- 
hagen*  estimates  the  ordinary  loss  of  increment  due  to  cattle- 
grazing  at  one-tenth.  In  Carinthia  it  has  been  observed  that 
goats  in  15-  to  35-years-old  spruce,  Scotch  pines  and  hornbeams 
prevent  almost  any  growth  from  taking  place. 

(2)  Accordbuj  to  Sj^ccics  of  Tree. 

Broadleaved  species  are  more  exposed  than  conifers,  but 
recover  more  readily  from  browsing  than  the  latter.  Most 
exi)osed  to  damage  are  :  ash,  maples,  hornbeam,  beech.  Next 
to  them  :  lime,  sallow,  and  poplars.  Less  still :  oaks,  elms, 
Pyrus  sp.  Least  of  all  :  birch,  alder,  horse-chestnut  and 
robinia. 

Of  conifers,  the  silver-fir  suffers  most,  then  larch,  the 
different  species  of  pine  and  the  spruce.  If  the  spruce 
appears  to  suffer  more  than  pines,  this  is  due  to  its  abundance 
in  mountain  regions,  where  there  is  most  forest  pasture. 

The  above  scale  is  drawn  up  chiefly  as  regards  horned 
cattle,  but  if    we   consider    the  preferences  shown  by  other 

•  "  Encyclopadie  der  Forstwisscnschaft."  I.  Fovstliche  I'lodiictimislelire,  3 
Aufl.     Tiihingen,  1835,  p.  ■>]2. 


FOREST    PASTURE.  37 

grazing  animals,  it  should  be  noted,  that: — ^hoi-ses  prefer  oak- 
foliage  and  avoid  that  of  the  lime  ;  sheep  appear  to  prefer 
light-demanding  species,  even  the  birch  and  Scots  pine ; 
young  lambs,  the  leaves  of  robinia ;  goats  are  not  particular, 
and  even  browse  on  the  poisonous  yew  without  injury,  in 
India,  however,  they  succumb  to  the  foliage  of  lihododcndron 
campanulatum. 

Another  peculiarity  of  horned  cattle  is  to  prefer  plants  intro- 
duced into  pure  woods,  such  as  ash  or  hornbeam  in  beech 
forests,  or  exotics  planted  among  native  woods. 

The  vegetable  monstrosities  resulting  from  browsing  are 
very  striking  to  the  eye ;  rounded  bushes,  which  sometimes 
broaden  out  till  some  leading  shoots  in  their  centre  escape  and 
grow  into  trees,  are  frequent  eyesores  wherever  forest  pasture 
is  practised. 

Shallow-rooted  plants  such  as  the  spruce,  in  spring,  suffer 
most  from  the  tread  of  the  animals. 

(3)  Age  of  Trees. 

Young  plants  suffer  most.  In  older  woods,  without  under- 
growth, the  chief  injury  is  done  by  the  hardening  of  the  soil 
owing  to  the  tread  of  the  animals.  The  trees  suffer  from 
browsing  until  the  foliage  is  beyond  the  reach  of  the  animals, 
and  the  age  at  which  this  happens  depends  on  the  rate  of 
growth,  the  conditions  of  the  locality  and  the  kind  of  animal. 

(4)  System  of  Management. 

In  the  case  of  the  Selection  system,  grazing  is  most  dangerous  ; 
then  come  in  descending  order  of  danger:  Groiq)  system, 
Copjnce-ivitJi- Standards,  Coppice,  Slielterwood  Compartment 
and  Clear-cutting  systems.  Pollarding  is  the  most  favourable 
system  to  adopt  on  land  open  to  grazing,  as  young  pollard- 
shoots  are  out  of  the  reach  of  the  cattle;  pollards  are 
regenerated  by  planting  taller  transplants,  or  cuttings,  than 
in  other  systems,  and  the  plants  should  at  first  be  securely 
fenced  against  cattle,  which  might  injure  them  by  rubbing 
against  them,  or  gnawing  their  bark.  The  uneven-aged 
systems  of  High  Forest,  such    as    the    Selection  and  Group 


38  PROTECTION    AGAINST    MAN. 

systems,  suffer  most  of  all,  as  in  the  former,  young  growth  is 
scattered  all  over  the  forest,  and  in  the  latter,  it  is  scattered 
in  patches  over  very  large  areas.  If  grazing  be  allowed  under 
the  Selection  system,  regeneration  can  usually  be  effected  only 
by  fencing-in  patches  of  ground  where  large  trees  have  been 
felled,  and  planting  them  with  strong  transplants,  which  will  be 
out  of  the  reach  of  the  cattle  by  the  time  the  fences  are  no 
longer  effectual. 

Coppice-with-standards  suffers  more  than  pure  coppice,  on 
account  of  the  necessity  for  preserving  numerous  seedling 
plants,  both  natural  and  transplanted,  to  replace  the  standards 
as  they  are  felled.  Coppice  suffers  more  than  even-aged  High 
Forest,  because  stool-shoots  branch  out  lower,  and  are  less 
firmly  rooted  than  High  Forest  poles ;  in  the  even-aged 
systems  of  High  Forest  all  pole- woods  can  be  opened  to 
cattle  without  much  danger.  In  regular  plantations,  damage 
done  by  grazing  is  less  than  in  irregular  artificial,  or  natural 
reproduction,  and  planting  in  lines  somewhat  far  apart  in  one 
direction  is  most  favourable,  as  the  cattle  can  readily  graze 
between  the  rows.  It  has  also  been  observed  in  grazed  forests 
in  hill-tracts,  that  mound-planting  gives  better  results  than 
pit-planting. 

Gayer  holds  an  opinion  differing  from  that  of  Hess  regarding 
the  comparative  immunity  of  Selection  Forest  and  even-aged 
High  Forest  from  grazing.  He  mahitains,  that  even-aged 
densely  stocked  woods  are  destitute  of  herbage,  which  is  found 
only  on  the  reproduction  areas  closed  against  cattle.  It  is  a 
matter  of  everyday  experience  that  no  amount  of  care  in 
fencing  will  always  protect  such  areas.  In  a  Selection  Forest, 
not  only  is  far  more  fodder  produced,  but  damage  by  cattle  is 
less  concentrated  than  in  even-aged  woods.* 

(5)  LocaUiy. 

On  moist  and  fertile  soil,  the  damage  done  by  grazing  is 
minimised,  because  a  strong  growth  of  herbage  generally 
springs  up  on  such  localities,  and  the  cattle  have  less  inclina- 
tion to  attack  woody  growth  ;  moreover  the  trees  grow  faster, 

*    Vidf  1).  r,27,  Vi.l.  V.uf  this  iiiimuul. 


FOREST   PASTURE.  30 

and  are  sooner  out  of  their  reach.  Binding  or  heavy  soil 
becomes  all  the  more  compact  by  the  tread  of  the  animals, 
and  less  susceptible  to  the  entrance  of  air  and  water,  and  the 
roots  lying  immediately  below  the  soil-covering  are  exposed 
to  damage.  Very  loose  soil  becomes  still  looser  from  the 
tread  of  cattle,  as  they  destroy  the  herbage  which  binds  the 
soil  together.  The  greatest  damage  by  grazing  animals  is  on 
shifting  sands. 

On  level  ground,  damage  is  less  than  among  hills,  where  it 
is  increased  if  the  soil  be  loose,  or  the  slopes  steep  ;  very  wet 
slopes  are  also  endangered  by  the  sliding  of  the  feet  of  the 
cattle.  The  steeper  a  slope,  up  to  a  certain  point,  the  more 
erosion  is  caused ;  larger  plants  are  also  reached  by  cattle 
from  above,  on  slopes,  than  on  level  ground,  and  the  damage 
by  browsing,  bending  and  breaking  is  greater. 

Scantily  wooded,  dry,  hot  aspects  are  obviously  unsuited  for 
grazing. 

(6)  Density  of  Foreign  Growth. 

In  dense  woods,  little  or  no  grass  is  to  be  found,  so  that 
more  damage  is  done  to  woody  growth  than  in  more  open 
forests,  where  herbage  grows  under  the  trees. 

(7)  Species  of  Grazing  Animal. 

Among  European  animals,  goats  show  the  greatest  prefer- 
ence for  woody  plants,  and  their  mode  of  feeding  is  most 
injurious.  They  even  devour  woody  plants  when  there  is 
plenty  of  herbage  available,  and  beat  down  saplings  with  their 
forelegs  till  they  can  reach  the  leading  shoots,  on  which  they 
browse ;  they  can  thus  reach  plants  12  feet  in  height.  They 
also  peel  the  bark  from  stems  in  spring.  Their  constant 
movement  on  the  steepest  slopes  is  another  great  source  of 
damage.  To  take  some  of  many  instances  of  the  destruction 
of  forests  by  goats  : — In  the  Tyrol  and  Southern  Switzerland, 
and  in  the  Himalayas,  fine  forests  have  been  completely 
destroj'ed  by  them,  and  in  Ajmere  and  Merwara,  whole  hill- 
sides where  vegetation  once  flourished  have  been  laid  almost 
bare,    with    nothing    left    but    deformed,  thorny   shrubs.     In 


40  PROTECTION    AOAINST    MAN. 

France,  since  1GG5,  goats  have  been  excluded  from  all  forests 
managed  by  the  State  Forest  Department,  and  no  legal  right 
can  be  enforced  to  graze  goats  in  private  forests,  as  the 
grazing  of  these  animals  is  considered  incompatible  with  the 
maintenance  of  underwood. 

The  slteep  is  less  injurious  than  the  goat,  holding  its  head 
low,  and  preferring  grass,  but  sheep  browse  freely  on  woody 
plants,  and  injure  forest  soil  and  the  roots  of  shallow-rooted 
species  by  their  short  tread  and  sharp  feet. 

Horned  cattle  generally  confine  themselves  to  grass  and 
herbage,  and  attack  woody  plants  only  in  the  absence  or 
scarcity  of  the  former.  The  buffalo  in  India  is  frequently  fed 
during  the  cold  season  on  loppings  of  evergreen  or  winter- 
green  trees.  Cattle  do  much  injury  to  forest  soil,  slopes,  roads, 
and  ditches  owing  to  their  weight  and  size,  and  also  break 
down  seedlings  and  saplings  ;  these  injuries  are  aggravated  in 
the  case  of  the  buffalo,  which  is  a  heavier  animal  than  common 
cattle.  Oxen  are  more  destructive  than  cows,  and  young  beasts 
are  worse  than  older  ones,  as  they  gnaw  woody  growth,  partly 
out  of  pure  mischief  and  partly  to  develop  the  formation  of 
their  teeth,  and  are  much  more  active. 

Horses  can  reach  higher,  and  are  fonder  of  leaf-fodder  than 
cattle,  and  do  much  damage  to  roots  by  their  tread.  Foals 
occasionally  peel  the  bark  from  trees.  I  have  seen  a  clump 
of  old  beech  trees  in  Cambridgeshire  killed  by  the  trampling 
of  horses,  which  sheltered  there  in  the  heat  of  the  day.  The 
trees  had  originally  been  fenced,  but  when  the  fence  had  been 
broken  the  trees  were  soon  killed. 

Camels  eat  almost  everything  that  grows  within  their  reach, 
to  a  considerable  height,  and  can  feed  readily  on  thorny  species 
owing  to  their  hard  mouths.  Much  damage  has  been  done  to 
forest  growth  by  camels  in  Northern  and  Central  India  and 
in  Central  Asia. 

Elei>hants  are  fed  chiefly  by  loppings  from  species  of  Ficus 
and  other  trees,  as  well  as  on  grass  and  herbage,  but  the 
number  of  tame  elephants  admitted  to  a  forest  is  limited,  and 
their  browsing  can  be  easily  controlled.  Wild  elephants  are 
very  destructive  in  bamboo  forests,  and  also  bark  trees  with 
their  tusks. 


FOREST    PASTURE.  41 

The  relative  damage  done  to  forests  by  European  grazing 
animals  has  been  estimated  as  follows  by  Hiindeshagen  : — 
Horse's  foal  .         ,         .150 

Horse  .         .         .         .100 

Young  cattle        ...       75 
Old  cattle    ....       50 

Goat 25 

Sheep  ....       15 

This  list  is  drawn  up  on  the  understanding  that  the  animals 
are  freely  grazing  in  forests  where  the  crowns  of  the  trees 
have  grown  beyond  their  reach.  The  fact  that  the  goat  is 
only  estimated  to  do  a  quarter  the  damage  of  the  horse  does 
not  controvert  the  former  statement  of  its  being  relatively  to 
its  size  the  most  harmful  beast,  for  its  weight  is  only  about 
l-14th  of  that  of  the  horse. 

(8)  Numbei-  of  Cattle  admitted  to  the  Forest. 

The  number  of  cattle  admitted  to  graze  in  a  forest  must  be 
regulated  by  the  species  and  amount  of  herbage  available ;  it 
should  be  so  fixed  that  the  latter  is  sufficient  to  nourish  the 
cattle,  or  else  they  are  certain  to  attack  the  trees. 

Hundeshagen  has  calculated  for  the  complete  nourishment 
of  large  milch  cattle  for  the  whole  summer,  night  and  day, 
that  10  to  12^  acres  of  good  pasture  is  required  ;  for  merely 
grazing  by  day,  2^ — 5  acres,  and  he  reckons  2  to  3  young 
cattle  or  10  sheep  as  equivalent  to  one  head  of  full-grown 
cattle.  He  estimates  for  their  daily  requirements,  18 — 20  lbs. 
of  hay  for  a  cow  weighing  four  hundredweight,  10  to  12^  lbs. 
per  head  of  young  cattle,  and  1^ — 2  lbs.  for  a  sheep.  In 
Switzerland,  one  cow  is  usually  reckoned  to  eat  as  much  as 
seven  slieep. 

(9)  Season  of  the  Year. 

In  Europe  the  greatest  amount  of  damage  is  done  to  forests 
by  grazing  in  the  spring,  when  the  young  leaves  and  shoots 
are  most  tempting  and  the  herbage  scanty.  The  strong 
appetite  and  restlessness  of  the  beasts  after  the  long  winter 
stalling  has  also  to  be  considered.     The  least  damage  is  done 


42  PROTECTION    AGAINST    MAN. 

ill  the  autumn,  l)ut  as  the  grass  at  that  season  is  hard  and 
unnutritious,  forest-jiasture  is  chiefly  used  when  the  herbage 
is  best  and  most  plentiful,  from  the  end  of  May  till  the  middle 
of  July. 

In  the  plains  and  lower  hills  of  extra-tropical  India,  forest 
grazing  is  chiefly  confined  to  the  cold  and  dry  seasons,  but 
varies  with  localities. 

In  the  Himalayas,  grazing  is  carried  on  in  the  upper  forests 
from  8,000  to  10,000  feet  above  sea-level,  between  May  and 
September,  the  animals  coming  down  in  the  cold  season  below 
the  snow-level. 

(10)  State  of  the   Weather. 

During  very  dry  or  very  wet  weather,  or  in  the  morning, 
while  heavy  dew  is  on  the  ground,  cattle  prefer  the  leaves  of 
trees  to  herbage.  The  damage  done  to  the  roots  of  trees  by 
the  tread  of  cattle  is  also  greatest  in  wet  weather. 

(11)   OtJier  Considerations. 

Milch  cattle  require  the  best  grazing  grounds,  and  those 
nearest  to  the  villages ;  then  come  young  cattle.  Beasts  of 
draught  can  go  further  and  put  up  with  inferior  pasture. 
Sheep  can  be  pastured  in  places  that  are  more  remote  from 
the  farmsteads  than  those  used  for  cattle  pasture. 

Horned  cattle  and  especially  buffaloes  like  moist  pastures, 
and  the  latter  will  eat  very  coarse  herbage.  Horses  prefer 
short  grass  on  old  roads  to  that  grown  on  loose  forest  soil. 
Sheep  prefer  even  drier  herbage,  in  elevated  lands  exposed  to 
full  light,  such  as  heather-land,  and  are  very  liable  to  disease 
if  fed  on  moister  lands. 

Horned  cattle  will  not  graze  readily  after  sheep,  and  attack 
woody  growth  in  preference  to  grass  where  sheep  have  been 
grazing. 

Cattle  accustomed  from  their  youth  to  forest  grazing  do 
more  damage  than  others  which  seldom  come  into  the  forest. 
Less  damage  is  done  w4ien  the  herds  are  kept  well  together, 
and  this  is  most  difficult  to  secure  in  the  case  of  goats  and 
easiest  with  sheep. 

AVlien  one  considers   all   tlie  various  circumstances  which 


FOREST    PASTURE.  43 

affect  the  damage  done  by  grazing,  it  is  not  surprising  that 
practical  foresters  should  differ  greatly  in  their  estimates  of 
its  amount  in  different  cases.  Whilst  a  forester  having  cop- 
pice-with-standards  to  deal  with  may  consider  the  amount  of 
damage  done  as  very  considerable,  another  in  charge  of  spruce 
forest  under  the  clear-cutting  system  may  look  upon  it  as 
quite  trifling. 

It  is,  however,  clear  from  the  experience  of  grazing  in 
so  man}'  mountain  forests  in  the  Harz,  Black  Forest,  etc., 
where  thousands  of  head  of  cattle  have  grazed  for  centuries, 
and  the  forests  are  still  flourishing,  that  well-regulated  forest 
grazing  may  be  admitted  wherever  its  necessity  for  the  welfare 
of  the  people  is  very  pressing;  a  great  resource  in  times  of 
drought  may  also  be  secured  to  the  people  by  opening  portions 
of  State  and  other  forests  for  pasture  at  such  seasons. 

Under  certain  circumstances,  where  the  ground  under  a 
seeding-felling  is  covered  with  tall  herbage,  or  a  dense  mass 
of  dead  leaves  and  moss,  temporary  driving-in  of  cattle  may 
prov«  useful,  and  also  in  the  case  of  a  plague  of  mice,  or  of 
insects,  when  their  larvae  or  pupae  are  on  the  ground. 

(12)   Protective  Measures. 

The  regulation  of  forest  pasture  may  be  considered  under 
the  headings : — close-time,  arrangement  of  grazing  areas,  season 
for  grazing,  species  of  animal,  number  of  animals,  control  and 
protective  staff. 

(/.  Close-time. 

Close-time  is  the  period  during  which  a  wood  should  not  be 
opened  to  grazing.  It  commences  with  the  regeneration  of 
the  wood,  and  terminates  when  the  young  trees  can  no  longer 
be  reached  by  the  animals,  in  the  pole  stage.  The  length  of 
the  close-time  depends  on  the  species  of  tree,  the  system  of 
management,  the  circumstances  of  the  locality,  and  the  kind 
of  gi-azing  animal. 

Broadleaved  species,  especially  slow-growing  ones,  require 
a  longer  close- time  than  conifers  ;  high  forests,  a  longer  close- 
time  than  coppice.  In  the  case  of  mixed  woods,  the  length 
of  the  close-time  will  depend  on  the  most  endangered  species. 


44. 


PROTECTION   AGAINST    MAN. 


On  poor  soil,  in  exposed  places,  longer  close-periods  are 
required  than  for  good  soils,  sheltered  positions,  and  mild 
climates,  since  trees  then  grow  faster.  Sheep  can  be  driven 
earlier  than  cattle  or  horses  into  a  forest. 

The  calculation  of  the  open  area  in  a  forest  is  given  in  the 
following  formula  : — 

Let  F  =  area  of  forest, 
/  =  closed  area, 
./"i  =  F  —  /  =  open  area, 
,s-  =  close-time, 
/•  =:  rotation  of  forest. 


Then,/=F^ 


For  example,  a  forest  of  1,000  acres  area,  with  a  rotation 
of  100  years,  and  a  close-time  of  25  years  : 

The  closed  area  =  1,000  :^  =  250  acres. 
The  open  area  —  1,000  ^  =  750  acres. 

Speaking  generally,  according  to  G.  L.  Ilartig,  the  following 

areas  should  be  closed  : — 

Broadleaved  forest     .         .         .  :^  to  ;^  of  the  whole  area. 
Coniferous       do.        .         .         •  ^^  to  ^  ,, 

Coppice  do.        ,         .         .  ^  to  |  ,, 

According  to  Hundeshagen,  the   close-time    should    be    as 

follows : — 

System  of  Management. 


Species 

of 
Cattle. 

Broadleaved 
High  Forest. 

Coniferous 
Forest. 

Coppice 

with 

Standards. 

Coppice. 

Horses      and 
horned  cattle 

Sheep  .     .     . 

Years. 

}  18-24 
14—18 

Years. 

12—20 
<l— IC) 

Years. 

14—18 
10—12 

Years. 

6—14 
4—10 

FOREST   PASTURE.  45 

In  this  table  the  minima  are  for  good  localities,  and  for 
species  not  much  endangered  by  grazing,  and  the  maxima  for 
inferior  localities,  and  for  species  preferred  by  the  animals. 

When  the  animals  are  simply  driven  through  a  forest, 
much  younger  woods  can  be  opened,  but  in  such  cases  the 
gradient  of  the  slopes  and  the  consistency  of  the  soil  should 
be  considered.  Thus,  in  the  Harz,  3-to-5-years-old  plantations 
of  spruce  with  appetising  grass  are  opened  to  cattle  and 
suffer  less  than  older  woods,  where  the  grass  is  hard  and 
unnutritious. 

b.  Lorafion  of  Grazing  Areas, 

Every  year  a  new  tabular  form  showing  the  areas  opened 
to  grazing  should  be  drawn  up  and  publicly  advertised  amongst 
the  grazing  villages  that  use  the  forest.  In  preparing  such  a 
form,  the  open  compartments  should  be  arranged  so  as  to 
make  it  possible  for  the  animals  to  pass  through  old  woods 
from  one  grazing  ground  to  the  next,  or  drift-roads  should  be 
laid-ou^  between  them  wherever  young  woods  intervene,  and 
sufficient  time  allowed  for  the  grass  to  grow  in  a  grazed  area 
before  its  turn  for  opening  recurs.  Marshy  places,  loose  soil 
and  steep  slopes  are  to  be  excluded.  Localities  with  under- 
growth that  is  valued  for  regeneration  must  not  be  opened  to 
sheep.  Where  trampling  is  to  be  dreaded,  horned  cattle  must 
also  be  excluded.  Attention  to  the  requirements  of  the  animals 
when  drawing  up  the  plan  of  grazing  will  also  tend  to  restrict 
damage. 

The  closed  areas  must  be  marked  on  the  ground  with  notice 
boards,  or  protected  witli  fences  or  ditches,  the  hitter  to  be 
3  feet  wide  and  1^  feet  deep,  with  the  earth  thrown  up  on  the 
side  of  the  closed  area. 

If  drift-roads  are  required  from  one  part  of  the  forest  to 
another,  they  should  be  from  15  to  24  feet  wide,  according  to 
the  number  and  species  of  grazing  animals.  Wherever  these 
roads  pass  through  very  young  growth,  ditches,  earth  or  stone 
walls,  or  dry  thorn  hedges,  should  be  placed  on  either  side. 
The  earth  from  the  ditches  should  be  thrown  up  towards  the 
closed  area  to  assist  in  keeping  out  the  cattle. 

Wherever  such  protective  works  are  not  made  along  a  drift 


46  PROTECTION    AGAINST    MAN. 

road,  the  nearest  rows  of  young  plants  should  he  protected,  as 
in  Fig.  20,  each  with  three  rough  stakes  with  the  jagged  sides 
pointing  outwards.  When  for  the  removal  of  a  strong  growth 
of  herhage,  or  other  reasons, 
pasture  in  young  growth  is  con- 
sidered advisable,  this  should  be 
allowed  only  from  the  1st  of  July 
after  the  year's  shoots  have  com- 
menced hardening,  and  in  dry 
weather.  By  multiple-planting 
at  each  spot,  in  threes  or  more, 

Fig.  19. — Protection  for  youn»  ,i  •  ,  - 

plants.  there  is  more  chance  of   success 

in  grazed  forests,  than  when 
single  plants  are  used.  In  grazed  selection  forests,  the  only 
certam  system  of  reproduction  is  to  plant  in  groups  where 
old  trees  have  been  removed,  and  fence-in  each  group  until 
the  plants  require  no  further  protection. 

r.  Durafion  of  Fashire. 

The  usual  duration  of  pasture  in  Europe  is  from  May  till 
September.  The  period  for  grazing  varies  in  different  coun- 
tries, being,  however,  much  the  same  in  the  mountainous 
parts  of  Northern  India  as  in  Europe.  In  hot  countries 
great  danger  arises  from  the  custom  of  firing  the  dry  grass 
in  forests  for  spring-grazing,  in  order  to  get  fresh  young  shoots 
from  the  rhizomes  of  the  grass,  as  the  dead  cold- weather  grass 
is  unnutritious.  In  certain  forests,  however,  some  of  the 
grasses  remain  green,  long  after  the  grass  outside  the  forests 
has  dried  up,  especially  when  the  forests  are  at  a  certain 
altitude  and  on  northern  aspects. 

Owing  to  unsuitability  of  the  unburned  grass  for  pasture, 
certain  inferior  areas  of  forest  and  blanks  may  have  to  be 
given  up  as  grazing-grounds,  and  burned  annually  for  this 
purpose.  It  is  found  by  experience,  that,  owing  to  constant 
grazing,  coarse  grasses  gradually  disappear  from  these  areas, 
so  that  eventually  they  need  not  he  burned,  the  non-inflam- 
mability of  the  finer  grasses  then  assists  in  the  protection  of 
the  valuable  parts  of  the  forest  from  fire.  It  is,  however, 
always  preferable  to  try  and   induce  the  people  to  cut  and 


FOREST    PASTURE.  47 

remove  the  grass  before  it  has  l)ecome  dried-iip,  and  preserve 
it  as  hay  or  ensilage  for  use  during  the  dry  season.  This 
plan  has  had  great  success  in  Ajmir,  in  India. 

In  the  Alps,  forest  pasture  lasts  only  for  ten  or  twelve  weeks, 
and  sheep-grazing  on  the  high  forest  pastures  of  the  Himalayas 
is  of  a  similar  nature,  these  pastures  not  being  burned.  The 
winter  pastures  in  the  N.-W.  Himalayas,  in  forests  of  Finns 
longifolia,  Roxb.,  are  generally  burned,  both  in  order  to  destroy 
the  dead  needles,  and  to  produce  a  fresh  crop  of  grass.  Forests 
so  treated  must  eventually  disapjiear,  but  the  magnificent  re- 
production of  Piniis  cxcclsa,  Wall.,  in  the  middle  altitudes  of  the 
Himalayas  between  6,000  and  8,000  feet,  since  fire  protection 
has  been  introduced  into  the  forests,  is  most  remarkable. 

In  wet  weather,  forest  grazing  must  be  stopped,  or  carried 
on  in  old  woods  only.  The  usual  daily  grazing  should  com- 
mence only  after  the  sun  has  dried  the  dew,  and  night-grazing 
is  not  generally  allowable.  If  cattle  are  to  be  driven  through 
young  growth,  this  should  be  in  the  afternoon,  after  they  have 
already  had  a  good  meal. 

d.  Species  of  Grazing  Animals. 

Goats,  horses,  and  camels  must  not  be  allowed  to  browse  in 
valuable  forests  ;  their  fodder  should  be  cut  and  brought 
to  them.  The  French  laws  exclude  sheep  as  well  as  goats 
from  all  forests  managed  by  the  State  Forest  Department, 
but  sheep  may  be  admitted  to  graze  in  forests  in  certain 
localities  under  special  sanction.  Elephants  may  be  admitted 
into  forests  with  their  keeper,  and  their  fodder  cut  and  brought 
in  by  them.  A  list  of  climbers  and  inferior  forest  trees  and 
shrubs  suitable  for  the  fodder  of  goats,  camels,  elephants  and 
buffaloes  should  be  drawn  up  and  circulated  amongst  all 
keepers  of  these  animals  who  obtain  fodder  from  a  forest, 
and  the  fodder,  as  far  as  it  consists  of  woody  plants,  should 
be  restricted  to  these  species. 

As  regards  other  grazing  animals,  the  number  to  be  admitted 
into  forests  must  be  carefully  controlled.  This  number  will 
be  determined  by  considering  the  amount  of  their  require- 
ments and  the  available  quantity  and  quality  of  the  herbage 


48  PROJECTION   AGAINST    MAN. 

in  the  forest.  Wherever  tender  grasses  are  availahle,  these 
are  exclusively  grazed  on. 

No  diseased  or  sick  cattle  should  be  admitted,  and  from  one- 
tenth  to  one-fifteenth  of  the  animals  should  be  provided  with 
bells,  those  inclined  to  wander  from  the  herd  being  chosen. 

The  animals  should  be  driven  into  the  forest  only  in  flocks 
or  herds  under  the  care  of  trustworthy  herdsmen,  who  must 
see  that  they  do  not  crowd  together,  nor  stray  too  far  apart. 
A  few  horses  may  be  attached  to  a  herd  of  cattle,  but  cattle 
and  sheep  should  never  be  kept  together  to  graze.  The 
herds  must  not  be  too  great,  not  above  100  to  150  head.  All 
crowding  and  fast  driving,  and  especially  driving  cattle  with 
dogs  through  young  growth,  must  be  forbidden. 

On  slopes  grazing  animals  are  driven  straiglit  up  from 
below,  and  very  slowly,  in  order,  as  much  as  possible,  to  avoid 
damage  by  their  tread. 

Shady  places  in  old  woods  without  undergrowth  should  be 
selected  for  rest  in  the  middle  of  the  day,  and  must  be  near 
water  for  the  animals  to  drink. 

f.  Herdsmm. 

Well-reputed,  trustworthy  people  must  be  selected  as  herds- 
men, and  the  owners  of  the  cattle  held  responsible  for  damage 
or  breach  of  regulations,  any  failing  in  this  respect  being  at 
once  reported  and  seriously  dealt  with. 

The  forest  manager  should  secure  for  himself  a  certain 
influence  in  the  appointment  of  the  herdsmen,  and  endeavour 
to  get  them  to  take  interest  in  the  welfare  of  the  forest,  by 
rewards  for  good  behaviour,  and  discouragement  if  they  are 
careless.  If  the  herdsman  chooses  the  pit)per  moment,  when 
the  beasts  show  an  inclination  to  attack  woody  plants,  to  drive 
them  on  to  another  pasture,  and  when  to  graze  in  3'oung 
woods,  and  selects  old  woods  in  wet  weather — in  fact,  if  he  has 
the  necessary  power  of  observation  and  will  use  it  for  the 
benefit  of  the  forest,  the  damage  done  by  grazing  may  become 
quite  inconsiderable. 

(13)  Gccse,  etc. 

As  regards  domestic  birds  ;  geese,  fowls  and  pigeons  may 
damage  a  forest,  the  former  spoiling  the  pasturage,  and  the 


FOREST   LITTER.  49 

latter  devouring  forest  seeds ;  but  certain  blanks  may  be 
found  suitable  for  geese,  and  the  damage  done  by  fowls  and 
pigeons  is  inconsiderable. 

7.  Forest  Litter* 

As  the  removal  of  litter  consisting  either  of  the  soil-covering 
of  dead  leaves,  needles,  humus,  moss,  etc.,  or  of  branches  of 
forest  trees  in  full  foliage,  is  the  most  hurtful  form  of  utilisa- 
tion of  minor  forest  produce,  its  permission  must  be  looked 
upon  as  altogether  exceptional,  and  only  to  be  granted  under 
most  pressing  necessity  (scarcity  of  straw,  etc.).    ' 

The  then  requisite  protective  measures  are : — 

Limitation  of  the  quantity  of  litter  to  be  removed  to  what 
is  absolutely  required  by  local  farmers  and  peasants.  Not  a 
word  should  be  heard  in  favour  of  selling  the  litter  to  others. 

If  the  rides,  roads,  ditches,  places  from  which  the  wind  would 
inevitably  blow  away  the  litter,  and  hollow  places  where  it 
becomes  heaped-up  unnecessarily  deep  do  not  suffice  for  the 
requisite  supply  of  litter,  then  felling-areas  with  high  herbage 
should  be  opened,  but  growing  woods  only  as  a  last  resort. 

Only  places  with  fertile,  deep  and  fresh  soil  can  bear  a  limited 
deprivation  of  litter.  On  poor,  shallow,  easily  dried,  hot  soils 
and  on  sunny  aspects,  the  collection  of  litter  must  be  uncon- 
ditionally refused.  So  also  in  woods  that  are  insufficiently 
stocked,  or  in  badly  growing  woods,  of  quality  under  0'7. 

Woods  which  have  not  yet  attained  their  maximum  height- 
growth  must  be  closed  against  the  removal  of  litter.  The 
necessary  close-time  depends  on  the  species,  the  locality,  and 
the  length  of  rotation  (r) ;  it  should  be  at  least  ^  r  for  High 
Forest  and  Coppice-with-Standards,  ^  r  for  Coppice,  but  for 
exacting  species,  such  as  the  beech,  we  must  wait  up  to  ^  r 
even  in  high  forest. 

The  repetition  of  the  utilisation  of  litter  is  allowable  only 
after  a  certain  close-time,  which  varies  from  5  to  10  years 
according  to  species  of  wood,  quality  of  locality,  rate  of 
growth,  etc. 

•  For  an  account  of  the  value  of  humus  in  the  soil  of  a  forest,  see  Vol.  II., 
3rd  edition,  p.  41,  et  tteq.,  and  Vol.  V.,  part  II.,  chap.  VII. 

F.P.  B 


50  PKOTECTION    AGAINST    MAN. 

Removal  of  leaves  should  not  be  permitted  two  years  before 
or  after  a  thinning,  and  in  the  case  of  natural  regeneration 
there  must  be  a  close-time  for  litter  4 — 8  years  before  and 
after  a  seeding-felling.  This,  however,  implies  such  a  state  of 
decomposition  of  the  soil-covering,  that  seedlings  can  strike 
their  tap-roots  into  the  mineral  soil.  Wherever  deep  layers 
of  undecomposed  humus  prevent  this,  they  must  be  removed 
so  as  to  expose  the  mineral  soil. 

The  most  suitable  time  in  Europe  for  removing  litter  is 
on  sunny  dry  days  in  September  and  October,  shortly  before 
the  fall  of  the  leaf.  This  rule  will  require  modifying  where, 
as  in  hot  cbuntries,  some  of  the  trees  lose  their  leaves  in 
the  spring. 

Iron  rakes  must  not  be  used  for  collecting  litter,  as  they  go 
in  too  deep  and  may  injure  the  roots  of  the  trees  ;  brooms  also 
remove  too  much  litter.  Only  the  uppermost  undecomposed 
layer  of  litter  should  be  removed.  Cutting  and  removal  of 
sods  of  grass  with  the  roots  must  be  forbidden. 

As  regards  moss,  species  oillypnum  sliould  be  removed  only 
in  strips  during  the  spring,  so  that  the  regeneration  of  the 
moss  on  the  bare  places  may  be  facilitated  from  the  strips  left 
untouched ;  this  happens,  when  the  soil  is  fertile  and  moist, 
in  about  six  years.  Then  the  old  strips  of  •  moss  may  be 
removed,  and  another  six  years  left  for  the  bare  places  to 
recover,  and  so  on.  Species  of  Pohjtrlchum  and  Sphacjnum, 
which  generally  grow  in  patches  on  wet  soil,  cause  swamps 
and  are  hurtful  rather  than  useful,  and  can  therefore  always 
be  removed. 

Branch  lop})ings  for  litter,  best  from  silver-fir,  should  be 
conceded  only  from  felled  trees  or  from  those  just  about  to  be 
felled.  Sometimes  it  may  be  useful  to  allow  grass,  heather, 
broom,  bracken,  etc.,  to  be  cut  in  young  plantations,  for  use 
as  litter.  The  kind  of  implement  to  be  used  will  depend  on 
circumstances. 

Dtiring  removal  of  the  litter,  the  forest  must  be  carefully 
watched,  and  wherever  annual  permission  for  litter  is  given, 
a  scheme  should  be  drawn  up,  allotting  the  open  areas  for 
successive  years. 

By   careful    economy    in    the   preservation   and  use  of  all 


DEAD    BRANCH- WOOD.  51 

manures,  and  by  the  use  of  straw  and  provision  of  fodder- 
crops  for  stock,  the  demand  for  forest  litter  may  be  reduced ; 
it  is  the  duty  of  the  State  to  impart  pubhc  instruction  in  this 
respect,  and  as  to  the  extreme  impoverishment  of  forest  soil  by 
the  constant  removal  of  litter.  The  worst  possible  instances 
of  damage  to  the  soil  by  the  removal  of  litter  are  exhibited  by 
the  State  forests  near  Nuremberg  in  Bavaria,  where  even 
Scots  pine,  in  some  parts  of  the  forest,  can  now  grow  only 
as  a  dwarfed  scrubl)y  tree  almost  useless  except  for  fuel. 
Litter  from  coppice-with-standards  in  Kent,  Sussex  and 
Hampshire  is  regularly  used  for  manuring  hop-lields,  to  the 
impoverishment  of  the  soil  of  those  woodlands. 

8.  Dead  Branch-icood. 

Wherever  the  removal  of  dead  branch-wood  is  not  a  right 
of  usage,  but  is  permitted  under  certain  conditions  by  the 
forest  manager,  the  following  rules  apply  : — 

Written  or  printed  permits  for  the  removal  of  the  dead  wood 
must  be  held  by  each  person  so  engaged  in  order  to  prevent 
the  concession  from  becoming  a  right,  and  generally,  people 
too  poor  to  purchase  fuel  should  be  favoured  in  this  respect, 
but  they  should  not  be  allowed  to  sell  the  wood. 

Very  poor  or  exposed  localities  in  the  forest  should  be 
excluded  from  the  use  of  this  concession,  as  the  dead  branches 
increase  the  humus  of  the  soil. 

As  a  rule,  no  tools  should  l)e  used,  but  where  removal  of 
dead  branches  from  standing  trees  is  allowed,  they  should  be 
sawn  off  close  to  the  stem. 

In  order  to  facilitate  control,  the  removal  of  dead  wood 
should  be  allowed  only  on  certain  days,  and  not  between 
sunset  and  sunrise,  and  the  forest  carefully  watched  on  those 
days. 

Wherever  game  is  of  importance,  the  privilege  must  bg 
suspended  during  the  breeding  season. 

It  may  be  necessary  to  prescribe  the  removal  by  certain 
roads  in  order  to  facilitate  control. 

The  removal  of  fallen  dead  wood  is  not  so  harmless  as  many 
people  think,  as  a  considerable  amount  of  humus  is  formed 

E  2 


52  protf:ction  against  man. 

from  it.  Thus  sapwood,  of  wliieli  young  branches  are  chiefly 
composed,  contains  far  more  potash  than  heartwood. 

In  the  Crown  forests  of  Hesse  the  privilege  of  collecting 
dead  wood  gratis  is  subject  to  the  following  rules : — 

All  dry  fallen  wood,  which  in  tlie  opinion  of  the  forest 
manager  is  unsuitable  for  sale,  may  be  taken.  Also  dead 
branches,  which  can  be  broken  off  by  hand  by  one  person 
without  climl)ing  the  trees,  provided  it  be  not  over  6  cm, 
(2|  inches)  in  diameter.  Only  poor  people  provided  with 
formal  permits  are  admitted  between  sunrise  and  sunset  to 
this  privilege.  All  tools  are  excluded,  and  no  sale  of  the  wood 
allowed.  Transport  is  by  head-loads,  or  in  hand-sledges. 
The  privilege  is  stopped  during  May  and  June. 

In  North-West  Indian  State-forests,  the  privilege  of 
removal  of  dead  fuel  is  frequently  leased  annually ;  it  is  also 
granted  free  to  villages  paying  grazing  dues,  and  to  travellers 
on  high  roads  passing  through  the  forests. 

9.  Ut'))ior<il  of  Stones,  Gravel,  Sand,  etc. 

The  following  rules  should  be  enforced  : — 

All  quarries,  sand,  clay  and  gravel  pits  must  be  properly 
demarcated,  and  the  boundaries  strongly  walled  or  fenced  to 
prevent  accidents.  Proper  precautions  must  be  taken  that 
neither  roads,  nor  streams,  nor  the  forest  outside  the  quarry 
are  imperilled  by  quarrying. 

Jn  agreements  made  with  lessees  of  stone-quarries,  etc.,  they 
may  have  to  pay  for  repairs  to  forest  roads  leading  from  the 
quarry ;  they  should  also  be  held  responsible  for  any  damage 
done  by  their  employees.  In  French  State-forests,  wliere 
coal-mines  are  worked  below  the  forests  and  subsidences 
occur,  the  coal  companies  have  either  to  restore  the  ground 
to  its  original  level  and  replant  it,  or  to  dig  out  fish- tanks, 
which  are  valuable  in  Fi-ance. 

Stones  lying  about  on  the  ground  should  be  collected  only 
where  their  removal  is  not  prejudicial  to  the  forest,  and  when 
removed,  the  ground  where  they  were  lying  should  be  levelled. 
Eemoval  of  loose  stones  should  not  generally  be  allowed  on 
the  sites  of  fellings,  especially  on  loose  sandy  or  calcareous  soils 


GAME    AND    FISHERIES.  58 

that  dry  up  easil.y  ;  stones  retain  moisture  in  the  soil.  Phices 
must  be  assigned  where  the  stones  may  be  stored  and  roads 
designated  for  their  removal. 

Pits  of  sand,  clay  and  gravel,  that  have  been  abandoned, 
should  be  levelled  or  sloped-off  to  prevent  accidents,  and 
if  possible  planted.  This  rule  is  specially  applicable  to 
experimental  pits  abandoned  as  not  sufficiently  profitable. 

10.  Collection  of  otlicr  Items  of  Minor  Produce. 

Collecting  berries,  such  as  bilberries,  wild  strawberries, 
raspberries,  etc. ;  edible  fungi ;  empty  cones  lying  on  the 
ground ;  grass-seeds ;  medicinal  herbs  or  fruits,  and  other 
such  produce,  the  collection  of  which  is  not  worth  the  trouble 
of  the  forest  owner,  must  be  so  regulated  that  only  persons 
provided  with  formally  written  or  printed  permits  should  be 
admitted,  and  the  period  of  collection  fixed.  In  hot  countries, 
some  of  those  products  attain  a  much  greater  importance  than 
in  temperate  regions,  and  certain  special  rules  may  be  neces- 
sary, as  in  the  collection  of  wild  honey  and  wax  in  India,  where 
care  must  be  taken  to  prevent  the  collectors  from  firing  the 
forest,  so  that  it  may  be  necessary  to  prohibit  the  collection 
altogether  except  during  seasons  when  the  grass  or  other  soil- 
covering  in  the  forest  will  not  burn. 

11.  Game  and  Fisheries. 

Leases  in  forests  of  the  right  to  hunt  or  shoot  game,  and  of 
fisheries,  frequently  produce  considerable  annual  revenues,  but 
whilst  little  or  no  damage  is  done  by  pheasants  and  other 
birds,  deer  and  ground-game  (hares  and  rabbits)  may  do  a 
great  amount  of  harm  to  a  forest.  The  measures  to  protect 
forests  against  these  animals  will  be  given  further  on. 

The  protection  of  game  and  fisheries  is  dealt  with  in  special 
treatises,  and  would  take  up  too  much  space  in  the  present 
book.  In  most  civilised  countries  there  are  special  laws 
relating  to  game,  and  these  should  be  so  framed  as  not 
only  to  prevent  wholesale  destruction  of  useful  wild  animals, 
especially   during    their  breeding  season,   but  also    to  atl'ord 


54  PROTECTION    AGAINST    MAN. 

compensation  to  owners  or  tenants  of  land  bordering;  on  a 
forest,  for  damage  done  to  their  crops  by  anj^  excessive  head  of 
game  which  may  be  preserved  in  the  forest.  They  should  also 
fix  a  minimum  limit  to  the  area  on  which  a  man  may  claim  the 
exclusive  right  of  shooting  on  his  own  land ;  this  is  especially 
required  in  countries  where  landed  property  is  much  subdivided. 
Such  a  limit  is  25  hectares  (62^  acres)  in  Germany,  but  owners 
of  such  small  areas  may  combine  with  others  to  form  shooting 
syndicates.  In  French  State-forests,  sporting  leases  generally 
run  for  nine  years,  the  lessee  having  to  pay  for  any  wire-fences 
that  may  be  required  to  protect  the  young  growth. 

Fisheries  are  also  regulated  by  laws.  In  France,  since  1897, 
the  preservation  and  control  of  fisheries  in  all  State  non-tidal 
waters,  have  been  placed  under  the  State  Forest  Department, 
which  is  styled  ''Administration  des  Eanx  et  Foi-cts." 

Their  plan  of  operations  over  342  miles  of  canals  and 
canalised  rivers,  and  210  miles  of  other  rivers  that  belong  to 
the  State,  is  : — 

1.  To  form  reserved  waters  where  fish  can  freely  propa- 
gate. On  other  streams,  private  fishing  rights  prevent  State 
interference. 

2.  Eewards  are  offered  to  fishery  guards  and  to  forest 
guards  for  protecting  natural  breeding-places  of  fish  and  for 
establishing  new  ones,  for  killing  otters  and  other  fish-enemies, 
for  protecting  streams  against  netting  by  driving  stakes  into 
river-beds. 

3.  Fish-ladders  are  erected. 

4.  Live  fish  are  bred  in  special  piscicultural  establishments 
and  are  placed  in  State  streams,  lakes,  and  grounds.  They 
are  also  distributed  to  private  fishery  owners. 

5.  Crayfish  have  died  out  to  a  large  extent  in  France  from 
disease,  and  fresh  crayfish  are  imported  and  placed  in  the 
rivers. 

6.  Pisciculture  is  taught  at  the  National  Forest  School,  at 
Nancy,  where  a  special  piscicultural  laboratory  and  breeding 
establishment  is  maintained,  the  latter  in  the  adjoining  forest 
of  Haye. 


55 


CHAPTER   III. 

PBOTECTION   OF   THE  FOREST  AGAINST  OFFENCES. 

1.  General  Account  of  the  Subject. 

The  theory  of  forest  legislation  and  the  law  of  forest  police 
is  dealt  with  under  Forest  Law.* 

There  are,  of  course,  a  number  of  acts  in  a  forest  con- 
stituting an  infringement  of  the  rights  of  the  owner,  which  may 
be  remediable  only  by  a  eiril  court : — either  by  a  suit  for  an 
injunction  to  the  offender  not  to  repeat  his  act,  or  for  damages. 
Of  such  cases  it  is  not  necessary  to  speak  in  detail ;  but  a 
word  may  be  said  about  "  trespass."  Ordinarily  an  entry  on 
a  man's  property  which  is  not  lawfully  warrantable  gives  rise 
to  an  action  for  damages  ;  Init  under  the  English  law  (and  so 
in  India)  trespass  cannot  he  j^i'osecuted  criminalhj,  unless  there 
is  proof  that  the  entry  was  with  intention  to  do  "mischief" 
or  commit  a  legal  offence  of  some  kind.  When,  therefore,  in 
forests,  it  is  desirable  (owing  to  the  special  circumstances)  to 
make  penal  the  mere  act  of  climbing  a  fence  and  aimlessly 
wandering  (oft'  regular  paths)  in  a  compartment,  or  a  young 
plantation,  it  can  be  done  only  by  an  express  enactment  of  a 
suitable  prohibition  and  (light)  penalty. 

2.  Definition  oj  a  Forest  0§'ence. 

Under  the  term  "forest  offence"  is  here  included  any  act 
done  in  a  forest  which  is  punishable  under  an  existing  forest  or 
other  law.  Offences  which  affect  or  threaten  forests  (or  the 
produce  of  them  when  converted  and  stored,  or  in  transit)  or 
which  interfere  with   control,  are  naturally  sometimes  of  a 

•  Reference  may  be  made  to  "  Forest  Law,"  by  B.  H.  Baden-Powell,  CLE., 
London  (Bradbury,  Agnew,  &  Co,  Ld.),  1893,  wh,ich  also  refers  to  the  principal 
woiks  on  the  subject.. 


66  PROTECTION    AfiAIXST    MAX. 

kind  which  might  occur  in  respect  of  any  property,  and 
sometimes  of  a  special  character :  i.e.  the}'  happen  only 
in  forests  and  are  not  attempted  elsewhere ;  or  else  are 
exceptionally  dangerous  or  injurious  when  done  in  a  forest 
(or  with  regard  to  forest  property  generally).  Hence  in 
most  sj'stems  of  law,  "offences"  are  partly  punishable  under 
the  provisions  of  a  forest  law,  and  partly  under  the  ordinary 
"Penal  Code"  or  the  statute  and  common  law  of  the 
country. 

In  India,  for  example,  such  offences  will  sometimes  come 
under  the  Forest  Acts  ;  sometimes  under  the  Penal  Code  ; 
sometimes  under  either.  And  it  is  a  matter  for  the  law 
manuals  to  tell  us  when  one  law  or  the  other  should  be  had 
recourse  to.  In  the  British  Isles  there  is  no  special  forest 
law ;  accordingly  all  "  offences  "  that  are  punishable  (as 
distinguished  from  acts  which  give  rise  to  a  claim  for  damages) 
are  so  under  the  ordinary  (Criminal)  Common  and  Statute 
Law. 

3.  Classification  of  Forest  Offences. 

Forest  offences  may,  therefore,  be  classified  as  follows : — 
(a)  Damage  : 

Unintentional. 
Wilful. 
{h)  Misappropriation  : 
Simple. 

Accompanied  by  damage. 
{c)  Contraventions  of  forest  police. 
The  subjects  of  forest  offences  are  sometimes  the  forest  soil, 
or  its  covering ;  the  stock  of  wood  or  minor  produce,  whether 
standing   or  converted;  houses,  roads  and  other  works  and 
appliances  used  in  forest  business. 

a.  Damage. 

Unintentional  damacje  occurs  in  a  variety  of  ways,  as  for 
instance: — damage  to  standing  trees  through  clumsy  felling 
of  other  trees,  to  young  growth  during  fellings  or  removal  of 
material ;  cutting  up  valuable  timber  into  firewood  in  ignor- 
ance of   its  value ;  cutting    seedlings    during   grass-cutting ; 


FOREST    OFFENCES.  57 

driving  carts  over  boundary  marks,  through  ditches,  down 
embankments,  etc.  The  number  of  cases  which  may  occur  is 
80  great,  that  to  draw  up  a  complete  Hst  here  is  impossible. 
In  many  cases  no  legal  offence  is  connnitted  which  is  punish- 
able criminally ;  but  the  doer  of  the  damage  is  liable  to  make 
reparation. 

In  the  case  of  wilful  damar/c,  the  motives  may  be  wantonness, 
revenge,  selfishness,  even  superstition.* 

Damage  of  this  kind  includes  : — peeling  the  bark  from 
standing  trees,  girdling,  cutting-off  leading  shoots,  lopping 
branches  or  exposed  i-oots ;  lopping  branches  from  trees  yielding 
mast,  or  from  cone-bearing  trees  in  order  to  facilitate  the 
removal  of  their  fruit ;  wilful  damage  to  boundary  marks, 
fences,  forest  nurseries,  or  other  forest  appurtenances. 

J?.  JUisa/)/)ropri(//ion . 

Under  this  heading  is  understood  illegal  appropriation  of 
forest  property  still  belonging  to  the  forest  owner. 

In  most  systems  of  law  "theft"  and  "  larceny  "  refer  to 
"personal"  or  "moveable"  property:  such  as  a  watch,  fire- 
wood in  a  stack,  a  log,  or  a  beam  ;  and  there  is  (or  may  be)  a 
difficulty  about  prosecuting  cases  of  lopping,  or  the  offence  of 
cutting  a  standing  or  growing  tree,  bush,  or  sapling ;  gener- 
ally, therefore,  the  forest  law  (if  there  is  one)  will  specially 
provide  for  these  cases,  and  will  leave  "  theft "  of  forest  pro- 
duce (stored),  cut  timber,  etc.,  to  the  ordinary  law.t  Where 
there  is  no  special  forest  law,  the  cutting  of  standing  trees 
would  at  any  rate  constitute  "  wilful  damage  "  or  "mischief." 

Simjyle  misappropriation  (in  the  general  sense  of  the  term) 
is  unaccompanied  by  any  damage  to  the  forest,  so  that  no  loss 
of  increment,  no  impoverishment  of  the  soil,  results  from  the 
offence,  but   merely  the  loss  of  the  property  illegally  taken 

•  About  thirty  years  ago  a  deodar  forest  in  Jaunsar,  in  the  N.-W.  Himalayas, 
was  deliberately  burned  to  propitiate  the  goddess  of  small-pox. 

t  In  India,  a  technical  distinction  is  drawn  between  "theft  "and  misappro- 
priation," for  which  see  "  Forest  Law"  (pp.  118,  420),  It  is  provided,  however, 
in  the  Indian  law,  that  though  "theft"  can  only  be  of  '-moveable"  property, — 
and  a  standing  tree  is  not  such, — still  the  act  of  cutting  and  severing  the  free 
from  the  soil  may  make  the  object  moveable  and  also  effect  the  moving  with 
dishonest  intention  that  is  necessary  to  constitute  ■'  llitft.  ' 


58  PROTECTION    AGAINST    MAN. 

away.  In  this  is  included  the  illegal  removal  of  dead  standing 
trees  (provided  no  damage  is  thus  done  to  living  trees) ;  of 
dead  branches  or  windfalls  ;  of  fruits  not  required  for  natural 
reproduction ;  of  grass  from  rides,  or  roads ;  of  stones  lying 
on  the  ground,  berries,  edible  fungi,  etc. 

ISrisappropnatiun  accompanied  by  damaf/e  is  committed  when 
the  forest  owner,  in  addition  to  the  loss  of  the  articles 
abstracted,  suffers  physical  damage  to  his  property,  which 
may  differ  greatly  in  degree  according  to  circumstances 
(species,  age  of  wood,  system  of  management,  density  of 
growth,  locality,  etc.). 

To  offences  of  this  class  belong,  as  regards  principal  pro- 
duce : — cutting  and  removal  of  standing  timber,  or  parts  of 
standing  trees,  involving  loss  of  increment  and  irregularity  of 
management,  or  introducing  decay  into  the  wood  ;  removal  of 
mother-trees  in  regeneration-fellings,  or  of  standards  in  stored 
coppice,  resulting  in  delay  in  the  i-eproductiou  of  the  wood, 
deprivation  of  shelter  against  atmospheric  influences  for  the 
young  growth,  exposure  of  the  soil,  etc.  Some  of  the  most 
harmful  of  these  offences  are  digging  up  green  stools  from 
coppice,  and  removal  of  young  plants  from  plantations,  as 
thus  the  care  taken  to  restock  a  wood  is  frustrated.  Another 
very  harmful  offence  in  Germany  is  the  breaking  off  of  the 
leaders  and  side-shoots  of  young  pines  by  children  for  sale  to 
apothecaries,  who  grind  them  up  and  export  them,  chiefly  to 
America,  as  medicine,  under  the  name  Turioiies  pini. 

As  regards  minor  produce : — peeling  bark,  tapping  for  tur- 
pentine or  gum,  lopping  branches  for  fodder,  grazing,  raking- 
up  litter,  cutting  sods,  and  appropriation  of  the  resulting 
produce,  are  common  offences.  When  tall  herbage  is  pulled 
up  round  seedling  plants,  or  excessive  layers  of  humus  are 
removed  from  felling  areas,  the  owner  of  the  forest  may 
actually  profit  by  the  offence.  Such  nominal  offences  may 
be  prevented  by  permits  to  remove  noxious  material. 

In  many  of  these  cases,  as  for  instance  in  the  removal  of 
litter,  the  damage  done  to  the  forest  far  exceeds  the  value  of 
the  material  al)stracted. 


FOREST    OFFENCES.  59 

c.  Contrareiition  of  Forest  Police  Rf'fj illations. 

The  offences  comprised  under  the  al)Ove  heading  are  infrac- 
tions of  poHce  regulations  made  for  the  pubHc  welfare,  or  in 
the  interests  of  forest  conservanc}'.  No  damage  need  result 
from  such  ofi'euces,  as  for  instance  from  kindling  a  fire  in  a 
forest  which  may  become  extinguished  without  causing  a 
forest  fire,  although  there  is  an  imminent  probability  that 
such  a  calamity  will  happen,  and  this  probability  necessitates 
the  stringent  prohibition  of  such  an  act.  Offences  of  this 
nature  may  be  placed  in  the  following  groups  : — 

(i)  Offences  (ujainst  forest  control. — Examples  :  removal  of 
wood  without  permission,  at  a  forbidden  time,  or  by  a  closed 
road ;  collection  of  dead  fallen  wood  without  a  permit,  on 
forbidden  days,  or  with  prohibited  tools,  etc. 

(ii)  Offences  endangeriny  the  forest. — Examples  :  lighting  a 
fire ;  leaving  unextinguished  a  fire  lighted  with  permission  of 
the  forest  manager  ;  carelessness  in  burning  charcoal  or  lime ; 
smoking  pipes  without  covers  ;  going  into  a  forest  with 
torches,  etc, 

(iii)  Acts  ineparatory  to  a  forest  offence,  which  are  conse- 
quently prohibited  : — Examples  :  trespass  by  climbing  over 
fences,  carrying  axes  or  saws  in  a  forest  without  permission, 
injury  to  notices,  etc.  Forest  trespass  (in  closed  places,  off 
regular  paths,  etc.)  where  this  is  made  penal  by  law. 

Many  forest  offences  comprise  damage  or  misappropriation, 
as  well  as  contravention  of  regulations;  as  for  instance  injury 
to  growing  trees  by  transport  on  a  prohibited  road,  kindling  a 
fire  in  a  forest  with  misappropriated  wood,  etc. 

Such  complications  may  involve  several  heads  of  charge  in 
the  prosecution  case,  or  call  for  severer  punishment  than 
offences  of  a  simpler  nature. 

4.  Protective  Measures. 

Protective  measures  against  forest  offences  may  be  either 
direct  or  indirect.  The  latter  chiefly  involve  removal  of  the 
cause  of  offences,  and  the  former  are  directed  against  the 
offence  itself;  it  is,  however,  difficult  to  draw  the  line  between 
them. 


60  I'KOIKCTION    AGAINST    MAN. 

Unfortunately,  forest  offences  are  always  considered  hy 
country  people  less  culpable  than  those  against  the  penal  code, 
as  many  German  proverbs  show.  This  results  from  the  former 
communal  possession  of  many  forests,  and  the  small  value  of 
forest  produce  in  earlier  times.  Even  now,  the  appropriation 
of  Christmas  trees,  birches  for  Whitsuntide  and  sallow  branches 
in  bloom  for  Palm  Sunday,  are  frequently  considered  justifi- 
able. The  forester  should  not  be  too  exacting  regarding  certain 
mnocent  practices  ingrained  in  the  popular  mind,  and  he 
should  endeavour  to  become  acquainted  with  all  local  customs 
which  prevail  near  his  forests. 

The  following  are  the  protective  measures  against  forest 
offences  : — 


a.  RcmovaJ  of  Causes  of  Offrnce. 

Want  of  occupation  and  consequent  poverty. often  leads  to 
an  increase  of  forest  offences.  As  a  population  increases, 
without  more  opportunities  for  employment  arising,  and  as 
the  clearance  of  communal  and  private  forests  causes  a  rise 
in  the  price  of  forest  produce,  the  temptation  to  commit 
offences  is  increased.  They  are  also  more  frequent  near 
populous  towns  than  elsewhere,  as  the  trade  in  stolen  forest 
produce  is  thus  facilitated.  At  Hardwar  in  N.-W.  India,  in 
1882,  unmarked  forest  produce  brought  into  the  town  Mas 
regularly  priced  lower  than  properly  certificated  produce,  as 
the  former  was  suspected  of  having  been  misappropriated  and 
might  get  the  purchaser  into  trouble.  Insufficient  education, 
careless  watching  of  a  forest,  bad  forest  legislation,  and  a 
feeble  execution  of  justice  on  the  part  of  magistrates,  ma}'  all 
combine  to  increase  forest  offences. 

The  subject  of  Forest  Policy  comprises  a  study  of  the  above 
factors,  and  only  the  energetic  action  of  the  State  can  ensure 
thorough  protection  to  forests  against  forest  offences.  Under 
Forest  Protection,  we  can  rely  only  on  means  within  the  power 
of  the  private  forest  owner,  which  are  as  follows  : — 

(i)  Careful  utilisation  of  all  forest  products,  so  that  all  local 
wants  may  as  far  as  possible  be  supplied.  Frequent  sales  of 
l)roduce,  and  in  small  lots,  and  credit  given  for  a  certain  part 


FOREST    OFFENCES.  61 

of  the  purchase-money  until  the  purchaser  can  begin  to  reahse 
the  vakie  of  his  purchase,  are  useful  measures. 

(ii)  Provision  should  also  be  made  for  the  sale,  by  printed 
or  written  permit,  of  kinds  of  principal  forest  produce  which 
frequently  form  the  object  of  misappropriation,  such  as  hop- 
poles,  props  for  fruit-trees,  cart-axles,  wood  for  ploughs,  pea- 
sticks,  thorny  bushes  or  stakes  for  fences,  bast  for  rope- 
making,  Christmas  trees,  faggots,  stumps  and  roots  of  felled 
trees,  etc.* 

(iii)  Permits,  if  necessary  without  payment,  to  remove 
certain  minor  forest  produce  as  far  as  is  consistent  with  the 
safety  of  the  forest,  should  also  be  obtainable  throughout  the 
year.  For  instance,  to  cut  grass ;  for  dead  fallen  fuel  ;  to 
collect  berries,  edible  fungi,  cones ;  to  utilise  some  kinds 
of  litter  the  removal  of  which  is  not  harmful ;  in  certain 
cases  for  the  temporary  cultivation  of  crops.  Tall  coarse 
grasses  may  frequently  be  removed  to  the  advantage  of  a 
forest,  and  thus  may  be  secured  less  danger  from  frost  and 
fire,  more  heat  and  moisture  in  the  soil,  and  loosening  of  the 
surface,  all  of  which  are  important  for  plantations.  In  the 
case  of  temporary  cultivation,  potatoes  are  to  be  preferred  to 
cereal  crops,  as  they  impoverish  the  soil  less. 

(iv)  Supplying  work  in  the  forest  during  winter  or  at 
other  seasons  when  employment  is  scarce.  When  a  village 
near  a  State  forest  has  been  burned,  building  and  thatching 
material  may  be  supplied  free,  or,  at  a  low  price,  in  order  to 
prevent  dealers  in  such  material  from  charging  excessive 
prices  to  the  distressed  villagers.  Roads,  drainage,  ditch- 
ing and  removal  of  slumps,  will  furnish  employment,  in 
addition  to  the  ordinary  felling  and  planting  work  in  a  forest. 

(v)  In  the  case  of  communal  forests  we  have  moreover  to 
secure  economy  in  the  use  of  firewood  by  introducing  the  use  of 
improved  stoves,  ovens,  etc.  The  firewood  store-depots  should 
be  centrally  situated,  so  as  to  facilitate  removal  of  the  material 
by  the  householders.  The  wood  should  be  delivered  dry  and 
in  the  smallest  quantities  in  demand. 

•  In  '•  Rev.  des  E.  et  F.,"'  1905,  p.  688,  it  is  stated  that  sales  of  small  felling 
areas  of  coppice  in  Algeria  have  resulted  in  a  considerable  reduction  of  offences. 
The  people  living  near  the  forests  formerly  gained  their  livelihood  partly  by 
illicit  fellings  or  thefts  of  forest  produce. 


62  PROTECTION    AGAINST    MAN. 

(vi)  Iinproveiiient  of  agricultural  methods,  so  that  agriculture 
may  depend  as  little  as  possible  on  the  forest.  Common-land 
should  be  used  to  the  best  advantage ;  technical  instruction 
in  agriculture  should  be  afforded,  etc. 

(vii)  Much  may  be  done  by  the  exercise  of  tact  and  kind- 
ness in  the  administration  of  a  forest,  to  prevent  the  ignorant 
peasantry  from  feeling  the  forest  to  be  a  hostile  institution  in 
their  neighbourhood.  This  need  not  impair  the  effectiveness 
with  which  important  rules  are  enforced  and  the  safety  of 
the  forest  ensured.  It  is  possible  so  to  act  as  to  make  the 
people  not  dislike  the  control,  by  using  discretion  in  enforcing 
particular  prohibitions.  Ignorant  peasantry  will  always  dis- 
like forest  conservancy  ;  but  they  need  not  feel  it  a  grievance : 
there  is  an  irritating  kind  of  exactness  which  tends  to  pro- 
voke a  spirit  of  malice  and  a  desire  to  injure  the  forest ; 
whereas,  a  judicious  management  will  in  time  disseminate  the 
idea  that  the  forest  is  after  all  a  benefit,  and  that  the  forester 
is  not  the  enemy  of  the  people.* 


h.  Direct  Dealing  with  Forest  Offences. 

(i)  The  forest  should  be  subdivided  into  beats  of  suitable  size 
and  shape  ior patrolling  and  keeping  watch  against  trespassers, 
or  against  the  causes  or  origin  of  fire ;  in  Germany,  the  area  of 
a  beat  ranges  between  500  and  1,800  acres,  the  latter  in  Wiir- 
temberg,  the  mean  area  being  1,150  acres.  Trustworthy  forest 
guards  should  be  appointed,  who  should  be  allowed  sufficient 
pay  and  houses  well  situated  as  regards  their  beat,  also  allot- 
ments for  a  garden  and  potato-field,  and  pasture  for  one  or  two 
cows  on  forest  rides  and  blanks.  Proper  control  of  the  guards, 
and  promotion  and  reward  of  good  men  must  be  seen  to  by  the 
forest  managers.  Friendly-societies  of  the  guards  should  be 
encouraged. 

(ii)  Wood-cutters  and  contractors  employed  on  work  should 
be  induced  to  participate  in  the  protection  of  the  forest. 

The  forest  should  be  constantly  inspected,  and  all  workmen 

*  In  the  Jaunsar  district  in  India,  the  wages  paid  annually  by  the  Forest 
Department  were  in  1888  sufficient  to  cover  the  rent  paid  to  Government  by 
the  peasants. 


FORKST    OFFENCES.  63 

employed  in  it  supervised.  Proper  rules  regarding  forest  tires 
must  be  duly  made  known  and  strictly  enforced. 

(iii)  All  forest  offences  must  be  promptly  reported,  and  tlie 
ofifenders  prosecuted.  There  are  some  particular  ofiences 
against  which  special  remedies  may  be  adopted.  "Where 
tappings  for  turpentine  have  been  illegally  effected,  they  may 
be  smeared  with  lime-water,  which  stops  the  flow  of  turpen- 
tine. Where  removal  of  litter  is  to  be  feared,  stumps  may  be 
left  somewhat  high  at  the  thinnings,  or  stakes  driven  into  the 
ground  to  impede  progress.  All  stumps  of  stolen  trees  should, 
on  discovery,  be  marked  with  a  special  hammer  to  facilitate 
control. 

(iv)  Wherever  it  is  possible  to  free  forests  from  rights-of- 
common,  this  should  be  done,  as  abuses  almost  always 
accompany  them.  A  comparison  between  open  and  closed 
forest  is  shown  in  Fig.  20. 


Fig.  20. — New  Forest,  1900.     Comparison  between  closed  and  open  forest. 
Kindly  supplied  by  Commissioners  of  Woods  and  Forests. 


64 


CHAPTER  IV. 

PROTECTION    AGAINST    DANGER    FROM    FOREST 
RIGHTS. 

Section  I. — General  View  of  Forests  as  "Estates"  or 
Pieces  of  Property. 

1.   What  is  Property  ? 

A  discussion  cannot  here  be  attempted  of  the  legal  defini- 
tions of  property,  or  the  questions  involved  in  legal  possession, 
and  so  forth,  with  which  the  whole  subject  is  bound  up.  We 
commence  with  the  practical  consideration,  that  in  modern  times 
most  things  that  are  available  for  use  have,  or  are  presumed 
to  have,  an  owner.  In  particular  all  land  (in  countries  where 
there  is  a  civilised  government)  has  come  to  be  recognised  as 
the  "property  "  of  someone  :  even  an  open  moor  or  waste  is 
owned  by  someone.  This  ownership  implies  the  following 
elements : — 

(a)  That  within  certain  limits  or  boundaries, 

{h)  the  "  owner"  has  certain  positive  rights:  which  other 
people  have  not. 

(c)  He  has  also  the  negative  right,  that  other  persons  are 
bound  not  to  interfere  with  his  rights. 

In  either  case  there  is  a  legal  remedy,  which  the  owner  can 
invoke  in  the  case  of  an  infringement  of  his  right. 

{(l)  It  is  possible  that  some  other  persons  (without  actually 
infriufjing  the  owner's  right)  may  have  certain  rights  of  their 
own  which  limit  the  enjoyment  of  the  owner  ;  if  so,  these 
rights  must  be  known  and  certain. 

Where  these  conditions  are  not  yet  legally  existing  there 
cannot  be,  for  any  practical  purposes  of  management  or 
control,  an  estate  or  property. 

Where  the  owner's  right  (a  and  h  above)  is  not  limited  by 
the  existence  of  other  rights  under  {d),  the  lawyers  shortly 


FOREST   RIGHTS.  05 

express  the  sum  of  his  rights  as  oirncr,  by  saying  that  he 
has  the  use  (every  possible  advantage  from  the  estate) ;  the 
abuse  (the  right  to  destroy  and  make  it  a  waste,  unless  some 
express  law  pi-events  him)  ;  the  fruifs,  i.e.  all  produce  and 
accessories  ;  and  lastly,  the  right  to  let,  hire,  alienate,  and 
maintain  any  kind  of  legal  action  necessary  to  defend  his 
property. 

2.   0/  t1ie  Persons  wJio  are  Owners. 

Forest  property  may  belong  to  an  individual  owner,  or  to  a 
partnership  or  body  of  co-owners,  or  to  the  State ;  or  to  what 
is  called  an  artijicial  or  legal  person,  namely,  some  body  of 
men,  or  individual  holding  a  peculiar  position,  or  even  an 
official  trust,  or  some  institution,  which  the  law  regards  as 
if  it  were  one  single  person,  taking  (as  regards  the  property 
owned)  no  thought  of  the  individual  member  or  members 
composing  it. 

The  corporation,  as  a  legal  person  is  called,  is  exemplified 
by  the  "  Crown,"  the  "  rector  of  a  parish,"  a  town  corpora- 
tion, a  college,  charitable  or  other  body,  which  is  by  law,  or 
by  a  Royal  Charter  declared  to  be  corporate.  In  such  cases 
the  law  or  charter  specifies  the  officer  (chairman,  secretary, 
etc.)  who  is  to  represent  the  corporation  :  the  act  of  the  whole 
body  is  signified  by  a  conunon  seal.*  The  individual  members 
of  a  corporation  have  no  interest  in  or  liability  for  the 
property  whatever,  nor  can  they  take  any  action  regarding 
it.  Thus  corporate  property  differs  from  property  where 
the  owner  is  a  company  (not  being  a  corporation),  or  a 
partnership,  or  a  set  of  two  or  more  joint  owners  :  for  all 
these  have  separate  rights  and  individual  interest,  although 
until  partition,  no  one  of  them  alone  can  deal  with  any 
portion  of  the  estate. 

3.  Limitation  of  Owner's  Riylit. 

In  the  short  enumeration  of  the  characteristics  of  property 
it  was  noted  that  sometimes,  though  there  was  an  owner  to 

*  This  has  nothing  to  do  with  the  departniental  official  seal  used  by  a  forest 
department  or  government  secretariat,  etc.  The  "  State"  or  "  the  government" 
as  owner  of  forests  and  so  forth,  is  not  exactly  a  corporation — but  it  is  analogous. 
State  property  is  always  provided  to  be  managed  and  held  by  someone — e.ff.  the 
Secretary  of  State  for  India  in  Council,  in  the  case  of  public  property  in  India, 

P.P.  F 


66  PROTECTION    AOAINST    MAN. 

the  estate,  whose  right  extended  over  tlie  wliole,  Avithin  its 
proper  boundaries,  there  might  be  third  jjersons,  having 
rights  within  the  boundaries  also.  When  this  is  the  case 
it  is  often  popularly  (but  inaccurately)  said  that  the  owner- 
ship is  liiititt'd.  Oicnership  in  itself  is  an  ultimate  and 
indivisil^le  rig) it ;  if  a  person  is  owner  at  all,  he  is  simply 
owner,  he  cannot  be  something  more  or  less,  so  long  as  he 
retains  the  legal  title  at  all.  But  around  the  riyht  of  on ner- 
sJiij)  cluster  also  a  number  of  subsidiary  rights  and  enjoyments, 
some  of  which  can  be  broken  off,  so  to  speak,  and  come  into 
the  hands  of  other  persons.  Hence,  though  the  ownership 
remains,  the  enjoyment  of  it  may  be  either  absolute  and 
unfettered  or  may  be  limited.  One  obvious  way  in  which 
such  limitation  arises,  is  by  some  contract — such  as  a  lease, 
pledge,  or  mortgage,  or  loan  of  the  estate  ;  with  that  kind, 
however,  the  present  w'ork  is  not  concerned.  There  is  another 
class  of  rights  of  third  ])arties  which  do  not  arise  out  of  any 
lease  or  temporary  contract,  and  their  existence  often  causes  a 
very  considerable  limitation  of  a  forest  owner's  enjoyment  and 
control  of  his  property. 

4.  Rules  of  Protecting  Forest  Property. 

Before  discussing  the  nature  of  these  rights,  some  brief 
rules  may  be  given,  which  apply  to  the  protection  of  the 
forest  property  or  estate  as  such-;  to  secure  the  area,  general 
title,  and  legal  position  of  the  property. 

(a)  See  that  the  forest  is  regularly  and  permanently 
demarcated,  both  as  to  its  general  outer  boundaries  and  as 
to  all  inner  boundaries — which  mark  the  limits  to  which 
certain  rights  extend,  or  in  which  there  are  no  rights  other 
than  the  owner's. 

(h)  Provide  convenient  means  of  entrance  to  and  exit  from 
the  forest  and  its  various  compartments. 

(c)  Exercise  the  rights  of  ownership  in  the  forest,  especially 
near  its  outer  boundaries ;  let  no  one  have  an  excuse  for 
saying  it  could  not  be  known  that  any  one  was  in  possession, 
or  was  owner  of  the  place.  The  mere  fact  of  possession 
renders  the  assertion  of  ownership  much  stronger  before  the 
courts  of  law,  in  cases  of  disputed  ownership. 


FOREST    RIGHTS.  67 

(d)  Carefully  prevent  damage  to  the  estate,  its  roads, 
fences,  works,  etc.,  especially  if  caused  by  the  removal  of 
forest  produce. 

{(')  Carefully  watch  against  encroachments,  and  all  kinds 
of  forest  offences,  injury  to  boundary  pillars  and  other  marks. 

(/)  When  any  licences  or  concessions  are  allowed,  see  that 
this  is  always  done  by  written  or  printed  permission  so  worded 
as  to  make  it  clear  that  no  right  of  a  prescriptive  character 
can  arise. 

((f)  Exercise  any  rights  the  forest  estate  may  possess  over 
other  estates,  and  all  claims  to  labour,  or  payments,  all  rights 
of  receiving  help  in  ease  of  forest  fire  or  other  calamity,  or 
receiving  information  (which  may  be  imposed  by  the  forest  or 
other  law). 

Section  II. — General  Account  of  Forest  Eights  or 
Servitudes. 

1.  Nature  and  Origin  oj  Forest  Rights. 

As  already  stated,  it  frequently  happens  that  -persons 
(sometimes  individuals,  sometimes  legal  persons  or  corpora- 
tions) possess  rights  over  a  forest  (or  other)  property  which 
belongs  to  someone  else.  These  are  permanent  rights,  which 
have  nothing  to  do  with  a  contract,  or  temporary  lease,  mort- 
gage, etc.  In  that  case  the  forest  or  other  estate  over  which  the 
limited  right  exists  is  called  the  servient  estate — it  is  burdened 
with  the  right.  These  rights  are  called  by  various  names. 
The  Roman  lawyers  called  them  servitudes  (because  the 
burdened  property  was  made  to  serve  the  purpose  of  the 
holder  of  the  right).  In  English  some  were  called  easements 
{i.e.  one  kind  of  them  were  so,  of  which  presently),  others 
rights-of -common.  In  India,  the  Legislature  (abandoning  this 
distinction)  has  called  them  all  "  easements."*  Such  rights 
depend    partly    on  grants,   or   some   form    of   written    title, 

•  Origin  o/fonst  rights. — In  Germany  these  rights  often  arose  out  of  the  old 
agricultural  cuiuniunities  whose  territory  or  Mark  had  a  portion  or  borderland  of 
waste  and  forest  which  (in  some  sense,  at  any  rate)  belonged  to  the  inhabitants. 
From  the  time  of  Charlemagne  these  border-forests  were  appropriated  by  the 
empire  or  by  powerful  landowners  and  town  corporations,  and  the  original  owners 
became  mere  right- holders.     Waste  lands  attached  to  villages  in  India  have  also 

F    2 


6H  PROTECTION    AGAINST    MAN. 

perhaps  a  judgment  of  some  Court,  and  partly  on  ^Yhat  is 
called  prescription.  By  this  latter  term  \ve  mean,  that 
though  the  exact  origin  is  not  known,  j'et  as  a  matter  of 
fact  the  right  has  been  exercised  for  a  long  time — the  term 
of  years  (usually  20  or  30)  is  fixed  by  the  law  of  each  country 
— and  also  has  been  exercised  openly  (not  by  fraud  and 
unknown  to  the  owner),  peaceably  (not  by  violence),  and  as  of 
right  (not  by  mere  leave  or  sufferance,  acknowledging  that 
the  owner  could  put  a  stop  to  the  practice).  When  these 
conditions  concur,  there  is  a  full  legal  right  by  prescription. 
It  is  also  possible  the  rights  may  l)e  regarded  as  (in  a  wa}') 
prescriptive,  by  reason  of  their  being  admittedly  matters  of 
ancient  local  custom  or  on  other  equitable  grounds,  even  when 
the  precise  terms  of  a  legal  prescription,  as  above  stated,  are 
not  established. 

2.  Rights  or  Servitudes  classified  into  Kinds. 

The  lawyers  in  various  countries  have  classified  these  rights 
in  different  ways  in  consequence  of  particular  legal  distinc- 
tions. For  example,  such  rights  are  said  to  be  negative 
when  the  estate  which  bears  the  right  is  merely  under 
the  continuous  obligation  not  to  do  something — i.e.  not  to  dig 
a  hole  so  as  to  endanger  the  right-holder's  foundations,  not  to 
stop  the  flow  of  water,  etc. ;  and  p)ositive,  when  it  is  obliged 
to  allow  the  right-holder  to  do  or  take  something,  as  to  drive  his 
cattle  across  a  field,  .take  wood,  or  drive-in  pigs  to  feed  on 
acorns,  etc.  Rights  are  also  said  to  be  continuous  or  dis- 
continuous  (intermittent) ;  the  former  in  their  nature  are 
continually  in  operation  at  every  moment  (as  a  right  to  light 
and  air  by  ancient  windows*) ;  the  latter  are  used  from  time 

had  something  of  the  same  history  ;  but  uudcr  the  effects  of  the  land  settlements 
such  areas  have  mostly  been  freely  given  over  to  the  villages.  In  the  Garo  Hills 
(Assam),  where  tribal  settlements  in  the  ancient  model  still  can  be  observed,  it 
is  only  within  the  last  40  years  that  fighting  has  ceased  when  one  village  group 
tried  to  encroach  on  the  border-forest  of  the  next.  Forest  rights  also  arose  by 
grant  of  the  baron  or  lord  :  and  still  more  grow  up  by  local  custom,  and  long  user 
of  the  neighbours,  partly  because  the  modes  of  agriculture  then  known  suggested 
forest  grazing,  pannage,  etc.,  as  the  most  desirable,  and  wood  fuel  was  required 
before  coal  was  obtainable.  In  those  times,  too,  forests  were  abundant  in  com- 
parison with  the  number  of  the  population  :  and  no  one  cared  to  interfere  with 
people  habitually  taking  what  was  so  abundant  and  had  so  little  value. 
•  And  in  general  all  negatife  servitudes  are  necessarily  continuous. 


FOREST    RIGHTS.  69 

to  time,  either  at  fixed  intervals  {e.f/.  a  right  to  have  10  beams 
for  repairs  once  every  5  years),  or  on  occasion  (as  to  cut 
l)rushwood  for  fuel  when  wanted).  This  latter  feature  (dis- 
continuity) may  give  rise  to  a  further  question,  which  will  be 
noticed  presently. 

On  the  sul)ject  of  classiHcation  of  rights  of  user,  only  two 
points  have  a  practical  bearing  on  protection.  One  concerns 
the  nature  of  the  right,  the  other  concerns  the  nature  of  the 
right -liolder. 

As  regards  the  nature  of  the  right,  there  is  an  obvious 
distinction  between  rights  which  (whether  negative  or 
positive)  imply  only  some  use  of  the  servient  estate  (as 
walking  over  it,  letting  water  flow  across  it,  having  the 
support  of  soil  for  foundations,  having  a  beam  resting  on  a 
(servient)  neighbouring  wall,  etc., — in  all  which  cases  nothing 
is  taken  out  of  or  from  the  servient  estate  ;  and  those  rights 
which  do  take  something  ;  e.g.  rights  of  pasture,  wood  rights, 
rights  to  dig  sand,  litter,  etc.).  [It  is  the  former  only  that  the 
English  lawyers  call  easements  ;  the  latter  are  rights-of -common, 
or  profits  a  prendre  in  older  books.]  And  then  as  to  the 
holder  of  the  right :  this  may  be  a  person  A.  B.  and  his  heirs  ; 
it  is  always  understood  that  the  person  cannot  alienate  the 
right  or  servitude.  Such  rights  are  said  to  be  personal  rights, 
or  as  English  lawyers  say,  riglits  in  gross.  But  very  often  the 
right  is  held  not  by  a  person  (natural  or  artificial)  as  such,  but 
by  a  certain  house,  farm,  or  other  l)uilding  or  estate  ;  so  that 
the  right  is  exercised  by  the  person  who  happens  to  be  the 
holder  of  the  estate  or  farm,  etc.,  for  the  time  being.  Should 
the  present  holder  go  away  and  sell  the  farm,  etc.,  he  would 
cease  to  have  any  right ;  but  the  right  must  pass  with  the 
farm  by  sale.  Eights  of  this  kind  are  called  real  rights  {real 
in  a  technical  sense),  and  the  estate,  house,  farm,  etc.,  to 
which  they  are  attached  is  called  the  dominant  estate,  just  as 
the  estate  which  bears  the  right  is  called  the  servient  estate. 

Different  systems  of  law  have  different  ideas  regarding 
these  rights.  For  instance,  in  France  and  Germany  forest 
rights  (to  pasture,  wood,  etc.)  are  always  real  rights — they  are 
always  attached  to  some  farm,  building,  etc.,  for  the  benefit 
of  which  the  right  exists.     But  this  is  not  always  the  case  in 


70  PROTECTION    AGAINST    MAN. 

Britain  or  in  India  (except  in  some  few  cases  which  in  their 
nature  imply  some  (dominant)  house  or  building  or  land  to 
which  the  right  is  attached)  ;  it  is  quite  possible  for  an 
individual  to  have  a  prescriptive  right  as  such  individual.* 
It  is  not  necessary  then  to  pursue  this  classification  further, 
except  to  be  sure  that  when  a  right  is  so  attached,  the  record 
of  it  makes  it  quite  clear  exactly  where,  what  and  of  what 
extent,  is  the  house,  farm,  or  estate,  which  is  the  domifiaut  or 
right-holding  property. 

It  need  only  be  mentioned  that  jyersonal  rights  may  be 
granted  or  become  prescriptive  to  a  person  and  his  heirs  for 
ever,  or  may  be  (granted)  for  life  or  lives  only. 

3.  Forest  RifiJits  irliicli  are   Undefined. 

Keturning  for  one  mom<'nt  to  the  preserijitire  oripiii  of 
rights,  one  very  important  matter  has  to  be  noticed.  Such 
rights  are  nearly  always  undefined  or  indefinite — indeed,  it 
is  possible  that  some  rights  by  the  terms  of  a  grant  are  also 
left  undefined  ;  but  most  commonly  it  is  prescriptive  rights 
that  are  so. 

The  custom  is  that  the  right-holder  may  graze  "  his  cattle" 
in  forest  A.  (how  many  and  of  what  kind,  and  at  what  season 
is  not  stated) ;  or  that  he  may  have  power  to  build  and  repair 
"  his  house  "  ;  or  he  has  "common  of  estovers" — a  right  to 
fuel — but  of  what  kind  (brushwood  or  billets)  and  for  what 
purposes,  does  not  expressly  appear. 

In  all  systems  of  law  there  are  rules  for  determining  how 
such  undefined  rights  can  either  be  brought  formall}'  to  record 
in  a  definite  shape  (e.g.  the  Indian  Forest  Act),f  or  at  least 

*  A  brief  note  may  be  useful  as  to  village  rights  in  Inilia  :  it  cannot  be  said, 
or  can  only  be  true  in  particular  cases,  tliat  a  rilluge  is  in  any  sense  a  corpora- 
tion, or  that  it,  regarded  as  a  single  (artificial)  person,  can  hold  rights  of 
user  or  common  ;  nor  can  it  in  general  be  regarded  as  a  single  dominant  estate 
possessing  riglits.  If  (though  not  warranted  by  the  Indian  forest  law)  a  right  is 
set  down  in  a  public  record  as  existing  in  favour  of  "village  C." — this  merely 
means  that  all  inhabitants  (or  j)erhapsonly  all  bindhnldeis)  of  village  C,  for  the 
time  being,  can  exercise  the  right  in  question. 

t  In  all  fully-constituted  State  forests  in  India,  the  law  reijuircs  every  right 
claimed  to  be  brought  before  a  public  officer  appointed  for  that  purpose  and  not 
only  recorded,  but  made  as  definite  in  nuTuber,  extent,  kind,  etc.,  as  circumstances 
allow. 


forp:st  rights.  71 

there  are  provisions  for  fixing  the  number  of  cattle,  quantity 
of  timber  or  firewood,  etc.,  to  be  claimed  under  the  right. 
These  principles  are  detailed  in  law  manuals.*  No  system  of 
law  allows  such  a  thing  as  an  unlimited  right — for  that  might 
swallow  up  the  entire  ownership — a  thing  contrary  to  the 
very  nature  of  a  right  of  this  kind  which,  it  should  be. always 
remembered,  is  a  permanent  right  (not  arising  out  of 
contract)  of  one  person  or  estate,  which  exists  over  the 
property  Of  another  person,  to  have  some  use,  or  take  some 
part  of  the  produce  of  the  other  property. 

It  is  true  that  sometimes  a  number  of  separate  rights  may 
exist,  the  aggregate  demands  of  which  form  a  serious  burden 
on  the  forest  property  ;  but  there  is  no  infringement  of  the 
principle.  It  is  also  to  be  mentioned  in  passing,  that 
sometimes  there  is  a  kind  of  right  over  property  of  a 
special  nature,  called  the  usufruct,  which  implies  that  the 
whole  of  the  normal  produce  and  the  general  enjoyment  of 
the  property  passes  for  life  to  the  usufructuary ;  but  even 
then,  the  holder  of  such  a  right  is  not  owner,  nor  can  he  do 
anything  that  alters  or  injures  the  property  in  its  substance, 
or  affects  the  ownership  right! — a  fortiori,  therefore,  a  mere 
holder  of  a  right-of-common  is  bound  to  respect  the  estate 
on  which  his  right  subsists,  and  treat  it  civiliter  et  modeste 
according  to  Eoman  Law,  or  en  ban  pere  de  famille,  in 
French  Law,  and  cannot  demand  an  unlimited,  or  abusive 
enjoyment  of  it. 

4.  How  Forest  Eights  may  Terminate. 
As  we  have  considered  how  such  rights  may  grow  up,  so  a 
few  words  will  be  appropriate  as  to  how  they  came  to  an  end, 

•  For  instance,  in  Danckcliuann's  "  Abliisung  uiul  Regelung,"  3  vols.,  Berlin, 
1880.     Badcu-Powell,  "  Forest  Law,"  p.  318,/. 

t  The  usufruct  is  always  for  life  (see  Broillanl,  "  Le  Traitement  des  Bois  en 
France."  Paris  :  Berger,  Levrault  et  Cie.— i.*'.  1894.  pp.  627— 6.>4).  If  there  is  a 
proscribed  worhinfj-phin  the  usufructuary  must  carry  it  out  and  only  take  such 
produce  as  comes  within  its  directions,  and  he  must  carry  out  all  works,  such  as 
new  planting,  sowing,  keeping  forest  works  and  roads  in  order.  Such  a  usufruct 
arises  in  the  case  of  entailed  forests,  or  those  comprised  in  a  family  settlement ; 
also  it  may  be  that  part  of  the  glebe  lands  in  a  rectory  in  which  the  parson  has 
a  life-interest,  is  stocked  with  trees,  and  may  come  under  this  head.  By  English 
law,  a  rector  may  cut  underwood  on  his  glebe  land  in  accordance  with  the  usual 
rotation,  but  may  fell  timber  trees  only  when  they  are  mature. 


72  PROTECTION    AGAINST    MAN. 

(a)  It  may  be  iialmalb/  :  as  where  the  dominant  estate  dis- 
appears {e.[i.  river  dihivion),  or  where  the  personal  right-holder 
dies  without  heirs. 

(b)  It  may  be  that  the  forest  is  mia)»le  to  satisfy  the  require- 
ments of  the  right;  here  the  right  must  remain  in  abeyance, 
till  the  forest  has  recovered  from  the  calamity  which  caused 
the  inability.  Where  the  rights  are  permanently  in  excess  of 
the  yield-power  of  a  normal  forest,  then  the  law  usually  provides 
express  terms  for  dealing  with  the  difficulty.* 

(c)  When  the  right-holder  becomes  (l)y  will,  purchase,  etc.) 
owner  of  the  servient  estate,  or  where  the  dominant  estate 
is  acquired  by  the  servient  estate,  the  lesser  right  merges  into 
the  greater. 

(d)  Where  the  right-holder  .Hiihinits  to  an  interruption,  or 
acquiesces  in  an  act  on  the  part  of  the  servient  owner  who  pre- 
vents the  exercise  (of  course  having  notice  of  the  interruption), 
the  right  will  be  lost  if  no  action  is  taken  for  one  year  A  It 
may  be  that  the  right-holder  himself  discontinues  or  intermits 
the  exercise  of  his  right.  In  England,  it  is  a  question  of  fact 
for  the  jury,  whether  the  discontinuance  was  long  enough  or 
under  such  circumstances,  as  to  give  rise  to  a  conclusion  that 
the  right  was  abandoned.  In  India,  the  matter  has  been  settled 
by  legislation  (Act  XV.  of  1877,  sect.  26  Exp.).  Two  years' 
intermission  (under  the  conditions  stated  in  the  Act)  will  cause 
the  right  to  terminate. 

Of  course  in  all  cases,  as  a  right  can  be  gained  by  prescription 
so  it  can  be  lost  by  complete  non-user  for  the  whole  legal  i)eriod 
of  prescription. 

(e)  Lastly,  the  right  may  terminate  when,  either  by  friendly 
agreement,  or  (if  the  law  prescribes)  by  compulsory  process, 
the  right  is  commuted  or  bought-out  on  paying  compensation.! 

*  See  Baden-rowell,  "Forest  Law,"  pj).  2!t3,  'MV.),  :{7S. 

t  For  England,  see  2  &  H  Will.  4,  c.  71.  The  Indian  law  is  similar:  see 
sect.  2G,  Act  XV.  of  1877. 

I  Explained  in  Danckclmann's  "  Die  Ablosung  und  Rcgolung  der  Waldgrund- 
gerechtigkeiten."  Cooke's  "  Wingrove  on  Enclosures,"  1864  (referring  to  the 
multitudinous  and  complicated  Enclosure  Acts).  Baden-I'owell,  "  Forest  Law," 
pp.  367 — 893  (where  an  aljstract  of  the  German  law  is  given).  Meaume,  "Usage 
Forestier  "  (reprinted  from  the  "  Repertoire  de  Legislation,"  Nancy,  1861). 


FOREST    RIGHTS.  .  7:3 

5.  Practical  Principles  of  Lair  rcfiardinr/  Forest  liitihts. 

The  following  short  statement  of  legal  principles,  all  of 
which  are  based  on  broad  rules  recognised  in  all  systems  of 
civilised  law,  will  be  found  useful : — 

(a)  There  can  be  no  such  thing  as  a  right  to  destroi/  the 
estate  or  do  wanton  mischief  {e.ff.  burn  a  forest). 

(h)  The  right-holder  is  in  no  sense  a  part-owner  of  the 
forest.  When  a  part  of  the  forest  is  separated  and  given  over 
to  him,  such  a  proceeding  is  at  the  option  of  the  owner, — as  a 
means  of  compensating  for  and  getting  rid  of  the  right. 

(f)  The  right  is  always  a  limited  one  ;  it  can  be  exercised  so 
only  if  while  fully  and  fairly  enjoyed  it  does  not  attack  the 
suJ)staiiee  of  the  forest :  it  can  never  exceed  the  normal  regular 
yield  of  the  forest  nor  its  capacity  to  bear  the  right  without 
deterioration  in  the  case  of  grazing,  soil-litter,  etc.  etc. 

(d)  When  a  right  is  undefined  in  its  character,  and  has  not 
been  reduced  to  definite  terms,  it  is  always  understood  to  be 
limited  to  the  actual  needs  of  the  person,  or  the  dominant  estate 
(as  the  case  may  be),  in  his  or  its  normal  condition  as  it  was 
when  the  right  originated.  If  a  peasant  has  a  right  to  wood 
for  "building  his  house,"  it  means  such  a  house  as  is 
usual  in  the  locality,  not  a  large  villa  or  whole  range  of  farm- 
buildings.* 

(e)  The  right  must  be  exercised  so  as  to  interfere  as  little  as 
possible  with  the  regular  management  proper  to  forests  of  the 
normally  existing  class  or  kind;  it  cannot  prevent  the  restora- 
tion of  an  ill-used  forest,  or  the  proper  planting  operations  and 
production  of  3'oung  growth. 

(/)  On  the  other  hand,  the  forest  owner  cannot  claim  to 
alter  the  character  of  the  forest,  or  its  general  destination 
so  as  to  affect  rights ;  and  where  one  mode  of  proper  work- 
ing would  provide  for  the  rights  while  another  would  not, 
the  owner  must  make  his  working-plan  so  as  to  provide  for 
the  rights. f 

*  See  Baden-Powell,  "  Forest  Law,"  p.  290  ./f,  328. 

t  See  "  Forest  Law,"  p.  294. /f.  In  England  we  have  a  recent  example  which 
illustrates  the  rnle  that  a  forest  owner  cannot  alter  the  entire  destination  and 
character  of  his  estate  to  the  prejudice  of  right-holders  ;  and  at  the  same  time  is 
a  rare  instance  of  forest  rights  being  beneficial  (from  a  forest  point  of  view).  In 
the  case  of  Epping  Forest,  the  right-possessed  by  the  commoners  to  lop  the  trees 


7+  •  PROTECTION    A(4AINST    MAN. 

6.   TJic  Disadvantages  Arisituj  from  Forest  Servitudes. 

The  chief  disadvantages  to  forests,  from  the  existence  of 
rights-of-common  are : — 

(a)  Limitation  of  the  owner's  power  of  managing  the  forest 
in  the  best  possible  manner,  or  of  converting  it,  and  so  forth. 
An  insuperable  obstacle  to  systematic  management  in  English 
woodlands  subject  to  rights-of-common,  is,  that  they  cannot 
be  enclosed,  or  fenced.  Such  woodlands  pay  no  rates,  and 
thus,  the  general  public  has  to  pay  for  the  privileges  of  the 
right-holders,  often  a  few  neighbouring  land-owners,  who 
obtain  a  higher  rental,  than  they  would  otherwise,  from 
the  farmers,  or  cottagers,  who  exercise  the  rights. 

Some  servitudes  affect  the  control  more  than  others,  and  it 
is  noteworthy,  that  it  is  generally  not  any  one  right  that  is 
objectionable ;  the  difficulty  arises  from  the  aggregate  demand 
for  a  number  of  right-holders,  both  as  to  the  quantity  of  pro- 
duce, area  of  grazing,  etc.,  which  they  require,  and  also 
the  number  of  persons  introduced,  to  graze  flocks,  gather 
wood,  etc. 

{h)  Even  rights-of-way  and  other  rights  which  tahc  nothing 
from  the  forest,  give  occasion  to  accidental  trespass,  to  forest 
fires,  and  perhaps  to  wilful  offences. 

(c)  The  forest  owner  is  tempted  to  be  less  careful  of 
his  forest,  and  is  deterred  from  expending  capital  on  its 
improvement. 

{d)  Both  the  labour  and  cost  of  protection  are  considerably 
increased  when  forest  rights  are  numerous. 

was  enforced  when  the  lords  of  the  manors  wished  to  enclose  the  forest  areas, 
included  in  their  manors,  aiM  had  (jven  {)roceeded  so  far  as  to  clear  a  thousand 
acres  of  forest  and  subdivide  it  into  buildinf^  allotments.  They  claimed  the 
power  to  purchase  the  right  of  lopping  from  the  right-holders  within  their  own 
manors.  The  right-holders,  on  the  other  hand,  claimed  that  their  right  extended 
over  the  whole  forest,  and  not  over  any  particular  manor,  and  this  view  of  the 
matter  was  eventually  accepted  by  the  High  Court  of  Justice  after  a  protracted 
judicial  inquiry.  Thus  it  was  decided  that  the  lords  of  the  manors  could  not 
free  their  respective  manors  from  the  rights  without  satisfying  all  the  right- 
holders,  in  whatever  manor  they  might  reside.  This  decision  saved  Epping 
Forest  from  being  converted  into  building-sites,  and  the  City  of  London  even- 
tually purchased  all  the  manorial  and  lopping  rights  in  the  forest,  the  latter  for 
£7,000,  and  now  only  rights  of  pasture  and  pannage  are  exercised  by  the 
commoners. 


FOREST    RIGHTS.  ,         75 

(e)  And  so  are  the  risks  of  offences,  and  forest  fires. 

(/)  Control  of  the  right-holders  involves  much  otherwise 
unnecessary  work  both  in  the  office  and  forest. 

ig)  The  revenue  from  a  forest  is  reduced,  not  only  by  loss 
of  produce,  but  also  by  degradation  of  the  soil  owing  to 
pasture  or  removal  of  litter. 

(/<)  Disputes  arise,  and  risk  of  litigation,  and  of  ill-feeling 
culminating  in  revengeful  attempts  to  burn  or  otherwise 
injure  the  forest.  Forest  right-holders  are  also  tempted  to 
presume  on  their  position  and  encroach  on  the  rights  of 
the  owners.* 

Looking  at  the  question  from  the  broad  point  of  view  of 
political  economy,  forest  servitudes  encourage  extravagance  in 
the  use  of  wood,  and  establish  a  backward  style  of  agriculture, 
as  regards  the  use  of  litter  for  manure,  loppings  for  fodder, 
and  forest  grazing,  which  may  in  the  end  overtax  the  forest 
and  result  in  serious  forest  destruction  and  consequent 
injuries  to  the  country,  from  floods,  landslips  and  other 
physical  evils  against  which  forests  are  a  natural  and  often 
effective  protection. 

The  degree  of  danger  incurred,  irrespectively  of  the  character 
of  the  servitude,  depends  on  the  conditions  of  the  locality  and 
the  density  of  the  standing  crop.  A  completely  stocked  wood, 
on  favourable  site  (as  regards  slope,  exposure,  etc.),  and 
\Yith  a  mild  climate,  suffers  (proportionately)  least  of  all. 

7.  Equitdhh  Principhs  in  Dealvig  witJi  RigJtts. 

"Where  forest  laws  exist,  there  is  usually  provision  for  the 
record  of  all  forest  rights,  and  for  the  defii^tion  of  those  which 

*  In  tlie  New  Forest,  the  present  tendency  is  for  commoners  to  exaggerate  their 
rights  at  the  expense  of  those  of  the  Crown  ;  and  in  1 894  they  attempted  to  prevent 
the  Crown  from  erecting  a  saw-mill  and  exercising  other  rights  of  ownership  in 
the  forest.  In  the  Forest  of  Dean,  since  IS.")?,  grazingby  sheep  is  largely  practised  ; 
and  it  remains  to  be  seen  whether  the  Commissioners  of  Woods  and  Forests  will 
be  able  to  stop  this  practice,  which  is  fast  ruining  the  Forest  of  Dean,  for 
centuries  the  most  productive  oak  forest  in  Britain.  Sheep  are  not  beasts-of- 
common  by  English  law  (see  "  Williams  on  Rights  of  Common,"  1880,  p.  232), 
and  no  prescriptive  right  t(j  sheep-grazing  can  arise  in  Flrigland  :  the  (juestion  is 
whether  local  feeling  in  favour  of  the  commoners  will  be  allowed  to  override 
the  national  interest  in  this  matter. 


76  •  PROTECTION    AOxAINST    MAN. 

are  claimed  in  indefinite  terms.  It  is  hardly  necessary  to 
remark,  that  every  claim  must  be  proved  :  the  natural  pre- 
sumption is  that  the  owner's  enjoyment  is  not  limited — it  is 
for  the  person  who  asserts  a  right  to  any  use  or  produce 
limiting  the  enjoyment,  to  prove  it. 

The  forest  estate  should  always  possess  the  means  of 
referring  to  documents  conferring  rights,  and  if  there  is  a 
serious  doubt  about  terms,  the  sooner  a  judicial  decision  is 
obtained  the  l)etter.  Nothing  is  gained  by  "  letting  sleep- 
ing dogs  lie" — for  in  this  case  uncertain  rights  are  not 
"  sleeping "  ;  they  always  tend  to  grow  more  difficult  to 
settle,  and  are  ultimately  fixed  in  a  form  that  perliaps  was 
never  .contemplated. 

It  may  be  confidently  stated  that  where  indcjinxtc  rights 
exist  all  rational  management  is  impossible  until  they  are 
properly  defined. 

The  foiest  owner  has,  in  general,  a  right  to  sluire  in  the 
produce  of  the  forest,  along  with  the  right-holders.* 

Attention  sliould  be  paid  (p.  64)  to  the  legal  principles 
stated,  especially  as  regards  the  limitation  of  undefined  rights 
to  the  actual  needs  of  the  person  or  dominant  estate,  and  to 
there  being  no  right  (in  general)  to  a  surplus  which  may  be 
sold  or  turned  to  an  extra  profit.  Also  to  the  Iwdt  that  cannot 
be  exceeded,  when  the  yield-power  {jhyssihilitt')  of  the  forest  is 
in  question. 

On  the  other  hand  it  must  be  borne  in  mind  that  while  the 
forest  right-holder  has  his  obligations  and  must  submit  to 
those  reasonable  restrictions  which  are  necessitated  by  proper 
conservative  management,  the  forest  owner  has  a  duty  on  his 
side.  He  cannot  adopt  special  methods  of  management  (how- 
ever desirable  in  themselves)  that  would  destroy  the  rights ; 
and  the  working-plans  should  be  prepared  with  the  express 
object  of  providing  for  such  rights  as  exist,  and  which 
(especially  in  certain  localities)  are  almost  i)idis2)C)tS(ihle  to  the 
welfare  of  the  present  population.! 

New  rights  ought  never  to  be  allowed  (by  neglect,  etc.)  to 

*  See  Badcii-rowell,  "Forest  Law,"  ]).  I?!)?. 

t  See  "Forest  Law,"  p.  29i.//',  where  the  correlative  right  antl  duties  of  the 
right-holder  and  forest-holder  are  discussed. 


FOREST   RIGHTS.  77 

groiv  tip  in  forests  even  when  there  is  no  forest  law  which 
expressly  forbids  such  growths.  Nor  can  the  State  or  other 
owner  grant  new  forest  rights  to  the  prejudice  of  old  and 
existing  ones. 

8.  Protectire  Measures. 

From  the  point  of  view  of  the  forest  owner,  the  foUoMing 
measures  are  desirable  :-^ 

(a)  Clear  demarcation  of  the  portions  of  the  forest  burdened 
with  rights,  and  those  free  from  them  or  closed  against 
them ;  and  maintenance  of  distinct  boundary  lines ;  also 
indication  by  ditches  or  sign-posts,  etc.,  of  lines  of  right-of- 
way  for  cattle,  etc. 

{b)  Careful  record  of  rights-of-way,  etc.,  use  of  water,  as 
well  as  those  to  produce.  Where  there  is  a  forest  law,  it  is 
probably  provided  how  this  is  to  be  done.  Besides  which  all 
working-plans  of  the  forest  must  contain  a  schedule  of  the 
rights  showing : — 

(i)  Title-deed,  or  other  origin  of  the  right. 

(ii)  Exact  description  of  personal  holder  or  dominant  estate  ; 
and  the  exact  name,  etc.,  of  the  servient  estate  or  part  of  it 
affected. 

(iii)  The  extent  of  the  right,  kind,  number,  quantit}',  quality, 
season  of  exercise,  etc.,  etc. 

(iv)  The  mode  and  conditions  of  exercise,  and  whether  any 
particular  duty  is  laid  on  either  side  (e.g.  providing  a  compe- 
tent herdsman  for  the  cattle,  providing  cattle-bells,  or  the 
forest-owner  maintaining  culverts,  etc.,  for  a  roadway). 

(v)  Any  payments,  or  returns  in  labour,  due  to  the  forest- 
owner  for  the  exercise  of  the  right. 

(vi)  A  notice  of  any  obscure  or  disputed  points. 

(c)  Careful  watching  of  the  exercise  of  forest  rights  by  the 
forest  guards  and  inspecting  offtcers.  But  the  caution  already 
given  about  irritating  and  vexatious  interference  should  be 
borne  in  mind. 

It  is  only  necessary  to  add  that  where  the  rights  are  such 
that  the  forest  is  seriously  threatened,  then  efforts  must  be 
made  to  get  rid  of  them  by  commutation  or  cantonment.  The 
rights    should   either  be   purchased    from    the    right-holders 


78  PROTECTION    AGAINST    MAN. 

(commutation),  or  a  portion  of  tlie  forest  set  apart  in  perpetuit}' 
as  a  common  for  their  exercise  and  handed  over  as  property  to 
the  body  of  right-holders  (cantonment),  and  the  remainder  of 
the  forest  declared  free  of  all  rights.  Such  commutation,  or 
cantonment  of  rights  in  a  State-forest  rec^uire  the  sanction  of 
an  Act  of  the  Legislature. 


Section  III. — Special  Account  of  the  several  Forest 

lilGHTS. 

This  section  is  concerned  with  some  rules  applica])le  to  each 
particular  kind  of  right,  for  which  purpose  the  following  list 
of  "  forest-rights  "  is  given  : — 

1.   Wood'Rifihts. 

(a.)  Building-timber. 

(b.)  Wood  for  industrial  purposes  and  agricultural  implements. 

(c.)   Firewood. 

(d.)  Softwoods. 

(e.)   Dead,  or  fallen  wood. 

(/.)  Lop  and  top. 

(^.)    Stumps  and  roots. 

(/i.)   Windfalls  and  broken  trees. 

(t.)    Dead  standing  trees. 

2.  liii/ltts  to  Minor  Produce, 

(a.)  Bark. 

(b.)  Turpentine  and  tar. 

(c.)  Leaf-fodder. 

(d.)  Grass  (cutting  or  gathering). 

(e.)  Pasture. 

(/.)  Collecting  acorns  and  beech-mast. 

(g.)  Pannage, 

(/t.)  Litter. 

(i.)  Quarrying  or  digging  pits  for  sand,  gravel,  turf,  etc. 

(j.)  Gathering  berries,  wild  fruit,  hazel-nuts,  fungi,  etc. 

(/i.)  Shooting  and  fishing. 


FOREST    RIGHTS.  79 

•    3.  Sundry  lUgltts  {Easements). 

(a.)  Eights-of-way. 

(b.)   Eights  to  water,  water-cliannels,  use  of  springs  or  wells, 

to  water  cattle,  at  streams,  etc. 
(c.)    Eights  to  float  timber. 
{(l.)  Eight  to  bm-ii  charcoal,  to  stack  wood,  etc. 

1.   Wood-Eights. 

Under  the  above  term  is  understood  either  a  right  to  claim 
from  a  forest  a  certain  fixed  quantity  of  wood,  or  as  much  as 
may  be  necessary  for  certain  purposes.  Such  rights  may,  or 
may  not,  be  subject  to  certain  payments  to  the  owner  of  the 
forest.  It  is  generally  stated  what  kind  of  wood  is  the  subject 
of  the  right,  thus,  it  may  be  building-timber,  limber  for 
implements,  or  firewood.  Sometimes  the  title-deed  merely 
mentions  "  necessary  wood,"  under  which  term  firewood  is 
generally  understood.  The  forest  manager  has  the  right  of 
delivering  the  wood,  and  certain  days  may  be  fixed  for  its 
removal. 

A  defined  right  to  wood  is  fixed  as  regards  quantify  and 
form,  and  sometimes  as  regards  species. 

When  the  species  is  not  mentioned,  the  right-holder  must 
be  satisfied  with  wood  of  the  prevailing  species,  provided  it  is 
suitable  for  the  purpose  required. 

An  undefined  right  to  wood  is  limited  to  the  requirements  of 
the  right-holder  or  the  dominant  estate ;  for  instance,  the  actual 
house  of  the  rigl it-holder,  not  his  sheds  and  farm-buildings 
(unless  those  are  eqiTitably  included). 

The  owner  of  the  burdened  forest  must  manage  it  so  that 
the  wood  which  is  the  subject  of  the  right  may  continue  to  be 
produced.  For  instance,  where  there  is  a  right  to  building- 
timber,  the  forest  cannot  be  converted  to  coppice. 

The  right-holder  may  not  sell  his  wood,  but  must  use  it  for 
the  purpose  for  which  it  has  been  granted  to  him. 

a.  Building-Timber. 

The  supply  of  building  timber  to  right-holders  should  be 
fairly  proportional  to  the  number  and  size  of  the  buildings 


80  PHOTECTION   AGAINST    MAN. 

which  existed  at  the  time  of  the  acquisition  of  the  right.  Often 
the  right  appHes  only  to  wood  for  the  exterior  of  the  house, 
hut  may  include  wood  for  wainscots,  windows  and  doors. 

When  repairs  to  a  huilding  become  necessary,  a  regular 
estimate  of  the  requisite  amount  of  timber  should  be  drawn 
up  ;  and  the  wood  must  be  used  within  a  fixed  period.  When 
a  new  house  is  being  built,  all  still  serviceable  wood  from  the 
old  house  must  be  deducted  from  the  estimate.  It  is  usual 
for  the  right-holder  to  pay  the  cost  of  extraction  of  the  wood, 
even  though  he  pays  nothing  for  the  wood  itself.  In  the 
Himalayan  forests,  right-holders  usually  fell  the  trees  and 
convert  the  timber  for  themselves ;  in  some  cases  the  right- 
holder  is  allotted  annually  a  certain  number  of  trees  for  house- 
repairs  or  building ;  in  other  cases  the  right-holder  is  put  down 
as  being  entitled  to  what  is  needed  on  application,  for  the  par- 
ticular work.  Account  has  here  to  be  taken  of  the  ignorance 
of  the  people,  and  their  ancient  but  wasteful  habit  of  preparing 
beams  with  the  axe  or  adze — chipping  away  a  whole  stem  for 
one  beahi.  By  loan  of  saws,  and  by  issuing  suitable  beams 
ready  prepared,  it  may  be  possible  to  overcome  this  defect, 
which  leads  of  course  to  much  waste  of  material. 

The  work  of  the  forest  staff  is  considerably  burdened  by 
rights  to  building-timber,  as  the  correctness  of  the  estimates 
has  to  be  tested,  and  the  amount  of  wood  granted  to  be  entered 
on  special  registers.  It  is  clearly  the  duty  of  forest  officers 
who  manage  large  areas  of  State  or  municipal  forests  subject 
to  rights  for  building-timber,  to  know  thoroughly  the  customary 
forms  of  building  of  the  locality  and  the  proper  dimensions  of 
beams  and  other  timbers  used  in  the  construction  of  houses, 
or  they  may  be  called  upon  to  grant  much  laiger  quantities  of 
timber  than  is  necessary  in  particular  cases. 

b.   Wood'/ar  Industrial  Purposes. 

This  right  (as  claimed)  may  be  defined,  or  not,  in  its  nature 
and  extent.  In  general,  it  comprises  timber  required  for 
ordinary  agricultural  and  domestic  objects,  such  as  wood  for 
carts,  ploughs,  hop-poles,  vine-props,  etc.  Wherever  the  right 
is  undefined,  the  quantity  should  be  fixed,  so  as  to  correspond 
to  the  amount  required  at  the  time  of  acquisition  of  the  right, 


FOREST    RIGHTS.  81 

extent  of  hop-garden,  vineyard,  etc.  This  right,  if  indefinite, 
interferes  greatly  with  the  development  of  the  revenue  of  a 
forest. 

^  r.  Firewood. 

Rights  to  firewood  (as  claimed)  may  he  either  defined  or 
indefinite,  and  in  the  latter  case  the  amount  granted  would  be 
only  what  is  required  for  the  household  of  the  right-holder, 
including  such  ordinary  household  requirements  as  heating, 
cooking,  washing,  baking,  drying  fruit,  etc.  Requirement  for 
industrial  purposes  such  as  distilling,  etc.,  is  not  included. 
As  a  rule,  the  wood  is  prepared  by  oi'der  of  the  owner  of  the 
forest,  and  must  be  taken  from  all  classes  of  fireM'ood  in  due 
proportion,  split  and  round  wood,  dead  wood,  stump-wood 
and  faggots.  Occasionally  the  right-holdeu  is  permitted  to 
cut  and  remove  the  wood,  esj^ecially  where  it  is  brushwood  or 
small  coppice  stuff. 

In  case  a  forest  burdened  with  this  right  should  be  damaged 
by  some  calamity  (storm,  insects,  etc.),  which  iiauses  an 
excessive  yield  in  any  particular  year,  then  several  years'  supply 
of  firewood  may  be  granted  to  the  right-holder,  in  advance, 
but  the  latter  cannot  claim  this  as  a  right. 

d.  Soft/roods. 

Where  the  right  is  to  "  softwoods,"  termed  in  France  bois 
blancs,  in  Germany,  Weichholz,  the  question  is  to  decide  on 
the  meaning  of  the  term.  It  may  be  interpreted  as  including 
inferior  softwood  species  which  are  not  the  object  of  the 
management  of  the  forfest,  and  therefore  only  appear  in  trifling 
quantity,  and  can  never  get  the  upper  hand  under  a  proper 
treatment.  The  following  species  are  generally  included  under 
this  head  : — Aspen  and  other  poplars,  the  sallow  and  other 
willows,  limes,  hazel,  thorns  and  other  shrubs,  sometimes 
also  alder  and  birch,  even  Scots  pine  :  mostly  trees  which 
spring  up  amongst  young  growth,  and  are  removed  in  the 
cleanmgs. 

e.   Fallen  Dead    Wood. 

All  dead  branches    and   twigs    lying   on    the  ground,   and 
refuse  from  fellings  which  the  owner  does  not  require,   are 
p.p.  Q 


82  PROTECTION   AGAINST   MAN. 

generally  included  under  this  heading.  In  some  cases  also 
are  included  dead  branches,  which  can  be  broken  off  by  hand 
from  standing  trees.  In  many  forests,  dead  standing  stems 
up  to  a  certain  girth  are  also  included,  and  stump-wood  as 
well.  The  meaning  of  the  term  fallen  dead  wood  must  there- 
fore be  decided  locally,  but  it  is  rarely  taken  to  include  saleable 
fallen  timber.  This  distinction  is  thoroughl}^  recognised  in 
North-Western  India.  Cutting  tools  must  generally  be  pro- 
hibited, but  a  wooden  rake  may  be  allowed  for  collecting  the 
fallen  dead  wood  on  the  ground.  If  tbere  is  only  a  small 
quantity  of  dead  wood  available  in  a  forest,  the  right-holder 
cannot  claim  other  wood  to  make  up  a  full  supply.  The  sale 
of  such  wood  is  not  usually  permissible,  as  the  servitude  is 
for  household  requirements. 

Within  property  regulated  limits  this  usage  is  only  slightly 
hurtful  to  a  forest,  though  all  dead  wood  eventually  becomes 
humus. 

/.  Lop  and  I'op. 

This  right  is  generally  to  the  crown  of  a  felled  tree  from  the 
place  where  the  stem  is  cut  off  by  the  woodman,  at  a  certain 
fixed  girth,  and  to  the  lower  branches  lopped  off  the  stem. 
The  right-holder  cannot  take  possession  of  the  wood  until 
the  stem  has  been  severed  from  the  crown.  The  only  serious 
disadvantage  caused  by  this  right  to  the  owner  is  that  he 
cannot  well  manage  his  forest  as  Coppice,  or  Coppice-witli- 
Standards,  as  the  greater  part  of  his  produce  would  then  go 
to  the  right-holder. 

If,  however,  the  right-holder  has  the  right  of  lopping  the 
crown  from  standing  trees,  great  injury  will  accrue  to  the 
forest.  In  such  a  case  the  right  must  not  be  exercised  during 
the  growing  season,  and  only  in  compartments  where  the  trees 
are  ripe  for  the  axe,  and  ^t  a  certain  height  from  the  ground. 
A  particular  form  of  this  servitude  is  the  right  existing  in 
certain  forests  to  lop  birch-trees  for  brooms. 

(J.  Slitiujis  and  h'oofs. 

This  right  is  admissible  only  in  High  Forest,  and  the  owner . 
cannot  then  convert  his  forest  into  Coppice,  or  Coppice- with- 
Standards. 


FOREST   RIGHTS.  83 

Unless  it  is  distinctly  laid  down  to  the  contrary,  the  owner 
can  fell  his  trees  as  low  as  he  likes.  The  right  must  be 
suspended  wherever  its  exercise  would  damage  the  forest,  as 
for  instance  in  regeneration-fellings  well  stocked  with  young 
seedlings,  on  steep  slopes  where  landslips  or  erosion  are  to  be 
feared,  or  on  shifting  sands.  Sometimes  the  right-holder  is 
under  the  obligation  to  fill  up  the  holes  made  in  extracting 
the  stumps,  and  to  sow  or  plant-up  the  ground.  The  right 
may  also  be  limited  to  certain  months,  days,  or  hours. 


h.   Wifidfalls  and  Broken  Trees. 

The  right  may  be  to  all  or  merely  to  certain  categories 
of  this  material,  wood  broken  by  wind,  by  snow,  or  rime. 
Trees  which  are  bent  down,  but  may  recover  themselves, 
are  not  included,  nor  are  portions  of  trees  still  rooted 
in  the  ground.  The  right  can  extend  only  to  single  trees 
broken  here  and  there,  not  to  whole  woods  broken  down  and 
uprooted,  as  occasionally  happens  by  an  exceptional  storm  or 
calamity  which  is  not  in  the  contemplation  (naturally)  either 
of  custom  or  a  grant.  The  right-holders  may  use  implements 
to  convert  the  timber.  This  servitude  is  not  of  sylvicultural 
importance. 

i.  Dead  Standing  Trees. 

Poles  and  trees  which  have  died  naturally  are  included  in 
this  class,  and  care  must  be  taken  to  exclude  all  those  which 
may  have  been  killed  intentionally  by  damage,  girdling,  etc. 
This  usage  gives  rise  to  trouble  between  the  right-holder  and 
the  owner,  as  the  latter  will  endeavour  to  remove  dying  trees 
before  they  are  actually  dead,  and  the  former  to  claim  trees 
not  yet  quite  dead.  To  prevent  such  contentions  it  is  better 
to  fix  definitely  the  period  at  which  tbinnings  of  dead  wood 
can  be  commenced. 

As  in  the  former  case,  when  a  large  extent  of  wood  is  killed 
by  injuries  from  storms,  etc.,  the  produce  is  not  the  property 
of  the  right-holder. 

G  2 


84  PROTECTION   AGAINST   MAN. 

2.  Bights  to  Minor  Produce, 
a.  Bark. 

In  Europe  this  right  is  generally  restricted  to  the  bark  of 
trees  yielding  tannin,  sucii  as  oak,  spruce,  larch  and  birch. 

The  bark  can  be  claimed  by  the  right-holders  only  from 
felled  trees  in  regular  fellings.  The  right  may  be  either  by 
quantity  or  by  number  of  trees,  or  commensurate  with  the 
requirements  of  the  right-holder.  The  owner  must  fell  during 
the  growing  season  when  the  bark  can  be  easily  removed. 

Lime-hark,  or  hast,  for  cordage  and  matting  is  sometimes  the 
subject  of  a  right,  and  then  similar  rules  must  be  followed. 
In  India,  *  bark  of  Betula  BJwjjiatra  is  used  for  making 
umbrellas  and  paper,  and  the  bark  of  many  species  of  trees 
for  ropes  and  cords ;  all  these  may  l)e  subject  to  rights. 

b.  Twymtine. 

Eights  to  tap  the  spruce  or  the  Austrian  pine  for  turpentine 
frequently  exist.  The  number  and  size  of  the  trees  to  be 
tapped,  as  well  as  of  the  cuts  to  be  made  in  each,  may  be 
defined,  or  not.  In  any  case  the  usage  must  be  restricted  to 
nearly  mature  woods,  and  there  should  be  a  close-time  between 
successive  tappings  of  the  same  tree,  the  season  during  which 
the  usage  is  permissible  must  also  be  fixed.  As  turpentine  is 
usually  an  article  of  commerce,  it  may  be  in  the  nature  of  the 
right  that  there  is  no  restriction  to  household  requirements, 
nor  as  to  the  sale  of  the  produce. 

This  is  a  most  hurtful  servitude,  as  tapping  for  turpentine, 
especially  in  the  case  of  the  spruce,  results  in  a  loss  of  incre- 
ment, and  lessens  the  quantity  of  timber  in  the  base  of  the 
tree,  and  also  introduces  spores  of  fungi  and  insects  into  the 
wood,  causing  disease. 

c.  Leaves  for  Fodder,  etc. 

This  is  the  right  to  pluck  leaves  from  trees,  especially  for 
feeding  cattle  in  stored  and  simple  coppice.  Implements 
may  not  be  used,  nor  can  twigs  ])e  broken  off.  If  the  demand 
for  leaves  cannot  be  supplied  from  the  regular  fellings,  then 


FOREST    RIGHTS.  86 

certain  compartments  may  be  opened  for  plucking  leaves  as 
far  from  the  ground  as  the  hands  can  reach,  but  only  after 
late  summer. 

In  various  parts  of  India  leaves  of  forest  species  are  used 
for  cattle-fodder,  for  thatching,  for  wrapping  up  goods  at  a 
market,  as  plates,  for  making  umbrellas,  cigarettes,  etc.,  or 
for  manure,  and  sometimes  these  customs  may  have  become 
prescriptive  rights.  In  such  cases  protective  rules  similar  to 
the  above  should  be  enforced. 

Where  foliage  and  branches  are  lopped  for  litter  or  fodder, 
as  in  the  Himalayas  and  in  other  parts  of  India,  where,  owing 
to  the  absence  during  winter  of  fodder  -  crops  or  natural 
herbage,  leaf-fodder  is  wanted,  and  a  prescriptive  right  has 
been  acquired,  it  is  by  custom  limited  to  certain  species,  and 
certain  protective  measures  can  be  adopted.     These  are : — 

(i)  No  lopping  to  take  place  till  after  the  principal  growth 
of  the  year  is  over. 

(ii)  To  restrict  the  usage,  as  much  as  possible,  to  woody 
climbers  and  species  of  little  value  as  timber-trees. 

(iii)  To  forbid  the  lopping  of  the  leading  shoots  of  the 
trees,  and  to  restrict  the  lopping  of  side-shoots  till  tiiey  have 
attained  certain  dimensions  and  only  to  a  certain  height  up 
to  the  stem. 

(iv)  To  give  the  trees  a  rest  so  that  the  same  tree  is  not 
lop[)ed  in  two  consecutive  years. 

(v)  Should  the  right  appl}'  to  more  valiiai)le  timber  trt-es  it 
should  be  restricted  to  compartments  which  will  sliortly  be  cut 
over.  The  use  of  leafy  twigs  and  branches  of  trees  felled  in 
the  ordinary  course  cannot  harm  the  forest. 

(vi)  Where  the  demands  for  this  kind  of  fodder  or  cattle- 
litter  are  large,  and  cannot  otherwise  be  met,  a  regular  system 
of  pollarding  should  be  introduced,  with  a. fixed  rotation  givhig 
the  trees  time  to  recover  between  successive  cuttings.  Such 
a  system  prevailed  in  Epping  Forest  prior  to  1878,  when  the 
right  was  commuted.  The  loppings  of  hornbeam-pollards, 
of  which  this  forest  is  chielly  composed,  were  not,  however, 
used  for  litter  only,  but  also  for  making  fences,  hurdles,  etc., 
and  then  a  rotation  of  ten  years  was  fixed  ;  in  the  former  case, 
the  trees  were  lopped  annually. 


86  PROTECTION   AGAINST   MAN. 

Another  case  in  Western  India  is  the  use  of  green  branches, 
termed  rah,  as  manure  in  rice- fields.  Here  simihxr  rules 
should  be  adopted  as  long  as  this  practice  is  allowed. 

(vii)  In  every  case  where  leaf- fodder  is  used  by  right- 
holders,  the  people  should  be  induced,"  as  far  as  possible,  to 
cut  and  preserve  hay  or  ensilage,  or  to  grow  root-crops  for  the 
winter-fodder  of  their  animals.  Leaf-fodder  from  forests  will 
always  prove  a  valuable  resource  when  other  fodder  fails, 
as  was  the  case  in  France  and  Germany  during  the  drought 
of  1893. 

(I.  Grasa  for  Fodder,  Thatch,  etc. 

Eights  of  cutting  grass  are  also  of  very  common  occurrence 
under  the  coppice  systems,  and  they  should  be  limited  according 
to  locality,  time,  and  mode  of  exercise,  the  limitations  which 
prevail  varying  according  to  local  law  or  custom.  The}^  can 
commence  only  at  a  certain  age  of  the  wood,  and  the  close- 
time  must  be  regulated  according  to  species,  and  to  speciiied 
days,  when  the  forest  guard  can  supervise  the  grass-cutting. 
Sometimes  the  grass  must  be  plucked  by  hand,  or  sickles  or 
scjthes  may  be  used ;  the  latter  instrument  is  evidently  not 
admissible  amongst  young  plants.  If  properly  regulated  and 
supervised,  this  usage  does  little  or  no  harm  on  moist  fertile 
soil,  and  may  even  assist  in  fire-conservancy  by  removing  a 
great  source  of  danger,  and  also  prove  useful  during  the 
reproduction  of  the  forest.  It  is  also  often  usefully  allowed 
as  a  compromise  for  grazing  when  that  cannot  be  allowed, 
and  yet  the  stoppage  is  a  hardship. 


r.  Forest  Pdslurc 

This  right  allows  the  holder  to  graze  his  own  cattle  on  the 
grasses  and  other  herbage  springing  up  in  a  forest  belong- 
ing to  some  other  person.  The  right  to  cut  grass  is  not 
included.  The  forest  owner  has  the  power  of  closing  certain 
areas  in  his  forest,  but  cannot  introduce  changes  of  the  system 
of  management  which  will  prejudice  the  right. 

The  species  and  number  of  grazing  beasts  may  be  defined, 
or  not.     If  the  species  is  not  mentioned,  unimals  such  as  the 


FOREST   RIGHTS.  87 

goat*  and  sheep,  which  are  highly  detrimeTital  to  forest 
growth,  must  he  exchided,  as  in  France  they  are  hy  hiw,  in 
spite  of  any  right  to  the  contrary.  If  the  numher  of  beasts  ia 
Hmited,  sucldings  are  not  counted  in  the  total  number  admitted 
to  graze.  Should  the  number  be  undefined,  as  is  generally  the 
case,  only  so  many  head  should  be  admitted  into  the  forest  as 
can  be  provided  for  without  serious  injury  to  the  forest.! 
Unless  specially  stated,  cattle  intended  for  trade  cannot  share 
in  tliis  right.  The  right-holder  must  engage  a  herdsman  to 
look  after  his  cattle  and  is  responsible  for  his  conduct.  The 
beasts  can  enter  and  leave  the  forest  by  authorised  paths  only. 
The  fencing  of  closed  areas  is  not  obligatory  on  the  forest 
owner,  although  fences  prevent  much  contention  and  further 
his  interests.  The  right  of  grazing  his  own  cattle  in  his  forest 
appertains,  in  every  case,  to  the  forest  owner,  unless  the  con- 
trary is  specially  laid  down  ;  but  he  cannot  graze  them  in 
portions  of  the  forest  that  are  closed  to  the  right-holders' 
cattle. 

/.  Acorns,  Beech- Mas f,  and  Fruits  generally. 

The  kinds  of  fruits  to  be  collected  will  ordinarily  be  specified 
in  the  deeds  regarding  the  right.  The  fallen  fruit  can  be 
picked  up  only  in  compartments  opened  to  the  right,  and  on 
fixed  days  ;  the  riglit-holder  is  held  responsible  for  all  damage 
done  to  the  standing-crop.  Tlucking  the  fruits,  and  the  use 
of  iron  rakes  to  collect  it,  are  forbidden,  and  the  usage  must  be 
limited  to  household  requirements.  Compartments,  the  fruit 
of  which  is  required  for  naturaj  regeneration,  can  be  closed 
against  this  right,  which  does  not  include  the  right  of  pannage. 

These  rights  do  little  or  no  damage  to  the  forest, 

//.   Pannaye. 

This  is  the  right  to  drive  pigs  into  another  person's  forest 
to  feed  ofi"  the  acorns  and  beech  nuts,  etc.,  lying  on  the  ground, 
but  the  right  of  collecting  the  fruit  by  hand  is  not  included. 

An  estimate  of  the  quantity  of  mast  in  any  year  on  whicli 

•  The  possibility  of  prohibiting  yoat.i  in  India  is  discussed  in  "  Forest  Law," 
p.  349/. 

t  See  p.  332  '•  Forest  Law  "  as  to  the  rules  for  fixing  the  number. 


88  PROTECTION   AGAINST   MAN. 

the  number  of *pigs  to  be  admitted  into  a  forest  sbould  be  based 
must  be  prepared  by  an  expert.  The  riglit-holder  can  only 
drive  his  own  pigs  into  tlie  forest,  and  the  forest  owner  has  an 
equal  right.  The  pigs  should  be  withdrawn  when  most  of  the 
acorns  are  eaten,  or  they  will  damage  the  forest.  This  servi- 
tude does  little  harm,  but  is  becoming  rare  in  Europe,  as  stall- 
feeding  of  pigs  is  more  profitable.  Pannage  is  still  practised 
in  the  New  Forest  {ride  p.  31). 

h.  Lifter. 

Litter  to  which  right-holders  are  entitled  may  be  defined  or 
indefinite  in  amount,  and  may  also  be  of  special  kinds  ;  dead 
leaves  and  moss,  weeds,  etc. — in  short,  the  right  to  strip  the 
surface  of  its  covering  down  to  the  soil  may  be  implied. 

An  undefined  right  to  litter  means  the  right  to  take  what  is 
sufficient  for  the  requirements  of  the  right-holder,  and  in  this 
amount,  straw  from  his  own  lands  must  be  reckoned.  Owing 
to  the  prejudicial  nature  of  this  right  on  the  fertility  of  the 
forest,  it  mu^  never  be  stretched  so  far  as  to  include  the 
whole  of  the  litter  a  forest  may  contain. 

The  necessary  limitations  as  regards  localit}',  time  and 
manner  of  exercise  of  the  right  have  been  already  given.* 
Sod-cutting  should  never  be  allowed,  except  from  blanks,  as 
where  trees  are  standing,  the  roots  would  be  exposed  by  this 
practice.  The  exceptional  hurtfulness  of  this  right  to  the  pro- 
ductiveness of  a  forest,  and  the  possibility  that  it  may  lead  to 
its  complete  ruin,  render  it  most  essential  that  the  forest 
should  be  freed  from  it  by  purchase  or  otherwise. 

i.  Quarryiny  or  Uiyyiny  J'i/s  for  Sand,  Uravel,  Turf,  etc. 

Rights  to  stones,  gravel,  sand,  turf,  etc.,  in  another's  forest, 
can  extend  only  to  places  where  the  standing-crop  and  roads 
are  in  no  danger  from  the  right.  Places  for  reception  of  refuse 
from  the  works,  and  export-roads  must  be  designated. 

These  rights,  if  properly  regulated,  can  do  no  injury  worth 
mentioning,  to  the  forest. 

*  Page  49. 


FOREST   RIGHTS.  89 

/.  CoUecting  Berries,  etc. 

The  right  is  always  unlimited  in  amount,  and  cannot  be 
limited,  as  the  produce  is  generally  collected  for  sale.  Except 
in  the  case  of  digging  up  truffles  it  is  quite  harmless  to  the 
forest,  and  need  not  be  interfered  with  beyond  fixing  dates  for 
its  commencement  and  termination  in  any  year. 

TrufHe-hunting,  which  is  carried  on  with  the  help  of  a 
special  breed  of  dogs  resembling  poodles,  must  be  prohibited 
on  the  site  of  fellings,  or  amongst  young  growth. 

k.  Shooting  and  FisJnng. 

The  right  to  kill  game  on  another's  property  has  been 
abolished  by  law  in  Germany.  There,  this  right  is  not  bound 
up  with  the  ownership  of  the  land,  but  is  permitted  only  to  an 
owner  when  his  estate  exceeds  a  certain  area.  It  frequently 
happens,  therefore,  that  the  right  of  shooting  on  a  number  of 
small  estates  is  leased  in  one  lot,  and  the  proceeds  divided  by 
the  owners.  In  England,  the  Crown  possessed  rights  to  the 
game  in  certain  manors,  after  it  had  parted  wirti  the  other 
manorial  rights,  or  actual  ^jroperty  of  the  land,  but  these 
rights  have  now  been  surrendered,  as  in  the  Epi)ing  Forest, 
liaden  Powell*  states  that  in  India  no  prescriptive  rigiits  to 
hunt  in  the  State  forests  have  ever  been  admitted  ;  though 
peoj)le  have  always  killed  game  in  the  forests,  no  right  can  liave 
ordinarily  become  customarg,  for  it  is  not  necessary  to  the 
existence  of  agricultural  villages,  or  communities,  as  is  the 
case  with  grazing  or  wood  rights.  The  question  of  hunting, 
with  rules  for  the  protection  of  game  during  the  breeding 
season  and  when  immature,  is  dealt  with  in  different  countries 
under  special  laws. 

Fishing  rights  t  in  forest  streams  may  exist,  and  are  dealt 
with  by  special  laws  regarding  fisheries.  Tiiese  have  chiefl}' 
reference  to  close-times  during  the  breeding  season  ;  and  to 
protecting  immature  fish  by  fixing  a  minimum-sized  mesh 
where  nets  are  allowed ;  also  to  prohibiting  tlie  poisoning  of 
streams,  and  other  unsportsmanlike  ways  of  catching  fish. 

•  "  Forest  Law,"  pp.  338.  364. 

+  Ref^ulations  for  the  protection  of  game  and  fish  in  the  State  forests  of  India 
have  been  framed  by  the  Local  Governments  of  the  different  Provinces. 


90  PROTECTION   AGAINST   MAJf. 

3.  Siuidri/  Ilifihts  (Easements), 
a.  Rujlifa-of-Way. 

Rights-of-way  if  too  numerous  in  a  forest  may  tend  to 
hamper  the  management,  especially  by  causing  danger  from 
fire,  and  increasing  the  cost  of  fire-protection.  It  is  therefore 
important  to  prevent  new  rights-of-way  from  arising  by  pre- 
scription, and  where  the  law  permits,  to  close  altogether  roads 
or  paths  which  may  liave  gone  out  of  use,  or  others  for  which 
a  more  convenient  substitute  may  be  found.  These  rights 
may  be  subdivided  into  rights  io  footpatlis,  cart-roads  {the  x\g\\\, 
of  removing  timl)er  over  the  land  of  a  third  party),  or  drift-roads 
(for  the  passage  of  cattle),*  the  second  category  sometimes 
including  the  third. 

In  all  these  cases  the  question  arises  as  to  the  legal  breadth 
of  the  way,  and  whenever  this  is  uncertain,  it  should  be  deter- 
mined with  reference  to  the  breadth  of  the  way  required  by 
the  circumstances  of  the  case,  and  according  to  local  custom. 
Tlie  right  of  removing  timber  over  another's  land  can  be 
exercised  only  when  the  crops  on  that  land  would  not  be 
prejudiced  by  so  doing,  i.e.  w'hen  the  land  is  fallow,  or  when 
frozen,  during  winter.  The  right-holder  whose  cattle  pass 
along  a  road  to  pasture,  is  responsible  for  any  damage  done 
to  the  forest  growth  beyond  the  limits  of  the  road ;  and  the 
owner  of  the  forest,  according  to  circumstances,  may  or  may 
not  be  compelled  to  protect  his  forest  by  ditches,  fences,  or 
hedges. 

/>.  Riiihls  la    Wafer. 

Plights  to  water  generally  refer  to  the  servient  estate 
receiving  the  drainage  water  for  a  dominant  estate,  or  allowing 
(not  obstructing)  the  flow  of  (useful)  water  from  the  servient  to 
the  dominant.  Sometimes  it  includes  allowing  a  canal-cut,  or 
irrigation  channel  being  taken  across  the  servient  estate,  in 
which  case  the  maintenance  of  the  water-channel  is  the 
business  of  the  right-holder.  Rights  to  use  springs  or  wells 
in  another  person's  forest,  or  to  water  cattle  at  them,  all  of 
which  involve  rights-of-way  through  the  forest  to  the  source 
of  the  water,  are  also  included. 

•  See  "  Forest  Law,"  ji.  'Alh  ff. 


FOREST   RIGHTS. 
c.  Right  to  float  Timtm: 


91 


The  kinds  of  timber  to  be  floated  should  be  specified  and 
the  owner  of  the  stream  has  the  same  rights  as  the  right- 
holders.  The  right  of  footpath  along  the  bank  of  the  stream 
may  be  also  combined  with  this  riglit,  the  breadth  of  the  path 
being  determined  by  custom.  In  India,  this  right  is  alwaj^s 
exerciseable  under  the  control  of  the  State  only. 

d.  Rights  of  burning  Charcoal,  sfacJcing  Wood,  etc. 

The  sites  where  the  charcoal  is  to  be  burned  or  the  wood 
stacked,  must  be  pointed  out  to  the  right-holder,  and  also  the 
roads  to  be  used  for  export,  which  should  be  as  convenient  as 
circumstances  will  allow.  AVherever  charcoal  is  burned,  special 
precautions  must  be  taken  against  danger  to  the  forest  from 
fire. 


PAKT  II. 

PROTECTION   AGAINST   ANIMALS. 


95 


PEOTECTION   AGAINST   ANIMALS. 

INTRODUCTORY   REMARKS. 

The  question  of  the  usefulness  or  hurtf ulness  of  wild  animals 
indigen(Mis  in  Europe  may  be  considered  from  a  forest,  sporting, 
or  agricultural  point  of  view.  Under  Forest  Protection  only 
the  forest  point  of  view  will  be  considered,  but  even  under  this 
heading  some  difficulty  will  l)e  experienced,  for  the  following 
reasons*  :— 

1.  A  number  of  animals  are  at  tlie  same  time  both  useful 
and  injurious  to  forests. 

2.  The  degree  of  utility  or  harm  done  by  one  and  the  same 
animal  differs  according  to  its  age,  to  local  circumstances 
(season  of  the  year,  condition  of  the  woods,  etc.),  so  that  it 
is  hardly  possible  to  lay  down  definitely  that  certain"animals 
are  absolutely  injurious,  or  useful.  Thus,  the  fox,  though  a 
great  enemy  to  barn-door  fowls  and  game,  may  be  very  useful, 
especially  in  a  broadleaved  forest,  which  suffers  more  than 
coniferous  woods  from  rodents.  Thrushes  and  blackbirds  in 
spring  and  summer  feed  mainly  on  worms  and  insects,  but  in 
autumn  chiefly  on  berries.  The  cuckoo  and  bats  are  always 
useful,  while  bark-beetles,  the  Nun-moth  and  other  insects  are 
absolutely  injurious  to  forests. 

3.  The  utility  of  certain  animals  to  forests  may  be  direct, 
or  iudirect.     Thus  the  jay  may  be  directly  useful  by  carrying 

•  Intentional  introduction  of  exotic  animals  to  coniViat  insect  pests  have  not 
always  proved  advantageous.  Thus,  European  sparrows  were  introduced  into 
the  N.-K.  States  of  America  in  18rj0  and  1867  to  destroy  canker-worms.  The 
sparrows  are  now  an  unmitigated  pest  throughout  N.  America,  while  the  canker 
worm  has  been  replaced  hy  a  worse  insect,  which  the  sparrows  never  touch. 
Similarly  the  mongoose  was  introduced  into  Jamaica  in  1872  to  destroy  the  cane- 
piece  rat.  This  it  did  in  ten  years,  but  since  then  it  has  proved  most  destructive 
to  ground-nesting  birds,  to  insectivorous  reptiles  and  batrachia,  as  well  as  to  fruits 
and  vegetables,  so  that  the  mongoose  does  much  more  damage  than  the  rat.  On 
the  other  hand  the  Australian  ladybird  (Vedtilia  cardinalig)  introduced  into 
California  in  1889,  has  saved  the  citrus-growing  industry  from  the  cottony 
cushion  scale,  Icarya  purchasi. 


96  PROTECTION    AOAINST   ANIMALS. 

about  acorns,  and  dropping  them  in  the  forest,  while  certain 
mammals  and  many  birds  and  insects  are  indirectly  useful 
by  destroying  injurious  mice  or  insects. 

4,  The  injury  done  may  also  be  direct  or  indirect;  the 
former  consisting  in  damage  or  destruction  to  forest  produce, 
the  latter  in  killing  useful  species.  Most  destructive  kinds 
of  animals  are  either  mammals  or  insects,  while  birds  are 
generall}^  useful. 

5.  The  amount  of  damage  done  to  the  forest  depends  on 
the  species  causing  it,  the  local  conditions,  the  season,  etc. 
It  is  generally  in  inverse  proportion  to  the  size  of  the  animal; 
the  little  bark- beetle,  on  account  of  its  rapid  increase  and 
steady  working,  doing  more  damage  to  a  forest  than  the  large 
red-deer.  The  woodpecker  is  a  good  instance  of  the  difficulties 
of  deciding  as  to  the  amount  of  harm  or  good  done  to  a  forest 
by  a  particular  species.  This  bird  is  useful,  in  destroying 
numerous  insects  living  in  wood,  but  it  sometimes  damages 
healthy  trees  by  boring  holes  into  them,  while  these  holes 
may  be  aseful  if  subsequently  occupied  by  bats  or  starlings, 
but  injurious  if  occupied  by  stock-doves. 

Protective  measures  in  the  case  of  animals  may  be  either 

preventive  or  remedial,  and  will  be  dealt  with  under  the  following 

heads  : — 

,r  1       rDeer  and  wild  pigs. 

Mammals    l^    ^     . 
lEodents. 

Birds. 

Insects. 

As  already  stated,  the  present  work  can  deal  in  detail  only 
with  European  animals,  but  it  may  be  mentioned,  that  in 
India,  the  Nilgai  {Portax  ;)/cf»s)  and  the  common  antelope 
{Antilope  hezoartica)  do  much  damage  in  coppices  and  plan- 
tations adjoining  agricultural  land ;  whilst  among  birds,  the 
pheasants  and  jungle-fowls  do  similar  damage  to  that  by  grouse 
in  Europe.  For  a  fuller  account  and  especially  of  Indian  forest 
insects  the  reader  is  referred  to  "Indian  Forest  Zoology,"* 
by  E.  C.  Cotes,  also  "  Injurious  Insects  in  Indian  Forests,"* 
and  other  works  by  E.  P.  Stebbing. 

*  Published  Vjy  the  Superintendent  of  Government  Printing,  Calcutta,  1893. 


97 


CHAPTER   I. 

PROTECTION    AGAINST    DEER    AND    WILD    PIGS. 

Skction  I. — General  Account. 
1.  List  (if  Injurious  Species. 

Red-deer  {Cercus  claplnis,  L.). 
Fallow-deer  (Damns  vah/aris,  Brook). 
Roe-deer  (Cernis  capreolus,  L.). 
Wild  pig  (Siis  scrofa,  L.). 

2.  Damcuje  Done. 

The  above-named  animals  injure  the  forest  by  eating  the 
fruit  of  trees,  biting-off  buds  and  young  shoots,  trampling- 
down  seedings,  breaking-off  leaders,  bending-down  stems, 
barking  poles,  exposing  and  gnawing  roots.  Further  details 
regarding  the  damage  will  be  given  under  the  headings  of 
each  species. 

The  consequences  of  the  damage  done  consist  in  loss  of 
increment,  stunted  growth,  diminution  of  timber  as  compared 
with  firewood,  increased  danger  from  insects,  fungi,  storms, 
snow,  etc.  Hess  considers  it  advisable  to  keep  down  the 
beasts  by  the  eti'orts  of  the  Forest  Staff,  and  not  to  lease  the 
shooting  in  forests,  as  this  usuall}'  leads  to  inordinate 
numbers  of  deer,  etc.,  and  to  great  injury  of  the  growing 
woods. 

3.  Preventive  Measures. 

The  chief  preventive  measures  are : — 

(a)  Formation  in  High  Forest  of  large,  connected  regenera- 
tion-areas ;  small  clearings  in  which  game  has  not  sufficient 
room,  and  strip-fellings  near  thickets  or  poles  where  the  game 
habitually  remains,  suffer  most  of  all.  For  sylvicultural  reasons, 
however,  very  large  felling-areas  are  not  permissible.    Periods 

F.P.  H 


98  PROTECTION    AGAINST   ANIMALS. 

of  regeneration  must  be  long  and  cleanings  of  inferior  species 
delayed,  until  the  shelter  they  afford  to  the  better  kinds  of 
plants  is  no  longer  required. 

{b)  Covering  endangered  fruits,  acorns,  etc.,  in  seeding- 
fellings. 

(c)  Avoidance  when  possi])le  of  autumn-sowings,  and  pre- 
ference of  planting  to  sowing,  the  former  with  large  and 
strong  transplants.  More  plants  per  acre  must  be  planted 
than  where  damage  is  not  feared. 

(d)  Avoidance  of  the  introduction  of  species  specially  liked 
by  the  game. 

(e)  Careful  choice  of  system  and  great  care  in  the  manage- 
ment of  forests  containing  game. 

(/)  Care  for  the  nourishment  of  the  game  by : — 

Introduction  of  mast-producing  species,  oaks,  chestnuts,  etc., 
wherever  the  locality  is  suitable  for  them. 

Protection  of  softwoods  (aspen,  willows,  etc.)  in  cuttings 
frequented  by  game,  and  introduction  of  these  if  necessary. 

Cultivation  of  fodder-crops  for  the  game.  Oats,  buckwlieat, 
turnips,  potatoes,  Jerusalem  artichokes,  clover,  etc.,  according 
to  the  species  of  game  which  is  prevalent. 

Encouragement  of  a  growth  of  grass  in  the  forest;  stopping 
grass-cutting  and  pasture. 

Feeding  the  game  in  the  deptli  of  winter,  and  when  there  is 
much  snow  on  the  ground.  Loppings  of  aspen,  willows,  limes, 
or  other  softwoods,  form  suitable  food  in  winter.  The  animals 
peel  the  bark  from  these  loppings,  and  eat  the  buds  and  young 
shoots.  Hay,  unthrashed  oat-straw,  oats,  maize,  potatoes,  etc., 
may  be  given  and  l)asic  slag  added  to  improve  the  horns  of 
the  stags.  About  one-thirtieth  by  weight  of  basic  slag  may 
be  added  to  the  fodder.  The  fodder  should  be  placed  in 
the  older  woods  near  water,  and  well  distributed,  so  that  several 
beasts  can  feed  at  once.  In  mountain  forests,  places  sheltered 
from  the  wind  and  southerly  aspects  should  be  selected  as 
feeding-places,  as  deer  assemble  in  such  places  during  winter. 

4.  Remedial  Measures. 

(a)  Substantial  fencing  of  forest  nurseries  and  cultivations, 
or  of  the  game-preserve.     The  kind  and  heiglit  of  the  fence 


RED-DEER.  99 

to  be  used  depends  on  the  mode  of  life  and  size  of  the  game. 
The  fences  must  always  be  kept  in  good  order.  Digging  a 
ditch  outside  the  fence  will  afford  additional  security. 

(b)  Specially  valuable  trees  should  be  separately  fenced-in, 
or  protected  by  rough  stakes  with  the  jagged  ends  of  brandies 
outside.  Thorns,  bad-smelling  substances,  or  wire-netting 
may  also  be  used. 

(c)  Scarecrows  may  be  set-up  in  endangered  localities,  or 
dogs  brought-in,  blank-cartridges  fired,  etc.  The  scarecrows 
must  be  altered  from  time  to  time,  as  the  animals  get 
accustomed  to  them. 

{d)  Shooting-down  the  game  to  a  restricted  number  which 
the  forest  can  bear.  Game  need  not  be  exterminated,  and  the 
chief  difference  between  modern  and  old  times  consists  in  the 
fact  that  formerly  the  forest  was  managed  for  the  game,  but 
now  it  is  recognised  that  the  admissible  quantity  of  game 
must  be  proportioned  to  the  niterests  of  the  forest. 

Section  II. — Red-Deer. 

1.  Damage  Done. 

The  damage  done  by  red-deer  consists  in  eating  fruits, 
browsing,  peeling,  rubbing,  trampling,  etc. 

ff.  Enfitif/  Forest  Fruits. 

The  red-deer  eats  all  kinds  of  fruits,  but  especially  acorns, 
beech-nuts,  chestnuts,  mountain-ash  berries,  etc.  Acorns  are 
often  beaten-out  by  the  deer  with  their  fore-feet  and  eaten, 
and  sow'ings  may  be  thus  completely  ruined. 

I>.  Browsinij. 

The  deer  bite-off  buds  and  young  shoots,  chiefly  from  late 
autumn  till  spring,  and  occasionally  devour  foliage  in  the 
summer. 

The  following  species  are  preferred  by  red-deer :  aspen, 
sallow,  ash,  oak,  hornbeam,  beech,*  '  maple,  hazel,  and 
amongst  conifers    the  silver-fir  and  larch;  the  birch,    alder, 

•   In  the  Ardennes,  re<l-deer  apparently  leave  beech  alone. 

H    2 


100  PROTECTION    AGAINST    ANIMALS. 

Scots  pine,  and  spruce  are  least  liked,  but  different  circum- 
stances, such  as  a  mixture  of  species,  system  of  management, 
growth  of  grass  or  supply  of  fodder,  greatly  inthience  the 
degree  of  damage  done  in  any  particular  case.  Deer  and 
cattle  are  fond  of  tasting  new  and  foreign  species  introduced 
into  a  wood. 

In  times  of  scarcity  of  fodder,  young  plants  protruding 
through  the  snow  may  be  completely  browsed-down ;  in 
mound-planting  this  is  especially  noticeable. 

Overshadowed  plants  are  less  freely  browsed  when  compared 
w'ith  those  growing  in  the  open.  Old  stags  and  hinds  do  more 
damage  than  fawns,  as  they  can  reach  higher.  Southern  and 
western  aspects  suffer  more  than  northern  and  eastern  ones, 
as  the  deer  frequent  the  former  in  the  winter.  The  lower 
parts  of  the  warm  aspects  bordering  on  fields  suffer  most,  as 
during  winter  the  deer  crowd  together  into  such  places.  Here 
may  be  found  those  rounded,  bush  like  plants  due  to  the 
annual  formation  of  numerous  side-shoots,  exposed  every 
year  to  the  bite  of  the  deer.  The  young  plants  also  suffer 
much  in  frost  localities,  on  account  of  their  slow  growth.  Of 
great  influence  on  the  amount  of  damage  done  are  the  degrees 
of  recovery  shown  by  certain  species,  due  to  power  of  repro- 
duction, rapid  growth,  and  also  to  local  circumstances.  Beech 
and  hornbeam  recover  well  from  browsing,  although  the  former 
does  not  reproduce  well  from  the  stool.  Oak  when  bitten  also 
shows  great  power  of  recover}',  the  ash  and  maples  less,  also 
conifers,  among  which  the  silver-fir  has  the  best  power  of 
recovery.  The  bite  is,  however,  never  clean,  the  deer  having 
no  lower  incisors,  so  that  recovery  is  difficult,  01)viously, 
quick-growing  trees  on  a  rich  soil,  make  the  best  recovery. 

c.   Poclinij  Bark. 

A  bad  kind  of  damage  done  by  red-deer  consists  in  peeling 
the  bark  of  trees,  which  is  generally,  but  not  always,  eaten. 
Peeling  is  commoner  in  woodlands  with  a  large  stock  of  deer, 
that  are  fenced-in  from  the  adjoining  fields.  The  whole  herd 
is  probably  taught  to  peel  by  one  or  two  stags  or  old  hinds. 
In  open  forests  peeling  is  rarel}'  practised. 


RED-DEER. 


101 


The  following  species  are  thus  attacked  : — 
Chiefly  spruce  and  oak. 

Less,  the  ash,  silver-tir,  beech,  hornbeam,  maple,  hazel. 
Least  of  all,  Scots  and  black  piues,  larch,  alder,  and  birch. 


(Reduced.) 
Fig.     22.— Oak     sapling, 
18 — 20  years  old,  peeled 
bv  red-deer. 


{liediict'd.) 
Fig.  23.— Summer- 


Fig.  24. — Winter-peeling 
ou  40  —  50-year-old 
spruce. 


Spruce,  from  20  to  40  years  old,  and  15  to  20-year-old  oak 
coppice-shoots  are  preferred,  but  spruce  up  to  60  years  old  are 
also  attacked.  In  the  case  of  Scots  pine,  after  20  years  the 
bark  becomes  too  thick  to  be  injured.  Well-thinned  compart- 
ments are  preferred,  as  the  deer  can  get  about  better  in  them, 


102 


PROTECTION     AGAINST     ANIMALS. 


and  prefer  a  sappy  bark  developed  in  the  light.  The  stag 
does  the  most  damage  in  this  way.  The  hark  may  be  removed 
from  all  round  the  stem,  or  in  strips.  The  former  is  much 
more  hurtful,  hut  is  rare.  Strip-peeling  may  be  done  on  both 
sides  of  stems,  but  usually  in  spruce  only  on  one  side,  the 
west  and  east  sides  being  preferred.  In  the  case  of  the  oak 
and  beech,  the  bark  is  often  stripped-oflf  in  patches  one  above 
the  other,  as  shown  in  Fig.  22. 

The  bark  may  be  peeled  in  winter  or  summer,  in  the  former 
case  from  absolute  hunger.     In  the  latter  case,  the  deer  bite 


Fijr.  2o.— Transver 


1  in  suiumer  (reduced). 


through  the  strip  of  bark  from  below,  hold  it  witli  their  teeth, 
and  then,  walking  backwards,  and  raising  the  head,  strip  it  off 
in  long  pieces,  which  cause  serious  wounds  in  the  tree.  Their 
length  may  be  6  feet,  and  breadth  from  2  to  6  inches,  and 
they  may  reach  down  to  the  roots,  but  generally  stop  at  about 
2  feet  above  them. 

Winter-peeling  is  generally  less  serious,  the  deer  gnawing 
off  and  eating  pieces  of  the  outer  bark,  leaving  the  bast  and 
part  of  the  bark  between  the  bared  strips.  When  deep  snow 
is  on  the  ground  these  wounds  may  be  pretty  high  up  the 
stem. 

Peeling  is  generally  done  in  the  morning  after  the  deer  have 
eaten  a  meal,  and  after  rain,  which  softens  the  bark. 


RED-DEER. 


103 


The  disastrous  consequences  of  peeling  consist  in  loss  of 
increment  and  the  formation  of    badly-shaped  boles  by  the 


Fig.  26. — Longitudinal  section  of  an  oak-stem  peeled  from  a  to  b,  and  occluded. 
{Nat.  size.) 


Fig.  27. — Transverse  section  of  -anie  oak.     c.  Injured  spot. 

bulging-out  of  the  annual  rings  of  wood,  which  may  render 
the  trees  lop-sided,  as  shown  in  Fig.  25. 


104  I'KOTECTION    AOAIN.ST    ANIMALS. 

Occasionally  peeling  gives  rise  to  the  formation  of  ad- 
ventitious buds  from  below  the  wound,  and  frequently  to 
decay,  such  as  red-rot  in  spruce,  or  Peziza  Willkommii  in  larch. 
The  stems  which  have  been  attacked  become  unserviceable 
except  for  fuel,  and  the  tree  often  gets  broken  by  wind  or  snow 
at  or  just  above  its  injured  portion.  Insects,  such  as  bark- 
beetles  and  wood-wasps,  frequently  attack  the  tree,  which  will 
die  if  completely  girdled. 

Such  injuries  to  broadleaved  species  are  soonest  healed  in 
the  case  of  the  oak.  In  favourable  cases  only  little  damage  may 
be  done,  leaving  small  local  traces  of  decay  (Figs.  26  and  27). 

The  newly-formed  rings  of  wood,  however,  never  completely 
repair   the   damage   when   the   sapw'ood   has    been    exposed. 


Fig.  28. — Transverse  section  of  a  60 — 80-year-old  spruce,  which  lias  been 
occluded  after  being  peeled  by  red-deer. 

though  they  may  occlude  it.  Wounds  of  the  ash  also  recover 
rapidly,  although  the  wood  of  this  si)eci€'s  is  easily  injured. 
Beech  and  hornbeam  recover  with  greater  difficulty,  and  the 
maple  more  slowly  still. 

Amongst  conifers  the  following'  scale  is  in  descending  order 
of  power  of  recovery  : — 

Silver-fir,  larch,  Weymouth  and  Scots  pines,  spruce.  Such 
a  thorough  recovery  as  is  shown  in  Fig.  28  is  very  rare. 


RED-DEER. 


105 


The  gravity  of  the 
damage  done  depends,  in 
other  respects,  on  the  size 
of  the  wounds,  the  season, 
repetition  of  the  injury  to 
the  same  tree,  age  of  the 
wood,  and  nature  of 
locaHty.  Summer -peehng 
is  more  injurious  than 
winter-peehng,  although  in 
the  former  case  the  anti- 
septic nature  of  the  outflow 
of  turpentine  is  to  some 
extent  a  compensation. 

At  the  commencement  of 
spring  most  damage  is  done 
in  this  way.  The  younger 
the  wood,  the  more  fertile 
and  moister  the  soil,  the 
quicker  the  damage  is 
repaired. 

Bark-peeling  by  red-deer 
is  a  new  habit ;  as  long  as 
mixed  woods  under  the 
Selection  system  and  cop- 
pice-with-standards  offered 
plenty  of  nourishment,  the 
deer  left  the  bark  alone, 
but  the  present  density  of 
growth,  which  excludes 
grass,  and  the  substitution 
of  conifers  for  broadleaved 
species,  have  rendered 
fodder  scarce  in  the  forests, 
and  it  is  possible  that  the 
deer  eat  the  bark  medicin- 
ally, as  well  as  from 
hunger,  and  also  partly 
from  sportiveness. 


Fig.  29.- 


-Spruce  .saplings  rubbed 
by  red-deer. 


106  PROTECTION   AGAINST    ANIMALS. 

d,  Ruhhini/  (tnd  Striking. 

The  stags  rub  their  antlers  against  trees  to  remove  the 
velvet  at  the  end  of  July  and  August,  generally  by  night,  and 
they  select  for  the  purpose  slender  smooth  poles  of  lime, 
aspen,  sallow,  larch,  Wey mouth-pine,  silver-fir,  maple,  etc., 
especially  when  these  species  are  scattered  among  other  forest 
growth.  Scots  pine  poles  are  also  injured  in  this  way  by 
deer  in  the  Ardennes. 

Stags  also  strike  their  antlers  against  trees  at  rutting- time 
in  September  and  October,  and  before  they  lose  them  in 
March  and  April.  The  damage  done  in  this  way  is  less  than 
by  peeling,  as  the  same  trees  serve  over  and  over  again  for 
the  purpose.  It  can  readily  be  distinguished  from  peeling  by 
the  filaments  of  bark  which  occur  on  the  wound,  and  by  the 
hairs  of  the  deer  adhering  to  it,  from  the  deer's  habit  of 
rubbing  its  neck  on  the  peeled  stem. 

e.   Tramiiliiuj. 

Damage  done  l)y  trampling  is  confined  to  young  growth  and 
sowings  of  conifers  ;  1-  and  2-year-old  plants  on  steep  slopes 
with  loose  soil  suffer  most  of  all,  being  frequently  uprooted. 

/.   Tokd  Amount  of  Dinmiyp. 

More  experience  is  required  regarding  the  total  amount  of 
damage  done  to  forests  by  red-deer.  A  forester  who  is  at  the 
same  time  a  sportsman,  should  endeavour  to  ascertain  clearly 
the  amount  of  sacrifice  of  income  his  sport  involves,  so  that 
he  may  be  able  to  keep  the  number  of  deer  within  proper 
limits.  Until  the  damage  done  under  certain  circumstances 
has  been  properly  observed,  sympathy  with  sport,  or  antipathy 
to  it,  give  the  question  a  wide  range.  It  may  not  be  possible 
to  estimate  the  proportional  amount  of  damage  done  respec- 
tively by  browsing,  peeling,  trampling,  etc.,  but  in  a  forest 
frequented  by  deer,  certain  compartments  might  be  fenced  and 
others  left  open,  and  comparative  yield-figures  ascertained, 
from  which  the  extent  of  the  damage  done,  in  the  latter  case, 
may  be  deduced. 

As  regards  the  damage  to  meadows  adjoining  forests  that 


RED-DEER.  107 

contain  red-deer,  Ihrig  states  that  in  the  Odenwald,  at 
Eulbaeh,  31  per  cent,  of  the  normal  yield  of  hay  is  lost 
annually  by  the  grazing  of  red-deer,  the  loss  being  estimated 
at  6  cwt.  per  acre,  or  3^  cwt.  per  head  of  deer,  worth  2is. 
(F.  u.  J.  Zeitung,  1890,  p.  451).  The  Exmoor  deer  feed 
chiefly  on  the  adjoining  farm-crops,  the  damage  they  do  being 
very  considerable. 

2,  Protective  Measures. 

Besides  the  general  rules  given  above  (p.  84),  the  following 
special  rules  relate  to  red-deer : — 

a.  Maintenance  of  a  Moderate  Number  of  Deer. 

A  sufficient  number  of  deer  must  be  killed  annually  so  that 
the  stock  in  a  forest  is  not  incompatible  with  economic 
forestry. 

As  the  term  moderate  varies  with  the  species  of  tree  grown, 
tlic  system  of  management,  locality,  nature  of  boundaries  and 
grass-production,  it  is  impossible  to  give  good  average  figures. 

According  to  G.  L.  Hartig,  on  2,500  acres  of  forest  the 
stock  of  deer  in  the  spring,  before  the  young  are  born  (May  to 
June)  may  be  as  follows  : — 


Broads 

leaved 

Forest. 

Co/iifercms  .Forest. 

Red-deer. 

Iioe.% 

,      Wild 

Eed-deer.     Roes.       Wild, 

Forests    boiileiing    ou    other 

Piffs. 

Pigs. 

forosls         .... 

8     .. 

.     8 

...     4 

12     ...     16     ...     4 

Forests  bordering  on  fiehls 

4     .. 

.     8 

— 

4     ...     10     ...    — 

Forests  surrounded  by  fields  . 

2     .. 

.  .8 

...    — 

2     ...     12     ...    — 

liatzeburg  considers  16  red-deer  per  2,500  acres  the  proper 
number.  In  Compiegne  forest,  20  deer  for  2,500  acres  are 
allowed. 

Prince  Charles  of  Schwartzenburg  states  that  in  Bohenjia 
15  to  35  head  of  red-deer  are  admissible,  and  places  one  red- 
deer  as  equal  to  two  fallow-deer  or  four  roe-deer.  Von 
Dombrowski  allows  40  head.  These  figures  approach  those 
for  a  forest  overstocked  with  deer.  Unforluiiately  as  many  as 
one  head  per  25  to  40  acres  of  woodland  occur  in  many  forests 
in  Thuringia,  the  Harz  and  Taunus,  so  that  economic  forestry 
becomes  impossible. 


108  PROTECTION    AGAINST    ANIMALS. 

h.  Sufficient  Fodder  must  tie  Si/jt/died  to  tJie  Deer  in    Winter. 

Oats,  turnips,  acorns  and  chestnuts  are  best.  Basic  slag 
should  be  mixed  with  the  food,  as  already  stated  (page  98). 
Feeding  only  with  hay  or  leaf-fodder  causes  the  deer  to  fall-off 
in  health,  and  prevents  the  formation  of  good  antlers,  whilst 
acorns  are  best  for  the  latter.  The  fodder  should  not  be  given 
on  felling-areas,  nor  near  recent  thinnings,  as  the  deer  loiter 
about  near  the  feeding-places  and  cause  damage.  Owing  to 
the  scarcity  of  food,  antlers  in  the  Highlands  of  Scotland  are 
very  poor  when  compared  with  Continental  antlers,  or  those 
from  English  parks,  or  from  Exmoor. 

r.  Fences  against  Bed-Deer. 

These  should  not  be  less  than  7  feet  in  height,  and  on  slopes 
another  foot  may  be  added  to  prevent  the  deer  from  leaping 

the  fences. 

d.  To  Prevent  JJrotvsinf/. 

Young  forest  growth  may  be  sprinkled  with  blood  and  cow- 
dung,  or  open  jars  full  of  blood  buried  in  the  ground.  Coal- 
tar  may  be  lightly  painted  on  strong  young  conifers,  excepting 
the  buds.  It  is  best  done  by  passing  the  shoots  lightly 
through  the  hand  covered  by  a  tarred  glove.  This  should  be 
done  from  September  till  Noveml)er,  and  repeated  when 
necessary.  The  spruce  stands  this  treatment  less  well  than 
the  Scots  pine,  and  broadleaved  species  suffer  from  the 
practice.  The  cost  is  not  high,- about  2s.  (W.  an  acre,  including 
the  purchase  of  6  lbs.  of  tar.  A  woman  can  tar  300  plants  in 
an  hour. 

Broadleaved  species  may  be  daul)ed  with  the  following 
mixture  : — 

Carriage  grease  .         .         .5  lbs. 

Petroleum  .         .         .         .2^  quarts. 

Alum  .         .         .         .       f  lb. 

Tallow         .         .         .         .fib. 

This  gives  enough  for  COO  plants.  Plants  may  also  be  limed, 
the  terminal  buds  being  smeared  with  a  brush  dipped  in 
whitewash.     This  costs  for  silver-lir  Is.  6d.  per  1,000  plants. 


FALLOW-DEER.  109 

or  2s.  4d.  an  acre;  10  lbs.  of  lime  are  required  for  1,000 
plants.  A  woman  can  lime  about  500  plants  in  a  day  on  a 
slope,  and  3,000  plants  on  level  ground.  This  gives  better 
results  than  tarring  the  plants,  and  the  lime  apparently  does 
them  no  injury.  Eefuse  hemp  may  also  be  lightly  placed 
over  plants,  as  it  clogs  the  teeth  of  the  deer  and  has  proved 
efficacious. 

e.  Jfmsures  to  Prevenf  Peeling. 

Delay  thinnings,  so  that  deer  cannot  penetrate  amongst 
saplings. 

Pieces  of  rock-salt  should  be  scattered  about  for  the  stags  to 
lick,  or  the  following  composition  : — 

Oak-galls       .         .         .         .  1  lb. 

Salt 1  lb. 

Clay 8  lbs. 

Anise A  little. 

The  galls  should  be  Istrian,  which  cost  50.s.  a  cwt.  Each 
piece  suffices  for  100  acres  of  forest. 

Beasts  detected  peeling  bark  should  be  shot,  as  young  deer 
soon  follow  their  example. 

/.  Measures  to  Prevent  Rublriivj,  etc. 

Valuable  exotics,  etc.,  can  be  protected  against  rubbing  by 
smearing  them  with  certain  compositions  up  to  5  feet  in 
height. 

Such  a  composition  is  a  mixture  of  lime,  blood  and  sulphur. 

Section  III. — Fallow-Deer. 

The  damage  done  by  the  fallow-deer  is  of  a  similar  nature  to 
that  by  the  red-deer  ;  the  former  perhaps  does  more  harm  by 
bruising  and  trampling,  as  it  is  very  restless,  and  particular 
about  its  food.  However,  it  never  peels  in  a  wild  state,  only 
sometimes  in  fenced  parks.  The  fallow-deer  rubs  its  antlers 
at  the  end  of  August  and  in  September,  and  strikes  the  same 
species  as  the  red-deer.  The  protective  rules  are  the  same, 
except  that  precautions  against  peeling  are  unnecessary. 


110  PROTECTION    AGAINST    ANIMALS. 

Section  IV. — Roe-Deee. 
1.  Damage  Done. 

Besides  herbage,  the  roe  eats  beech-mast,  acorns,  wild  fruit, 
and  the  cotyledons  of  beech  and  oak  seedlings,  and  in  winter 
browses  on  the  buds  and  shoots  of  nearly  every  species  of 
tree,  especially  young  plants,  and  in  summer  on  fresh  young 
shoots  and  tender  foliage. 

The  following  species  are  preferred  : — Oak,  beech,  maple, 
ash,  elm,  hornbeam,  aspen,  sallow  and  silver-fir;  less — Scots 
and  Weymouth  pines  and  spruce  ;  least  of  all — birch  and 
alder.  Young  plants  one  or  two  years  old  may  be  entirely 
devoured.  Exotic  species  and  those  occurring  rarely  in  a 
wood  are  preferred. 

Sunny  aspects  where  the  roe  stays  in  winter  suffer  most, 
especially  on  poor  soils.  The  roe  rubs  its  horns  in  March  and 
April  on  smooth-barked  saplings  about  a  finger's  thickness, 
and  strikes  its  horns  on  poles  in  rutting-time  at  the  end  of 
July  and  August,  and  before  losing  them  in  November.  Larch, 
Weymouth-pine,  Douglas-fir,  aspen,  lime,  and  mountain-ash 
are  most  exposed  to  these  injuries. 

In  places  where  roe-deer  crowd  together,  they  trample-down 
many  seedlings.  The  roe  is  relatively  worse  as  a  forest 
browser  than  the  red-deer,  as  it  is  very  dainty  and  tears  the 
shoots  like  a  goat ;  but  on  account  of  its  small  size,  and  as  it 
abstains  from  peeling  trees,  it  does  a  less  absolute  amount  of 
damage. 

2.  Protective  Rules. 

Irrespective  of  the  general  rules  given,  the  following  hold 
good  for  roe-deer. 

Suitable  fodder  are  oats,  acorns  and  foliage  ;  they  eat  hay 
only  as  a  last  resource,  when  it  is  given  quite  dry  and  hung 
up  in  little  bundles  under  the  shelter  of  trees  or  thatched 
coverings  and  not  strewn  on  the  ground.  Lopping  branches 
of  silver-fir,  aspen,  sallow,  etc.,  in  winter  is  very  useful. 

Fences  against  roe-deer  need  only  be  5  to  6  feet  high. 

Scarecrows  are  of  little  good,  as  the  roes  soon  become 
accustomed  to  them. 


WILD    PIGS.  Ill 

Smearing  dnng,  petroleum,  or  asafoetida  on  cultivations  is 
useful. 

Young  coniferous  cultivations  may  be  tarred,  as  for  red-deer, 
but  with  deep  snow  it  is  better  to  lime  them.  The  cost  of 
tarring  is  5^/.  to  8^^/.  per  1,000  plants,  at  a  daily  wage  of  Id. 
to  9(/.,  and  tar  at  Is.  9d.  per  cwt. 

To  protect  exotics  (Douglas-fir,  etc.),  saplings  may  be 
encircled  at  about  H  feet  from  the  ground  with  a  piece  of 
paper  as  broad  as  the  hand,  fastened  with  string,  or  they  may 
be  surrounded  with  thorns,  or  by  three  jagged  stakes. 


Section  V. — Wild  Pigs. 
1.  Damage  Done. 

The  wild  pig  does  damage  similar  to  that  done  by  the  tame 
pig,  which  has  been  already  described,  besides  pulling-up 
fresh  transjdants,  and  destroying  mound-planting,  and  birds'- 
nests.  As  regards  sport,  it  does  much  harm  by  killing  fawns, 
leverets,  etc. 

Of  late,  in  the  Lower  Ehine  districts  and  also  in  the  Ardennes, 
pigs  have  so  largely  increased  in  the  forests,  and  do  so  much 
damage  to  the  agricultural  crops,  that  it  has  become  neces- 
sary to  hold  battues,  and  fix  a  price  for  their  destruction. 
From  a  forest  point  of  view,  however,  wild  pigs  do  much  less 
damage  than  other  game. 

They  may,  however,  do  a  considerable  amount  of  good  by 
breaking-up  the  soil,  burying  fruits  and  seeds  and  by  the 
destruction  of  mice  and  hurtful  insects. 

2.  Protective  Rules. 

Feeding  with  turnips,  potatoes,  oats,  peas,  acorns,  wild 
fruit,  etc.,  so  as  to  keep  the  pigs  from  injuring  forest  plants. 

Fences  against  pigs  should  be  about  6  feet  higli  and  strongly 
built.  Wild  pigs  travel  considerable  distances  by  night,  and 
in  France  have  been  found  to  abandon  forests  where  there  is 
much  wire-netting. 


112 


PROTECTION    AGAINST    ANIMALS. 


Traps  can  be  used  to  catch  pigs.  A  pit  about  6  feet  deep 
and  broad  is  dug,  with  walls  vertical  or  even  sloping  inwards. 
A  light  covering  of  poles,  brushwood  and  moss  is  covered  with 
soil,  dead  leaves,  etc.,  resembling  the  Htter  on  the  ground. 
Such    traps  should  be   made   near    wallowing-plaees   in  the 


Fig.  30. — Rolnnia  guawed  by  hare 
{not.  size). 


Fig.  31. — Beech  gnawed  by  hare 
(»(it.  size). 


breeding  season  (November  to  January).  In  making  these 
traps  the  greatest  care  must  be  taken,  the  workmen  must  not 
smoke  nor  eat  their  food  near  the  trap,  and  the  earth  dug  out 
must  be  removed  to  some  distance.  Another  excellent  method 
for  catching  wild  pigs  is  described  in  the  "  Indian  Forester," 
vol.  xi.,  p.  530. 


WILD   PIGS. 


lis 


Pigs,  when  numerous  in  woods  bordering  on  fields,  must  be 
kept  down  by  battue-shooting.  This  is  much  more  efficacious 
than  trapping,  which  has  almost  been  abandoned  since  1878 
in  the  Treves  district.  Thus,  in  the  districts  of  Treves  and 
Coblenz  (1872-75),  658  and  257  pigs  were  shot,  or  respectively 
nine  times  and  three  times  as  many  as  those  trapped. 

The  last  wild  pig  was  killed  in  England  about- 1593,  in 
Chartley  Forest,  Staffordshire  (J.  E.  Harting),  but  they  prob- 
ably lingered  on  to  a  later  date  in  Scotland  and  Ireland.  The 
Indian  wild  pig  (.S^.  cristatus)  differs  very  slightly  from  S.  scrofa. 
A  large  Indian  boar  may  weigh  over  300  lbs.  and  may  stand 
up  to  42^  inches  at  the  shoulder.  Pig-sticking  with  the  lance 
on  horseback  is  a  favourite  pastime  in  India.  Wild  pigs  are 
numerous  in  Indian  forests,  where,  however,  they  do  little 
damage,  though  very  destructive  to  agricultural  crops. 


lU 
CHAPTER   11. 

PROTECTION    AGAINST    RODENTS. 

Section  I. — General  Account. 

1.  List  of  Injurious  Species. 

Hares  and  lUtldnts  {Leporidac). 

The  common  hare  {Lepus  enropceus,  L.). 
The  mountain  hare  (L.  tiinidus,  L.). 
The  raljbit  (L.  ctDiicuIus,  L.). 

Sqairreh  (Sciuridac) . 
The  common  squirrel  {Sciuriis  viih/aris,  L.). 

Dormice  ( Mijo.iidae). 

The  loir  {Mijoxus  f/lis,  Schreb.). 

The  common  dormouse  {M.  aveUanarius,  L.). 

The  garden  dormouse  [M.  nitela,  Wagn.). 

Jlice  (Mvrii /(//'). 

The  common  wood-mouse  {Mas  silvaticus,  L.). 
The  long-tailed  field  mouse  {M.  agrarius,  Pall.). 

Voles  {Ari'irolidae). 

The  water-rat  (Arricola  amphihius,  J)esm.). 

The  field  vole,  or  short-tailed  field  mouse  {A.  atirestis,  Bias.). 

The  southern  field  vole  {A.  arvalis,  Selys.). 

The  hank  vole  {Jlypudceus  {A.)  (ilareolns,  Wagn.). 

2.  Damaric  Done. 
The  above-mentioned  animals  damage  the  forest  by  eating 
fruits  and  seeds,  and  gnawing  young  growth,  breaking-oft" 
young  shoots,  eating  buds,  peeling  bark,  and  burrowing  in  the 
ground.  Pabbits,  mice  and  voles  do  most  harm,  on  account 
of  their  destructive  voracity  and   their  enormous  powers  of 


HARES.  115 

breeding.     Young  growth,  sowings  and  plantations  are  often 
completely  destroyed  by  them. 

The  damage  done  by  liares,  squirrels  and  dormice  is  not 
so  great,  being  confined  to  individual  plants,  and  these  animals 
do  not  become  so  numerous  as  rabbits,  mice  and  voles. 

3.  Protective  Rules. 

Proper  precautions  must  be  taken  in  the  reproduction, 
tending  and  utilisation  of  woods.  Enemies  of  these  animals 
must  be  spared.  Shooting,  trapping,  poisoning  may  be 
employed.     More   detail  is  given    separately   for  each  kind. 

Section  II.— Haees. 
1.  Damage  Done. 

The  common  hare  is  found  throughout  Europe,  except  in 
mountains  and  the  extreme  north.  In  Scotland  it  occurs 
only  in  tiie  lowlands  and  in  valleys.  In  the  British  Isles  the 
mountain  hare  is  met  with  only  in  Scotland,  and  in  Ireland, 
where  it  is  known  as  the  blue  hare.  At  lower  latitudes  it 
turns  white  during  winter,  but  remains  white  throughout  the 
year  in  the  extreme  north. 

The  hare  injures  woody  plants  in  winter  by  biting  and 
gnawing  their  bark.  Buds  and  young  shoots  of  beech,  horn- 
beam, elm,  ash,  maple  and  aspen  are  chiefly  bitten,  the 
conifers  less,  and  spruce  and  Scots  pine  least  of  all. 

As  the  hare  affects  certain  localities,  the  damage  is  restricted 
in  area,  but  very  extensive  where  it  prevails ;  so  that  a  single 
hungry  hare  may  cause  considerable  damage  in  young  growth 
of  beech  on  sunny  situations,  which  it  frequents  in  winter. 
The  sharp  teeth,  cutting  in  pairs,  give  very  distinct  markings 
on  plants  attacked  by  hares. 

As  regards  peeling,  in  snowy  winters  the  one-year-old  shoots 
of  the  robinia  and  other  L<'(iuminos(e,  including  broom,  are 
frequently  stripped  of  bark,  and  the  wood  gnawed  as  shown  in 
Fig.  30.  Among  ordinary  forest  plants,  young  beech  and 
sycamore  sufifer  most  from  peeling  ;  older  trees  with  rough  bark 
escape.  The  hare  frequently  damages  fruit-trees  in  orchards, 
chiefly  the  apple,  next  the  cherry,  least  of  all,  the  pear. 

I  2 


no  PROTECTION    AGAINST    ANIMALS. 

2.  Protective  Rules. 

{(i)  Fence  nurseries,  esi)ecially  those  of  fruit-trees,  with 
hedges  or  dead  thorns,  or  with  wire-netting  4  feet  high. 

(b)  Bind  fruit-trees  from  Novemher  till  April  with  thorns 
l>ranches  of  conifers  or  wheat  straw. 

((•)  Fruit-trees  may  be  smeared  with  stinking  substances. 
A  mixture  of  10  quarts  of  bullock's  blood,  ^  lb.  of  asafcetida 
dissolved  in  warm  water,  and  some  lime  and  cow-dung  may 
be  used. 

((/)   Shoot  hares,  especially  in  broad  leaved  woods. 

Section  III. — Rabbits. 

A  pair  of  rabl)its  during  spring  and  summer  may  produce 
about  5 — 8  young  ones  every  4 — 5  weeks.  Young  rabbits 
begin  to  breed  when  six  weeks  old,  so  that  in  New  South 
Wales,  under  favourable  circumstances,  it  has  been  found 
that  a  pair  of  rabbits  may  produce  13,718,000  in  three  years. 
Rabbits  cannot  withstand  the  great  winter-cold  of  the  higher 
Ardennes,  between  1,200 — 2,000  feet,  but  in  milder  situations 
throughout  Britain  and  the  North  of  France  they  are  the 
most  destructive  enemies  of  broadleaved  woods. 

1.  Damcujc  Do)ie. 

Rabbits,  which  are  chiefly  found  on  hilly  and  sandy  ground, 
do  the  same  kind  of  damage  to  young  growth  as  hares,  besides 
injuring  the  roots  of  plants  by  burrowing.  They  are  not  nearly 
so  destructive  in  biting  off  young  shoots  as  by  gnawing  at  the 
bark  of  plants.  The  seedlings  of  the  Scots  pine,  the  chief 
species  on  sandy  soils,  suffer  most  of  all  from  biting,  and  next 
to  this  black  pine  and  larch,  also  oak  and  ash. 

As  regards  gnawing,  nearly  all  species  suffer,  chiefly  horn- 
beam, ash,  robinia,  aspen,  sallow,  hazel  and  fruit  trees.  This 
form  of  damage  is  most  considerable  in  snowy  winters,  1894-5, 
for  instance.  Fig.  32  shows  the  teeth-marks  of  rabbits  very 
clearly.  Not  only  is  young  growth  attacked,  but  where  rabbits 
are  numerous,  and  when  the  ground  is  frozen  or  covered  with 
snow,  the  base  of  large  beech  and  other  trees  is  barked,  and 
the  trees  may  be  completely  girdled.  From  experience  in 
Windsor  Forest,  which  is  overrun  with  these  pests,  so  that 


RABBITS. 


117 


the  underwood,  so  valuable  in  oak  forests,  which  was  plentiful 
twenty-five  years  ago,  has  now  disappeared  over  large  areas, 
the  sycamore  appears  to  suffer  less  than  other  species,  and 
rabbits  will  not  touch  Ehododendron  j^ontirum,  M'hich  some- 
times forms  a  dense  underwood  in 
parts  of  the  forest  infested  by  them. 
Hedges  of  whitethorn  are  often  com- 
pletely destroyed  by  the  peeling  of 
rabbits. 

By  burrowing,  rabbits  do  mucli 
harm  to  cultivations  and  youn.i; 
seedlings.  Hares  avoid  places 
frequented  by  rabbits. 


2.  Protective  Measures. 

(a)  Protection  of  foxes,  pole-cats, 
martens,  stoats  and  weasels,  which 
are  the  natural  enemies  of  rabbits. 
A  family  of  stoats  may  kill  fifty 
rabbits  in  a  week. 

(b)  Careful  fencing  4  feet  high, 
and  use  of  wire-netting  buried  partly 
in  the  ground  and  sloping  outside 
the  area  to  be  protected. 

((,')  Valuable  trees  may  be  l)ound 
round  with  thorns  or  wire-netting,  or 
their  bases  smeared  with  coal  tar. 

(</)  Use  of  traps  or  poisons, 
or  smoking-out  the  burrows  with 
sulphur.  In  Australia,  poisoned 
grain  is  buried  in  shallow  trenches 
to  kill  rabbits.  Sheep  are  not  thus 
endangered.  Between  April  and 
October,  1890,  in  a  forest  near  Kiistrin,  2,339  rabbits  were 
trapped,  in  traps  supplied  by  Grell,  of  Haynau,  Silesia, 
costing  2s.  each.  A  farmer  in  South  Devon  informed  me 
that  stoats,  being  very  reckless,  are  readily  caught  in  traps 
set   for  rabbits,  and    that    since   rabbits  have  been   trapped 


Fig.  :52. — W'illow  gnawed  by 
rabbits  («a<.  size'). 


lis  PROTECTION    AOAINST    ANIMALS. 

in  his  neiglibourhood,   the    stoats,  which   are  their  greatest 
enemies,  have  disappeared. 

(<?)  Ferreting,  the  ferret  being  merely  a  domesticated  variety 
of  pole-cat.  This  is  usually  followed  from  October  till  the  end 
of  February,  when  rabbits  do  not  generally  have  young.  The 
ferret  is  sent  into  the  burrow,  and  a  net  placed  at  its  opening 
into  which  the  rabbits  run,  or  they  may  be  shot  when  driven 
by  the  ferret  out  of  their  burrows. 

(/)  Shooting.  This  is  very  useful,  if  carried  on  in  summer 
when  the  rabbits  are  breeding  and  does  are  easily  shot, 
especially  in  young  plantations. 

Every  Enclosure  Act  allowing  planting  in  Crown  forests 
states,  that  no  rabbits  should  be  kept,  on  any  pretence 
whatever. 

Suction  IV. — The  Squibeel. 
1.  Damage  Done. 

The  damage  done  by  squirrels  is  greater  than  is  generally 
imagined.  They  eat  fruits  and  seeds,  cotyledons  and  buds, 
and  bite  off  young  shoots,  remove  bark,  and  destroy  eggs  and 
young  birds.  Their  utility  in  destroying  beetles,  larva?  of  saw- 
flies  and  other  insects,  does  not  compensate  for  the  liarm  they  do. 

In  1901,  i'SO  was  spent  in  the  Countess  of  Seatield's  estate 
at  Granttown  in  rewards  for  killing  squirrels  at  ^^.d.  per  head. 
They  had  done  much  damage  by  girdling  larch  and  Scots  pine. 

a.  Destruction  of  Fruits  and  Sepdlinys. 
Beech-nuts,  acorns,  hazel-nuts  and  seeds  of  spruce  and  Scots 
pine  constitute  the  chief  food  of  the  squirrel.     Besides  these, 
it  eats  seeds  of  other  conifers,  fruits  of  horn- 
beam and  maple  and  of  mountain-ash,  and 
walnuts,  apples  and  other  garden  fruits.     A 
large   proportion   of   the   annual    supply  of 
fruit   may  thus  be  lost,    and  in  coniferous 
woods,  natural  reproduction  may  be  greatly 
Fig.  33.— llazel-mit     I'educed.     Beech-nuts  are  often  eaten  in  their 
opened  by  squirril.      involucres  by  squirrels  from  September. 

Fig.  33  shows  how  the  hazel-nut  is 
attacked  by  this  little  animal,  and  Figs.  34  and  35  how  the 
scales  are  stripped  from  the  spruce-cones  so  that  it  can  get 


SQUIRRELS. 


119 


at  the  seeds.     Heaps  of  broken  scales  from  cones  lying  under 
the  trees  show  how  busy  the  squirrel  has  been. 

More  harm  again  is  done  by  the  squirrel  digging-out  seeds 
and  cotyledons  from  the  ground,  and  biting-off  cotyledons  of 
the   beech    in    seed-beds    and    reproduction-areas.      It    also 


Fig.  34. — Spruce-cone  stripped  of 
scales  by  squirrel. 


Fig-.  35. — I'ortiou  of  spruce-cone  attacked 
by  squirrel. 


uproots  young  oak-plants  to  get  at  the  remains  of  the  acorns. 
Indian  squirrels  have  similar  proclivities  to  the  above-men- 
tioned species  and  sometimes  completely  strip  trees  of  their 
fruit,  besides  being  very  destructive  to  peas,  etc.,  in  vegetable- 
gardens. 

b.   Eatinii  Jliols  ami  Bituifj  off  Tirigs. 

As  regards  buds,  the   squirrel  prefers   those  of  the  inflo- 
rescence, which  are  richer  in  nitrogenous  substances  and  more 


120 


PROTECTION    AGAINST    ANIMALS. 


nourishing  than  the  foUage-bnds.  Spruce  and  Scots  pine 
are  preferred,  but  silver-fir  is  also  attacked  in  this  way.  The 
destruction  of  these  buds,  in  snowy  winters,  may  entirely 
prevent  seed  from  being  produced.  The  methods  pursued  by 
the  squirrel  in  eating  the  buds  differ  according  to  the  ag^, 
height,  and  strength  of  the  plants  attacked.  In  plantations 
and  thickets,  from  1  to  6  feet  high,  which  are  not  yet  provided 


Fi.i,^-;.  36  and  37.— T 
Points  where  twigs  ai( 


igs  bitien  off  by  squirrel  (nut.  , 

nttvu  off.     l>.   Bases  of  bitteii-off  buds. 


with  flowering-buds,  the  squirrels  bite-off  the  top  of  the 
previous  year's  shoot,  and  the  side-shoots  of  the  last  verticil, 
the  buds  of  which  are  also  eaten.  Scots  pines  injured  in  this 
way,  develop  new  leaders  from  buds  just  below  the  point  of 
attack,  whilst  in  the  case  of  spruce,  an  uninjured  side-shoot 
from  the  last  verticil  becomes  a  leader.  In  the  case  of  poles 
and  trees  of  these  species,  the  squirrel  bites-off  the  most 
external  little  shoots  on  which  are  the  male  inflorescence- 
buds,  and  then,  holding  the  twig  with  its  fore  feet,  goes  back 
to  the  branch  to  eat  the  buds.     It  then  lets  the  twig  fall  to 


SQUIRRELS. 


121 


to  the  ground,     Probably  the  female  inflorescence-buds  are 

eaten    as    well,    and  very   few    cones  are  formed    on    trees 

where  squirrels  have  lived  during  the  winter.     Silver-lir  is 

also  sirailarl}^  attacked. 

« In   the   summer  also,  shoots  of  various 

lengths  up  to  8  inches  are  bitten  off  spruce 

trees  by  the  squirrel  and  gnawed,  as  at  tliis 

time  there  are  no  seeds  or  buds  to  eat. 

c.  Peeling  and  Girdling. 

Tlie  peeling  and  girdling  of  young  plants 
of  larch,  Scots  pine  and  silver-fir,  also  of 
beech,  hornbeam,  aspen,  willows  and  oak 
have  been  noticed,  and  are  becoming  serious 
in  Britain.     Plants  fifteen  to  thirty  years 


Figs.  38  and  39.— Spiral  girdlings  of  Scots 
pine  by  squirrel. 


Fig.  40.— Girdling  of 
Scots  pine  bv  squir- 
rel  (j). 


122 


PROTECTION    ACJAINST    ANIMALS. 


old  suffer  most,  but  also  sixty-3'ears-old  woods.  Tliis  is  done 
from  May  to  July  chiefly  in  dry  years.  The  damage  is  done 
to  the  stem  in  the  crown  where  the  squirrel  sits,  and  is 
sometimes  in  rings  or  spirals,  at  other  times  quite  irreguhir ; 
as  it  goes  down  to  the  sai)wood,  the  injured  stems  may  ^ie 
above  the  peeled  place,  as  they  sometimes  do  by  hundreds. 

(1.  Destrurlion  of  Yot/ii//  Ilinh. 

During  the  breeding  season  of  birds,  the  S(juirrel  frequently 
attacks  their  young,  killing  them  and  eating  their  heads. 


2.  Protective  RhIch. 

Protection  of  the  pine-marten  {Miistcla  iiutrtcs),  a  great 
enemy  of  the  squirreh 

Shooting,  with  the  help  of  dogs,  in  spruce  seed-years,  and 
near  nurseries. 

Section  Y, — Doiniioi':. 

1.  Damage  Thmc. 

Dormice  are  squirrel-like  animals,  with  bushy  tails,  and  as 
they  move  about  at  night, 
chiefly  in  broadleaved  forest, 
it  is  difficult  to  state  precisely 
the  amount  of  damage  they  do. 
The  loir  {Mi/oxus  glis,  in 
German,  Siebenschli'ifer),  the 
largest  European  species  of 
dormouse,  is  found  in  southern 
Europe,  but  not  in  the  British 
Isles.  It  feeds  on  mast  of  all 
kinds  and  also  on  spruce  and 
other  seeds,  and  orchard-fruit, 
))ites-off  the  leading  shoots  of 
beech  and  silver-fir,  and  in 
spring,  barks  young  stems,  and 
robs  birds'  nests,  doing  injury 
of  a  similar  nature  to  that  done  by  squirrels. 

It  collects  a  provision  for  the  winter  in  holes,  but  passes 


41. — Girdliuf 
of  alder  Ijy  dor- 
mii'C. 


DORMICE    AND    MICE. 


123 


most  of  this  season  asleep.  Barking  is  clone  in  strips,  or 
rings,  on  ten-  to  twentyfive-years-old  trees  of  birch,  hornbeam, 
hazel,  etc.,  also  of  larch  and  silver-fir. 

The  loir  also  bites-off  spruce-shoots  in  order  to  strip  them 
(if  their  needles  and  chew  them,  spitting  out 
the  debris. 

The  garden-dormouse  {M.  qnercinus,  L.) 
is  rarer  than  the  former,  but  has  a  similar 
habitat,  going,  however,  further  north  ;  it  is 
fond  of  orchard- fruit,  and  also  attacks  forest 
fruits  like  the  loir. 

The  common  dormouse  (.1/.  avellanarius, 
L.),  chiefly  inhabits  coppice,  especially 
hazel-coppice,  and  is  found  all  over  Europe, 
from  Sweden  to  Northern  Turkey,  but  is 
less  common  in  the  south  than  the  other 
two  species.  It  does  similar  damage  to  them, 
but  on  a  smaller  scale,  and  owing  to  its  fond- 
ness for  hazel-nuts,  is  termed  Hazelmaus  in 
Germany. 

2.  Protective  Rules. 

Dormice  may  be  caught  like  rats  in  iron 
traps  baited  with  bacon,  or  for  the  last 
species,  in  wire-traps  with  almonds  as  a  bait. 

In  the  extensive  beech  forests  of  Carinthia, 
the  capture  of  the  loir  is  actively  pursued, 
its  Hesh,  which  becomes  very  fat  in  autumn, 
being  eaten,  while  the  skins  are  exported,     pj„   43.  —  Girdling 
as  many  as  800,000  l;eing  captured  in  good        of  beech  by  dor- 
years  of  beech-mast.  ™'^*^- 


Section  VI. — Mice. 

1.  DcuiicKje  Done. 

Forest  mice,  especially  the  long-tailed  field-mouse  {Mus 
silraticus,  L.),  and  to  a  less  degree  Mus  agrarius,  Pall.,  are 
very  destructive  by  eating  forest  fruits  and  seeds,  biting  and 
gnawing,  burrowing  in  the  ground  and  killing  small  birds. 


121  PROTECTION    AfMINST    ANnfALS. 

Chiefly  beech  and  oak-mast  and  hazel-nuts  are  eaten,  and 
autumn-sowinfTS  suffer  more  than  those  made  in  the  spring.  , 

In  winter,  and  when  the  snow  is  on  the  ground,  they  gnaw 
buds,  tender  shoots,  bark  and  sapwood  of  young  forest  phmts, 
from  2  to  15  years  old.  Broadleaved  species  chiefly  suffer, 
such  as  hornbeam,  beech,  ash,  maple,  hazel,  sallow,  and  also 
oak,  elm,  aspen,  etc.  Handsome  thorn-trees  are  often  girdled 
by  them.  They  gnaw  the  bark  of  plants  up  to  3  feet  and 
higher  from  the  ground,  somewhat  higher  than  voles,  from 
which  they  can  be  distinguished  in  this  way.  Young  stems 
up  to  2  inches  in  diameter  at  the  base  are  often  gnawed 
through,  and  promising  cultivations  are  thus  ruined. 

By  their  burrowing,  many  plants  are  uprooted  and  die, 
but  this  kind  of  damage  is  done  on  a  much  greater  scale  by 
voles. 

Mice  are  chiefly  destructive  on  sunny  aspects  in  young  woods 
full  of  grass  undergrowth.  Their  powers  of  reproduction  in 
dry  summers  are  quite  extraordinary. 

Rats  are  frequently  destructive  to  forests  in  India.  There 
was  a  plague  of  rats  in  Berar,  in  1902,  described  by  E.  E. 
Fernandez  (Indian  Forester,  April).  They  destroyed  cotton 
goods  and  grain  and  gnawed  the  bark  of  teak,  up  to  3  feet 
in  girth,  also  of  Butea  frondosa,  the  lac  tree,  and  other 
species. 

2.  Protective  Rides. 

These  are  about  the  same  as  against  voles,  and  will 
therefore  be  given  in  full  further  on,  but  as  the  long- tailed 
field-mouse  lives  in  forests  throughout  the  year,  it  is  more 
difficult  to  ward  against  its  attacks  than  against  those  of  voles, 
which  come  from  the  fields  into  the  forest  during  winter.  The 
chief  remedy  is  to  protect  its  enemies,  the  stoat,  weasel,  fox, 
owls,  etc. 

Section  VIL — Voles. 

Voles  are  distinguished  from  mice  by  their  thicker,  shorter 
head,  by  having  ears  buried  in  their  fur,  short  legs  and  tail; 
true  mice  having  a  pointed  head,  large  ears  and  a  long  tail. 


MICE    AND    VOLES.  125 

1.  Damage  Done. 

'Voles  in  daytime  live  chiefly  in  the  soil,  into  which  they 
burrow  in  all  directions.  Their  burrows  are  just  below  the 
surface  of  the  ground,  and  by  burrowing  in  forest  nurseries, 
plantations  and  natural  regeneration-areas,  they  uproot  thou- 
sands of  plants  and  injure  drains  and  ditches.  They  are 
chiefly  vegetable-eaters,  devouring  fruits  and  seeds,  cutting 
through  the  roots  of  young  plants  in  the  ground,  gnawing 
their  shoots,  but  they  also  attack  young  birds. 

During  winter  they  gnaw  the  bark  of  plants  chiefly  of  broad- 
leaved  species  from  the  collum  up  to  ten  inches,  or  as  far  as 
the  grass  reaches,  in  strips  or  rings. 

Voles  breed  much  more  rapidly  than  mice,  the  southern  field- 
vole  {Arvic(Aa  arvalis,  Selys.)*  being  especially  reproductive. 

The  water-vole  {A.  am2)hihius,  Desm.),  and  the  common 
field-vole  {A.  af/restis,  Bias.),  do  the  most  damage.  The  water- 
vole  lives  not  only  near  water,  but  also  in  the  forest,  and  does 
much  damage  by  burrowing,  and  by  cutting-off  the  tap-root 
of  stems  up  to  the  thickness  of  a  man's  arm,  that  naturally 
kills  them.  Oak  and  ash  suffer  most  in  this  way,  also  poplars, 
willows,  apple-trees,  etc. ;  less :  beech  and  conifers.  The  water- 
vole  also  frequently  injures  banks  and  dams ;  it  has  done 
much  damage  in  the  forests  occasionally  inundated  by  the 
Danube,  but  is  fortunately  never  very  numerous. 

The  bank*- vole  {HypiuUeus  (jlareolus,  Wagn.)  is  extremely 
active,  and  inhabits  chiefly  the  borders  of  forests,  bushy 
land  amongst  fields,  and  forest-glades  with  advance-growth, 
rather  than  dense  forest.  It  gnaws  larches,  black  pines, 
aspen,  and  other  trees  and  shrubs,  and  eats  and  carries  off 
the  pine-buds. 

The  common  field-vole  {Arvicola  agrestis,  Bias.)  is  the 
greatest  scourge  of  the  agriculturist,  and  comes  from  the 
fields  into  light  forests,  where  it  does  enormous  damage.  In 
the  winters  of  1822-23,  1830-31,  1840-41,  1856-57,  1861-62, 
1868-64,  1870-71,  1871-72,  1872-73,  1878-79,  1889-90, 
1892-93,  this  species  was  chief  among  the  swarms  of  mice 

*  About  75  per  cent,  of  them  are  0,  and  a  mother  vole  has  eight  to 
ten  young  every  six  to  eight  weeks,  from  March  till  late  in  autumn.  A  o  begins 
breeding  when  eight  weeks  old,  and  may  have  10,000  descendants  in  a  year. 


126 


PROTECTION    AGAINST    ANIMALS. 


wliich  destroyed  the 
young  plantations  on 
thou.sands  of  acres  in 
Germany.  The  destruc- 
tion is  greatest  when  it 
collects  in  swarms  and 
wanders  from  place  to 
place.  Voles  and  mice 
are  specially  destructive 
in  forest  nurseries. 

A    description    of    the 


Fii;.  46. — Apple-tree  gnawed  by  hares  («  b), 
and  by  mice  (I  c)  (ttat.  size). 


Fig.  44.— Beech  Fig.  45.— Alder 

gnawed       by  gnawed      by 

mice        {tiat.  mice       {nat. 

size).  size). 


damage  done  in  1814  by  this  species  and  the  long-tailed  field- 
mouse  is  given  in  Nicholls'  *  account  of  the  Forest  of  Dean. 

•   rublished  by  John  Murray,  Albeiiiarle  Street,  London,  1858. 


MICK    AND    VOLES.  127 

They  destroyed  all  the  young  oak-saplings  in  the  forest 
except  four  or  five  per  acre,  eating  through  the  roots  just 
])elo\v  the  surface  of  the  ground.  The  long-tailed  species 
was  found  chiefly  on  wet  ground,  and  the  vole  everywhere. 
To  exterminate  these  pests,  trenches  2  feet  deep  were  dug 
20  yards  apart,  and  100,000  tails  were  brought  in  for  reward. 
Polecats,  hawks,  kites  and  owls  increased  enormously,  and 
the  mice  ate  one  another  in  the  trenches.  Much  damage 
was  also  done  by  field-voles  in  the  Lowlands  of  Scotland  in 
1891-92.  This  species  prefers  hornbeam,  beech,  ash,  hazel 
and  sallow,  but  it  also  attacks  all  broadleaved  species  as 
well  as  pines  and  larch.  It  is  specially  fond  of  white- 
thorn. Young  plants  two  to  five  years  old  are  gnawed 
through  at  the  surface  of  the  soil,  or  peeled  of  bark,  or  bitten 
through  above  ground,  or  stripped  of  their  side- shoots. 
Older  plants  and  even  poles  up  to  10  inches  in  girth  are 
stripped  of  their  bark  up  to  a  foot  from  the  ground  and 
killed.  Voles  strip  the  scales  from  the  fir-cones  and  eat  the 
seeds,  they  also  eat  grass  with  its  rhizomes,  thus  destroying 
extensive  pastures. 

The  southern  field-vole  living  on  the  confines  of  forests  in 
well-watered  situations  gnaws  the  roots  and  bark  of  beech  and 
other  trees  in  hard  winters. 

The  only  use  of  voles  is  that  they  eat  larvfe,  snails  and 
slugs. 

2.  Protective  Hides. 

(a)  Woodlands  bordering  on  fields  should  be  separated  from 
them  by  ditches.     Further  reference  will  be  made  to  this. 

(h)  Forest  nurseries  should  not  usually  be  made  near 
fields.  "Wherever  this  cannot  be  avoided,  rule  (<i)  should  be 
followed. 

(c)  In  years  when  mice  are  abundant,  autumn- sowings, 
especially  of  acorns  and  beech-mast,  should  be  abandoned  ;  in 
any  case,  plenty  of  seed  must  be  sown,  and  covered  deeper 
than  usual,  but  it  is  better  to  sow  late  in  the  spring,  or  to  use 
transplants. 

{(l)  In  forest  nurseries  broadcast-sowing  in  seed-beds  is 
preferable  to  sowing  in   drills.     Small  pieces  of   furze  may 


128  PROTECTION   AGAINST    ANIMALS. 

be  placed  between  acorns  or  other  seeds  in  the  nurserj'-beds. 
The  seed  should  be  covered  with  red  lead  b}^  slightly  wetting  it 
and  rubbing  the  red  lead  on  to  the  seeds, 

(e)  For  sowings  in  the  forest,  the  following  precautions  are 
recommended  : — Soaking  the  seeds  for  half  an  hour  in  a  2  per 
cent,  solution  of  carbolic  acid  in  water ;  10  per  cent,  of  the 
acid  will  kill  the  seeds.  Acorns  may  also  be  soaked  in  a 
decoction  of  quassia.  The  seed-beds  may  be  covered  with  a 
layer,  2  inches  thick,  of  old  tan  or  spruce  branches,  or  strewn 
with  calcium  chloiide,  which  is  also  a  protection  against 
certain  insects.     Seeds  may  be  covered  with  red  lead. 

if)  Endangered  saplings  in  nurseries  may  be  wrapped 
round  spirally  with  4-8  inches  wide  strips  of  asphalt  paper 
and  their  barks  surrounded  with  asphalt  tar.  The  scent  of 
this  keeps  off  the  mice.  Hesse  considers  coal-tar  as  hurtful 
to  plants.  Various  advertised  preparations  may  be  smeared 
over  the  plants,  such  as  a  mixture  of  cart-grease,  petrol,  alum 
and  tallow. 

ig)  Felling-areas  with  grass-undergrowth  should  be  pastured 
down  in  summer  and  autumn  by  cattle  or  sheep.  The  grass 
protects  the  mice  from  observation,  and  renders  the  bark  of 
plants  in  it  soft  and  fresh,  which  the  mice  like.  The  cattle 
disturb  and  trample  down  many  mice. 

(//)  Beech  seeding-fellings  should  be  dark  in  order  to  keep 
down  the  grass. 

(i)  Pigs  may  be  admitted  into  the  forest  as  long  as  the  soil 
is  loose,  especially  near  nurseries.  They  root-up  the  ground, 
disturb  the  mice,  destroy  their  young,  fill  up  their  burrows, 
and  also  trample-down  and  eat  many  mice. 

ij)  lienioval  of  low  undergrowth,  which  shelters  the  micQ. 

(A)  Branches  of  softwoods  or  hornbeam  may  be  spread 
about  in  young  beech-woods,  to  attract  the  mice  from  the 
beech.  They  must  however  be  frequently  replaced,  as  dry 
branches  are  no  longer  gnawed,  and  then  the  remedy  does 
more  harm  than  good,  the  branches  having  attracted  mice 
into  the  wood.     This  is  a  good  precaution  against  the  southern 

field-vole. 

(l)  Protection  of  Enemies.— Beve  Vie  muiit  restrict  ourselves 
to  the  protection  of    mice-destroyers  which    may  not  do  so 


-MICK    AND    VOLES. 


129 


much  injury  in  another  direction  as  to  outweigh  their  use- 
fuhiess  in  killing  mice  and  voles.  The  following  animals  are 
useful  in  this  way  : — 

Mammals. 

The  pole-cat  {Piitoriusfoctidits,  Gray),  the  stoat  (/*.  crmineiis, 
Ow.),  the  weasel  {P.  nilgaris,  Eich.),  the  hadger  (Mdcs  taxus, 
Pall.),  the  mole  {Talpa  eurojMea,  L.),  and  the  hedgehog 
{Erinacaas  eiiropaeits,  L.),  also  the  shrews,  especially  Sorex 
nih/aris,  L.     The  mole  does  not  inhabit  Ireland. 

The  first  three  beasts  also  plunder  nests  and  eat  eggs,  young 
birds  and  leverets.    The  badger  eats  fruits,  mast  and  pheasants' 


(B)  Surface  of  ground. 

(rt)  Upper  gallery. 

(6)  Descending  passages. 

(f)  Lower  gallery. 

{d)  Ascending  passages. 


-  Diagram  ol  niole-litap. 

(f)  Central  chamber. 
(/)  Passage  to  chamber. 
(ff)  Moles'  run. 
(/()  Diverging  ruus  from  lower  gallery. 


eggs.  The  mole  is  hurtful  to  forest  nurseries  from  its  habit  of 
burrowing  and  throwing-up  small  heaps  of  soil.  The  hedge.- 
hog  attacks  nests.  All  these  animals,  however,  are  much 
more  useful  than  hurtful.  The  well-known  and  much  abused 
mole  hunts  for  mice,  crickets,  snails,  slugs  and  grubs,  and  is 
always  at  hand  where  these  creatures  abound,  and  extremely 
useful  in  destroying  them.  It  increases  rapidly,  has  3 — 5 
young  at  a  birth,  and  two  broods  in  the  year,  in  May  and 
August,  and  is  very  voracious.     Its  ingenious  nest  (Fig.  47) 

F.P.  K 


IBO  PROTECTION    AGAINST    ANIMALS. 

affords  means  of    escape  when  pursued    by  a   rat,  or  other 
enemy. 

A  limited  protection  may  also  be  afforded  Avhen  mice  are 
swarming,  to  the  fox  {Canis  vidpes,  L.),  the  pine-marten 
(Mustelainartes,  L.),  the  beech-marten  {Mastela  f oina,  Briss.) 
and  the  wild  cat  {Felis  cat  us,  L.),  in  spite  of  the  damage  they 
may  do  to  game.  A  full-grown  fox  will  eat  two  or  three 
dozen  mice  daily,  and  in  S.  Sweden,  where  foxes  are  numerous, 
there  are  no  plagues  of  mice. 


Birds.* 

The  following  birds  are  extremely  useful  in  destroying 
mice  : — The  kestrel  {Falco  tinnunculus,  L.)  ;  the  buzzards, 
especially  the  common  buzzard  (Buteo  vnUjaris,  Leach)  ; 
owls,  especially  the  long-eared  and  short-eared  owls  {Otus 
vulgaris,  Flemm.,  and  0.  hrachyotus,  Cuv.) ;  also,  the  tawny 
owl  {Syriiium  Ahico,  Boie),  the  little  owl  {Carine  noctua, 
Scopoli),  and  the  barn-owl  {Strix  flaiiunea,  L.).  To  these 
may  be  added  the  hen-harrier  and  the  marsh-harrier  {Circus 
cyancus  and  C.  dcruginosus).  Mr.  Tegetmeier  states  that  a 
pair  of  barn-owls  brought  food  to  their  nest  5  times  in  three 
hours.  This  probably  meant  150  mice  in  4^  hours.  The 
short-eared  owl  limits  mice  in  day-time  and  appeared  in 
Scotland  in  large  numbers  during  the  plague  of  mice. 

The  rook  {Corvus  frwjUcgus,  L.)  kills  mice,  especially  in 
the  autumn,  so  do  the  black  crow  (C.  corone,  Lam.)  and  the 
hooded  crow  {C.  comix,  L.),  which  are  sometimes  said  to  be 
varieties  of  the  same  species  and  to  interbreed  freely.  The 
above  three  species  of  Corvus  occasionally  attack  acorn.-sow- 
ings,  and  break  off  the  leading  shoots  of  conifers,  and  the 
crow  does  much  damage  by  eating  the  eggs  of  partridges  and 
other  birds,  but  on  the  whole  their  utility  is  greater  than 
their  destructiveness. 

Herons  {Ardea  cinerea)  and  storks  (Ciconia  idha,  L.)  occa- 
sionally feed  on  mice,  and  so  does  the  black-headed  gull 
{Larus  ridibluidus,  L.). 

*  The  scientific  names  for  binls  follow  Yanell,  "  British  Birds,"  4tli  cilition. 
Kevised  by  A.  Newton,  F.U.S.,  and  II.  Saunders,  1874— 8.">. 


MICE    AND    VOLES.  131 

Most  of  llie  other  iiesli-eating  birds  do  too  much  damage  to 
useful  birds  to  deserve  protection. 

3.  llonedial  Measures. 

Remedial  measures  against  mice  may  be  with  or  without 
poison.  The  chief  rule  is  to  adopt  measures  every  year  which 
suit  the  localit}^  so  as  to  prevent  as  far  as  possible  any  extra- 
ordinary increase  in  the  number  of  mice  and  voles.  According 
to  trustworthy  observation,  there  are  far  more  females  than 
males  in  the  spring,  and  mice  should  therefore  be  destroyed 
as  much  as  possible  in  February  and  March.  Private  enter- 
prise, especially  in  forests  where  it  is  difficult  to  get  at  the 
mice,  is  not  sufficient  for  this  purpose,  but  the  State  must 
direct  matters  and  induce  private  persons  to  assist  in  the 
energetic  destruction  of  mice  both  in  fields  and  in  forest,  which 
will  be  to  the  public  advantage. 

a.  PUfaHs. 

Trenches  must  be  dug  in  the  ground,  and  visited  daily  to 
keep  them  clear  from  leaves,  etc.,  and  to  remove  and  kill  the 
captives.  They  should  be  8 — 10  inches  wide,  and  1'2 — 16 
inches  deep,  with  vertical  smooth  walls.  The  base  of  the 
pitfall  must  be  beaten  hard,  and  glazed  earthenware  vessels, 
or  drain-pipes,  one  every  3  or  4  yards,  buried  level  with  the 
bottom  of  the  pitfall.  A  few  grains  of  wheat  act  as  lures  for 
the  mice,  and  those  which  are  found  in  the  pitfall  are  killed 
with  a  pointed  piece  of  coarse  iron  wire  ;  they  will  die  other- 
wise of  starvation.  Such  trenches  are  to  be  recommended 
against  field-mice  along  the  borders  of  fields  and  forests,  and 
around  forest  nurseries  and  seed-granaries.  In  Mecklenburg, 
10,800  mice  were  thus  destroyed  in  autumn,  1872,  between  a 
clover  field  and  a  sown  plantation. 

b.   Traps. 

Traps  are  useful,  especially  against  water-rats  and  bank- 
voles,  and  various  kinds  of  devices  may  be  used  to  trap  mice 
according  to  species  and  local  circumstances. 

h  -1 


132 


PROTECTION    AGAINST    ANIMALS. 


Traps  resembling  sugar-tongs  are  advocated  by  E.  Heyer 
against  the  ^Yater-rat,  as  shown  in  tlie  Figs.  50  and  51.  They 
niust  be    so   i^laced    that    the  rat,   in    running   into  its  hole 


--^— 


Fig>.  IS  and  1!'.  -Tubc-trap>  I'loiii  Holicnliciin  {\  uat.  iti:c). 

strikes  the  plate  (a)  with  its  head,  and  is  then  caught  round 
the  body  by  the  pincers  (h).  It  is  better  to  place  two  such 
traps  back  to  back  in  a  hole.     For  the  smaller  species  the 


Fi-'.  50. 


Fig.  ol. 


tube-traps    from    Hohenheim    are   very  effective.    Figs.    48 
and  49. 

Ordinary  spring-traps  (Figs.  52  and  53)  are  more  useful  in 


Fig.  52. — (I  nal.  nizc). 

closed  rooms,  such  as  seed-stores,  but  when  concealed  by 
foliage,  etc.,  they  may  also  be  used  in  forest  nurseries,  carrots 
or  beetroot  forming  a  good  bait. 


MICE   AND    VOLES.  133 

For  seed-stores,  a  good  trap  for  mice  may  be  formed  by  a 
vessel  full  of  water,  over  the  edge  of  which  a  piece  of  wood  or 
platform  on  which  the  bait  is  fastened  is  balanced.    The  mice 


53. — (J  naf.  size). 


climb  up  a  slanting  piece  of  wood  on  to  this  platform,  and 
going  to  the  end  of  it  to  get  at  the  bait,  upset  the  balance  of 
the  platform  and  fall  into  the  water. 

r.  Smokiny-ouL 

Smoking-but  mice  is  not  possible  in  forests,  owing  to  the 
nature  of  their  holes  amongst  grass  and  dead  leaves,  and  also 
on  account  of  the  danger  of  firing  the  forest. 

tl.  Poisoning. 

Poisoning  is  the  most  effectual  method  of  destroying  mice. 

In  poisoning  mice  in  forests  there  is,  however,  great  danger 
of  killing  useful  animals,  such  as  weasels,  foxes  or  owls. 
Such  a  method  can  therefore  be  employed  only  after  every 
precaution  has  been  taken  against  danger  to  useful  animals, 
and  in  cases  where  the  mice  have  increased  enormously  in 
numbers. 

Poisoning  may  be  done  by  means  of  phosphorus,  arsenic, 
strychnine,  corrosive  sublimate,  or  carbonate  of  baryta.  Of 
these,  strychnine  is  the  most  effective.  Wheat,  oats  or  barley 
grains,  celery  or  radishes  may  be  used  with  the  poison,  the 
grahis  being  first  steeped  in  water,  and  then  placed  in  the 


134  PROTF/TIOX    AOATXST    ANIMALS. 

poisonous  solution ;  or  a  meal  prepared  and  the  poison  mixed 
up  with  it.     It  is  then  strewn  about  in  pieces  as  big  as  a  pea. 

In  order  as  far  as  possible  to  prevent  the  poisoning  of 
useful  animals,  the  poisoned  baits  must  not  be  placed  on  the 
bare  ground,  but  in  little  cylinders  of  wood  or  of  grass  sods, 
or  in  glazed  vessels  or  drain-pipes  about  IJ  inches  in 
diameter,  sufficient  to  allow  passage  to  a  mouse.  The  cylin- 
ders may  be  placed  on  the  ground  or  in  the  mouse-holes,  and 
must  be  inspected  regularly  in  order  to  observe  their  effects. 
Glazed  vessels  are  better  than  drain-pipes,  as  the  latter  let  in  • 
moisture. 

Phosphorus,  owing  to  oxidation,  soon  becomes  ineffectual  in 
damp  or  rainy  weather.  Arsenic  is  more  effective,  but  less 
rapid  in  its  action.  If  either  of  these  poisons  is  used,  the 
dead  mice  are  generally  found  lying  on  the  surface  of  the 
ground,  as  they  run  in  search  of  air  and  water  when  feeling 
the  pains  of  the  poisoning.  Strychnine  and  carbonate  of  baryta 
kill  the  mice  in  their  holes  after  severe  convulsions  ;  it  is 
better  to  change  the  bait  and  the  poison  from  time  to  time. 

A  pest  of  mice  rarely  lasts  more  than  2  or  3  years,  as  heavy 
rain,  frosts,  inundations  and  disease  soon  kill  them  by  thou- 
sands. It  would  not  however  be  right  to  wait  patiently  for 
such  an  event  to  occur,  for  by  timely  energetic  action  the 
damage  may  be  greatly  reduced. 

Attempts  were  made  (as  proposed  by  LoelHer)  in  1890,  to 
destroy  the  mice  which  were  infesting  the  fields  in  Thessaly, 
by  subjecting  them  to  a  parasitic  fungoid  disease  termed 
mouse-typhus ;  this  was  communicated  to  the  mice  by  pieces 
of  l)read  which  had  previously  been  soaked  in  water  con- 
taining spores  of  the  fungus.  The  results  in  this  case  were 
excellent,  and  it  has  since  been  adopted  on  agricultural  lands 
with  success  both  in  France .  and  Germany.  It  was  also 
successful  in  a  German  forest  in  1892-3,  on  15  acres,  at  a 
cost  of  5s.  G(/.  per  acre. 

4.   Treatmeut  of  Injured  PlautH. 

Broad-leaved  poles  and  saplings  which  have  been  badly 
gnawed  by  mice  should  lie  cut-back  in  tlie  spring  close  to  the 


BEAVERS  AND  PORCUPINES.  135 

ground,  below  the  injured  place,  sharp  instruments  being 
used  for  the  purpose,  so  that  they  may*send  up  new  shoots, 
If  the  plants  have  been  girdled  too  deeply  towards  the  roots, 
such  procedure  would  not  save  them,  but  of  course  the  dead 
poles  should  he  removed.  The  workmen  should  work  in  lines 
so  as  not  to  leave  out  any  injured  plants,  and  should  be 
properly  supervised.  If  the  cutting  is  done  too  late  in  the 
spring,  the  new  shoots^will  be  very  weak,  as  much  reserve 
material  then  passes  into  the  injured  stems,  and  is  conse- 
quently wasted  when  the  stems  are  cut  dow^n. 

Where  conifers  have  been  injured,  new  plants  must  be 
substituted  for  those  killed  by  mice. 

Beech  plants  that  have  been  gnawed  by  mice,  if  under  a 
foot  in  height,  may  be  saved  by  heaping  up  earth  above  the 
wounded  part  of  the  plants.  The  latter  then  send  out  fibrous 
roots  that  grow  down  into  the  soil  through  the  mounds.  This 
costs  about  Ir/.  per  100  plants. 


Section  VIII. — Beavers  and  Porcupines. 

The  beaver  is  an  animal  now  almost  extinct  in  Central 
Europe,  but  which  formerly  did  much  damage  to  forest  trees.* 
Beavers  {Castor  fiber,  L.)  are  still  pretty  numerous  in  Piussia 
and  Scandinavia,  in  North  America,  and  a  few,  still  exist  in 
France  in  the  Rhone  Valley.  They  fell  and  bark  many  species 
of  trees  up  to  9  inches  in  diameter,  chiefly  willows  and  poplars, 
but  also  ash,  oak,  and  elm  growing  near  streams.  The  trees 
felled  are  used  by  them  in  constructing  dams  to  protect  their 
dwellings,  and  they  also  eat  the  bark. 

The  porcupine  {Hystrix  leucura)  is  very  common  in  Indian 
forests,  and  girdles  saplings  and  poles  of  various  species, 
especially  of  I.eriuminoHae ;  it  does  much  damage  in  forest 
nurseries  by  burrowing,  and  by  devouring  seedlings  and 
vegetables.  It  should  be  excluded  by  strong  wire-netting, 
partly  buried  at  the  foot  of  a  fence,  as  in  the  case  of  rabbits. 
There  are  also  two  other  species  of  Ilystri.v  in  India. 

*  In  the  Himalayas,  the  black  bear  (^Urxun  tif/ef talus')  peels  the  bark  frona, 
ji»iaofi  cliwiHg  the  winter. 


136 


CHAPTER    TIT. 

PROTECTION    AGAINST    BIRDS.* 

SixrrioN  I.— GeneraiA  Account. 

The  birds  directly  hurtful  to  forests  belong  to  the  orders 
Galliuae  or  ganie-birds,  Cohnnhidae  or  pigeons,  and  Pasfseri- 
formae  or  perching  birds. 

1.  List  of  Hurtful  Birds. 

Grouse  {Tetraonvlae). 

Capercailzie  {Tetrao  urogcdlus,  L.). 
Black  game  {Tetrao  tetri.r,  L.). 
Hazel-grouse  {Bonasia  sdrcstris,  Brehm.). 

Piijeons  {Columhklae). 

Piing-dove  or  Wood  Pigeon  {Columha  ixdnmhus,  L.). 
Stock-dove  (C.  ocnas,  L.). 
Turtle-dove  {Turtur  communis,  L.). 

(Corridar). 

Jay  (Garndus  (ilaudarius,  Yieill.). 
Nutcracker  {Xncifraga  rari/ocatactcs,  Briss.). 

Finches  {Frintjilljdae) . 

Hawfinch  (Coccotliraustes  rnU/aris,  Briss,). 

Greenfinch  (('.  chloris,  Briss.). 

Chaftinch  {Friugilla  coclchs,  L.). 

jirambling  {F.  >nontifringilla,  L.). 

Siskin  (/''.  Sjnnns,  L.). 

Crossbill  {Lo.iia  curvirostra,  Gm,). 

Parrot  Crossbill  (L.  pitiiopsittacus,  Bchst.). 

*  The  scientific  names  arc  from  Yarrell's  '•  JJritisii  Jiirds,""  4tli  ed.,  1S.S2. 


GAME    BIRDS.  137 

A  few  other  species  of  small  singing  birds  are  hurtful  by 
eating  seeds  and  biting-off  buds,  such  as* — 

Bullfinch  (Pi/rrliula  eurojmca,  Vieill.). 
Mealy  Red-poll  {Linota  linaria,  L.). 
Eed-breast  {Kri/tliacus  ruhccuhi,  L.). 

Even  titmice  (Paridac)  do  some  harm,  and  woodpeckers 
(Pici)  make  holes  in  trees ;  these  families,  however,  do  more 
good  than  harm.  Birds  which  do  indirect  injury  by  killing 
other  useful  birds  will  be  described  further  on  under  the 
heading  Insects. 


2.  Damage  Done. 

Destructive  species  of  birds  eat-up  seeds  and  fruits,  bite-off 
buds,  young  shoots,  and  tender  seedlings,  but  are  generally 
useful  by  destroying  insects,  and  the  damage  done  by  birds  in 
forests  is  in  general  much  less  than  that  by  the  rodents  and 
deer  already  referred  to. 


3.  l^rotective  Rules. 

Delay  sowing  until  the  birds  hav^  paired,  and  cover  the 
seeds  well.  The  birds,  after  pairing,  no  longer  fly  about  in 
large  numbers,  and  they  kill  more  insects  than  before 
pairing,  both  for  themselves  and  for  their  young. 

The  seeds  may  be  steeped  in  red-lead  mixed  with  water,  or 
in  distilled  water,  lime-water,  or  very  dilute  acids,  so  as  to 
hasten  the  germination,  and  the  period  of  danger  from 
seed-eating  birds  may  thus  be  reduced  to  as  short  a  space  as 
possible. 

Sowings  may  be  covered  with  moss,  or  branches ;  in 
nurseries,  with  wire-netting  over  hoops  of  hazel,  willow,  etc. 

Scarecrows  may  be  used,  or  paper  feathers  on  string,  or 
stuffed  birds  of  prey. 

Watch  the  sowings  till  the  young  plants  are  large  enough 
to  be  out  of  danger. 

Fire  off  blank  cartridges,  or  shoot  the  birds. 


138  I'lJOTKX'TION    AOATNST    BIRDS. 

Section  II. — Tbe  Capercailzie  and  other  Grouse. 

1,  IhiJiuKje  Done. 

The  caiiorcaUzic,  which  frequents  extensive  tracts  of  moun- 
tain forests,  injures  nurseries  and  cultivations  of  conifers  in 
winter  and  spring  l)}-  biting-off  buds  and  young  shoots ;  in 
nurseries,  when  the  buds  of  the  plants  just  appear  above  the 
snow,  they  are  frequently  cut-off  in  great  numbers  by  these 
birds,  the  cock  being  more  injurious  than  the  hen.  Birch- 
buds  and  small  green  pine-cones  are  also  eaten.  The  caper- 
cailzie in  winter  frequents  old  woods  with  advance-growth,  and 
feeds  chiefly  on  the  needles  and  buds  of  old  spruce  trees,  but 
is  very  fond  of  the  buds  of  neighbouring  young  spruce.  In 
Scotland  it  prefers  Scots  pine.  In  the  spring  it  scratches 
the  soil  in  search  of  insects  and  worms. 

The  hlack-r/rouse  lives  in  mossy  heather-land,  and  does 
much  less  harm  .to  forests  than  the  capercailzie.  It  eats  the 
buds  and  inflorescence  of  birch  and  other  broad-leaved  species, 
and  attacks  buds  of  conifers  and  young  needles  of  the  larch, 
but  chiefly  nourishes  itself  with  berries  and  sn\all  shrubs 
(bin)eriy,  heather,  etc.),  and  keeps  itself  alive  in  winter  by 
eating  needles  of  old  spruce  trees.  It  goes  higher  in  the 
mountains  than  the  capercailzie. 

The  hazel-grouse  is  chiefly  found  in  broad-leaved  woods,  in 
the  Austrian  Alps  and  the  Russian  Baltic  Provinces  ;  it  feeds 
during  winter  on  birch  and  alder  buds  and  hazel-catkins.  In 
summer  it  chiefly  eats  berries,  but  does  less  harm  than  black 
game. 

PJicasants  scratch-up  sowings  in  the  forest,  and  nursery 
seed-beds. 


2.  Protective  Ihdes. 

Fence-in  nurseries  with  tall  thorny  bushes,  as  the 
capercailzie  is  very  shy,  and  avoids  places  so  protected. 

Branches  of  spruce,  etc.,  may  be  laid  over  sowings  tO' 
impede  the  movements  of  the  birds,  and  nursery  seed-beds, 
may  be  protected  with  wire-netting.     Buy  transplants. 


PIGEONS,    JAYS    AND    NUTCRACKERS.  139 

Section  III. — Pigeons  and  Doves. 
1.  Damage  Done. 

Wood-pigeons  and  doves  eat  u-p  forest  seeds,  especially  of 
spruce  and  Scots  pine,  also  buds,  catkins,  etc.  The  wood- 
pigeon  and  the  stock-dove  in  autumn  also  eat  acorns,  beech- 
mast  and  beech  cotyledons.  Turtle-doves  eat-up  seedlings, 
doing  most  damage  in  March,  and  from  April  to  October, 
when  they  often  alight  in  flocks  on  sowings. 

The  wood-pigeon,  the  largest  kind,  prefers  coniferous  forest 
(spruce) ;  the  stock-dove,  beech  and  mixed  forest  of  broad- 
leaved  and  coniferous  species ;  the  turtle-dove,  the  smallest 
kind,  lives  near  water  in  small  woods  among  fields  and 
meadows.  The  wood-pigeon  is  one  of  the  worst  enemies  to 
agriculture. 

2.  Protective  Rides. 

Those  already  given  under  the  general  heading  apply  here. 
Scarecrows  are  only  useful  at  first,  as  the  birds  soon  get  used 
to  them.  Strewing  seed-beds  with  spruce-needles  instead  of 
moss  protects  against  turtle-doves.  Shooting  is  best  done  at 
the  breeding  season  with  decoys,  or  over  salt.  Small  vessels 
containing  salted  clay,  anise,  hempseed  or  wheat  are  placed 
here  and  there  over  the  endangered  sowings,  and  the  pigeons 
flying  down  to  them  are  shot. 

Section  IV. — Jays  and  Nutcrackers. 

1.  ]>ania(ie  Done. 

The  jai/  is  extremely  destructive,  eating  acorns,  beech-nuts, 
walnuts,  hazel-nuts,  cherries  and  other  fruit,  digging-up  ger- 
minating beech-nuts  and  young  oaks  to  eat  their  cotyledons. 
It  also  destroys  the  young  and  eggs  of  other  birds,  and  even 
attacks  new-born  hares.  Once  it  has  discovered  a  sowing  of 
acorns,  it  will  completely  strip  the  bed.  In  acorn  sowings  in 
the  Forest  of  Dean  in  1899,  it  was  found  that,  when  the  turf 
was  broken  up  over  the  lines  of  sowings,  the  birds  picked  up 
most   of   the   acorns.      When   the   turf   was   taken   up   and 


140  PROTECTION    AOATNST    P.TRDS. 

replaced  over  the  acorns,  the  birds  did  not  recognise  the  place 
and  left  the  acorns  alone. 

At  the  same.time,  by  placing  acorns  and  beech-nuts  singly 
in  holes  in  the  ground,  which  it  after^Yards  forgets,  it  assists 
in  the  spread  of  the  oak  and  beech.  Of  more  value  is  its 
power  of  attacking  mice  and  insects,  but  the  good  done  is  less 
than  the  harm  effected  in  other  ways. 

The  nutrracker,  though  not  uncommon  in  the  spruce 
forests  of  the  Schwarzwald,  the  Bavarian  Alps,'  the  Tyrol  and 
Switzerland,  is  rare  in  Central  and  North  Germany,  and  in 
the  British  Isles.  Its  food  consists  of  hazel-nuts,  acorns,  and 
beech-mast,  and  especially  the  seeds  of  the  Cembran  pine,  of 
which  it  is  so  fond  as  to  pick  them  out  of  sowings  and  seed- 
beds in  the  very  presence  of  the  workmen  who  are  sowing  the 
seed.  It  also  destroys  the  eggs  and  young  of  useful  birds. 
This  extremely  restless  bird  also  sows  seeds,  and  in  this 
respect  is  more  useful  than  the  jay,  as  the  localities  it  prefers 
in  the  high  mountain  regions  are  those  where  planting  is 
extremely  costly,  and  any  assistance  to  man's  action  in 
rehoisemcnt  is  of  great  value. 

2.  Protective  liidcs. 

Cover  up  endangered  sowings  with  branches  of  thorn-bushes, 
immediately  after  sowing. 

Shoot  in  autumn,  when  jays  keep  flying  from  one  oak  to 
another.  Several  hundred  jays  are  thus  shot  every  year  in 
Epping  Forest. 

Section  V. — Finches  and  othek  Smalt-  Birds. 
1.  Damaf/e  Done. 

The  Jinir/iiicli,  rare  in  the  British  Isles,  is  very  fond  of 
fruits  and  seeds,  especially  those  of  the  hornbeam,  cherry, 
maples,  oaks,  beech,  alder,  elm  and  conifers.  The  traces  of 
its  activity  are  seen  in  the  remains  of  the  fruit  lying  under 
the  trees.  It  also  bites-off  buds.  In  general,  however,  the 
damage  done  by  this  bird  is  greater  in  gardens  and  orchards 
than  in  forests. 


FIXCHES    AND    OTHER    SMALL    BIRDS. 


14-1 


The  [irccnfincli  feeds  its  3'oung  on  soft  seeds,  and  by  thus 
destroying  countless  weeds  it  is  of  great  service  to  the 
gardener  and  agriculturist.  Later  on  in  the  year,  however, 
it  unites  in  large  flocks  with  the  chaffinch  and  other  finches 
and  small  birds,  and  they  may  do 
much  damage  to  sowings  in  the 
forest. 

The  chaffinch  is  extremely  fond 
of  coniferous  seeds,  those  of  the 
pine,  spruce,  and  larch,  and  bites 
off  young  cotyledons  of  conifers  as 
long  as  they  are  covered  by  the 
testa.  It  also  eats  beech-nuts, 
and  the  cotyledons  of  beech- 
seedlings. 

The  hramhling  appears  in  the 
late  autumn  and  winter  in  large 
flights  like  clouds,  and  attacks 
beech-nuts  and  coniferous  seeds. 
De  Montbeliard  states  that  in 
1705,  after  a  good  beech-mast 
year,  for  several  nights  600  dozens 
were  killed  near  the  Ehine,  and 
de  la  Fontaine  computes  a  flight 
of  bramblings  in  Luxemburg  in 
February,  1865,  at  60  millions. 
Stevenson  in  ;^[arch,  1865,  saw  a 
flock  of  bramblings  near  Slough 
which  passed  him  without  inter- 
mission for  35  minutes.  Both 
this  species  and  the  chaffinch  are 
extremely  destructive  to  coniferous 
and  beech  sowings,  and  to  natural 

reproduction  of  beech,  which  it  is  extremely  difficult  to  guard 
against  them. 

The  siskin  also  appears  in  great  numbers,  and  prefers  the 
seeds  of  the  alder,  but  also  attacks  sowings  of  birch,  spruce, 
silver-ffr,  larch,  and  other  conifers.  Something  may  be  said 
in  favour  of  the  ffnches  on  account  of  their  destruction  of 


Sprutc-Loue  attacked  by 
crossbill. 


142  I'KOTECTIOX    AGAINST    BIRDS. 

insects ;  the  hawfinch  frequently  catches  cockchafers  even 
when  they  are  on  the  wing,  and  then,  perching  on  a  twig, 
picks  them  to  pieces,  letting  the  hard  elytra  and  legs  fall  to 
the  ground. 

CrusiibiUs  are  extremely  ravenous,  and  appear  in  swarms 
when  there  are  good  seed-years  of  spruce  and  Scots  pine. 
They  live  on  the  seeds  and  berries  of  trees  of  several  species. 
They  bite  off  cones  by  the  base,  and  open  out  their  scales 
with  their  beaks  and  pull  out  the  seeds.  The  common  cross- 
bill can  only  open  spruce-cones,  but  the  parrot  crossbill  also 
attacks  pine-cones.  They  eat  mountain-ash  berries  when 
cones  are  scarce,  and  even  thistle-  and  dock-seed,  and  have 
been  seen  to  eat  beech-cotyledons.  They  do  some  compensa- 
tion by  eating  plant-lice. 

2.  Protective  littles. 

Blue  strings  may  be  placed  crosswise  over  sowings. 

Eed-lead  can  be  applied  to  the  seeds  in  the  following  manner : 
In  a  wide  vessel,  water  and  1  lb.  of  red-lead  are  stirred  to- 
gether, and  7  to  8  lbs.  of  spruce-seeds  mixed  up  with  it,  about 
1  lb.  at  a  time,  the  water  in  the  vessel  being  constantly  stirred 
until  the  seeds  will  take  up  no  more  of  the  lead.  The  seeds 
can  be  sown  at  once  without  drying.  This  costs  5d.  per  lb. 
of  seeds  for  labour  and  material.  Dilute  carbolic  acid  may 
also  be  applied  to  seeds,  as  already  mentioned.  Scarecrows 
are  of  very  little  use  against  finches. 

The  seed-beds  may  be  watched  during  the  dangerous  time, 
and  blank  cartridges  fired. 

A  good  plan  is  to  shoot  some  of  the  birds,  and  hang  the 
bodies  to  stakes  near  the  seed-bed. 

Cones  bitten  ofl"  and  dropped  by  crossbills  may  be  utilised 
to  secure  the  seeds  remaining  in  them. 


Section  YI. — Woodpeckers. 

The  question  whether  woodpeckers  are  useful  or  hurtful  to 
forests  has  been  a  subject  of  dispute,  and  will  be  here 
discussed. 


WOODPECKERS.  143 

1.  Jjist  of  Woodpeckers. 

In  Central  Europe  the  following  species  of  woodpeckers  are 
fDund : — 

Black  woodpecker  (Picas  martius,  L.). 
Greater  spotted  woodpecker  (Dcndrocopiis  major,  Koch). 
Intermediate  spotted  woodpecker  (D.  medins,  Koch). 
Lesser  spotted  woodpecker  {D.  minor,  Koch). 
White-backed  woodpecker  (i>.  leitconatus,  Bchst.). 
Three-toed  woodpecker  (Apternus  tridactijlm,  Gould). 
Grey  woodpecker  (Piciis  canns,  Gmel.). 
Green  woodpecker  (Picus  viridis,  L.). 

The  two  last  species  are  termed  ground-woodpeckers.  Of 
these  the  green  woodpecker  is  the  commonest  in  Britain,  and 
1).  major  and  minor  also  occur.  Nos.  2,  3,  and  7  are  said  to 
be  commonest  near  Giessen,  where  Hess  resides. 

2.  Opinions  of  rarioits  Authors. 

Opinions  regarding  the  utility  or  otherwise  of  woodpeckers 
from  a  forestry  point  of  view  have  varied  from  time  to 
time.  Towards  the  end  of  the  eighteenth  century  they  were 
considered  hurtful  by  pecking  holes  into  trees  which  were 
sometimes  sound  ones. 

In  Beckmann's"Handbuch  der  Jagdwissenschaft,"  pubhshed 
at  Nuremberg  in  1802,  this  opinion  was  adopted,  and  in  conse- 
quence a  reward  of  2(/.  per  head  was  offered  in  Germany  for 
their  destruction.  Bechstein  was  the  first,  in  1802,  to  consider 
them  useful,  and  Walther  in  1803 ;  also  Gloger  about  1860. 
Foresters  then  went  to  the  other  extreme,  considering  wood- 
peckers as  extremely  active  in  destroying  insects,  and  ignoring 
their  propensity  for  making  holes  in  trees.  Altum  in  his  "  Forst- 
zoologie"  reverted  to  the  former  opinion,  stating  that  wood- 
peckers were  practically  useless  against  dangerous  bark-beetles, 
but  attacked  the  larger  and  less  important  longicorn-beetles, 
and  that  they  themselves  did  considerable  damage  to  trees. 

Altum  wished,  however,  to  protect  woodpeckers  on  aesthetic 
grounds,  because  they  enliven  the  forest  and  please  the  eye. 
Judeich  follows  Altum's  views  to  a  certain  extent.     Konig, 


144 


PROTECTION   AGAINST    BIRDS. 


Dobner,  Vogt,  the  brothers  Miiller,  Taschenberg,  Borggreve, 
Korclliiiger  and  others  consider  tluit  the  utility  of  woodpeckers 
outweighs  the  harm  they  may  do,  and  Hess  expresses  himself 


Fig.  55  -  Scots  piuc  coues  fixed 
into  a  tree  by  woodpecker 
(\  nat.  size). 


Fig.  o(j, — Spruce  coue  attacked  by 
woodpecker. 


as  of  the  same  opinion,  from  the  most  recent  observations  on 
the  subject. 

3.  Damage  done  hi  Wood])eckers. 

Woodpeckers  eat  forest-seeds,  peck  wounds  in  saplings,  and 
holes  in  sound  poles  and  trees  ;  they  girdle  sound  trees  and 
destroy  telegraph-poles  and  wooden  rouf-shingles. 


WOODPECKERS.  145 

a.  Dostrurlion  of  Seeds. 
Dendyocopus  major  alone  -of  the  woodpeckers  eats  large 
quantities  of  coniferous  seeds.  It 
wedges  the  cones,  which  it  has 
plucked  from  trees,  in  a  cleft  in  the 
hark,  or  in  an  angle  hetween  a  stem 
and  a  branch,  and  opens  them  out 
and  removes  the  seeds  with  its  bill. 
We  can  distinguish  between  the 
action  of  the  woodpecker  and  cross- 
bill in  this  respect.  Frequently  the 
ground  under  a  tree  is  covered  with 
opencd-out  cones.  Also  walnuts, 
hazel-nuts,  acorns,  and  other  fruits     ^..     r-,    rc„„„  ..t  a.^^  „•„ 

'  '  rig;.  07. — Cone  or  hcots  pino 

are  eaten  by  the   great  woodpecker.         attacked  by  woodpecker. 

The  damage   done  is   not,  however, 

very  serious,  as  W'oodpeckers  are  solitary  birds. 

h.   ]''crlcin(i  Hole>i  in  sound  Trees. 

The  black  and  the  great  woodpecker  do  most  of  this  damage, 
and  attack  isolated  trees  and  saplings.  The  woodpecker  also 
attacks  freshly  planted  saplings  of  oak,  beech,  acacia,  exotics, 
etc.,  and  the  reason  for  its  doing  so  is  not  very  clear;  in 
coniferous  woods  it  may  thus  free  the  beak  from  resin  derived 
from  the  cones  it  has  been  attacking. 

Older  trees  are  also  attacked,  such  as  avenuje-trees  (poplars, 
limes),  oaks  occurring  in  coniferous  forests,  boundary  trees,  etc. 
Most  of  this  damage  is  done  during  spring  and  early  summer 
but  it  is  too  rare  to  be  of  any  practical  importance. 

c.  (jirdll7iii  Trees. 
The  same  two  woodpeckers,  while  hanging  to  the  trunk  by 
their  feet  with  the  support  of  their  tail  feathers,  encircle  trees 
with  rings  of  holes  arranged  horizontally.  A  callus  forms  at 
each  hole,  but  is  pecked  at  again  and  again  until  quite  a  ledge 
has  been  made  round  the  tree.  Trees  may  sometimes  be  seen 
with  several  such  ledges,  one  above  the  other,  resembling  the 
rings  on  bamboos.  The  reason  for  these  attacks  on  sound 
trees  has  not  yet  been  discovered  (Fig.  58). 

F.P.  L 


14^  PROTECTION    AGAINST    BIRDS. 

(J.  Di'sfrwfion  of  Tchgraph-Posls. 
The  great  woodpecker  as  well  as  the 
black  and  green  woodpeckers  share 
in  this  damage.  Attacks  have  been 
observed  both  on  coniferous  or  oaken 
posts,  whether  kyanised,  or  not,  and 
generally  commence  at  an  old  screw- 
hole.  In  1881,  the  Director  of  Post- 
Offices  for  the  German  Empire  issued 
a  circular  order  that  all  holes  in 
telegraph-posts  should  be  filled  with 
wooden  plugs,  and  that  holes  freshly 
made  by  woodpeckers  should  be  at  once 
smeared  with  tar.  Injuries  done  by 
woodpeckers  to  the  wooden  shingle 
roofs  of  forest  lodges  and  other  solitary 
houses  have  been  noticed,  but  are  rare 
and  unimportant. 

'/'Mfll^l  4.    VtiUti)  of  Woodpeckers, 

a.  JJe.sf rue/ion  of  Inserts. 
The  injurious  insects,  which  wood- 
peckers devour,  live  either  in  or  on  the 
surface  of  the  soil,  or  in  the  wood  or 
bark  of  trees,  and  the  latter  kinds  are 
preferred. 

Woodpeckers  chiefly  seek  animal  food 
from  April  till  late  summer.  They 
capture  cockchafers,  pick  grubs  from 
fruit,  and  eat  the  pupae  of  moths  and 
sawflies;  they  dig  into  ant-hills,  con- 
suming numbers  of  ants,  which  are 
said  by  Yarrell  to  be  the  chief  summer 
by  woo"dpec"kei\  food  of  the  green  woodpecker,  and  they 

a  Ring,  with  bark  still  peek  holes  into  the  ground  in  search  of 
h  Dittrb"rk°balf  removed,  cockchafer  grubs,  wire-worms,  etc.  For 
c  Ditto,  bark  eutirely  re-  the  most  part,  liowever,  they  hunt  on 
trees  for  weevils,  bark-beetles,  longicorn- 
beetles  and  their  grubs,  sawfly  larvae,  gall-insects,  spiders,  etc. 


^kV^ 


Fiy.  Ob. — Scuts  piue  girdled 


WOODPFX'KER.S. 


147 


Fig.  59  shows  a  Scots  pine  stump  attacked  by  woodpeckers 
in  search  of  insects. 

The  tongue  of  woodpeckers,  owing  to  its  construction,  is  ex- 
tremely useful  in  the  search  for  insects  ;  it  is  very  long  and  thin, 
and  is  furnished  near  the  tip  with  a  few  stiff  barbs  pointing  back- 


Fi.!^.  ■')!'.  -  Scots  jiiiio  stump  visited  by  \voi)ilpei.k(r<. 
(Jftcr  Altuni.) 

wards.  The  cornua  of  the  hyoid  bones,  which  support  it,  curve 
round  the  back  of  the  head  to  its  upper  surface,  terminating  in 
a  cavity  in  the  bones  of  the  beak,  and  their  mobihty  and  great 
length  allow  the  tongue  to  be  freely  extended.     The  woodpecker 


1/2  Fig.  60 

a  Head  of  woodpecker  QPicus  canns,  Gmel). 
//  Cornua  of  the  hyoid  bone.  x 
n  Nostril. 

0  Ear.  z 

s  Salivary  glaud. 


h  Tip  of  tongue  with  barbed  hairs. 
Opening  in  the  maxilla  for 

the  cornua. 
ron<rue. 


darts  its  tongue  into  cracks  in  the  bark,  using  the  barbs  for 
detaching  the  insects,  which  are  captured  by  adhesion  to  the 
slimy  surface.     The  spotted  and  ground  woodpeckers  hunt  in 

L  2 


148  PROTECTIOX   AGAINST    BIRDS. 

this  manner  more  or  less  throughout  the  year,  the  former 
chiefly  on  trees,  and  the  hatter  more  on  the  surface  of  the 
ground. 

Woodpeckers  detect  insects  by  the  senses  of  sight,  smell  and 
sound;  it  is  not  yet  decided  \Vhicli  of  these  is  predominant.  It 
cannot  be  denied  that  they  prefer  the  large  but  less  harmful 
larvae  of  Ceramhycidae,  Cossus  and  Sirex,  to  the  minute  larvae 
of  weevils  and  bark-beetles,  but  repeated  observation  shows 
that  they  are  also  keen  hunters  of  the  latter.  Amongst  the 
most  hurtful  species  which  they  destroy  may  be  mentioned 
Pissodes  pini,  L.,  I\  notatus,  Fabr.,  Mi/dopliilns  piniperda,  L., 
and  Hylastes  imlliatus,  Gyll.  The  damage  done  by  the  black 
and  ground  woodpeckers  to  ant-hills  may  indeed  be  classed  as 
injury  to  the  forests,  to  which  ants  are  useful,  but  living  larvae 
of  parasitic  beetles  are,  when  present,  often  preferred  to  ants 
by  the  woodpeckers. 

h.  Nidijiciition  in  7'rees. 
Woodpeckers  cannot  make  nest-holes  in  trees  without 
injuring  them,  but  this  is  done  chiefly  in  the  case  of  soft- 
wooded  species,  the  aspen,  lime,  etc.,  or  in  rotten  old  hard- 
woods. The  damage  done  is  not  great,  and  the  holes  are 
subsequently  used  for  breeding  by  several  useful  birds, 
starlings,  titmice,  and  flycatchers,  the  former  frequently 
driving  the  woodpeckers  from  a  new  hole  they  have  just  made, 
in  order  to  build  their  own  nest  there. 

5.  SnuiDuiri/. 

The  result  of  investigations  into  the  utility  of  woodpeckers 
tends  to  show  that  these  birds  by  their  activity  in  the  destruc- 
tion of  insects  play  a  most  useful  part  in  Nature,  and  should 
therefore  be  protected  by  foresters.  Hess  holds  the  same 
views  as  Borggreve,  that  all  useful  birds  tend  to  prevent  an 
undue  preponderance  of  insects,  keeping  their  numbers  more 
or  less  normal  in  ordinary  years.  In  case  of  a  great  insect 
calamity,  however,  the  action  of  birds  is  inadequate  to  protect 
the  forests ;  ichneumon-flies  and  fungoid  diseases  eventually 
put  a  stop  to  the  plague. 


14.9 


CHAPTER  IV. 

FOREST    INSECTS.       GENERAL    ACCOUNT. 

Section  I. — Classification. 

Entomology  is  the  science  dealing  with  iilsects,  which  belong 
to  the  division  of  the  animal  kingdom  termed  Arthropoda, 
including  all  animals  the  bodies  of  which  are  bilaterally  sym- 
metrical and  composed  of  segments,  that  is,  of  successive 
transverse  divisions  which  present  a  more  or  less  complete 
recurrence  of  structural  features,  and  which  have  articulated 
appendages.  The  body  and  its  appendages  possess  a  hardened 
exterior,  formed  of  a  substance  termed  cldtin,  'similar  in 
character  to,  but  not  identical  with,  horn,  and  the  muscles 
are  internal,  and  attached  to  the  external  skeleton.  The  sym- 
metry of  the  successive  segmients  is  not  complete  from  end  to 
end  of  the  body,  and  is  more  evident  in  the  body- walls  and 
their  appendages,  than  in  the  viscera.  The  segments  are 
aggregated  into  deiinite  groups,  the  components  of  which  are 
more  nearly  related  to  each  other,  particularly  in  the  structure 
of  their  appendages  than  to  the  segments  of  the  other  groups. 
This  form  of  segmentation  is  termed  lictcronomous.  The 
nervous  system  consists  of  a  double  chain  of  ganglia  placed 
along  the  ventral  surface  of  the  body,  connected  with  each 
other  longitudinally  and  transversely  by  nerve-commissures, 
and  traversed  anteriorly  by  the  digestive  system  ;  the  vascular 
system  is  dorsal.     Eespiration  is  effected  in  various  ways. 

The  four  great  Classes  of  Arthropoda  are  : — 

1.  Crustacea:  respiring  by  branchiae  or  gills,  or  by  the 
general  surface  of  the  body ;  with  two  pairs  of  antennae  and 
more  than  eight  locomotive  appendages,  the  latter  forked  or 
biramous.     Crabs,  lobsters,  shrimps,  woodlice,  etc. 

2.  Avachnida :  respiring  in  various  ways,  usually  air- 
breathing  ;  head  and  thorax  united  ;  with  two  pairs  of  jaws 


150  PROTECTION  AOAIN.ST  INSECTS. 

and  four   pcairs  of  legs ;    abdomen    destitute    of    limbs ;     no 
antennae.     Scorpions,  spiders,  and  mites. 

3.  Mi/riapoda:  respiring  by  tracheae,  or  involutions  of  the 
integument ;  head  distinct,  remainder  of  the  body  formed  of 
nearly  similar  segments  ;  one  pair  of  antennae  ;  three  pairs  of 
jaws  and  numerous  legs.     Centipedes,  millepedes. 

4.  Insecta:  respiring  by  tracheae;  head,  thorax,  and 
abdomen  distinct,  one  pair  of  antennae ;  three  pairs  of  legs 
on  the  thorax ;  abdomen  without  well-developed  limbs ; 
generally  with  two  pairs  of  wings  on  the  thorax.     Insects. 

A  knowledge  of  the  general  anatomy  of  insects,  and  of  the 
terms  used  in  the  present  book  i\\  describing  the  different 
species,  is  presupposed. 

Insects  as  a  general  rule  before  attaining  maturity  pass 
through  a  series  of  changes  termed  metamorphoses. 

The  different  stages  of  their  life  consist  of  the  ('(jcf,  larva, 
impa,  and  imago  or  perfect  insect.  Some  insects,  such  as 
parasitic  lice,  do  not  appear  to  undergo  any  metamorphosis, 
the  young  on  hatching-out  resembling  their  parents  in  all 
respects  except  in  size,  although  they  may  moult,  or  shed  their 
skins  frequently ;  they  are  known  as  ametahoUc  insects. 

The  larval  stage  is  essentially  the  stage  of  growth  and  of 
active  feeding.  The  larva  undergoes  several  moults  or  calysea, 
never  possesses  wings  and  is  incapable  of  reproduction. 

The  larvae  of  insects  may  be  destitute  of  legs,  as  in  the  case 
of  fly  maggots,  or  they  may  have  three  pairs  of  true  legs,  on 
the  first  three  segments  after  the  head,  as  in  the  cockchafer 
grub,  or  in  addition  to  these,  two,  five,  six,  or  seven  pairs  of 
clasping  feet,  or  prolegs  attached  to  the  abdominal  segments, 
of  which  the  pair  on  the  last  segment  are  known  as  the  anal 
prolvgs  or  claspcrs.  The  larvae  of  Lepidoptera  are  termed 
caterpillars. 

The  pupa  of  insects  is  usually  inactive,  and  is  protected  by 
its  dried  and  hardened  skin ;  frequently,  as  in  spinning 
Lepidoptera,  it  is  surrounded  by  a  protective  case  termed  a 
cocoon,  and  constructed  by  the  larva. 

In  the  case  of  certain  insects,  as  grasshoppers,  the  pupa 
differs  from  the  larva  only  in  having  rudiments  of  wings;  it 
is  still  active  and  feeds,  and  is  termed  a  nymph.     Such  a  pupa 


CLASSIFICATION.  tbl 

is  converted  into  the  iiiiago  b}^  the  liberation;  of  its  wings  at 
the  last  moult. 

The  insects  which  undergo  metamorphosis  are  consequently 
divided  into  metabolic  insects,  or  insects  with  complete  meta- 
morphosis, in  which  the  pupa  is  quiescent  and  does  not  feed, 
and  in  which  the  greatest  weight  and  bulk  is  attained  at  the 
end  of  the  larval  stage ;  and  into  hcmi-metaholic  insects,  in 
which  there  is  an  active  iii/inph  and  the  imdf/o  is  the  bulkiest 
and  heaviest  form.  Metabolic  insects  form  95  per  cent,  of  the 
whole  class. 

Insects  may  be  grouped  either  according  to  the  structure  of 
their  bodies,  or  their  mode  of  life,  and  Entomology  uses  the 
former  of  these  characters  in  their  classification,  but  in  Forest 
Protection  it  is  of  greater  convenience  to  study  the  latter. 

Much  difference  of  opinion  has  existed  regarding  the  classifi- 
cation of  insects.  The  simplest  method,  based  on  the  systems 
of  Linnaeus  and  Fabricius  recognises  seven  Orders.  The 
former  naturalist  relied  principally  on  the  structure  of  wings 
in  distinguishing  the  different  orders  of  insects,  and  the  latter 
on  the  parts  forming  the  insect's  mouth.  The  Orders  may 
also  be  arranged,  according  to  the  degree  of  completeness  of 
their  metamorphoses,  in  two  groups  containing  the  metabolic 
and  ametabolic  insects  respectively.  Though  the  degree  of 
metamorphosis  is  of  the  first  importance  as  a  guide  to  the 
systematic  position  of  an  insect,  it  is  not,  when  taken  alone, 
of  the  highest  value  in  classification,  as  it  cannot  be  decided 
by  mere  observation  of  any  particular  insect,  without  study  of 
its  life-history. 

Certain  writers  who  have  attached  great  weight  to  structural 
differences,  particularly  of  the  wings,  have  increased  the 
number  of  Orders  to  thirteen  (West wood)  or  sixteen  (Packard). 
The  groups  which  have  been  raised  to  the  rank  of  additional 
Orders  are  of  minor  importance,  and  contain  as  a  rule  a  small 
number  of  aberrant  forms.  In  the  present  work,  the  broadest 
and  most  generally-received  classification  will  be  followed,  in 
which  the  Insects  are  divided  into  seven  Orders,  characterised 
as  follows  : — 

1.  Orthoptera  :  with  biting  mouth-parts,  a  free  prothorax, 
and  incomplete  metamorphosis.    Cockroaches,  crickets,  locusts, 


152  PROTECTION    AOAINST    IXSIOCTS. 

termites  or  wliite  ants,  and  dragon-flies,  are  examples  of  this 
order,  the  two  latter  belonging  to  a  sub-order  termed  Orthoptera 
2)seudo-neui'optera.  In  this  sub-order  the  head  is  horizontal 
and  the  wings  membranous  in  texture ;  in  the  true  Orthoptera 
(0.  (/eniiina)  the  head  is  vertical  and  the  wings  are  stronger 
and  of  a  more  leathery  consistency. 

2.  Ncurojytera :  with  biting  mouth-parts,  a  free  prothorax, 
two  pairs  of  membranous  richly-veined  wings,  and  complete 
metamorphosis.  Lace-winged  flies  {CJinjsopa  and  Ilemcrohius) 
are  examples. 

3.  Culeoptcra:  with  biting  mouth-parts,  free  and  strongl}'- 
developed  prothorax  ;  two  pairs  of  wings,  of  which  the  upper 
are  horny,  protective  and  not  used  for  flight,  being  known  as 
wing-cases  or  elytra,  and  the  lower  membranous ;  complete 
metamorphosis.  It  includes  all  beetles,  of  which  the  common 
cockchafer  may  be  taken  as  a  type. 

4.  Ilymenuptera :  with  biting,  or  biting  and  partly  suctorial 
mouth-parts ;  the  prothorax  fused  at  least  dorsally  with  the 
mesothorax ;  two  pairs  of  membranous  wings  with  com- 
paratively few  veins,  sometimes  apterous  ;  with  complete 
metamorphosis.     Examples:  bees,  wasps,  ants,  and  sawflies. 

5.  Lcpidoptera :  with  suctorial  mouth-parts,  the  prothorax 
annular  and  fused  with  the  mesothorax,  two  pairs  of  mem- 
branous wings  covered  completely  or  partially  with  scales; 
complete  metamorphosis.  The  butterflies  and  moths  belong 
to  this  order. 

6.  Dipteni :  with  sucking  mouth-parts,  an  annular  prothorax 
fused  with  the  mesothorax,  one  pair  of  well-developed  mem- 
branous fore-wings,  the  hind-wings  rudimentary  and  reduced 
to  small  stalked  knobs,  forming  the  so-called  jwiscrs.  Com- 
plete metamorphosis.     This  order  includes  all  flies. 

7.  llcmiptcra  :  with  sucking  mouth-parts,  a  free  prothorax, 
and  incomplete  metamorphosis.  Bugs,  aphides,  and  scale 
insects  belong  to  this  order. 

Forest  Protection  deals  with  forest  insects  only,  namely, 
those  insects  that  aflect  forest  plants  either  prejudicially,  or 
henejicially,  and  this  either  directly,  or  indirectly.  Injurious 
insects  have  a  direct  influence  on  forest  plants  by  biting, 
sucking,   or  killing  them,      lioth  injurious  or  useful    insects 


DISTRIBUTION   OF   INSECTS.  153 

may  be  killed  by  other  insects,  which  are  thus  indirectly  useful 
or  injurious. 

The  vast  importance  to  foresters  of  forest  insects,  the 
enormous  amount  of  damage  which  these  small  but  mighty 
members  of  Nature's  household  can  effect,  combined  with  the 
fact  that,  owing  to  their  small  size  and  obscure  mode  of  life, 
they  escape  observation  much  more  readily  than  injurious 
vertebrates,  render  it  necessary  to  spend  more  time  on  their 
study. 

A  full  account  of  the  anatomy  of  insects  will  not  be  attempted 
here,  and  the  works  of  Altum,  Eatzeburg,  etc.,  may  be  referred 
to,  the  most  comprehensive  work  on  forest  insects  being  the 
revision  of  the  8th  edition  of  Eatzeburg's  book  by  Judeich 
and  Nitsche.* 

The  following  works  also  merit  attention  :  5th  Eeport  of  the 
United  States  Entomological  Commission,  "Forest  Insects," 
by  Dr.  A.  S.  Packard,  Washington,  1890;  "  Manual  of  Injurious 
Insects,"  by  Miss  Ormerod,  London,  Messrs.  Simpkin,  Marshall 
&  Co.,  1890;  "Indian  Forest  Zoology,"  by  E.  C.  Cotes, 
Calcutta,  1893;  and  "Injurious  Insects  in  Indian  Forests," 
by  E.  P.  Stebbing,  now  being  published  in  parts.  "  Leitfaden 
der  Forstinsectenkunde,"  by  Dr.  Nusslin  (Paul  Parey,  Berlin), 
an  excellent  work  for  students.  1905.  Mr.  A.  T.  Gillanders 
is  now  bringing  out  a  comprehensive  work  on  Forest 
Entomology. 

Section  II. — Distribution  of  Insects. 

The  geographical  distribution  of  insects  may  be  considered 
both  hurizontally  and  vertically. 

As  regards  the  ]iurizo)ital  distribution  of  insects,  the  local 
mobility  or  the  wandering  nature  of  many  species  precludes 
the  possibility  of  defining  zones  similar  to  those  laid  down  for 
plants.  It  may  be  stated  roughly  that  there  are,  in  Central 
Europe,  fewer  species  in  the  north  and  east  than  in  the  south 
and  west.  Beetles,  however,  form  an  exception  to  this  rule, 
being  more  abundant  in  the  north  and  east.  As  instances  of 
special  areas  for  certain  insects  may  be  quoted :  The  ash-cicada, 

•  "  Lebrbuch  (ler  Mitteleuropaischen  Forstinsektenkunde  "  (alsacbte  Auflage 
\ou  Ratzeburg's  Die  Waklvenlerber  und  ihre  Feindc)  berausgcgebcu  von 
Dr.  J.  F.  Judeich  u.  Dr.  H.  Nitsche.     Vienna  :  Eduard  Hlilzel.  1S8'J— 95. 


154  PROTECTION    AfiAINST    INSECTS. 

which  does  not  occur  north  of  the  river  Main  ;  the  oak  proces- 
sion moth  is  commonest  in  north  and  east  Germany.  The 
character  of  the  insect  fauna  is,  however,  generally  similar 
over  the  whole  of  the  Palaearctic  region,  which  includes 
Europe,  the  northern  coasts  of  Africa,  and  Asia  north  of  the 
great  mountain  chains  that  cross  it  from  east  to  west.  The 
numher  of  species  extending  over  the  whole  of  this  region  is 
comparatively  small,  and  there  are  no  zones  in  it  in  which 
the  character  of  the  insect  inhabitants  is  abruptly  changed. 
As  compared  with  continental  regions  under  similar  climatic " 
conditions,  the  insect  fauna  of  the  British  Isles  is  poor. 

As  regards  altitude,  the  distribution  of  insects  depends  on 
that  of  the  trees  and  shrubs  on  which  they  feed,  and  also  on 
locality  and  climate.  Most  insects  prefer  the  warmer  plains 
and  hilly  districts,  especially  with  a  sandy  soil,  where  beetles 
tlirive.  Soils  naturally  poor  and  those  impoverished  by 
removal  of  litter,  sunny  aspects,  frost-hollows,  and  stunted 
vegetation  are  natural  breeding-grounds  for  insects,  and 
require  the  most  careful  supervision  on  the  part  of  the 
forester.  The  number  of  species  and  of  individuals  alike 
diminishes  with  increasing  altitude ;  this  is  especially  the  case 
with  Lepidoptera,  which  are  most  dependent  on  climatic  con- 
ditions, but  beetles  are  found  at  a  considerable  elevation  in 
mountains.  Certain  species  of  weevils  and  bark-beetles  may 
be  considered  as  mountain  insects,  sucli  as  Otiorrluinchus 
niger,  Fabr.,  Tomkus  cemhrae,  Heer,  Hi/Iastcs  c/labratus,  Zett. 
Even  species  of  Chermes  are  found  at  elevations  of  between 
3,000  and  3,600  feet. 

Insects,  especially  beetles,  can  support  severe  winters. 
This  was  proved  in  1870-1,  1879-80,  the  summers  that 
succeeded  these  hard  winters  being  rich  in  insects.  Their 
horny  elytra  or  wing-coverings  protect  them,  and  instinct 
impels  them  to  creep  under  roots  and  into  cracks  in  the  bark 
of  trees,  or  under  moss  or  dead  leaves  for  protection  against 
the  weather,  or  to  burrow  underground.  Moreover,  as  their 
enemies,  moles  and  insectivorous  birds,  cannot  touch  them 
when  snow  or  frost  covers  the  ground,  and  are  themselves  killed 
in  very  severe  winters,  such  weather  is  really  favourable  to 
insect  life.     A  warm  winter,  which  is  usually  accompanied  with 


LIFE-HISTORY.  155 

much  moisture,  is  very   destructive   to   hibernating    insects, 
esj^ecially  hairy  larvae,  which  suffer  from  fungoid  diseases. 

Insects'  eggs  and  pupae  are  ahuost  insensible  to  cold. 
Hairless  larvae  are  most  sensitive,  especially  at  moulting 
periods.  Cold  damp  weather  and  cutting  winds  will  then  kill 
them  off  in  myriads.  Storms  blow  larvae  by  thousands  from 
the  crowns  of  trees.  Uniformly  warm  years  without  heavy 
rains  therefore  tend  to  produce  great  swarms  of  insects.  Very 
dry  summers  greatly  reduce  the  food  of  some  insects  and 
consequently  their  numbers. 


Section  III. — Life-Histoky. 
1.  Generative  Periods. 

Insects  are  distinguished  from  more  highly  organised  crea- 
tures by  having  generally  a  definite  limitation  to  their  duration 
of  life.  The  time  which  elapses  between  the  egg  and  the 
fresh  production  of  eggs  is  termed  a  generation.  These 
may  be  single  or  annual,  multiple,  biennial  or  plurennial. 

A  single  generation  occurs  when  an  insect  goes  through  all 
its  stages  within  twelve  months  (not,  however,  within  a  single 
calendar  year),  and  is  by  far  the  commonest.  Thus,  nearly  all 
I.epidoptera  have  one  generation  in  the  year.  A  few  Lepidop- 
tera  have  more  than  one  brood  in  the  year,  and,  still  more 
rarely,  the  life  of  an  individual  species  may  extend  through  two 
years,  as  Tortrlr  resinella,  L.,  or  even  longer. 

In  the  case  of  a  vudtiple  generation,  several  broods  are  pro- 
duced during  twelve  months,  so  that  the  respective  stages, 
eggs  or  larvffi,  of  the  same  species  may  be  found  in  different 
months.  A  double  generation  is  here  commonest,  as,  for 
instance,  in  the  case  of  many  bark-beetles  and  sawflies. 
Many  plant-lice  produce  five  or  more  generations  in  a  single 
summer,  and  the  Bengal  multivoltine  silkworm  completes  a 
generation  every  month,  except  during  the  period  from 
November  to  February.  Three  broods  are  sometimes  pro- 
duced within  two  years,  for  instance,  by  Tomicus  hidentatus, 
Hbst.,  but  such  cases  are  rare.  A  plurennial  generation 
denotes  that  the  insect  takes  more  than  one  year  for  its  full 


156  PROTECTION   AGAINST   INSECTS. 

developiuent,  for  example,  two  years  in  the  case  of  longicorn 
beetles  and  Sirex,  and  three  or  four  years  for  the  cockcliafer. 

Of  the  several  stages  of  the  insect,  that  in  which  it  hiber- 
nates lasts  the  longest,  and  is  generally  the  larval  stage.  The 
egg  and  pupal  stages  usually  last  for  about  two  to  four  weeks 
unless  they  happen  to  be  the  hibernating  stage,  and  eggs  laid 
after  Midsummer  do  not  generally  hatch  out  till  the  succeeding 
year.  As  a  rule,  the  imago  stage  is  the  least  long-lived  ;  but 
with  beetles  this  is  not  the  case,  as  the  imagos  very  frequently 
hibernate.  Many  IIi/mcnojHcra  are  long-lived  insects  ;  bees, 
for  example,  live  four  or  five  years. 

F.  Riihl,  of  Zurich,*  has  observed  the  life-period  of  a 
few  beetles  in  their  various  stages  :  eggs,  5-44  days  ;  larvae, 
47-1640  days  (many  longicorn  larvae  live  longer) ;  pupae,  8-39 
days ;  beetles,  3-GO  days.  As  a  rule,  insects  with  fully 
developed  sexual  organs  live  for  a  short  time  only,  while 
unsexual  insects  live  longer. 

Many  families  of  insects,  for  instance,  bark-beetles,  have 
irregular  broods  ;  the  state  of  the  weather,  and  the  quantity  and 
quality  of  their  food  may  cause  the  develoi)ment  of  one,  two, 
or  even  three  broods  in  a  year.  On  the  other  hand,  certain 
circumstances,  such  as  unfavourable  weather,  want  of  oppor- 
tunity for  pairing  or  for  laying  eggs,  may  not  unfrequently 
cause  delay  in  a  brood.  Thus,  for  instance,  a  brood  of  the 
pine  sawfly  {Lophyriis  pmi,  L.)  has  been  known  to  extend 
over  1^  to  2  years,  instead  of  there  being  one  or  two  broods  in 
the  same  year. 

2.  Habitat. 

The  habitat  of  insects  varies  according  to  their  state  of 
development  and  the  season  of  the  year.  They  are  sometimes 
found  on  or  under  the  surface  of  the  ground,  or  on  woody  or 
herbaceous  plants.  They  generally  hibernate  under  the  soil- 
covering,  or  inside  the  bark  of  trees.  As  a  rule,  all  insects 
live  near  the  material  on  which  they  feed,  but  many  wander 
far,  sometimes  against  their  will,  as  when  they  are  blown  into 
the  sea  by  storms  of  wind.  They  generally  endeavour  to  return 
to  their  former  abode,  as  in  the  case  of  bees  and  ants. 

Examples   of   insects  that  have  been  imported  to  Europe 

*  "  Ccntialbliitt  fur  ilas  Ges.  Forbtwcsen,"  1888,  p.  156. 


LIFE-HISTORY.  157 

are  :  The  longicorn  beetle,  Gracilia  pygmaea,  Fabr.,  which  came 
to  Germany  in  the  hoops  of  casks  made  of  willows  or  oak. 
Species  of  Li/ctus  were  imported  in  Australian  wood.  The 
destructive  Colorado  beetle  (Doryphora  deccmlincata)  came 
from  America  with  a  cargo  of  potatoes.  The  phylloxera 
{P.  vastatrix,  Planch)  on  American  vines. 

3.  Mobility. 

The  mode  and  degree  of  rapidity  with  which  insects  move 
may  be  usually  inferred  from  the  structure  of  their  organs  of 
locomotion.  Some  insects  have  legs  for  running,  as  ground- 
beetles  ;  for  jumping,  as  fleas  ;  for  digging,  as  crickets  ;  for 
swimming,  as  water-beetles. 

The  imagos  run  or  fly  ;  their  course  being  rapid  {Carahns), 
or  slow  {Ceramhyx) ;  their  flight  is  either  fast  (Bomhus),  slow 
{Mdolonth<i),  irresolute  (Papilio),  or  hovering  (Syiplius)  ;  ex- 
tended {Sphyux  pinastri,  L.),  or  short  {Gryllns).  The  flight 
of  the  ?  *  is  heavier  than  that  of  the  3  ,  especially  when  she 
is  laden  with  eggs. 

The  mobility  of  the  larvae  depends  largely  on  the  number  of 
their  legs  (6,  8,  10,  16,  18,  22),  all  but  six  of  which  are  soft 
and  fleshy  prolegs.  Many  lepidopterous  caterpillars  assist 
their  movements  by  spinning  threads,  such  as  those  of  many 
Bombyces,  Geometers  and  Tortrices  {e.g.  Tortrix  viridana,  L.) 

4.  Food. 

Metabolic  insects  feed  only  as  larvaB  and  imagos,  and  chiefly 
in  the  former  state.  Thus,  the  food  of  butterflies  and  moths 
is  limited  to  the  nectar  of  flowers.  Some  beetles,  however, 
are  destructive  as  imagos  only  {Ilylohius  ahietis,  L.,  etc.). 
Ametabolic  insects  also  feed  in  the  pupal  stage.  The  appetite 
of  larvae  in  both  groups  is  enormous,  and  there  are  larvae 
which  eat  daily  more  than  their  own  weight  of  food. 

Insects  may  be  termed  caniicorous  ox  phytophagous,  according 
as  their  diet  is  animal  or  vegetable.  Most  insects  useful  to 
the  forester  belong  to  the  former  category,  whilst  plant-feeders 
are  all  more  or  less  injurious. 

*  The  symbol  ?  denotes  the  female,  ^  the  male,  and  >?  the  worker,  or 
imperfect  female. 


15H  PROTECTION    AGAINST    INSECTS. 

In  accordance  with  their  choice  of  nutriment,  insects  may 
be  classed  as  mono-,  yoly-  or  imntophagons.  Monophagous 
insects  only  attack  certain  plants  or  at  most  a  group  of  plants, 
such  as  broadleaved,  or  coniferous  trees.  Polyphagous  insects 
attack  trees  of  both  kinds,  whilst  pantophagous  attack  herbage 
as  well,  and  are  least  numerous  of  all.* 

Observations  are  not  yet  complete  regarding  the  monophagy, 
or  polyphagy  of  certain  insects.  The  hitherto  accepted 
monophagy  of  some  insects  has  often  been  upset.  Tomkus 
typociraphns,  L.,  and  T.  amitiniis,  Eichh.,  formerly  considered 
exclusive  to  spruce,  have  also  been  found  on  Scots  pine  and 
larch.  Myelopliilus  •pinipcrda,  L.,  has  been  found  on  spruce, 
as  well  as  on  Scots  pine.  In  this  respect,  the  observation  of 
beetles  is  more  difficult  than  of  Lepidoptera,  that  live  in  the 
open. 

Even  amongst  carnivorous  insects,  monophagous  and  poly- 
phagous species  are  to  be  found.  Many  parasitic  insects,  for 
instance,  attack  only  a  single  species  of  moth,  and  in  one  stage 
only  of  its  growth,  in  the  egg,  larval,  or  pupal  state. 

Conifers  suffer  much  more  than  broadleaved  species  from 
insect-attacks.  They  afford  nourishment  to  a  greater  number 
of  injurious  kinds,  and  do  not  recover  from  damage  so  readily, 
as  they  cannot  replace  injured  members  so  easily  as  broad- 
leaved trees.  The  Scots  pine  and  the  spruce  are  attacked  by 
the  greatest  number  of  species  of  insects,  and  pure  woods  of 
these  trees  suffer  most  severely.  Amongst  broadleaved  trees, 
oak,  beech,  poplars  and  willows  suffer  most,  the  birch  and 
alder  less,  and  less  still  hornbeam,  maple,  ash.  Least  of  all 
robinia,  mulberry,  walnut,  plane,  sweet-  and  horse-chestnut. 

Suppressed,  weakly,  and  injured  or  diseased  trees  generally 
suffer  more  from  insects  than  healthy  trees  ;  at  any  rate  this 
holds  good  for  mature  trees  with  thick  bark.  Hence  injurious 
insects  increase  and  become  more  dangerous  when  trees  have 
suffered  from  various  climatic  or  physiological  injuries,  or 
those  caused  by  abrasions,  bad  pruning,  etc. 

Species  of  insects  which  live  on  dying,  dead  or  rotten  wood 

*  Tliis  definition  is  that  of  Hess.  As  a  rule,  entomologists  would  hardly 
call  a  species  that  feeds  indifferently  on  PicPii,  Phiux,  and  LitrUi-  monophagous, 
but  would  reserve  the  term  for  those  insects  whose  diet  is  limited  to  a  single 
species  or  genus. 


NUMBER.  1 59 

are  of  no  importance  to  the  forester ;  such  are  the  stag-beetle 
{Lucanus  cervus,  L.),  and  many  species  of  Anohiidae  and 
Ceramhycidae. 

Many  insects  confine  their  attacks  to  fully-grown  or  old 
trees  ;  others  attack  only  young  plants  (Ili/lohius  ahietis,  L.) ; 
others  attack  trees  of  all  ages  {Myelopldlus  inniperda,  L.). 

The  attack  may  be  on  the  roots  {GrylloUdpa  ruh/aris,  L,, 
Melolontha  vidgaris,  Fabr.,  in  the  larval  state)  ;  on  the  bark 
(most  species  of  Tomicus  and  Hylesimis) ;  on  the  wood 
itself  {Trypodendron  lincatum,  Gyll.,  species  of  Sir  ex  and 
Ceramhyx) ;  on  the  leaves  or  needles  (Chrysomela  and 
most  lepidopterous  larvae) ;  on  buds  (Curcidionidae,  Tortri.r 
huoliana,  Schiff.) ;  on  the  blossom  {Anthonomus pomorum,'L.) ;  on 
fruits  (Balaninus  nncum,Ij.,  Ccuyocapsa  jwmonella,  L.,  Tortrix 
strohillcla,  L.)  ;  on  the  pith  {Myelop)hilus  pinipcrda,  L.). 

Many  insects  by  biting  and  sucking  produce  malformations 
termed  (falis  on  leaves,  shoots,  fruits,  etc.  XCy)dps,  Aphis, 
Cecidomyia,  Chermes  and  Coccidae,  etc.) ;  such  damage  is  easily 
discernible,  but  is  of  subordinate  importance. 

Damage  by  insects  reduces  the  production  of  good  seed  by 
the  trees  attacked.  Dr.  A.  Hosaeus  investigated  the  seed  of 
Scots  pine  from  trees  attacked  by  and  free  from  leaf-larvae, 
obtaining  1  and  45  per  cent,  of  good  seed  respectively. 

Section  IV. — Number. 

The  number  of  individuals  of  a  particular  insect  that  may 
coexist  is  in  many  species  limited,  but  in  others  may  attain 
vast  proportions,  especially  under  favourable  circumstances. 
Thus  in  18B4,*  200  square  miles  of  sal  forest  {Shurca  rohusta) 
in  Assam,  north  of  the  Bramaputra  river,  were  ravaged  by 
the  caterpillars  of  Dasychira  Thicaitcsi,  the  trees  exhibiting 
complete  or  partial  defoliation.  The  appearance  of  certain 
insects  shows  a  periodicity,  corresponding  to  the  eleven  years' 
weather  periods. 

Fortunately,  the  most  prolific  of  insects,  plant-lice,  are  not 
the  most  destructive  to  forests ;  these  creatures,  according  to 
E^aumur,  may  produce  5,000  millions  from  one  female  in  the 

*  •'  Indian  Forester,"  vol.  xx.,  p.  2o(;. 


160  PROTECTION    AGAINST    1NSP]CTS 

course  of  live  generations,  and  in  one  summer  ten  such 
generations  may  occur.  Tiie  average  number  of  eggs  of  the 
commoner  injurious  insects  varies  between  100  and  200 
(Piatze])urg).  Warm,  dry  weather  and  plenty  of  food,  and 
breeding-places,  such  as  diseased  wood,  or  branches  broken 
by  snow,  are  very  favourable  to  prolific  multiplication.  Under 
such  circumstances,  insects  that  are  generally  of  limited 
numbers  may  appear  locally  in  destructive  swarms.  Besides 
the  case  of  bark-beetles,  such  an  abnormal  increase  infrequently 
met  with  in  the  case  of  the  grey-tussock  moth  {Dasi/vJiira 
imdihunda,  L.),  allied  to  that  species  which  ravages  the  Indian 
sal  forests. 

One  favourable  season  is  not  usually  sufficient  to  produce 
an  insect-calamity,  but  two  or  more  successive  favourable 
springs  and  summers. 

Most  insects  are  solitary,  but  many,  such  as  bees,  ants, 
certain  kinds  of  wasps,  and  termites,  are  social  and  have  a 
wonderful  organisation,  framed  on  the  principle  of  subdivision 
of  labour.     The  larvae  of  some  moths  are  also  gregarious. 


Section  V. — Useful  Forest  Insects. 

Carnivorous  insects  attack  other  species  in  various  ways,  and 
have  been  subdivided  by  Eatzeburg  as  follows  : — 

Predatory  insects  follow  and  kill  other  insects  in  every  stage. 
Ground-  and  tiger-beetles  belong  to  this  group. 

Predaceoiis  j)arasitic  insects,  like  the  former  class,  seize  other 
insects,  but  carry  them  to  their  nests,  where  their  own  larvae 
feed  on  them.  Such  are  the  fossorial  wasps  {Sjihefjidae  or 
Crabronidae) ;  they  first  sting  their  prey,  but  without  killing 
them,  and  thus  render  them  inert. 

Finally,  2><^if'asltic  insects  wound  the  larvae,  pupae,  or  even  the 
eggs  of  other  insects  with  their  fine  ovipositors  to  lay  eggs  in 
them.  The  larvae  hatching  from  these  eggs  feed  on  the  juices 
of  their  hosts.  Ichneumon-wasps  and  some  Hies  (Tachinae) 
are  examples  of  this  group. 

A  classification  of  these  insects  according  to  their  utility  is 
scarcely  possible  ;  of  predatory  insects,  the  largest  are  generally 
the  most  useful,  especially  species  of  Carahus  and  Calosoma. 


OAMAOE    DONE    BY    INSECTS.  161 

Ichneumon-wasps  and  jiai-asitic  flies  increase  in  numbers  in 
proportion  to  the  abundance  of  their  hosts,  which  bring  about 
an  insect-calamity ;  they  thus  assist  in  suppressing  it,  whilst 
other  animals,  incapable  of  rapid  multiplication,  can  only  keep 
down  the  numbers  of  injurious  insects  in  ordinary  times. 


Section  VI.— Injurious  Forest  Insects. 
•  1.  Damage  done. 

The  grouping  of  insects  that  are  injurious  to  forests  may 
follow  either  the  degree  of  damage  done,  or  the  kind  of  damage, 
or  nature  of  the  attnek. 

(I.  Degree  of  Damage. 

In  accordance  with  the  amount  of  damage  they  do,  we  may 
distinguish  forest  insects  as  highly  injurious,  decidedly,  or 
slightly  injurious.  The  degree  of  resistance  of  the  species  of 
tree,  the  part  of  the  tree  attacked,  and  the  severity  of  the 
attack,  as  well  as  the  abundance  and  voracity  of  the  insect  in 
question,  decide  the  degree  of  injuriousness  for  any  case.  It 
is,  however,  impossible  to  assign  any  strict  limits  to  the  several 
groups. 

An  insect  is  considered  highly  injurious  when  by  the  nature 
and  duration  of  its  attacks,  masses  *of  plants  or  whole  woods, 
otherwise  healthy,  may  be  killed  over  more  or  less  extensive 
areas. 

To  this  category  belong,  e.g.,  Melolontha  vulgaris,  Fabr., 
Hylohius  ahietis,  Fabr.,  Tomicus  typograplius,  L.,  Gasteropacha 
pint,  L.  The  two  former  insects  frequently  destroy  extensive 
areas  of  young  plants,  and  the  two  latter  large  areas  of  forest 
trees. 

Decidedly  injurious  insects  destroy  certain  organs  only  of  trees, 
such  as  the  leaves,  inflorescence  or  fruits,  shoots,  or  stems,  or 
they  weaken  and  eventuajly  kill  plants  here  and  there  in  the 
woods.    Most  injurious  insects  belong  to  this  group. 

Slightly  injurious  insects  hardly  deserve  notice  from  a  forest 
point  of  view,  as  they  only  cause  trifling  damage ;  they  either 
attack  dead  stems  or  tree-parts  without  impairing  their  com- 
mercial value,  or  the  damage  done  by  them  to  leaves,  shoots, 

F.P.  M 


162  PROTKCTION    AGAIXST    INSECTS. 

etc.,  has  no  subsequent  fatal  effect  on  the  plants.     Such  are 
tortrices  and  leaf-miners,  and  many  gall-insects. 

In  a  time  of  exceptional  multiplication,  a  sUglith/  injurious 
insect  may  become  dccidcdhj  injurious,  or  a  decidedly  injurious 
insect,  highly  injurious.  A  single  species  of  insect  may  also 
be  injurious  in  a  different  degree  to  different  species  of  trees  : 
it  may  prefer  one  to  another,  or  one  tree  may  recover  more 
easily  than  another  from  its  attacks.  IJparis  monacha,  L.,  e.g., 
is  far  more  injurious  to  conifers  than  to  broadleSved  trees, 
and  to  the  spruce  than  to  the  Scots  pine. 

I>.  Kind  of  Damage. 

Insects  may  be  classed  according  to  the  kind  of  damage  they 
do,  as  commerciaUij  or  j>//?/s/o/o///ca//j/ injurious.  The  former 
class  renders  useless,  or  greatly  reduces  the  commercial  value  of 
the  part  of  the  tree  they  attack,  as  when  ^YOod  has  been  bored 
by  Sirex,  Ceramhyx,  Anohium,  or  Lyctus. 

Physiological  injury  on  the  contrary  is  that  which  interferes 
with  the  vitality  of  plants,  checking  the  growth,  or  even  killing 
them  outright,  as  when  the  cambium  of  a  tree  is  eaten  by 
Tomicus  typograplms,  L.,  or  the  needles  by  Gasteropacha  pini, 
Li.,  or  by  TJparis  monacha,  L. 

Insects  coming  under  the  second  category  are  therefore  more 

hurtful  than  those  which  rnerely  destroy  wood,   although  the 

.  burrows  of  the  latter  are  sufficiently  conspicuous.     ^loreover, 

most  wood-borers  live  in  dead  wood.     It  is,  however,  possible 

to  pay  too  little  attention  to  commercially  injurious  insects. 

The  degree  of  physiological  injury  depends  on  the  species 
of  insect,  its  mode  of  attack,  numbers,  and  also  on  the  species, 
degree  of  healthiness  and  age  of  the  tree,  the  season  of  attack, 
and  on  other  local  circumstances.  Mention  has  been  already 
made  of  the  greater  susceptibility  of  conifers ;  the  spruce 
suffering  most  of  all,  then  the  Scots  pine,  silver-fir  and  larcli, 
the  latter  bridging  the  way  towards  broadleaved  trees.  Young 
trees,  especially  one  to  three  years  old  plants,  suffer  more  than 
old  ones;  and  injury  in  the  spring  is  more  harmful  than  that 
done  in  summer  or  autumn.  Cambium  eaters  do  more  damage 
than  w'ood-eaters ;  leaf-eaters  more  than  flower  or  fruit-eaters. 

The  healthier  and  stronger  the  attacked  plant,  the  better  it 


DAMAGE    DONE    BY    [NSECTS. 


163 


resists  insects.  On  poor  sandy  soil,  and  in  unfavourable 
situations,  frost-holes,  etc.,  the  damage  done  is  greater  than 
to  plants  in  good  localities,  as  the  repairing  force  of  Nature  is 
then  greatest. 

c.    Charackr  of  the   AUarl\ 

The  attack  may  be  either  primarij  or  secondary  in  character. 
In  the  former  case, 
healthy  trees  are 
injured  by  insects 
attacking  the  leaves, 
buds,  or  seeds;  by 
many  shoot-borers, 
root-gnawers,  and 
insects  which  attaclc 
young  plants  or  sap- 
lings. The  attack 
of  other  insects  is 
only  secondary,  that 
is,  it  is  made  ex- 
clusively, or  by  pre- 
ference, on  plants 
already  weakened  by 
other  causes  (wild 
animals,  fungi, 
drought,  frost,  etc.). 
This  is  specially 
true  of  bark  and 
wood  insects,  which 
abound  in  old  coni- 
ferous trees.  The 
rich  flow  of  tur- 
pentine from  sound 
trees  would  kill  the 
young  larvae.  Cer- 
tain species,  such  as 
the  bark-beetles  of 
stances,  may  make 
secondary  attacks. 

This  distinction  is  of  practical  importance,  as  nothing  can 

m2 


r     , — — ^ 


Fig.  61. — Galleries  made  by  Tenthrcdo  cingtilatn,  Fabr. 
a  Common  bore-hole.        b  Larval  passages, 

broadleaved  trees,  according  to  circum- 
at   one   time   primary  and   at   another 


16*  TROTFXTION    AdATNST    INSECTS. 

be  done  in  cases  of  primary  attack  except  to  remove  the  parts 
of  the  trees  which  have  ah-eady  been  attacked,  together  with 
the  insects  concerned ;  species  wliich  make  secondary  attacks 
can  alone  be  caught  by  tree-traps. 

Species  of  insects  which  occur  in  forests,  but  confine  their 
ravages  to  grasses  and  herbage,  are  of  no  economic  importance, 
unless  these  products  are  of  exceptional  value. 

Finally  species  in  themselves  harmless,  but  which  may  be 
mistaken  for  highl}' injurious  insects,  are  termed  by  Eatzeburg 
deceptive  insects,  e.g.,  Lithosia  quadra,  L.,  the  larvae  of  which 
appear  on  all  conifers,  as  well  as  on  oak,  beech,  etc.,  in  con- 
siderable numbers.  It  is  quite  harmless,  feeding  only  on 
lichens.  It  greatl}^  resembles  lAparis  monacha,  L.,  for  which 
it  is  often  mistaken.  Tenthredo  ciiKjulata,  Fabr.  ;  the  larvae 
feeding  on  bracken,  which  they  often  completely  devour, 
occupy  galleries  of  bark-beetles  under  the  bark  of  pines  and 
make  galleries  of  their  own  in  pine  bark,  without  injuring  the 
trees  in  any  way  (Fig.  61).  The  forester  must  therefore 
learn  to  distinguish  harmless  species  from  other  injurious 
kinds  which  they  may  resemble. 

2.  Preventive  Hides, 
a.  Sylvicidiur(d . 

Since  the  majority  of  injurious  foreign  insects,  especially 
bark-beetles,  prefer  to  attack  sickly,  stunted  or  weakly  forest- 
plants,  and  may  spread  from  these  to  their  healthy  neiglibours, 
the  safest  method  for  preventing  insect  attacks  is  to  follow  the 
rules  which  experience  has  laid  down  in  sylviculture  and  forest 
utilisation  for  the  formation,  tending  and  harvesting  of  woods. 
In  general,  the  following  rules  should  be  observed : — 

(i)  Choices  of  suitable  species  of  trees  and  proper  systems  of 
regeneration.  The  species  must  be  appropriate  to  the  locality, 
and  the  system  must  correspond  to  the  nature  of  the  species 
grown.  It  is  specially  important  to  select  strong  healthy 
plants  for  plantations,  and  to  plant  most  carefully. 

(ii)  Avoidance  of  extensive  pure  woods,  especially  in 
coniferous  forest.  It  is  better  to  grow  mixed  woods,  and  to 
mix  broadleaved  species  with  conifers. 


PREVENTIVE    RULES.  165 

Even  on  sandy  soils,  where  Scots  pine  naturally  thrives, 
a  mixture  of  Weymouth  pine  should  be  introduced,  and  a 
few  birch,  aspen  and  robinia.  If  the  pines  should  bo  killed 
outright  by  insects,  the  wood  will  not  become  absolutely 
bare. 

(iii)  Careful  and  frequent  examination  of  the  woods  for 
injurious  insects.  This  precaution  is  most  important  in  coni- 
ferous woods  on  poor,  dry  soil,  in  warm  localities  and 
especially  during  the  spring. 

It  is  most  important  to  keep  a  careful  watch  round  places 
where  swarms  of  insects  exist,  and  from  which  damage  gene- 
rally extends  in  all  directions.  The  subordinate  Forest  Staff 
must  be  instructed  to  recognise  and  attend  to  the  signs  of  an 
impending  attack  of  this  kind.  Such  signs  are:  unusual  num- 
bers of  woodpeckers  or  cuckoos  in  a  compartment;  bitten-otf 
leaves  or  needles  lying  on  the  ground  ;  spun  threads  hanging 
from  the  twigs ;  withering  of  foliage  :  excrement,  or  boring 
refuse,  or  bore-holes  in  the  stems  ;  exudation  of  resin ;  dis- 
coloration or  peeling  off  of  bark ;  and  appearance  of  numbers 
of  ichneumon-wasps  or  flies,  etc. 

(iv)  Early  and  frequent  thinnings,  without  interruption  of 
the  leaf  canopy,  are  desirable.  Such  thinnings  should  remove 
all  forest  growth  in  a  suppressed,  sickly,  or  even  suspicious 
condition.  A  forester  who  merely  removes  dead  wood  does 
nothing  to  prevent  insect  attacks,  for  in  it  only  unimportant 
species  breed.  Dying  stems  are  the  favourite  resort  of 
bark-beetles. 

(v)  Every  attention  should  be  paid  to  the  rules  for  main- 
taining and  improving  the  quality  of  the  soil.  This  is  best 
accomplished  by  careful  preservation  of  the  soil-covering,  by 
draining  away  any  superfluity  of  moisture,  and  by  timely 
under-planting  woods  of  light-demanding  trees,  such  as 
oak,  larch  or  Scots  pine,  with  shadebearing  ones,  beech, 
silver-fir,  etc. 

(vi)  Suitable  preventive  measures  must  be  taken  against 
damage  by  wind,  frost,  snow,  ice,  fire  or  insects.  Broken  wood 
must  be  worked  up  and  removed  from  the  forest  as  soon  as 
possible,  or  at  least  barked. 

(vii)  In  the  clear-cutting  system,  avoid  large  felling  areas,  so 


166  PROTECTION    AGAINST    INSECTS. 

that  there  may  not  be  extensive  tracts  of  even-aged  woods. 
Several  cutting-series  should  be  established,  by  the  use  of 
severance  fellings,  if  necessary.  This  gives  a  choice  of  the  felling- 
area  for  any  particular  year,  and  contiguous  compartments 
are  not  cut  in  successive  years.  Fellings  should  be  arranged 
against  the  prevailing  winds,  in  order  to  avoid  extensive 
windfalls  and  the  consequent  danger  from  bark-beetles. 

(viii)  Stools  of  felled  trees  should  be  extracted  or  carefully 
earthed  over,  especially  in  coniferous  forests,  as  many  highly 
injurious  species  of  insects  {Hijlohias  ahietis,  and  several 
species  of  Hi/lastcs)  lay  their  eggs  in  stumps  and  roots. 

(ix)  Summer-felling  in  coniferous  forests,  together  with 
careful  removal  of  the  bark.  Wherever  winter-felling  is  advis- 
able for  other  reasons,  some  of  the  stems  should  be  left  lying 
as  traps  and  barked  in  May,  after  the  bark-beetles  have  laid 
their  eggs  in  them.  Wood  felled  during  winter  is  now  usually 
partially  barked  in  strips,  if  it  cannot  be  removed  before  the 
breeding  season  of  the  bark-beetles.  If,  however,  these  beetles 
do  not  find  wood  with  the  bark  on  lying  in  the  forest  they  will 
lay  their  eggs  in  the  bark  of  standing  trees,  while  the  cost  of 
partial  barking  is  considerable,  and  it  is  easier  to  destroy  the 
larvae  in  fallen  timber  than  in  standing  trees. 

(x)  The  forests  must  be  kept  clean,  the  fellings  rapidly  and 
thoroughly  cleared,  and  material  from  thinnings  carted  away 
without  unnecessary  delay. 

Further  preventive  measures  against  many  species  of  insects 
are :  turning-in  swine  for  "  pannage,"  the  employment  of 
caterpillar-trenches,  wood-traps,  grease  rings,  etc.  As,  how- 
ever, these  measures  are  remedial,  as  well  as  preventive,  they 
will  be  discussed  further  on. 

(xi)  Rewards  should  be  offered  to  the  Protective  Staff  for 
discovering  injurious  insects  and  for  special  zeal  shown  in 
carrying  out  the  rules  for  destroying  them. 


h.  l^iolection  of  I/isfrUrorou.s  A)u)NaJs. 

Only  those  animals  should  be  protected  which  do  more 
good  by  the  destruction  of  insects  than  harm  in  other 
ways. 


IXSECT-EATIXG    BIRDS.  167 

The  following  are  the  principal  insectivorous  vertebrates  : — 

Mammals. 

All  bats,*  especially  Ves})eru(jo  noctula,  Shreb.,  J',  discolor, 
Natt.,  I',  p'qnstrellus,  Schreb.  The  mole,  shrews,  especially 
Sorex  vulf/aris,  L.,  the  hedgehog,  pole-cat,  stoat,  weasel  and 
badger.  These  beasts,  some  of  which  have  been  already 
referred  to  as  mice-destroyers,  should  be  unconditionally 
protected. 

The  fox  also  devours  numerous  insects,  particularly  large 
beetles,  and  the  wild  pig  is  very  useful  in  the  case  of  insect- 
attacks. 

Birds. 

The  following  birds  deserve  unconditional  protection : — 

The  common  cuckoo  {Cuailus  canorus,  L.)  ;  woodpeckers, 
the  wryneck  {J/jnx  torquilla,  L.) ;  the  night-jar  {Caprimahjus 
europaens,  L.) ;  the  swift  {Cijpselus  apiis,  L.) ;  the  tree-creeper 
{Certhia  familiaris,  L.)  ;  the  nut-hatch  {Sitta  caesia,  Wolf)  ; 
all  swallows  {Hinuido,  L.) ;  wagtails  (Motacilla,  L.) ;  pipits 
{Anthiis,  Beehst.) ;  hedge-sparrow  (Accentor,  Bechst.)  ;  gold- 
crest  {Rcfjidiis  cristatus,  Koch) :  wren  {Troglodytes  pariulus, 
•Koch);  redstart  {II.  pkoeidciinis,  L.) ;  stonechat  {Saxicola 
ruhicola,  L.) ;  wheatear  {S.  ocnantlie,  L.) ;  flycatcher  {Muscicapa, 
L.) ;  titmice  {Pants,  L.)  ;  starling  {Sturnus  vulgaris,  L.). 

•The  various  species  of  wagtail  eat  insects  and  also  small 
snails,  Limnaea  sp.,  which  are  the  hosts  of  the  liver-fluke  {Distoma 
hepaticiim)  that  is  so  destructive  to  sheep.  The  goldcrest  hunts 
throughout  the  year  for  the  eggs,  larvae  and  pupae  of  insects 
and  for  scale-insects  on  coniferous  trees.  So  do  titmice,  espe- 
cially the  coal-tit  {Varus  major,  L.),  P.  ater,  L.,  P.  cacrulius,  L., 
P.caudatus,  L.,  and  P.  cristatus,  L.  The  starling  is  esj^ecially 
useful  in  clearing  off  cockchafer  grubs  from  meadows.  They 
have  been  seen,  at  Coopers  Hill,  to  pick  them  out  of  the 
nursery,  from  the  side  of  Scots  pine  plants  which  showed  no 
signs  of  attack.  The  bird  walks  along  the  line  and  hears  the 
larvae  working  below.  It  also  destroys  ^Yire- worms  and  surface 
caterpillars. 

*  Except  the  fruit-bat3,  called  iu  India  flying-foxes. 


168  PROTECTION    AGAINST    INSFXTS. 

Among  liaptorcs,  all  owls  except  the  eagle-owl  {Bnho  k/navus, 
Foster).  Gulls;  the  black-headed  gull  {L(triis  ribihundiis,  L.)- 
This  latter  frequently  follows  the  plough,  and  destroys  cock- 
chafer grubs  and  wire-worms.  The  cuckoo  is  exceptional 
among  the  above  birds  for  its  power  of  eating  hairy  caterpillars, 
which  other  birds  reject.  Altum  found  the  remains  of  97  young 
Cncthocampa  larvae  inside  a  cuckoo. 

Of  owls,  the  long-eared  owl  {Asio  otus,  L.)  and  the  tawny 
owl  {Sijrnium  abico,  Boie)  are  the  most  useful  against  insects. 

The  following  birds  merit  conditional  protection  : — 

Passcres  :  finches  {Fringillidae)  ;  larks  {Alaudidae} ;  thrushes 
{Turdidae) ;  the  jackdaw  {Conns  monedula,  L.) ;  the  common 
and  hooded  crows  (C  corone,  Lath.,  and  C.  comix,  L.)  ;  the 
rook  {C.fru[iile[ius,  L.). 

The  above-mentioned  passerine  birds  do  damage  in  various 
ways,  chiefly  as  grain-eaters,  but  are  also  useful  in  destroying 
insects.  Where  the  damage  predominates,  they  must  be  kept 
down.  Thrushes  and  blackbirds  hunt  in  the  forest  for  iusect 
larvae  and  pupae,  and  distribute  the  seeds  of  useful  shrubs  an^l 
trees. 

Raptorcs :  the  honey-buzzard  (Peniis  <q)i corns,  Gray)  ; 
common  buzzard  {Bnteo  luhjaris.  Leach) ;  the  kestrel  (Fah-o 
tinnuncuhis,  L.)  hunts  crickets  and  cockchafers,  it  does  no 
harm  to  game. 

Limicolae  :  woodcock'  (Scolopacc  rusticola,  L.)  ;  snipe  {(Jal- 
linago) ;  golden  plover  {Charadrhis  phivialis,  L.)  ;  lapwing 
{Vanellus  vulgaris,  Bechst.). 

The  lapwing  destroys  large  numbers  of  wire-worms  and 
beetles,  aphidae,  and  the  larvae  of  numerous  insects  feeding  on 
crops.  Unfortunately  the  search  for  their  eggs  is  very 
persistent. 

The  following  birds  do  indirect  damage,  by  killing  useful 
birds  or  eating  their  eggs  : — 

Passeres :  shrikes  {Lanius,  L.)  ;  jay  {Garridiis  ylandarius, 
L.)  ;  magpie  (  Pica  rustica,  Scop.) ;  raven  {Covins  corax,  L.). 

liaptorcs  :  All  species  except  those  already  mentioned. 

It  should  be  noted  that  shrikes  kill  mice  and  insects  as  well 
as  small  birds. 

The  mere  protection  of  birds  useful  to  forests  is  not  suthcient ; 


INSECT-EATING    BIRDS. 


169 


means  for  promoting  their  multiplication  should  also  be  under- 
taken.    The  following  points  should  be  attended  to  : — 

(i)  Preservation  of  a  few  hollow  trees  in  forests,  as  such  trees 
harbour  useful  birds  and  bats. 

(ii)  The  provision  of  boxes  or  vessels  for  nest-building  on 
trees.  These  may  be  made  of  earthenware,  of  wood,  of  plaited 
straw,  or  tarred  basket-work.  Even  dried  hollow  bottle-gourds 
may  be  used  for  titmice.  The  earthenware  vessels  should  be 
of  the  shape  given  in  the  figure,  and  have  a  wooden  base,  and 
before  hanging  up  should  be  tarred  and  covered  with  moss. 


Figs.  62  and  63. — Earthenware  uesting-pots. 

a,  Nail-hole  for  attachment  to  the  tree,  b,  Hole  for  insertion  of  a  wooden  peg 
to  assist  the  hird  in  entering,  c,  Flight-hole.  d,  Iloles  for  the  passage  of  a  wire, 
to  attach  the  bottom  of  the  pot  to  a  piece  of  wood. 


The  wooden  nesting-boxes  invented  by  Gloger  *  in  1853  are 
made  out  of  half-inch  boards,  and  tarred.  There  are  six 
kindfe,  including  those  shown  in  the  figures,  and  suitable  for 
starlings,  flycatchers,  and  titmice.  Some  are  used  for  the  birds 
to  sleep  in  as  well  as  for  nests.  The  horizontal  partition 
shown  in  the  figures  excludes  cats,  pole-cats,  and  other  enemies, 
and  also  keeps  the  nest  warm.  It  is  essential  to  keep  to  the 
dimensions  indicated  by  the  reduced  figures,  or  the  nesting-box 
will  be  used  by  other  species,  for  which  it  was  not  intended. 

*  "Nist-uml  Sciilafkasteii  fiir  Vogcl."  Ally.  Funst  ii.  Jagd.  Zeituny^  l;Sf)4, 
I).  120.     Prices  are  there  given  for  the  nesting-boxes. 


170 


PROTKCTION    ACAIXST    INSECTS. 


Outside.  luside. 

Fig,<.  G4  and  05.— Nestiug-box  lor  Stailiug-s,  Wagtails.  "Wrynecks 


Fig.  G7. — Inner  view  ot  a  Imix  witli 
several  compartments  for  a  number 
of  Titmice  or  similar  birds. 


Nkstino-hoxks  of  Wood. 
ThcJujuicH  rcduml  to  ^^  of  the  natural  nizi: 


INSECT-EATING    BIRDS. 


171 


The  following  rules  apply  to  the  manner  of  hanging-up  the 
nest-boxes : — 

The  boxes  should  be  hung  facing  towards  the  east  or  south 
only  :  never  towards  the  west. 

As  starlings  are  sociable  birds,  several  boxes  for  them 
may  be  hung  at  a  height  of  20  to  25  feet  on  the  same 
tree,  but  for  other  species  only  one  box  should  be  hung  on 
a  tree. 

Boxes  for  titmice  should  be  hung  10  to  IG  feet  high  in  a 
dark  place,  best  of  all  in  coniferous 
forest,  on  silver-Hr  or  spruce  trees. 

Boxes  for  redstarts  and  flycatchers, 
on  the  contrary,  should  be  hung  10 
to  16  feet  high  under  light  groups  of 
trees,  and  on  the  borders  of  thin 
places  and  clearings. 

(iii)  Shrubs  shouki  be  planted  in 
sheltered  places,  along  a  brook,  or 
by  a  si)ring,  as  water  is  a  necessity 
for  birds,  also  on  rocks,  steep  places, 
etc.  Suitable  bushes  are  privet, 
honej'suckle,  viburnum,  elder,  white 
thorn  and  wild  roses  ;  as  an  over- 
growth, pollard- willows  and  moun- 
tain-ash.   Undergrowth  should  also 

be  carefully  preserved  in  high  forest,  unless  it  must  be  cut 
for  sylvicultural  reasons. 

(iv)  The  birds  should  be  fed  when  deep  snow  is  on  the 
ground.  Bread  or  boiled  pulse  should  not  be  given,  as  these 
substances  become  acid  "and  unwholesome  after  wetting.  For 
insectivorous  birds  pieces  of  suet  or  chopped  meat  are  suitable. 
Thorns  should  be  placed  over  the  food,  so  that  crows,  doves, 
and  sparrow-hawks  may  be  kept  off.  The  following  places  are 
most  suitable  as  feeding  grounds : — high  ground  for  titmice, 
tree-creepers,  woodpeckers  and  finches ;  roads  for  yellow- 
ammers  and  hedge  and  tree-sparrows ;  fields  and  gardens  for 
robins,  linnets,  finches,  and  migratory  birds  from  the  north  ; 
for  fieldfares,  thrushes  and  blackbirds,  the  food  should  be 
placed  under  a  shady  conifer  at  the  edge  of  the  forest ;  the  places 


Fig.  68. — Xestiug-box  for  tlie 
Starling,  of  tarred  straw. 


17^  PROTECTION    AHAINST    INSECTS. 

which  goldcrests  and  wrens  frequent  should  be  ascertained,  and 
the  birds  fed  there. 

(v)  Forest-litter  should  not  be  removed  from  March  till 
Jul3%  as  many  useful  birds  nidify  on  the  ground,  or  close  to 
it,  and  would  be  disturbed. 

(vi)  Birdsnesting  and  the  trapping  or  killing  of  useful  birds 
should  not  be  allowed. 

In  continental  forests,  enormous  numbers  of  thrushes,  field- 
fares and  similar  birds  are  caught  ever}^  year  in  the  autumn 
and  winter  by  means  of  horse-hair  nooses  attached  to  the 
trees.  Wherever  such  bird-catching  is  allowed,  the  open 
season  should  be  limited  to  the  period  between  the  1st  of 
October  and  the  1st  of  Februar}'. 

Legal  enactments  to  protect  useful  birds  are  necessarily 
made  by  the  State,  and  should  be  properly  enforced. 

A  convention,  dated  19th  March,  1902,  has  been  made  for 
the  protection  of  useful  birds  between  all  the  principal 
countries  in  Europe,  except  the  United  Kingdom,  Holland, 
Belgium,  Paissia,  and  Norway.  The  Wild  Birds  Protection 
Act  became  law  for  the  United  Kingdom  in  1880.  It  has 
since  been  slightly  amended  in  1881,  1894,  1896,  and  in  1902. 
As  the  destruction  of  vermin  in  country  districts,  the  curtail- 
ment of  the  area  of  cultivation,  and  the  protection  atYorded  by 
the  Act  to  wild  birds  have  upset  the  balance  of  Nature — bull- 
finches, starlings,  blackbirds,  thrushes,  and  sparrows  do  much 
hj^rm,  especially  in  orchards.  Except,  however,  for  a  scheduled 
list  of  rare  birds,  that  no  one  may  kill  during  a  close  time, 
owners  and  occupiers  of  land  and  persons  authorised  by  them 
may  kill  other  birds  during  the  close  time. 

licjit'dcs  and  Aiitphihia.  • 

Toads,  frogs,  and  lizards  are  ver}'  useful  as  insect  and  slug 
destroyers,  especially  in  gardens  and '  forest  nurseries,  but 
the}^  are  not  nearly  so  numerous  as  useful  birds  and  mammals. 
Snakes  and  slow-worms  are  also  useful,  but  the  poisonous 
adder  {Pclias  hems,  L.)  will  naturally  not  be  protected. 
Adders  are  found  all  over  Europe,  in  brushwood  and  on 
sunny  slopes  among  stones.  They  feed  chiefly  on  mice 
and  moles. 


SPIDERS.  1 73 

Insects. 
A  detailed  account  of  the  chief  useful  insects  follows  in 
Chapter  V.  Their  number,  especially  that  of  ground-beetles, 
ichneumon-wasps  and  Tachinae,  increases  steadily  with  that 
of  the  destructive  insects ;  this  fact  is  all  the  more  important 
as  the  activity  of  mammals  and  birds  altogether  fails  to 
combat  such  calamities  successfully. 

Spiders. 

Spiders  (Arachnoidea)  include  two  distinct  families  of  insect- 
destroyers,  Araneinae  and  Phalangiinae,  both  of  which  are 
great  destroyers  of  insects.  The  common  garden-spider 
{Kpeira  diadema,  CI.)  and  Steatoda  sisijphia,  CI.,  may  be  taken 
as  examples  of  the  former  class,  and  the  common  harvest-man 
(PJialaiif/inm  parietliiuin,  de  Geer)  of  the  other.  The  first 
catches  many  small  beetles  and  other  insects  in  its  large 
vertical  nets  expanded  in  the  underwood  of  forests,  the  second 
species  destroys  large  numbers  of  Lophyrus  pini,  L.,  as  well 
as  other  insects.  The  harvest-men  become  very  active  in  the 
evening,  moving  about  rapidly  with  their  long  stilt-like  legs, 
and  preying  on  small  insects,  plant-lice,  etc. 

The  web-making  spiders  may  do  some  slight  injury  to 
plants  by  their  webs,  which  interfere- with  the  full  development 
of  blossoms  and  foliage. 

Mijnaj)oda. 

Centipedes,  of  which  Litkohius  forjicatus,  L.,  is  an  example, 
and  millipedes,  for  instance,  Iidus  terrestris,  L.,  live  under 
bark,  stones,  and  moss,  and  kill  numbers  of  insects,  also  slugs 
and  siiails.  Species  of  lulus  also  attack  fleshy  roots  in  gardens 
and  fields,  as  well  as  wheat,  and  fruit  such  as  strawberries ; 
they  also  appear  to  cut  off  seedlings  at  the  collar  in  a  manner 
similar  to  wireworms. 


3.  lie  medial  Measures. 

In  considering  the  measures  to  be  taken  in  attacking  insects, 
we  must  select  the  proper  season,  and  adopt  means  which  do 


174 


I'ROTFXTION    AfiAINST   INSECTS. 


not  entail  a  greater  expenditure  of  time,  troulAe,  and-  money 
than  the  results  will  justify. 

In  general,  the  following  rules  may  be  adopted  : — 
(a)  Collection  and  destniction  oj  eggs,  larvae,  jnipae  or  perfect 
insects.  This  is  unfortunately  impracticable  for  most  injurious 
species,  or  is  too  protracted  a  method,  except  in  the  case  of 
perfect  insects.  A  knowledge  of  the  life-history  of  any 
particular  insect  will  inform  the  forester  of  the  stage  in  which 
it  is  best  attacked,  but  for  practical  reasons  a  season  should 


Figs.  G9  and  70.-- Caterpillar  shears  {rcditccd). 

Front.  liaek. 

a.  Cord.     b.  Spring,     c.  ]\Ioveable  blade. 


be  chosen  for  their  destruction,  when  the  requisite  labour- 
force  is  available. 

Collections  of  insect-eggs  can  be  made  only  when  the}'  are 
laid  in  clusters,  as  thoH^  of  mole-crickets,  the  lackey-moth, 
and  the  black-arches  moth.  The  simplest  method  of  destroying 
the  latter  is  to  crush  them  on  the  tree. 

The  larvae  of  Lepidoptera  and  sawHies  may  be  collected  by 
shaking  the  attacked  poles  or  saplings,  or  by  beating  with 
a  mallet  or  the  butt-end  of  an  axe  at  the  base  of  the  branches 
of  trees,  so  that  the  larvae  fall  on  to  a  cloth  spreM  on  the 
ground.  Care  must  be  taken  to  protect  the  hands  of  collectors 
by  gloves  against  hairy  caterpillars,  which,  when  handled, 
cause  inflammation.     "When  in   groups  on  the  trees,  larvae 


REMEDIAL    MEASURES.  175 

may  be  crushed,  and  branches  bearing  the  spun  web-Hke 
nests  of  certain  gregarious  kinds  may  be  cut-off  with  pruning- 
shears  (Figs.  69,  70),  or  they  may  be  burned  on  the  trees  by 
holding  torches  under  them.  Larvae  fall  most  readily  from 
trees  in  the  early  morning  and  evening  or  during  moist,  cool 
weather.  The  larvae  of  but  a  few  species  of  beetles  can 
be  profitably  collected,  for  instance,  cockchafer  grubs.  In 
Massachusetts,  during  the  great  plague  of  the  gypsey  moth, 
1897,  Liparis  dispar,  L.,  matting,  termed  burlap-hands,  was 
'put  round  the  trees  and  the  larvae  pupate  under  these,  or 
rest  under  them  in  the  day-time  and  may  thus  be  destroyed. 

The  collection  of  pupae  is  best  effected  when  they  lie  in 
clusters  in  the  moss  and  dead  leaves  of  the  soil-covering,  such 
as  the  pupae  of  Noctua  piniperda,  Panz.,  or  hang  low  down  the 
stems  in  bark  cracks,  or  on  undergrowth. 

Perfect  insects  may  be  collected  by  simply  picking  them  by 
hand  from  the  ground,  by  shaking  them,  like  larvae,  from  the 
plants  on  which  they  settle,  or  by  means  of  traps  made  of 
strips  of  bark,  laid  on  the  ground  flat  or  rolled-u]),  into  which 
the  insects  crawl ;  this  is  a  common  method  of  catching  great 
numbers  of  the  pine- weevil  {Ifi/Iohiits  abietis,  Fabr.).  The 
bark  should  be  fresh  and  laid  with  the  underside  downwards. 
Other  materials  used  as  traps  are  faggots,  logs,  and  brush- 
wood. Cockchafers  and  pine-weevils  are  the  injurious  insects 
chiefly  captured  in  this  stage. 

In  collecting  the  imagos  of  insects,  it  is  necessary  to  capture 
the  female  alone,  and  that  before  she  has  laid  her  eggs.  This 
can  only  be  done  practically  in  the  case  of  those  Lepidoptera, 
in  which  the  $  can  be  readily  distinguished  by  her-  size  and" 
by  the  nature  of  her  antenna;  from  the  <?  . 

Larvae,  pupae,  and  imagos  may  be  killed  by  pounding  them 
in  trenches,  or  by  pouring  boiling  water  over  them,  or  by 
quicklime,  etc. 

(b)  Preparation  oj  Insect  Trenches.  These  are  useful  on 
any  but  very  sandy  soil  against  larvae  which  wander  on  the 
ground,  r.g.,  those  of  the  pine-moth,  also  against  certain 
beetles,  for  instance,  the  pine-weevil,  Hyhhius  abietis,  L. 
They  should  be  made  10  inches  broad,  and  12  to  14  inches 
deep,  with  vertical  walls,  and  with'holes  8  to  10  inches  deep 


176  PROTECTION    AOAINST   INSECTS. 

every  10  yards  along  their  floor.  They  cost  Ihl.  to  Id.  a 
meter,  or  about  12.s.  per  acre  enclosed.  The  trenches  must  be 
inspected  every  morning,  and  the  insects  which  have  been 
caught  should  be  killed. 

(c)  Greased  harriers.  A  line  of  barked  poles,  covered  with 
grease,  is  made,  so  as  to  exclude  affected  woods  from  sur- 
rounding hitherto  immune  woodlands,  or  to  enclose  small 
areas  of  unaffected  woods.  This  method  is  applicable  only 
for  larvae  that  come  down  to  the  ground. 

(d)  Siciue  marj  he  driven  into  iroods  which  are  attacked,  and 
they  kill  numbers  of  larvae  and  pupae  which  are  in  the  soil- 
covering.  The  swine  must  be  given  other  food  and  driven 
daily  to  water.  As  a  rule,  they  eat  only  hairless  larvae  {Xoetna 
piniperda,  Panz.,  Geovietra  jnniaria,  L.). 

(e)  Pnlling-np  plants  and  burning  shoots  which  have  been 
attacked ;  or  buds  attacked  may  be  pruned  off;  Infested 
branches  should  be  cut  off. 

Stems  full  of  insects,  or  their  eggs,  etc.,  may  be  cut  down 
and  barked,  and  the  bark  burned  or  exposed  to  the  sun.  This 
should  be  done  before  the  perfect  insects  emerge,  usually  in 
May  and  June.  Great  care  must  be  taken  as  to  the  proper 
season  for  barking  such  trees,  which  form  so  many  tree  traps. 
If  it  be  done  too  soon,  before  the  bark-beeiles  have  Ihiished 
breeding,  there  is  danger  of  other  standing  trees  being  attacked, 
and  if  it  be  done  too  late,  after  the  perfect  insects  have  forced 
their  way  out  and  flown  away,  then  the  very  institution  of 
tree-traps  will  liave  multiplied  instead  of  diminishing  the 
numbers  of  the  insects.  It  is  therefore  better  to  bark  the 
traps  before  the  larvae  have  pupated,  and  to  be  informed  when 
this  happens,  infected  trees  should  be  observed,  about  every 
14  days,  in  order  that  the  development  of  the  larvae  may  be 
known  and  the  right  moment  chosen  for  destroying  them. 

(f)  rreparation  of  tree-trajis.  Trees  may  be  specially  girdled 
to  serve  as  traps  before  the  eggs  are  laid.  For  such  purposes 
stunted  or  sickly  trees  should  be  selected 'as  for  thinning 
purposes.  After  the  insects  have  visited  them  they  should  be 
treated  like  trees  attacked  in  the  natural  course. 

(g)  Grease  hands  made  of  various  substances  such  as  tar, 
glue,  and  grease,  may  be  painted  on  trees,  about  chest  high, 


REMEDIAL    MEASURES.  1?7 

in  order  to  stop  larvae  on  their  way  to  the  crowns  of  the  trees, 
and  starve  them  to  death.  They  are  used  chiefly  against  the 
larvae  of  the  pine-moth.  //<///<  hands,  6 — 8  metres  high,  are 
also  made  against  young  larvae  that  have  just  hatched  out  of 
the  nun-moth. 

(h)  Clearance  of  infested  areas.  The  whole  wood  may  he 
cleared  and  the  soil  thoroughly  cultivated  after  burning  all  the 
branches,  etc.,  which  are  infested  with  larvae.  This,  of  course, 
is  a  last  resort.  The  thorough  cultivation  of  the  soil  is 
necessary  only  when  it  is  full  of  hibernating  larvae  or  pupae, 
Lophyrus  nifus,  Eatz.,  etc. 

(i)  Sj)rai/in[i.  Trees  and  plants  in  orchards  or  in  forest 
nurseries  may  be  sprayed  with  certain  substances  to  keep  off 
insects,  such  as  lime-water,  whitewash,  potassium  sulphide- 
solution,  decoction  of  tobacco,  etc.  A  good  recipe  appears 
to  be  1  lb.  of  pure  unslaken  lime,  mixed  with  about  70  gallons 
of  water.  The  lime  is  slaked  and  then  mixed  with  the 
water  and  stirred  up  to  form  a  milky  fluid,  which  is  allowed 
to  stand  till  the  lime  is  deposited ;  the  water  is  then  used  on 
the  trees.  The  lime  can  be  used  again  for  five  or  six  times 
the  quantity  of  water.  The  application  is  useful  as  long  as  the 
insects  are  still  in  the  larval  or  pupal  stage. 

The  sulphur  solution  is  made  by  dissolving  one  part  of 
potassium  sulphide  in  500  parts  of  water,  and  the  foliage  is 
sprayed  with  this  solution.  This  drives  all  the  caterpillars  at 
once  from  the  tree,  and  sprinkled  leaves  escape  further 
damage ;  five  men  in  two  days,  with  38  lbs.  of  potassium  sulphide, 
and  the  necessary  water,  can  sprinkle  250  trees,  at  a  total  cost 
of  50  shillings,  or  five  trees  for  1  shilling. 

The  most  valuable  mixtures  for  tree-spraying  are  arsenical 
washes  or  kerosene-emulsion.  The  former  are  made  by  stir- 
ring about  1  lb.  of  Paris-green  or  London-purple  into  200 
gallons  of  water,  with  the  addition  of  a  little  flour  or  dextrin, 
and  keeping  it  constantly  stirred  during  the  operation  of 
spraying.  As  this  mixture  is  poisonous,  it  cannot  be  used 
where  there  is  risk  of  injury  to  game.  If  it  scorches  the 
foliage  it  must  be  further  diluted. 

Kerosene-emulsion  is  made  by  emulsifying  1  gallon  of 
kerosene  oil  with  half  a  gallon  of  boihng  water  in  which  a 

F.P.  N 


178  I'KOIKLTION    AGAINST    INSECTS. 

pound  of  soft  soap  has  been  dissolved.  It  should  be  con- 
stantly churned  for  ten  or  more  minutes,  and  is  diluted  for 
use  by  gradually  stirring  in  11  or  more  gallons  of  \Yater.  It 
is  especially  -suitable  for  suctorial  insects,  whereas  arsenical 
preparations  chiefly  serve  for  biting  insects. 

(k)  ConduiUnri  Remarks. — A  fuller  account  of  all  these 
methods  \\\\\  be  given  further  on,  under  the  heading  of  each 
species.  Nature  itself  can  relieve  the  forest  best  from  insect 
attacks,  for  ichneumon-wasps,  fungoid  diseases,  and  damp, 
cold  weather  kill  off  myriads  of  insects  and  eventually  put  an 
end  to  any  abnormal  swarms  of  a  -destructive  species  which 
may  occur. 

As  a  rule,  such  a  swarm  lasts  three  years,  but  there  may  be 
a  partial  swarm  one  3'ear  before  and  after  this  period. 

In  Prussia  and  Saxony,  very  large  sums  of  money  have  been 
spent  on  the  destruction  of  forest  insects  ;  in  Prussia  according 
to  the  following  table  : — 

1870-73  ....  ^'41,740 
1876-80  ....  i;98,738 
1884-87       ....     it28,200 

This  shows  a  large  diminution  since  1880,  from  which  it 
may  be  inferred  that  insects  are  diminishing  in  the  Prussian 
forests. 

In  Saxony  during  the.years  1876-77,  £55,852  were  spent  in 
the  destruction  of  pine-weevils  and  bark-beetles. 

4.  Treatiiifiit  of  Injured  ]\'uo(h. 
Woods  injured  by  insects  should  be  felled  only  when  there 
are  signs  that  they  have  been  fatally  injured.  Such  signs  are : 
dryiug-up  or  wilting  of  buds,  shoots  or  twigs  over  the  greater 
part  of  the  crowns  of  the  trees ;  development  of  small  leaves 
or  needles,  the  latter  frequently  in  rosettes;  exudation  of 
watery  turpentine  from  the  bark ;  loosening  and  subsequent 
separation  of  the  bark ;  appearance  of  brown  or  bluish  spots 
on  the  bast  or  sapwood  ;  abundance  of  insects  such  as  species 
of  Cerambyx,  Sircx,  and  Anohium,  which  live  only  on  dead  or 
dying  wood.  In  deciding  on  the  importance  of  such  signs,  we 
must   consider   the    special  circumstances  of  each  case,   the 


REMEDIAL    MEASURES.  179 

insect,  the  species  of  tree  attacked,  its  age,  the  locaHty,  etc. 
Beetles  kill  trees  sooner  than  caterpillars.  Coniferous  wood 
is  more  easily  killed  than  broad-leaved  trees,  and  whole 
spruce  and  pine  woods  are  readily  destroyed  when  badly 
attacked ;  silver-fir  and  larch  make  a  better  resistance.  Broad- 
leaved  trees  are  not  killed  if  every  leaf  on  them  is  eaten,  pro- 
vided the  buds  are  uninjured.  Birch,  elm,  and  ash  die  more 
readily  than  oak  and  beech.  Young  trees  succumb  more 
quickly  to  beetle  attacks  than  older  trees.  On  a  good  soil  a 
recovery  is  more  hopeful  than  on  a  poor  one  ;  clearance  of  the 
wood  should  be  less  readily  undertaken  in  the  former  case. 
The  best  time  for  clearing  is  in  the  winter  after  the  attack. 
The  large  trees  should  first  be  felled,  barked,  and  removed 
as  soon  as  possible  from  the  forest.  Fire-wood  billets  should 
be  got  ready  as  soon  as  possible,  and  at  least  the  larger  pieces 
barked. 

Before  stacking,  the  split  wood  must  be  thoroughly  dried, 
the  stacks  must  be  raised  from  the  ground  on  transverse 
pieces,  and  placed  apart  in  well-ventilated  places.  The 
removal  of  all  split  wood  must  be  expedited. 

Young  plantations  which  have  been  attacked  and  killed  must 
be  replanted.  Injured  poles  require  the  greatest  care  ;  if  they 
are  so  young  that  transplants  can  be  brought  in,  this  should 
be  done,  if  necessary,  after  widening  the  blanks.  Shade- 
bearers,  such  as  the  beech,  hornbeam,  silver-fir,  or  spruce,  are 
very  suitable  for  planting  in  such  cases,  or  else  larch, 
sycamore,  or  Douglas  fir,  on  account  of  their  rapidity  of  growth. 
If,  however,  the  poles  are  too  tall,  and  still  too  dense  to 
be  underplanted,  either  a  clearing  must  be  made  of  the 
whole  crop,  and  the  area  restocked  by  sowing  or  planting, 
or  the  wood  should  be  heavily  thinned  and  undei'planted 
with  a  shade-bearer. 


180 


CHAPTER  Y. 

INSECTS  USEFUL  TO  FORESTS. 

It  is  most  essential  tliat  in  combating  the  attacks  of 
injurious  forest  insects  the  forester  should  be  able  to  distinguish 
insect  friends  from  foes,  and  unimportant  species  from 
hurtful  ones. 

The  following  is  therefore  a  short  account  of  the  most 
useful  families  of  insects,  which  are  found  chiefly  in  the 
orders  of  Coleojjtera  and  Hymenoptcra. 

OrvDER    I. — COLEOPTERA. 

1.  CicindeUdac  [T'ujer  Beetles). 

Perfect  insects  of  moderate  size,  slender ;  mandibles  power- 
ful, with  three  teeth ;  antennae  filiform,  with  eleven  joints. 
Legs  long  and  slender,  with  five  tarsal  joints.  Abdomen 
of  six  segments,  the  three  first  fused.  Larvae  long,  some- 
what flattened  and  humped  in  the  middle,  with  a  broad 
head  and  six  feet. 

The  larvae  dig  vertical  holes  as  thick  as  a  quill  in  the 
sand,  and  remain  at  the  entrance  with  projecting  head,  in 
wait  for  any  passing  insects  or  worms,  which  tliey  seize  and 
suck  dry.  The  beetles  prefer  sandy  and  sunny  localities, 
especially  white  sandy  roads,  are  very  active,  alternately* 
running  and  flying  over  short  distances,  and  greedily  devour 
other  insects. 

One  genus,  Cicindela,  with  a  few  British  species  ;  of  these, 
C.  campestris,  L.,  is  the  only  one  with  an  extended  distri))utiou 
in  suitable  woodland  localities. 

2.  Carahidae  {Gronnd-Beetles). 

Perfect  insects  variable  in  size,  but  often  large  ;  mandibles 
smooth  or  with  only  one  tooth ;  antennae  filiform,  with 
eleven  joints. 


USEFUL    COLKOPTERA.  ISl 

Few  of  the  larger  species  have  functional  wings.  Legs  thin 
and  long,  for  running,  with  five  tarsal  joints.  Abdomen  of 
six  to  eight  segments,  the  three  first  fused. 

Larvae  long  and  cylindrical,  with  six  legs. 

The  beetles  live  through  the  winter  under  moss,  stones 
and  pieces  of  bark,  in  old  rotting  stumps,  etc.,  pair  in  the 
spring,  and  lay  their  eggs  in  the  ground.  The  larvae  live 
either  in  or  on  the  ground,  and  eventually  pupate  in  the  soil. 

Both  the  larvae  and  perfect  insects  destroy  other  insects  in 
all  their  stages ;  the  larvae  in  particular  are  very  voracious, 
and  mostly  prey  at  night.  The  family  is  rich  in  genera  and 
species. 

The  following  large  species  are  most  useful  in  forests  where 
they  occur :  Carahus  catenulatus,  Scop.,  C.  (jranulatus,  L., 
C.  cancellatiLs,  III.,  Calosoma  inquisitor,  L.,  etc' 

Other  species  are  found  on  the  Continent,  such  as  Procrustes 
coriaceus,  L.,  Carahus  auratus,  L.,  C.  auronitcns,  Fabr,, 
C.  sylvestris,  Panz.,  Calosoma  sycophanta,  L. ;  the  latter,  which 
appears  in  great  numbers  when  there  is  a  plague  of  insects, 
and  seeks  its  prey  in  the  crowns  of  trees,  destroying  the  larvae 
of  destructive  Lepidoptera,  is  especially  valuable. 

Certain  species  of  Harpahis  and  I'terosticJius  devour  coni- 
ferous seeds  when  covered  with  moss,  and  Zahrus  gibhus,  Fabr., 
is  destructive  to  young  wheat. 

3.  Staphylinidae  {Ilove  Beetles). 

Perfect  insects  usually  of  small  size,  long-bodied,  and 
characterised  by  very  short  elytra,  which  leave  the  greater 
part  of  the  abdomen  exposed.  Antennne  generally  threadlike, 
with  10  to  11  joints.  Tarsi  mostly  5-jointed,  but  occasionally 
with  three  or  four  joints. 

The  abdomen,  consisting  of  6  to  7  free  segments,  is  turned 
up  at  the  approach  of  any  possible  enemy. 

The  larcae  are  long,  with  six  legs.  The  pupal  stage  occurs 
mostly  in  autumn,  and  the  beetles  live  over  the  winter. 

The  mode  of  life  of  these  very  active  beetles  resembles 
that  of  the  ground-beetles.  Both  larvae  and  images  of  the 
larger  species  feed  on  other  insects,  but  from  a  forest  point 
of  view  they  are  of  less  importance  than  the  ground-beetles. 


1S2  PTtOTECTIOX    AOATXST    INSECTS. 

The  larvae  are  found  especially  under  moss,  but  the  beetles 
chiefly  in  decomposing  substances,  such  as  fungi,  dead  leaves, 
dung,  carrion,  etc.  There  are  nearly  800  British  species. 
The  largest  species  are  :  Ocj/pns  olens,  Miill.  (the  "  Devil's 
coach-horse "),  Staphylinus  caesareus,  Cederh.,  Crcophilus 
ma.villosus,  L.,  etc.  Larvae  of  small  species  of  Stajyln/linidac 
occupy  the  galleries  of  bark  beetles,  and  probably  eat  their 
eggs  and  larvae. 

4.  -SUphidae. 

T^^'r/Z^'s  flattened  oblong  or  oblong-oval,  usually  witli  11-jointed 
clubbed  antennae ;  thorax  with  a  flattened  side-margin ;  anterior 
coxae  conical ;  tarsi  5-jointed.  Usually  dull,  black,  and  often 
rugose  or  ribbed. 

Both  the  larvae,  which  have  6  legs,  and  the  beetles  live  in 
carrion  and  decomposing  substances.  Some  genera,  such  as 
Silpha,  Fabr.,  attack  insects.  Silplia  quadripunctata,  L.,  lives 
in  summer  on  oak  trees,  and  feeds  on  caterpillars,  etc.  It 
has  the  margins  of  the  thorax  and  the  elytra  ochre-yellow, 
the  latter  with  two  black  spots  on  each. 

5.  NitiduUdae. 

Beetles  small,  oval  or  oblong,  with  straight  clubbed, 
11-jointed  antennae  inserted  under  the  frontal  margin. 
Tarsi  short,  usually  with  5  joints.  Abdomen  with  5 — 6 
segments. 

Larvae  long,  with  projecting  horny  head  and  G  legs.     The 
flattened  genera,  JiJiizophaguft,  Bhst. ,  iind  Piti/opJiafiim,  Shuck., 
which  live  under  the  bark  of  trees  of  both  broad-leaved  and* 
coniferous  species,  are  regarded  as  enemies  to  bark-beetles. 

C).  Colydiidae. 

Beetles  small,  thin,  and  long,  with  8 — 11-jointed  clubbed 
antennae.  Tarsi  4-jointed.  Abdomen  of  5,  rarely  of  6,  seg- 
ments, of  which  the  first  three  or  four  are  fused.  Larvae 
long,  and  sometimes  with  horny  plates  below  ;  6-legged. 

The  species  of  this  family  live  in  decaying  wood,  in  fungi, 
or  under  the  bark  of  trees,  and  are  predaceous. 

ColijdliDH  ehmiiatnm,  Fabr.,  locates  itself  in  old  oak  trees,  and 


USEFUL   COLEOPTERA.  183 

destroys  the  larvae  of  bark-beetles,  such  as  Xijlehdrus  dryo- 
firaphiis,  Er.,  etc. 

The  Cohjdiidae  and  the  closely-allied  Cucujidae,  many  of 
which  have  similar  habits,  are  as  a  rule  very  rare  in  Great 
Britain  and  therefore  of  little  local  economic  value. 

7.  Coccinellidao, 
or  Ladyhirds,  are  small,  smooth,  hemispherical  beetles,  with 
red  or  yellow  elytra,  spotted  with  black.    Antennae  very  short, 
clubbed,  10 — 11-jointed.     Tarsi  3-jointed.     Abdomen  of  five 
free  segments. 

The  larvae  are  long  and  pointed  behind,  therefore  somewhat 
lizard-like  in  shape  ;  they  possess  six  legs,  and  are  covered  with 
warty  tubercles,  pits,  or  spines.  Those  of  the  commonest  species 
are  slaty-grey,  with  four  or  six  yellow  spots.  The  beetles  fly 
in  the  spring,  and  lay  their  yellow  eggs  in  clusters  on  plants. 
The  larvae  pupate  in  July  and  August,  hanging  from  the  leaves; 
in  14  days  the  beetles  appear,  and  they  pass  the  winter  under 
dead  leaves,  bark,  etc.  Both  in  the  larval  and  perfect  states, 
and  especially  in  the  former,  they  eagerly  hunt  and  kill  num- 
bers of  plant-lice  or  aphides,  and  mites,  which  do  much  mischief 
to  fruit  and  forest  trees. 

Ladybirds  are  migratory  when  abundant,  and  sometimes 
appear  in  certain  localities  in  enormous  numbers.  The  com- 
monest species  are  :  C.  septcnqmitetata,  L.,  the  7-spotted  lady- 
bird, and  A.  hipunctata,  L.,  the  2-spotted  ladybird.  Certain 
species  are  found  only  in  forests,  as  Ilalyzia  oceUata,  L.,  chiefly 
on  pines,  //.  octodccimgiittata,  L.,  on  spruce.  Scymnns,  Kugel., 
lives  chiefly  in  coniferous  woods. 

8.  Maiacodennnta^ 

This  group  of  families  is  characterised  as  loWov^s:— Beetles 
generally  long,  with  soft  flexible  elytra.  Antennae  slender, 
10 — 12-jointed.  Tarsi  5-jointed.  Abdomen  of  6 — 7  free  seg- 
ments. The  females  sometimes  resemble  larvae.  Larvae  long, 
flat,  and  generally  hairy,  with  six  legs. 

The  predaceous  families  included  in  this  group  are :  the 
Telephoridae,  black,  brown,  or  yellowish  beetles,  about  haU 


]Hi  PROTECTION   AOAINST   INSECTS. 

an  inch  long,  of  which  Tdephorm  fiiseus  is  a  common 
brown  species.  They  usually  feed  on  other  insects,  but  that 
species  and  T.  ohscunis,  L.,  have  been  observed  sucking  5 — 15- 
year-old  shoots  of  oak  and  Scots  pine,  which  then  turn  black 
and  die. 

Their  larvae  are  also  carnivorous,  feeding  on  earth-worms  and 
ground  insects ;  they  pass  the  winter  in  the  earth,  or  under 
stones,  and  during  thaws  sometimes  come  out  on  the  snow. 
They  pupate  in  the  spring. 

The  Cleridae  are  small,  cylindrical,  hairy  beetles,  with  very 
short  serrate  antennae,  somewhat  thickened  at  the  ends.  Tarsi 
with  4 — 5  joints.  Abdomen  of  six  segments.  Larvae  long,  and 
generally  rose-coloured,  w  ith  horny  head,  G-iegged.  The  beetles 
pair  in  the  spring,  and  the  eggs  are  laid  in  the  bark  of  trees, 
under  which  the  larvae  live.  New  beetles  appear  in  the 
autumn. 

The  larvae  and  beetles  hunt  the  grubs  of  bark-beetles  in  their 
borings,  and  also  eat  dead  animal  substances. 

ClerusformicariuSyli.,  is  the  best  known  species,  and  its  larvae 
are  frequently  found  in  the  borings  of  jSIiielophilnsinnipcnla,  L., 
and  the  beetle  may  be  frequently  seen  in  the  forest  running 
about  over  heaps  of  firewood  and  felled  trunks.  It  is  gaily 
coloured,  black,  with  the  greater  part  of  the  thorax  and  the 
base  of  the  elytra  red,  the  latter  also  crossed  by  two  white 
bands.  The  species  is  locally  common  in  conifer-woods  in 
Great  Britain,  and  is  the  most  important  insect-enemy  to 
Scolytidae  we  possess. 

Order  II. — Hymenoptera. 
1.  Iclincumonidae.* 
Certain  allied  families,  such  as  the  Braconidac,  Chalcididae, 
and  Pteromalidae,  are  included  in  this  description.  In  this 
book  these  insects  are  termed  ichneumon-wasps  to  avoid  con- 
fusion with  certain  parasitic  flies  (Tachinae)  of  similar  habits 
belonging  to  the  order  of  Diptera. 

Imagos  of  various  sizes,  long  and  slender.  Head  with  three 
ocelli.     Antennae  generally  slender,  rarely  clubbed,  and  with 

*  For  a  complete  account  of  Gei-nian  iclmeumons,  vide  Taschenberg  (Die 
Ilymeuopteieii   Dcutsclilaiids),  Leipzig,   18GG, 


USEFUL   HYMENOPTERA.  185 

many  joints.  The  veins  of  the  wings,  when  a  submarginal 
vein  exists,  form  distinctly  closed  cells,  but  it  may  be  absent 
and  the  system  reduced  to  one  or  two  veins. 

Trochanters  '2-ringed,  tarsi  generally  5-jointed. 

Abdomen  frequently  stalked,  and  in  the  female  provided  with 
a  long  ovipositor,  formed  of  a  slender  borer  and  two  lateral 
Bheaths. 

Larvae  soft  and  tapering  at  both  ends,  generally  white,  and 
without  hair  or  legs. 

Pupae  with  the  limbs  free,  soft,  and  white. 

The  season  for  the  flight  of  these  extremely  useful  insects 
falls  between  May  and  August.  The  $  lay  their  eggs  either  on 
or  in  other  insects  (Lepidoptera,  beetles,  and  Hymenoptera), 
which  they  pierce  with  their  ovipositors,  generally  attacking 
the  larvae,  less  commonly  the  pupae,  and  seldom  the  perfect 
insects.  Certain  minute  species  attack  the  eggs.  Only  the 
larger  larvae  are  attacked  as  a  rule.  An  ichneumon  will  rarely 
attack  an  insect  which  has  already  been  pierced. 

The  larvae  appear  soon  after  the  eggs  have  been  laid,  and 
may  pass  the  winter  in  the  pupae  of  the  host. 

They  pupate  in  cocoons,  sometimes  outside  the  host,  some- 
times enclosed  in  its  own  pupal  skin  ;  the  species  of  Pteromaltis 
alone  form  exceptions  to  this  rule.  The  ichneumon-wasps  cut 
out  a  round  piece  from  the  cocoon  to  emerge,  passing  the 
winter  under  moss,  in  stumps,  etc. 

The  whole  series  of  transformations  generally  requires 
3 — 6  weeks,  and  the  generation  is  usually  single,  but  sometimes 
double. 

Ichneumon-wasps  are  shy,  and  run  and  fly  rapidly  ;  they  do 
not,  however,  go  far  from  their  birthplace  ;  they  may  appear 
in  great  numbers,  and  are  constantly  quivering  their  wings. 

Most  of  the  larvae  are  parasitic  within  their  hosts,  whose 
juices  they  suck,  but  some  remain  outside  them  (many  species 
of  Pteromalidae  and  Ckalcididae) .  Infested  larvae  continue 
living,  and  eat  ravenously  in  order  to  supply  their  parasitic 
guests  as  well  as  themselves ;  they  do  not,  however,  reach 
maturity,  but  die  either  as  larvae  or  pupae.  As  a  rule, 
ichneumon-wasps  increase  more-  than  proportionally  to  the 
injurious  insects.     Thus,  in    the  valleys  of  the  Ehine  and 


186  PROTECTION    AGAINST   INSECTS. 

Main  (1888-89)  in  the  great  plague  of  pine-moths,  in  the  first 
year,  only  8  per  cent,  of  larvae  were  attacked  by  ichneumons, 
in.  the  second  year,  30  per  cent. 

It  was  formerly  believed  that  most  insects  which  did  not 
attain  full  development  were  killed  by  insect- parasites,  and 
breeding  cages  covered  with  coarse  network  were  maintained 
in  which  all  larvae  infected  by  ichneumon-w^asps  or  flies  were 
placed  and  fed.  The  network  allowed  the  latter  when  fully 
developed  to  escape. 

These  cages,*  however,  have  proved  useful  only  in  allowing 
the  life-history  of  the  parasites  to  he  studied. 

It  is  now  well  known  that  insects  are  destroyed  in  large 
numbers  by  bacteria  and  by  fungi,  the  spores  of  which  find 
entrance  into  their  bodies  either  through  their  skin,  or  amongst 
their  food.  De  Bary  says  :  "If  one  carefully  examines  the 
dead  leaves  and  moss  of  the  forest  soil  in  wet  seasons,  it  is 
astonishing  how-  many  fungus-infected  insects  he  will  find." 
The  infected  caterpillars  may  be  easily  recognised  by  dis- 
coloured s])ots  on  their  bodies,  and  by  their  reduced  activity, 
and  they  die  when  the  mycelium  of  the  fungus  has  spread 
inside  them.  Thus,  miiscardiiw  is  a  well-known  disease  of  the 
silkworm,  due  to  Botrytis  hassiana,  Bals.,  and  this  fungus 
attacks  Noctua  piniperda,  Panz.,  Gastroimiha  pirn,  L.,  and  other 
caterpillars.  AVet  years,  being  favourable  to  the  fructifica- 
tion of  the  fungi,  cause  these  diseases  to  spread  amongst 
caterpillars,  f 

The  question  whether  ichneumons  or  parasitic  plants  are  of 
more  importance  from  a  forest  point  of  view  is  still  open.  It 
was   believed    by   Eatzeburg    that   ichneumons    attack    only 

*  In  Beii^^al,  where  a  Tacliinid  fly  attacks  silkworms,  these  are  sometimes  fed 
inside  a  framework  covered  with  gauze  to  exclude  the  flies.  The  most  usual  plan, 
however,  is  to  rear  the  Bengal  nuilti  vol  tine  silkworm  for  silk  in  alternate  months 
only  (it  has  seven  or  eight  generations  in  the  year) ;  during  the  other  months  a 
limited  numljcr  of  worms  are  carefully  kejjt  under  gauze  to  produce  eggs  for  the  next 
brood.  1"he  fli(!s,  which  have  also  a  generation  every  month,  not  finding  sutlicient  silk- 
worms to  lay  their  eggs  in,  arc  thus  greatly  reduced  in  numbers,  whereas,  if  the  silkworms 
are  bred  in  the  open  every  month,  whole  broods  would  be  destroyed  by  the  parasites. 

t  For  an  account  of  fungi  attacking  insects,  rule  Conki  's  A'ci;!  fable  "Wasps  and 
riant  WormSj  London,  1S1);J,  also  Judeich  and  Nitclir,  Miiti  1(  iiiii]i:ii>.liru  Insecten- 
kunde,  Vol.  I.,  pp.  1G4— 182  ;  De  Bary,  A.,  VerglcicliriHlr  .Mnrphol.ini,.  und  Riologie 
der  Pilzc,  Mycetozoen,  und  Bacterien,  Leipzig:  W.  Engelman,  1884. 


USEFUL    HYMENOPTERA.  187 

insects  already  diseased  owing  to  infection  by  parasitic  plants 
or  the  weather,  and  the  importance  of  ichneumons  is  due  in 
his  opinion  not  to  their  secoudari/  activity  in  attacking  insects, 
but  to  the  fact  that  the  approaching  end  of  an  insect-calamity 
may  be  predicted  from  the  increase  in  their  numbers.  He 
asserts  that  when  50  per  cent,  of  the  caterpillars  are  attacked 
by  ichneumons,  it  is  not  worth  while  spending  any  more 
money  on  measures  for  destroying  the  caterpillars,  as  the 
calamity  will  then  die  out  speedily. 

Taschenberg*  and  Judeich,!  however,  contest  this  opinion, 
and  consider  that  perfectly  healthy  caterpillars  are  attacked  by 
ichneumons;  their  view  is  now  generally  and  properly  held. 
It  is  impossible  to  imagine  that  an  ichneumon,  such  as  Pimpla, 
which  inserts  its  long  ovipositor  through  the  cracks  of  bark  to 
reach  a  concealed  larva,  can  have  any  accurate  perception  of 
the  state  of  health  of  its  host ;  and  the  experiences  of  those 
who  breed  larvae  in  captivity  show  conclusively  that  this  is  a 
matter  of  indifference  to  the  Ichneumonidac . 

The  families  referred  to  are  very  rich  in  species,  5,000, 
of  which  1,000  are  parasitic  on  destructive  forest-insects. 
Ichneumon-wasps  are  either  polyphagous  or  monophagous; 
many  are  monophagous  to  such  a  degree  that  they  attack  only 
a  particular  species  in  a  certain  stage  of  development,  either  as 
larvae  or  pupae,  etc.  The  greatest  number  of  species  (in  all  thirty- 
nine)  attack  the  pine-moth — Gastropaclia  pini,  L.  Many  are 
found  in  the  black-arches,  the  pine  noctua,  the  pine  sawfly,  etc. 
On  ccjgs:  Teleas  laeiiusculus,  Eatz.  {G.  pini),  and  T.  fcirJirans, 

Eatz.,  are  parasitic. 
„  larvae:  Microgastrr  glohafus,  Nees.   ((7.  pini);   Banchns 

coDipressus,  Fabr.  (Noctua  piniperda,  Panz.). 
,,  pupae :  Anomaloii  xantliojms,  Gvav.  (G.  j)t»/);  /•.'.  loplnj- 

rorum,  Htz.  {Lophiirus  pini,  L.). 
,,  larvae  and  pupae  :  Anomalon  circumjlexum,  L.  {G.  pini); 

Pinipla  instir/ator,  Panz.  {Lipavis  monaelta,  L.  dispar, 

PortJiesia  eJtrj/sorrJioea,  etc.). I 
,,  imafios :  sp.  of  Braeonidae  {SfvopJiosoniu.^  cori/li,  L.,  etc.). 

*  Forstwirthschaftliche  Insectenkuiide,  p.  271. 

I  Wiildverdcrber,  7th  edition,  p.  14. 

X  The  names  within  brackets  are  those  of  the  hosts  in  which  the  parasites  live. 


188  PROTECTION    A(;AINST    INSECTS. 

2.  Sjiltcfi'idae  {Fossoricd  Wanps) . 

Iinagos  with  a  large  head  and  three  ocelli.  Antennae  slender 
and  moderately  long.  ^Fore  wings  flat  and  without  folds,  with 
1 — 4  cubital  cells.  Legs  with  smooth  femora  and  simple 
trochanters.  Tibiae  and  tarsi  fossorial,  and  furnished  with 
strong  hairs  and  spines. 

Al)domen  stalked,  generally  with  seven  free  segments,  and 
always  terminating  in  the  $   with  a  sting. 

The  larvae  and  2'>ii2^(i<-  somewhat  resemble  the  perfect  insects, 
but  have  no  legs. 

These  insects  appear  in  summer,  living  in  pairs  and  building 
their  nests  in  sandy  earth,  in  rotten  wood,  cracks  in  walls, 
etc.  They  attack  plant-lice,  larvae,  i)eetles,  grasshoppers,  and 
spiders,  wound  them  with  their  stings,  and  convey  the  disabled 
insects  to  their  nests  in  order  to  lay  their  eggs  on  them. 
Some  species  close  up  the  cells  in  their  nests,  and  the  larvae 
on  emerging  from  the  eggs  feed  upon  the  captives.  Other 
Spheri'ulae  feed  their  young  with  fresh  material.  "Whilst  these 
insects  are  hunting  their  prey,  they  carefully  close  their  nests 
with  particles  of  sand  or  splinters  of  wood. 

The  following  are  common : — Ammophila  sahidoaa,  L.,  and 
Poinjnliis  riaticiis,  Latr. ;  both  species  live  in  sunny  places  in 
sandy  localities. 

8.  Vespidae  {Wasps). 

Imagos  moderately  slender,  almost  free  from  hairs,  black  or 
brown  with  yellowish  zones,  with  ocelli. 

Antennae  approximate  at  the  base,  elbowed,  and  with  1*2 — 13 
joints,  thickened  at  the  apex. 

Fore  wings  folded  longitudinally  when  at  rest,  with  a  radial 
cell  reaching  to  the  end  of  the  wing,  and  2 — 3  cubical  cells. 

Legs  simple,  without  prominent  hairs  or  spurs. 

Abdomen  stalked,  furnished  with  a  sting  in  the  ?  . 

The  larvae  are  white  or  yellowish,  with  brown  heads,  soft 
and  legless. 

The  species  which  form  this  family  live  either  socially,  or 
are  solitary. 

Those  which  are  most  useful,  from  a  forest  point  of  view, 
are  social  wasps,  consisting  of  three  classes: — J    (drones),   ?  , 


USEFUL  HYMENOl'TERA. 


189 


and  I?  ,  workers  which  are  unfertile  females.  The  eggs  are 
not  laid  by  the  female  immediately  after  fertilisation ;  she 
hibernates  and  commences  the  construction  of.  a  nest  for  a 
new  colony  about  April.  From  the  spring  until  late  in  the 
summer  she  lays  her  eggs  in  the  regularly  hexagonal,  pris- 
matic, horizontal  cells  of  the  nest.     She  is  gradually  joined 


Fhr. 


m 


ri.— Honiet-iujury  to  asli. 
(\(((i(ial  size.) 


Fig.  72. — Horuet-iujiiry  to  alder. 
{Xatural  size.) 


in  her  labours  by  lier  progeny,  of  which  first  ip  ,  then  ?  ,  and 
lastly  the  stingless  3  are  produced.  The  latter  die  soon  after 
pairing.  If  by  any  accident  the  mother  wasp  should  die 
before  any  perfect  females  are  produced,  the  whole  colony 
would  become  extinct.  The  duties  of  the  '?  are  to  continue 
building  the  nest,  to  feed  the  helpless  larvae,  and  to  defend  the 
colony  against  enemies.     The  nests  are  covered  with  a  paper- 


190  PROTECTION    AOAINST    INSECTS. 

like  material,  and  are  constructed  on  trees,  in  a  hollow  trunk 
or  suspended  from  a  branch,  or  in  buildings  or  a  hole  in  the 
ground.  Just  before  pupating,  the  larvae  spin  covers  to  their 
cells.  The  '?  become  torpid  in  the  autumn,  and  their  last 
office  is  to  massacre  the  undeveloped  brood,  which  would 
otherwise  die  of  hunger,  as  their  food-providers  themselves 
are  speedily  killed  by  the -increasing  cold.  The  fertile  females 
alone  leave  the  nest  and  survive  the  winter  in  a  dormant 
condition,  reviving  in  the  spring  to  provide  fresh  broods  for 
the  future. 

Wasps  seize  insects,  especially  moths  and  tiies,  partly  for 
their  own  nourishment  and  partly  to  use  their  juices  as  food 
•  for  their  offspring,  or  even  to  feed  them  with 
the  living  insects.     Tliey  do  a  certain  amount 
of    damage    by    eating    sweet    fruits,     plums, 
grapes,  etc.,   and  especially  the  hornet  {Vcsjya 
crahro,  L.),  by  girdling  2  to  4-year-old  shoots  of 
beech,   birch,   hornbeam,   etc.,  and  by  barking 
ash,  white  alder,  etc. ;  they  prepare  the  bark  by 
chewing  and  mixing  with  a  sticky  secretion,  and 
„.  use  it  for  the  fabrication  of  their  nests.     Jiark- 

Wasp-bottle.  ^^^o  ^^  trees  also  causes  a  flow  of  sap  which  serves 
as  food. 
Where  much  damage  is  done,  hornets'  and  wasps'  nests 
may  be  smoked  out,  or  tar,  kerosene,  or  a  solution  of  cyanide 
of  potassium  poured  into  the  entrance  holes.  Glasses  con- 
taining beer,  etc.,  for  catching  them,  as  shown  in  Fig.  73,  may 
be  hung  up  on  fruit  trees. 

4.  Fonnicidae  (Ants). 
Ants  also  have  three  classes — males,  females,  and  workers. 
The  head  is  triangular  and  very  large  in  the  h  .  There  are 
three  ocelli,  at  least  in  the  J  and  ?  .  The  antennae  have  10 — 14 
joints.  The  wings  are  long  and  with  few  veins.  The 
abdomen  is  stalked  and  often  spherical,  with  a  sting  at  its 
extremity,  or  a  gland  which  exudes  formic  acid.  The  J  are 
generally  much  smaller  than  the  $  ;  both  these  sexes  have  a 
well-developed  globular  thorax,  wider  than  the  head,  and  a 
large  abdomen,     in  the  ^:<   the  thorax  is  very  narrow,  much 


USEFUL    HYMENOITERA.  191 

narrower  than  the  head,  which  is  nearly  as  large  as  the 
abdomen ;    they  are  wingless. 

The  lan-ac  are  thickest,  somewhat  curved,  white,  and  apodal. 
Thejmpae  are  soft  and  white,  with  the  limbs  separately  invested, 
usually  enveloped  in  thick  white  cocoons,  M'hen  they  are  known 
as  ants'  t'iigs. 

The  ants  fly  in  July  and  August  in  still  warm  weather, 
often  in  cloud-like  swarms.  The  ?  ,  which  loses  her  wings  after 
pairing,  either  lays  her  eggs  the  following  spring  in  the  old 
nest,  or  she  forms  a  new  colony  in  the  ground  or  in  a  hollow 
tree.  The  larvae  live  in  thousands  in  the  ant-hills,  and  are 
fed  and  carried  about  by  the  numerous  i? ,  of  which  there  may 
be  5,000  and  more  in  one  ant-heap.  In  case  the  ant-hill 
should  be  disturbed,  the  ':  endeavour  to  carry  the  pupae  to  a 
place  of  safety. 

The  perfect  insects  come  out  at  the  end  of  May,  or  the 
beginning  of  June,  after  the  i?  have  opened  the  cocoons.  First 
appear  the  ?  ,  then  the  S  ,  and  last  the  ^  .  The  J  die  soon 
after  copulation ;  as  the  cold  increases  many  of  the  2  also 
die ;  the  '?  live  over  the  winter.  Ants  are  endowed  with  a 
remarkable  sense  of  locality;  if  their  nest  be  injured,  they 
eject  formic  acid,  which  slightly  burns  the  skin. 

For  a  long  time  past  the  usefulness  of  these  little  animals 
has  been  recognised.  They  attack  and  kill  numerous  insects 
and  larvae,  especially  small  caterpillars,  and  clean  the  forest 
of  many  dead  insects.  In  utilising  other  insects  they  show 
extraordinary  ability  for  creatures  so  low  in  the  animal 
khigdom.  Some  ants,  living  in  hollow  trees,  carry  the  larvae 
of  a  beetle,  Cetonia  aurata,  L.,  into  their  nests,  as.  these  larvae 
chew  up  the  wood  into  small  pieces  for  them ;  in  the  same 
way  Claviger  foceolatas,  Preyssl.,  lives  in  the  nests  of  the 
yellow  ants. 

Plant-lice  are  also  kept  in  ants'  nests,  as  the  ants  use 
the  honey-dew  which  exudes  from  them  to  feed  their  young, 
milking  them  like  cows. 

Trees  at  the  foot  of  which  there  are  ant-heaps  remain 
uninjured  during  wide-spread  devastation  by  caterpillars,  like 
oases  in  the  desert,  and  the  fruit-cultivators  in  the  province 
of  Mantua  place  in  the  spring  of  every  year  a  colony  of  ants 


1  02  PROTECTIOX    AGAINST    INSECTS. 

at  the  foot  of  their  fruit  trees  to  secure  them  against  insect 
attacks. 

It  is  therefore  necessary  to  protect  ants  in  every  possible 
way,  though  unfortunately  their  increase  is  greatly  prejudiced 
by  the  search  for  the  so-called  ants'  ecjgs  for  the  purpose  of 
feeding  young  pheasants,  etc.  This  also  deprives  useful  forest 
birds  of  a  portion  of  their  nutriment.  Henschel*  states  that 
in  the  Austrian  Alps  the  sale  of  dried  ants'  eggs  of  Formica 
riifa,  L.,  amounts  annually  to  50 — 70  hectolitres,  -which  means 
from  96  to  13J:'5'  milHon  ants,  for  1  hectolitre  contains  about 
1,920,000  pupae. 

In  Eussia  also  the  business  is  carried  on  vigorously,  the 
right  of  collecting  pupae  being  leased  on  certain  areas,  one 
man  having  collected  £]?8  worth  in  1^  months. 

The  damage  which  ants  occasion  by  constructing  their 
galleries  and  nests  in  sickly  trees,  or  by  eating  sweet  fruits,  or 
by  burrowing  into  planting-mounds  is  trifling  in  comparison  to 
the  good  they  effect. 

As  representatives  of  the  family  the  following  may  be 
mentioned : — 

Formica  rufa,  L.,  the  common  wood-ant,  makes  great 
heaps  of  needles  in  coniferous  forests,  chiefly  in  those  of 
Scots  pine. 

Lasius  fidiyinosns,  Latr.,  in  old  trees  and  stumps  of  oaks, 
poplars,  willows,  etc. 

Myrmica  rubra,  L.,  very  common  in  forests  under  stones, 
sods,  bark,  etc. 

There  are  species  of  ants  which  by  hollowing  out  nests  in 
standing  trees,  or  by  gnawing  plants,  or  disturbing  mound- 
planting,  are  injurious.  These  are  Camjxinotus  herculancus, 
L. ;  C.  lignipcrdns,  L.  Both  species  hollow  out  large  stand- 
ing and  felled  stems  of  conifers,  chiefly  of  spruce  and  silver- 
fir,  to  a  height  of  30  feet  from  the  base  of  the  trees,  in  a 
manner  that  is  concentric  with  the  annual  rings,  so  as  to 
render  the  timber  unserviceable.  Woodpeckers  frequently 
increase  the  extent  of  the  damage,  which  has  also  been 
observed  on  oaks,  limes,  and  robinias.  Lasius  Jiarus,  Latr. 
injures  young  plantations  of    spruce,  silver-fir,  beech,  ash, 

*  Ceulralbl.  liir  das  gcs.  Forstw.,  1876,  p.  IGO. 


USEFUL   HYMENOPTERA.  193 

larch,  and  sycamore,  by  gnawing  the  plants  on  or  above  the 
roots,  underground.  This  damage  continues  from  spring  to 
July.  As  much  as  60  per  cent,  of  plants  have  been  thus 
killed,  the  weakest  being  selected.  The  best  protective 
measure  is  to  use  ball-planting,  or  to  sow  in  autumn,  with 
as  little  disturbance  of  the  soil  as  possible.  This  damage 
was  especially  marked  in  Silesia,  3,000 — 1,000  feet  above  sea- 
level,  on  dry,  southern  aspects. 


5.  Aphlac  {Been). 

The  imagos  are  thickset  and  generally  hairy,  with  ocelli, 
and  with  a  special  suctorial  labium.  Antennae  approximate  at 
their  base,  elbowed,  the  basal  portion  2-jointed.  Fore-wings 
not  folded,  with  one  radial  and  two  to  three  cubital  cells. 
Legs  hairy,  the  first  joint  of  the  hinder  tarsi  very  large, 
compressed  and  forming  a  triangular  or  quadrangular  plate. 

Abdomen  stalked,  with  a  poisonous  sting  in  the  ?  and  '? , 
which  breaks  off  after  use.  The  larvae  and  pupae  resemble 
those  of  wasps. 

Bees  are  either  solitary,  as  the  mason  and  carpenter  bees, 
or  are  social,  as  in  ihe  case  of  humble  or  honey  bees.  The 
former  have  no  '?  ,  which  are  the  most  numerous  inhabitants 
of  a  hive  of  honey  bees. 

Social  bees  breed  underground  in  mole  runs,  etc.,  in 
hollow  trees,  in  the  pith  of  sound  trees  and  shrubs,  as  ash, 
walnut,  rose  and  raspberry,  or  in  artificial  hives. 

The  imagos  live  on  honey  taken  from  plants  and  on  pollen, 
and  effect  the  fertilisation  of  many  fiowers  by  brushing  oft"  the 
pollen  with  their  large  hind  legs,  and  carrying  it  to  another 
flower.  This  habit  is  a  good  example  of  the  direct  utihty  of 
insects  to  plants. 

Species. — Carpenter  bees  {Xylocojxi  violacea,  Fabr.)  live  in 
old  dry  wood,  especially  in  the  case  of  leguminous  trees.  This 
species  is  not  British,  but  many  others  are  common  in  warm 
countries,  and  slightly  injurious  to  timber.  They  are  large 
and  conspicuous  blue-black  insects. 

The  mason  bee  {CJialicodoma  muraria,  Fabr.)  constructs  its 
cells  of  grains  of  sand  on  walls,  rocks,  etc. 

F.P.  O 


194-  PROTECTION    AGAINST   INSECTS. 

Humble-bees  {BoDihus  tern-stris,  L.)  live  in  the  ground  in 
societies  of  fift}'  to  sixty  members. 

The  hone}^  bee  {Apis  mclUjka,  L.)  is  widely  spread  over  the 
earth.  A  hive  may  contain  1  ?  ,  600  to  800  3  ,  and  15,000  to 
30,000  ^? .  The  2  (queen)  lives  for  five  years,  the  3  only  for 
a  few  weeks,  and  the  '?  for  about  six  months. 


Order  III. — Dipteua. 
1.  AsUhiar. 

Imagos  long  and  generally  slender,  the  face  tufted  with  hairs. 
Eyes  very  prominent,  3  ocelli,  the  suctorial  organs  forming  a 
pointed  piercing  tube.  Antennae  short,  3-jointed,  the  third 
joint  elongate,  not  annulate,  terminated  by  a  short  bristle. 

Wings  when  at  rest  lying  flat  on  the  body.  Legs  stout,  with 
sharp  curved  claws.     Abdomen  with  8  segments. 

Larvae  long  and  cylindrical,  with  very  clearly  marked 
segments,  white. 

The  eggs  are  laid  in  the  ground,  by  choice  in  sandy  soil.  The 
generation  is  annual.  The  perfect  insects  are  bold  marauders, 
they  attack  other  insects  of  all  orders  and  suck  their  juices. 

Species. — Aeilus  cmhronij'ormis,  L.,  common  in  Germany 
and  England. 

2.  Siirphidae. 

tmagos  with  oval  bodies,  very  large  eyes,  and  3  ocelli.  An- 
tennae 3-jointed,  the  last  joint  generally  flattened,  sometimes 
very  long,  with  a  bristle-like  appendage.  Wings  much  inter- 
sected with  veins.  Abdomen  variable  in  form,  with  5  to  6 
evident  segments. 

Larva  leech-shaped,  of  varied  colours. 

Piqja  coarctate,  pear-shaped. 

They  fly  in  July  and  August  in  bright  sunshine.  Their 
flight  is  of  a  hovering  nature  ;  they  remain  poised  over  a 
blossom,  darting  away  when  disturbed,  and  resume  their  hover- 
ing at  the  end  of  their  course,  and  they  emit  a  buzzing  noise. 

The  small  white  oval  eggs  are  laid  on  leaves  and  twigs.  The 
generation  is  double,  or  nuiltiple.  The  larvae,  which  inhabit 
plants,  destroy  plant-lice  by  sucking  out  their  juices. 


USEFUL    DIPTERA.  195 

Common  species. — Syrphus  pirastri,  L.,  frequently  found  on 
fruit  trees  and  on  Scots  pine.     S.  balteatus,  De  Geer. 

3.  MusciiJae  {Flies). 

ImcKjos  generally  short  and  stout.  Eyes,  as  a  rule,  densely 
covered  with  hairs;  ocelli  present.  Proboscis  tlesh3\  Antennae 
short,  3-jointed,  the  terminal  joint  the  largest,  not  ringed,  fur- 
nished with  a  bristle  on  its  dorsal  surface.  Wings  of  moderate 
size,  with  few  longitudinal  veins.  Legs  strong  and  moderately 
long.  Abdomens,  with  4 — 7  apparent  segments,  generally 
scantily  hairy,  sometimes  with  an  ovipositor  in  the  $  . 

Larva  without  legs  or  distinct  head,  soft,  and  generally 
whitish. 

Pupa  coarctate,  round  or  elliptic,  brown  or  blackish. 

Flies  lay  their  eggs  sometimes  in  decomposing  substances, 
sometimes  on  living  animals. 

In  forest  economy,  only  the  parasitic  flies  are  of  importance, 
of  which  the  chief  are  the  Taehininae. 

Many  species  of  these  flies  are  parasitic  in  or  on  the  larvae 
and  pupae  of  other  insects,  as  moths  and  sawtlies.  Their  im- 
portance is  somewhat  less  than  that  of  the  ichneumon-wasps, 
but  they,  nevertheless,  destroy  great  numbers  of  insects.  They 
pupate  generally  outside  the  host,  on  or  under  the  ground. 
The  larvae  not  only  suck  the  juices  of  their  hosts,  but,  unlike 
those  of  the  ichneumon-wasps,  devour  their  viscera. 

Species. — Echinomyiafeva,  L.,  frequent  on  larvae  of  Liparis 
monacha  and  Panolis  pinipevda. 

The  sub-family  Anthomyinae  contains  a  few  species  which  are 
injurious  to  forest  trees,  iox  Q\-A.m\)\Q,  Anthomyia  rujiccps,^le\.g. 
According  to  Theodor  Hartig  the  larva  of  this  species  which 
lives  in  the  ground,  especially  in  burned  sods,  eats  the  seeds 
and  roots  of  coniferous  seedlings. 

Order  IV. — Neuroptera. 

1.  Panorpidae  {Scorpion-jiies) . 

Imufjos  of  moderate  size,  head  prolonged  into  a  beak  bearing 
the  mouth  at  its  extremity.  Antennae  many-jointed,  setiform. 
Both  pairs  of  wings  of  equal  size,  with  few  intersecting  veins, 


196  PROTECTION    AGAINST    INSECTS-. 

and  oiil}'  partiall}'  covei-iiigtlie  abdomen,  sometimes  imperfectly 
developed. 

Larva  ^Yitll  horny  head  and  22  legs. 

The  eggs  are  laid  in  moist  soil,  and  the  larvae  pupate  in  oval, 
hollo  wed-out  lumps  of  earth. 

The  larvae  and  imagos  devour  insects. 

The  common  Paiiorpa  communis,  L.,  flies  about  around  low 
bushes  and  hedge-rows,  and  destroys  the  pupae  of  Li  pans 
salicis,  L.,  etc. 

2.  Sialidae. 

Imagos  of  moderate  size,  with  broad  head,  long  neck  and 
fairly  broad  abdomen ;  with  3  ocelli,  sometimes  absent. 
Mouth-parts  free,  fully  developed.  Antennae  short,  usually 
setiform,  and  many-jointed.  Wings  many-celled,  colourless, 
with  bristles  on  the  veins,  sloping  like  a  roof  when  at  rest. 

Larva  \Yitli  G  short  and  stout  legs,  i^j/^a  elongate,  with  the 
limbs  free. 

Example. — llhaphidia,  L.  The  perfect  insects  fly  in  May 
and  June,  and  lay  their  eggs  in  or  under  the  bark  of  Scots 
pine  or  spruce.  The  snake-like  brown  larvae  live  through  the 
winter,  and  pupate  in  the  spring,  without  any  cocoon  ;  about 
2  to  3  weeks  later  the  imagos  emerge,  li.  notata,  Schum.,  is 
very  useful ;  its  larvae  greedily  destroy  the  eggs  and  larvae  of 
other  insects  which  they  find  on  and  under  the  bark  ;  common 
in  coniferous  woods. 


3.  llcmerohiidae  {Lacc-uiinicil jlics). 

Imagos  long  and  delicate.  Head  small,  with  large  hemi- 
spherical eyes  ;  no  ocelli.  Mouth-parts  free.  Antennae  long, 
setiform,  many-jointed. 

Wings  similar  in  size,  transparent  and  multicellular,  sloping 
like  a  roof  when  at  rest.     Legs  slender. 

Larva  elongate,  and  narrowed  towards  the  ends,  with  tw^o 
slender  curved  mandibles  perforated  for  sucking,  and  G  legs. 

The  flight-period  is  in  the  early  summer,  and  again  in 
autumn.  The  stalked  w4iite  or  greenish  eggs  are  laid  in 
groups  on  leaves. 


USEFt'L   HEMIPTERA.  197 

The  larvae  feed  greedily  on  plant-lice,  which  they  suck  dry ; 
they  can  generally  be  found  wherever  the  latter  are  numerous. 

They  grow  rapidly,  and  pupate  in  lirm,  almost  spherical 
cocoons,  suspended  by  a  few  threads  between  leaves,  from 
which  the  imagos  emerge  in  *2  to  3  weeks.     Generation  double. 

The  commonest  species  is  Chrysopa  perla,  L. 


Order  V. — Orthoptera  (Pseudoneuroptera). 
lAhcUnUdae  {DnKjon-flies) . 

Imafios  long,  usually  very  slender  and  brightly  coloured. 
Head  large,  almost  entirely  covered  with  the  large  many- 
celled  eyes  ;  3  ocelli.  Mouth-parts  strongly  developed.  An- 
tennae short,  fine,  bristle-like,  and  generally  7-jointed.  Wings 
of  equal  size,  many-celled,  and  membranous.  Legs  short, 
strong ;  the  tarsi  3-jointed.  Abdomen  formed  of  11  segments, 
with  a  short  pair  of  forceps  on  the  last. 

The  6-legged  larvae,  and  njjmi)hs  are  characterised  by  an 
extraordinarily  large  labium,  which  can  be  extended  forwards 
from  beneath  the  head  and  serves  for  seizing  prey. 

The  perfect  insects  fly  in  an  extremely  active  manner  in  June 
and  July,  laying  their  eggs  either  on  the  surface  of  the  water 
or  on  water-plants.  The  generation  is  annual,  and  dragon- 
flies  appear  sometimes  in  incredible  numbers. 

The  larvae  and  pupae  live  in  the  water,  and  prefer  small, 
quiet  ponds  full  of  reeds. 

In  all  three  stages,  especially  as  imagos,  they  kill  other 
insects — even  moths. 

Species. — Blue  and  green  dragon-fly — AescJma  jiincea,  L., 
A.  r/mndis,  L.,  common  especially  in  mountainous  countries. 
Libellula  quadrimaculata,  L.,  migrates,  and  therefore  appears 
sometimes  in  large  swarms. 

L.  depressa,  L.,  very  common. 

Order  YI. — Hemiptera. 
The  tribe  Georores  {land-biiris)  alone  includes  insects  useful 
to  the  forester,  and  they  may  be  characterised  as  follows  : — 
Head  small  and  tlat,*  generally  witli  2  ocelli.    Antennae  large, 


I9K  PROTECTION    AOAINST   INSECTS. 

always  lonj];ei'  than  the  head,  4  to  H-jointed.  Body  flat.  Fore- 
wings  liorny  at  the  base  and  membranous  at  the  extremities. 
All  the  legs  generally  similar.  Tarsi  2  to  3-jointed.  Abdomen 
consisting  of  7  to  8  segments. 

Noticeable  for  their  disagreeable  odour. 

The  species  which  live  in  forests  are  useful  l)y  destroying 
larvae  and  plant-lice,  but  a  few  species  are  injurious,  sucking 
young  shoots,  or  the  bast  of  older  trees.  The  imagos  come 
out  late  in  the  summer,  and  pass  the  winter  among  dead  leaves 
or  under  bark.  Pairing  takes  place  in  the  following  spring  and 
the  eggs  are  laid  on  leaves,  shoots,  and  in  cracks  in  the  bark. 

1.   Pentatomidac. 

Imarjos  somewhat  long,  with  2  ocelli.  Antennae  long,  filiform 
or  club-shaped,  and  generally  5-jointed.  Scutellum  large,  and 
reaching  at  least  to  the  middle  of  the  abdomen.  Tarsi 
generally  3-jointed,  with  two  little  lappets  (pidviUi)  between 
the  claws. 

Species — Pentatoma  riifipcs,  L.,  common  in  pine-forests. 

Pyrrhocoris  apterns,  L.,  often  collects  by  hundreds  at  the 
base  of  large  lime  and  other  trees. 

2.  Beduviidae. 

Imar/os  large,  and  longer  than  those  of  the  preceding  family, 
with  projecting  head  and  long  beak.  Ocelli  generally  present. 
Antennae  long,  filiform,  thin,  4-jointed.  Scutellum  small. 
Forelegs  somewhat  thickened,  and  adapted  for  seizing  prey. 
Tarsi  short,  3-jointed,  pulvilli  absent. 

All  the  species  are  predatory  and  able  to  inflict  a  poisonous 
wound  with  the  beak.  The  most  important  as  regards 
forests  is : — 

Genis  vcKjahundus,  L.,  which  lives  in  the  leaf-galls,  pro- 
duced by  certain  aphides  on  elms. 


199 


CHAPTER    VI. 

INJURIOUS    FOREST     INSECTS     (SPECIAL    ACCOUNT 
OF   COLEOPTERA).* 

The  greatest  number  and  the  most  harmful  species  of 
injurious  forest  insects  belong  to  the  orders  Coknptera  and 
Lrpidoptcra.  Next  in  importance  to  these  come  the  members 
of  the  orders  Ilymenoptera  and  Orthoptera.  The  orders  Dip- 
tera  and  Hemiptera,  except  for  the  few  useful  families  already 
mentioned,  include  only  species  which  are  moderately  or 
slightly  injurious,  and  the  Ncui-optcra  in  Central  Europe 
include  no  injurious  species,  although  in  the  south  of  Europe 
and  in  India  and  other  hot  countries,  the  family  of  Termites, 
or  white  ants,  belonging  to  this  order,  is  probal)ly  more 
destructive  to  vegetable  substances,  though  chiefly  when  these 
are  no  longer  living,  than  any  other  insect-family. 

In  the  following  pages  the  more  destructive  families  of 
insects  will  be  enumerated  and  described.  The  life-history 
of  the  most  important  species,  and  their  relations  to  forest 
trees,  and  the  best  known  ways  of  meeting  their  attacks,  will 
also  be  dealt  with,  but  many  less  important  species  which 
occur  in  Dr.  Hess's  book  have  been  omitted.  Hess  has  also 
separated  the  injurious  forest  insects  damaging  conifers,  from 
those  which  damage  broad-leaved  trees.  Owing  to  the  smaller 
number  of  insects  here  dealt  with,  this  distinction  has  been 
ai)andoned. 

Family  I. — Scarabaeidae. 

Description  of  Family. 

Imiufos  generally  of  considerable  size  and  robust  build. 
Antennae  short,  elbowed,  10-  or  11-jointed,  the  first  joint 
elongate,  the  last  3  or  more   joints  produced  inwards   into 

*  For  a  complete  systematic  description  of  British  beetles,  vide  Fowler,  "  The 
Coleoptera  of  the  British  Isles,"  5  vols.,  London,  1886—1891. 


200  PROTECTION'    AGAINST    INSECTS. 

plate-like  lamellae  which  can  l)e  separated  like  the  leaves  of  a 
book. 

The  forelegs  are  formed  for  digging,  and  the  tarsi  are 
5- join  ted. 

The  abdomen  consists  of  5  or  6  segments.  A  generation 
lasts  for  several  years  in  the  ease  of  the  larger  species,  but 
only  one  year  in  the  smaller  ones. 

The  larvae  are  thick,  cylindrical  grubs,  curved  ventrally, 
with  the  last  abdominal  segment  large  and  baggy ;  often 
covered  thinly  with  short  hairs,  which  may  be  bristly  on  the 
dorsal  surface ;  head  well  developed,  horny,  with  distinct 
antennae  ;  legs  6,  strong.     They  generally  live  underground. 

Pupae  almost  hairless,  generally  with  2  horny  processes  on 
the  last  abdominal  segment. 

In  the  perfect  state  these  insects,  some  of  which  are  very 
destructive,  attack  the  leaves,  needles  and  inflorescence  of 
forest  trees,  whilst  their  larvae  eat  the  roots  of  young  woody 
plants.  The  larvae  of  other  species  live  in  rotten  wood,  dung, 
and  in  dead  bodies. 


1.  Mcloloutha  vuhjaris,  Fabr.  {Common  Cockchafer  or 
Maij-huf/). 

a.  Descriplion. 
The  beetle  is  25  to  29  mm.  long  ;  prothorax  black,  less  often 
reddish-brown ;  elytra  and  legs  red-brown,  the  former  with  5 
elevated  longitudinal  ridges,  the  depressions  between  them 
covered  with  fine  down.  Abdomen  black,  with  5  white 
triangular  marks  on  each  side,  produced  at  the  apex  into  an 
elongate  tapering  tail.  Antennae  10-jointed  ;  the  clul)  7-jointed 
in  the  3  ,  in  the  2  smaller  and  only  G-jointed.  Tarsal  claws 
with  a  broad  tooth  at  the  base. 

//.  Life-hislonj. 

The  beetles  appear  at  the  end  of  April  and  in  May  for  about 

3  or  4  weeks.     About  24  hours  after  fertilisation,  the  female 

burrows  into  the  ground,  selecting  a  bare  spot  and,  where 

possible,  a  light  sandy  soil.     In  it,  at  a  depth  of  5  to  10  cm. 


COMMON    COCKCHAFER. 


201 


(2  to  4  inches),  she  lays  about  70  dirty  white  subspherical 
cfifjs  in  little  heaps  containing  from  12  to  30  each.  She  then 
returns  to  the  surface  to  die. 

The  curved  larvae  appear  from  4  to  G  weeks  afterwards,  in 
June  or  July,  feed  in  the  first  year  on  humus  in  the  neighbour- 
hood of  their  l)irth-place,  and  eventually  disperse  in  the 
second  summer  in  all  directions  in  the  ground,  in  order  to 
feed  on  the  roots  of  plants.  In  the  autumn  they  burrow  deeper 
into  the  ground,  returning  near  to  the  surface  in  April. 


Fig.  74. — Melolotithn  vulgcnix,  Fabr. 

a  Imago  (^).      h  Anteima  of  male  with  7  lamellae,      c  Antenna  of  female  with 

6  lamellae,     d  Grub,     e  Pupa  (ventral  surface). 


The  larvae  also  go  deeper  down  when  about  to  imitate  -,  this 
change  takes  place  in  July  or  September  of  the  4th  (rarely  the 
3rd)  year  of  larval  life  in  an  oval  hole  in  the  ground,  the  walls 
of  which  are  internally  smooth  and  water-tight.  In  certain 
isolated  cases,  pupation  is  deferred  until  the  following  spring. 

The  iiiiafjos  generally  imerge  from  the  pupa  from  four  to 
eight  weeks  later,  but  pass  the  winter  in  the  ground,  a  few 
occasionally  appearing  on  the  surface.  From  the  month  of 
February  in  the  5th  or  4th  calendar  year,  the  cockchafers 
come  up  from  below  and  take  flight,  leaving  holes  in  the 
ground  as  if  made  by  a  stick.     The  favourite  flight- time  is  on 


202 


PROTECTION    AOATNST    INSECTS. 


a  fine  evening  in  jMay,  especiallj'  after  a  shower  of  warm  rain. 

In  mountainous  countries,  the  cockchafer  appears  somewhat 

hiter  than  in  the  milder  plains. 

The  (jcncration  differs  in  duration  according  to  latitude  and 

climate,  as  a  rule  lasting  4  years  in  Great  Britain  and  Europe 
north  of  the  river  Main.  This  forms  an 
approximate  boundary,  south  of  which 
the  generation  is  triennial.  In  East 
Prussia,  swarms  of  cockchafers  have 
been  ol)served  at  intervals  of  5  years. 
It  follows  therefore  that  the  time  of 
development  of  the  cockchafer  is  not  the 
same  everywhere,  but  depends,  within 
certain  limits,  on  the  latitude  and  longi- 
tude of  a  place,  and  on  its  corresponding 
climate.  If  there  is  an  unusually  large 
swarm  in  any  given  year  the  same  thing 
will  occur  at  stated  intervals  every  few 
years  according  to  the  locality.  These 
critical  years  are  known  as  swarm-3'ears; 
in  the  intermediate  years  at  least  a  few 
cockchafers  appear,  either  descended  from 
stragglers,  w-hich  have  since  continued  to 
produce  regular  generations,  or  from 
irregular  individuals  in  an  existing 
generation.  In  Switzerland,  there  are 
three  districts,  in  each  of  which  there 
is  a  swarm  of  cockchafers  every  three 
years,  but  in  different  years  for  each 
district.  They  are  termed  the  Bernese, 
Urne  and  Basel  swarm  -  years,  and 
there  is  every  year  a  swarm-year  in  one 
This  fact  has  been  observed  for  more  than 


Fif^.  7o. — Tlirce-year-okl 
beech  gnawed  by  chafer- 
grubs,  with  loss  of  roots. 
{Xa/Hrnl  si:r.) 


of  these  districts. 
160  years. 

In  Chorin,  it  has  been  observed  for  30  years,  that  when  in 
one  part  of  the  forest  there  is  a  swarm-year,  there  are  no 
chafers  in  an  adjoining  part,  and  vice  versa.  This  is  found  to 
be  due  to  the  fact,  that  the  larvae  in  a  swarm-year  eat  all  the 
larvae  of  the  next  year  in  their  burrows.     The  strong  larvae 


COMMON    COCKCHAFER. 


203 


\ 


of  a  swarm-year  also  eat  all  wire-worms  and  other  larvae  they 
meet  with,  besides  the  plants. 

These  swarm-years  have  been  little  noticed  in  Great  Britain 
and  appear  to  be  less  marked  than  on 
the  Continent,  the  number  of  chafers 
appearing  each  year  being  more  uniform. 
There  was  a  swarm-year  at  Egham,  in 
the  Bagshot  sand  district,  in  1898. 

The  flight  of  the  cockchafer  is  some- 
what heavy,  it  flaps  its  wings  up  and 
down  many  times  before  ascending  from 
the  ground,  in  order  to  drive  air  into  its 
trachae.  It  can  endure  unfavourable 
weather  toleral)ly  well,  and  the  larvae  can 
withstand  a  month's  inundation  3  feet  deep. 


c.   Relations  io  ilie  Forest. 

The  cockchafer  is  injurious,  both  in  the 
laval  and  perfect  condition.  The  attacks 
of  the  larvae  are  less  visible,  but  are  more 
harmful,  especially  in  coniferous  woods, 
as  they  affect  the  roots  and  last  for  two 
or  three  summers.  They  are  worst  in  the 
two  last  summers.  Scots  pine  and  spruce 
up  to  10  years  old  are  most  endangered, 
then  the  larch,  and  the  silver-fir  does  not 
escape.  Broadleaved  trees  do  not  suffer 
from  the  larvae  quite  so  much  as  conifers, 
but  nearly  every  species  is  attacked,  those 
with  tender  roots,  such  as  beech  and  ash, 
being  preferred  to  species  like  the  oak, 
which  speedily  develops  strong  roots.  The 
bitten  surface  is  rough  and  fibrous,  and  not 
smooth  as  when  bitten  by  a  pine- weevil, 
or  gnawed  by  a  mouse,  the  work  of  which 
latter  can  be  readily  distinguished  by  the  characteristic  paired 
tooth-marks. 

The  larva  is  extremely  destructive  in  forest-  and  orchard- 
nurseries  and  in  broadcast   sowings ;    whole  rows  of  young 


Fig.    76. — Scots     pine 
roots     attacked     l)y 
chafer  grubs. 
a  Three  years  old. 
b  Two  years  old. 


204.  PROTECTION    AOATNST    INSECTS. 

seedlings  or  pricked-out  plants  may  be  seen  with  drooping 
and  dying  heads,  and  reddish  foliage  or  needles.  If  they  are 
pulled  up,  it  will  be  found  that  the  ends  of  the  roots  have  been 
eaten,  and  occasionally  the  larva  itself  may  be  found  in  situ  at 
the  base  of  the  injured  root.  Figs.  75  and  76  show  the  roots 
of  attacked  beech  and  Scots  pine  seedlings.  The  larvae  are 
also  extremely  destructive  to  meadows  and  agricultural  crops. 

The  imago  attacks  the  foliage  of  broadleaved  species  from 
May  till  July,  probably  sparing  the  robinia  and  pear  only. 
The  oak  is  most  subject  to  this  attack ;  then  follow  maples, 
sweet-  and  horse-chestnut,  poplars,  plum  and  cherry-trees. 
The  beech,  hornbeam,  willow's,  apple,  birch,  plane-tree,  and 
many  shrubs,  etc.,  are  also  attacked,  the  order  in  which  tlie 
different  species  are  selected  depending  on  the  degree  of 
development  they  have  attained  when  the  flight-time  takes 
place.  Conifers  are  less  to  their  taste  than  broadleaved 
species,  but  the  imagos  in  May  and  June  will  feed  on  young 
shoots  and  needles  of  larch,  and  the  male  catkins  of  Scots 
pine  and  spruce,  occasionally  on  the  spring  shoots  of  isolated 
silver-firs.  Trees  standing  in  the  open,  and  border  trees  are 
preferred,  as  the  flight  of  the  insect  to  them  is  less  impeded 
than  it  is  to  trees  in  the  midst  of  a  wood.  Lofty  trees  are  also 
preferred  to  low  growth.  In  1878,  in  the  Austrian  coast 
districts,  Quercus  lyuhescens  suffered  greatly,  and  even  the 
walnut  was  attacked,  a  rare  event.  The  oak  trees  were 
completely  stripped  of  leaves,  but  became  green  again  by 
means  of  Lammas-shoots. 

The  larvae  prefer  sandy  soil  in  sunny  places,  bare,  or  with  a 
scanty  covering  of  grass,  and  large  forest  cultivations  after 
a  clear  cutting.  Extensive  cultivations  of  Scots  pine 
bordering  on  agricultural  land  sufter  most  of  all.  Stiff  soil 
covered  with  dense  herbage,  damp  depressions  and  well-trodden 
paths  are  avoided.  The  pine  forests  of  Brandenburg  show 
how  closely  connected  swarms  of  coclichafei-s  are  with  the 
clear-cutting  system. 

(1.  Proleciive  Ihdes. 
i.  Natural  regeneration  under  a  shelter-wood  system  should 
be  practised.     Supposing  that   this  is  impracticable  owing  to 


COMMON    COCKCHAFER.  205 

local  conditions  of  climate  and  species  of  tree,  narrow  clear-cut 
fellings,  with  reservation  of  standards,  should  be  made.  In 
any  case,  large  clear-cut  felling-areas  should  be  avoided. 
Successive  fellings  should  then  be  continued  only  after  the 
young  crop  on  the  last  adjacent  felling-area  has  been  secured. 
In  districts  where  cockchafer  damage  is  frequent,  fellings 
should  be  reduced  as  much  as  possible  the  year  before  and 
during  a  swarm-year.  Measures  that  keep  the  ground 
sheltered,  cool  and  moist,  render  the  soil  less  suitable  for 
oviposition  and  for  the  larval  life. 

ii.  In  case  sowing  is  advisable,  broadcast  sowing  should  be 
adopted  in  Scots  pine  woods,  together  with  autumn  sowings 
of  corn,  or  of  birch  seed. 

When  only  partial  sowing  is  carried  out,  the  seedlings  come 
up  closer  together  than  in  the  case  of  broadcast  sowing,  and 
there  is  more  danger  of  the  whole  crop  being  destroyed ;  the 
cockchafers  avoid  cereal  crops  and  prefer  not  to  lay  their  eggs 
in  places  covered  with  growing  corn. 

iii.  Planting,  and  especially  ball-planting  with  strong  plants 
is  to  be  preferred  to  sowing ;  otherwise,  notching  with  as 
little  disturbance  of  the  soil  as  possible. 

In  the  Eberswald,  planting  in  pits  the  surface  of  which  after 
planting  is  nearly  a  hand's  breadth  below  the  ground-level, 
was  tried  with  success ;  the  larvae  which  feed  very  near  the 
ground-level  in  summer  crawl  from  the  surrounding  earth  on 
to  the  top  of  the  pits,  instead  of  getting  to  the  roots  of  the 
plants. 

iv.  Pasturing  herds  of  swine  in  all  forest-glades.  In  the 
swarm-years  this  should  be  done  in  spring ;  whilst  the  larvae 
are  in  the  ground,  during  the  whole  summer. 

v.  Protection  of  all  enemies  of  the  cockchafers.  The 
badger,  mole,  shrew,  hedgehog,  rooks  and  crows,  starlings,  etc., 
attack  the  larvae ;  bats,  owls,  goatsuckers,  shrikes,  kestrels, 
and  harriers  destroy  the  cockchafers. 

A  starling  will  often  carry  off  5  or  G  larvae  at  once  ;  these 
useful  birds  eat  only  the  soft  abdomens  of  the  chafers.  Boxes 
for  starlings  to  nest  in  should  be  always  set  up  around  forest 
nurseries. 

vi.  When  laying-out  nurseries,  the  neighbourhood  of  oak 


206  PROTECTION    AGAINST    INSEC'I'S. 

woods  should  be  avoided,  and  the  area  should  be  isolated 
by  ditches.  Beds  are  sometimes  made  with  walls  and  bottoms 
of  stones,  and  filled  in  with  sifted  soil. 

vii.  Oviposition  may  be  prevented  by  covering  the  beds  with 
dead  leaves  or  twigs,  or  by  sprinkling  them  with  Hour  of 
sulphur. 


e.  Ri'iitedidl  Measures. 

i.  The  areas  to  be  stocked,  in  swarm-years,  should  be 
completely  broken  up  with  the  plough,  or  trenched  with  spade 
or  hoe,  in  order  to  destroy  the  larvae.  This  can  be  done  only 
on  fairly  level  ground.  Gas-lime  may  be  ploughed  into  the 
land,  which  must  then  lie  fallow  for  six  months. 

ii.  Collection  in  sacks  of  the  larvae  which  are  turned  up  in 
cultivating  the  ground,  from  June  throughout  the  summer. 
This  is  best  undertaken  before  a  swarm-year,  as  the  larvae  are 
then  nearest  to  the  surface  of  the  ground.  It  may  be  done 
both  in  nurseries  and  before  restocking  felled  areas. 

iii.  Collection  of  the  larvae  by  digging  round  plants  which 
are  attacked  in  the  cultivations ;  this  can  be  done  throughout 
the  summer. 

iv.  The  construction  of  traps  for  larvae,  as  follows : — 

a.  Sods  of  grass  or  heather  in  square  pieces  measuring 
8  to  10  in.  in  breadth  are  placed  with  the  grass  downwards 
on  the  cultivations.  In  the  forest  of  Allstadt,  Weimar,  in  the 
autumn  of  1870,  on  7i  acres  of  ground  covered  with  grass  and 
heather,  square  grass  sods  8  to  10  inches  broad  and  G  to  8 
inches  thick,  were  laid  on  the  surface  of  the  ground  with  the 
grass  downwards,  and  from  3  to  11  larvae  were  found  under 
each  sod  in  July,  1871.  Thus,  in  a  short  time,  l(i,000  larvae 
were  collected. 

h.  ItoUs  of  bark  filled  with  loose  soil,  and  placed  in 
the  ground.  Successfully  done  in  150  Prussian  ranges  in 
1883-84. 

c.  Heaps  of  turf,  weeds,  humus,  burned  sods,  and  dung. 

Such  heaps  afford  looseness,  dryness,  warmth,  and  nourish- 
ment for  the  larval  development,  and  Heyer  greatly  recommends 
their  use  in  nurseries.     The  females  also  readily  lay  eggs  in 


COMMON    COCKCHAFER.  207 

heaps  of  dung  alternating  with  hiyers  of  earth,  and  enormous 
numbers  of  hirvae  may  be  reared  in  them  and  subsequently 
destroyed. 

d.  Traps  of  sticks  or  bark.  In  a  swarm-year  and  the  year 
after  it,  at  the  beginning  of  the  warm  weather,  fresh  pieces  of 
bark  or  thin- barked,  sappy  branches  20  to  40  inches  long  are 
placed  horizontally,  half  covered  with  soil,  in  ground  infested 
with  larvae.  This  may  be  done  between  the  rows  of  plants  in 
nurseries,  and  aspen,  sallow,  ash,  oak,  and  coniferous  wood 
can  be  used.  These  traps  attract  the  larvae.  This  plan  was 
tried  on  a  large  scale  in  150  forest  ranges  in  Prussia  in  1883 
and  1884,  but  gave  only  poor  results.  In  all  the  cases 
(a  to  (/),  the  larvae  must  from  time  to  time  be  collected  and 
destroyed,  and  the  traps  occasionally  renewed.  Oviposition 
may  be  prevented  by  netting  seed-beds,  etc.,  in  the  spring. 

('.  Trap-trenches  one  foot  wide  and  one  foot  deep  are 
filled  with  moss.  These  are  prepared  in  May  and  cleared 
of  larvae  once  a  month  up  to  late  autumn,  the  moss  being 
replaced. 

/.  "When  a  bed  of  seedlings  or  transplants  has  been  seri- 
ously injured,  the  remaining  plants  and  all  weeds  should  be 
removed  and  fairly  deep  trenches  dug  round  the  bed.  The 
larvae  in  the  beds  will  then  be  starved  to  death,  or  come 
out  into  the  trenches,  when  they  should  be  killed.  This  is 
practicable  only  with  larvae  not  ready  for  pupation. 

V.  Collection  of  the  cockchafers  in  April  and  May  is 
probably  the  best  remedial  method  to  be  followed. 

The  chief  points  to  be  noted  are : — The  work  should  be 
commenced  early  in  the  season  before  too  many  cockchafers 
have  emerged ;  then  only  is  it  practicable  to  catch  the  $  before 
they  have  laid  their  eggs.  In  order  to  ensure  economy, 
children  and  women  should  be  employed,  and  the  collection 
made  only  in  the  morning  or  on  cool  days,  when  the  insects 
are  sluggish  in  their  movements.  The  workers  are  provided 
with  narrow-necked  glazed  vessels,  or  sacks  in  the  opening  of 
which  the  broken  neck  of  a  beer  bottle  has  been  fastened,  to 
serve  as  a  funnel  through  which  the  beetles  may  be  dropped ;  the 
trees  should  be  shaken  over  cloths,  and  payment  should  be  by 
quantity.     Birch  border  trees  round  pine  plantations,  planted 


208  PROTECTION    ACiAINST    INSIXTS. 

as  a  protective  belt,  and  border  trees  generally,  should  be  first 
shaken,  as  the  chafers  collect  there. 

The  larvae  and  beetles  may  be  killed  by  : — 

Crushing  on  hard  ground. 

Scalding  with  hot  water,  which  gives  rise  to  an  extremely 
unpleasant  odour. 

Immersion  in  casks  containing  a  mixture  of  water  and 
petroleum,  or  2  per  cent,  of  naphthalin.  Both  larvae  and 
beetles  live  for  some  time  in  water  alone. 

Burial  in  layers  in  a  trench  with  unslaked  lime,  or  powdered 
calcium  chloride. 

Subjecting  the  insects  to  fumes  of  bisulphide  of  carbon. 
This  is  the  best  method  of  destroying  them,  and  was  first 
discovered  by  Dr.  A.  Mayer.  When  done  on  a  large  scale, 
a  clean  empty  petroleum  cylinder  or  similar  vessel  may  be 
used,  in  which  the  carbon  bisulphide  is  poured  on  the 
insects. 

In  order  that  the  gas  may  have  its  full  effect,  the  tin  should 
be  covered  with  a  sack,  or  woollen  cloth,  to  keep  out  the  air. 
Lights  and  fire  must  be  kept  at  a  distance  during  the  opera- 
tion. A  bushel  of  cockchafers  may  be  killed  by  less  than  an 
ounce  of  carbon  bisulphide,  and  the  insects  die  in  from  5 
to  10  minutes. 

Where  cockchafers  are  extremely  abundant  and  injurious, 
as  in  Germany  and  France,  the  expense  of  collecting  them 
is  so  serious,  that  it  is  lightened  as  much  as  possible  by 
the  utilisation  of  the  captured  beetles. 

This  is  done  in  three  ways :  They  are  used  as  food  for  swine, 
fowls  or  geese,  being  mixed  with  three  or  four  times  their 
weight  of  potatoes  or  starchy  material ;  for  the  extraction  of 
a  coarse  oil  suitable  for  cart  grease ;  or  for  manure,  being 
mixed  with  earth,  bone  dust,  or  stable-manure. 

Their  value  as  a  food-stuff  is  about  Is.  per  10  lbs.  ;  as  a 
manure,  about  dd.  per  10  lbs. 

vi.  A  plague  of  cockchafers,  like  a  plague  of  mice,  being 
felt  by  agriculturists  and  fruit-producers,  as  well  as  foresters, 
must  be  met  by  energetic  common  action  of  all  municipalities 
and  village  authorities,  and  in  case  the  interested  parties 
cannot  agree  as  to  any  common  course  of  action,  the  State 


MELOLOXTHA    HIPPOCASTANI.  209 

should  intervene  to  compel  unanimity.  This  is  done  in 
France  by  order  of  the  prefects.  The  damage  done  by  cock- 
chafers to  agriculture  in  France  annually,  in  great  swarm- 
years,  is  estimated  by  Le  Moult  at  £10,000,000,  the  number 
of  larvae  per  acre  being  up  to  150,000  in  bad  cases. 

vii.  Cockchafer  larvae,  termed  vers  hiancs,  have  been  dealt 
with  in  France  by  infecting  certain  of  them  with  Botrijtis 
tenndla  or  Isatis  densa,  and  then  putting  them  into  the 
attacked  field.  The  results  were  not  satisfactory.  Another 
plan,  adopted  in  1896,  for  forest  nurseries  is  to  prepare  cap- 
sules full  of  bisulphide  of  carbon.  These  capsules  are  dibbled 
in,  7  or  8  inches  deep,  and  the  gelatine  gradually  dissolves, 
setting  free  its  contents.  One  thousand  capsules  with  2| 
grammes  of  the  bisulphide  cost25.s.,  and  about  six  are  required 
every  square  metre. 

viii.  Nothing  can  be  done  to  save  conifers  injured  by  the 
larvae,  if,  beside  the  tap-root,  all  side-roots  have  been  bitten 
off.  Should,  however,  some  side-roots  remain,  larch  at  least 
may  recover  if  severely  pruned  almost  to  the  ground  and 
earthed-up  round  the  roots.  The  pruning  limits  the  transpira- 
tion, and  the  earth  round  the  roots  prevents  the  drying-up  of 
the  existing  roots  and  furthers  the  formation  of  new  ones. 
These  measures  must  be  undertaken  as  soon  as  the  injured 
plants  begin  to  droop. 

2.  Melolontlia  liippocastani ,  Fabr. 

The  beetle  greatly  resembles  the  common  cockchafer,  but  is 
smaller,  being  only  20  to  25  mm.  long.  Prothorax  generally 
red,  rarely  black.  Antennae  and  legs  dark  brown  or  black. 
Tail  shorter,  more  abruptly  tapering,  and  somewhat  clubbed 
at  its  extremity. 

lAfe-history  and  economy. — In  West  and  South  Germany, 
similar  to  those  of  the  common  cockchafer  with  which  it 
swarms,  but  in  smaller  numbers.  In  East  and  West  Prussia 
in  the  midst  of  great  Scots  pine-woods  this  species  alone 
destroys  forests,  the  common  cockchafer  confining  its  attacks 
to  agricultural  lands.  It  does  not  merely  attack  the  horse- 
chestnut  as  its  name  implies,  but  nearly  all  trees.  The 
larvae  are  highly  destructive  to  young  Scots  pines,  3  to  6  years 


210  PROTECTION    AOAINST    INSECTS. 

old,  but  in  their  fourth  summer  they  attack  the  roots  of  poles 
15  to  18  years  old,  and  even  those  of  older  trees.  Season 
for  swarming  somewhat  early  (April).  The  eggs  are  laid  8 
to  14  days  afterwards  10  to  14  inches  deep  in  dry  soil,  but 
in  moist  soil  only  2J  to  4  inches  deep.  The  larvae  appear  in 
July,  and  pupate  in  August  of  the  fifth  year,  about  1^  feet 
deep.  The  chafers  come  out  in  September  and  October,  but 
remain  underground  till  the  next  spring.  A  more  northern 
insect  than  the  common  cockchafer ;  in  Great  Britain  confined 
to  Scotland  and  the  extreme  north  of  England. 

Protective  measures. — Same  as  for  the  common  cockchafer. 


Fig.  11  .—Mehlontha  Fig  78,—Ji/iizotroffiis 

hipjjocastani,  Fabr.  sohtitialis,  L. 


3.  Rhizotrogus  sohtitialis,  L.  {June  chafer), 
a.  Description. 
Beetle  15  to  17  mm.  long,  similar  to  the  two  former,  but 
with  the  abdomen  not  produced  into  a  tail.  Brownish-yellow, 
with  4  raised  carinae  on  each  elytron ;  the  prothorax,  scutellum 
and  underside  covered  with  long  hair.  Antennae  9-jointed, 
the  club  3-jointed.     Claws  with  a  small  tooth  at  their  base. 

//.   Life-liifitory,  elr. 

Similar  to  the  common  cockchafer.  Flight-time  some- 
what later,  in  June  and  July.  The  beetle  attacks  young 
Scots  pine  shoots,  but  prefers  the  beech,  hornbeam,  poplars, 
willows,  etc.  The  larvae  devour  the  roots  of  small  plants 
chiefly  of  grasses  and  grain  crops.  The  insect  is  found  iii 
sandy    soil,  but    is   less    frequent   in   forests   than   the  two 


AGRILUS    VIRIDIS.  211 

preceding  species.     It  is  locally  common  in  many  parts  of 
Great  Britain. 

Protective  rules  and  remedial  measures  as  for  the  common 
cockchafer. 

Family  II. — Buprestidae. 
Descriplion  of  FamUy. 

Imaiios  long  and  slender,  generally  with  hard  elytra  which 
taper  posteriorly,  as  a  rule  brightly  coloured,  with  a  metallic 
lustre.  Antennae  short,  generally  serrate  and  11-jointed. 
Posterior  angles  of  the  thorax  rounded.  Front  and  middle 
pairs  of  coxae  globose,  the  hind  pair  flattened.  Legs  short 
and  weak ;  tarsi  5-jointed.  Abdomen  of 
5  segments,  of  which  the  two  anterior  are 
fused.  The  active  flight  of  these  insects 
generally  takes  place  in  June  and  July  in 
hot  sunshine.  A  generation  usually  lasts 
two  years. 

Larvae  cylindrical  or  flat,  white,  and 
without  legs  ;  the  first  prothoracic  segment 
is   broad.      They 'live   partly  between  the  °  r/nVw,  L. 

bast  and  sapwood  of  young  trees,  partly  in 
the  stumps,  or  in  old  decaying  trees.     They  pupate  in  situ  in 
a  cocoon  made  of  fragments  of  wood.      Flight-holes  of  the 
imagos  transverse  oval,  nearly  half-elliptic. 

The  most  injurious  species  are  found  on  broad-leaved  trees, 
but  in  Germany  a  few  species  attack  coniferous  wood^.  In 
Great  Britain  all  the  species  of  Buprestidae  are  scarce,  local 
and  therefore  unimportant.  The  following  species,  though 
very  rare  in  this  country,  will  serve  to  illustrate  their  life- 
history  and  economy  :  — 

1.  Agrilus  viridis,  L. 
a.  Description. 
Beetle  6  to  8  mm.  long,  very  variable  in  colour,  being  some- 
times olive-green,  bluish-green,  blue,  earth-coloured,  etc. ; 
under  surface  black.  Thorax  broader  than  long ;  the  last 
abdominal  segment  rounded  at  the  extremity  ;  apices  of  the 
elytra  diverging  slightly  from  one  another,  and  finely  dentate. 

p2 


21: 


PROTECTION    AOAINST   INSECTS. 


h.  LIfe-histonj. 

Flight  in  June  and  July,  in  brilliant  sunshine. 
Eggs  laid  either  singly  or  by  twos  and  threes  on  the  bark 
of  smooth  saplings,  especially  at  the  base  of  stems  exposed  to 
the  sun. 

The  larvdc  appear  in  August,  and  live  over  two  winters  before 
jyupatioii,  which  takes  place  in 
April  or  May  of  the  third  summer 
in  a  pupal  chamber  made  in  the 
sapwood  or  bast. 

The  imagos  emerge  in  June  or 
July,  leaving  a  hole  oval  below 
and  straight  above,  thus  :  '^. 

Generation  lasting  two  years  ; 
the  insects  seldom  appear  in  Ifirge 
numbers. 


r.  R(']atio7is  to  the  Forest. 

The  beetle  prefers  young  beech 
plants,  but  also  attacks  alder, 
birch,  oak,  and  aspen,  especially 
weakly  saplings,  generally  stand- 
ing in  the  open,  or  along  the  edge 
of  the  forest.  It  is,  however,  only 
the  larvae  which  are  really  de- 
structive. They  burrow  through 
the  bark  down  to  the  sapwood, 
and  excavate  in  it  a  shallow, 
well-defined  winding  passage, 
sometimes  extending  deeper  into 
the  wood ;  it  increases  in  breadth 
with  the  age  of  the  larvae. 
If  the  plant  be  girdled,  the  upper  part  of  the  stem  dies,  at 
least  in  dry  localities.  The  bark  projects  somewhat  all  along 
the  sides  of  the  passage.  In  the  case  of  saplings  which 
recover,  the  bark  splits,  owing  to  tlie  pressure  of  the  callus 
forming  over  the  wound. 


Figs.  80  and  81.— Injury  caused  to 
beech -saplings  by  A.  riridis,  L. 
(^Xatural  size.) 

a  Larval  gallery,  exposed  by  removal 

of  the  bark. 
b  Old    larval    galleries   exposed  by 

rupture  of  the  bark. 
c  Transverse  oval  flight-holes  of  the 

imago. 


AGRILUS    VIRIDIS. 


213 


(I.  Protective  Rules. 

i.  Care  in  planting  out  saplings,  and  choice  of  strong 
healthy  plants. 

ii.  Smearing  the  saplings  with  a  mixture  of  2  parts  of  clay, 
1  of  lime,  and  1  of  cowdung,  shortly  before  the  flight  of  the 
beetles. 


Fi-  82.- 


Poi)lar-wood  bored  by  Ai/n/ns  s>..i:-//iit(aiHs, 
Ilerbst.     {Nalural  size.) 


e.  Remedial  Measures, 
Pulling-up  and  burning  all  infected  saplings  in  May  and 
the  beginning  of  June. 


'2.  0 titer  Species. 
Other  species  of  A^rilus,  such  as  A.  an(justidas,  111.,  attack 
oak,  hazel,  birch,  and  other  saplings,  and  should  be  treated  in 


214  PROTECTION   ACAINST    INSECTS. 

the  same  manner  as  A.  riridis.     A.  sex-r/xttdtus,  Ilerbst,  is 
common  in  France,  where  it  riddles  the  wood  of  old  poplars. 


Family  III. — Elateridae  (Click-bketles). 
Description  of  Familtj. 

Intaijos  long  and  slender,  hard,  resembling  those  of  the 
former  family  in  general  appearance,  but  usually  Mithout 
metallic  lustre.  Antennae  filiform,  generally  serrate  or  pecti- 
nate (J),  11-jointed.  Prothorax  broad  posteriorly,  its  hind- 
angles  produced  and  acute.  Fore  and  middle  coxae  spheroidal, 
legs  short  and  rather  weak,  tarsi  5-jointed.  Abdomen  of  5 
segments.  When  laid  on  their  backs  they  are  able  to  spring 
up  in  the  air  with  a  clicking  noise,  alighting  on  their  legs. 

Generation,  3 — 4  years ;  length  of  time  in  larval  stage 
probably  dependent  on  supply  of  food,  and  lasting  only  three 
years  when  they  are  well  nourished. 

Larrae  long  and  slender  brownish-yellow  grubs,  termed 
n-ire-ivorms,  with  horny,  flat,  dark  heads.  They  are  lighter 
coloured  below,  and  have  6  legs  and  a  stump-like  tubercle 
serving  as  an  additional  leg  on  the  last  segment  ;  they 
generally  live  underground,  or  in  old  rotten  stumps.  They 
are  omnivorous,  devouring  roots,  rhizomes,  seeds,  fungi, 
decomposing  vegetable  and  animal  matter,  and  even  other 
insects.  They  abound  in  newly  broken-up  pasture,  or  clover 
land,  and  are  most  destructive  to  agricultural  crops,  and  in 
forestry  to  sowings  in  nurseries  and  in  the  forest  of  acorns, 
beech-mast,  maple  or  hornbeam,  and  many  coniferous  seeds, 
and  to  the  roots  and  bases  of  the  stem  of  young  coniferous 
and  broadleaved  plants. 

Piqmtion  underground  in  July.  The  beetles  emerge  a  few- 
weeks  later,  and  may  be  found  on  flowers,  or  under  bark  or 
stones.  Wire-ikvorms  are  the  larvae  of  beetles  of  the  genera 
Elater,  Athous,  Agriotes,  especially  .1. //»m/»s,  which  is  the 
chief  ojflfender,  and  of  other  Klatcridce. 

The  larvae  of  Dolojniis  numiinatns,  L.,  gnaw  the  roots  of 
young  spruce  and  Scots  pine,  and  thus  do  much  injury  in 
nurseries  and  plantations.  Agriotes  Jineatus,  L.,  and  A.  oh- 
seunis,  Gyll,  devour  acorns,  and  also  coniferous  seeds;  Atltoits 


LYMEXYLONIDAfi.  21 5 

haemorrhoidalis,  Fabr.,  beech-mast,  acorns,  hazel-nuts,  and 
seeds  of  hornbeam.  Some  species  also  attack  the  young 
shoots  of  trees,  in  order  to  extract  the  sap.  Lacon  murinus,  L., 
has  been  known  to  injure  the  oak  in  a  similar  way  to  Tele- 
phonts  ohscurus,  L.,  and  certain  species  of  Corymbites  do 
similar  damage,  so  that  the  shoots  become  black,  dry  and 
break  off. 

Protective  rules. — The  conspicuous  brown  larvae  should  be 
collected  and  destroyed  when  nursery-beds  are  dug  up,  and 
turf  in  which  they  are  noticed  may  be  burned.  It  is  imprac- 
ticable to  collect  the  beetles.*  Nursery-land  full  of  wire- 
worms  may  be  dressed  with  gas-lime,  which  should  be  well 
dug  in,  and  the  land  left  without  further  cultivation  for 
6  months.  The  methods  of  destroying  them  are  very  expen- 
sive, requiring  1,000  lb.  of  liquid  bisulphide  of  carbon  per 
acre,  or  10  tons  of  salt.  Eooks,  starlings  and  plovers  devour 
them  greedily. 

Family  IV. — Lymexylonidae. 
Description  of  Family. 

Imaf/os  cylindrical,  long  and  slender.  Elytra  not  curved 
downwards  and  slightly  gaping  at  the  apex.  Antennae  thread- 
like, somewhat  thickened  in  the  middle,  or  serrate,  11-jointed. 
Fore  and  middle  coxae  cylindrical  or  spheroidal.  Tarsi  5- 
jointed.     Abdomen  of  5 — 6  segments. 

Generation  annual. 

Larvae  long,  cylindrical,  soft-skinned,  white,  free  from  hair, 
and  6-legged.  They  are  generally  found  in  logs  of  timber  in 
depots  and  dockyards,  or  in  stems  of  trees.  The  beetles  fly 
round  the  trees  and  timber  in  June  and  July,  and  lay  their 
eggs  in  'cracks  in  the  bark.  Chiefly  dangerous  to  broad- 
leaved  trees. 

Lymexylon  n  a  vale,  L. 
(a)  iJescriptio)!. —  S   8  to  10  mm.  long,  black ;  elytra,  abdo- 
men,   and    legs    yellowish-brown.       ?     12 — 15    mm.   long, 

•  For  an  accouut  of  protective  treatment  against  wireworms,  rido  Miss 
Ormerod  02>.  cif.,  ed.  ii.,  pp.  Ill  to  11.^. 


216  PROTECTION    A(;AINST    INSECTS. 

ochreous.     The   head,  side-margins   and  apex  of   the  eljtra 
are  l)lackish  ;    the  latter  do  not  quite  cover  the  abdomen. 
Larva  white,  with  a  fleshy  hump  on  the  last  segment. 

(b)  Life -hi  story. — The  beetle  flies  on  warm  days  from  the 
beginning  to  the  middle  of  July.  The  eggs  are  laid  on  large 
broken  tree-stumps,  or  on  large  barked  oak  logs,  but  never  on 
sound  standing  trees.  The  larvae  eat  galleries  into  the  wood 
of  about  1  mm.  in  diameter  and  deflected  at  right  angles 
every  few  inches.  The  vertical  burrows  are  somewhat 
crooked,  but  the  horizontal  ones  are  quite  straight.  This 
insect  is  chiefly  injurious  in  timber  depots  and  dockyards. 

In  1746,  Linnaeus  found  the  damage  done  to  oak-timber  in 
the  Gothenburg  harbour  so  great  that  he  exclaimed  how 
wonderful  it  was  that  so  small  a  worm  could  do  yearly  so 
many  thousands  of  dollars'  worth  of  injury.  His  advice  to 
the  King  of  Sweden,  at  whose  command  he  investigated  the 
injury,  was  to  sink  the  affected  timber  under  water  before  the 
flight-time  of  the  insects. 

Lijmcxijhm  is  scarce  and  local  in  Great  Britain,  but  is  liable 
to  be  imported  in  continental  oak-timber. 

(c)  Protective  rules. — Smearing  felled  timber  with  tar,  when 
attacks  are  feared. 

A  similar  species,  Hylecoetus  dermestoides,  L.,  lives  chiefly 
in  the  stumps  of  felled  trees  ;  it  is  locally  common  in  Great 
Britain,  chiefly  in  Sherwood  Forest,  but  has  never  proved  so 
destructive  as  Lymexijlon  to  timber  of  commercial  value. 


Family  V. — Anobiidae. 

iJeseription  of  Family. 

Imayos  small,  cylindrical,  similar  to  bark-beetles,  will 


cowled  prothorax  which  conceals  the  upper  part  of  the  head. 
Antennae  slendgr,  pectinate  or  clubbed,  more  rarely  serrate, 
8  to  11-jointed,  folded  under  the  prothorax  when  the  insect  is 
at  rest.  Fore  and  middle  coxae  cylindrical  or  spheroidal; 
tarsi  mostly  6-jointed,  but  4-jointed  in  the  case  of  many 
species.  Abdomen  with  5  ventral  segments.  Generation 
often  lasting  several  years.  The  beetles  when  disturbed  lie 
motionless  as  if  dead. 


WEEVILS.  217 

Larvae  strongly  curved,  somewhat  square  in  transverse 
section,  whitish,  hairy  and  6-legged.  The  beetles  appear  in 
the  spring  or  early  summer. 

The  beetles  and  larvae  live  chiefly  in  rotten  wood,  partly  in 
standing  trees,  where  they  eat  out  galleries  which  cross  one 
another ;  also  in  the  pith  of  young  pine-shoots,  as  for  instance, 
Ernohius  nif/rimis,  Er. ;  in  spruce  cones,  Anohiion  ahictis, 
Fabr.,  and  others.  They  also  live  in  fungi,  in  the  woodwork 
of  houses,  and  in  furniture,  for  instance,  Anohium  pcvtinax, 
L.,  and  A.  donicsticum,Fom-c.,  a  small  brown  beetle  2  lines  long, 
known  on  account  of  the  ticking  noise  it  makes  as  the  "  death- 
watch." 

Xestohiuni  tcssclatum,  Fabr. 

Imago  5  to  6  mm.  long,  convex,  subcylindrical,  dark-brown, 
very  finely  and  closely  punctured,  and  dappled  with  patches 
of  short  greyish-yellow  hairs. 

The  imago  and  larva  bore  into  and  riddle  the  wood  of 
old  standing  trees  (oak,  beech,  sycamore,  etc.)  and  also  the 
timber- work  of  churches  and  old  houses.  Locally  common  in 
England. 

The  attack  of  Anohiidac  on  trees  generally  begins  at  an  old 
wound,  particularly  on  the  stump  of  a  branch. 

Treatment.  —  The  removal  of  attacked  stems.  Careful 
and  timely  dressing  of  exposed  wounds  and  branch-stumps 
with  tar. 

Family  VI. — Curculionidae  (Weevils). 
Deseription  of  Family. 
Imaijos  small  or  of  medium  size,  with  the  head  produced 
into  a  straight  or  bent  rostrum  or  snout,  at  the  end  of  which 
are  the  small  mouth-parts.  Antennae  nearly  always  elbowed, 
8  to  12-jointed,  with  a  club  of  very  variable  structure ;  their 
basal  joint  is  capable  of  being  folded  into  a  groove  or  serohe 
in  the  snout.  Elytra  broader  than  the  thorax.  Fore  coxae 
spheroidal  or  conical,  hinder  coxae  small  and  transverse. 
Legs  stout,  the  thighs  sometimes  adapted  for  leaping.  Tarsi 
4-jointed,  the  last  joint  but  one  being  generally  heart-shaped, 


218  PROTECTION   AGAINST    INSECTS. 

or  bilol)ed.  Al)domen  of  5  segments,  of  wbicli  the  two  first 
are  generally  larger  and  united.  Many  species  have  no  wings. 
Generation  usually  annual,  but  it  may  last  for  two  years,  or 
two  broods  may  occur  in  one  year. 

Larrac  thick-set,  cylindrical,  curved  ventrally,  the  head 
horny,  the  body  soft-skinned,  wrinkled  and  thinly  hairy, 
whitish  and  without  feet. 

Pupae  recognisable  by  the  conspicuous  snout  and  antennae, 
generally  with  two  posterior  pointed  processes.  The  larvae 
and  beetles  eat  the  roots,  bark,  bast,  wood,  leaves,  blossoms, 
fruits  or  seeds  of  forest  trees. 

There  are  no  galleries  made  by  the  parent  beetles  for  ovi- 
position,  but  the  eggs  are  placed  in  situ  by  means  of  the 
snout.  Some  species  are  very  destructive.  Most  of  the 
beetles  drop  to  the  ground  from  the  plant  at  the  slightest 
shaking. 

1.  Apodcrus  cori/li,  Fabr. 

a.  Drscrijition. 

The  hcctle  is  G  to  8  mm.  long,  bright  red,  with  the  head, 

antennae,  a  median  spot  on  the  prothorax,  and  the  underside 

black.     The  elytra  are  rather  short  and  much  wider  than  the 

narrow  prothorax,  w'ith  rows  of  strong  punctures. 

b.  Life-hisiory,  etc. 
The  $   in  May  cuts  the  leaves  of  various  broadleaved  trees 
by  a  transverse  incision  made  towards  the 
base  and  reaching  the  mid-rib.     She  then 
rolls  the  terminal  part  into  a  thick  cylin- 
drical roll,  in  which  a  single  yellow  egg  is 
laid.     The  larva  feeds  on  the  interior  of  the 
roll,  which  subsequently  becomes  detached, 
and  when  mature  it  pupates  in  the  ground. 
Fig.  83.  —  Oak-leaf,         The  beetle   is  locally  common,   though 
itiM^lt"'''     "^^®^'    abundant,   chiefly   on    hazel,    also 
(Natinai\i:c)         ^^^   alder,  ^oak,    beech    and    hornbeam;    it 
frequents  young  shrubs  and  undergrowth, 
and  in  the  perfect  state  feeds  by  gnawing  holes  in  the  leaves. 


WEEVILS.  219 

When  injurious  it  may  be  collected  by  shaking,  and  the 
rolls  may  be  picked  off. 

Attdahiis  curculio)ioides,  L.,  a  very  similar  insect  with  almost 
smooth  elytra,  is  locally  common  on  oak  and  sweet-chestnut, 
chiefly  on  undergrowth. 


2.  Rhynchitcs  hetulae,  L. 
a.  Description. 

This  hectic  is  4  to  5  mm.  long,  black  and  slightly  hairy ; 
rostrum  hardly  longer  than  the  head ;  elytra 
broad  with  deep  coarsely  punctured  striae; 
posterior  femora  strongly  dilated  in  the  3  . 


h.  Life-historij,  etr. 
The  ?  in  May  cuts  the  leaves  of  birch 
and  other  trees  on  both  sides  down  to  the 
mid-rib  in  a  curved  line,  beginning  near  the 
base  of  the  leaf ;  she  lays  an  egg  on  the  edge 
of  the  leaf  in  a  little  pocket  made  in  the  leaf 
by  removal  of  a  bit  of  its  epidermis,  and  then 
rolls  up  the  two  sides  over  one  another,  so  Fig.  84.— Uirch- 
that  the    gg  lies  in  the  middle  of  the  roll,        leaf,  rolled  up  by 

1  •   1     •  ^  1     .u         1  '  R.  hetulae,  L. 

which  IS  open  at  both  ends.  ,  Yaturai  «/-<• ) 

The  larva  feeds   on  the   roll,  and  in  the 
autumn  falls  to  the  ground  with  it,  and  pupates  in  the  soil. 

The  beetle  prefers  the  birch,  on  which  species  thousands  of 
these  rolls  may  be  found;  but  it  also  attacks  beech,  poplars, 
alder,  hazel,  etc.  It  is  common,  and  widely  distributed  in 
Britain, 

r.  Protective  Rules. 

The  rolls  may  be  collected  and  destroyed. 

R.  bctuleti  is  very  destructive  to  vines,  and  also  attacks 
many  broadleaved  trees,  as  bir^i  and  hazel ;  and  R.  popuU, 
L.,  attacks  poplars  and  aspens.  Both  are  local  in  Great 
Britain. 


220  PROTECTION   AGAINST   INSECTS. 

3.  Stro2)]ios()mns  cori/li,  Fabr. 

a.  JJescripiion. 

The  beetle  is  4  to  0  mm.  in  length,  short  and  thick,  with 
the  elytra  convex  and  subspherical ;  covered  with  close-lj'ing 
mottled  brownish-grey  scales,  except  over  the  base  of  the 
suture,  which  is  black  and  bare  ;  prothorax  with  a  fine  median 
furrow  ;  antennae  and  legs  ferruginous. 


b.  Life-liistori/,  elc. 

Pairing  takes  place  in  June,  and  oviposition  follows  on 
small  roots  near  the  surface  of  the  soil.  The  larvae  lie  under 
the  surface-covering,  especially  in  dry  places,  pupating  in  July 
and  the  beginning  of  August.  The  perfect  insects  are  dis- 
closed in  August  and  September.  They  are  wingless,  and 
ascend  trees  by  climbing,  beginning  in  early  spring  to  feed  on 
the  needles  and  bark  of  young  pines  and  spruce  (by  preference 
about  two  years  old).  This  insect,  which  is  abundant  both 
in  conifer  woods  and  in  those  of  broadleaved  trees,  is 
occasionally  very  injurious. 


c.  Protective  Rules. 

Thorough  grubbing-up  of  stumps  and  root-stocks ;  employ- 
ment in  cultivations  of  well- grown  and  not  too  young  plants  ; 
trap-ditches ;  the  collection  of  the  beetles  in  August  and  Sep- 
tember under  pieces  of  bark  on  the  ground,  which  are  kept 
down  wdtli  stones  and  visited  daily.  Collection  of  the  perfect 
insects  from  the  plants  by  shaking,  which  should  be  done  in 
the  spring ;  the  beetles  drop  readil3\ 

*S'.  uhestis,  Marsh.,  and  S.  Uinhatns,  Schonh.,  are  allied  species 
of  similar  appearance  and  habits. 

Various  other  species,  as  Sitojies  lineatas,  L.,  and  the  Phjjl- 
lohii,  weevils  covered  with  bright  or  dull  green  scales,  also  eat 
buds  and  shoots,  chiefly  of  broadleaved  trees.  The  usual 
treatment  is  the  collection,  iTy  shaking,  of  the  insects  at  the 
time  of  the  injury. 


WEEVILS. 


221 


4.  Balaninus  micum,  L.  {Nut-iceevil). 
a.  Description. 

Beetle  6  to  8  mm.  long,  oval ;  black  and  covered  with 
yellowish-grey  hairy  scales.  Rostrum  very  long,  thin  and 
curved,  reddish-brown.  Legs  dark  rust-brown,  with  greyish- 
yellow  hairs. 


1).  Life-history,  etc. 

The  beetle  pierces  hazel  and  other  nuts  with 
whilst  the  shell  is  still  green,  from  May  to 
July,  making  in  each  nut  a  single  hole  as  if 
pierced  by  a  needle,  in  which  an  egg  is  laid. 
The  larva  (maggot)  eats  about  half  the  kernel 
of  the  nut,  and  falling  to  the  ground  with 
the  ripe  fruit  in  autumn,  gnaws  its  way  out 
of  the  shell,  and  pupates  in  the  earth  till 
next  spring.  The  perfect  insect  emerges  in 
the  summer.  Worm-eaten  nuts  may  be 
distinguished  by  either  of  the  holes  in  them. 

The  species  is  common  and  may  diminish 
the  seed  yield.  An  allied  species,  B.  [ilandium, 
Marsh.,  chiefly  attacks  acorns. 


its  proboscis. 


nut,    bored     by 

J},  nueum,  L. 

(^Xatural  size.) 
a  Hole  made  by  the 

parent  beetle. 
b  Exit  -  hole       of 

larva. 


c.  Protective  Elites. 
Collection  and  destruction  of   the  nuts  which  fall  earliest 
(those  infested  with  larvae).    Collection  of  the  beetles  by  shak- 
ing.    Titmice  attack  the  green  nuts  to  reach  the  larvae. 


5.  Orchestes  fcic/i,  Gyll. 
a.  Descrijttion. 
he  Beech  leaf-miner  beetle  is  2*5  to  3  mm.  long ;  black, 
with  fine  grey  hairs.  Elytra  with  striae  of  conspicuous,  coarse 
punctures  ;  rostrum  depressed  under  the  body  ;  antennae  and 
legs  bright  brown.  Hind-legs  adapted  for  leaping,  their 
femora  thickened  and  furnished  with  a  small  tooth  before  the 
apex. 


222 


PROTECTION    AGAINST    INSECTS. 


I>.  Life-history,  dr. 
The  $  lays  her  eggs  one  by  one  on  the  under  surface  of  unde- 
veloped beech  leaves,  etc.,  biting  holes  for  the  purpose  under 
the  epidermis,  near  the  mid-rib.  The  larva  hatches  in  the 
month  of  May  and  bores  in  the  leaf-parenchyma  either' 
towards  the  terminal  point  of  the  leaf,  or  sideways,  forming  a 
winding  tunnel  which  continually  increases  in  size  till  it 
becomes  a  large  patch.  The  parts  which  have  been  eaten,  at 
first  whitish,   become   finally  brown.     Pupation  takes    place 


Fig.  86.— Beech -leaf  attacked  by  O.fagi,  Gyll.     (^Nahiral  size.) 
a  Commencement  of  larval  mine  by  a  gallery,  which  widens  at  b  into  an  irregidar 
space,     c  Pupa  in  a  bladder-like  cocoou.     d  Holes  of  various  si/cs  gnawed  by  the 
beetles. 

near  the  border  of  the  leaf,  between  the  upper  and  lower 
epidermis  of  the  area  which  has  been  eaten  by  the  larva. 

In  June  the  beetle  emerges,  and  passes  the  winter  under 
the  dead  leaves  on  the  ground. 

When  the  larvae  of  this  insect  are  abundant,  the  foliage  of 
the  beech  trees  appears  reddish-brown,  just  as  if  it  had  been 
frozen  by  a  late  frost. 

The  beetle  shortly  after  emergence  has  been  known  to  feed 
on  various  substances  ;  for  instance,  fruit  (cherries,  raspberries, 
goosebei'ries),  cauliflowers ;  it  also  pierces  the  capsules  of  beech 
nuts,  causing  them  to  open  before  the  seed  is  ripe.  In  the 
early  summer  it  riddles  the  beech  leaves  with  small  holes,  and 
gnaws  the  female  flower-buds. 


WEEVILS. 


223 


The  insect  attacks  woods  of  all  ages,  but  prefers  old  to 
young  growth,  and  especially  trees  bordering  the  wood,  or 
isolated  trees,  as  shelter  trees  in  a  regeneration  felling.  It 
appeared  in  the  Palatinate  in  1869  in  such  numbers  that  in 
Qiany  beech  woods  scarcely  a  leaf  was  left  uninjured.  In  the 
Spessart,  in  1888,  the  beetle  seriously  reduced  the  rich  beech- 
mast.  In  1808,  the  beech  leaf -miner  was  extremely  abundant 
in  beech  woods,  all  over  Germany.  It  is  common  in  Great 
Britain.  No  protective  measures  other  than  the  encourage- 
ment of  insectivorous  birds  are  practicable.  The  beetle  is  too 
active  to  be  captured  in  numbers. 


6.  Orchestcs  quercus,  L. 

Beetle  reddish-yellow,  covered  with  grey  hair,  and  with  black 
eyes  and  breast,  hinder  thighs  with 
serrate  teeth.  It  attacks  the  oak 
just  as  the  preceding  beetle  attacks 
the  beech.  It  is  commonest  on 
suppressed  oak  undergrowth,  under 
Scots  pines,  etc. 

7.  Cryptorrlnjnchus  lapathi,  L. 
a.  Descrijition. 

Beetle  7  to  8  mm.  long,  and  very 
characteristically  coloured ;  thorax 
and    the    basal    two-thirds    of    the 

elytra  dark  brown  or  black,  with  patches  of  erect  black  scales ; 
flanks  of  the  thorax,  the  anterior  part  of  the  under  surface, 
the  apex  of  the  elytra  and  the  femora  thickly  covered  with 
white  scales.  The  rostrum  can  be  folded  into  a  furrow  under 
the  thorax. 


Fig.  87. — Cryptorrhynehus 
htpathi,  L. 


l.  Life-ltisiory. 

The  beetle  flies  at  the  end  of  April  and  in  May.  The  eggs 
are  laid  in  May,  in  small  holes  gnawed  in  the  bark  of  the 
stem,  or  of  the  branches  of  alders,  etc. 

The  larvae  appear  14  days  later,  in  May  or  June,  and  pupate 
as  a  rule  in  autumn  in  their  galleries.     The  beetle  emerges  in 


224 


PROTErTION    AGAINST    INSECTS. 


autumn,  and  passes  the  winter  in  these  galleries  or  under 
moss  ;  but  occasionally  its  emergence  is  deferred  till  the 
spring.     Generation  annual,  sometimes  lasting  2  j-ears. 

c.  Rehffmis  to  the  Forest.  , 

The  hlack  and  white  alder  are  preferred  by  it,  then  willows ; 

but  poplars  and  birch  are  also  attacked.      If  attacking  alder  it 

selects  young  stems  (2  to  4 
years  old),  but  older  trees  in 
the  case  of  willows.  It  is 
therefore  more  dangerous  to 
the  alder,  and  especially  the 
black  alder.  Willow-cuttings 
are  also  attacked  without 
respect  to  species,  and  care- 
less coppicing  giving  rise  to 
gnarled  stools  increases  the 
danger  of  infestation. 

The  insect  is  injurious  both 
as  a  larva  and  imago. 

The  beetle   eats  the   bark 

of  young  annual  shoots  down 

to  the  sap-wood.     The  larva 

then  gnaws  under  the  bark, 

and  bores  obliquely  upwards 

or  downwards  into  the  wood 

and  often   to   the   pith,  thus 

ruining     the    young    stems, 

which  die  or  break  oflf  (Figs. 

88   and   89);    in   the    latter 

figure   the    galleries    of    the 

larvae  have  l)een  exposed. 

The  attack  is  indicated  by  discoloration  and  swelling- up  of 

the  bark,  and  later  on  by  its  depression  over  the  points  of 

injury,  and  by  the  brown  wood-dust  which  is  ejected  from  the 

burrows,  or  has  fallen  to  the  ground. 

The  beetle  attacks  and  kills  isolated  stems  along  the  banks 
of  streams  where  the  localities  are  not  too  dry,  and  since 
1830,  it  has   been   common   near   Tharand   in   Saxony.     In 


Figs.  88   and   89.  —  Larval  burrows  of 

C.  hipathi,  L. ,  in  Alder  stems. 

(^Natural  size.') 


PINE- WEEVIL.  225 

Britain  it  is  somewhat   local,  though  not  uncommon  where 
it  occurs. 

d.  Frolectii'e  Rules. 
"    Infested  plants  and  coppice-shoots  should  be  cut  down  by 
the  end  of  July  and  burned. 

The  beetles  should  be  knocked  off  the  trees  on  to  cloths. 
This  should  be  done  carefully,  as  the  slightest  shaking  of  the 
trees  induces  the  beetles  to  fall  and  lie  as  if  dead  on  the 
ground,  where  they  may  escape  observation. 


Vi 

/i 

Fig.  90. — Ilylohins  abicii.f,  Fabr. 
a  Imago.         b  Larva.        c  Pupa. 


8.  Hijlohlus  abictii^,  Fabr.   {Pine -ice evil).* 

a.  Dcscriplion. 

Beetle  8  to  13  mm.  long,  of  strong  build,  pitchy-brown,  with 
2  or  3  golden  (rarely  pale  yellow)  irregular  stripes  across  the 
elytra,  and  a  few  spots  of  the  same  colour  near  their  apex. 
Head  with  a  strong,  somewhat  curved  rostrum,  thorax 
gradually  narrowed  from  the  middle  to  the  apex,  with  coarse 
confluent  punctation  and  a  slightly  elevated  median  ridge, 
clothed  w  ith  patches  of  thick  hair ;  elytra  thrice  as  broad  as 
the  base  of  the  thorax,  and  somewhat  elevated  at  the  shoulders. 
Legs  brown,  the  femora  toothed  below  (by  which  it  may  be 
distinguished  from  Pissodes  pini,  L.,  which  otherwise  greatly 
resembles  it),  and  generally  darker  than  the  tibiae. 

*  The  most  valuable  account  of  this  very  destructive  forest  insect  is  by 
Oberforster  von  Oppcn,  "  Untersuchungen  liber  die  Generationsverhaltnisse  des 
IIijl.  ahictia."     "  Zeitschr.  fr.  Frst.  u.  Jgdw."  188.J,  pp.  SI  ami  14L 

F.P.  ■  Q 


226 


PROTECTION    AGAINST    INSPECTS. 


The  chief  swarming 


Fig.  yi. — Scots  piue  root 
bored  by  H.  ahietis,  L. 

a  Boring  free  from  wood- 
dust. 

b  Boring  full  of  wood-dust. 

c  Loiigitudiual  suction  of 
pupal  chamber. 

d  Transverse  section  of 
pupal  chamber. 

c  Flight  hole. 

/  Entrance  to  pupal  cham- 
ber closed  with  bitten 
wood. 


h.  TAfe-histnri/. 

period  of  this  beetle,  which  Uves  from 
1  to  2  years,  is  in  the  spring  or  early 
summer  (May  or  June)  ;  but  jmiring 
and  reproduction  go  on  throughout  the 
whole  of  the  warmer  season  up  to  Sep- 
tember, so  that  no  real  period  for 
swarming  exists.  Copulation  generally 
takes  place  on  the  ground. 

Tlie  eggs  are  laid  from  May  to  Sep- 
tember on  stumps  and  roots  of  the 
Scots  pine  and  spruce,  preferably  on 
those  of  trees  felled  about  18  months 
before.  The  under-surface  of  roots — 
and  especially  of  those  ^Yhich  project  out 
of  the  ground  —  is  preferred.  Hiber- 
nating beetles  continue  egg-laying  in 
the  spring. 

The  larvae  appear  after  2  to  3  weeks, 
and  up  to  the  middle  of  October  eat  gal- 
leries sometimes  a  metre  long  (Fig.  91) 
in  the  bast  and  sap  wood  of  the  stumps 
and  roots  ;  the  burrows  continually 
increase  in  breadth,  and  are  tilled  with 
wood-dust.  The  larvae,  at  least  those 
which  have  been  hatched  in  the  autumn, 
pass  the  winter  at  the  end  of  these 
galleries.  They  do  no  injury  of  any 
economic  importance,  their  sources  of 
food  being  confined  to  valueless  wood. 

In  the  follow  ing  spring,af  ter  having  been 
dormant  for  about  9  months,  the  larvae 
pupate  in  the  stump  or  roots,  in  a  cocoon 
constructed  of  wood-fibres  and  boring- 
dust.  The  pupal  state  lasts  about  2  to  3 
weeks.  The  perfect  insects  emerge  from 
May  till  September  of  the  second  year. 
The  period  of  disclosure  thus  extends 
over  four  months,  corresponding  to  the 


riNE-WEKVIL.  227 

season  of  pairing.  Those  beetles  which  emerge  during  the 
autumn  do  but  Httle  injury,  as  they  do  not  appear  in  such 
numbers  as  in  the  spring ;  except  for  a  few  belated  individuals, 
they  proceed  at  once  to  coi^ulate.  Nearly  the  whole  summer 
through  both  larvae  and  imagos  may  be  found.  The  latter 
pass  the  winter  under  moss,  dead  leaves,  in  the  ground,  in 
hollow  stumps,  under  stacks  of  wood,  etc.  Von  Oppen  found 
that  they  prefer  to  winter  in  dense  thickets  of  10-  to  15-year- 
old  plants  rather  than  in  older  woods. 

The  generation  lasts  generally  one  year  only,  but  may 
extend  to  15  months  ;  only  under  very  favourable  climatic 
circumstances  can  it  be  less  than  a  year. 

The  beetle  frequently  appears  in  extraordinary  numbers  on 
felling-areas,  where  it  is  bred,  and  in  plantations  which  it 
destroys.  It  is  very  common  in  most  pine  woods  throughout 
Great  Britain. 

It  rarely  if  ever  flies,  moves  slowly  along  the  ground,  and 
in  times  of  great  heat  or  cold  conceals  itself  in  grass,  refuse  of 
felled  trees,  earth,  etc. 

c.  Relations  to  the  Forest. 

This  species  is  important  in  the  perfect  state  alone,  by  the 
injuries  it  inflicts  on  young  coniferous  plants;  weakly  Scots 
pine  and  spruce  of  3  to  6  years  old  are  preferred,  but  younger 
plants,  even  yearlings,  are  attacked,  and  exceptionally  other 
conifers  (black  and  Weymouth  pines,  Douglas  fir,  silver-fir 
and  larch).  Even  broadleaved  trees  are  attacked,  chiefiy 
oaks  and  other  species  planted  in  old  coniferous  woods,  or 
employed  as  a  shelter-wood  for  Scots  pine.  The  insect  is 
therefore  clearly  polyphagous. 

The  damage  is  done  from  May  to  September,  the  Ijark  of 
the  young  plants  being  gnawed  all  along  the  stem,  down  to 
the  rootstock.  The  bast  or  sapwood  is  exposed  in  patches, 
which  may  be  as  large  as  a  bean,  and  resin  exudes  from  the 
torn  walls  of  the  points  of  attack.  More  of  the  outer  bark  is 
always  removed  than  of  the  bast,  so  that  the  injuries  appear 
as  irregular  and  shelving  erosions  of  the  surface. 

Frequently  in  this  way  the  young  trees  are  girdled,  and 
very  small  plants  are  completely  peeled,  up  to  their  crown. 

(4  2 


228 


PROTFXrnON    AGAINST    INSECTS. 


In  tlie  case  of  the  Scots  pine  the  attacks  of  the  beetle  cause 
the  development  of  numerous  shoots  from  dormant  buds  ;  the 
spruce  is  sooner  killed  than  the  pine. 

On  plants  over  six  years  old,  only  those  parts  from  1  to  5 
years  old  are  attacked,  as  the  six-year-old  bark  is  too  hard  for 
the  insect. 

The  damage  done  is  much  greater  in  the  spring  than  late  in 
the  summer  or  in  the  autumn. 


Figs.  92,  93,  aud  94. — Yoiiiij,'  spruce  plants  guawed  by  II.  ahiclis,  Fabr.     (Xatnral 
size.)     In  Fig.  94,  a  indicates  the  gnawed  parts,  b  those  still  covered  with  bark. 


Freshly  planted,  extensive,  sunny  clearings  near  old  woods 
are  preferred  by  the  beetle ;  especially  those  in  which  the 
stumps  have  been  left  in  the  ground,  or  not  thoroughly 
extracted.  The  beetle  does  not  appear  at  altitudes  over  3,000 
to  3,300  feet. 


(I.  JVo/eriive  Rules. 

The  best  means  of  prevention   consist  in    supplying  this 
destructive  insect  with  as  little  opportunity  as  possible  for 


PINK-WEEVIL. 


229 


breeding,  in  order  to  prevent  its  swarming  in  certain  localities 
in  the  spring.     The  following  are  recommended  : — 

i.  Establishment  of  small  feeding-areas,  as  if  these  are 
extensive  the  reproduction  of  the  beetle  is  greatly  facilitated. 

Care  must,  however,  be  taken  not  to  go  too  far  in  sub- 
dividing the  felling-areas,  as  each  area  is  a  breeding  place  for 
weevils. 

ii.  Interruption  in  the  order  of  successive  fellings,  so  that 
when  a  felling  has  been  made  no  adjoining  area  shall  be  felled 
till  after  the  lapse  of  3  to  5  years.  In  this  way  fresh  breeding 
material  is  not  afforded  close  to  that  of  the  previous  year. 


Wind 


W 


(lirectiou. 


Direction  ofWHiig. 


Fig.  9o. — An-angemeut  of  fellings  as  described  in  ii. 
X.  E.  S.  W.     Toints  of  compass. 

Fig.    95    shows  such  a   distribution  of   felling-areas,    where 
fellings  in  adjoining  areas  come  every  three  years. 

iii.  Timely  and  complete  extraction  of  stumps  and  roots 
from  felling-areas  in  coniferous  forests,  in  order  to  reduce  as 
much  as  possible  the  number  of  breeding  places  for  the  2  . 
This  is  the  most  effective  measure  of  all.  The  extraction  of 
the  stumps  must  begin  with  the  felling  and  be  finished  by  the 
commencement  of  the  next  winter.  It  is  better  to  grub  up 
the  trees  with  the  roots  attached  than  to  fell  the  trees  first  and 
then  extract  the  stumps  and  roots,  and  the  former  method  has 
been  followed  for  many  years  in  Hesse  and  Nassau  with  very 
good  results  as  regards  the  diminution  of  the  numbers  of 
weevils. 


230  PROTECTION   AGAINST   INSECTS. 

iv.  The  fellinj^-areas  should  he  rapidly  cleared  of  all  refuse, 
and  all  sickly  and  dominated  undergrowth  should  he  removed 
before  the  area  is  planted  up,  as  such  growth  affords  very 
favourable  shelter  for  the  weevils. 

V.  It  has  been  proposed  by  Heyer  and  other  authorities 
that  planting  should  not  be  attempted  until  one  or  two  years 
after  the  felling.  By  this  time  it  is  hoped  the  remains  of  the 
roots  will  have  dried  up  and  become  unsuitable  for  breeding 
places.  Dr.  Hess  considers  that  this  involves  too  great  a 
sacrifice  of  time  and  interest  on  capital,  even  if  it  avoids  the 
necessity  for  replacing  50  per  cent,  of  the  plants,  and  also 
that  the  consequent  deterioration  of  the  soil  entails  more 
expense  than  the  cost  of  replanting  the  failures.  He  estimates 
that  an  interval  of  at  least  3  years,  instead  of  1  or  2  years, 
is  requisite  to  cause  the  roots  to  dry  up  and  become  incapable 
of  serving  any  longer  as  breeding  places. 

vi.  Strong  transplants  should  be  used,  together  with  1  to  2 
years'  temporary  field  crops.  Ball  and  mound  planting  are 
recommended,  and  Nordlinger  prefers  autumn  planting,  as  the 
plants  are  less  liable  than  those  put  in  in  the  spring  to  attacks 
by  the  weevils.  Temporary  field-crops  involve  a  thorough 
working  of  the  soil,  and  this  requires  complete  eradication  of 
the  roots  of  the  former  crop  of  trees. 

In  Saxony,  wherever  there  is  danger  of  an  attack  of  weevils, 
sowing  in  patches  is  preferred  to  planting. 

vii.  The  plants  may  be  dipped  in  a  mixture  of  chalk  and 
water,  up  to  half  their  length,  before  being  planted.  This, 
near  Coblentz,  cost  Is.  Gd.  per  1,000  plants  and  proved 
successful.  Plants  in  situ  may  also  be  dressed  with  cater- 
pillar grease  at  the  rate  of  500  plants  per  day's  work  of  ten 
hours.  The  operator  makes  with  his  linger  a  small  trench 
round  each  plant,  greases  the  stem  and  top  of  root,  and  then 
heaps  the  earth  again  around  the  plant. 

viii.  Broadleaved  trees  may  be  mixed  with  the  conifers. 

ix.  Sheep  may  be  fed  over  the  felling-area,  as  their 
droppings  are  obnoxious  to  the  beetles. 

X.  Protection  of  insect-enemies :  the  fox,  rook,  crow,  jay, 
starling,  etc.  The  Nematoid  worm,  Alhwionema  ininiJnle, 
is  parasitic  on  this   weevil.      It    lives    in    the    abdomen    of 


PINE-WEEVIL.  231 

the  beetle  and  produces  living  young.  They  come  out 
and  grow  in  the  ground  into  a  form  of  lihahditis  that 
lays  eggs.  The  worms  from  these  eggs  eventually  enter  the 
IIyloi)itis. 

c.  EemedutJ  Measures. 

i.  Trenches  to  trap  the  beetle  should  be  dug.  These  may 
be  utilised  either  for  isolating  the  plantations,  or  merely  for 
catching  the  beetles.  The  isolating  trenches  are  dug  round 
the  felling-areas  early  in  spring  in  order  to  separate  them 
from  neighbouring  cultivations,  and  to  collect  the  beetles 
which  may  appear  within  their  radius.  The  other  class  of 
trenches  for  trapping  the  insects  is  dug  within  the  felling- 
areas.  If  this  plan  is  followed,  all  cultivations  are  isolated. 
The  trenches  must  be  kept  in  order,  and  repaired  after  rainy 
weather ;  all  beetles  which  are  found  in  them  should  be 
collected  daily  and  crushed.  As  many  as  1,200  beetles  have 
been  found  in  one  of  the  holes  made  ten  metres  apart  in  such 
trenches. 

Unfortunately  these  very  effective  measures  are  not  always 
possible,  for  instance  in  stony  or  very  loose  ground,  or  on 
steep  slopes.  The  dimensions  for  the  trenches  are  given  on 
p.  175. 

ii.  Artificial  breeding-material  may  be  supplied  in  June,  in 
the  form  of  smooth-barked  pine  or  spruce  poles  3  to  5  feet 
long  and  2  to  4  inches  thick,  cut  when  in  full  sap  and  buried 
in  the  ground  at  intervals  of  30  paces  apart,  obliquely,  so  that 
one  end  is  10  in.  deep  in  the  ground,  and  the  other  about  1 
or  2  in.  above  the  surface.  In  order  that  the  bark  may  be 
preserved  intact,  the  holes  must  be  dug  beforehand  and  the 
pieces  of  wood  placed  in  them  and  covered  with  earth  and 
sods,  which  should  be  slightly  trodden  down. 

These  traps  should  be  placed  both  the  years  before  and  after 
a  felling  in  the  felling-areas,  but  are  useless  in  cultivations ; 
they  should  be  carefully  pulled  out  in  September  and  October 
and  burned,  so  as  to  destroy  the  larvae  they  contain,  and  in 
order  that  none  of  them  may  be  overlooked,  they  should  he 
placed  regularly,  or  a  small  stick  should  be  stuck  in  the  ground 
by  each  of  them. 


232  PROTECTION  AOAINRT    INSECTS. 

The  principle  involved  is  to  provide  r/r/{AVm/ breeding-places 
on  areas  where  by  careful  contraction  of  stumps  natural 
breeding-places  are  about.  The  larvae  are  thus  fixed  in  definite 
localities,  where  they  can  easily  be  destroyed.  Van  Oppen  in  (5 
years  (1886 — 1891)  protected  268  acres  of  felling-area  in  this 
way,  and  on  1,373  poles  found  91, 100  larvae,  the  cost  being  "kL 
per  acre,  or  l\d.  per  pole. 

iii.  Traps  made  of  pieces  of  bark  lying  on  pieces  of  cloth 
may  be  distributed  about  the  felling-areas  and  cultivations 
between  the  months  of  April  and  September,  and  must  be 
renewed  two  or  three  times  during  this  period  as  they  become 
dry  and  cease  to  attract. 

The  best  size  is  from  12  to  16  in.  long  X  6  to  8  in.  wide. 
They  are  placed  with  the  bast  downwards  and  sometimes 
several  one  over  the  other,  and  pressed  down  with  clods  or 
stones  to  keep  them  moist.  They  must  be  searched  daily  for 
the  beetles.  From  25  to  50  are  required  per  acre,  according 
to  the  abundance  of  the  insects.  Coniferous  bark,  and,  by 
preference,  that  of  the  Scots  pine,  should  be  used. 

Children  collect  the  })eetles  better  and  at  a  cheaper  rate  than 
adults.  It  is  a  good  thing  to  place  fresh  pine  twigs  from  the 
youngest  shoots  under  the  bark  to  attract  the  beetles,  which 
will  be  found  eating  these  twigs  when  the  bark  is  lifted  up. 

Wide  flattish  bottles  containing  a  mixture  of  acetic  acid, 
wood-tar  and  turpentine  may  be  placed  in  the  ground,  the 
tops  level  with  the  surface  and  covered  by  a  piece  of  bark. 
The  beetles  are  attracted  by  the  smell,  creep  under  the  bark, 
and  fall  into  the  bottles. 

iv.  Cultivations  may  be  searched  over  for  beetles  by 
children  or  labourers  engaged  in  plantation  work  just  before 
the  midday  or  evening  rest,  with  good  results,  and  at  a  very 
slight  expense. 

The  above  remedial  measures,  if  steadily  pursued,  will  render 
the  attacks  of  these  insects  of  no  importance.  The  beetles 
should  be  killed  by  crushing  on  a  hard  surface  or  by  scalding. 

In  Germany,  J[i/lohms  innastri,  Gyll,  a  smaller  species  of 
weevil,  does  similar  damage  to  that  caused  by  H.  ahietis,  and 
should  be  dealt  with  in  the  same  manner.  II.  pineti,  Fabr., 
attacks  young  larch  in  like  manner.     Neither  is  British. 


PISSODES    NOTATUS. 


233 


9.  Pissndes  notafns,  Fal)i'. 
tf.  Deary ipHon. 
Beetle  7  to  8  mm.  long,  of  a  reddish-bi-own  colour,  and 
irregularly  sprinkled  with  bright-coloured  squamous  hairs  ; 
prothorax  with  about  8  yellowish-white  spots,  its  hind-angles 
acute;  elytra  with  impressed  lines  of  punctures  and  two  broad 
ferruginous  or  whitish  bands,  the  anterior  one  interrupted  at 
the  suture. 

h.  Life-history. 

Period  of  jlight :  April,  May  and  June.      The  eggs  are  laid 
in  the  two  latter  months,  generally  on  the  stems  of  young 


Fig.  9G. — Fissofles  notatus,  Fabr. 
a  and  b  Imago.        c  Larva.        d  Pupa. 

coniferous  plants  and  preferably  on  the  lowest  internodes,  but 
also  on  the  trunk  or  roots  of  older  plants,  on  felled  trees  and 
stacks  of  lirewood,  and  on  cones. 

The  larrae  appear  3  or  4  weeks  afterwards,  in  June  and  July, 
and  live  between  the  bark  and  wood,  pupating  in  their  burrows 
at  the  beginning  of  August. 

The  beetles  emerge  from  the  middle  of  August  to  tlie  end  of 
September,  and  hibernate  at  the  roots,  between  cracks  in  the 
bark,  under  moss,  litter,  or  in  the  ground. 

Larvae  and  pupae  of  this  insect  may  also  be  met  with  during 
the  winter,  and  the  beetles  from  these  appear  in  the  spring. 
Generation  single.  The  insect  is  widely  spread,  but  less  com- 
mon than  Ihjlohius.      This  is  decidedly  the  case  in  Britain, 


234 


PROTECTION    AGAINST   INSECTS. 


"*>  ti 

Fig.  97. — Cocoons 
of  P.  notaUts, 
Fabr.,  on  the 
stem  of  a  young 
pine.  In  the 
portion  covered 
with  bark  a 
square  aperture 
has  been  cut, 
under  which  is 
a  flight-hole. 
{Natural  size.) 


Fig.    flS.  —  Tine- 
cone  from  which 
J'.}io(atus,FnhT., 
has  been  bred. 
{Nuttcral  size.) 


where   P.  iwtatits   is   almost   confined  to  the 
conifer  woods  of  Scotland. 

r.  Relations  lo  ihn  Forest. 
The  beetle  in  May  or  June  pierces  the 
bark  of  Scots  and  black  pines,  more  rarely 
that  of  the  Weymouth  pine,  spruce  or  larch, 
near  the  rootstock  down  to  the  bark  and  sap- 
wood,  partly  to  feed  on  the  sap,  and  partly  to 
lay  its  eggs  there.  It  prefers  4-  to  8-year-old 
plants,  but  also  attacks  poles  up  to  30  years 
of  age.  The  perforations  resemble  fine  needle 
holes,  and  are  very  numerous. 

The  larvae  eat  their  way  between  the  wood 
and  bark  in  descending,  slightly  winding,  and 
constantly  broadening  passages,  which  become 
filled  with  wood-dust ;  at  the  extremity  of  the 
burrows  they  construct  oval  cocoons  made  of 
wood-fibres,  out  of  which  the  l)eetle  bores  its 
way. 

The  insect  is  more  destructive  in  the  larval 
stage.  Plants  which  are  attacked  may  be 
recognised  in  July  by  small  drops  of  turpen- 
tine on  the  bark,  and  by  the  reddening  and 
eventual  death  of  the  needles.  If  it  has  not 
been  girdled,  a  few  green  twigs  may  still  be 
noticed  on  the  wilting  plant. 

The  larvae  also  live  in  the  younger  cones, 
often  two  or  three  together.  Later  on  these 
cones  become  yellowish-grey,  and  may  be 
recognised  by  the  circular  exit  hole  of  the 
beetle,  which  is  about  the  size  of  No.  G  or 
No.  7  shot. 

it.   Prolcciiro  L'liJcs. 
i.  All   sickly  plants  and  dominated  stems 
should  be  removed. 

ii.  All   rootstocks   should    be   grubbed    up, 
and  all  felling  areas  rapidly  cleared, 
iii.   Woodpeckers  should  be  preserved. 


BARK-BEETLES.  235 

e.  Remedial  Measures^. 

i.  Young  plants  containing  larvae  should  be  pulled  up  and 
burned  in  June  and  July. 

ii.  All  poles  which  have  been  attacked  should  be  felled  and 
barked. 

iii.  Billets  of  unbark(  d  fir- wood  should  be  laid  about,  as  for 
JL  ahictis,  in  order  to  attract  the  beetles  for  egg-la3'ing.  They 
should  be  removed  from  the  middle  of  June  to  the  middle  of 
July  and  burned. 

iv.  Cones  attacked  by  the  insects,  and  recognisable  by  the 
exuding  turpentine,  should  be  collected  and  burned. 

10.  Other  Species  of  Pissodes. 
Another  species,  Pissodes  pini,  L.,  attacks  almost  every 
species  of  pine  and  also  young  spruce  in  a  similar  manner  to 
P.  notatus.  In  Great  Britain  it  is  confined  to  Scotland,  where 
it  is  locally  common.  It  is  a  rather  larger  insect,  with  the 
anterior  fascia  on  the  elytra  reduced  to  a  few  pale  spots  and 
the  posterior  fascia  much  narrower.  Other  species  oi  Pissodes 
destructive  to  conifers  in  Germany  are  P.  piniphilns,  Hbst., 
on  Scots  pine;  P.  hercyniae,  Hbst.,  on  spruce,  which  has 
been  very  destructive  in  the  Harz  and  other  forest  districts  in 
Germany  ;  and  P.  pireae,  111.,  on  the  silver-fir. 

Family  VII. — Scolytidae  (Bark-Beetles).* 
Description  of  Family. 
Beetles  small  and  cylindrical,  resembling  the  Anohiidae  in 
their  general  form.  Head  globose,  rarely  produced  into  a 
short  muzzle,  and  inserted  deeply  into  the  convex  thorax ; 
antennae  short,  more  or  less  elbowed,  and  terminated  by  a  large 
club,  their  funiculus  composed  of  2  to  7  joints.  Legs  short, 
the  til)iae  spined  or  toothed  on  their  outer  border,  the  tarsi 
with  four  evident  joints,  the  third  sometimes  bilobed.  Abdomen 
of  5  segments,  the  two  first  of  which  are  generally  fused. 

*  Eichhoff,  W.,  "Die  Europiiisclien  Borkcnkiifer,"'  Berlin,  1881.  The  best 
monograph  on  the  Bark-beetles. 


236  PROTECTION    AGAINST    INSECTS. 

Generation  :  usually  annual,  sometimes  biennial,  or  extend- 
ing over  a  year  and  a  half.  Larvae  cylindrical,  curved,  with 
tubercles  bearing  strong  hairs,  apodal,  and  closely  resembling 
the  larvae  of  weevils. 

Pupae  short  and  thick,  with  a  few  spines  and  hairs. 

The  larvae  and  beetles  live  almost  exclusively  in  the  bark, 
bast  or  wood,  more  rarely  in  the  pith,  of  our  forest  trees.  They 
attack  roots,  stems,  branches,  twigs  and  young  shoots,  and 
young  or  old  wood,  preferring  the  latter.  The  kind  of  tree 
which  they  attack,  and  the  arrangement  of  their  borings,  is 
usually  characteristic  of  each  species.  The  beetles  penetrate 
into  the  trees  by  boring  a  small  entrance-hole,  like  a  shot- 
wound,  through  the  bark.  This  is  usually  accomplished  by 
the  ?  ,  but  in  some  polygamous  species  the  3  enters  the  tree 
and  excavates  in  the  bark  a  small  pairing-chamber.  From 
this  chamber,  or  from  the  entrance-hole,  proceeds  the  gallery, 
which  is  made  by  the  ?  ,  and  in  the  outer  surface  of  which  a 
few  air-holes  may  be  perforated.  The  galleries  may  be  divided 
into  those  constructed  in  the  bark  or  alburnum,  parallel  to  the 
exterior  surface  of  the  tree,  and  those  which  run  more  or  less 
vertically  into  the  wood  ;  the  former  may  be  subdivided  into 
longitudinal  or  transverse  simple  galleries,  forked  galleries,  or 
stellate  galleries,  the  latter  being  formed  by  several  $  boring 
radially  outwards  from  the  circumference  of  a  pairing-chamber. 
The  form  of  the  gallery  is  in  the  main  constant  for  each 
species,  but  may  be  modified  by  the  size  of  the  stem  which  is 
attacked,  by  the  absence  of  knots,  etc.,  or  by  the  over- 
abundance of  insects  boring  in  the  same  trunk.  The  ?  lays 
her  eggs  as  a  rule  in  small  hollows  bitten  out  alternately  on 
each  side  of  the  gallery  she  is  gradually  excavating,  packing 
them  in  with  wood-dust.  The  larvae,  after  hatching  out,  eat 
galleries  which  radiate  from  the  breeding  gallery,  becoming 
gradually  wider  with  the  growth  of  the  larvae,  and  filled  with 
wood-powder  ;  they  pupate  in  a  chamber  formed  at  the  end  of 
the  gallery  either  in  the  bark,  bast  or  sapwood.  Finally  the 
beetles  eat  their  way  out  through  round  holes— //V/Z/^/zo/cs — 
of  the  diameter  of  their  own  bodies. 

This  is  the  general  mode  of  life  of  the  l>ark-bectles.  The 
larvae  of  those  few  species  of  Scoiytidae  w^hich  eat  wood  do  not 


BARK-BEETLES.  237 

make  regular  galleries,  but  merely  enlarge  the  egg  chambers  in 
the  wood  of  the  tree,  and  the  mature  insects  escape  through 
the  bark  by  the  original  boring  made  by  the  mother. 

Bark-beetles  are  specially  addicted  to  conifers,  and  most  of 
these  species  are  monophagous.  An  occasional  departure 
which  they  may  make  from  this  rule  is  to  be  looked  upon  as 
an  exception  due  to  local  circumstances.  There  are  also 
numerous  species  of  these  insects  which  feed  solely  on  coni- 
ferous trees  or  on  broadleaved  trees,  but  without  attaching 
themselves  exclusively  to  a  particular  kind  of  tree.  Even  the 
few  polyphagous  species  show  an  individual  preference  for 
either  coniferous  or  broadleaved  trees.  There  are  no  panto- 
phagous  bark-beetles,  which  eat  herbaceous  as  well  as  woody 
plants,  whilst  those  which  only  attack  herbaceous  plants  are 
very  few  in  number  and  without  interest  to  the  forester. 

Bark-beetles  prefer  freshly  felled  stems,  but  also  attack 
standing  trees;  they  then  commence  their  attacks  on  sickly  or 
injured  stems.  A  certain  degree  of  warmth  is  necessary  for 
them,  and  the  flight  of,  e.g.,  Tomicus  tiipograplms,  L.,  begins 
only  when  the  air  temperature  is  G8°  F.  Even  the  hardy 
B.  cliahjdtirapJius,  L.,  requires  a  temperature  of  61°  F. 

This  family  of  the  Coleoptera  is  generally  regarded  as  the 
most  important  which  the  forester  has  to  guard  against,  owing 
to  the  large  number  of  very  injurious  species  which  it  con- 
tains. Fortunately,  many  of  these  are  unknown  in  Britain, 
or  are  so  rare  as  never  to  have  been  classed  among  our 
destructive  insects. 

Judeich  and  Nitsche  distinguish  the  subfamilies  of  injurious 
bark-beetles  as  follows  : — 

Toiiiicini.  True  bark-beetles:  Head  hidden  beneath  the 
prothorax.  Anlennal  funiculus  2 — 5-jointed.  Tarsal  joints 
simple.     Apical  declivity  prominent  and  generally  toothed. 

Hijlesini.  Bast-beetles :  Head  prominent,  not  concealed 
beneath  the  prothorax.  Antennal  funiculus  5 — 7-jointed. 
Third  tarsal  joint  usually  bilobed.  Apical  declivity  without 
teeth. 

Scohjtlni.  Sap  wood-beetles  :  Head  prominent.  Antennal 
funiculus  7-jointed.  Third  tarsal  joint  bilobed.  Scarcely  any 
apparent  apical  declivity. 


238 


PKOTECTIOxV    AGAINST    INSECTS. 


A.  Subfamily  Tomicini. 

Description  of  Suhfamihj. 
Head  generally  round,  hidden  beneath  the  thorax,  and 
scarcely  visible  from  above.  Antennal  funiculus  2  to  5-jointed. 
Thorax  not  contracted  in  front,  convex  or  subspherical,  its 
surface  covered  in  front  with  small  asperate  or  tubercular 
projections,  behind  usually  punctate  or  smooth.  Tarsal  joints 
simple,  never  bilobed,  the  first  much  shorter  than  the  other 
three  together.      Elytra  sloping  downwards  at  the  apex,  the 


Fig.  99.  -Toinicus  ti/poff  rap  hits,  L. 
a  Imago,     b  Larva,     c  Pupa. 


sloping  portion,  termed  the  cqncal  dediriti/,  sometimes  im- 
pressed or  excavate  and  often  toothed.  Under-surface  of  the 
abdomen  flat.  There  are  11  genera  and  29  species  recorded 
from  Britain. 

They  generally  live  between  the  bast  and  sapwood,  some 
entirely  in  the  wood,  and  a  few  in  the  outer  bark,  and  are  very 
common  in  coniferous  forests. 


1.  Toinicus  ti/pof/raphns,  L. 
a.  Desrrijition. 
Beetle  4*5  to  o'o  mm.  long,  stoutly  built,  dark  brown  or 
blackisb,  shining,  hairy,  with  testaceous  antennae  and  legs. 
Head  with  a  small  tubercle  immediately  over  the  mandibles. 
Thorax  as  broad  as  long,  its  dorsal  surface  with  rather  fine 
sparse  punctation  over  the  posterior  half.     Elytra  with  deeply 


TOMICU.S    TYPOORAPHU.S. 


239 


impressed  striae,  somewhat  finer  posteriorly,  the  intervals  flat, 
not  punctured  except  at  the  sides  and  apex  ;  apical  excavation 
dull  and  irregularly  punctate,  with  four  teeth  on  either  side,  of 
^Yhich  the  third  is  the  largest. 


b.  Life-history. 
'  Flight-time  at  the  end  of  April  or  in  May,  at  higher  altitudes 
at  the  beginning  of  June.  Under  favourable  circumstances  a 
second  brood  may  appear  in  July  or  August.  The  beetles  are 
found  in  pairs  boring  into  the  trunks  of  large  spruce  trees 
under  the  crown,  especially  on 
the-  sunny  side ;  when  they 
reach  the  bast,  they  prepare  a 
breeding  chamber  ;  after  pairing 
the  $  excavates  one  or  more 
galleries  running  in  the  long 
axis  of  the  trunk,  which  besides 
the  original  bore-hole,  may  con- 
tain 2  to  5  air-holes.  On  the 
right  and  left  of  the  mother- 
gallery  she  bites  out  little  re- 
cesses of  the  size  of  a  poppy-seed, 
and  lays  in  each  an  egg,  generally 
to  the  number  of  30  to  50,  but 
sometimes  as  many  as  120, 
which  she  covers  with  fine 
wood-dust. 

After  14  days  the  first  larvae 
appear  in  May  and  June,  before  the  egg-laying  is  quite 
completed,  and  eat  out  slightly  winding  galleries  in  the  bast, 
somewhat  at  right  angles  to  the  direction  of  the  mother 
gallery,  pupating  at  their  ends  in  a  chamber  in  the  bast. 

The  newly  disclosed  beetles  leave  the  trees  through  round 
holes  in  the  bark  in  July  or  the  beginning  of  August,  and 
hibernate  in  stumps,  cracks  in  bark,  under  bark,  and  more 
rarely  in  "moss.  When  they  come  out  early,  before  the  end  of 
June  and  under  other  favourable  circumstances,  they  at  once 
commence  to  lay  eggs  for  a  new  brood,  from  which  beetles 
may  appear  during  September  at  the  latest. 


1 

&  '■'J 

1 

1 

f 

1 

1 

1 

' 

l"ig.  loo. — liiurowsul  I.  i;/jj'j'ji(ijj/'i>i><, 
L.,  in  spruce-bark.     {Xatural  size.) 

Commencemeiit  of  mother-galleries 
with  pairiug-chamber  (a)  and  egg- 
recesses  (A). 


240 


PROTECTION   AOAINST   INSECTS. 


The  entire  development  lasts  on  an  average  for  10  weeks, 
which  is  thus  distributed  over  the  various  stages  :  egg,  lA  to 
2  weeks  ;  larva,  2  weeks  ;  pupa,  8  weeks  ;  and  imago,  3i  to  4 
weeks.     When  circumstances  are  very  favourable  they  can 

reach  maturity  in  6  or 
8  weeks,  but  in  very 
unfavourable  circum- 
stances, damp  cold 
weather,  or  in  shady 
places,  12  to  13  weeks 
are  required. 

The  generation  is 
therefore  either  single 
or  double,  but  in  moun- 
tainous regions,  such  as 
the  Thuringian  forest 
and  the  Erzgebirge, 
a  double  generation  is 
much  rarer  than  in  the 
plains. 

In  rare  cases  where 
there  is  abundance  of 
food  and  a  very  large* 
swarm  of  beetles  a 
three-fold  generation 
has    been    observed. 

This  dangerous  pest 
has  fortunately  been 
very  rarely  observed  in 
Britain,  and  has  never 
yet  been  recorded  as  a 
destructive  insect.  Ob- 
servations on  the  dura- 
tion of  its  generation  in 
this  climate  are  tlierefore  wanting,  but  it  is  probably  an  annual 
one.    As  other  insects,  such  as  Xi/Ichonts  dispar,  Hellw.,  which 

*  Von  Kujawa  often  found  in  pieces  of  bark  10  cm.  long  and  broad,  as  many 
as  40  to  50  beetles,  and  1,000  pairs  of  beetles  attacking  one  tree  in  the  spring 
are  capable  of  producing  as  many  as  800,000  by  the  autumn. 


Fig.  101.— Burrows  of   T.  ti/pot/rajj/iii 

spruce-bark.     {Natural  size.) 

a  Paiiiug-cliamber  (with  entraute-hole) 

b  Mother-galleries  (vertical  aud  forked). 

c  Liirval-gallerics  (widening  outwards). 


TOMICUS   TYPOGRAPHUS. 


241 


are  normally  rare  in  Britain,  may  occur  unexpectedly  in  some 
numbers  and  prove  destructive,  it  is  desirable  that  the  forester 


a  Pairing-chamber. 
/)  Mother-gallery. 


c  Air-hole.         e  Flight-hole. 
(I  Larval -galleries. 


should  be  acquainted  with  the  economy  of   such  species  as 
the  present,  so  as  to  be  prepared  to  meet  a  contingent  out- 
break, which  is  by  no  means  impossible.     T.  typocjraphns,  L., 
F.p.  R 


24•^  PROTECTION    AOAINST   INSRCTS. 

may  be  imported  from  time  to  time  in  the  bark  of  unseasoned 
spruce-timber. 

Bark-beetles  are  general!}'  slow  and  lazy  insects,  which  only 
in  very  warm  weather  will  fly  to  the  top  of  trees.  A  flight  of 
them  to  remote  places  is  therefore  a  rare  occurrence,  due  to 
over  rapid  •multiplication  and  want  of  food. 

c.  Relatione  to  the  Foresl. 

The  beetle,  both  as  a  larva  and  as  a  perfect  insect,  does 
physiological  damage  to  conifers. 

It  chiefly  attacks  old  spruce  trees,  generally  those  between 
80  to  100  years  old,  and  very  seldom  when  under  50  years. 
It  is  said  to  have  been  found  quite  exceptionally  on  larch  and 
Scots  pine  and  on  the  Cembran  pine.  Even  if,  in  these 
cases,  it  has  not  been  confused  with  the  extremely  similar 
species  T.  amifinus,  Eichh.,  on  the  larch,  and  T.  cemhrae, 
Heer,  it  must  l)e  admitted  that  T.  typographm  only  appears  in 
swarms  in  spruce  woods,  and  only  attacks  trees  with  thick  bark. 

The  injuries  are  confined  to  the  bast-layer,  and  are  fatal  to 
the  trees  which  are  attacked. 

The  resulting  disease  is  called  spruce-caiiker.  Symptoms 
of  the  attack  are — yellow  or  red  discoloration  of  the  needles, 
greyness,  loosening  or  falling  ofl:'  of  the  bark,  numerous  bore- 
holes through  its  substance,  and  the  presence  on  the  trunk  of 
boring-powder  ejected  from  the  burrows. 

Trees  infested  in  the  spring  appear  differently  affected  to 
those  injured  in  the  summer.  The  needles  change  colour 
rapidly  in  the  former  case ;  in  the  latter  the  needles  remain 
green,  even  whilst  the  bark  has  already  partially  fallen 
off.  This  depends  on  the  difference  in  the  movement  and 
composition  of  the  sap  at  the  different  seasons  of  the  year. 
In  the  spring,  the  ascent  of  water  from  the  ground  is  cut  off 
from  the  crowns  of  the  trees  by  the  destruction  of  the  bast, 
and  the  foliage  at  once  begins  to  change  colour.  In  the 
summer,  the  descent  of  the  supply  of  nutritive  material 
prepared  by  the  leaves  is  cut  off,  while  the  crowns  still  get 
the  nutriment,  hence  the  needles  remain  green  while  the 
bast  is  killed.  Nevertheless  trees  attacked  in  summer 
eventually  die. 


TOMICUS    TYPOGRAPHUS.  24-3 

This  species  of  Tomicus  is  therefore  extraordinarily  destructive 
to  spruce  forests,  and  may  be  considered  the  most  destruc- 
tive of  all  European  forest  insects.  The  beetle  prefers  trees 
freshly  felled  during  the  season  of  growth  and  also  sickly 
standing  trees,  but  when  it  appears  in  large  numbers,  even 
perfectly  sound  trees  are  attacked.  It  avoids  barked  logs,  and- 
rarely  attacks  stools ;  it  utilises  only  the  upper  layers  of  fire- 
wood-stacks for  oviposition.  Its  favourite  resorts  are  thinly 
stocked  woods,  and  the  borders  of  felling-areas,  generally  in 
sheltered,  dry  warm  places  with  a  southerly  aspect.  •  Its  dis- 
tribution extends  far  north  and  high  on  the  mountains,  which 
it  prefers  to  the  plains  ;  it  is  hardy  and  but  little  affected  by 
unfavourable  weather. 

(I.  Prntertive  Rules. 

i.  Si)ruce-trees  should  be  grown  only  in  suitable  localities. 
They  should  be  mixed  with  silver-fir,  and  there  should  be  early 
and  frequent  thinnings. 

ii.  The  woods  should  be  inspected  every  May,  and  all  sickly 
trees  should  be  removed. 

iii.  All  rules  applicable  to  the  locality  for  protection  against 
windfall,  snowbreak,  etc.,  should  be  observed,  as  all  broken 
wood  affords  good  breeding  material  for  bark  beetles. 

iv.  All  broken  wood  should.be  speedily  barked  and  worked 
up,  including  semi-erect  trees  the  roots  of  which  have  been 
loosened  by  the  wind.  In  this  operation  standing  trees  should 
be  injured  as  little  as  possible. 

V.  Damage  by  game,  especially  peeling,  should  be  guarded 
against. 

vi.  Extensive  clear-cutting  areas  should  be  avoided,  and  the 
felling  areas  should  be  cleared  as  soon  as  possible.  Above  all, 
the  woods  should  be  kept  clean. 

Small  felling-areas  as  are  usual  in  the  Thuringian  forests 
should  be  adopted,  in  contra-distinction  to  the  large  felling- 
areas  in  the  Harz,  where  the  insect  has  been  notoriously 
injurious. 

vii.  All  logs  intended  to  remain  for  any  prolonged  time  in 
the  forest  should  be  barked. 

It  is  imperative  that  this  should  be  done  to  all  larger  logs, 

r2 


244  PROTECTION   AOAINST   IXSECTS. 

but  tliis  work  need  not  l)e  carried  out  till  May,  in  order  that 
the  larvae,  which  may  have  developed  in  the  logs  may  be 
destroyed.  Barking  in  May  is  also  cheaper  than  in  winter, 
as  the  work  is  easier  and  the  days  longer.  All  large  fuel  logs 
should  be  split  so  that  their  bark  may  be  limited  to  narrow 
strips.  They  should  be  stacked  ^vith  the  bark  downwards. 
Stools  remaining  in  the  ground  should  also  be  barked. 

viii.  Trap-trees  should  l)e  prepared  for  felling  (see  r,  [.). 

ix.  All  enemies  of  l)ark-beetles  should  be  preserved.  Tom- 
tits, golden-crested  wrens  and  woodpeckers  are  most  important 
in  this  respect.  "When  a  swarm  of  bark-beetles  is  approaching 
extinction,  ichneumon- wasps  appear  in  great  numbers. 

p.  Remediid  Measures. 

i.  Trap-trees  should  be  felled  from  March  till  September, 
and  should  be  barked  and  the  bark  burned  as  soon  as  the 
larvae  are  full-grown.  Old  or  somewhat  dominated  spruce- 
trees  with  small  crowns  should  be  chosen,  especially  when  the 
root-stock  has  been  somewhat  loosened  from  the  soil  by  the 
wind,  as  such  trees  are  more  readily  attacked  by  the  beetles. 
In  the  spring,  whilst  the  weather  is  still  damp,  it  is  sutlicient 
to  fell  new  trap-trees  at  intervals  of  from  5  to  0  weeks,  but  in 
summer  this  should  be  done  at  least  once  a  month.  The  local 
flight-periods  should  be  followed  in  this  respect,  and  from  8  to 
14  days  before  trap-trees  are  barked  fresh  ones  should  be  felled. 

In  order  to  facilitate  control  the  trap-trees  should  be 
numbered,  and  a  register  kept  up  to  record  the  development  of 
the  beetles.  Cogho  reckons  5  trap-trees  for  100  paces  along 
the  boundaries  of  the  felling  areas. 

Eatzeburg  recommends  that  the  trap-trees  should  not  be 
deprived  of  their  branches,  and  that  they  should  be  placed  on 
stumps  or  stones,  so  that  the  beetles  may  bore  in  from  below 
as  well  as  from  above.  Most  authors  agree  with  this  advice, 
but  Fischbach  recommends  the  lopping  off  of  the  branches,  as 
then  the  trees  dry  up  the  sooner,  and  he  also  maintains  that 
the  bark-beetles  only  attack  lopped  trees,  which  is  contrary  to 
experience.  Hess  recommends  that  the  branches  be  left,  both 
on  account  of  the  cost  of  lopping,  and  because  numbers  of 
bark-beetles   of   other   species  are  attracted   to  them.      The 


TOMICUS   TYPOORAPHUS.  24-5 

trap  trees  should  be  barked  at  latest  as  soon  as  pupation  of  the 
larvae  has  occurred,  and  all  the  bark  must  be  burned. 

If  the  barking  be  longer  deferred,  some  of  the  beetles  will 
escape,  and  if  it  be  done  too  early  too  many  trap-trees  will  be 
required,  or  the  beetles  will  oviposit  in  standing  trees. 

The  bark  must  be  carefully  removed  over  cloths,  and  this 
should  be  done  on  cool  moist  mornings,  as  the  beetles  are 
then  most  inert. 

It  is  not  sufficient  to  expose  the  bark  to  the  effects  of  the 
sun ;  this  may  kill  larvae  which  are  really  exposed,  but  in  the 
case  of  thick  bark  many  would  escape,  and  pupae  from  which 
beetles  are  just  ready  to  emerge  would  not  be  killed. 

It  is  best  to  burn  the  bark  during  cool  weather  in  natural 
hollows,  or  in  trenches,  and  to  surround  them  with  a  wall  of 
glowing  embers,  so  as  to  kill  any  beetles  which  might  happen 
to  creep  out.  The  smaller  branches  and  twigs  should  also 
be  burned,  as  they  generally  contain  many  other  smaller 
but  dangerous  bark-beetles,  such  as  T.  chalcocjrapkus,  L. 
T.  itjjHxiraphus,  L.,  may  also  swarm  in  the  branches. 

It  is  no  use  burying  the  bark  at  a  less  depth  than  IG  to 
18  in.,  as  the  beetles  can  find  their  way  out  from  shallower  pits. 

ii.  All  standing  spruce  which  shows  signs  of  having  been 
attacked  should  be  felled  and  barked  in  June,  and  the  bark 
burned. 

iii.  In  the  case  of  a  large  swarm  of  these  beetles,  all  trees 
attacked  must  be  felled,  the  larger  logs  barked  and  the 
remainder  made  into  firewood  or  charcoal.  All  recently 
attacked  trees  should  be  felled  first,  as  the  beetles  have 
probably  left  the  trees  which  have  been  long  attacked. 

Some  details  may  be  given  of  the  latest  plagues  of  bark-beetles 
in  the  Bavarian  and  Bohemian  forest  (1872-70).*  In  the 
former  about  21,500,000  c.  feet  of  wood  was  killed  in  six 
forest-ranges.  The  beetles  were  occasionally  so  numerous  as  to 
obscure  the  sun.  Accompanying  T.  ti/pographiis,  L.,  were 
T.  chalco(jrai)hus,  L.,  T.  intyograplins,  Etzb.,  T.  autofjnipJnis, 
Fab.,  Hyl.  palUatus,  Gyll,  etc.  In  the  Finsterau  range  1,000 
woodmen  were  engaged  to  fell  and  bark  the  trees,  and,  as  local 
labour  was  insufficient,  Bohemians  and  Italians  were  recruited 
for  the  work. 


246  PROTECTION   AGAINST    INSECTS. 

In  the  Bohemian  forest,  the  damage  done  was  even  on  a 
hirger  scale  :  between  1872  and  1874,  on  9,012  hectares  (22,530 
acres),  3,632,050  cm.  (127,964,000  c.  feet)  of  wood,  or  about 
450  c.  feet  per  acre,  were  felled.  Thus  altogether  in  Bohemia 
and  Bavaria  152,500,00  c.  feet  of  wood  was  killed  by  these 
insects.  The  calamity  attained  its  maximum  in  1874  and 
ended  in  1876. 

After  a  severe  windfall  in  the  Vosges  IMountains,  in  February, 
1903,  T.  tijp<>;irap]ti(ii,  L.,  attacked  the  sjiruce  woods,  especially 
in  the  Communal  forest  of  Gcrardmer,  where,  on  250  acres, 
6,216  spruce  trees  were  killed  in  1904,  and  were  immediately 
felled,  and  the  bark  with  the  larvae  burned.  In  1905,  about 
half  that  number  of  trees  were  attacked,  and  also  felled  by 
State  agency,  as  well  as  all  weakly  trees  on  the  threatened 
area.  These  latter  and  all  windfalls  were  left  lying  as  tree- 
traps,  and  were  eventually  infested  with  larvae.  They  were 
carefully  watched,  and  when  full  of  larvae  were  barked  and 
.the  bark  exposed  to  the  sun.  At  the  same  time,  larvae  of 
StaphyUnidcu'  {TloniaUiim  jj»s////m//,  Grv.),  carnivorous  beetles, 
were  found  in  the  galleries  of  the  bark  beetles  (De  Gail). 

2.   Tomicns  (i)iiiti)iiis,  Kichh. 
a.   Dpscrijiiion. 
Imago  4  to  4*5  mm.  long.     It  greatly  resembles  the  foregoing 
species,  from  which  it  can  be  distinguished  as  follows : — Head 
without  frontal  tubercle ;    interstices  be- 
tween the  elytral  striae  punctured  through- 
out ;    apical  excavation  with  a  silky  lustre, 
with  regular  rows  of  punctures. 

/>.  Lifc-hislory,  etc. 
Similar  to  the  foregoing  species,  but 
besides  spruce  the  beetle  attacks  Scots 
pine  and  larch  more  frequently  than 
T.  ii/pofirajiJtus,  L.  Its  mother-galleries 
are  bifurcating  and  frequently  stellate; 
the  larval  galleries  start  at  an  oblique 
angle    to    the   former,   and  run    in   a   zigzag  direction,  and 

*  "  Der  Borkcukiiferfia.ss  im  Hlllinicrwalik'."    Al/i/.  Fr.sf.  u.  J'jitstij.,  187J,  p.  IJID. 


/ 

-      1 

J^ 

J 

y 

r 

i\ 

Fig. 

103.- 

-Tomicus 

amitimts, 

Eichli. 

TOMICUS    AMITINUS. 


247 


248 


PROTECTION    AGAINST   INSECTS. 


both  galleries  are  more  in  the  sapwood,  whilst  those  of  T. 
lypociraphus,  L.,  are  confined  to  the  bast.  The  insect,  which 
is  more  active  than  T.  ti/pofirapJius,  L.,  is  often  commoner 
on  the  Continent.  It  is  at  present  unknown  in  Britain,  but 
is,  perhaps,  as  likely  to  occur  in  injurious  numbers  as  its 
congener,  and  is  certainly  a  worse  enemy  to  the  Scots  pine. 

r.   Proferiire.  links. 

As  in  the  former  case,  but  in  mixed  coniferous  forests, 
besides  spruce,  Scots  pine  and  larch  trap-trees  should  be 
felled. 

\ 

1 


Figs.  105  and  106. —  TomicKs  cludcographiis,  L. 


3.  Tomicus  {Pitijogenes)   chalcographns,   L.      {Small  G-tootlied 
Spruce  Bark-hccth).    . 
a.  Descrijilion. 
Beetle  2  mm.  long.     Very  shining,  almost  glabrous,  either 
entirely  bright  reddish  brown,  or  with  the  thorax  and  the  base 
of  the  elytra  dark  brown.     Prothorax  contracted  towards  the 
apex,  its  posterior  half  scantily  punctured,    with   a  smooth 
median  line.     Elytra  with  fine  punctured  striae,  their  inters- 
tices mostly  smooth  and  impunctate,  apical  excavation  narrow 
and  deeply  impressed,  its  elevated  sides  armed  with  3  teeth 
on  each  elytron,  which  are  larger  in  the  ^  than  in  the  ?  . 

//.  Lifi'-liislori/. 
Season  of  Ji'ujht :    April  and   May.      The  eggs  are   laid  in 
spruce-bark.     The  larvae  appear  in  May  and  June  ;  i)upation 
follows  in  June  and  July,  and  the  newly-hatched  beetles  bore 


TOMICUS    CHALCOORAPHUS. 


249 


their  way  out  generally  in  July.  The  insect  may  hibernate 
in  the  larval,  pupal  or  imago  stage ;  the  generation  is  usually 
annual,  sometimes  twice  in  the  year. 

T.  chalcographus  is  much  less  rare  in  Great  Britain  than 
1\  typographaa.  It  is,  however,  local  and  not  usually  common, 
resembling  in  this  respect  many  other  insects  that  feed  on  the 
spruce,  which  is  not  an  indigenous  tree.  On  the  Continent  it 
generally  accompanies  the  two  preceding  species. 

c.  Relations  lo  the  Forest. 

This  bark-beetle  ordinarily  attacks  only  the  spruce.  It  has, 
however,  occasionally  been  found  in  silver-fir,  larch  and  Scots 
pine,  and  also  on  Weymouth,  Cembran  and  mountain  pines. 


Fig.  1(17.     ,Sti.llatL'  gulkries  of 
T.  cJialcoffrapkus,  L.,  with 
egg-recesses,  ia  spruce-bark. 
(^Natural  size. ) 


Fig.  108.— Stellate  gnlkries  of  T.  rhaho.jruphm,  L 
on  spruce  sapwood,  radiating  from  the  pairing 
chambers  (rt).  h  Knots. 

{Natuval  Hize.~) 


It  is  very  fond  of  interrupted  pole-woods  about  40  years  old  ; 
in  the  case  of  old  trees  it  attacks  only  the  branches  and  crown, 
leaving  ihe  destruction  of  the  bast  of  the  stem  to  the  larger 
species.  Exceptionally  it  may  be  found  in  8  to  12-year-old 
spruce  thickets  which  have  been  attacked  by  fungi  {Aecidium 
ahictinum,  Alb.  et  Schw.). 

The  breeding-galleries  are  of  characteristic  stellate  form, 
consisting  of  4  to  7  slightly  curved  arms,  which  run  trans- 
versely rather  than  longitudinally,  groove  the  sapwood  and 
spring  from  a  pairing-chamber  excavated  in  the  outer  part  of 


250      •  PROTECTION    AGAINST   INSECTS. 

the  bark.  From  each  side  of  these  extend  the  larval  galleries 
which  ran  principally  in  the  bast,  markinj:;  the  sapwood  less 
deeply. 

The  protective  rules  are  the  same  as  for  T.  ti/ixu/rapJiiis,  L. 

4.  Tomicus  stcnofiraphus,  Daft. 
(I,  Description. 
Beetle  6  to  8  mm.  long.  The  largest  species  of  Toinieiis. 
Elongate,  cylindrical,  shining,  with  long  pubescence,  brown, 
with  yellowish-brown  antennae  and  legs.  Prothorax  longer 
than  broad,  sparsely  and  moderately  deeply  punctured  behind 
the  middle,  with  a  wide,  smooth  median  line.  Elytra  with 
strong  punctured  striae,  apical  excavation  deep,  its  elevated 
margins  furnished  with  6  teeth  on  each  elytron,  of  whicli  the 
3  upper  ones  are  small,  and  the  4th  is  the  largest. 

I).  Life-history, 

Seawn  of  fiigkt :  usually  somewhat  later  than  for  T.  fi/]>(>- 
f/rapJiKs.  It  is  found  in  May  and  again  in  August  and 
September. 

It  selects  for  oviposition  large  Scots  pines  with  thick  bark, 
and  generally  fallen  or  freshly-felled  trees,  windfalls  and  stacks 
of  firewood ;  rarely  standing  trees.  The  development  resembles 
that  of  T.  tijpof/rapliiis. 

The  larvae  are  found  in  June  and  July  ;  the  pupae  in  July 
and  August ;  the  newly  emerged  beetles  in  August  and  Sep- 
tember. The  latter  forthwith  pair,  and  a  new  brood  com- 
mences. The  insect  hibernates  under  bark  as  an  imago  of 
the  first  or  second  brood. 

Generation  either  annual  or  twice  in  the  year. 

r.  Jlchiliona  to  the  Forest. 

The  beetle  attacks  the  Scots  pine,  and  prefers  old  trees 
with  thick  bark.  It  has  also  been  observed  on  black  and 
cluster  pines,  and  very  rarely  on  spruce.  In  the  absence  of 
old  woods  it  has  here  and  there  attacked  poles  20  to  30  years 
old.  The  attack  is  on  the  bast,  and  resembles  that  of  T.  typo- 
ijrapttus,  but  is  less  regular,  and  the  breeding  galleries  are  long 


TOMICUS   LARICIS. 


251 


and  wide.  Sometimes  the  numerous  larval  galleries  coalesce, 
in  which  case  the  brood  live  together  and  completely  under- 
mine the  bark.  This  beetle  is  more  frequent  in  the  plains 
than  in  the  mountains,  and  may  be  considered  rare.  In 
Britain  it  has  been  found  about  as  often  as  T.  typociraphus,!^. 
The  protective  measures  are  the  same  as  for  that  insect. 


Fig.  lO'J. — T.  stcitogyapJiHs,  Duft. 


Fig.  110.— r.  hirlcis,  Fal.r. 


5.  Toiiiiciis  laricis,  Fabr. 
(/.  Descriplion. 
Beetle  3"5  to  4  mm.  long,  of  cylindrical  shape,  dark  In-own, 
shining,  thinly  haired,  with  antennae  and  legs  ferruginous. 
Thorax  scarcely  longer  than  broad,  its  posterior  half  sparsely 
punctured,  with  a  less  distinct  median  impunctate  line.  Elytra 
with  regular  punctured  striae,  the  interstices  with  single  rows 
of  fine  points,  apical  excavation  almost  circular,  deep,  its 
elevated  margin  with  from  3  to  6  short  blunt  teeth,  and  an 
accessory  tooth  on  the  inner  side  of  the  2nd  and  3rd  teeth. 


b.  Life-hislory. 

Season  for  ji'Kjht :  April  and  May  ;  a  second  brood  appears 
in  July  and  August. 

The  eggs  are  laid  in  the  bark  of  various  conifers.  Stems 
injured  by  a  forest  fire,  or  Celled  trees,  are  selected  in  preference 
for  egg-laying. 

Larvae  appear  in  June,  and  those  of  the  second  brood  in 
August  or  September.  Pupation  takes  place  in  the  bast  in 
June,  July,  and  again  in  September  and  October. 


252 


PROTKCTIOX    AfiAINST    INSKCTS. 


The  first  brood  reaches- maturity  in  July,  and  the  second 
brood  in  October.     The  beetles  hibernate  under  the  bark. 

The  generation  is  therefore  double,  and  may  be  threefold  in 
Southern  France.  The  beetle  is  found  almost  throughout 
Europe,   and   is  common  in  most  places.     In  Britain  it  is, 

perhaps,  the  least  rare  species 
of  the  genus,  if  Toiuiciis  bidcii- 
tatiis,  llbst.,  be  excepted. 

,^,j,,__^__,^^__,,  ''•    f^f'l"li"fi-^  lo  the   Forest. 

W'     €^  '^^m^mil  '^^■'^  beetle  does  not  by  pre- 

'"*'  ^  >^^^^KSi''''^'l'll  ference  attack  the  larch,  but 
is  found  on  all  conifers,  par- 
ticularly on  the  Scots  pine, 
and  then  on  the  spruce,  rarely 
on  larch  or  silver-fir.  It  attacks 
poles  and  mature  trees,  and 
exceptionally  young  growth. 

The  mother  -  galleries  and 
larval  chambers  are  in  the  bast. 
The  former  are  generally  ver- 
tical, slightly  curved  or  bent  at 
an  angle  at  either  end,  with 
2  to  4  air-holes  (Fig.  105)  ;  the 
larvae  eat  together  in  regular 
family  chambers,  so  that  special 
larval  -  galleries  do  not  exist 
(Fig.  105,  a). 
The  beetle  is  said  to  gnaw  young  plants  (Scots  pine),  near 
the  collum,  but  this  statement  requires  confirmation. 


Fig.  111.— litirn.w.  m  T.  !„,„,., 
Fabr.,  in  Scots  piue  baik.  {yalural 
size.) 

a  Mother  gallery  with  eggs  (e) . 
b  Larvae  feeding  in  family  chamber. . 


(I.  Protcrtire  /t'l'tfs. 

(a)  Prevention.  • 

Keeping  the  forest  clean,  and  rapid  clearing  of  felling-areas. 

(b)  Remedial  Measures. 

i.  Trap-trees  as  for  T.  typofiraphua,  L. 

ii.  Poles  or  logs  used  for  traps  stuck  and  placed  into  the 


TOMICUS    BIDENTATUS.  258 

ground  in  March.     These  should  be  examined  in  June,  and 
those  containing  larvae  should  be  burned. 

iii.  All  young  plants  which  may  be  attacked  and  which  may 
be  recognised  by  the  reddening  of  the  needles,  should  be  pulled 
up  in  June  and  burned. 


6.   Toiiticiiti   {Pit>/()[i<'iies)   Jiidentatiis,  Herbst. 
a.  Dfi-'irriplio)). 
Beetle  2  to  3  mm.  long;  pitchy-black,  somewhat  shining, 
with  fine  hairs  :  antennae  and  legs  ferruginous.     Thorax  con- 


\ 

I-'if^s.  112  anil  113. —  Tumiciis  hidoilatiis,  Hbst. 

stricted  in  front,  and  rather  deeply  punctate  behind,  with  a 
smooth  median  elevated  line.  Elytra  with  rows  of  punctures, 
impressed  towards  the  sides  only,  apical  excavation  somewhat 
deep  in  the  3  ,  with  a  single  strong  hooked  tooth  on  each 
side ;  in  the  ?  the  declivity  is  impressed  on  either  side  of  the 
suture,  and  the  teeth  are  reduced  to  inconspicuous  tubercles. 

b.  Life-history. 
The  ?  lays  her  eggs  in  May  and  June  in  Scots  pine  woods, 
on  young  plants,  poles,  branches,  and  on  refuse  on  felling 
areas.  The  pairing  chamber  is  often  furnished  with  short 
prolongations  which  are  breeding  galleries  commenced  but 
abandoned,  and  penetrates  deeply  into  the  sapwood.  Portions 
of  the  stems  covered  by  thick  bark  are  avoided. 


254 


PROTECTION    AGAINST    INSECTS. 


The  larrae  appear  in  June  and  July  ;  the  second  brood  in 
August  and  September. 

Pupation  :  in  July  and  August,  in  the  bast  or  sapwood  ;  the 
second  brood,  which  hibernate  as  larvae, 
pupate  in  the  following  May. 

FWiht -period  :  in  August.  The  second 
brood  is  mature  by  June  of  the  following 
year,  and  is  followed  by  a  third  brood  in 
the  autumn  which  winter  in  the  beetle 
stage. 

The  generation  thus  extends  over 
1^  years.  The  beetle  frequently  appears 
in  company  with  T.  laricis,  Fabr.,  and 
is  widely  distributed.  It  is  common  in 
conifer  forests  in  Britain. 

c.  Rchiiions  lo  the  Forest. 
The  common  Scots  pine  is  the  chief 
tree  attacked  by  this  bark-beetle.  It 
has,  however,  been  also  found  in  the 
Weymouth,  cluster  and  mountain  pines, 
and  K.  H^rtig  has  noticed  it  on  the 
spruce.  It  prefers  the  plants  of  6  to 
1'2- year -old  cultivations,  and  only 
attacks  the  branches  and  twigs  of  older 
trees,  where  the  bark  is  thin.  As,  how- 
ever, it  attacks  branches  which  are 
thoroughly  sound,  the  crowns  of  trees 
are  considerably  thinned  out  b}'  this 
beetle,  especially  when  other  l)ark- 
beetles  and  longicorn  beetles  join  in 
the  attack. 

The  bast  and  sapwood  are  both 
attacked.  The  irregularly  stellate 
mother  -  galleries  are  generally  4  to 
7-armed,  rarely  3-armed.  The  branches  of  these  galleries 
run  longitudinally  rather  than  horizontally,  and  have  a 
knotted  appearance,  as  the  egg  chambers  are  large  and 
comparatively  far  apart.     The  larval  galleries  are  somewhat 


Fig.  114.— Burrows  of  T. 
bidcnttttus,     nb.st.,      on 
pine  .sapwood.    [Xatiiral 
size.) 
a  Pairinfj-chambers. 


TOMICU.S    LINEATU.S.  255 

winding  and  sparsely  distributed;  both  kinds  of  galleries  may 
be  clearly  seen  on  the  sapwood,  though  those  made  by  the 
larvae  are  more  marked  in  the  bast. 

This  beetle  readily  attacks  woods  which  have  suffered 
from  fire.  Trees  which  have  been  severely  attacked  may  be 
recognised  by  the  yellowish  colour  of  their  crowns. 

(1.  Proteclive  UiiU^. 
As  for  T.  laricis,  L. ;  but  trap-trees  are  useless.  Instead 
of  these,  branches  may  be  used  as  traps,  which  should  be 
burned  as  soon  as  they  are  stocked  with  larvae,  and  replaced 
by  fresh  ones  every  4  to  5  weeks  until  the  autumn.  Poles 
seen  to  be  attacked  by  larvae  should  be  immediately  felled  and 
barked,  and  the  bark  burned. 

7.  Tomicns  acuminatus,  Gyll. 
Beetle  3  to  4  mm.  long  ;  brown,  with  yellow-grey  pubescence. 
Elytra  regularly  punctate-striate,  the  excavation  circular, 
acuminate  at  the  apex  of  the  suture,  its  elevated  margin  with 
3  teeth  on  either  side,  the  first  a  small  tul)ercle,  the  last  the 
largest,  and  situate  about  the  middle  of  the  margin. 

Life-Iiistori/,  cic. 

This  species  chiefly  infests  the  crown  of  full-grown  or  old 
Scots  pines.  The  mother-galleries  consist  of  3  to  5  branches, 
radiating  from  a  spacious  pairing-chamber  and  grooving  the 
sapwood  rather  deeply  when  excavated  in  thin  bark.  The 
larval  galleries  are  twisted,  frequently  coming  into  contact  or 
even  crossing,  l)ut  as  a  rule  scarcely  marking  the  sapwood. 

The  species,  though  not  very  common  in  Europe,  is  not 
rare  in  Scotland  and  the  north  of  England,  and  must  be  con- 
sidered as  one  of  our  injurious  species.  Its  attacks  must  be 
treated  on  the  same  lines  as  those  of  other  species  of  Tomicus. 

8.   Tomicus  lineatus,  Oliv. 
a.  Descriijlion. 
Beetle  3  to  4  mm.  long,  short  and  cylindrical,  black,  the 
hinder  part  of  the  thorax  and  the  elytra  yellowish  brown. 


256 


PROTKCTION   AGAINST   INSECTS. 


The  latter  witli  tliree  black  bands  each,  aloiif;  the  suture,  in 
the  middle  and  along  the  outer  margin,  of  which  the  middle 
band  is  not  alwaj's  complete  ;  they  are  marked  with  rows  of 
large  punctures ;  apical  declivity  not  impressed  nor  toothed. 
Antennal  club  flattened  oval,  blunt  at  apex,  without  trace  of 
sutures. 


h.  Life-hislory. 
The  season  for  iliglit  is  in  March  and  April,  and  again  in 
June  and  July. 

The  ?  prefers  felled  trees,  provided  they  are  still  sufficiently 
moist,  also  windfalls,  and  sometimes  stems  still  in  the  ground, 
high  stumps  or  broken  trunks.     A  good 
deal  of  care  is  shown  in  the  selection  of 
"^  ^^HB|L  ;^         breeding  places,  and  the  material  must 
^^■P^rm!f  },Q  neither  too  fresh  nor  too  dry.      The 

beetle  rarely  bores  into  cleanly  barked 
1  stems,  and  is  only  rarely  found  in  stand- 
ing healthy  trees.  The  ?  bores  verti- 
cally into  the  tree  for  an  inch  or  more, 
constructing  one  or  more  brood  galleries 
at  the  end  of  her  tunnel,  usually  at 
right-angles  to  the  entrance  burrow, 
and  always  transversely  to  the  long  axis  ; 
in  the  floor  and  roof  of  these  galleries 
she  gnaws  small  cylindrical  holes  vertically  into  the  wood  for 
the  reception  of  the  eggs,  and  after  oviposition,  she  blocks 
tliese  holes  with  wood-dust,  forming  partitions  between  the 
secondary  and  primary  galleries.  There  are  generally  from 
30  to  50  eggs. 

The  larvae  appear  in  May,  and  those  of  the  second  brood  in 
July  and  August.  They  pupate  in  a  cocoon  of  particles  of 
wood  in  July,  and  again  in  August  and  September. 

The  imagos  appear  about  the  middle  of  July,  and  leave 
their  birthplace  through  the  old  mother-gallery,  after  Ijreak- 
ing  through  the  partition,  which  remains  intact  up  to  that 
time.  They  at  once  set  to  work  to  produce  a  fresh  brood. 
The  species  is  widely  distributed  throughout  Europe,  but  is 
confined  in  Great  Britain  to  a  few  localities  in  the  Tay  and 


Wn.—T.  linealits, 
Oliv. 


TOMTCUS    LINEATUS. 


257 


Dee  districts  of  Scotland,  where  it   has   not   as   yet   proved 
injurious. 

c.  Re]((lions  to  the  Fonsf. 
The  beetle  attacks  all  conifers,  but  chiefly  the  silver-fir  and 
spruce,  and  only  large  trees.     The  round-bored  gallery  pene- 
trates at  right  angles  to  the  axis  of  the  tree.     It  consists  of 


Fig.  116. — Transverse  sec- 
tion of  a  spruce-stem  {re- 
duced) with  burrows  of 
T.  lineatus,  Oliv.  (Natural 
size.) 

a  Entrance-galleries. 

b  Breeding-galleries. 


Fig.  117. — Eadial  burrows  of 
T.  Ihieatvs,  Oliv.,  in  spruce- 
wood.     [Natural  size.) 

a  Mother  galleries. 

b  Larval  galleries  and  pupal 
chambers. 


an  entrance  passage  and  breeding-gallery.  The  latter  is  either 
merely  a  prolongation  of  the  former,  or  is  usually  composed 
of  two  branches,  which  generally  follow  the  annual  zone  of 
the  wood  in  the  same  plane.  It  is  rare  that  several  annual 
zones  are  traversed  by  it.  The  entrance  gallery  is  generally 
confined  to  the  sapwood.  The  larvae  on  emergence  feed  on 
the  sap  of  the  wood,  and  by  gnawing  extend  their  egg 
chambers  to  short  cylindrical  tunnels  in  which  they  pupate. 


258  rnOTKCTION    ACAINST  IXSKCTs. 

In  the  secondary  galleries,  and  on  the  partitions,  white  fungous 
mycelia  {Monilia  Candida)  appear,  which  are  also  devoured, 
not,  as  was  formerly  supposed,  because  they  are  the  chief  food 
of  the  larvae,  but  to  clear  the  way  for  the  larvae. 

Later  on,  the  walls  of  the  galleries  and  the  adjoining  wood 
become  black  owing  to  fungoid  growth. 

The  beetles  damage  the  commercial  value  of  the  wood,  the 
finest  stems  being  frequently  bored  like  a  sieve,  and  rendered 
useless  for  most  purposes.  The  insect  is  most  frequently 
found  in  forests  where  much  wood  is  broken  by  wind  or  snow, 
and  where  there  are  winter-fellings. 

(L  Protective  Rulefi. 

i.  Immediate  removal  of  all  sickly  coniferous  trees  and 
of  broken  wood  and  stumps  from  the  forest.  The  latter 
should  at  least  be  barked,  if  their  timely  removal  is  not 
advisable. 

ii.  Felling  in  the  growing  season,  and  immediate  removal 
of  the  bark. 

It  may  happen,  when  the  beetle  is  in  great  numbers,  that 
barked  trees  may  be  attacked.  If  winter-felling  cannot  be 
avoided,  and  barking  is  impossible,  the  wood  should  be 
removed  before  March. 

f.  Remedial  Pleasures. 

i.  Tree-traps  may  be  felled  in  July  and  August  to  attract 
the  beetles  about  to  lay.  These  trees  must  be  barked  and  split 
open  to  destroy  the  larvae,  and  fresh  tree-traps  provided 
continually  till  October. 

ii.  Firewood  may  be  used  as  traps,  but  must  be  removed 
from  the  forest  before  the  beetles  come  out. 


9.   Tomicus  domrsticus,  L. 

a.  Doscriplioii. 

Beetle  3  to  4  mm.  long.     Similar  to  the  preceding  species 

but  more  elongate,  with  the  prothorax  entirely  black  ;  the 

elytra  livid  yellow,  regularly  punctate-striate,  and  impressed 


nniK'US    DLSPAR. 


250 


at  the  apex  on  either  side  of  the  suture.  Antennal  chih  as  in 
the  preceding  species,  but  produced  into  a  bhmt  angle  on  the 
inner  side  of  the  apex. 


h.   Lifc-liisiorij,  etc. 

SimiLar  to  that  of  T.  Uncatus  ;  but  less  important  on  account 
of  its  breeding  chiefly  in  stumps  and  windfalls.     It  attacks  not 
conifers  hut  broadleaved  trees, 
chiefly  beech,  oak  and  l)irch, 
also  lime. 

The  mother-galleries  do  not 
branch  as  a  rule,  but  run  verti- 
cally into  the  wood  for  two  or 
more  inches.  This  insect  is 
not  uncommon  in  large  wood- 
lands in  Britain.  If  it  injures 
commercially  valuable  timl)er, 
the  forest  should  be  cleared 
of  material  containing  the 
insects ;  spring  felling  is 
desirable. 

T.  qucnus,  Eichh.,  is  still 
more  like  T.  lineatm,  Oliv.,  in  appearance,  but  is  distinguished 
by  having  the  antennal  club  angulate  at  the  apex,  as  in 
T.  domesticus.  In  habits  it  resembles  the  latter  species,  but 
is  much  less  common  in  Britain,  being  almost  entirely  confined 
to  the  neighbourhood  of  Sherwood  Forest. 


118.— Radii 
ticus,  L. 


1  galleries  of  T.  domes- 
in  beech-wood. 


[Natio-al  size.) 


10.  Tomiciis  dispar,  Fabr. 
n.  Description. 
Beetle  S  2  mm. —  ?  3  mm.  long.  Pitch-black,  the  antennae 
and  legs  testaceous-red.  S  short,  convex,  ovoid  and  very 
hairy,  with  the  thorax  granular  in  front,  punctured  towards 
the  base,  with  a  smooth  median  line.  The  $  cylindrical,  its 
thorax  in  front  strongly  asperate.  Elytra  strongly  arched  at 
the  declivity,  with  rows  of  deep  punctures,  and  raised 
tuberculate  interstices  between  them. 

s2 


260 


PHO'rKt:TION    ACAINST    INSECTS. 


//.  Lifi'-liisUinj. 

The  srasou  for  jUght  is  in  May.  Tlie  $  bores  into  several 
kinds  of  broadleaved  trees  to  lay  her  e^rgs,  in  preference 
below  a  branch,  but  never  near  tlie  ground,  attacking  felled 
wood  and  young  standing  trees. 

The  larvae  a])pear  in  June,  pupate  in  July  in  the  secondary 
galleries,  and  the  beetles  emerge  in  August.  They  hibernate 
in  the  galleries,  and  there  is  only  one  generation.  This  beetle 
not  everywhere  common  on  the  Continent,  and  till  recently  was 
regarded  as  one  of  the  rarest  British  insects.  But  since  1891 
it  has  been  destructive  in  certain  Gloucestershire  fruit-orchards. 


Figs.  119  and  120.-7'.  dispar,  Fa])r. 


r.  JxeJafions  to  the   Forest. 

Oak  and  fruit-trees,  especially  apple  and  pear,  are  chiefly 
attacked ;  also  beech,  hornbeam,  birch,  maple,  ash,  alder, 
horse  chestnut  and  plane. 

The  ?  bores  a  vertical  entrance-gallery  into  the  tree,  like 
other  species  which  enter  the  wood  deeply,  from  which  she 
excavates  one  or  more  transverse  secondary  galleries  along  the 
line  of  one  of  the  annual  rings  ;  from  these  again  are  con- 
structed tertiary  brood-galleries  which  run  longitudinally 
upwards  or  downwards.  In  the  brood-galleries  the  eggs  are 
laid  in  clumps ;  the  larvae  live  in  them,  and  do  not  bore  but 
feed  on  the  exudations  of  sap  and  on  the  fungi  which  overgrow 
the  burrows.  The  galleries  are  bored  at  the  height  of  the 
growing  season  in  the  outer  zones  of  the  wood  of  perfectly 


TOMICUS   BISPAR. 


261 


''^T^'^yjT^u 


healthy   saplings,    which    become    diseased    and    die.      The 
presence  of  the  beetles  may  be  detected  by 
the  l)orings,  and  the  whitish  bore-dust  heaped 
up  at  the  foot  of  the  plant. 

The  beetle  is  very  destructive  in  orchards, 
and  sometimes  to  young  oak- saplings. 

(/.  Protective  Rides. 
Unbarked   orchard-props   should   not  be 
used,   as   it    frequently   happens    that   the 
beetle  finds  its  way  from  such  props  into 
the  fruit-trees. 


p.  Remedied  Jleasiire/i. 

i.  The  entrance-holes  to  the  burrows 
should  be  smeared  with  tar. 

ii.  All  plants  which  have  been  attacked 
should  be  removed  and  burned. 

iii.  The  beetles  may  be  killed  inside  the 
galleries  with  wire,  and  the  bores  blocked  up 
by  wooden  pegs.  This  method  of  treatment 
is  generally  impracticable,  but  has  been 
adopted  with  success  in  orchards. 


B.  Subfamily  Hylesinini. 
Description  of  Snhfainilij. 

Head  prominent  and  not  concealed  by  the 
prothorax,  with  a  short  and  broad  rostrum  ; 
antennae  with  a  funiculus  of  5  to  7  joints ; 
thorax  narrowed  in  front,  uniformly  punc- 
tate on  the  back;  first  tarsal  joint  much 
shorter  than  the  other  three  together,  the 
third  bilobed  or  heart-shaped  (except  in  the 
case  of  Pohj(jrai)hus  imhescens,  Er.);  apical 
declivity  convex  and  without  teeth ;  under- 
surface  of  the  abdomen  not  abruptly  flexed  upwards. 

Most   species   breed   in   the   bast   and   especially  frequent 
conifers ;  a  few  make  pupal  chambers  in  the  sap-wood. 


Fig.    121. — BiuTows 

of  T.  dispar,  Ftibr., 

in   an  oak-sapling. 

{Xatural  size.) 
a  Entrance     -    hole, 

usually     under     a 

twig. 
b  Mother-galleriesj. 
(■  Commencement    of 

lateral  galleries. 
(I  Completed     lateral 

galleries   in   which 

tlie  larvae  lie. 


262 


PKOTECTION   AGAINST    INSECTS. 


1.  Jli/htstrs  jKiUiafus,  Gyll. 
(I.   Iksriijilio)}. 

Beetle  3  to  4  mm.  long,  of  stout  build  ;  thorax  and  elytra 
reddish-brown  and  covered  with  fine  grey  hairs ;  the  former 
broader  than  long,  strongly  constricted  in  front,  densely  and 
coarsely  punctured  with  a  narrow  median  ridge.  Elytra  with 
rather  line  punctured  striae,  the  interstices  rugose,  tuberculate, 
and  with  a  series  of  short  hairs. 


/'.  Jyife-histonj. 
The  flight-season  is  at  the  end  of  March  and  April. 
Coniferous  wood  in  logs,  or  stacks  of  fuel,  chiefly  when 
damp  and   lying  in  shady  places,   are 
selected  to  receive  the  eggs. 

The  newly  disclosed  beetles  appear 
from  April  or  May  until  July ;  they  at 
once  pair  and  produce  a  new  brood,  and 
in  July  new  breeding  galleries  are  found 
amongst  the  larvae  and  pupae  of  the 
old  brood. 

The  second  brood  of  beetles  appears 
from  the  beginning  of  October,  and 
hibernates  in  cracks  of  the  bark, 
moss,  etc.  There  are  two  generations, 
and  the  species  is  common  and  widely 
distributed  both  in  Britain  and  on  the  Continent. 


Fig.  122.— Mplanh's 
paUiaiKs,  Gyll. 


c.  Rclaiionx  to  the  Fon-nt,  etc. 

The  l>eetle  attacks  all  conifers,  but  chielly  spruce,  and 
secondly  Scots  pine,  silver-fir  and  larch  exceptionally ;  only 
middle-aged  and  old  wood;  they  also,  both  as  larvae  and  beetles, 
damage  the  bark  and  bast. 

The  primary  galleries  are  short  and  hooked,  like  intestines. 
They  are  sometimes  forked.  The  secondary  galleries  are 
conspicuously  long  and  irregular,  often  crossing  one  another 
and  extending  down  to  the  sap-wood. 

Authorities  differ  as  to  the  destructiveness  of  this  beetle — 
liatzeburg,  Konig  and  Kellner  consider  it  very  destructive  ; 


HYLASTES   ATER. 


263 


Stein  thinks  its  destructiveness  over-rated,  and  Eichhoff  that 
it  only  does  secondary  damage. 

More  information  as  to  its  habits  is  therefore  called  for. 
The  economic  treatment  of  this  species  is  the  same  as  that  of 

T.  ti/p(Kj!-apJ(ll>>,  L. 


Figs.  123  ami  124. — Ikinows  oi  H.  paUialus,  Gyll.,  in  spruce  bark. 

{Natural  size.) 

a,  $  Characteristic  mother-galleries.  y  Larval  galleries. 

5  Mother-galleries  wiiere  no  larvae  have  been  produced. 


2.  Hylastcs  ater,  Payk. 
a.  Description. 
Beetle  4  to  5  mm.  long,  of  slender  build  ;  deep  black, 
brownish -red  antennae  and  tarsi.     Thorax  much  longer 


with 
than 


264  PROTECTION   AGAINST    INSECTS. 

broad,  parallel-sided,  closely  and  deeply  punctured,  with  a 
smooth  median  ridge.  Elytra  deeply  punctate-striate,  with 
wrinkled  and  somewhat  tuberculate  interstices. 

h.  Life-liistory. 

This  species  and  //.  opacus,  Er.,  have  a  similar  biological 
history,  which  is  as  follows : — They  fly  in  March,  April  and 
May.  Eggs  are  laid  in  stumps  and  roots  of  the  Scots  pine, 
in  preference  in  those  of  trees  felled  in  the  previous  year ;  but 
in  the  case  of  //.  ater,  eggs  are  sometimes  laid  in  young  pine 
transplants. 

The  larvae  appear  in  April,  and  the  mother  and  larval 
galleries  then  form  a  confused  pattern. 

The  newly  hatched  beetles  may  first  be  seen  in  June,  and 
according  to  Eichhoff  they  may  produce  a  fresh  brood,  which 
comes  out  in  October  or  November.  The  imagos  hibernate  in 
stumps  or  in  plants  which  they  have  injured. 

The  generation  is  annual  or  double,  or  it  may  be  biennial 
according  to  various  observers  ;  it  requires  further  elucidation. 

c.  ReJations  to  the  Forest. 
This  Ijeetle  is  only  hurtful  in  the  imago  stage  ;  before  the 
middle  of  June  they  begin  to  wander  from  their  breeding 
places  to  the  neighbouring  plantations  and  eat  the  bark  of 
2-  to  6-year-old  Scots  and  Austrian  pine,  and  of  other  species 
of  pine,  especially  at  the  collum  and  on  the  roots.  The 
needles  of  the  plants  which  have  been  attacked  turn  yellow 
and  fall  off ;  the  plants  die,  or  become  so  loose  in  the  soil  that 
they  can  be  easily  pulled  up.  //.  ater  is  common  in  Britain, 
and  its  ally  //.  opacus,  Er.,  is  nearly  as  frequent.  The  latter 
species  is  also  recorded  from  elm  and  ash. 

(/.  Protective  Rules. 

i.  Timely  and  thorough  removal  of  stumps  and  roots, 
burning  of  the  bark,  or  thickly  smearing  all  exposed  wood 
with  tar. 

ii.  Thorougli  cleaning  of  the  felling  area. 

iii.  Careful  planting,  and  avoidance  of  all  deep  planting. 


PINE-BEETLE. 


265 


e.  Remedial  Measures. 

i.  Burying  trap-logs,  or  laying  out  bark-traps  as  against 
Hylohius  ahietis,  Fabr.,  page  225. 

ii.  Digging  up  all  attacked  plants  with  a  spade,  and  burning 
them  in  kilns  with  the  roots  inwards. 


3.  My  do  pi  dins  piiiipcnla,  L.   (I'inc-hcetle). 
a.  Description. 
Beetle  4  to  5  mm.   long;  head  and  thorax  black,  elytra 
blackish  or  dark  brown ;  antennae  and  tarsi  rusty  red.    Thorax 


125.  — Mijelophilus piniperda,  L. 
Imago,     b  Larva,     c  Pupa. 


not  longer  than  its  width  at  the  base  and  tapering  in  front, 
shining,  with  scattered  deep  punctures,  obsolete  towards  the 
middle.  Elytra  with  fine  punctured  striae  ;  the  interstices 
somewhat  granulate,  each  with  a  row  of  bristle-bearing 
tubercles,  absent  on  the  apical  portion  of  the  second  interstice 
(counting  from  the  suture),  vhich  is  slightly  impressed. 


b.  Lifc-hi.<lonj. 
Thejliyht  is  at  the  end  of  March,  April,  and  also  in  May  ; 
under  favourable  circumstances,  again  in  June  and  July.  The 
eggs,  to  the  number  of  100  and  over,  are  laid  similarly  to 
those  of  T.  typoyraphus,  L.,  on  large  Scots  pines,  etc.,  and  in 
preference  on    the   south-west   side   of  the  trees.     There  is. 


266  PROTECTION    AOAINST    INSECTS. 

however,  no  breeding  chamber,  as  copulation  takes  place  out- 
side on  the  trees.  The  2  prefers  dying  or  felled  timber  with 
rough  bark,  windfalls,  stumps  and  broken  trees.  On  standing 
trees  the  lower  coarse-barked  portion  of  the  stem  is  selected, 
as  the  brood-galleries  are  entirely  limited  to  the  bark.  If  no 
old  wood  is  to  be  found,  the  beetle  attacks  young  poles. 

The  larvae  hatch  in  April  or  May,  in  about  12  to  20  days 
after  the  eggs  have  been  laid  ;  they  pupate  in  June  or  the 
beginning  of  Jul3^ 

The  beetles  appear  at  the  end  of  June  and  in  July.  Some 
later  ones  may  emerge  in  August.  The  beetles  which  develop 
early,  in  June  in  mild  localities,  produce  a  second  brood,  which 
is  ready  by  the  end  of  August,  and  attacks  the  terminal  shoots 
of  the  tree  and  branches  ;  those  which  come  out  later  do  not 
pair  but  at  once  commence  their  destructive  work  in  the 
crowns  of  the  trees.  Thus  the  whole  development  of  the 
beetle  may  last  from  60  days  under  very  favourable  circum- 
stances, to  80  days.  In  order  to  hibernate,  the  beetle  bores 
into  the  rootstock  or  roots  of  standing  trees,  sometimes  into 
stumps,  often  into  the  thick  bark  at  the  lower  part  of  the 
trunk. 

The  generation  is  either  single  or  double.  The  insect  is  very 
numerous,  and  widely  distributed  ;  it  is  common  in  almost 
every  pinewood  throughout  Britain. 

r.  Rcl((ii()ns  io  lite  Fores/. 

The  beetle  generally  attacks  the  Scots  pine,  but  also  the 
Weymouth  and  cluster  pines  and  other  species  of  pines.  It 
has  also  been  frequently  observed  on  the  spruce ;  rarely  on 
larch. 

It  attacks  old  and  young  trees,  but  prefers  the  former,  and 
is  very  rarely  found  in  woods  less  than  ten  years  old.  Woods 
between  thirty-five  and  forty  years  old  are  chiefly  attacked. 
The  insect  does  three  kinds  of  damage. 

First  of  all  the  beetles  and  larvae  attack  the  bark  and  bast. 
The  beetle  makes  longitudinal  galleries,  with  one  to  three  air- 
holes, which  may  be  straight,  but  generally  commence  with  a 
characteristic  hook-like   bend.     The  entrance-hole  is  usually 


PINE-BEETLE. 


267 


out 
gal- 
the 


under  a  bark- 
scale,  and  may 
be  marked  by 
ejected  wood  - 
powder  or  by  a 
drop  of  tur- 
pentine. Tbe 
larvae  eat 
secondary 
leries  in 
bast,  which 
branch  out  at 
right  angles  to 
the  primary  gal- 
lery, soon  be- 
coming wide, 
irregular  and 
confluent.  They 
only  graze  the 
sapwood.  The 
pupae  and  im- 
mature beetles 
are  embedded  in 
the  bark,  near 
its  outer  surface. 
The  second 
and  most  serious 
form  of  damage 
is  done  to  the 
young  shoots. 
The  newly-dis- 
closed beetles 
of  the  first  or 
second  broods, 
in  August  and 
September,  bore 
into  the  pith  of 
young  pine  - 
shoots      at     a 


126. — Burrows  of  M. pinipeida,  L.,  iu  piue-bark. 
{Xaiural  size.) 


a  Characteristic  angle  near  tlie  beginning 

gallery. 
b  Larval  gallery  free  of  wood-dust. 
c  Larval  gallery  full  of  wood-dust. 
(I  Air-pa.'<r<ages. 


if  the  mother- 


268 


PRoriocrioN  acain.st  insects. 


distance    of    1    to    t]   in. 


- 

^ 

'^f  :, 

^       1- 

/ 

,/'■  :'^-: 

^  « 

0 

^:' 

Fig.  127.— Piue-bark  with  cham- 
bers («),  pupae  (b)  and  imagos  (e) 
J/,  pimpcrda,  L. 
[Xatural  size.) 


Fig.  128.— I'ine-shoot,  hdllowed 
out  by  J/,  jjiiiipcri/d,  L.,  witli 
two  beetle-holes. 

pine  forests.     Fig.  128   si 
a  cone.     Such   twigs  may 


from  their  extremities,  choosing 
especially  those  of  sickly  or  old 
trees,  in  preference  on  sumiy 
borders  of  woods ;  they  eat  out 
a  burrow  about  an  inch  long, 
working  upwards  to  the  buds. 
The  entrance  -  holes  into  these 
nhoots  are  surrounded  by  a 
whitish  ring  of  resin.  The  beetle 
leaves  the  hollowed  -  out  shoot 
either  by  the  original  bore-hole 
or  by  a  fresh  hole  made  at  the 
end  of  the  burrow,  and  recom- 
mences his  destructive  work  in 
another  shoot.  In  these  galleries 
excrement  is  never  found,  and 
thus  the  action  of  M.piiiipcrda,  L., 
may  be  distinguished  from  that 
of  Tortrix  huoliana,  Schifif.,  the 
caterpillar  of  which  also  bores  out 
Scots  pine  shoots,  but  always 
leaves  excrement  in  the  borings. 
Weak  side-shoots  which  have  been 
bored  break  off  generally  at  the 
bore-hole,  and  fall  to  the  ground. 
Stronger  shoots  from  the  crown 
develop  the  su])pressed  buds  be- 
tween the  pairs  of  needles,  which 
with  favourable  spring  -  weather 
grow  into  short  needles,  and  give 
the  shoots  a  bushy  appearance. 
The  height,  growth  and  develop- 
ment of  the  crown  are  thus 
seriously  affected  ;  and  the  pro- 
duction of  cones  being  materially 
reduced  greatly  impairs  the  success 
of  natural  regeneration  of  Scots 
lows  a  hollowed-out  twig  bearing 
be   found   lying  on    the   ground 


PINE-BEETLE. 


269 


in  thousands  after  an  autumnal  storm.  Sometimes  two 
beetles  are  found  in  the  same  twig,  and  some  beetles  hiber- 
nate in  them,  but  this  is  probably  a  rare  occurrence.  Owing 
to  the  loss  of  these  bored  twigs,  the  crowns  of  trees,  if 
repeated!}'  attacked  by  the  pine-beetle,  acquire  a  characteristic 
appearance  which  may  be  recognised  from  a  distance.     They 


tlf  in  tbe 


acquire  the  form  of  the  cypress  instead  of  possessing  the 
usual  dome-like  shape,  and  here  and  there  a  few  side-branches 
which  have  been  spared  may  project  outwards  from  the 
tree  (Fig.  129).  This  curious  aspect  of  the  trees  has 
given  to  the  insect  the  appellation  of  Ilortidanus  naturae 
("  Waldgiirtner  "  or  Pruner). 

Besides  the  direct  damage  (loss  of  increment,  diminution  of 
the  seed-harvest)  inflicted  on  attacked  trees  by  the  reduction 


270  PROTECTION    AGAINST    INSECTS. 

of  their  assimilating  organs,  indirect  damage  is  also  done  b}'^ 
reduction  of  the  cover,  and  consequent  exposure  of  the  soil. 
As  the  cover  of  Scots  pine  woods  is  apt  to  open  out  even 
under  favourable  conditions,  this  form  of  injury  is  very  serious. 

Exceptionally,  the  beetles  in  summer  eat  out  irregular 
longitudinal  galleries  in  the  first  5  to  6  years'  growth  of  shoots 
on  vigorous  12-  to  15-year-old  Scots  pines,  but  without  laying 
any  eggs.  Altum*  states  that  these  galleries,  which  run  partly 
in  the  bast,  partly  in  the  sapwood,  are  only  used  to  harbour 
the  beetles. 

Lastly  the  beetle  does  damage  by  boring  down  for  2  or  more 
inches  to  the  sapwood  of  the  rootstock  of  sound  standing  trees 
in  order  to  hibernate.  If  this  should  happen  on  a  large  scale, 
the  trees  might  die,  or  at  any  rate  would  become  sickly  and 
attract  more  beetles  in  the  ensuing  spring. 

The  pine-beetle  prefers  forests  in  flat  or  undulating  country, 
isolated  trees,  trees  along  the  borders  of  woods,  and  those 
which  have  suffered  from  tire ;  it  is  also  common  near  timber- 
depots.  Like  all  bark-beetles,  it  prefers  whidfalls  or  trees 
partly  uprooted  by  the  wind,  and  sickly  trees,  but  does  not 
exclusively  attack  such  trees. 

In  a  pine  forest  on  the  peninsula  of  Darss  on  the  Pomeranian 
coast,  which  had  been  flooded  with  salt  water  on  the  12th  and 
13th  November,  1872,  and  the  trees  thus  rendered  sickly,  the 
beetle  appeared  in  such  enormous  numbers  as  to  completely 
destroy  2,500  acres  of  the  forest. 

In  the  spring  of  1892,  about  100  acres  of  pine  wood  was 
burned  near  Caesar's  Camp,  in  Windsor  Forest.  The  next  year 
there  was  a  serious  attack  of  pine-beetles,  the  trees  that  had 
been  singed  by  the  fire  having  multitudes  of  larvae  between 
their  bark  and  wood.  These  trees  had  all  to  be  felled,  while 
the  surrounding  forest  trees  were  pruned  in  the  most 
unsiglitly  manner  by  the  beetles. 

d.  Protpclivc  nuJrf!. 

i.  Timely  and  frequent  thinnings  of  pine  woods,  and  quick 
removal  of  all  sickly  trees. 

*  "  Ein  neucr  Sommcraufenthalt  von  M.  p'ni'i perdu,''  /rifiirhr.fr.  Frxf.  v.  Jf/ilii\, 
]87!t,  page  204, 


.MYKLOI'HIF.US    MINOR. 


271 


ii.  Clearance  of  the  felling-areas,  at  the  latest  by  the  middle 
of  April ;  removal  from  the  wood  of  all  valuable  timber  with 
thick  bark  before  the  beetles  emerge. 

iii.  Uprooting  of  stumps  and  broken  trees.  If  for  any  reason 
this  is  not  practicable,  they  must  at  any  rate  be  barked, 

iv.  Pine  woods  injured  by  fire  must  be  felled. 

V.  All  insect-eating  mammals  and  l)irds  must  be  protected, 
especially  those  referred  to  under  T.  Uipofjmphus,  L.  (page  244). 

c.  Remedial  Measures. 

i.  Trap-trees  should  be  felled  from  February  till  September 
so  as  to  keep  up  a  supply  of  trees  which  are  not  too  dry  for  the 
beetles  to  breed  in.  Thick-barked  trees  injured  by  storm, 
snow,  caterpillars  or  fire  should  be  selected  ;  some  of  them 
should  be  barked  in  the  middle  of  May  and  others  at  intervals 
of  4  to  6  weeks,  and  the  bark  hurned  in  2)its. 

ii.  All  standing  trees  containing  larvae  or  pupae  should  be 
felled  and  barked  and  the  bark  burned. 


4.  Mj/dnphUus  minor,  Hart. 
a.  Desa-iption. 

Beetle  3"8  to  4  mm.  long ;  closely  resembling  the  preceding 
species  in  appearance,  but  with  the  bristle- 
bearing  tubercles  continued  on  the  second 
interstice  of  the   elytra   up    to   its   apex, 
as  on  the  other  interstices. 

//.  Life-Jiisforij. 

Season  for  fiif/ht.  April  and  May,  about 
8  to  10  days  later  than  the  preceding 
species. 

Standing  Scots  pines  are  selected  for 
breeding,  but  as  a  rule  the  thickly  barked 
lower  part  of  the  stems  is  avoided,  and  the 
upper  portion  where  the  bark  is  thinner 
is  chosen.  The  young  brood  requires  for  its  development 
somewhat  fresher  material  than  in  the  case  of  M.  pinipcrda. 


272 


PKOTKCTIOX    AOAINST    INSECTS. 


The  larvae  hatcli  in  June,  and  pupate  in  July  in  a  chamber 
made  in  the  sapwood. 

The  beetles  emerge  in  July  and  August,  and  generally  pair 
in  the  following  year.  Those,  however,  which  appear  early, 
usually  produce  another  brood  within  the  year,  as  in  the  case 
of  the  preceding  species. 

Generation  single  or  double.  The  beetle  is  found  in  com- 
pany with  the  former  species,  but  is  rarer,  or  at  any  rate  more 


l.,c 


1,!#V 


^Jf0M 


^)i;p 


]junows  of  31.  niiuor,  Iliirt.,  on  \mK 


{.\„i 


localised.  In  the  British  Isles  it  has  only  been  found,  and 
that  very  rarely,  in  the  Dee  district  of  Scotland,  but  it  is  so 
like  the  much  commoner  M.  inniperda,  L.,  that  it  is  probably 
overlooked. 


r.   Relations  to  Uie  Forest. 

M.  minor,  Hart.,  chiefly  attacks  the  Scots  pine,  but  has 
also  been  found  on  the  spruce.  It  prefers  poles,  but  may 
attack  50-  to  70-year-old  trees.  The  mother-galleries  are 
large,  regular,  double-armed,  and  horizontal,  with  a  rather 
long  entrance-burrow,  and  groove  the  sapwood  deeply  (Fig.  131). 


ASH    BARK-BEETLE. 


273 


The  injury  which  its  breeding  causes  is  greater  than  that  of 
H.  pinipcrda,  as  the  circulation  of  the  sap  is  more  endangered 
by  these  horizontal  galleries.  It  is  not  therefore  surprising 
that  quite  sound  trees  are  killed  by  it,  or  at  any  rate  become 
stag-headed. 

The  larval  galleries  are  short,  not  very  numerous,  and 
terminate  in  a  deeply-cut  pupal  chamber.  This  beetle,  unlike 
the  preceding  species,  is  said  not  to  confine  itself  to  the  borders 
of  a  pine-wood,  but  to  be  found  deeper  in  its  interior. 

M.  minor  also  bores  into  the  pith  of  young  pine  shoots  in 
the  same  way  as  M.  pinipenla. 

d.  Protective  Rides. 

As  for  .V.  piiiipcrda,  but  the  trap-trees  must  have  thin, 
smooth  bark. 


5.  Hi/h'sinus  fraxini,  Fabr.   {Ash  Bark-heetle). 
a.  Description. 

Beetle  2  to  3  mm.  long,  short  and  thickset ;  pitchy-brown 
or  reddish,  variegated  with  short,  close- 
lying,  ashy  and  fuscous  scales,  forming  a 
series  of  irregular  transverse  bands  on 
the  elytra.  Prothorax  transverse,  finely 
granulate  ;  elytra  with  fine  but  distinct 
punctured  striae  ;  legs  piceous  with  the 
tarsi  reddish,  antennae  ferruginous. 


—         ^ 

',.    132. — Ilyksimis 
fraxini,  Fabr. 


b.  Life-historij. 

Flif/ht  period  at  the  end  of  April  and 
beginning  of  May. 

The  eggs  are  laid  on  the  branches  and 
stems  of  healthy  ash  trees,  as  well  as  on 
dead  and  felled  trees.     The  larvae  hatch  in  May,  and  develop 
in  July  to  the  perfect  insects,  which  pass  the  winter  in  irregular 
borings  in  the  bark. 

Generation  usually  single,  but  has  been  observed  double  in 
Elsass,  the  second  flight  from  end  of  August.  Common  and 
generally  distributed  throughout  the  British  Isles. 

F.P.  T 


274 


PROTECTION    AGAINST    INSECTS. 


r.  Eelaiionx  to  the  Forest. 

The  beetle  bores  into  the  bast  of  ash-poles  and  trees, 
constructing  extremely  regular,  double-armed,  horizontal 
galleries,  with  a  short  entrance-burrow  (Fig.  133,  a).  The 
larval  galleries  are  short  but  close  together,  cutting  deeply 
into  the  wood,  and  are  always  very  regular  (Fig.  133,  h).  The 
pupal  chambers  are  in  the  wood  (Fig.  133,  c).  The  beetles  eat 
their  way  out  in  August,  making  numerous  perforations,  so 
that  the  bark  is  riddled,  as  if  by  shot.     Once  a  tree  has  been 


Fig.  133. — Burrows  of  H./raxini,  Fabr.,  on  asli  sapwood.     {Natural  size.) 
a  Mother-galleries,     b  Larval  galleries,     c  Pupal  chambers. 


attacked,   numerous  galleries   are    excavated   in  it  one  over 
the  other. 

The  beetle  prefers  quite  sound  trees,  according  to  Hess,  and 
kills  them,  but  Miss  Ormerod  says  that  the  damage  is  chiefly 
done  to  decayed  or  sickly  trees.  This  insect  also  attacks  large 
ash-trees  standing  in  the  open,  boring  down  to  the  bast  in  order 
to  hibernate  there,  and  such  winter-quarters  are  generally 
occupied  again  in  the  succeeding  autumn  by  more  numerous 
beetles,  so  that  rough,  scabrous,  rosette-like  prominences  are 
eventually  formed  on  the  bark.  It  has  occasionally  been 
observed  to  attack  the  robinia  and  apple-trees,  but  its  galleries 
are  then  vertical  rather  than  horizontal.  It  may  be  laid  down 
as  a  general  rule  that  the  smaller  the  branches  which  are 


HYLESINUS    CRENATUS. 


375 


attacked,  the  more  do  galleries  which  are  normally  horizontal 
tend  to  become  vertical. 

In  the  ecclesiastical  forests  of  Temeser  Banat,  in  Hmigary, 
the  ash  woods  have  since  1888  been  seriously  attacked  by 
this  beetle.  By  the  summer  of  1890,  17  per  cent,  of  the  trees 
of  a  total  standing  crop  of  2,570,000  cubic  feet  were  killed. 

(L  Economic  Rules. 

i.  Selection  of  suitable  localities  for  planting  ash-trees,  and 
attention  to  such  rules  of  management  as  will  keep  the  trees 
healthy. 

ii.  All  infested  trees  should  be  barked  in  June  and  July,  and 
their  bark  and  branches  burned. 

iii.  Trees  attacked  may  be  tarred. 


G.  Hijlcsinns  rittattts,  Fabr. 
Beetle  similar  to  H.  fraxini,  Fabr.,  but  only  1^  to  2  mm. 
long ;  with  a  white  stripe  on  each  elytron  extending  from  the 
shoulder  to  the  middle  of  the  suture  and  enclosing  a  common 
oval  dark  patch  ;  it  makes  double-armed  horizontal  galleries 
in  the  elm. 


7.  IlijlesiiiHS  crenatiis, 
a.  Descrijilion. 

Beetle  5  to  6  mm.  long;  ovate, 
blackish  -  brown  or  black,  its  under 
surface  hairy. 

Thorax  tapering  in  front,  distinctly 
broader  than  long,  thickly  and  coarsely 
punctured  ;  elytra  broadest  at  the 
middle,  obli(j[uely  and  not  strongly 
declivous  behind,  with  coarse  punc- 
tured striae,  the  interstices  granulate 
and  furnished  with  short  black  hairs ; 
abdomen  curved  upwards  towards  the 
apex. 

0.  Life-hislurij. 

Similar  to  that  of  H.  fraxini;  but 
the  generation  is  said  to  be  double. 


Fabr. 


Fig.  1U4. — ll>jks'i)ius 
cfcnatus,  Fabr. 


The  flight-period  is  at 
t2 


276 


PROTECTION    AGAINST    INSPXTS. 


pf^'?™^'''rTli7Tr^WlJfJi 


the  beginning  of  April,  and  again  in  Octol)ei-.  "When  pairing 
takes  place  late  in  the  spring  (May  and  June)  the  generation 
is  only  single. 

c.  llcJalions  io  Ihe  Forest. 

This  beetle  attacks  the  ash  almost  exclusively,  and  prefers 
large  trees  with  fissured  bark.  The  female  makes  short, 
slightly  bent,  generally  two-armed 
galleries.  The  two  arms  are  gene- 
rally of  unequal  length  and  inclined 
at  an  acute  angle ;  sometimes  only 
one  is  present.  The  larval  burrows 
run  at  first  upwards  or  downwards, 
that  is,  at  right  angles  to  the 
mother-galleries,  gradually  curving 
and  becoming  horizontal ;  they  are 
of  great  length,  and  are  often 
abruptly  bent  on  themselves  once  or 
twice  in  their  course.  Fig.  135 
shows  the  appearance  of  a  gallery, 
in  which  boring  beetles  as  well  as 
larvae  may  be  distinguished ;  the 
latter  so  closely  packed  that  their 
galleries  have  coalesced.  It  is, 
however,  hardly  typical  of  the 
species.  If  the  ?  do  not  lay,  they 
bore  simple  tunnels,  frequently  just 
under  the  outermost  bark,  which 
then  generally  splits  and  flakes  oflf 
over  the  point  of  attack.  Excep- 
tionally the  beetle  has  been  found 
attacking  old  oak-trees  in  the  Russian  Chersonese;  the 
galleries  in  this  case  may  be  three-armed. 

The  attacks  of  this  insect  may  be  treated  as  for  ILj'vaxbn. 


Fig.  13u. — Burrows  of  II.  ci-cnu' 
Ins,  iu  ash  bark. 
a  Eutrauce-liole. 
b  Mother-galleries. 
c  iJeethis  excavating  g 
d  Boriu"-  larvae. 


.lie 


C     SUBFAJIILY    SCOLYTINI. 

Description  of  Siihjitinilij. 
This    sub-family    contaiiis   a   single   genus,    Scolytas,    the 
species  of  which  possess  a  projecting  head  with  a  short,  broad 


ELM    r.ARK-REETLE. 


277 


rostrum.  Antennal  funiculus  7-jointecl.  First  tarsal  joint 
much  shorter  than  the  succeeding  joints  together,  the  third 
bilobed.  Elytra  scarcely  declivous  behind.  Under  surface 
of  abdomen  flexed  upwards  from  the  base  of  the  second 
segment. 

They  breed  exclusively  bet\Yeen  the  wood  and  bark  of  broad- 
leaved  trees,  and  sometimes  make  very  regular  galleries,  which 
generally  cut  deeply  into  the  sapwood.  Pupal  chambers  in 
the  outer  layers  of  the  sapwood. 

1.  Scoli/his  GcoJ'rojji,  Goeze  {Elm  Ihtrk-hcctlc). 
a.  Desr  rip  lion. 
This  bretlc  is  4  to  5  mm.  long,  black,  with  the  elytra  brown  ; 
antennae  and  legs  reddish  brown.  Front  of  head  and  rostrum 
without  any  carina.  Thorax  broader  than  long,  punctured, 
the  punctures  becoming  weaker  towards  the  middle  of  its 
upper  surface.  Suture  of  the  elytra  depressed  from  the  base 
to  its  middle ;  their  interstices  broad,  w^itli  two  or  three  rows 
of  punctures.  Third  and  fourth  abdominal  segments  in  both 
sexes  with  a  small  tubercle. 


b.  Lifo-history. 

Flif/ltt  at  the  end  of  May  and  June,  and  sometimes  again  in 
August. 

The  eggs  are  laid  in  the  bark  of  elms, 
by  preference  in  sickly  trees. 

The  larvae  appear  in  July  and  the 
beetles  fly  in  August,  and  at  once  pro- 
ceed to  pair.  The  larvae  of  the  second 
brood  hibernate  in  their  borings,  and 
pupate  in  the  following  spring,  gene- 
rally in  the  bark  or  less  frequently  in 
the  sapwood. 

The  beetles  of  this  brood  come  out 
at  the  end  of  May.  The  holes  of  exit 
are  about  the  size  of  No.  5  shot. 

The*generation   is  usually  double  on  the  Continent,   and 
apparently  so  in  England  in  warm  seasons.     But  in  Britain, 


Fig.  13G. — "^rohjtits 
Ocoffroyi,  Goeze. 


278  PROTECTTOX    AOAIXST    INSECTS. 

where  the  insect  is  common  south  of  Scotland,  a  sinf^'le 
generation  is  more  usual,  the  larvae  which  hatch  in  ]\[ay  or 
June  becoming  full-fed  at  the  end  of  July  and  remaining  in 
the  tree  throughout  the  winter. 

c.   Pieltiiiojis  lo  iha  For(>f<t. 

The  beetle  attacks  old  and  young  elm-trees,  and  sometimes 
also  the  ash. 

The  mother-gallery  is  broad,  short,  ascending  and  vertical, 
about  2*5  mm.  broad,  and  with  1  to  2  air  holes.  The  second- 
ary galleries  ramify  from  it  at  right  angles  in  a  fairly  regular 
manner,  lie  close  together,  are  long,  sometimes  extending  for 
more  than  4  in.,  gracefully  curved,  and  somewhat  broader  at 
their  ends  than  the  primary  gallery.  The  pupal  chambers 
when  the  bark  is  thin  are  excavated  partly  in  the  sapwood. 

Tliis  beetle  especially  attacks  elms  in  the  neiglibourhood  of 
large  towns  ;  thus  in  1842,  elms  in  Eegent's  Park  were  infested, 
and  in  1870,  many  elm-trees  that  had  been  weakened  by  a 
raising  of  the  groundwater  level  were  killed  in  ]3erlin. 

d.  ProiecHvB  PuJfs. 

As  a  preventive  measure,  elms  in  avenues,  parks,  etc.,  may 
be  smeared  with  Leinweber's*  composition. 

All  stems  attacked  by  the  beetle  should  be  felled,  beginning 
in  July,  and  the  bark  burned.  Trees  that  have  been  felled 
may  be  used  as  traps,  and  treated  accordingly. 

2.  Sroliftus  iiitricatiis,  Eatz. 

a.   Dfsrnpfioii. 

Beetle,  3 — 4  mm.  long;  Ijlack,  with  the  elytra,  antennae  and 

legs,  pitchy-red,   or  brown  ;    the  former  with  close  rows  of 

punctures,  the  interstices  narrow,  closely  wrinkled,  the  suture 

depressed  round  the  scutellum  ;  abdomen  unarmed. 

•  5  lbs.  tobacco,  mixed  with  J  pailful  of  hot  water,  are  kept  hot  for  24  hours  ; 
the  water  is  then  squeezed  out  of  the  tobacco  and  mixed  with  J  pailful  of 
bullock's  blood,  1  part  of  slaked  lime  and  Ifi  parts  of  cow-dung.  This  is  kept 
in  an  open  tub  and  stirred  once  a  day,  and  used  after  fermentation  lias  set  in. 
The  rough  bark,  moss,  etc.,  is  trimmed  off  the  tree,  and  the  latter  painted  with 
the  mixture  for  three  successive  days,  until  a  crust  is  formed  which  the  rain 
will  not  wash  off. 


LONGICORN   BEETLES. 


279 


Fig.  VM.St'oli/lita 
iiiiriccilits,  Ratz. 


I).  Life-hhtori/,  etc. 

It  lays  its  eg^^s  on  oaks,  but  otherwise  resembles  the  elm 
beetle  in  its  mode  of  life.  It  has,  however,  only  one  generation 
in  the  year. 

It  attacks  several  species  of  oak  and  more  rarely  the  beech, 
and  it  prefers  young  stems  and  branches     • 
to  older  parts  of  trees. 

The  beetle  bores  a  simple  gallery ;  the 
larval  galleries,  30  to  40,  run  partly  up- 
wards and  partly  downwards,  and  are  long 
and  narrow.  The  pupal  chambers  groove 
the  sapwood  superficially.  The  beetles 
attack  perfectly  healthy  oak  saplings  and 
kill  them. 

In  the  Bois  de  Yincennes,  several  years 
ago,  about  50,000  30-year-old  oaks  were 
killed  by  this  beetle,  which  breeds  freely 
in  oak-posts  which  have  not  been  barked, 
and  are  used  for  fences. 

Care  in  the  management  of  plantations  of  saplings,  and 
avoidance  of  unbarked  wood  in  palings,  are  the  chief  protective 
measures  available. 

Two  other  species  of  Scolytus,  S.  pruni,  Eatz.,  and  S.  rugu- 
losns,  Eatz.,  the  latter  a  very  small  species,  are  especially 
attached  to  fruit-trees,  plum  and  apple.  Both  are  locally 
common  in  England,  and  sometimes  injurious,  but  they  are 
not  important  to  the  forester. 

Family  YIII. — Cerambycid.t:  (Longicorn  Beetles). 
Description  of  Family. 

Longicorn  beetles  are  elongate,  and  generally  of  large  or 
moderate  size,  with  a  cylindrical  thorax,  often  spined  at  the 
sides  ;  elytra  somewhat  depressed,  wider  at  the  shoulders  than 
the  thorax,  and  tapering  behind. 

Antennae  filiform  or  setaceous,  rarely  serrate,  and  always 
becoming  thinner  at  the  ends,  usually  very  long,  with  11  or 
more  joints,  the  second  joint  always  the  shortest. 

Legs  slender  and  long.  Tarsi  four-jointed,  the  three  basal 
joints  flattened  and  spongy  beneath,  the  third  bilobed. 


280 


PROTECTION    AflAlNST    INSECTS. 


Abdomen  with  5  segments.     Generation  usually  biennial. 

Larvae  soft,  white  or  yellow,  usually  cylindrical,  rarely  some- 
what flattened,  with  i^rojecting  broad  thoracic  segments,  of 
which  the  first  at  least  is  furnished  above  with  a  horny  plate. 
Their  feet  consist  of  six  minute  tubercles,  or  are  entirely 
absent. 

Pupae  fusiform,  and  recognisable  by  the  long  horns  bent 
down  in  a  curve  from  the  head. 

Flight-holes  transversely  oval. 

The  larvae  generally  live  under  bark  and  in  wood,  but 
usually  only  in  broken  trees  or  in  stumps  ;  a  few  species  are 
found  in  beams  of  houses.  Their  attack  is  of  a  secondary 
nature,  as  they  bore  into  trees  killed  by  bark-beetles  and  other 
insects,  but  on  account  of  the  large  size  of  their  galleries,  and 
the  quantity  of  boring  dust  which  exudes,  it  easily  attracts 
attention. 

On  sunny  days  the  beetles  may  be  found  on  flowers,  shrubs, 
and  felled  trees ;  the  females  do  not  make  mother-galleries. 

Longicorn  beetles  are  rare  as  a  rule  in  the  British  Isles,  and 
most  of  the  species  found  are  small  and  of  little  or  no  economic 
importance.  In  tropical  countries  they  play  an  important  part 
in  the  destruction  of  fallen  and  decaying  timber. 


1.  Saperda  carcharkis,  L.     {The  Larf/e  Poplar  Lomiicorn.) 

a.  Description. 
Beetle  23  to  30  mm. 
long,  gre}'  or  brownish 
yellow,  dotted  with 
many  shining  black 
points.  Thorax  short 
and  cylindrical.  Elytra 
with  the  shoulders 
prominent,  narrowed 
posteriorly  and  bluntly 
spined  at  the  apex. 
Larva  extending  up  to 
36  mm.  in  length,  with- 
out legs,  cylindrical, 
yellowish  white,  with  the  mandibles  and  segmental  shields 


''ig.  13S. — Sdjitrda  C((n]iari(is 
a  Imngo.     Ii  Larvii. 


THE    LARCE    POPLAR    LONGICORN. 


281 


brown,  the  latter  on  the  dorsal  surface  of  segments  8 — 10, 
and  the  ventral  surface  of  segments  2 — 10. 


h.  LifO'huiory. 

Season  for  Jli(j]it:   June  and  July. 

The  eggs  are  laid  in  June  in  crevices  in  tlie  hark  of  poplars, 
especially  near  the  ground. 

The  larvae  emerge  in  July  and 
August,  and  live  and  hibernate  in  the 
wood,  pupating  in  May  of  the  3rd  year. 

The  pupae  lie  head  downwards  in 
a  chamber  blocked  with  a  plug  of 
wood-dust. 

The  imagos  emerge  in  June  of  the 
third  year. 

Generation  biennial.  The  insect  is 
rather  common  in  a  few  parts  of 
Great  Britain,  chiefly  in  the  Eastern 
Counties. 


r.  Rclatiom  to  the  Forest. 

The  larvae  bore  into  young,  healthy 
poplars,  and  also  into  willows  ;  aspen 
and  black  poplar  up  to  20  years  old 
are  specially  attacked.  Seedling-trees 
are  liable  as  a  rule  to  be  attacked 
from  their  5th  year,  and  suckers  from 
the  3rd  year. 

The  larvae  make  vertical  galleries, 
which  reach  the  centre  of  the  tree :  these  become  gradually 
filled  with  wood-dust,  which  is  forced  out  of  the  tree  l)y  the 
grubs,  through  a  l)ore-hole,  and  becomes  heaped  up  at  the 
base  of  the  plants.  The  stem  is  attacked  near  the  ground 
and  reacts  by  developing  a  large  irregular  swelling,  the  bark 
of  which  is  fissured.  Such  perforated  saplings  are  easily 
broken  by  the  wind.  This  insect  is  chiefly  of  importance 
where   poplars   are   grown   on   a  large  scale,  as  in  France. 


Fig.  139. — Larval  burrows 
of  iS'.  carcharUts.  li.,  in 
tlie  stem  of  a  young  poplar. 

{Natvral  size.) 
(I  Plus:  of  borinsr  dust. 


282  PROTECTION    AOAINST    TXSECTS. 

It  is  sometimes  associated  witli   Srsia  apifonuia,  Fabr.,  and 
Cossii.H  lit/nij^erda,  Fabr. 

The  beetles  in  June  and  July  eat  roundish  holes  in  poplar 
leaves,  but  this  injur}'  is  unimportant. 

(I.  Frofcctire  Rides. 

i.  Poplar-nurseries  should  not  be  established  near  older 
poplars. 

ii.  Poplar-saplings  liable  to  attack  may  be  smeared  in  June 
up  to  5  feet  in  height  from  the  ground,  with  a  mixture  of  clay 
and  cow-dung,  or  Leinweber's  composition  (page  278).  This 
treatment  is  to  be  recommended  for  nurseries. 

f.  Remedial  Meafiure>t. 

i.  Collection  of  the  beetles  by  shaking  the  saplings  in  June 
and  July. 

ii.  Felling  and  removal  of  all  attacked  saplings  before  the 
beetles  emerge. 

2.  Saperda  popidnra,  L.   (Small  Poplar  Loufiicnrn). 

a.  Descriplion. 

Beetle  8 — 13  mm.  long,  greenish-grey  to  dark  brown, 
covered  with  yellow-grey  pubescence  ;  thorax  with  3  lines  of 
pubescence ;  elytra  with  the  median  line,  and  a  broad  lateral 
stripe,  and  three  or  four  spots  on  each  side  pubescent. 
Antennae  blackish,  and  each  segment  up  to  two-thirds  of 
the  length  of  the  antennae  with  grey  pubescence.  Larva 
13 — 15  mm.  long,  yellowish  and  resembling  that  of  the 
preceding  species. 

b.  Lifo-]iislonj. 

The  female  deposits  her  eggs  in  May  and  June  in  cracks  on 
the  bark  of  young  aspens,  less  commonly  on  other  species  of 
poplar,  sometimes  on  willows.  Seedlings  of  2  to  (>  years  old 
and  suckers  are  preferred. 

Generation  biennial.  The  larva  hatches  in  July,  bores 
through  the  bark  and  eats  a  circular  gallery  round  the 
sapwood.     The  stem,  usually  one  of   the  smaller  branches, 


SAPERDA    POPULNEA. 


283 


reacts  by  forming  a  gall-like  swelling,  which  however 
found  on  willows. 

In  the  second  summer  the  larva  changes  its  course, 
upwards  along  the  middle  of  the  stem 
for  about  an  inch.  The  flight-hole  is 
circular  and  situated  on  the  swollen 
portion.  Pupation  in  April  of  the 
third  3'ear. 

This  insect  is  usually  found  in  open 
sunny  places,  and  is  not  uncommon 
in  the  Midlands  and  south  of  England. 
It  seldom  kills  the  trees,  but  cripples 
the  branches  and  prevents  growth. 
"Where  it  is  abundant,  hardly  a  branch 
can  be  found  free  from  its  galls. 


IS  not 
borinfj 


c  .  Remedial  Measures. 

Collection  of  the  beetles  in  June  by 
shaking ;  cutting  and  burning  the 
attacked  branches  during  the  winter. 

The  Musk-beetle,  Cerambyx  mos- 
chatus,  L.,  is  a  handsome  dark  or 
bluish-green    longicorn    with    bright 

metallic  lustre,  it  exhales  a  strong  odour  of  musk.  Its  larvae 
live  in  rotting  willow-stems,  and  also  in  old  osier  stools,  where 
it  may  do  some  damage. 


Figs.  140  and  141. — Burrows 
of  .S'.  populnca,  L.,  in  an 
a.spen  twig. 

External  view  with  two  flight 
holes.  View  of  interior 
with  the  larval  hurrows 
exposed. 


F.uiiLY  IX. — Chrysomelid.-r  (Leaf-Beetles). 
1  inscription  of  Famihj. 

Lcaf-hcetles  are  small  or  of  moderate  size,  convex  and  short, 
of  an  oval  or  hemispherical  shape. 

Antennae  filiform,  bead-like,  or  slightly  thickened  at  the 
ends,  11-jointed.  Legs  usually  short,  strong,  sometimes 
framed  for  jumping;  tarsi  4-jointed,  spongy  below,  the  3rd 
joint  bilobed.    Abdomen  with  5  segments.    Generation  simple. 

The  larvae  are  short,  flattened,  usually  either  parti-coloured 
or  black,  with  G  legs,  the  last  segment  usually  with  a  retractile 
process.    Pupae  thickset,  sometimes  hanging  upside  down  from 


•284 


PROTECTTOX    AOAIXST    IX^^ECT^ 


leaves.     Some  specief?  are  vei\y  injurious,  both  tlie  imago  and 
larva  eating  the  leaves  of  broadlcaved  trees. 

1.  C]n-i/somcla  populi,  L.  {Red  Pnplttr-hrii'  Beetle), 
a.  Def<rri/)/ion. 
Beetle  10  to  12  mm.  long,  of  an  obovate  shape,  blackish-blue, 
the  elytra  brick-red,  their  extreme  tip  black ;  thorax  narrower 
than  the  elytra,  its  sides  rounded,  l^roadiy  raised  and  coarsely 
punctured ;  antennae  short,  compressed,  thickened  towards 
the  ends. 


Fig.  142. — Chrysomcla popidi,  L. 
a  Beetle,     h  Larva,     r  Piipu. 

Larva  6-legged,  of  a  dirty  white  colour,  with  many  black 
spots,  and  two  white  lateral  projections  on  the  2nd  and  3rd 
segments. 

Pupa  sharply  narrowed  towards  the  posterior  extremity, 
brownish  yellow,  with  regularly  distributed  black  spots  and 

stripes. 

h.  Life-]ekUtrij. 

The  season  for  Jlif/ht  is  in  May  and  June. 

The  ?  lays  her  yellowish-white  eggs  in  clusters  of  10  to  12,  in 
all  100  to  150,  on  the  under-side  of  the  leaves  of  young  poplars. 

The  larvae  emerge  in  June  or  July,  feed  openly  on  the  leaves, 
and  if  disturbed  exude  a  milky-white  fluid,  with  an  odour  of 
bitter  almonds. 

Pupation  takes  place  in  July  and  August ;  the  pupae  hang 
reversed  from  the  leaves  by  their  pointed  end. 

The  beetles  emerge  by  the  end  of  August,  and  after  October 
hibernate  under  leaves  or  moss,  reappearing  in  the  open  in 
April. 

Generation  annual,  but  frequently  double,  when  the  beetles 
hibernate ;  larvae  appear  in  ]\Iay  and  June ;  pupae  3 — -1  weeks 


CHRYSOMELA    POPULI. 


285 


later,  new  beetles  10  days  later.  Fresh  larvae  in  August,  the 
second  generation  closing  in  the  middle  of  September.  Locally 
common  in  many  parts  of  the  British  Isles,  chiefly  in  South 

England. 

r.  Relations  to  the  Forest. 

The  insect,  both  in  the  larval  and  beetle  stages,  attacks 
young  poplars  and  sometimes  aspen  shoots.  Occasionally 
they  are  found  in  osier-beds,  especially  on  Salix  pur- 
purea, L.,  and  S.  pen- 
tamlra,  L.,  and  to  a 
less  extent  on  S.  rubra, 
L.,  etc.  The  larvae 
attack  the  leaves,  which 
are  completely  skele- 
tonised, the  parenchyma 
being  eaten  and  the 
veins  left  intact.  The 
imago  eats  holes  out  of 
the  leaves. 

The  attacks  last  from 
June  to  August. 


(l.  Proteclii'c  Rules. 
Collection      of      the 


Fig.  li-.i.—C.populi,  L. 
a  Leaf  bitteu  by  beetle.     *  Leaf  bitteu  by  larvae. 

beetles  on  to  cloths  by 

beating  the  trees  in  May  and  June,  and  again  in  August  to 

September. 

C.  treuiulae,  Fabr.,  is  somewhat  smaller  than,  and  greatly 
resembles  the  above  species,  but  has  no  black  tips  to  its  elytra. 
It  is  the  more  destructive  of  the  two,  sometimes  completely 
destroying  the  foliage  and  shoots  of  young  aspen.  It  also 
attacks  osier-willows,  especially  Salix  purpurea. 


2.  Chri/somela  cubjatissiiua,  L.  {U'illou-  Beetle).* 
a.   Deacription. 
Beetle  4  to  5  mm.  long,  oblong-oval,  of  a  bronze  or  green 
tint,  sometimes  coppery  or  indigo-coloured,  violet  or  black. 

*    \'iiie  Miss  Ormcrud,  op.  cit.,  pages  270  to  276. 


286  PROTECTION    AGAINST    INSECTS. 

Elytra   regularly  punctate-striate.      Larvae   vary   in   colour, 
often  nearly  black  above,  with  an  olive-green  middle  line, 

yellowish  below. 

//.  Lifc-liislorii,  dr. 

The  beetles  come  out  in  the  spring  from  their  sheltering 
places,  and  lay  their  eggs  on  the  under-surface  of  leaves  of 
willows — Salix  viminalis,  L.,  *S'.  purpiuea,  rubra,  etc.,  and  also 
on  poplars.  The  imagos  and  larvae  attack  the  young  shoots 
and  leaves,  commencing  with  the  under-surface,  and  eating 
their  way  through  the  leaf,  or  up  to  its  epidermis. 

Pupation  takes  place  in  the  soil.  The  beetle  lives  through 
the  winter,  hibernating  in  various  localities ;  it  is  found  some- 
times high  up  on  willows  in  sheltered  places,  under  the  rough 
bark  of  old  pollards,  in  hollow  stems  of  herbaceous  plants, 
among  the  terminal  shoots  of  neighbouring  young  pine  trees, 
or  on  the  soil  amongst  fallen  leaves  and  old  stumps  of  osiers. 
They  will  also  hibernate  in  the  heaped-up  peel  of  osiers, 
which  should  not,  therefore,  be  left  lying  about. 

Generation  generally  single,  rarely  double.  This  beetle  is 
extremely  common  and  decidedly  injurious.  In  1884,  according 
to  Miss  Ormerod,  in  osier  beds  in  the  Lymm  district,  near  the 
borders  of  Lancashire  and  Cheshire,  it  was  estimated  that 
the  whole  crop  of  osiers  on  50  acres  would  have  been  destroyed 
if  protective  measures  had  not  been  taken. 

<\  Protective  Rules. 

i.  Dragging  across  the  osier-beds  a  rope  weighted  in  the 
middle.  This  operation,  which  should  be  repeated  several 
times,  knocks  off  the  beetles,  which  will  lay  their  eggs  on  the 
ground,  where  they  die. 

ii.  Sprinkling  the  osier-shoots  with  a  strong  solution  of 
wood  ashes,  or  with  Paris  green  (arsenite  of  copper,  see 
page  177). 

iii.  Knocking  the  beetles  off  the  osiers  into  square  tin  vessels 
containing  ashes,  but  this  procedure  must  be  done  repeatedly. 

iv.  Collection  of  the  beetles  in  their  winter  quarters. 

Traps  of  birch-bark,  planks,  etc.,  may  be  put  above  the 
flood-level ;  under  these  the  beetles  collect  in  myriads  for 
shelter,  and  may  then  be  destroyed. 


\VILLO\A'    BEETLE. 


287 


Fig.  144. — C.  vulgatissima,  L. 

Willow  twi-  with  eggs  («),  larvae  (i),  and  beetles  {c)  i/j.     To  the 

right,  beetle  enhirgetl.     From  Eckstein. 


288 


CHAPTER  YII. 

LEPIDOPTERA— BUTTERFLIES  AND   MOTHS.^ 

This  order  is  subdivided  into  Rhopahncra  or  buttertlies,  and 
Ileterocera,  or  moths.  The  former  are  distinguished  from  the 
latter  by  the  possession  of  somewhat  rigid  slender  antennae, 
Avhich  are  clubbed  or  knobbed  at  the  tip  ;  and  by  the  absence 
of  a  frenulum  or  bristle  attached  to  the  base  of  the  hind-wings 
and  passing  through  a  loop  or  rctmaculum  at  the  base  of  the 
fore-wings.  In  the  moths  the  antennae  are  usually  flexible, 
seldom  rigid,  and  are  at  most  thickened  towards  the  apex  with 
no  well-defined  club;  they  usually  possess  a  frenulum. 

Butterflies  are  of  slender  build,  they  fly  by  day  and  are  often 
gaily  coloured. 

They  are  of  no  importance  in  Europe  from  a  forest  point  of 
view,  although  the  larva  of  Pieria  erataefii,  L.,  does  much 
damage  on  the  Continent  to  the  foliage  and  inflorescence-buds 
of  orchard  trees,  as  well  as  species  of  Sorbus  and  Crataegus. 


Heterocera.       Moths. 
Family  1. — Sksiiuak. 
Description  of  Famih/. 
Diurnal  moths  which  fly  rapidly  in  hot  sunshine.     Antennae 
fusiform  ;  2  ocelli.     Proboscis  sometimes  rudimentary.    Wings 
narrow,  more  or  less  hyaline,  and  resembling  those  of  Hymeno- 
ptera  ;  frenulum  present.     Body  stout. 
Generation,  1  to  2  years. 

Caterpillars  cylindrical,  yellowish  white,  with  fine  scattered 
hairs  ;  5  pairs  of  prolegs  ;  head  and  prothoracic  shield  horny, 
and  usually  dark  coloured. 

*  Thu  must  c()ini>rciicusivc\vuik  on  tlic  Britishspcfics  of  l.cijiiluptera  is  '-The 
Lcpulopteni  of  the  British  Jsles,"  by  C.  G.  iJarrclt,  I.oiulon,  18i)2. 


SE81IDAE 


289 


Pupae  slender,  armed  with  circles  of  spines  on  the  abdominal 
segments,  in  a  cocoon  spun  out  of  chips  of  wood. 

The  larvae  live  in  wood,  chiefly  of  broadleaved  trees,  and 
bore  galleries  in  the  stems,  twie:s  or  roots. 


1.  Scsia  apiformis,  Fabr.  {Hornet  Cleancing  Motlt). 

a.  Description. 

Moth  with  a  spread  of  wing  of  35  to  45  mm.  ;  body  dark 

brown,  with  3  pairs  of  bright  yellow  spots,  behind  the  eyes, 

on  the  front  and  on  the  hinder  part  of  the  thorax ;  and  with 

b 


/.  .  Vi 

Fig.  lt.">. — Sisia  apiformis,  Fabr. 
a  Imago.  b  Caterpillar.  c  Pupa. 

the  last  3  segments,  and  the  5th  segment  of  the  abdomen, 
counting  from  the  tail,  bright  yellow.  "Wings  transparent, 
with  rust-red  borders  and  veins.  Caterpillar  with  16  legs,  of 
a  dirty  white  colour,  with  a  reddish  brown  head  and  a  dark 
line  along  the  back.  Pitpa  bro^vn,  with  spines  on  the  back  of 
the  segments  and  apex  of  the  abdomen. 

b.  Life-// is/or  I/. 

The  moth  flies  in  June  and  July. 

The  brown  eggs  are  laid  in  July  in  cracks  in  the  bark  of 
poplars  towards  the  lower  part  of  the  stem.     The  caterpillars 

F.P.  u 


290  PROTECTION    AGAINST    INSECTS. 

appear  in  July  and  August,  pass  two  winters  in  their  galleries, 
and  pupate  in  May  of  the  third  year,  in  a  cocoon  of  wood-dust 
constructed  inside  their  borings,  near  to  the  ground ;  excep- 
tionally in  the  ground  when  the  larva  has  j)ored  low  down 
towards  the  roots  of  the  plant. 

The  imagos  emerge  in  June,  when  the  empty  pupa  cases 
may  be  seen  projecting  from  the  stems. 

The  f/eneration  lasts  two  years.  The  moth  is  widely  distri- 
buted and  often  common  among  poplars  ;  the  injury  caused 
by  the  caterpillars  often  accompanies  that  of  Saperda  car- 
charias,  L.  (page  280). 

r.  Belafions  /o  (he  Forest. 

The  laTva  bores  cylindrical  galleries  in  the  wood  of  poplars, 
especially  of  the  black  poplar  and  aspen.  As  a  rule  it  prefers 
trees  less  than  20  years  old,  but  is  sometimes  found  in  older 
trees.  It  generally  bores  low  down  in  the  tree,  and  its  attack 
can  be  recognised  by  the  wood-dust  which  collects  on  the 
ground  or  blocks  up  the  holes  by  which  the  moth  will  emerge, 
and  through  which  the  pupa  can  push  itself  by  means  of  its 
spines.  The  injured  saplings  are  frequently  broken  by  the 
wind.  The  caterpillar  is  chiefly  injurious  in  nurseries  and 
avenues. 

(I  Protective  Rule.^. 
Saplings  may  be  smeared  as  for  protection  against  the  poplar 
longicorn.     The  moths  should  be  caught  on  the  tree-trunks 
and  destroyed  at  the  end  of  June.     Saplings  infested  with 
larvae  should  be  cut  down. 


Family    II. — Cossidae. 

Description  of  Family. 

Imacjos  of  this  family  of  wood-borers  with  setaceous  or 
bipectinate  antennae ;  without  ocelli ;  the  mouth -parts  rudi- 
mentary. Body  stout,  and  covered  w^ith  close  short  hair^. 
Flight  nocturnal,  the  wings  strong,  and  roof-shaped  when  at 
rest.  Generation  extending  over  2  or  more  years.  Caterpillars 
smooth  or  cylindrical,  and  with  a  few  scattered  hairs.     Pupae 


GOAT   MOTH.  291 

long,  with  rings  of  spines  on  the  abdomen,  in  a  cocoon  spun 
up  of  chips  of  wood. 

The  caterpillars  live  in  the  wood  of  broadleaved  trees. 

1.  Cossus  Ufjniperda,  Fabr.  {Goat  Motlt). 

a.  Description. 

Moth  with  a  spread  of  wing  of  65  to  70  mm.  ( ^ ) — 80  to 
85  mm.  (  $  ).  Body  stout;  head  and  neck  covered  with  yel- 
lowish-grey hair  ;  fore-wings  marbled  with  greyish-brown  and 
light  grey,  with  numerous  dark  brown  transverse  lines ;  hind- 
wings  ashy  grey,  or  greyish-brown.  Abdomen  long  and  thick, 
of  the  same  colour  as  the  wings,  with  whitish  marginal  rings 
to  the  segments. 

Caterpillar  90  to  95  mm.  long,  with  IG  legs,  at  first  reddish- 
yellow,  and  later  cherry-red,  darker  above,  with  a  brown  head, 
and  brown  shield  on  the  prothoracic  segment ;,  it  possesses  a 
very  offensive  smell.  Pupa  stout,  reddish-brown,  with  rings 
of  sharp  spines  on  the  abdominal  segments. 

b.  Life-Jmtory. 
The  moth  emerges  in  June  and  July. 

The  ?  lays  her  eggs,  up  to  25  in  number,  in  a  cluster  deep 
in  cracks  in  the  bark  of  willows  and  other  broadleaved  trees. 

The  caterpillar  hatches  in  July,  and  bores  into  the  wood,  in 
which,  or  sometimes  in  the  ground,  it  pupates  in  May  of  the 
third  or  fourth  year  in  a  large  stifif  cocoon  with  a  smooth 
interior  made  of  particles  of  wood  roughly  spun  together. 
The  moth  appears  3  to  -4  weeks  later. 

Generation,  2  or  3  years.  Found  throughout  Great  Britain 
and  generally  common,  at  least  in  the  south. 

c.  Rclalions  to  the  Forest. 

The  caterpillars  live  chiefly  in  the  wood  of  willows,  but  also 
of  poplars,  alder,  elm,  oak,  birch,  lime,  fruit-trees,  even  the 
walnut,  and  occasionally  in  Scots  pine.  They  prefer  the 
lower  part  of  the  trunk.  The  mode  of  attack  resembles  that 
of  Sesia,  but  many  caterpillars  may  always  be  found  in  the 

u2 


292 


PROTECTION    AGAINST    IXSFXTS. 


Fig.  14(i. —  Conxux  lii/)ii/)(ri/a,  Fiibr. 

n]nrdgo{9).      i>  Caterpillar,  not  fully  grown.      f  Pupa.      </  Cocoon  and 

pupal  exuviae  (after  emergence  of  the  moth). 

same  stem,  sometimes  200  or  more  ;  they  attack  not  only 
sickly  trees,  but  thoroughly  sound  wood,  and  prefer  solitary 
trees  in  hedgerows,  along  forest  borders,  etc.  They  are  very 
voracious,  and  the  wood  which  has  been  attacked  is  useless  as 


GOAT   MOTH.  293 

fimber.  Infested  trees  may  be  easily  recognised  by  the  bad 
odour  due  to  the  caterpillars,  and  by  the  wood-chips  thrown 
out  from  their  borings,  which  are  of  various  sizes  up  to  the 
thickness  of  a  man's  finger. 

d.  Pro/eclit'e  Utiles. 
As  for  Sesia.     Bats,  owls,  and  goat-suckers  attack  the  moths. 
Saplings  which  have  been  attacked  should  be  felled,  split, 
and  burned  with  the  caterpillars  they  contain. 

2.  Cossiis  aesculi,  L.  {Wood-leopard  Moth), 
a.  Descriplion. 
Moth  with  a  spread  of  wings  of  45 — 50  mm.  {3  ),  55 — 65 
mm.  (  $  ) ;  white  with  numerous  round  steel-blue  spots  on  the 
wings  and  six  on  the  thorax ;  abdomen  long,  deep  blue  with 
white  rings.  Larva  naked,  yellow  with  black  warts  and  dorsal 
shield,  l()-legged.     Pupa  with  rings  of  spines. 

//.  Life-hhtorij,  clc 

The  eggs  are  laid  singly  on  saplings  or  branches  of  broad- 
leaved  trees.  The  larva  emerges  in  August,  bores  into  the 
sap  wood  in  the  first  year,  passes  the  winter  in  the  stem,  and 
in  the  second  summer  excavates  a  gallery  running  upwards 
along  the  middle  of  the  wood.  In  this  it  passes  the  second 
winter,  eventually  pupating  under  the  bark.  Generation  bien- 
nial. It  attacks  many  species  of  trees,  maple,  ash,  lime, 
apple,  birch,  beech,  oak,  horse-chestnut,  elm,  poplars  and 
willows,  and  has  even  been  found  in  mistletoe. 

It  is  widely  distributed,  though  rarely  very  abundant; 
sometimes  it  is  rather  common  and  injurious  in  the  neigh- 
bourhood of  large  towns  such  as  London. 

Treatment  consists  in  the  cutting  and  burning  of  the  infested 
stems  and  branches. 

Family  III. — Bombycidae. 

Description  of  Famdy. 
Antennae  short,  pectinate  in  both  sexes  (simply  pectinate 
in  2  ,  doubly  in  J  )  ;  ocelli  usually  absent.     Proboscis  small 


294  PROTECTION   AGAINST    INSECTS. 

and  usually  functionless.  Wings  ample,  sometimes  small  in 
proportion  to  the  size  of  the  body,  roof-shaped  at  rest.  Body 
stout  and  long,  generally  densely  hairy,  usually  larger  in  the 
$  .  Flight  as  a  rule  nocturnal.  Eggs  frequently  laid  in 
clusters,  and  covered  witli  hairs  from  the  tail  of  the  ?  .  Catcr- 
jnllars  usually  hairy,  seldom  naked,  witli  IG  legs.  Pupae  stout 
and  short,  in  a  cocoon  spun  out  of  silk,  often  with  the  larval 
hairs  interwoven. 

The  caterpillars  feed  on  needles,  leaves,  etc.,  and  are  usually 
very  voracious.  Some  of  the  most  destructive  species  of  insects 
in  European  coniferous  forests  belong  to  this  family. 


1.  Gastropacha  pini,  Ochsh.  {Vine  ISIoth).* 
a.  Descripiion. 

Moth  with  a  spread  of  wings  of  60  mm.  {S)  to  80  mm.  (  ?  ). 
Body  thick  and  stout ;  fore-wings  whitish  or  brownish  grey, 
in  the  S  with  dark  reddish-brown  transverse  bands,  and  with 
a  long  unicolorous  patch,  in  which  is  a  white  lunate  spot ;  in 
the  ?  the  bands  and  patch  are  reddish  brown  ;  the  hind- 
wings  in  both  sexes  are  rusty  brown.  The  colouring  and 
markings  of  the  wings  vary  much  in  individual  examples. 

The  caterpillar  attains  a  length  of  80  mm.,  has  16  legs, 
and  varies  in  colour  from  ash-grey  to  reddish  brown,  or  dark 
brown  ;  there  is  a  dark  dorsal  stripe,  and  sometimes  a  series 
of  lateral  white  patches.  It  is  hairy  with  clusters  of  greyish 
bristles,  and  possesses  on  the  2nd  and  3rd  segments  from  the 
head  two  steel-blue  bare  stripes,  which  become  apparent  at 
the  second  moulting,  and  are  very  characteristic. 

Pupa  somewhat  cylindrical,  dark  brown,  enclosed  in  an 
elliptic,  whitish  grey  cocoon,  which  is  pointed  at  both  ends, 
and  of  looker  texture  near  the  head  of  the  pupa  to  facilitate" 
the  exit  of  the  moth. 


*  This  destructive  pest  is  fortunately  not  a  native  of  Great  Britain.  It  iilays, 
however,  so  important  a  part  in  the  literature  of  European  forcstiy,  and  has 
often  proved  so  seriously  destructive,  that  it  has  been  thought  desirable  not  to 
exclude  it  entirely  from  the  piesent  translation,  but  (o  present  an  abridgment 
of  Hess's  account. 


pinf:  moth. 


295 


h.  Lifc-hMonj. 
The  moth  emerges  from  the  cocoon  from  July  till  the  end 
of  August.     It  lays  in  the  second  half  of  July  about  100  to 
200  bluish-grey  eggs,  as  large  as    hempseed,  in  clusters  of 


Fig.  u; 


. — Gastropacha  pint,  Oehsh 
Stale.        b  Female. 


about  25  to  50  in  number,  in  the  bark-crevices  of  standing 
Scots  pines,  usually  at  about  the  height  of  a  man,  or  on  the 
needles  and  shoots  of  young  pines. 

The  caterpillars  hatch  after  20  to  25  days,  about  the  middle 
of  August.     They  at  once  devour  their  egg-shells,  and  then 


293 


PROTPXTION    AGAINST   INSECTS. 


scatter  themselves  among  the  twigs,  where  they'^begin  to  feed. 
When  about  half  grown,  they  descend  the  trees  (in  October 


Vi  Vi 

Fig.  14S. —  Gastropacha  pini,  Ochsli. 

c  Eggs  on  piue-ljurk.     d  Jlature  caterpillar,  feeding  on  the  needles  of  a  jnue-shoot. 

e  Pupa.    /  Cocoon. 

and  November)  to  hibernate  in  moss,  dead  leaves,  etc.,  at  the 
foot  of  the  trunks,  and  remain  there  till  the  next  spring 
(March   or   April),    when    they   climb   again   up    the   trees. 


PINE    MOTH.  297 

Exceptionally  they  may  hibernate  in  the  bark-crevices.  The 
time  of  reascension  depends  on  the  degree  of  warmth  of  the 
season  and  on  the  quarter  from  which  the  wind  is  blowing. 

Pupation  takes  place  at  the  end  of  June  or  beginning  of 
July,  either  on  the  needles  and  twigs  of  the  crown  of  the  tree, 
or  in  the  larger  bark  crevices. 

The  moth  emerges  in  July,  about  20  days  after  pupation. 

Generation  annual ;  but  sometimes  irregular  when  the  insect 
occurs  in  great  numbers.     Very  common  in  Germany. 

r.  Relations  to  the  Forest. 

This  is  the  most  destructive  of  all  insects  to  Scots  pine 
forests  in  Central  Europe,  as  it  may  appear  in  large  swarms 
throughout  the  summer  for  several  consecutive  years,  and  is 
enormously  voracious.  The  caterpillar  also  attacks  the 
Austrian  and  mountain  pines,  and  in  case  of  scarcity  of  food, 
both  the  spruce  and  larch.  It  prefers  60-  to  80-year-old 
trees,  but  when  abundant  it  will  attack  younger  trees,  and 
thickets  of  young  growth  and  plantations. 

The  attack  is  on  the  needles.  When  the  caterpillars  are 
very  young  they  gnaw  the  sides  only  of  the  needles,  but  fully- 
grown  caterpillars  eat  them  down  to  the  sheath,  usually 
leaving  the  latter,  and  in  this  manner  completely  strip  the 
twigs. 

Even  the  terminal  buds  may  be  eaten.  The  older  cater- 
pillars prefer  needles  of  the  previous  year.  A  single  caterpillar 
will  eat  a  needle  in  5  minutes,  and  may  destroy  in  all  1000 
needles.  After  complete  destruction  of  the  needles  and  buds 
the  tree  must  perish,  and  as  a  premonitor  of  death  a  few 
clusters  of  stunted  needles,  termed  rosettes  by  Eatzeburg,  may 
appear. 

The  trees  may  recover,  if  for  a  pole  200  needles,  and  for  an 
old  tree  400  needles,  still  remain  green.  An  attack  com- 
mencing in  April  and  lasting  till  June  is  the  worst,  as  this 
affects  the  formation  of  wood.  An  attack  generally  lasts 
for  3,  occasionally  for  4  years,  and  is  at  its  maximum  during 
the  3rd  year.  Irregularity  in  the  development  of  the  insects, 
and  degeneration  of  the  caterpillars,  which  are  largest  in  the 


298 


PROTECTION    AGAINST    INSECTS. 


first  year  and  become  successively  smaller  and  weaker,  rapidly 
ensue.      At   the   same   time,   insect-parasites   and   bacterial 

diseases  become 
more  and  more 
active,  until  the 
caterpillars  die 
from  these  causes 
in  immense  num- 
bers. 

This  pest  is  most 
dangerous  in  pure 
Scots  pine  forests, 
.  on  sandy  soils,  in 
dry  districts,  and 
in  the  plains  and 
hills  of  North  and 
North-eastern  Ger- 
many, less  so  in 
the  south  and  west; 
it  is  rare  in  moun- 
tainous districts. 

A  succession  of 
warm        summers 
favours  its  multi- 
plication to  an  ex- 
traordinary degree. 
In  the  ten  years, 
1863—72,    in    the 
forests  from  West 
.  Prussia  to  Saxonj'', 
442,500    acres    of 
Scots  pine  forests 
were  attacked,  and 
70,000,000     cubic 
feet    of     timber 
killed.    In  1888-9, 
the  valleys  of  the  llhine  and  Maine,  in  Hesse,  were  ravaged, 
and  the  caterpillars  devoured  the  needles  even  of  10-year-old 
pines. 


Fig.  149. —  Ro.sette-needlcs  {a)  on  Scots   pine,  I'ollowin^j 
defoliation  by  G.  piiii,  Oclish.     [Xalitral  nizc) 


PINE    MOTH.  299 

ih  Protective  Rules. 

1.  Avoidance,  as  much  as  possible,  of  pure  Scots  pine 
forests  in  localities  exposed  to  the  attacks  of  this  insect. 

2.  Careful  search  for  caterpillars,  chiefly  in  November, 
when  they  are  hibernating.  The  soil-covering,'  round  large 
trees  is  raked  up  and  searched,  and  if  6  to  8  caterpillars 
are  found  around  a  tree,  measures  should  be  taken  at  once  to 
destroy  the  caterpillars. 

3.  Careful  management  of  thinnings.  This  removes  sickly 
trees,  admits  the  wind,  which  the  moths  dislike,  and  facilitates 
collection  of  the  caterpillars. 


Fig.  l."(t. — Catuipilhii-  of  the  I'iue  Moth  covered  witli  Microffaster  cocoous. 


4.  Protection  of  enemies :  bats,  badgers,  cuckoos,  owls, 
goat-suckers,  etc.  Titmice,  golden-crested  wrens,  and  tree- 
creepers  destroy  the  moths'  eggs.  A  number  of  ichneumon- 
wasps  and  parasitic  diptera  attack  the  larvae.  Fig.  150  shows 
a  caterpillar  covered  by  the  pupae  of  Mkror/astei-  r/lohatus,  Lr 

e.  Remediat  Measures. 

These  are,  briefly:  The  excavation  of  trenches  in  the  ground 
to  catch  the  caterpillars.  Trenches  are  made  for  the  purpose 
of  either  isolating  attacked  areas,  or  to  catch  caterpillars 
within  the  infested  wood. 

Collection  of  egfjs,  by  scraping  them  from  the  trees ;  but 
this  method  also  destroys  many  ichneumons. 


300  PROTECTION   AGAINST   INSECTS. 

Collection  of  caterpillars. — This  is  undertaken  either  after 
November,  or  by  shaking  the  trees  in  August. 

This  method  is  less  efficacious  than  smearing  girdles  of  tar 
on  the  trees,  as  at  least  half  the  caterpillars  escape. 

Collection  of  impac. — In  June  and  July. 

Collection  of  the  ?  moths. — This  is  carried  out  in  July  in  the 
morning  and  on  cold  wet  days  before  the  eggs  are  laid. 

By  this  means  ichneumons  are  not  destroyed.. 

Girdlin;/  the  trees  with  grease-hands. — This  is  the  best  and 
safest  method  to  adopt  when  the  insects  have  appeared  in 
large  numbers.  It  was  first  employed  in  Silesia  in  1829 
against  L.  monacha,  L.,  and  first  in  1866-7  at  Gliicksburg, 
against  the  present  insect. 

The  details  necessary  to  ensure  success  by  this  measure  are 
carried  out  as  follows  : — 

The  woods  which  have  been  attacked  are  thinned,  in  order 
that  tar  may  not  be  wasted  on  suppressed  stems ;  all  under- 
growth which  might  serve  as  bridges  for  the  caterpillars  is 
cleared  away. 

The  coarse  bark  is  removed  from  the  pines  in  rings  10  to' 
15  cm.  broad,  in  order  to  present  a  smooth  surface  for  the 
tar.     Care  is  taken  not  to  injure  the  bast. 

The  smooth  places  are  covered  with  a  horizontal  band  of 
tar  or  grease  6  to  8  cm.  broad  in  February  or  the  beginning 
of  March,  and  this  operation  is  repeated  at  intervals  of  6  to 
8  days,  or  again  in  April,  when  the  former  application  has 
become  too  dry  to  catch  the  insects. 

Ratzeburg  has  distinguished  experimental  tarring  from 
(jenercd  tarring.  The  former  is  used  on  lines  of  trees  here 
apd  there  throughout  a  wood,  where  a  severe  attack  is  feared, 
and  if  5  or  6  caterpillars  are  caught  on  each  tarred  tree, 
then  a  general  tarring  of  all  the  trees  is  undertaken.  There 
is,  however,  a  danger  that  the  general  tarring  may  come  too 
late,  and  it  is  recommended  to  try  the  experimental  tarring 
in  the  autumn,  and  if  a  general  tarring  is  shown  to  be' 
necessary,  to  take  all  preliminary  measures  for  it  during 
the  whiter.  The  best  tar  is  made  from  pine  roots  and 
stumps ;  it  should  be  of  a  cherry-brown  colour  and  possess 
a  proper  consistency,  be  neither  too  thick  nor  too  thin,  and 


PINE    MOTH. 


301 


I 


must  be  put  on  cold.  Coal-tar  must  not  be  used  for  this 
purpose. 

Certain  compositions  are  also  used  which  are  superior  to 
tar,  such  as  tar  mixed  with  9  to  15  per  cent,  of  resin,  or 
9  to  11  per  cent,  of  acetic  acid.  For  similar  purposes  in 
England,  grease-bands  are  made  of  "cart-grease"  or  mix- 
tures of  Stockholm  tar,  unboiled  linseed-oil,  etc.,  etc. 

In  order  that  a  composition  may  be  really  useful  for  this 
purpose,  it  must  combine  cheapness  with  prolonged  stickiness. 
A  thick  coating  should  always  be  used,  or  else  the  substance 
is  absorbed  by  the  bark. 

In  order  to  spread  the  tar 
a  paint-brush  was-  originally 
used,  but  Boden  and  Kielmann, 
two  German  forstmeisters,  con- 
structed, in  1881,  two  wooden 
spatulas,  which  Fig.  151  repre- 
sents. The  broad  and  grooved 
spatula  is  about  36  cm.  long  and 
5^  cm.  broad  at  the  top,  where 
it  is  grooved  on  one  side,  but 
smooth  on  the  other.  The 
grooving  gradually  slopes  from 
the  handle  to  the  extremity  of 
the  spatula,  where  it  is  5  mm. 
deep.  The  tar  is  taken  from 
the  barrel  on  the  flat  side  of  the 

broad  spatula,  and  spread  on  the  tree  with  the  narrow  spatula. 
The  broad  spatula  is  then  turned  round,  and  the  groove 
pressed  round  over  the  tar.  This  makes  a  smooth  ring  5  cm. 
broad  and "5  mm.  thick. 

The  quantity  of  tar  used  and  the  cost  of  painting  the  rings 
varies  with  the  age  of  the  woods,  and  in  Prussia  averages  40 
to  50  lbs.  per  acre  for  old  wood,  and  50  to  60  lbs.  per  acre  for 
young  wood,  the  average  cost  in  either  case  being  6.s-.  and 
9s.  6(1.  per  acre  for  tar. 

In  1878  in  Plietnitz  in  West  Prussia,  45  millions  of  cater 
pillars  were  destroyed  by  means  of  tar  rings,  at  a  cost  of  Is. 
per  10,000  caterpillars.     In  woods  under  60  years  old  the 


U 


Fiff.  151. 


Front 
View. 

Side 
View. 

3o(leii's 

Spatula. 

302  ■     PROTECTION    AGAINST    INSECTS. 

hibernating  caterpillars  were  collected  at  a  cost  of  20s.  per 
10,000.  The  value  of  the  annual  increment  of  Avood  saved 
was  8s.  per  acre,  as  against  7s.,  the  cost  of  the  tar  rings. 

The  efficacy  of  the  tar  ring  is  less  interfered  with  by  frost 
than  by  great  heat,  as  the  latter  easily  melts  it  and  causes  it 
to  run  down  the  tree.  Most  of  the  caterpillars  which  attempt 
to  cross  the  rings  adhere  to  the  lower  .part  of  them  ;  but  about 
3  per  cent,  of  them,  chiefly  the  larger  ones,  manage  to  cross 
the  rings,  although  of  these  about  59  per  cent;  soon  die  from 
the  effects  of  the  tar,  so  that  only  1-2  per  cent,  of  the  whole 
number  really  survive  and  pass  the  rings. 

The  caterpillars  whose  way  to  the  tree-crowns  is  thus  cut 
off,  return  to  the  ground  and  try  to  find  their  way  to  other 
trees  ;  they  are  therefore  prevented  from  so  doing,  by  isolating, 
by  means  of  trenches,  the  wood  containing  the  tarred  trees 
from  other  woods  which  have  not  been  so  protected. 

Caterpillars  infested  by  ichneumons,  or  fungoid  diseases, 
may  be  introduced  amongst  those  which  are  healthy. 

In  cases  where  the  attack  is  very  bad,  but  localised  over 
a  small  wood  only,  the  soil-covering  is  burned  whilst  the 
caterpillars  are  hibernating,  or  even  the  whole  wood  is  burned, 
measures  being  taken  in  both  cases  to  protect  the  adjoining 
woods  from  the  spread  of  the  fire. 

Robert  Hartig,  in  1871,  experimented  near  Eberswald  on 
the  effects  of  the  (fifferent  methods  of  protecting  the  Scots 
pine  from  these  caterpillars,  with  the  following  results : — 

The  collection  of  hibernating  caterpillars,  as  long  as  the 
moss  and  dead-leaf  covering  is  replaced  in  position,  has  no 
bad  influence  on  the  growth  of  the  tree. 

The  jarring  of  young  trees  in  order  to  knock  oft'  the  cater- 
pillars involves  local  decay  in  the  bast,  and  consequent 
reduction  of  increment. 

Tarring  does  not  hurt  the  trees  in  the  slightest  degree. 


2.  Bomhjx  neustria,  L.   (Laclcey-Moth). 
a.  iJesrri/tlioii. 
Moth  with  spread  of  wings  of  30  to  40  mm.    Body  and  fore- 
wings  ochreous-yellow  or  red-brown,  the  latter  traversed  across 


LACKEY-MOTH. 


303 


their  middle  by  a  darker  band  which  is  bordered  by  pale 
stripes;  hind-wings  somewhat  lighter,  crossed  by  a  vague 
darker  stripe. 

Caterpillar  extending  to  45  mm.  in  length,  with  16  legs, 
marked  with   alternate  stripes   of    blue,    reddish-brown  and 


Fig.  152. — Bomhyx  neustria,  L. 
a  Imago  (y).     h  Egg-riug  on  a  twig,     c  Larva,     d  Pupa. 

white,  thinly  covered  with  long  hairs,  head   blue  with  two 
black  spots. 

Pupa  bluish-black,  covered  with  short  hairs,  in  a  yellowish- 
white  thick  cocoon. 

h.  Life-lihiorij. 

.The  moth  appears  in  July  and  August,  flying  in  the  evening 
and  resting  during  the  day  in  sheltered  places. 

The  $  ,  about  8  days  after  pairing,  lays  from  300  to  400 
brownish-grey  eggs  in  a  close  spiral,  forming  a  cylinder  round 
a  young  shoot. 


304.  'protection  against  inskcts. 

The  caterpillars  hatch  in  April  or  the  heginning  of  ^May, 
and  live  socially  in  companies  of  50  to  100,  until  they  are  full 
grown,  in  web-nests  spun  by  their  joint  labours,  and  increas- 
ing in  size  as  they  grow  up.  They  leave  these  nests  to  feed 
on  leaves,  returning  to  them  in  wet  weather  or  by  night.  In 
line  weather  they  are  fond  of  sunning  themselves.  When 
disturbed,  they  let  themselves  down  to  the  ground  by  threads, 
or  after  hanging  some  time  in  the  air,  draw  themselves  up 
again. 

When  full  grown,  in  June,  they  disperse,  and  spin  cocoons 
among  the  leaves,  or  in  bark-cracks. 

Generation  annual ;  the  insect  is  very  common  over  the 
greater  part  of  Europe  and  in  England. 

r.  Relations  to  the  Forest. 

The  caterpillar  is  found  on  many  trees,  especially  on  apple 
and  other  orchard  trees,  and  on  6ak,  hornbeam,  and  poplars ; 
also  on  elms,  birch,  maples,  willows,  thorns,  briars,  etc. 
Only  ash  and  lime  appear  to  be  spared.  Its  attack  com- 
mences on  the  blossom  and  leaf-buds,  then  extending  to  the 
foliage,  and  lasts  from  the  end  of  April  till  the  beginning 
of  June.  It  is  chiefly  important  in  orchards,  to  which  it  does 
immense  damage. 

(J.  Protertivp  Rules,  etc. 

i.  Protection  of  enemies,  notably  titmice,  the  golden-crested 
wren,  the  cuckoo,  finches,  etc. 

ii.  Pruning  and  burning  twigs  bearing  the  egg-rings  during 
the  winter. 

iii.  Destruction  of  the  young  caterpillars  in  their  webs  by 
crushing  with  gloves,  or  short  brooms,  or  by  cutting  oft'  the 
webs  and  letting  them  drop  into  a  pail  containing  paraftin. 
These  remedies  can  be  economically  applied  in  orchards  and 
tree  nurseries  only. 

3.  Bonihjj.v  2>iidihi()i<la,  L.   {l*alc  Tussock  Moth), 
a.   /Jesrri/)tioii. 
Moth  with  a  spread  of  wings  of  45  mm.  ( J  ),  50  to  GO  mm. 
(?).     Fore- wings  whitish-grey,  sprinkled  with  darker  spots 


150MBYX    PUDIBUNDA. 


305 


and  with  2  to  3  narrow  grey-brown  transverse  waved  lines; 
abdomen  and  hind-wings  somewhat  lighter,  the  latter  with  a 
faint  greyish  band  ;  <?  darker  and  more  spotted  than  the  2  . 
Caterpillar,  when  mature,  about  40  mm.  long,  with  IG  legs, 
at  first  greenish  yellow,  later  becoming  reddish  or  brownish, 
hairy,  with  four  truncated  tufts  of  yellow  or  brownish-grey 
bristles  on  the  -1th  to  the  7th  segments,  separated  by  black 


a  Male. 


Fig.  153. — Bomhi/x  pudiiunda,  L. 
I)  Female.         c  Cateqiillar.        d  Pupa  (dorsal  surface). 


velvety  bands,  apd  with  a  rose-red  pencil  of  hair  on  the  last 
segment. 

Pupa  thick-set,  dark  ])rown,  covered  with  short  grey  hair, 
in  a  yellowish-grey  cocoon  spun  up  with  the  larval  hairs. 


/).  Life- his /■or//. 
The  moth  appears  at  the  end  of  May  or  beginning  of  June. 
Iji  June  the  female  lays  about  100  to  150  bluish-grey  eggs  in 
a  cluster  on  the  l)ark,  generally  low  down,  at  about  1  yard 
from  the  ground,  but  often  a  few  yards  up,  sometimes  on 
twigs  or  dead  wood  on  the  ground,  or  even  on  grass  or 
herbage. 


306 


PROTECTION    AGAINST    INSECTS. 


The  caterpillars  hatch  after  3  weeks,  in  June  or  Jul}',  make 
their  first  meal  off  their  egg-shells,  and  remain  a  short  time 
in  clusters,  with  their  heads  usually  turned  inwards;  about 
the  middle  of  July  they  separate  and  wander  towards  the 
crowns  of  the  trees,  coming  down  to  pupate  in  September. 

Pupation  occurs  at  the  end  of  September,  or  in  October, 
usually  under  dead  leaves,  dead  fallen  wood,  etc.,  on  the 
ground,  in  the  bark-cracks  of  oaks,  Scots  pines,  etc.,  or 
among  herbage  on  the  ground. 


r 


Fig.  154. — Beech-leaf,  eaten  by  the  larva 
of  B.  pudibunda,  L.     {Natural  size.) 


Fig.     155.  —  Oak  -  leaf, 
stripped  by  the   larva 
of  B.  pudibunda,  L. 
(Natural  size.) 


The  generation  is  annual. 

The  caterpillar  is  very  hardy,  and  withstands  snow  and 
cold  well. 


c.  Relations  lo  the  Forest. 
The  caterpillar  lives  singly  on  almost  all  forest  trees,  even 
conifers,  but  has  only   been  observed  in  abundance  on  the 
beech,  and  occasionally  on  the  hornbeam,  oak  or  alder.     It 


BOMBYX   PUDIBUNDA.  307 

prefers  dry,  sunny,  elevated  places,  and  avoids  valleys.  It  has 
often  been  noticed  that  an  attack  commences  simultaneously 
at  several  points  of  high  elevation,  from  which  it  spreads  in 
all  directions. 

It  prefers  40-  to  80-year-old  woods.  The  foliage  is  at  first 
only  skeletonised,  but  after  August  the  leaves  are  almost 
entirely  eaten  and  fall  to  the  ground  in  thousands  after  the 
caterpillars  have  bitten  through  the  petioles. 

In  the  case  of  the  oak,  the  petioles  and  mid-ribs  remain. 

The  damage  done  consists  in  loss  of  increment,  and  reduc- 
tion in  the  production  of  seed,  as  fewer  flower-buds  are 
developed ;  the  quantity  of  beech-mast  is  much  diminished, 
and  the  nuts  are  often  empty. 

This  is  highly  prejudicial  to  beech  forests  under  natural 
reproduction. 

The  insect  prefers  southerly  or  south-westerly  aspects ;  it  is 
very  common  in  North  Germany,  France  and  Belgium 
(Ardennes),  being  found  at  altitudes  up  to  1,300  feet  above 
sea-level.  It  is  tolerably  common  in  Great  Britain,  but  is 
seldom  destructive,  except  in  hop-gardens. 

In  1892,  the  larvae  of  the  pale  tussock  moth  appeared  on 
about  2i  acres  of  forest  in  the  Grand  Duchy  of  Luxem- 
bourg, and  by  October  82  acres  were  leafless.  By  the  end 
of  1893,  5,000  acres  of  beech  -  wood  were  devastated, 
and  the  caterpillars  were  so  numerous  as  to  impede 
locomotives  on  the  narrow-gauge  railway.  Owing  to  the 
increase  of  parasites  and  diseases,  the  epidemic  stopped  in 
June,  1894. 

il.  Proteciivc  Rules. 

i.  Ash,  sycamore  and  conifers  should  be  grown  in  beech- 
woods. 

ii.  Protection  of  enemies  —  crows,  jackdaws,  cuckoos, 
thrushes,  finches,  titmice,  etc.  Ground-beetles  and  ichneu- 
mon-wasps are  very  efficacious,  and  a  spider  {Epcira,  sp.)  has 
been  observed  to  be  extremely  destructive  to  the  insect.  A 
fungoid  disease  due  to  Isaria  farinosa,  Fries,  with  its  higher 
form,  ConUceps  militaris,  Link,  is  also  common. 

x2 


308  PROTECTION   AGAINST   INSECTS. 

c.  Remedial  Measures. 

i.  Collection  or  destruction  of  caterpillars  (end  of  September 
— beginning  of  October),  as  tlie}'  come  do^Yn  the  trees  to 
pupate. 

ii.  Collection  of  pupae  in  the  winter. 

iii.  Girdling  the  trees  with  grease-bands  at  a  height  of  1  lo 
3  3'ards.  This  method  has  given  fairl}'^  good  results  in  the 
Eberswald.  On  3  acres  about  500  caterpillars  per  tree  were 
caught  at  an  expense  of  lis.  per  acre.  Unfortunatel}'  most 
of  the  eggs  had  been  laid  above  the  bands,  and  the  eventful 
destruction  of  all  the  foliage  of  the  trees  was  only  delayed.* 
The  Germans  do  not  now  spend  money  on  destroying  this 
insect,  as  complete  defoliation  lasts  only  one  year  and  the 
attacked  trees  do  not  die. 

4.  Bomhyx  clmjsovrhoca,  L.   {Broivn-tail  Moth), 
a.  Desrrijition. 

Moth  with  a  spread  of  wing  of  30  to  40  mm.  White  ;  the 
inner  margins  of  the  wings  fringed  with  long  hairs ;  fore- 
wings  in  the  3  usually  marked  with  small  black  spots  about 
the  middle  and  towards  the  anal  angle.  Abdomen  brown 
towards  the  tip,  which  is  furnished  in  the  S  with  a  tuft  of 
dark-browii  down,  thicker  and  red-brown  in  the  ?  . 

Caterpillar  35  mm.  long,  10-legged,  with  radiating  tufts  of 
long  yellowish-brown  hairs,  brownish-grey  above,  with  2  red, 
slightly  zigzag  lines  along  the  back  from  the  Gtli  segment 
towards  the  tail,  and  2  vermilion  warts  on  the  9tli  and  lOtli 
segments,  grey  beneath,  with  yellow  spots  and  streaks. 

Pupa  dark  brown,  hairy,  with  pointed  tail,  in  a  brownish- 
grey  cocoon. 

h.  Life- his  (or//. 

The  moth  appears  at  the  end  of  June  and  in  July. 

The  2  lays  200  to  300  brownish-yellow  eggs  on  the  lower 
surface  of  leaves  of  many  broadleaved  trees,  and  covers  them 
with  the  dense  iluff  from  her  tail. 

*  Bombyx  f/ncaitc^i,  Moore,  is  very  destructive  to  foliage  of  the  sal  {Shorea 
rohnsta^  in  Assam,  and  sometimes  loccurs  in  enormous  numbers  over  very  ex- 
tensive areas.  It  also  attacks  the  leaves  of  tea  bushes.  Indian  Museum  Notes, 
Vol.  I.,  page  29. 


BOMBYX    CHRYSORRHOEA. 


309 


The  caterpillars  appear  2  to  3  weeks  later,  usually  in  August, 
and  at  once  spin  web-nests  among  the  neighbouring  leaves. 
In  the  autumn  they  spin  large  caterpillar-nests,  as  big  as  the 
fist,  in  which  they  hibernate,  binding  together  many  leaves 
with  their  threads,  and  thus  forming  chambers  which  they  line 
with  silk  and  fasten  firmly  to  the  twigs. 

Pupation  takes  place  in  June  in  a  thin  greyish-brown  cocoon 
between  leaves. 


I 


Fig.  156. — Bomhijx  chrysorrhoea,  1,. 
a  ilalc.     b  Female,     c  Caterpillar,     d  Pupa. 


Generation  annual.  This  insect  is  common,  but  rarely 
appears  in  great  numbers.  In  the  Berlin  Zoological  Garden 
they  destroy  the  foliage  almost  every  year.  It  is  less  common 
in  Britain  than  the  closely  allied  B.  slmilis,  Fiiss.  (aurijiua, 
Fabr.) ;  an  insect  of  similar  appearance,  but  with  the  abdo- 
minal tuft  of  down  golden-yellow.  It  resembles  B.  chry- 
sorrhoea in  habits,  and  especially  attacks  hedgerows  -and 
orchard  trees. 

r.  Relations  la  the  Forest. 
The  insect  is  polyphagous ;  the  caterpillars  are  found  on 
pear  and  plum  trees,  on  oak,  white-thorn,  and  also  on  beech, 
elm, maple,  hornbeam,  willows,  poplars,  roses;  even  on  robinia 
when  nothing  else  offers. 


310  PKOTKCTION    AOAINST   INSECTS. 

The  caterpillars,  enclosed  in  their  common  web-nest,  first 
gnaw  the  upper  side  of  the  leaves.  Next  spring,  after 
renewing  their  nests,  they  feed  on  the  buds  and  young  leaves, 
and  later,  on  the  blossoms  and  fully  developed  leaves,  except 
the  petiole.  In  this  way,  the  fruit  is  considerably  reduced  in 
quantity,  if  not  entirely  destroyed.  Up  to  tlie  middle  of  May, 
in  bad  weather  and  also  during  the  night,  they  retire  to  their 
nests.  After  the  third  moulting,  at  the  middle  or  end  of  May, 
they  abandon  their  nests,  and  wander  among  the  trees  to 
feed. 

The  crowns  of  the  trees  which  are  attacked  begin  about  the 
end  of  August  to  look  as  if  they  had  been  singed  by  fire  ; 
later,  the  woods  become  more  or  less  completely  defoliated. 
If  defoliation  takes  place  before  Midsummer  a  second  foliage 
may  appear. 

d.  Profectivp  RuUfi. 

Protection  of  enemies.  Titmice  and  the  cuckoo  are  very 
useful. 

Cutting  off  the  caterpillar  nests  with  shears,  and  burning 
them. 

Collecting  and  killing  the  caterpillars  in  May,  and  the  pupae 
in  June.  Care  must  be  taken  to  protect  the  hands  against  the 
hairs,  which  cause  inflammation.  The  above  measures  should 
be  adopted  for  orchard  and  avenue  trees. 

5.  Lijxiris  monacha,  L.  {BlacJi  Arches,  or  Nun  Moth), 
a.  Description. 

The  moth  has  a  spread  of  wings  of  40  mm.  ( J  ),  up  to  50 mm. 
(?).  Fore-wings  white,  with  many  ])lack  zigzag  transverse 
lines  and  patches,  hind-wings  light  grey  ;  abdomen  with  broad, 
rose-red  bands,  separated  by  black  bands,  which  are  very  well 
marked  in  the  ?  . 

The  caterpillar  is  40  to  50  mm.  long,  with  10  legs,  haii-y, 
tapering  slightly  towards  the  tail,  reddish-grey  above  and 
greenish-grey  below  ;  with  G  bluish  warts  bearing  tufts  of  long 
hairs  on  each  segment,  and  on  the  Gth  a  velvety-black  heart- 
shaped  spot. 


LIPARIS    MOXACHA. 


311 


The  jJ^ipfi  is  at  first  greenish,  later  dark  brown,  with  a  bronze 
lustre,  and  covered  with  shaggy  hairs. 


h.  Life-Jiistory. 
The  moth  appears  in  July  and  at  the  beginning  of  August, 
and  may  exceptionally  be  found  till  the  end  of  September. 


(D  ® 


Fig.  157. — Liparis  monacha,  L. 
a  Imago{?).     b  Eggs  (enlarged),     c  Caterpillar,     d  Pup 


Both  sexes  usually  sit  at  daytime  on  the  stems  at  a  moderate 
height  from  the  ground. 

In  the  month  of  August  the  ?  lays  about  150  eggs  of  a 
reddish-bronze  colour  in  groups  of  from  5  to  50  in  bark-cracks, 
or  among  the  moss  and  lichen  of  large  poles  and  tree  stems, 
of  Scots  pine  or  spruce,  usually  at  10  feet  from  the  ground. 
When  the  insect  swarms,  spruce  boles  are  covered  with  eggs 


312  PROTECTfON    AGAINST    INSECTS. 

up  to  the  top,  but  in  Scots  pine,  only  as  far  as  the  rough  bark 
extends.  Later  the  eggs  become  of  a  pearly  grey  colour,  and 
hibernate  without  any  protective  covering. 

The  caterpillars  hatch  at  the  end  of  April,  or  the  beginning 
of  May.  They  remain  for  a  few  days  (2  to  6)  in  small  groups 
near  their  hatching  place,  and  then  ascend  to  the  crowns  of 
the  trees.  Until  they  are  half-grown,  they  are  able  to  let 
themselves  up  and  down  by  threads  should  they  be  disturbed. 
They  become  full  grown  by  the  end  of  June,  or  the  beginning 
of  July.  When  young,  they  are  rather  sensitive  to  changes  of 
weather,  and  are  easily  blown  down  by  the  wind,  and  may  then 
fall  on  to  young  forest  growth. 

Pupation  takes  place  at  the  end  of  June  or  the  beginning  of 
July,  and  the  pupae  may  be  found  fixed  by  a  few  threads  in 
bark-cracks  low  down  on  the  stems,  also  on  needles  of  low 
branches,  and  even  on  undergrowth. 

The  moth  emerges  in  15  to  20  days  after  pupation,  the  active 
J  appearing  a  few  days  before  the  $  . 

Generation  annual.  The  insect  appears  sometimes  in  truly 
formidable  numbers.  The  moths,  especially  the  3  ,  are  very 
active,  and  may  fly  for  long  distances  in  swarms,  but  usually 
remain  localised. 

L.  monacha  is  tolerably  common  in  many  localities  in 
Britain,  chiefly  in  the  south  of  England,  but  is  not  generally 
regarded  as  an  abundant  insect.  It  is  rare  in  conifer  woods 
and,  consequently,  seldom  if  ever  destructive;  its  usual  food- 
plant  appears  to  be  the  oak.  Indeed  most  British  lepidopterists 
seem  to  be  unaware  that  it  is  a  conifer  feeder. 


c.  Relations  to  ilie  Forest. 

This  species  attacks  all  conifers,  but  prefers  the  Scots  pine 
and  spruce,  and  tall  poles  and  old  trees  of  these  species  to 
younger  ones ;  it  also,  however,  attacks  young  growth  and  also 
broadleaved  trees,  such  as  beech, hornbeam,  birch,  oak,  orchard 
trees,  least  of  all  the  ash  and  alder.  In  cases  of  scarcity  of 
other  food,  it  will  not  disdain  low  shrubs. 

The  caterpillars  devour  the  needles  and  buds.  When  young 
they  bore  into  the  tender  shoots,  causing  them  to  wilt;  the 


L1PARI8    MONACHA. 


313 


older  larvae  attack  the  fully  formed  needles,  and  in  the  case  of 
spruce,  eat  them  from  the  apex  downwards.  They  feed  on 
Scots  pine  in  a  most  wasteful  manner,  hiting  off  the  tops  of 
the  needles  and  letting  them  fall  to  the  ground,  and  only 
eating   their   lower  portions.      The   quantities  of   half-eaten 


I 


'    J861 


Fig.  158. — Shoot  with  a  lateral  branch—         Fig.  lo9. — Leading  shoot  (lopped)— 
of  a  spruce  fir  which  had  been  stripped  by  Liparis  motiaeha,  L. 

Date  of  injury,  1856  :  production  of  short  growth,  1857  ;  of  bristle-needles,  1858  ; 
of  short  growth,  1859;  of  nearly  normal  growth,  1860;  of  normal  growth  with 
lateral  dormant  buds,  18G1. 


needles   lying   on    the   ground   then  hetray  the  presence  of 
the  enemy. 

In  high  coniferous  wood  the  older  needles  are  preferred  to 
the  younger,  and  the  attack  spreads  downwards  and  outwards 
from  the  summits  of  the  trees.  Among  young  growth,  on  the 
contrary,  the  young  shoots  are  eaten  first.     If  the  attack  is 


314 


I'ROTECTION    AGAINST   INSECTS. 


extensive,  and  towards  its  end,  the  caterpillars  return  in  swarms 
to  the  summit  of  the  trees  and  eat  oil"  all  the  j'ounger  shoots. 
Repeated  observation  has  proved  that  these  caterpillars  are  all 
sickly  and  eventually  die,  and  inside  them  a  great  variety  of 
parasites  is  found. 

The  attack  lasts  from  May  till  July,  and  is  repeated  for  about 
3  5'ears.  In  the  2nd  or  3rd  year  it  culminates,  and  complete 
defoliation  may  kill  the  whole  wood.  The  spruce  is  more  sensi- 
tive to  the  attack  than  the 
Scots  pine.  The  latter 
may  recover  the  loss  of  half 
its  foliage. 

The  process  of  recovery 
in  the  spruce  is  shown  in 
Figs.  158,  159,  which 
represent  portions  of  trees 
attacked  in  Silesia  during 
1855  and  185G.  The  length 
of  the  internodes  was  least 
in  1858,  the  normal  growth 
not  being  resumed  till 
1861,  and  a  characteristic 
growth  of  stunted  "  bristle- 
needles"  appeared,  a  fea- 
ture which  not  unfrequently 
ifn     -D    ui   f     i     1         i     -11        occurs  in  the  case  of  Scots 

160. — Beech  leaf  eaten  by  a  caterpillar         ^  ►jv^v^uo 

of  L.  monacha,  L.  pine. 

The  insect  is  found  both 
in  the  plains  and  in  hilly  country.  The  most  severe  attack 
by  the  "  Nun "  during  the  present  century  was  during 
1853-1858  in  East  Prussia,  Lithuania,  and  Poland ;  in 
1858  a  bark-beetle  attack  followed,  and  the  calamity  only 
stopped  in  1860.  From  the  29th  July,  1853,  to  the 
27th  June,  1855,  in  the  Pothebude  Forest,  where  the 
attack  commenced,  6,375  acres  of  forest  were  completely 
stripped  of  needles,  and  about  half  as  much  more  nearly 
stripped.  The  larval  droppings  covered  the  ground  to  a  depth 
of  5  to  8  cm.,  in  many  places  to  15  cm.,  and  kept  falling  to 
the  ground  with  a  sound  like  heavy  rain.      Up  to  the  1st 


LIPARIS    MONACHA.  315 

October,  1862,  31,300,000  cub.  feet  of  ^YOod  were  killed, 
30,823,000  cub.  feet  by  the  Nun,  and  437,000  cub.  feet 
by  bark-beetles.  The  ravaged  area  exceeded  21,000  acres,  and 
in  East  Prussia,  between  1853  and  1863,  over  467,000,000  cub. 
feet  of  wood  had  to  be  felled,  while  267,000  acres  were 
devastated. 

The  damage  done  in  the  neighbouring  Prussian  province  was 
still  greater,  and  it  has  been  computed  that  by  the  Nun  and 
bark-beetles  6,400  geographical  sq.  miles  of  forest  in  Piussia, 
and  in  Prussia  600  sq.  miles,  altogether  7,000  sq.  miles  of 
forest,  were  destroyed,  and  at  least  6,427,500,000  cub.  feet  of 
timber  killed.  It  was  noted  as  a  curiosity  that  the  manuring 
of  the  forest  soil  by  the  dung  of  the  caterpillars,  and  the 
oi:)ening-out  of  the  woods,  produced  such 
a  heavy  growth  of  grass  that  the  stags,  ^^ 

owing  to  the  greater  abundance  of 
provender,  bore  antlers  of  unusual  size. 

In  1889  and  1890  this  insect  proved  '. 

very  destructive   in   Bavaria,  south   of  "-? 

the  Danube,  the  expenses  of  the  cam- 
paign against  it  amounting  to  as  much 
as  .i'100,000.  ^'--    i^J-  7  ^'"'^^  \f 

eaten  by  the  caterpillar 

In  attackmg  broadleaved   trees,   the        of  z.  »iome/ia,  L. 
caterpillars  frequently  eat  the  base  of 
the  leaves,  letting  the  remaining  portion  fall  to  the  ground : 
this  is  the  case  with  birch  and  aspen,  whilst  with  beech  and 
oak  only  a  portion  of  the  leaf  is  eaten,  the  leaf-stalk  being 
usually  untouched  (Fig.  160). 

The  attack  is  never  fatal  to  broadleaved  trees. 

(L  Prolcrlive  Rules. 

i.  Avoidance  of  pure  spruce  or  Scots  jnnc  woods  and  introduc- 
tion of  suitable  species,  especially  beech,  in  intermixture  with 
such  woods. 

ii.  Thinning. — By  careful  thinning  future  remedial  measures 
are  facilitated,  and  a  better  control  over  the  collectors  of  eggs, 
larvae  or  pupae  is  maintained. 

iii.  Protection  of  enemies :  bats,  cuckoos,  woodpeckers,  crows, 
starlings,  titmice,  golden-crested  wren,  etc.     The  two  latter 


316  PROTECTION   AGAINST   INSECTS. 

are  extremely  useful  in  destroying  the  eggs  throughout  the 
winter.  The  ground-beetles,  Carahus  filahratas,  L.,  and  Calo- 
soma  sycophanta,  L.,  are  also  very  useful  on  the  Continent,  the 
larvae  of  the  latter  attacking  the  moths'  eggs,  and  the  beetles 


Fig.  1G2. — Spruce  leaikr,  with  iiUectcJ  (a7«y7;//)  larvae  of  tlio  Nun  moth. 

the  caterpillars.  Many  ichneumon-wasps  and  Tachinae  attack 
the  caterpillars,  for  instance,  Tarldna  monachac,  liatz.,  T. 
j)halaenarum,  L.,  etc. 

In  1892  J.  Gold  found  that  in  N.  E.  Bohemia  59  per  cent,  of 
the  caterpillars  were  attacked  by  Tachinae  and  11  per  cent,  by 


LIPARLS    MONACHA.  317 

ichneumon  wasps.  Finall}',  towards  the  end  of  the  last 
great  swarm  of  the  Nun  moth  in  Bavaria,  1890,  fungi, 
especially  bacteria,  were  destroj'ing  the  caterpillars,  the  latter 
became  sleepy,  and  hung  Ijent  like  horseshoes  on  the  twigs,  or 
in  masses  at  the  tops  of  the  trees.  If  such  caterpillars  are 
squeezed,  a  brown  stinking  liquid  exudes,  whilst  healthy 
caterpillars  exude  green  liquid. 

e.  Remedial  Measures. 

i.  Collection,  and  destruction  of  the  eggs  by  fire,  from  autumn 
till  the  middle  of  April.  The  piece  of  bark  on  which  the  eggs 
are  laid  is  removed,  and  the  eggs  scraped  off  with  a  knife  into 
a  bag  furnished  with  a  wooden  funnel-shaped  mouth.  The 
stems  are  cleared  up  to  16  feet  high,  preferably  by  day- 
labourers,  at  first  on  foot  and  then  with  a  ladder,  and  the 
woods  in  which  many  moths  have  been  observed  should  be 
first  treated.  This  treatment  is  easier  in  smooth-barked  pole- 
woods  of  spruce  than  in  older  woods  with  rough  bark. 

One  gramme-weight  of  eggs  contains  about  1,200,  and  the 
cost  of  collection  is  about  dd.  to  Is.  for  15  grms.  In  the  winter 
of  1839-40,  in  the  Biesenthal  forests  near  Eberswald,  10  tons 
of  eggs  were  collected.  The  eggs  should  be  burned  in  small 
lots,  as  otherwise  they  explode  like  gunpowder. 

ii.  Killing  the  clusters  of  newly-hatched  caterpillars  in  April 
and  May  by  means  of  cloths,  brushes,  or  by  rubbing  them 
with  moss,  sods,  etc.  Great  care  must  be  taken  to  seize  the 
proper  moment  for  this  operation,  and  a  delay  of  only  a  few 
days  may  prevent  its  being  done.  The  cloths,  etc.,  used  may 
be  soaked  in  tar  to  render  their  action  more  efiicacious.  This 
operation  is  also  best  done  by  daily  labour,  but  under  careful 
supervision,  one  overseer  being  appointed  for  every  20  to  30 
■workmen.  One  man  should  be  able  to  work  over  6  to  8  acres 
per  diem,  and  the  most  suitable  place  to  work  in  is  among 
young  poles,  where  the  caterpillars  can  be  readily  seen,  and 
are  not  too  high  up  the  stems. 

iii.  Collection  of  rater2)illars  and  pupae,  commencing  in  June. 
Small  caterpillars  are  usually  collected  in  young  growth,  on  to 
which  they  have  been  blown  ;  later  on,  when  they  have  ceased 


31 S  PROTECTION    AGAINST   INSECTS. 

spinning,  they  are  shaken  down  from  the  poles.    It  is  preferable 
to  collect  the  pupae. 

iv.  ( 'oUection  of  2  moths  from  the  beginning  of  July.  This 
should  be  done  as  soon  as  they  emerge,  and  in  the  earliest 
hours  of  the  morning;  it  gives  the  best  results  during  cool 
weather.  A  cloth  may  be  covered  with  adhesive  matter,  and 
used  to  daub  the  insects. 

It  is  not  yet  fully  decided  whether  this  measure  is  very 
effective  or  not,  some  authorities,  such  as  Altum,  ranking  it  as 
the  best  to  be  adopted,  and  others,  as  llatzeburg,  considering 
it  as  almost  useless. 

In  the  forests  near  Ebersdorf  in  Ileuss-Greiz,  between  the 
26th  June  and  the  12th  August,  1868,  600,000  ?  were  destroyed 
at  a  cost  of  iJ270. 

v.  Trenches  are  usually  of  little  use.  Smearing  the  stems 
in  winter  from  the  ground  up  to  the  large  branches  with  a 
mixture  of  lime  (^  bushel),  soft  soap  (3  lb.),  potash  (^  lb.),  clay 
and  cow-dung  destroys  the  eggs.  This  method  can  be  used 
for  orchard  trees  only. 

vi.  Tlie  application  of  liigh  grease-hands  about  2  in.  wide  at 
a  height  of  16  ^to  20  ft.  from  the  ground,  above  the  places 
where  eggs  are  laid.  This  should  be  done  at  the  end  of  March 
or  April,  and  the  bark  here  is  sufficiently  smooth,  and  requires 
no  preliminary  scraping.  The  rings  are  smeared  by  means  of 
a  broad  brush  fastened  at  right  angles  to  a  long  pole.  This 
has  in  many  cases  proved  an  excellent  remedy.  The  little 
caterpillars  remain  sitting  in  thousands  below  the  rings,  w'hich 
cut  off  their  way  to  the  crowns  of  the  trees.  The  composition 
used  should  retain  its  fluidity  for  some  time,  but  need  not  be 
very  sticky,  as  the  caterpillars  to  be  caught  are  so  small. 

Large  lires  lighted  at  night  in  the  forest  to  attract  and  burn 
the  moths  have  failed  to  do  any  good.  In  1890,  in  the  Bavarian 
forests  the  moths  were  attracted  by  electric  lights  to  the  mouth 
of  a  large  funnel  into  which  they  were  sucked  by  an  exhaust 
current  of  air  produced  by  steam  power.  Large  numbers 
were  collected  by  this  method,  and  killed,  but  it  cannot  be 
stated  whether  the  utility  of  this  proceeding  is  commensurate 
with  its  expense. 

Low  grease  hands,  as  already  described,  page  300,  for  the 


NOCTUIDAE.  319 

pine-moth,  are  also  useful,  as  many  nun  caterpillars  spin 
themselves  down  or  crawl  down  to  the  ground.  They  have 
such  an  objection  to  the  grease  bands  that  they  sit  below  them 
by  thousands  and  die  of  starvation. 

The  collection  of  eggs,  caterpillars,  and  pupae  gives  good 
results  only  at  the  beginning  of  an  attack.  When  the  insect 
appears  in  swarms,  the  collection  of  moths  and  the  use  of 
low  grease  bands  are  the  most  effective  measures.  High  grease 
bands  cost  too  much.  In  the  case  of  low  grease  bands,  the 
undergrowth  must  be  cut  and  burned,  the  areas  attacked 
should  be  isolated  by  a  sutficiently  broad  grease  barrier,  and 
so  should  intact  areas. 

Although  the  Scots  pine  is  usually  first  attacked,  it  does  not 
suffer  so  much  as  the  spruce,  as  the  stem  of  the  latter  bears 
eggs  up  to  the  top  and  the  young  caterpillars  begin  by  eating 
the  yearling  needles.  In  the  Scots  pine  they  commence  lower 
down  with  the  old  needles.  The  Scots  pine  is  not  therefore 
killed,  as  long  as  the  year's  needles  are  spared,  while  the 
spruce  dies  if  80  per  cent,  of  the  needles  are  eaten. 

Liparis  dispar,  L.,  the  gypsey  moth,  which  in  Europe  attacks 
all  broadleaved  trees,  was  introduced  into  Massachusetts  by  a 
person  who  wished  to  interbreed  it  with  a  silk-moth.  This 
pest  increased  in  numbers  over  850  sq.  miles,  and  became  so 
destructive  to  trees  and  crops  that  the  State  had  to  organise 
measures  for  its  extermination  on  an  immense  and  expensive 
scale,  375,000  dollars  being  spent  in  1890—1894. 

Family  IV. — Noctuidae  (Night  Moths). 
Deacription  of  Famihj. 
Moths  with  long,  setaceous  antennae,  usually  covered  with 
fine  hairs,  and  sometimes  pectinate  in  3  ;  ocelli  present; 
proboscis  long  ;  wings  narrow,  during  repose  roof-like  or  level ; 
frenulum  present.  The  markings  of  the  fore- wings  are  usually 
characteristic  and  take  the  form  of  three  or  four  transverse 
lines  of  which  the  second  from  the  outer  margin  is  elbowed, 
and  of  three  spots ;  two  are  situated  near  the  anterior  margin, 
the  outer  being  kidney-shaped  {renifonn  stigma),  the  inner 
circular    {orbicular   stigma) ;    the    third    is    elongate,    and   is 


320 


PROTECTION   AOAINST    INSECTS. 


beneath  the  orbicular  spot  {daviform  stir/ma).  These  mark- 
mgs  are  constant  in  position,  but  some  or  all  of  them  may  be 
absent.  The  body  is  thick,  and  usually  covered  with  down ; 
the  head  surrounded  by  a  collar.  Flight  nocturnal  or  during 
twilight,  hardly  ever  by  day. 

CaterpiUars  usually  bare,  rarely  hairy,  commonly  with  10 
prolegs,  sometimes  with  8  or  6. 

Pupation  of  the  bare  caterpillars  generally  takes  place  in  the 
ground,  in  a  cocoon  made  of  grains  of  sand  bound  together  by 
a  few  threads.  The  hairy  caterpillars  spin  a  cocoon  alcove 
ground.  Pupae  usually  slim,  spindle-shaped  and  dark  coloured. 
Many  of  the  caterpillars  live  on  woody  plants,  eating  needles 
and  leaves,  but  the  majority  of  them  feed  on  grasses  and  low 
plants.     A  few  species  are  highly  injurious  to  forests. 


Fig.  HJd.—Xocli/d  piiiipcrda,  Tan/.     {Nulnral  nizc  :  iig.  r  ciiliii-god.) 
a  Male,     b  Female,     c  Eggs  on  a  pine-needle,     d  Caterpillar,     c  I'upa 


1.  Noctiia  pinipcrda,  Panz.  {Vine  Beauty,  or  Phie  A^octua). 
a.  Desrriplion. 

Moth  with  a  wing-expanse  of  35  mm. ;  fore-wings  russet-red 
marbled  with  grey  ;  orbicular  and  reniform  stigmata  yellowish- 
white,  conjoined,  the  latter  large,  oblique  and  produced  towards 
the  tip  of  the  wing ;  hind-wings  and  abdomen  greyish-brown. 

Caterpillar  40  mm.  long,  with  1()  legs,  almost  hairless,  of  a 
yellowish-green,  with  3  or  5  whitish-coloured  stripes  and  a 
light-brown  head. 


NOCTUA    PINIPERDA.  321 

Pi(2)a  somewhat  elongate,  of  a  bright  brown  colour,  with  two 
spines  on  its  tail. 

b.  Life-hisfory. 

The  moth  appears  from  the  end  of  March  to  the  beginning 
of  May. 

The  2  laj's  30  to  70  round,  dull-green  eggs  on  the  needles  of 
old  Scots  pines. 

The  caterpillars  hatch  out  in  May,  spin  freely  when  young, 
and  are  fully  grown  by  the  middle  of  July. 

Pupation  takes  place  at  the  end  of  July  or  beginning  of 
August,  under  moss,  dead  leaves,  on  or  in  loose  earth,  usually 
under  the  cover  of  the  tree  on  which  the  insect  feeds.  The 
pupse  are  sometimes  found  in  colonies,  in  the  holes  whence 
stumps,  etc.,  have  been  extracted. 

Generation  annual.  The  caterpillar  sometimes  appears  in 
enormous  numbers,  but  is  susceptible  to  changes  of  the 
weather.  It  is  tolerably  common  in  pine  woods  throughout 
Great  Britain. 

c.  Relations  to  the  Forest. 

The  caterpillar  attacks  chiefly  the  Scots  pine,  especially 
when  20  to  40  years  old,  but  in  case  of  necessity  it  may  feed 
on  older  trees  and  other  conifers,  such  as  spruce,  Weymouth 
pine  and  juniper. 

When  young  the  caterpillar,  according  to  Eatzeburg,  bores 
into  the  bud-sheaths  of  the  spring  shoots,  which  thus  become 
brown,  wilt  and  die.  Later  on  the  needles  are  attacked, 
beginning  with  their  edges,  and  finally  they  are  entirely 
devoured,  usually  on  the  lower  branches,  but  also  higli  up  in 
the  crown.  The  attack  lasts  from  May  till  July,  but  is  not  so 
destructive  as  that  of  Gastropacha  yini,  L.,  as  the  Scots  pines, 
even  if  extensively  stripped  by  it,  usually  form  new  buds  and 
recover.  One  should  therefore  await  results  before  felling 
woods  that  have  been  completely  stripped  of  needles.  Only 
when  the  fatal  rosettes  of  needles  (Fig.  143)  appear  is  the 
death  of  the  trees  imminent.  The  insect  inhabits  hilly 
regions,  and  is  most  common  in  forests  where  the  soil  has 
become  impoverished  by  removal  of  litter, 

F.P.  Y 


322  PROTECTION    AGAINST   INSECTS. 

(1.  Froiective  Rtileii. 

Mix  broadleaved  trees  with  Scots  pine. 

Protection  of  enemies:  Fox,  badger,  hedgehog,  shrew,  cuckoo, 
crow,  starHng,  thrush,  titmice,  golden-crested  wren,  etc. 
Calosoina  sijcophanta,  L.,  is  very  useful  on  the  Continent,  and 
many  parasitic  insects  and  fungi  attack  the  larvae. 

Fungi  {Empiisa  sp.)  killed  nearly  all  the  caterpillars  in  the 
Tuchler  Haide  in  1867,  their  bodies  being  covered  with 
yellowish-grey  sporangia,  which  after  rain  became  dark  l>rown. 
The  infected  caterpillars  were  brittle  like  the  pith  of  elder,  and 
filled  internally  with  a  yellowish  substance. 


e.  Remedial  Measures. 

i.  Pigs  may  be  admitted  to  the  woods  from  July  till  hard 
frost  sets  in.  In  the  forest  district  of  Cloppenburg  in  Olden- 
burg in  1845,  58  pigs  in  29  days  (Noveml>er  and  December) 
are  estimated  to  have  destroyed  16,000,000  pupae. 

ii.  Caterpillars  may  be  collected  from  the  middle  of  May 
onwards  by  beating  the  stems,  or  in  July  by  picking  them 
from  lower  growth,  or  at  the  foot  of  the  stripped  trees,  where 
they  often  collect  in  numbers. 

iii.  Pupae  may  be  collected  during  the  winter,  under  moss, 
etc. ;  the  holes  whence  stumps  have  been  extracted  should  l)e 
speciall}'  examined. 

iv.  Moths  may  be  collected  by  striking  the  trees  in  cloudy 
weather  or  by  "  sugaring." 

Trenches  are  not  of  much  use,  as  the  caterpillars  are  Httle 
given  to  wandering  about. 


2.  Xoctiia  (Ar/rotis)  vcsti(jiaUs,*  Pott. 

a.   Descriplion. 

Moth  with  an  expanse  of  wing  of  30  to  35  mm.  Fore-wings 
ashy  grey,  mingled  with  brown,  variable  in  depth  of  colour, 
with  fine  black  veins,  the  three  stigmata  conspicuous,  darker 

•  Larvae  of  the  different  species  of  Agroth  usually  live  in  the  ground;  tliey 
gnaw  through  plants  above  the  roots,  and  in  America  are  appropriately  termed 
cut-woriuK, 


NOCTUA    VESTIGIALLS.  323 

than  the  ground,  the  orl)icular  and  reniform  with  light  borders, 
the  former  sometimes  reduced  to  a  point.  Hind-wings  light 
grey  with  darker  borders. 

Caterpillar  35  mm.  long,  with  16  legs,  of  a  dull  brownish 
grey;  head  with  a  triangular  frontal  snot,  and  another  on  the 
vertex,  meeting  at  their  apex,  their  borders  forming  a  X . 

Pupa  brown,  terminated  by  two  very  short  points. 

I),   Life -1ml or  11 . 

The  moth  appears  from  the  middle  of  August  till  the  middle 
of  September. 

The  eggs  are  laid  on  the  ground  amongst  the  grass  and 
herbage. 

The  caterpillars  hatch  in  September,  and  hibernate  in  the 


Fig.  1G4. — Xocliia  vcsligiatis,  Kott.     {Xatio-al  sizeJ) 

soil  when  half-grown;  as  they  are  earth-coloured  it  requires 
an  accustomed  eye  to  detect  them. 

Pupation  takes  place  from  the  end  of  June  till  August,  either 
in  the  ground,  in  a  cocoon,  or  exceptionally  among  the  needles 
of  young  Scots  pine. 

Generation  annual. 

The  cater})illar  dislikes  the  light,  and  during  the  day  remains 
in  the  ground  or  concealed  under  the  leaves  of  the  plants  on 
which  it  feeds. 

c.  Relalions  to  IJir  Forest. 
The  caterpillars  of  most  species  of  Xoctiia  are  termed 
"surface  caterpillars,"  and  those  of  the  present  species  chiefly 
feed  on  agricultural  crops,  young  shoots  of  grasses,  potatoes, 
turnips,  etc.,  towards  harvest  time.  It  also  attacks  the  Scots 
pine  and  the  larch  as  seedlhigs  in  their  first  and  second  years, 

y2 


324  PROTECTION    AGAINST    INSECTS. 

and  exceptionally  the  seedlings  of  broadleaved  trees.  The 
little  one-year-old  seedlings  are  usually  bitten  off  by  it  in 
April  and  May  close  to  the  coUum,  never  deeper  than  1  in. 
under  ground.  The  larva  then  feeds  on  the  root,  the  lower 
part  of  the  stem,  and  lastl}'  on  the  needles.  In  June,  when 
the  plants  are  somewhat  older,  they  are  bitten  off  at  about 
the  middle  of  their  height,  and  the  stem  and  roots  gnawed. 

Two-year-old  seedlings  usually  have  their  weaker  side 
shoots  bitten  off,  more  rarely  the  leading  shoot  as  well,  and 
some  of  the  needles  are  eaten ;  the  bark  may  also  be  gnawed, 
but  such  plants  commonly  recover  from  the  injury  they  have 
received. 

The  damage  is  iigually  done  at  night,  when  the  caterpillars 
crawl  along  the  surface  of  the  ground  from  one  plant  to 
another ;    during  the  day-time  they  proceed  under  ground. 

Poor  sandy  soil  in  plain  districts  is  most  frequented  by  this 
pest. 

This  insect  has  recently  become  very  injurious  in  North  and 
North-east  Germany.  It  is  tolerably  common  on  the  coasts 
of  the  British  Isles,  but  is  rarely  met  with  inland,  and  has 
attracted  little  or  no  attention  as  an  injurious  species. 

d.  Profective  Rules. 

i.  Areas  both  in  nurseries  and  in  the  forest  which  are  to  be 
sown  up  should  be  thoroughly  weeded  in  the  previous  year,  as 
the  $  will  not  lay  her  eggs  except  among  grass  and  herbage. 

ii.  For  planting-out,  not  seedlings  of  the  first  year,  but  2-  to 
3-  year-old  plants  with  balls  of  earth  should  be  emploj-ed,  as 
the  caterpillars  find  it  difticult  to  bore  tlirougli  the  firm  earth 
of  the  balls. 

iii.  Trolection  of  enemies. 

e.  Remedial  Measures. 

■Pigs  may  be  driven  into  [ilaces  where  this  pest  has  appeared. 

The  ground  may  bo  ploughed  up  or  trenched  with  hoe  or 

spade,  and  the  caterpillars  collected  and  destroyed.     In  quite 

loose   sand    the   plants   may  be    lifted  by   hand,   and   those 

uninjured  or  slightly  injured  replanted. 


NOCTU A    S  EO  ET  UM . 


825 


The  caterpillars  may  be  poisoned  by  laying  baits  of  cabbage 
or  lettuce-leaves  sprinkled  with  arsenic  along  the  beds. 
The  moths  may  be  caught  by  "  sugaring,"  and  destroyed. 

3.  Noctna  (Agrotis)  segetuin,  Schiff.  {TiiDiip  Dart-Moth), 
a.  Description. 

Muth  with  a  wing-expanse  of  40  mm. ;  fore-wings  yellowish- 
grey  or  yellowish-brown,  with  darker  marks,  stigmata  of  the 
same  ground-colour  as  the  wings,  the  reniform  and  orbicular 
margined  with  black  ;  hind-wings  milky-white,  with  no  lunate 
spot. 

Caterpillar  50  mm.  long,  with  16  legs,  coloured  like  that  of 
a  ■  b 


3  ? 

Fig.  165. — Xoctua  segetum,  Scliiff.     {Xalural  size.) 

the  former  species,  but  with  the  triangular  spots  of  the  forehead 
and  vertex  separated  at  their  apices  by  a  space,  X- 
Pupa  light  brown,  with  two  long  anal  points. 

//.   Life-hislnry. 

The  moth  appears  from  the  end  of  May  till  the  middle  of 
June.  The  $  flies  a  few  days  later  than  the  <?  .  The  larval 
life  is  passed  in  the  ground,  the  caterpillars  hatching  out  in 
June  and  July,  and  pupating  in  April  and  May. 

Generation  annual.  Very  common  everywhere  in  Germany 
and  in  the  British  Isles.* 


c.  Relations  to  the  Forest. 
The  caterpillar  chiefly  attacks  the  roots  of  grasses,  cereals 
and  root-crops,  also  seedling  and  one-year-old  spruce  plants. 
In   some  Prussian  forest  districts  it  has  also  been  observed 

•    Vide  Miss  OrmertKl,  up.  cit.,  p.  -Ol. 


326  PROTKCTION    AGAINST    INSECTS. 

attacking  one-year-old  plants  of  Scots  pine  and  beech. 
Except  during  hard  weather  in  the  winter  its  attack  lasts  from 
August  to  April.  Seedlings  are  bitten  off  below  the  cotyledons, 
and  one-year-old  plants  gnawed  about  the  collum,  so  that  they 
frequently  die.  In  1864  this  insect  proved  very  destructive 
in  Silesia.  In  1880,  it  destroyed  spruce,  Scots  pine  and 
beech  near  Stralsund.  It  is  said  to  destroy  wheat  in  Russia. 
The  protective  measures  are  the  same  as  for  the  previous 
species. 

Family  V. — Geometridae  (Loopers). 
Description  of  Family. 

Antennae  of  the  imago  either  filiform  or  setaceous,  with  a 
thickened  basal  joint,  not  unfrequently  pectinate  in  3  ;  ocelli 
absent ;  proboscis  short ;  wings  large,  broad  and  delicate, 
usually  lying  more  or  less  level  in  repose,  sometimes  sloping  ; 
frenulum  always  present.  Bodies  slim,  resembling  those  of 
butterflies.  Flight  usually  at  dusk,  or  by  night ;  a  few  species 
fly  in  sunshine.  Caterpillars  bare,  or  only  slightly  hairy,  with 
10  (rarely  12)  feet;  they  move  about  by  loopin(i,  owing  to  the 
absence  of  the  first  3  or  2  pairs  of  sucker  feet ;  hence  their 
name,  loopers  or  span-icorms. 

Pupae  long,  with  a  short  pointed  tail,  bright  brown,  lying 
usually  without  cocoon  under  grass,  moss,  or  in  the  soil. 

The  caterpillars  feed  on  needles,  leaves,  buds,  etc.,  and  a  few 
species  are  injurious  to  forests. 

1.  (icoinciia  ])iiii(tii(i,  L.  {Ihtrdcrcd-irhilc  or  Viiir  LoojitT-Motli). 
a.  lipscriplidii. 
.!/(//// with  a  wing-expanse  of  35  mm.  3  bright  yellow,  with 
a  sharply-delined  area  at  the  tip  of  the  fore-wings  and  the 
margins  of  both  pairs  black-brown,  hind-wings  with  two  trans- 
verse dark  bands  ;  antennae  bipectinate.  ?  reddish-brown, 
the  tip  of  the  fore-wings,  borders,  and  1  or  2  transverse  bands 
on  both  wings  dark  brown  ;  antennae  setaceous.  In  both  sexes 
the  under-side  of  the  wings  is  brownish,  with  dark  lines  and 
numerous  spots,  and  a  broad  light-yellow  band  across  the 
middle  of  the  hinder  pair. 


GEOMETRA    PINIARIA.  827 

Caterpillar  35  mm.  long,  with  4  prolegs,  smooth,  yellowish 
green,  with  3  white  dorsal  stripes,  of  which  the  middle  one  is 
broadest,  and  two  broad  yellow  stripes  along  the  spiracles. 

Pupa  at  first  green,  later  bright  brown,  with  sharply-pointed 
tail. 

I>.  Life-hisfor//. 
The  moth  flies  in  May  and  June.     The  ^  is  fond  of  flying 
about  on  sunny  sultry  days  ;  its  flight  is  unsteady.     The   ?   is 
also  very  active.     When  resting,  the  moths  have  their  wings 
upright,  or  else  half-raised. 


.-ifes^ 


f 


Fig.  IGG. — G(oinelra2}iiiiaria,L.     {Natural  size.) 
a  Male,     b  Female,     c  Caterpillar,     d  Pupa. 

The  smooth,  somewhat  flattened  green  eggs  are  laid  in  a 
row  (2 — 12)  on  Scots  pine  needles  in  the  crowns  of  the  trees. 
The  caterpilhirs  hatch  out  at  the  end  of  Juno  or  the  beginning 
of  July,  and  are  fully  grown  by  October,  when  they  let  them- 
selves down  from  the  trees  by  threads.  If  the  weather  be 
mild,  caterpillars  may  even  be  found  in  December.  Pupation 
occurs  in  October  and  November  under  moss  or  other  soil- 
covering,  or  in  the  soil,  usually  under  the  cover  of  the  trees 
on  which  they  have  been  feeding, 

The  moth  emerges  in  May  or  June. 

Generation  annual.  Very  common,  and  widely  distributed 
in  pine  woods. 


8^8 


PROTECTION   Ar4AIN.ST   INSECTM. 


c.  ReJaiions  io  the  Forest. 
The   caterpillar   attacks   the   common   Scots    pine,    rarely 
other  pines,  the  spruce  or  silver  fir,  and  prefers  20-  to  40-  year- 
old  trees,  but  will  even  attack  trees  up  to  GO  years  of  age. 

The  needles  are  eaten  from  the  beginning  of  July  to  the 
end  of  October,  but  not  the  buds.  At  first  the  slioots  of  the 
current  year  are  spared,  but  later  on  they  are  also  attacked. 
The  young  caterpillars  gnaw  the  sides  of  the  needles  (Fig.  IGG) ; 
as  they  get  larger  they  eat  down  to  and  beyond  the  mid  rib. 
The  full  -  grown  larvae  cut  ofi"  the 
points  of  the  needles,  but  eat  the 
remainder  completely.  Complete 
defoliation  seldom  results  in  the 
death  of  the  trees,  as  the  attack 
commences  late  in  the  season,  and 
the  buds  well  provided  with  reserve 
material  produce  fresh  foliage  the 
ensuing  year.  Only  when  a  wood 
has  been  seriously  attacked  for  two 
successive  years,  the  second  attack 
destroying  most  of  the  needles,  do 
the  trees  die.  If,  however,  a  cold 
and  prolonged  winter  should  succeed 
a  somewhat  early  attack  of  the  pre- 
ceding year,  the  buds  may  become 
too  weakened  to  produce  useful 
needles  and  the  trees  may  die,  after 
one  attack  only.  As  long  as  tlie  cam- 
bium is  found  healthy  the  wood  may  be  saved.  It  is  there- 
fore unnecessary  to  commence  immediate  felling  of  defoliated 
woods,  as  after  an  attack  of  the  pine-moth.  Dense  woods  in 
sunny  aspects  of  warm  hill  districts  are  preferred  by  this 
moth,  and  windy  borders  of  the  woods  are  avoided. 


Fig.  167. — Scots  pine  needles 
attacked  by  G.  piniaria,  L. 


(t.  Protective  and  Remediat  Rutes. 
Mix  beech  with  conifers. 

Protection  of  enemies,  as  for  Trachea  2)iniperda. 
Admission  of  pigs  from  October  to  April  (50  pigs  to  500  acres). 


OEOMETRA    BRUM  ATA.  329 

Collection  of  pupae  in  winter. 

Collection  of  caterpillars  in  August  by  shaking  the  poles. 

Painting  rings  of  grease  or  lime-whiting  12  to  15  cm.  broad 
on  the  trees  at  Im.  from  the  ground.  This  costs  7s.  to  8.s*. 
per  acre  for  tar,  and  4.s".  to  Os.  for  lime,  and  has  proved 
effective. 

Raking  up  into  heaps,  and  burning  the  soil-covering.  This 
method  gave  excellent  results  over  about  190  acres  in  Pome- 
rania  in  1881-83  ;  about  ^  to  f  of  the  pupae  were  burned  with 
the  litter,  and  most  of  the  remaining  ones  being  exposed  by 
the  removal  of  the  soil -covering  were  eaten  by  birds.  Where 
the  soil-covering  had  been  left  intact,  the  moths  appeared  in 
the  following  spring  in  large  numbers.  The  ashes  must  be 
spread  over  the  ground.  In  dealing  with  the  attacks  of  this 
looper,  the  forester  should  continually  fell  sample  trees,  in 
order  to  become  acquainted  with  the  progress  and  condition  of 
the  insects,  the  appearance  of  parasites  and  the  degree  of 
resistance  offered  by  the  trees. 

The  extensive  Scots  pine  forests  near  Nuremberg,  weakened 
by  the  wholesale  removal  of  litter,  suffered  greatly  from  the 
pine  looper  in  1893-96,  about  125,000  acres  being  ravaged  of 
State,  communal,  and  private  forest.  Twelve  hundred  work- 
men were  engaged  at  4,s-.  a  day  to  work  up  the  dead  wood, 
04,000,000  cubic  feet. 

2.  Geometm   {Cheiinatohia)  hrumata,  L.  {]Vinte7--inot]i). 
a.  Description. 

Male  with  a  wing-expanse  of  25  to  30  mm.  ;  fore-wings 
ample,  grey-brown,  with  several  darker  transverse  wavy  lines; 
hind-wings  lighter,  with  a  faint  dark  waved  stripe  in  the 
middle.  Female  8  mm.  long,  of  a  brownish-grey,  wings  short 
and  aborted,  with  two  dark  bands  across  them,  antennae  and 
legs  long,  the  latter  strongly  developed. 

Caterpillar  16  mm.  long,  with  4  prolegs,  hairless,  at  Ih'st 
grey,  later  yellowish-green,  with  a  dark  dorsal  line,  and  3 
bright  longitudinal  lines  on  either  side. 

Pupa  11  mm.  long,  thickset,  yellowish-brown,  with  two  small 
outwardly-pointed  hooks  on  its  tail,  in  a  loose  cocoon. 


•"530  I'ROTKCTION   AfJAlNST    INSECTS. 

h.  Lifo-liislonj. 

The  moth  appears  from  October  to  December,  and  the  3 
flies  especially  at  evening-time. 

The  eggs  are  first  greenish,  and  later  on  reddish  ;  in  all 
200  to  300  are  laid,  either  separately  or  in  clusters  of  3  or 
more,  on  buds,  veins  of  leaves,  and  points  of  twigs  of  almost 
all  broadleaved  trees.  The  $  ascend  the  trees  usually  by  the 
east  and  north-east  sides,  which  are  protected  from  rain. 

The  caterpillars  hatcli  at  the  end  of  April  or  in  May,  are 
full  grown  by  the  middle  of  June,  and  in  July  let  themselves 
down  by  threads  from  the  crowns  of  the  trees  in  oi'dei-  to 


o 

9                            V2 
Vi 

a  Male. 

Fig.  \Qi?,.—Geomctm  hnimata,  L. 
h  Female.        c  Caterpillar. 

d  Pupa, 

pupate  ;  this  takes  place  at  the  bottom  of  the  trees  in  a  smooth 
hole  2  to  3  in.  deep  in  the  ground. 

Generation  annual.     Yery  widely  distributed  and  common, 
a  well-known  orchard  pest*  throughout  England. 

r.  nrJa/ions  to  Iho  Forrsf. 
The  caterpillar  attacks  several  broadleaved  trees,  especially 
orcliard  trees,  the  oak,  hornl)eam  and  lime;  to  the  former, 
especially  to  apple  and  pear  trees,  it  is  most  destructive,  the 
fruit-crop  being  weakened  or  destroyed.  When  young,  the 
caterpillar  bores  into  buds  through  the  side,  and  later  attacks 
blossoms  and  leaves,  as  well  as  the  green  shoots  and  young 
fruits.  It  continues  to  spin  during  these  attacks,  and  when 
disturbed  will  let  itself  down  and  climb  back  again  to  the  tree 
by  a  thread.     After  destroying  the  foliage  of  standards  over 

*    Vi</r  Miss  Ormciod,  o/>.  rU ..  ji.  :{3S. 


TORTRICID.^.  881 

coppice,  it  will  attack  the  underwood  up  to  the  middle  of 
June,  and  great  damage  is  thus  done  at  times. 

d.  Proleclive  Rules. 

Protect  enemies. 

Grease-bands  should  be  applied  to  the  trees  in  the  middle  of 
October  in  order  to  catch  the  ?  moths  on  their  way  up  the 
trunks.  The  trees  are  usually  encircled  with  paper  strips  4  in. 
broad,  bound  to  the  tree  by  string  above  and  below,  and  the 
tar  or  composition  is  painted  on  to  the  paper,  the  lower  part  of 
which  being  bent  upwards  to  prevent  the  composition  from 
trickling  down.*  These  bands  catch  many  other  insects  which 
are  destructive  to  orchard  trees,  such  as  the  apple-blossom 
weevil,  Antlionomus  pomorum,  L,,  and  the  codlin  moth, 
Carjweajjsa  jwrnonella,  L.  The  caterpillars  of  the  last  species 
creep  under  the  paper  to  pupate. 

The  practice  of  spraying  with  arsenical  washes  before 
flowering,  or  after  the  blossom  is  set,  is  a  valuable  method  of 
tre»tment. 

Other  species  of  Geometridae,  which  emerge  in  the  winter 
months,  and  the  females  of  which  are  apterous,  such  as 
Hibernia  defoliaria,  L.,  etc.,  may  be  dealt  with  when  injurious 
in  the  same  manner. 

The  pupae  may  be  destroyed  in  orchards  from  July  to 
September  by  trenching  the  ground  a  foot  deep  below  the 
trees,  and  stamping  it  firm. 

Family  VI. — Tortricidae  (Leaf-roller  Moths). 
Descrij)tio))  of  luiinihj. 

Moths  with  somewhat  short,  filiform,  or  bristle-like  antennae 
with  a  thick  basal  joint  ;  '2  ocelli.  Wings  rhomboidal,  the 
anterior  pair  usually  bright-coloured,  roof-shaped  in  repose; 
frenulum  present. 

Generation  usually  annual. 

Caterpillars  with  a  few  short  hairs  on  little  warts  ;  with  10 
prolegs  ;  usually  with  a  horny  shield  on  the  prothoracic  seg- 
ment and  a  horny  anal  flap.    Very  active,  and  strong  spinners. 

*  For  a  good  account  of  these  grease-bauds  and  nature  of  the  grease  to  be 
used,  see  Miss  Ormerod,  oj).  rif.,  p.  H42. 


332  PROTECTION    APxAlNST   INSECTS. 

Pupation  in  a  cocoon  either  above  or  in  the  ground.  Pup<p 
with  rows  of  spines  on  their  backs.  The  caterpillars  attack 
the  buds  or  shoots,  the  fruits  and  seeds,  or  the  needles  or 
leaves  of  broadleaved  or  coniferous  trees.  The  characteristic 
rolling  up  of  leaves  is  only  practised  on  broadleaved  species. 
Many  insects  injurious  to  forests  are  included  in  this  family. 


1.  1  [alias  chh>rana,  L.  {Green   Willow  Leaf-Roller). 

a.  DoKcripiion. 

Moth   with   wing   expansion    of   20   mm.  ;  fore-wings    and 

thorax  light  green,  the  former  with  a  whitish  anterior  border; 

head,  hind-wings  and  abdomen  white,  the  latter  sprinkled  with 

greenish-grey  scales. 

Caterpillar  15  mm.  long,  with  16  legs,  of  a  dirty  flesh-colour, 
with  a  dark  dorsal  stripe,  and  a  few  bristles.  Pupa  light 
brown,  with  rounded  head  and  smooth  hinder  extremity. 

b.  Life-hislortj,  etc 

The  eggs  are  laid  in  April  and  May  on  the  terminal  buds  of 
young  willows,  especially  on  Salix  riminalis,  L.  The  solitary 
caterpillar  hinders  the  development  of  these  buds  in  May, 
spinning  up  the  terminal  leaves  into  a  bundle  which  is  bent 
towards  one  side  of  the  shoot  in  which  it  lives  ;  it  feeds  from 
May  till  July,  not  only  on  the  leaves,  but  on  the  tender  young 
shoots  of  the  osiers.  The  lengthening  of  the  osiers  is  thus 
rendered  almost  impossible^  and  a  straggling  production  of 
side-shoots  results.  In  July  the  larvae  pupate  on  leaves  or 
shoots,  in  white  1)oat-shaped  cocoons.  The  moth  appears  14 
days  alter  pupation.  Neither  Pless  nor  Judeich  are  clear 
about  the  subsequent  life-history,  but  as  osiers  are  cut  down 
in  December,  there  is  probably  a  second  generation,  eggs  being 
laid  in  July,  pupation  in  September  and  the  pupae  hibernating 
near  the  ground. 

c.  Prolerlive  Rules. 

Cut  off  the  shoots  containing  the  caterpillars,  in  May  and 
June  and  again  in  August.  Each  bundle  contains  only  one 
larva,  which  should  be  killed. 


TORTRIX    VIRIDANA. 


3  88 


2.  Toftrix  viridana,  L.  {Oak  Leaf -roller) . 
a.  Description. 
Moth  with  wing-expansion  of  18  to  22  mm.  ;    fore-wings 
iiniforml}'  liglit  green,   and  hind-wings  Hght  grey;    whitish 
fringes  to  all  the  wings. 

Caterpillar  15  mm.  long,  with  10  prolegs,  at  first  greenish 
grey,  afterwards  dull  green,  with  head  and  anal  flap  hlack, 
with  warts  on  the  back.  Pupa  11  mm.  long,  slender  and 
black. 

h 

\ 


e 

f 


Fig.  169.— To><>iJ-  viridana,  L. 
a  Motli.      h  Caterpillar  suspended  by  a  thread,      c  Pupa. 


//.   Life-historij. 

The  moth  flies  during  daytime  at  the  end  of  June  and 
the  beginning  of  July.  The  eggs  are  laid  singly  or  in  little 
clusters  on  the  already  bitten  buds  of  the  oak,  and  pass  the 
winter  there.  The  cater[)illars  appear  in  April  and  May,  and,  as 
pupation  approaches,  spin  threads  by  which  they  let  themselves 
up  and  down  from  the  branches  ;  they  pupate  usually  at  the 
beginning  of  June,  on  the  twigs  of  the  trees  which  have 
been  attacked,  generally  in  the  upper  leaves,  which  they  roll 
together,  and  also  in  bark-cracks. 

Generation  annual.  Everywhere  tolerably  common,  and 
sometimes  present  in  enormous  numbers.  Very  destructive 
to  foliage  in  oak-forests  in  the  south  of  England. 


331 


PROTECTION   AGAINST   INSECTS. 


c.  Relations  to  fhe  Forest.    * 
The   oak  leaf-roller  moth   infests    oaks    only,   chiefly    the 
pedunculate  oak  because  it  shoots  before  the  sessile  oak,  and 


FiK.    170.^  Oiik  trees  slii|i|)C(l  of    foliaKO  in   Windsor    i-'orest    l)v    7'.   rirhlitiiii  ; 
beech  in  full  leaf.     I'hoto  by  W.  V.  Perree. 

chiefly  tall  poles  and  mature  trees.  The  attacks  of  the 
caterpillar  involve  the  buds,  leaves  and  inflorescence,  and 
spread  from   the   summit   of   the   crown    downwards.      The 


TORTRIX    BUOLIANA. 


335 


formation   of    foliage,    blossoms    and    acorns    for 
is   seriously   compromised,    and    sometimes    the 
completely  destroyed,  and  may  then  be  restored 
by  Lammas-shoots. 

In  coppice-with-standards  oak  standards  and 
underwood  only  are  attacked.  The  attacks  of 
this  moth  are  very  persistent,  having  lasted  for 
4  years,  in  the  Steigerwald  from  1869-72,  and 
in  Windsor  Forest  during  1890-91. 


the    year 
former    is 


(1.   Prntertivc  Jfeasures. 

Protection  of  enemies  :  starlings,  rooks,  jack- 
daws, etc.  Hardly  any  remedial  measures  can 
be  tried  in  forests.  The  caterpillars  of  the 
Dunbar  moth,  Cosniia  trapezina,  which  are  car- 
nivorous, are  useful  in  clearing  off  their  attack, 
as  well  as  that  of  the  winter  moth.  This  Noctuid 
moth  has  a  spread  of  wing  of  about  30  mm. ;  the 
fore-wings  are  variously  marked  with  pale  grey, 
rust-colour,  or  brown,  with  transverse  dark  and 
pale  lines,  the  hinder  wings  greyish  -  brown. 
The  $  lays  her  eggs  chiefly  on  oak.  The  cater- 
pillars are  pale  dull-green,  apple-green  beneatli, 
and  have  5  pale  whitish  or  yellowish  longi- 
tudinal stripes,  and  numerous  small  black  warts, 
each  surrounded  by  a  wbite  ring,  eight  to  a 
segment,  arranged  transversely  on  the  first  three 
segments  behind  the  head,  and  in  a  square  of 
four,  with  two  below  on  each  side  on  the 
succeeding  segments. 

Vimpla  scaiiica,  Grav.,  is  the  commonest  ichneumon-wasp 
that  attacks  the  oak  leaf-roller. 


V^ 


Fig.  171.  - 
O  a  k  - 1  e  a  {■ 
rolled  up  by 
the  cater- 
pillar of  the 
Oak-tortrix. 
( Xa  tural 


3.    Tortrix  (lu'tiiiia)  JiaoUana,  Schiff.  {Vine-shoot  Toitrix)* 
a.  iJescriplion. 
Moth  with  wing-expansion  of  19   to  22  mm.  ;    fore- wings 
narrow,  reddish-yellow,  traversed  by  6 — 7  broad,  wavy  y-shaped 

•    ]'i(Ir  Alis-s  Ormerod,  oj>.  cit.,  p.  248. 


336  PROTECTION    AGAINST    INSECTS. 

silvery  marks,  hind-wings  dark  grey  ;  both  pairs  with  light 
grey  fringes.     Thorax  orange,  abdomen  grey. 

Caterpilhir  14  mm.  long,  with  10  prolegs,  bright  brown  and 
smooth,  the  head  and  first  segment  black. 

Pupa  yellowish-brown,  with  a  row  of  fine  prickles  on  the  back 
of  the  abdomen. 

/'.  Life-h is/or//. 

The  moth  appears  from  the  end  of  Jane  till  the  end  of  July. 

During  the  day  it  sits  somewhat  concealed  amongst  the  pine 
needles,  its  colour  assimilating  with  the  withered  pine  shoots, 
but  it  becomes  active  with  the  approach  of  twilight.  The  eggs 
are  laid  among  the  terminal  buds  of  young  Scots  pine  plants. 
The   caterpillars   hatch   out   at   the   end  of  August   and   in 


^^1^^ 


Fig.  ITl.—  Torlrix  huoUana,  Schiff. 
a  Imago,     h  Larva,     e  Pupa. 

September,  tliey  hibernate  in  the  Inids,  becoming  full  grown  in 
the  following  May. 

Pupation  takes  place  at  the  end  of  May  or  June,  at  the  base 
of  the  injured  shoot.  Tiie  pupa  is  exposed,  and  the  empty 
pupal  case  may  be  seen  for  some  time  on  the  shoot. 

The  moth  emerges  4  weeks  later. 

Generation  annual.  The  insect  is  common  and  widely 
distributed  wherever  Scots  pine  trees  are  grown  in  Europe. 

c.  Relations  to  the  Forest. 

The  Scots  pine  and  occasionally  the  Weymouth,  l)lack  and 
cluster  pines  are  attacked.  * 

The  insect  exclusively  attacks  young  growth,  and  prefers 
weakly  G-  to  12-  year-old  plants  on  poor  soil  and  in  sunny 
situations. 


TORTRIX    BUOpAJ^A. 


3:3? 


The  attack  is  made  by  the  larva  boring  into  buds  and  shoots. 
Late  in  the  summer  the  buds,  particuhirly  the  terminal  buds, 
are  slightly  gnawed  at  their  base,  so  that  turpentine  exudes. 
In  the  following  spring,  as  soon  as  the  plant  begins  to  shoot 
up,  the  caterpillar  bores  right  through  the  pith  of  the  young 
shoots.     Shoots  eaten  on  one  side  become  curved  as  in  the 


\      A 


%.-^'H 


...  ^'. . 


/ 


Fig.  173.— Pine-braucli,  showing  distortion  after  antecedent  injury  by  T.  huolinna 
Schiff.     A  larval  gallery  is  exposed  in  the  broken  shoot,  a.     {Natural  size.) 


figure,  and  if  no  further  injury  is  done,  will  recover  their 
vertical  position,  but  the  perforated  shoots  dry  up,  turn  brown 
and  fall  ofif.  After  destroying  the  terminal  shoot,  the  larva 
directs  its  attention  to  the  side  shoots ;  it  sometimes  spins 
several  together,  and  passes  from  one  to  another.  The  attack 
can  be  distinguished  from  that  of  the  pine  beetle  by  the 
crumbling  excrement  found  in  the  borings. 

The  injury  causes  the  pine  to  send  out  brush-like  shoots  as 

F.P.  Z 


33S  I'ROrKCTION    AflAINST    INSECTS. 

lateral  buds  develop  on  all  sides  of  the  point  of  attack,  and 
the  resulting  loss  of  increment  is  consideral)le,  as  fre(juently 
the  pest  recurs  year  after  year. 

(I.  Proter/ire  IhiJes. 

Protection  of  birds,  titmice,  etc. 

Careful  planting  and  rearing  of  plantations  of-  vigorous 
pines,  without  undue  crowding. 

The  shoots  which  are  attacked  may  be  broken  oft'  and 
burned,  from  the  middle  of  May  to  the  end  of  June.  This 
plan  is  advisable  only  on  small  areas  and  at  the  commence- 
ment of  the  attack.  If  made  late,  it  destroys  numerous 
parasitic  enemies  of  the  caterpillars. 

Eemoval  of  all  misshapen  stems  at  the  firi5t  thinning,  till 
which  time  they  are  spared  to  help  to  cover  the  ground. 

4.   Tortrix   {Rctinui)  tiirionaiia,  Hb. 
a.  Description. 
Moth   with   a   wing-expanse   of   16 — 18   mm. ;    fore-wings 
brown-grey,  ochreous  towards  the  tip,  with  leaden-grey  trans- 
verse wavy  lines;  hind- wings  whitish,  the  tip  greyish  ( J  )  or 
ochreous  (  ?  ).       Head  and  thorax  ochreous;  abdomen  grey. 
Larva  10  mm.  long,  with  16  legs  ;  light  brown,  with  Ijlack 
head  and  thoracic  shield. 

b.  Lifp-liinlory,  etc. 

The  eggs  are  laid  in  May  or  June  singly  on  the  middle  buds 
of  the  whorls  of  the  stem  of  young  Scots  pines  (usually  5 — 15 
years  old).  The  caterpillar  bores  as  a  rule  into  the  middle 
bud,  and  hollows  out  the  pith-canal  in  the  course  of  the 
summer.  The  shoot  is  checked  from  the  commencement  of 
its  growth  and  takes  on  a  blackish-grey  colour ;  eventually  it 
dies  and  the  lateral  buds,  which  are  seldom  attacked,  become 
abnormally  large. 

Pupation  takes  place  in  the  following  year  (at  the  end  of  April 
or  in  May)  in  the'  hollowed  bud,  which  is  spun  over  with  a 
thin  web,  and  the  moth  emerges  at  the  end  of  May  or  the 
beginning  of  June. 


TORTRIX    RESINKLLA. 


339 


Other  species  of  pine,  such  as  the  Wpymouth  pine  and  Pimis 
ponderosa,  Dough,  are  hahle  to  attack.  The  insect  is  less 
common  than  the  preceding. 

r.   l!r))if(lit/l  Measures. 

The  injured  buds,  which  can 

be    recognised    by   their   small 

size  and  dark  colour,  should  be 

cut  off  towards  the  end  of  April. 

5.  Tortrix  {lietinia)  resineUa,  L. 
a.  Descripiion. 

Moth  with  a  wing-expanse  of 
16  to  18  mm. ;  fore-wings  slaty- 
grey  with  numerous  shining 
leaden  -  grey  transverse  lines 
forked  on  the  fore-margin ; 
hind  -  wings  grey  -  brown  ;  the 
fringes  pale.     Body  slaty-grey. 

Caterpillar  11  mm.  or  more 
in  length,  with  16  legs,  orange- 
brown,  with  brownish-red  head 
and  thoracic  shiehl. 

/'.  Lifr-liisloiij. 
The  eggs  are  laid  in  May  and 
June,  just  under  the  whorl  of 
buds  of  the  recently  -  grown 
shoots  of  young  pines,  usually 
on  the  lateral  shoots.  The 
caterpillar  bores  into  the  pith 
and  thus  causes  the  growth  of 

a  hollow  gall-like  resinous  mass,  as  large  as  a  pea,  in  which  it 
passes  the  winter.  In  the  spring  it  continues  feeding,  causing 
the  gall  to  increase  'to  the  size  of  a  cherry  or  of  a  small 
walnut,  and  form  a  swelling  on  the  underside  of  the  shoot 
which  encircles  two-thirds  of  it.  On  section  the  gall  is  seen 
to  be  divided  into  two  compartments  by  a  strong  vertical 
partition.     In  the  larger  one  the  larva  lives  and  pupates  (in 

z2 


Fig.  174.— Resin-gall  of  T.  resi- 
nc/la,  L.,  on  a  pine  shoot. 
(^Xutinal    size.') 


340  PROTECTION    AGAINST    INSECTS. 

April  or  May  of  the  tliird  year)  ;  the  smaller  one  contains  its 
excrement. 

The  moth  flies  about  May ;  the  generation  extending  over 
two  years.  As  a  rule  the  pine  recovers  its  injuries  ;  but  in  an 
unfavourable  situation  or  after  bad  weather  the  attacked  shoots 
perish.  Tlie  species  is  tolerably  common  in  a  few  localities 
in  Scotland  and  in  Windsor  Forest. 

The  treatment  consists  in  the  destruction  of  the  galls  during 
the  second  Avinter,  and  in  cutting  off  affected  shoots. 


G.   Tortrix  rufimitrana,  H.-Sch. 
a.  Descrqi/i(m. 

Moth  with  wing-expansion  of  12-lG  mm. ;  fore-wings  dark 
greyish-brown,  with  lead-coloured  wavy  lines  at  their  base,  a 
rusty  yellow  median  band  with  a  lead-coloured  border,  and  a 
round  dark  spot  on  a  rusty  yellow  patch  near  the  corner  of  the 
wings  ;  hind-wings  brownish  grey,  with  grey  fringes  ;  thorax 
rusty  yellow  near  the  head,  abdomen  brownish-grey. 

Caterpillar  10  mm.  long,  with  10  prolegs,  of  a  dull  yellowish- 
green  above  and  yellow  below,  with  reddish-brown  head. 
Piij)a  G  mm.  long,  bright  brown. 

//.  Life-hislonj. 

The  moth  Hies  from  June  till  the  end  of  July,  sometimes 
also  in  IMay.  The  eggs  are  laid  on  silver-fir  needles,  where 
they  remain  during  the  winter. 

The  caterpillars  hatch  in  the  succeeding  spring,  and  when 
fully  grown  at  the  end  of  June,  let  themselves  down  by  threads, 
and  pupate  in  the  soil-covering  in  a  cocoon  made  of  silk  and 
bits  of  earth.  The  moth  api)ears  2  to  3  weeks  later.  Genera- 
tion annual. 

r.  Ueldlions  lo  llto  Forest. 
The  caterpillar,  commencing  operations  as  the  young  shoots 
appear  in  May  or  the  beginning  of  June,  eats  the  needles  and 
youngest  shoots  of  the  silver-lir.  It  devours  the  young 
needles,  bites  oft'  the  older  ones  at  their  base  and  gnaws  the 
epidermis  of  the  young  shoots,  spinning  a  thin  web  over  the 


TORTRIX    PINICOLANA.  3il 

parts  attacked.  The  insect  prefers  woods  of  60  to  100  years 
old,  but  when  the  moth  appears  in  swarms,  younger  wood  is 
also  attacked.  The  edges  of  the  crowns  of  the  trees  become 
reddish,  and  after  attacks  repeated  for  several  years  the  trees 
become  stag-headed,  the  topmost  branches  being  as  bare  as 
brooms,  and  die.  There  have  been  several  severe  attacks  in 
Germany  on  silver-fir  by  this  moth  since  1876,  and  in  1879, 
1,800  acres  of  forest  were  ravaged  in  Nagoldthal,  and  the  attack 
spread  to  the  surrounding  districts. 

(I.   Pnilorlivc  Hnle^. 
Mixture  of  otlier  species  with  the  silver-fir,  and  clean  wood- 
craft. 

Protection  of  enemies  :  titmice,  the  wren,  etc. 

e.  Remedial  Jfemures., 

Smoking  out  the  caterpillars*  by  burning  green  branches  in 
damp  weather.  This  is  done  in  May,  by  thinning  affected 
woods  and  collecting  branches  from  trees  and  poles  felled, 
which  are  burned  in  heaps  after  taking  necessary  precautions. 
In  damp  weather  the  smoke  penetrates  the  leaf-canopy 
and  causes  numbers  of  larvae  to  fall,  which  are  swept  into  the 
fire.  This  was  done  by  Forstmeister  Kocli,  with  excellent 
results,  near  Karlsbad. 

Admission  of  pigs  to  the  forest  as  soon  as  the  cocoons  are  in 
the  soil  covering,  during  the  first  half  of  June. 

Raking-up  and  removing  the  soil-covering  whilst  the  pu[)ae 
are  there. 

Felling  trees  which  are  badly  attacked. 

7.  Tortrix  pinicoluna,  Zll. 
a.  Descri/)/i())i. 
Moth  with  wing-expansion  of  18  to  22  mm.  ;  fore-wings  long, 
with  strongly  sinuate  ijaner  border,  bright  ashy-grey,  with 
numerous  dark  brown  wavy  stripes  ;  hind-wings  somewhat 
broad,  of  a  uniform  brown  or  ashy  grey  colour  ;  both  pairs 
with  brownish-white  fringes. 


Ui 


I'KOTFXTIOX    A(;.\IXsr    IXSI-XTS. 


Caterpillar  10  mm.  long,  with  10  prolegs,  dark  green,  darker 
on  the  back,  with  two  brighter  green  stripes  along  the  sides; 
head  and  prothoracic  sliield  shining  black. 

/'.  Lifc-]iis((irij. 

The  molli  ajipoars  in  August  and  the  beginning  of  Septem])er. 

The  eggs  are  laid  at  the  base  of  young  larch  shoots,  and 
remain  over  winter.  The  caterpillars  appear  in  May  or  June, 
and  pupate  at  the  end  of  July  or  in  August  in  a  silken  cocoon 
amongst  the  needles,  on  twigs  or,  when  the  insect  is  very 
numerous,  in  bark  cracks,     (ioicratioii  annual. 


^- 


1 

Fig.    I'o.—Tortrix   pi 
colli i/a,  'AW. 


c.  Kel//lioHs  III  (he  Forest. 

The  caterpillars  usually  attack  only  old  larch,  and  chiefl}' 
sickly  trees,  but  when  very  numerous 
they  also  attack  healthy  trees,  and 
underwood  of  spruce  or  P.  C'cmtira 
growing  below  the  larch.  They  eat 
the  needles,  at  first  those  of  the 
lower  shoots,  subsequently  climbing 
to  the  summit  of  the  trees.  The 
insect  sometimes  appears  in  such 
numbers  as  to  comjjletely  strip  the 
trees  of  needles,  and  entire  woods 
may  then  appear  with  a  brown 
canopy,  as  if  the  needles  had  been  burned.  As  a  rule 
fresh  needles  appear  during  an  attack,  but  if  it  should  lasl  for 
2  to  3  years,  even  the  healthiest  trees  will  succumb.  Badly 
stocked  woods  on  shallow'  soil  and  with  a  southerly  aspect 
suffer  most  of  all. 

This  insect  is  common  in  Switzerland,  and  has  been 
observed  over  fairly  large  tracts  of  forest  in  1855-56-57, 
18(;4-r)5,  187H-7!)  in  the  Ober  Engadin,  Wallisand  Graubundt. 
In  187J)  in  llio  Ober  Engadin,  where  larch  is  the  dominant 
species,  over  15,000  acres  of  forest  were  attacked  ])y  it.  Also 
in  1889,  in  the  Tyrol.  It  is  not  uncommon  among  larches  in 
liritain. 


TINEA    VARIABILIS.  343 

(I.  Protective  Rules. 
Protection  of  birds. 
Smoking  out  as  described  for  the  preceding  species. 

Family  VII. — Tineidae. 
Description  of  Family. 

Ima'jos  with  long  fiUform  or  setaceous  antennae,  seldom 
pectinate ;  ocelli  usually  present ;  wings  long  and  narrow, 
usually  pointed,  and,  especially  the  hind-wings,  characterised 
by  long  fringes,  during  repose  either  roof-shaped  or  folded  over 
the  body  ;  frenulum  present ;  legs  stoutly  spurred.  Generation 
annual. 

Caterpillars  slightly  hairy,  usually  with  10  prolegs.  A  few 
species  have  only  6  to  8  prolegs,  and  those  reduced  in  size  (leaf- 
miners). 

Pupation  usually  in  a  cocoon.  Pupae  with  a  thin  hairless 
skin,  rarely  with  spines  on  the  abdominal  segments,  but  cha- 
racterised by  the  elongate  wing-cases  which  reach  almost  to 
the  apex  of  the  abdomen. 

The  caterpillars  generally  live  in  rolled-up  leaves,  or  in 
shoots,  flowers,  fruits,  seeds,  etc.  Many  species  are  leaf- 
miners,  living  on  the  parenchyma  of  leaves,  between  the  upper 
and  lower  epidermis.  Others  bore  into  the  pith,  wood,  liark 
or  buds.  Few  of  them,  however,  are  important  enemies  of 
the  forest. 

1.    Tinea  {Uijpononieuta)  variabilis,  Zell. 
a.  Description. 

Moth  with  wing-expanse  of  18  to  20  mm. :  fore- wings  white, 
clouded  with  brownish  grey  on  the  anterior  border,  with  3 
irregular  longitudinal  rows  of  black  spots,  and  a  group  of 
smaller  spots  along  the  outer  margin  ;  hind-wings  brown- 
grey  ;  fringes  pale-grey  or  whitish. 

Caterpillar  18  mm.  long,  with  16  legs,  yellowish-grey,  marked 
with  round  black  spots,  with  black  head  and  thoracic  shield. 
Pupa  light  brown. 


344  PROTIX'TION    AGAINST    INSECTS. 

h.  Life-hislory,  eir. 

The  eggs  are  laid  at  the  end  of  June  and  in  July  on  buds, 
usually  of  underwood.  The  larvae  do  not  hatch  till  the  spring, 
when  they  attack  buds,  leaves  and  blossoms  under  the  protec- 
tion of  a  conspicuous  gauzy  web,  which  they  spin  in "  common 
over  the  ends  of  the  branches. 

The  chief  food-plants  are  the  plnni  and  iipi)le  trees,  the 
mountain-ash  and  esi)ecially  the  hawthorn.  This  caterpillar 
has  also  committed  great  ravages  among  willows  in  Hungary. 
It  is  very  common  in  the  British  Isles,  and  often  completely 
defoliates  hawthorn  trees  and  hedge-rows  in  the  open  spaces 
of  London.  Pupation  takes  place  on  the  branches  or  trunk  in 
June  or  July  in  a  white  cocoon. 

c.  Rcmediid  Measures. 

Cutting-off  and  destruction  of  the  caterpillar-webs  at  the 
beginning  of  June.  Destruction  of  the  moths  (July),  which 
often  sit  in  conspicuous  groups  at  a  moderate  height  on  the 
trunks. 

Where  defoliation  is  an  eyesore,  as  in  public  parks,  the  trees 
may  be  carefully  sprayed  with  a  weak  arsenical  mixture  or 
syringed  with  a  stronger  jet  of  plain  water  or  soap-mixture. 

Other  species  of  Tinea — e.g.  T.  j^adi,  Zell.,  on  the  gean 
{Priuiua  padns,  L.)  and  on  Ilhammis  Fraiujida,  L. — are  closely 
allied  in  appearance  and  habits. 

2.   Tinea  ruiiisella,  Don.  {A.sli-liriji  M<>lh). 
a.  Dcficripliun. 
Molh  with  a  wing-expanse  of  16  mm.;  fore-wings,  head  and 
thorax    white  ;    the     former 
..-^^  with  a  large  triangular  dark- 

"        "^'      grey  blotch    on    the  anterior 
margin    and  with    the    base 
and    outer    margin    clouded 
[^l  with  blackish    marks;   hind- 

4/,  wings    and     abdomen    grey- 

Fig.  nG.—Tiiirn  curihcUa,  D^di.  browu,  the  latter  lighter  be- 

neath ;  fringes  grey-brown. 
Caterpillar    7     to    10    mm.    long,    witli     10    logs,     l)right 


TINEA    CURTISELLA. 


34-5 


honey-yellow  with  brown  head  and  dorsal  shield.     (According 
to  Stainton  the  larva  is  greenish,  marbled  with 
reddish-brown.) 

Pii])a  yellow-brown,  glossy,  in  a  neat  cocoon, 
pointed  at  each  end  and  of  a  silken  lustre, 
constructed  away  from    the  larval  feeding-place. 

//.  Lifc-liislonj. 

The  Dtoth  flies  in  June  and  lays  its  eggs  on 
the;  leaves  of  ash,  which  are  mined  in  July  by 
the  newly-hatched  larva.  The  larvae  pupate  early 
in  August  on  the  ground  among  dead  leaves. 
After  eight  days'  pupation,  the  moth  appears  in 
the  middle  of  August  and  lays  eggs  on  the  leaves. 
Generation  double.  In  the  autumn,  when  the 
leaves  turn  yellow  and  fall,  the  caterpillar,  which 
is  still  very  small,  after  mining  the  leaves  till 
near  leaf-fall,  bores  into  the  sheathing  scales  of  the 
terminal  buds ;  here  it  moults  and  excavates  a 
hole  in  which  to  hibernate.  Its  presence  is  indi-  '■'■-•  ^"■~ 
cated  by  the  fine  powder  visible  in  the  entrance-  inhabited 
burrow.  As  soon  as  the  buds  begin  to  swell  in  by  larvae  of 
the  ensuing  spring,  the  caterpillar  begins  to  feed  •'^^'^  "  *"''° 
on  the  buds,  and  reaches  maturity  about  May.  ^  Exuded 
The  injured  bud  is  incapable  of  development  and  excrement, 
is  outstripped  in  growth  by  the  next  uninjured  iXatnrai 
shoot,  causing  the  ends  of  the  branches  to  become  ^'"""-^ 

forked.  The  larvae  then  generally  attack  the  leaves  again, 
and  pupate  at  the  end  of  May,  the  pupa  being  attached  by 
a  thread  to  a  twig.  Chiefly  young  plants  and  saplings  are 
attacked.  The  summer  attack  is-  harmless,  but  the  spring 
attack  causes  forking. 

The  species  is  tolerably  common  wherever  ash  is  grown. 


r.  Retnedial  Measures. 
Cutting  off  the  injured  buds  early  yi  July,  together  with  one 
of  the  adjacent  lateral  buds.     This  prevents  forking  but  is 
practicable  only  in  nurseries  and  on  saplings. 


346  PROTECTION    ACJAINST    INSKCT.S. 

3.  CoU'oplitira  lar'udla,  Hbn.  {Tjarch-ninicr  Moth), 
a.  Desrrip/ion. 
Moth    \Yith    AYJng-expansion  of  9  to  11  mm.;    win<^s  very 
narrow,  shining  ashy-grey,  with  very  long  fringes,  especially 
to  the  hind-wings. 

Caterpillar  4  to  5  mm.  long,  with  10  prolegs,  dark  reddish- 
brown.  Pupa  4  to  5  mm.  long,  narrow,  dark  brown,  with  fine 
bristles.  ^ 

//.  Lifp-liistorij. 
The  moth  flies  in  the  daytime  in  May  and  June. 
The  ?  laj^s  its  little  roundish  yellow  eggs  on  healthy  larch 


Fig.  178. — Coleophora  laricella,  Hbn. 
a  Moth,     h  Caterpillar,     c  Larval  case,     d  Pupa. 

needles,  usually  only  one  egg  on  a  needle.  After  6  to  8  days 
the  eggs  become  grey. 

The  caterpillars  hatch  in  June,  and  continue  to  grow  till 
September.  They  hibernate  on  the  needles  in  a  case.  The 
pupal  stage  is  passed  from  the  middle  of  April  till  May  in  a 
case  on  the  needles.  The  moth  emerges  in  the  latter  half 
of  May. 

Generation  annual.  Very  common.  The  caterpillar  is  very 
susceptible  to  late  frosts,  wet  and  cold  rainy  weather  and  hail. 

r.  liclalions  lo  llic  Forr.sf. 

This  insect  is  a  most  dangerous  enemy  of  the  larch,  and 
prefers  10-  to  40-year-oId  trees,  but  may  also  attack  woods 
which  are  older  or  younger  than  these.  AVhen  other  nutriment 
fails,  the  insect  attacks  young  spruce  or  pines  that  are  either 
under  or  among  the  larches. 


COLKOPHORA    LAUICKLLA. 


347 


The  little  caterpillar,  as  soon  as  it  has  emerged  from  the 
egg,  bores  into  the  young  larch-needles  to  about  half  their 
length,  so  that  their  upper  ends  shrivel  up  and  turn  yellow,  as 
if  injured  by  frost.  The  attack  usually  commences  on  the 
lower  branches  and  proceeds  upwards,  the  top  of  the  tree 
being  spared  in  moderate  attacks. 
The  appearance  of  a  plant  which 
bears  a  large  number  of  infested 
needles  is  very  conspicuous  and 
characteristic. 

In  September  the  fully  grown 
caterpillar  prepares  a  little  case  out 
of  the  dry  part  of  the  needle,  which 
it  cuts  off  for  the  purpose,  and  in 
this  it  hibernates  on  the  twigs, 
usually  at  their  tips,  or  in  bark- 
cracks,  or  among  lichens  on  the 
stems. 

In  the  spring  the  caterpillar,  carry- 
ing its  case  with  it,  bores  again  about 
half-way  into  a  larch  needle,  and 
about  the  middle  of  April  finding  its 
old  case  too  small,  it  fastens  it  along 
the  freshl}^  hoUowed-out  needle,  like 
two  fingers  of  a  glove.  It  then  cuts 
out  the  adjacent  walls  of  its  old  case 
and  of  the  needle,  thus  preparing  a 
new  case  twice  as  wide  as  the 
former.  This  troublesome  work  occu- 
pies several  days,  during  which  an 
observer  might  imagine  that  there 
were  two  larvae  on  a  needle.  When 
the  insect  is  ready  for  pupation  it  spins  the  new  case  firmly 
to  a  needle.     . 

The  little  insect  likes  sunny  warm  localities,  sheltered  from 
the  north  and  east,  and  prefers  the  westerly  borders  of  woods, 
avoiding  isolated  trees,  probably  on  account  of  their  exposed 
position.  It  has  been  observed  in  Switzerland  up  to  an 
altitude  of  3,000  feet,  and  in  Germany  and  Britain  it  constantly 


Fig.  179.  —Larch -needles  in- 
jured by  C.  laiicclla,  Hbn. 
[Xatiiral  size.) 

a  Larval  cases.  h  Spinning 
catei-pillars.  c  Hollowed 
and  twisted  needles. 


348  PROTECTION    AOAINST    INSKCTS. 

accompanies  the  larch,  and  has  recentl}'  ])ecome  al)undant  in 
Switzerh^nd,  where  the  larch  is  indigenous.  It  sometimes 
appears  in  myriads,  50,000  larvae  having  been  found  on  a  plant 
only  12  years  old  in  Schlucken,  1895. 

Independently  of  its  large  numbers  and  wide  dissemination, 
its  great  hurtfulness  results  from  its  eating  the  needles  twice 
during  the  same  year,  and  appearing  year  after  year  in  the 
same  localities.  As  the  larch  disease  almost  always  accom- 
panies  this  insect,  the  latter  probably  renders  the  tree 
susceptible  to  this  highly  destructive  fungus.  The  loss  of 
increment  is  considerable,  owing  to  the  destruction  of  needles 
in  the  spring,  so  that  trees  are  often  so  weakened  by  repeated 
attacks  that  they  die. 

(L  Proieciive  Rules. 

Choice  of  suitable  localities  for  larch,  and  planting  it  widely 
apart. 

Mixture  of  larch  with  beech,  spruce,  silver-fir,  etc. 

Early  thinning,  and  removal  of  the  thinned  material,  at  the 
latest,  by  the  end  of  March. 

Protection  of  titmice  and  other  small  birds. 

c.  Remedial  Measures. 

Pruning  the  lower  branches  of  larch  trees,  on  which  the 
insect  usually  appears. 

Piemoval  of  badly  attacked  and  weakened  trees  from  the 
middle  of  June  till  the  end  of  August.  The  caterpillars  in  the 
needles  of  these  trees  will  not  then  become  fully  developed. 

The  little  cases  may  be  picked  off  the  trees,  and  destroyed 
during  the  winter  and  spring,  but  this  plan  can  be  followed  in 
forest  nurseries  only. 


349 


CHAPTER   VIII. 

DESTRUCTIVE    INSECTS    {coiicludcd) . 

A.  Hymenoptera. 

Family  I. — Tenthredinidae  (Sawflies). 

Description  of  Family. 

Sawflies  have  straight,  usually  filiform  or  setaceous 
antennae,  rarely  club-shaped,  occasionally  serrate,  or  in  S 
doubly  pectinate,  and  with  3  to  30  joints ;  3  ocelli ;  prothorax 
usually  very  short ;  wings  with  full  complement  of  veins,  the 
fore-wings  with  1  or  2  radial  and  3  or  4  cubital  cells. 

Legs  with  a  double  trochanter  ;  the  anterior  tibiae  with 
two  apical  spines  ;  tarsal  joints  often  furnished  below  with 
membranous  expansions,  sometimes  cup-shaped. 

Abdomen  sessile,  of  8  segments ;  in  2  .with  protrusible 
serrate  ovii)Ositor. 

Generation  usually  double,  sometimes  treble,  but  in  the 
cocoon-spinning  sawflies  it  may  be  plurennial. 

Larrae  usually  bright-coloured,  with  8  or  18  to  22  legs, 
resenibling  caterpillars  but  distinguishable  usually  by  the 
greater  number  of  legs  and  by  a  conspicuous  simple  e3'e  on 
each  side  of  the  head  ;  they  are  social,  and  after  5  to  0 
moultiiigs  spin  a  firm  cocoon  which  is  of  oval  or  oblong-oval 
form  and  often  parchment-like  in  consistency. 

Pupation  takes  place  in  the  cocoon  about  2  weeks  before  the 
sawfly  emerges.  The  pupae  are  soft,  and  encased  in  a  barrel- 
shaped  cocoon. 

The  larvae  feed  on  needles  and  leaves ;  they  are  often  social 
when  young,  and  when  disturbed  assume  a  characteristic 
S-like  attitude.  The  perfect  injects  usually  feed  on  honey. 
Some  species  (Cimbex)  girdle  young  beech-shoots  probably  in 
order  to  get  the  sap.     A  few  species  are  very  destructive. 


350 


PROTKCriOX    AdAIXST    IXSECTS. 


1.   L()])]ii/niH  i)ini,  L.   (Pine  Sairjltj). 

(1.  /Jesrrijilio/K 

Male  with  a  wing-expansion  of  15 — 16  mm, ;  body  black, 

abdomen  reddish  at  apex,  spotted  with  white  on  the  underside 

of  the  first  segment ;  antennae  douljly  pectinate  ;  hind-wings 

with  a  dark  border. 

Female  with  a  wing-expansion  of  18 — 20  mm, ;  body  dull- 
yellow,  with  the  head,  3  spots  on  the  thorax,  and  the  middle 


T 

FiK.  ISQ.—Lop/ii/nispitii.  ] 
a  Male.          //    Feni:.]('. 

1 

of  the  broad  abdomen  alone  blackish  ;  wings  yellowish,  slightly 
infuscate  along  the  outer  margins. 

Legs  yellow  in  both  sexes. 

Larva  25  mm.  long,  with  22  legs,  changing  colour  as  it 
becomes  older,  finally  of  a  dull  green,  Avith  oblique  rows  of 
little  rugosities  and  a  round  brown  bead,  and  black  semicolon- 
shaped  marks  above  tlie  prolegs, 

Piijnt  enclosed  in  a  10  mm,  long,  leathery,  and  usually  dark 
brown  cocoon. 

b.  Life-history. 

The  sawfly  appears  in  April  and  May,  and  again  at  the  end 
of  July  and  in  August,  Only  the  <?  appears  to  fly.  The 
much  more  numerous  ?  creep  lazily  along  the  twigs  and 
needles.  The  ?  in  April  and  early  in  May  cuts  slits  into 
Scots  pine  needles  with  her  saw-like  ovipositor,  and  lays 
a  sausage-shaped  egg  in  each  slit,  depositing  10  to  20  hi  each 


PINE    SAWFLY. 


351 


needle,  and  80  to  120  altogether ;  she  seals  up  each  egg  with 
a  frotli}^  secretion. 

The  larvae  hatch  2  to  3  weeks  later,  in  May  and  June,  and 
those  of  the  second  brood  in  August  and  September.  They 
frequently  moult,  the  empty  skins  hanging  on  the  needles. 
The  second  brood  hibernate  in  cocoons  under  moss,  or  on 
stems  or  twigs.  There  is  not,  however,  always  a  second 
brood,  and  the  larvae  of  the  first  brood  may  then  hibernate. 
Pupation  takes  place  at  the  beginning  of  July  *  in  a  compact 
brown  cocoon,  among  the  needles,  or  in  bark-cracks  on  the 
stems  of  the  pine.  The 
second  brood  pupate  in 
March  or  April  in  cocoons 
under  moss  at  the  foot  of 
the  tree  they  have  attacked. 

The  sawJiU'S  of  the  first 
brood  appear  at  the  end  of 
July  or  early  in  August, 
about  2  to  3  weeks  after 
pupation.  The  insect  when 
ready  for  flight  cuts  a  cir- 
cular hd  off  the  cocoon. 
If  an  ichneumon  fly  should 
emerge  instead  of  the  saw- 
fly,  a  little  hole  appears  at 
the  end  of  the  cocoon  (0) 
instead  of  the  lid.  The 
second  brood  usually  emerge  in  April,  but  sometimes  not  till 
July,  when  the  sawfiies  of  the  two  broods  become  intermingled. 

Genevation  double,  but  frequently  lasting  over  a  year.  In 
rare  cases  it  has  lasted  for  2  to  3  years.  The  insect  is  very 
common  on  tlie  continent  of  Europe  and  in  the  British  Isles. 

The  naked  larvae  are  susceptible  to  cold  and  wet  weather. 

c.  Relations  lo  Forest. 
The  larvae  attack  the  Scots  pine,  and  prefer  sickly  poles 
wliere  the  leaf-canopy  has  been  interrupted,  20  to  30  years 

•  Theodor  Hartig  states  that  cocoons  spun  under  moss  are  dull  brown,  and 
those  on  the  tree  silky  ash-grey,  dirty  white,  or  yellowish.  Even  clean  white 
and  rusty  red  cocoons  may  occur. 


LSI.— Pine-needlcs 
cocoon  of  L.  pi 


li   larvae  and 
L. 


352 


ri;()Tl>:CTION    AOAIXST    INSECT; 


old,  on  poor  soils  and  with  a  sunny  aspect.  They  also  attack 
young  growth  and  trees  up  to  the  age  of  120  years.  Border 
trees  especially  suffer. 

The  larvae  till  half-grown  eat  the  needles  in  dense  companies 
of  60  to  80  and  more.  When  young  they  merely  gnaw  the 
edges  of  the  needles ;  later  on  they  eat  them  in  short  strips 
parallel  to  the  mid-rib,  which  they  leave  intact.     An  attack 


Fig.  182. — 3  cocoons  of 
the  Pine  sawfly  on 
pine  bark. 

{Natural  size.) 


Fig.-  183. — 2  empty  cocoons  of  tli( 
I'inn  sawfly  on  an  oak-t\vi'_'.  Tlu 
lilipcT  oik;  lias  lost  the  lid. 


by  the  pine  sawfly  may  be  at  once  recognised  by  the  remaining 
yellowish,  thread-like  mid-ribs  (Fig.  184). 

The  older  caterpillars  only  leave  short  stumps  to  the  needles. 
The  first  brood  chiefly  devour  1-year-old  needles,  and  the 
second  brood  those  of  the  current  year.  The  larvae  also  gnaw 
the  soft  young  bark  in  patches,  often  down  to  the  wood. 
After  the  crowns  of  larger  poles  are  stripped,  smaller  Scots 
pine  poles,  underwood,  and  young  [ilantations  are  attacked. 


PINE    SAWFLY 


353 


This  and  all  other  species  of  Lophyrus  have  the  habit,  when 
disturbed,  of  l)ending  the  front  part  of  their  bodies  in  the 
fi-;ure  S  {cidc  Fig.  181). 

d.  Prolerlive  Rides. 

i.  Maintenance  of  healthy 
well  -  stocked  Scots  pine 
woods,  so  that  the  soil  may 
not  be  impoverished. 

ii.  Protection  of  enemies  : 
cuckoo,  starling,  crow,  goat- 
sucker, swallows,  etc.  ]\Iice 
and  squirrels  open  the 
cocoons  during  the  winter, 
and  devour  many  larvae. 
Even  the  badger  and  fox 
eat  the  larvae  and  pupae. 

Many*  parasitic  ichneu- 
mon wasps  and  Dlptem 
attack  the  larvae.  So  do 
spiders,  c.(j.,  Steatuda  sist/- 
pliia,  CI. 

c.  Remedial  Measures. 

i.  Collection  of  larvae  by 
stripping  or  shaking  them 
from  the  trees  on  to  cloths 
spread  on  the  ground,  in 
;May  and  June,  and  again 
in  September  and  October. 
One  man  shaking  the  trees, 
with  two  boys  to  collect  the 
larvae,  can  clear  fifteen  25- 
year-old  trees  before  9  a.m.,  and  such  work  is  most  efficacious 
in  the  morning  when  the  larvae  are  slightly  torpid. 

ii.  Collection  of  cocoons  under  the  moss  in  winter.  They 
may  be  found  generally  near  the  base  of  the  attacked  trees, 
and  sometimes  in  masses  as  large  as  the  fist. 

iii.  Admission  of  pigs  in  September  and  October,  when  the 

•  For  a  list  of  tbcsc,  ride  Tascbenberg,  c/a  cit.,  page  230. 
K  1'  A  A 


Fig.  184. — Pine-shoot  with  needles  eaten 
by  Z.  pini,  L.     (Natural  size.) 


354  PROTJ'XTION    A(;AINST    INSECTS. 

larvae  come  down  to  hibernate.  The  pigs  Mill  not  eat  the 
cocoons,  which  are  too  tough  for  their  taste,  but  crush  them 
in  mimbers. 

iv.  Planks  smeared  with  tar  ma}'  ]>e  put  up  to  catcli  the 
sawflies,  the  tarred  sides  being  turned  towards  the  suii,  and 
the  tar  renewed  from  time  to  time. 

V.  Mixture  of  quicklime  with  the  litter  and  then  watering  it. 
The  heat  thus  engendered  kills  the  larvae  and  pupae  that  are 
in  the  litter,  and  preserves  the  latter  for  the  forest.  This 
remedy  was  tried  with  success  on  6  acres  oE  12 — 15  Scots 
pine  plantation  with  heather  undergrowth,  and  cost  12s. 
an  acre. 

vi.  If  no  other  remedy  should  be  found  effective,  the 
damaged  wood  must  be  cut  down,  and  the  roots  grubbed  up 
late  in  the  summer  or  winter  ;  branches  may  be  spread  on  the 
soil  and  burned  before  grubbing  up  the  roots,  and  one  or 
two  field-crops  harvested  before  the  land  be  restocked  with 
pines. 

Several  other  species  of  Loplnjnis  of  generally  similar  habits 
also  attack  Scots  pine.  Miss  Ormerod*  states  that  much 
injury  was  done  in  1890  to  three  or  four  thousand  acres  of 
young  Scots  pine  in  Argyleshire  by  L.  ru/its,  Klug,  the  larvae 
of  which  are  dull  greenish-grey,  with  black  heads.  The  Hies 
appeared  in  August  only,  and  the  ?  are  reddish  and  the  J 
black ;  both  sexes  have  red  legs. 

Plants  2  to  6  feet  high  were  more  subject  to  attack  than 
older  ones.  In  Germany  the  sawllies  appear  in  May,  and  the 
larvae  May — July,  to  attack  trees  of  all  ages,  but  to  prefer  those 
10  to  15  years  old,  and  one-year-old  needles.  It  attacks  the 
Austrian  as  well  as  the  Scots  pine,  and  appears  to  have 
a  single  generation.  It  is  not  so  common  as  L.  j^in/,  and 
should  be  treated  similarly. 

The  larvae  of  various  species  of  Xcmatiis  (with  14  prolegs) 
and  Lyda  (2  prolegs)  also  attack  spruce,  larch,  and  pines. 
N.  ericksoni,  Hrtg.,  has  been  very  destructive  to  young  larch 
in  Cumberland  in  190G.  Its  larvae  may  be  recognised  by 
their  grey  colour,  with  a  darker  medium  zone.  N.  laricis, 
Hrtg.,  also  attacks  larch ;  its  larvae  are  green. 

*   Oj).  cit.,  page  25.J. 


WOOD-WASPS.  355 

Family  II. — Uroceridae  (Wood-wasps). 
Description  of  Family. 

Wood-Husps  have  straight  filiform  or  setaceous  antennae, 
always  shorter  than  the  body,  and  with  11  to  30  joints ;  3  large 
ocelli ;  body  long  and  cylindrical ;  wings  elongate  with  com- 
plete venation.  Legs  with  double  trochanter,  anterior  tibiae 
with  a  single  apical  spine.  Abdomen  sessile,  with  9  segments ; 
ovipositor  elongate,  projecting  beyond  the  end  of  the  abdomen, 
and  consisting  of  two  lateral  sheaths  and  a  strongly  serrate 
median  borer. 

Generation  lasting  at  least  two  years.  Larvae  cylindrical, 
soft,  and  whitish,  with  6  legs,  and  a  spine  at  the  rounded 
posterior  extremity.     Pupae  soft  and  white. 

The  larvae  live  chiefly  in  coniferous  wood,  in  which  the 
perfect  insects  lay  eggs  with  their  long  ovipositors.  Pupation 
also  takes  place  in  the  wood,  and  the  wood- wasp  emerges  by 
a  circular  hole. 

1.  Sirex  javencus,  L.  {Steel-blue  Wood-wasj)). 
a.  Description. 
The  insect  attains  a  length  of  12 — 30  mm.  ( S  )  and,  including 
ovipositor,  16 — 30  mm.  (  ?  ) ;  thorax  and  abdomen  steel-blue, 
the  latter  in  the  J  with  the  4th  to  the  7th  segment  inclusive, 
yellowish  red ;  in  $  the  steel-blue  ground-colour  of  the 
abdomen  is  iridescent,  with  a  coppery  sheen.  Wings 
yellowish,  with  brown  margins.  Legs  chiefly  reddish-yellow. 
Ovipositor  shorter  than  the  abdomen.  I.arva  up  to  30  mm. 
long,  with  G  very  small  feet,  white. 

b.  Life-ldstorij,  el^c. 

The  $  in  July  bores  the  bark  of  the  Scots  pine,  usually  of 
trees  in  pole-woods,  down  to  the  sapwood,  and  lays  an  egg  in 
each  hole.  The  larva  eats  out  in  the  wood  a  curved  burrow 
of  circular  section  ;  at  th'st  it  lives  in  the  softer  layers  of  the 
sapwood,  but  after  the  first  hibernation  it  bores  deeper  into 
the  tree,  living  on  the  resinous  and  starchy  matters  in  the 
burrow,  the  dust  of  which  it  packs  behind  it. 

After  a  second  hibernation,  in  the  early  summer  of  the  3rd 
year,  it  constructs  a  pupal  chamber  at  the  end  of  the  burrow, 

aa2 


.'356 


PROTECTION   ACJAINST   INSECTS. 


lining  it  with  a  glazed  coating.  The  uood-nasp  emerges  in 
July,  by  a  larval-gallery,  or  by  boring  for  itself  a  short  way 
through  the  wood.  The  flight-hole  is  circular  (being  thus 
distinguished  from  those  of  longicorn  beetles  that  are  oval),  and 


Fig.  185. — I'iue-wood  Ijuini  h\  lln.-  hmu  ui  >^nr.,  ju 
a  Larval  burrows  i)artly  filled  with  boriug-dust  $. 


iiriis,  L.     (^Xalitnil  size.') 
y  Circular  flight-hole. 


about  the  fourth  of  an  inch  in  diameter.  The  generation  lasts 
at  least  two  years,  and  sometimes  longer,  the  wasps  appearing 
from  wood  which  has  been  worked  up  for  some  time. 

In  Germany,  it  sometimes  attacks  spruce  as  well  as  Scots 
pine,  and  in  tlie  British  Isles*  it  has  been  observed  on  larch, 

*  Miss  Onacrod,  aji.  ctt  ,  [jage  2.VJ. 


WOOD- WASPS. 


357 


silver  fir,  and  other  conifers.  All  wood-wasps  prefer  weakly 
trees,  which  have  heen  injured  by  deer,  lightning,  or  wind, 
and  especially  trees  felled  in  the  growing  season  and  stripped 
of  bark.  They  never  attack 
actually  rotten  wood,  or  per- 
fectly sound  standing  trees. 
Miss  Ormerod  relates  an  in- 
stance where,  at  Workington, 
Cumberland,  in  1889,  1,700 
c.  feet  of  silver-fir  valued  at 
£'60  were  irretrievably  ruined. 
The  damage  done  is  economic, 
not  physiological. 


Fig.    186.— Wood- wasp    in    the    act    of 
boring,  exi)oso(l  by  splitting  the  wood. 


e.  Prolcctive  Eide-^. 
Removal  of  all  high  stumps  and  broken  wood.     Felling  of 
all  weakly  or  damaged  poles  and  trees  in  the  thinnings,  and 
rapid  removal  of  coniferous  timber  from  the  forest. 

2.  Sire.v  (jiifas,  L.   {Yellow  wood-a-asj)), 
a.  De-'irri/itio/i. 

/»(rt//o  20— 32  mm.  (J)  to  15  mm.  ($)  in  length;  black, 
head  with  a  large  yellow  spot  behind  the  eyes  ;  abdomen  (<?  ) 
reddish-yellow,  with  the  first  and  last  segments  black,  (  ?  ) 
black  with  the  2  anterior  and  3  posterior  segments  yellow  ; 
legs  black,  with  the  knees  yellow  ;  ovipositor  nearly  as  long 
as  the  body. 

Lan-d,  like  that  of  the  preceding  species. 


/>.  Lifv-}ii story,  e/c. 

This  species  is  particularly  attached  to  the  spruce,  but  is 
sometimes  found  in  silver  fir.  Its  habits  arc  tlic  same  as 
those  of  *S'.  jtivencns,  L. 

It  is  tolerably  frequent  in  Britain,  and  prefers  large 
trunks. 

The  treatment  of  its  attacks  is  similar  to  that  adopted  for 
S.  jiivcncits,  L. 


358  protp:cttoiV  against  in^^fx'I's. 

FA^rILY  III. — Cynipidae  (Gall-T\'asps).* 
Descrijytinn  of  Fainilj/. 

ImcKjos  with  straight,  filiform  antennae,  witli  13  to  16  joints; 
ocelli  far  back  on  the  crown  of  the  head.  Forewings  with  only 
6  to  8  cells,  with  no  stigma,  and  with  1  radial  and  2  to  3 
cubital  cells.  Some  species  have  no  wings,  or  only  abortive 
ones.  Abdomen  pedunculate,  laterally  compressed  and  trun- 
cate at  apex,  much  shorter  than  the  wings.  S  usually  very 
small.  Larvae  usually  thick  and  fleshy,  curved,  smooth,  white, 
and  apodal.  Pupae  thick-set,  smooth,  and  white.  They  are 
divided  into  3  groups  :  Tnie  GaU-irasps,  Secondari/  Gall-irasps, 
and  Parasites. 

1.   True  Gall-wasps. 

The  true  gall-wasps  bore  with  their  ovipositor  into  leaves, 
buds,  shoots,  fruits  and  other  parts  of  woody  plants,  and  they 
insert  one  or  more  eggs  in  the  wound.  The  egg  hatches  in 
due  time  and  the  larva  lives  in  a  chamber  formed  in  a  growth 
or  gall,  often  of  hard  or  woody  consistency,  formed  by  the  pro- 
liferation of  the  surrounding  plant-cells.  The  growth  of  this 
gall  is  not  due  to  the  irritation  caused  by  the  mother,  but  to 
the  stimulus  caused  by  the  internally-feeding  larva.  Galls 
may  be  on  roots,  bark,  buds,  leaves,  blossoms  or  fruits.  They 
may  also  contain  one  larval  chamber,  or  many,  the  former 
being  most  usual.  The  insect  usually  hibernates  in  tlie  gall, 
rarely  under  dead  leaves. 

The  oak  is  attacked  by  about  fifty  species  of  gall-wasp,  and 
galls  are  chiefly  found  on  badly-growing  underwood  in  coppice 
or  high  forest.  This  is  probably  due  to  the  fact  that  tannic 
acid  flows  into  the  gall  tissues,  which  are  thus  rendered 
immune  to  birds.  The  consequent  damage  is  not  serious,  as 
the  attack  is  chiefly  on  foliage.  At  the  same  time  galls  on 
buds  or  bark,  when  very  numerous  on  seedlings  or  coi)iHee- 
shoots,  may  cause  stunted  growth.  Some  species,  on  account 
of  the  tannic  or  gallic  acid  they  contain,  are  useful  in  producing 
the  galls  used  in  commerce. 

Probably  the  most  harmful  species  is  the  common  marble 

*  As  llio  fiiiiiily  (if  Dijilcin.  known  .-is  rrci(/iiiiii/iif/iir.ci>u\:\i]]-^  niiiiiy  species  < if 
gall-fics,  it  is  preferable  to  toriii  tiie  /'///lijiit/nr  i/ii!/-ir<i.y).\-. 


OALL-WASPS.  859 

gall- wasp  {Cyniiis  l^Uari,  Hart.),  which  sometimes  occurs  in 
large  numhers  on  young  oak  plants.  The  galls*  may  be  cut  off 
with  a  knife  while  they  are  still  young  and  soft,  and  if  thrown 
away  they  dry  and  shrivel,  and  the  maggots  within  perish. 
Titmice  are  very  useful  in  oak  nurseries,  as  they  pick  the 
maggots  out  of  the  galls. 

It  is  interesting  to  know  that  in  many  species  of  gall-flies, 
a  wingless,  hibernating,  parthenogenetic  generation  always 
alternates  with  a  winged  generation  of  both  sexes.  As  an 
example,  the  wingless  agamic  female  form,  Cijnips  aptera,  is 
hatched  from  galls  on  the  roots  of  the  oak,  and  hibernates  in 
the  soil,  laying  in  the  spring,  on  the  terminal  buds  of  the 
oak,  a  number  of  unfertilised  eggs.  These  cause  galls  on  the 
terminal  shoots  from  which  the  winged  forms  of  both  sexes, 
C.  terminalis,  Fabr.,  develop.  The  fertilised  ?  of  this  insect 
lays  her  eggs  on  the  roots  of  the  oak,  and  from  them  C.  aptera 
is  hatched  out,  and  so  forth,  f 

2.  Secondary  Gall-Wasps. 

These  are  also  termed  InquiUnes,  or  fellow -lodf/ers,  as  their 
$  lay  eggs  in  galls  made  l)y  the  true  gall-flies,  and  their  larvae 
are  either  parasitic  on  the  larvae  of  the  latter,  or  else  merely 
live  with  them  in  the  same  gall,  e.f/.,  Synergm  vulgaris,  Htg., 
lives  in  galls  of  Cynips  foUi,  L. 

3.  Parasitic  (kill-tcasps. 

The  ?  lay  their  eggs  in  other  insects  in  which  their  larvae 
are  parasitic,  and  thus  form  a  connecting  link  with  the 
Ichneumonidae,  e.g.,  Allotria  erythroeephala,  Hig. 

Parasitic  on  the  Rose  aphis. 

Hess  gives  a  summary  account  of  the  chief  species  of 
gall- wasps. 

*  Miss  Ormerod,  op.  rit.,  p.  2:57. 

t  Many  so-called  fjnUx,  or  malformations  of  plants,  are  caused  by  fungi  or 
bacteria  as  well  as  by  gall-wasps  and  gall-flics.  A  beautifully  illustrated  book 
on  "British  Vegetable  Galls,"  by  E.  T.  Connold,  was  published  in  1901,  by 
Hutchinson  &  Co.,  Paternoster  Row,  London,  and  the  author  is  now  preparing 
for  the  press  a  second  volume,  on  oak-galls  only. 


360 


PROTKCl'ION    AGAINST    INSECTS. 


B.  Diptera.  . 

Family  I. — Cecido.myiidae  (Gall-gnats). 

Flies  with  long  thread-like  or  moniliform  antennae,  with 
10  to  3G  joints,  usually  with 
whorls  of  hairs  ;  hody  delicate  ; 
wings  moderately  large  with 
rounded  anterior  border,  con- 
stricted at  the  base,  often 
iridescent,  with  3  to  5  longi- 
tudinal veins  ;  abdomen  cylin- 
drical, consisting  of  8  segments, 
in  ?  pointed  and  often  furnished 
with  a  projecting  tubular  ovi- 
positor ;  legs  slender,  the  tibiae 
unarmed  at  apex. 

Larvae  long  fusiform  legless 
maggots,  slightly  flattened,  with- 
out chitinous  mouth -armature, 
jjut  with  a  chitinous  fork  or 
"  anchor-piece  "  eml)edded  in 
the  skin  of  the  ventral  surface; 
usually  pale  yellowish  or  reddish. 
The  iiiiagos  lay  their  eggs  in 
needles,  leaves  or  bark,  in 
which  the  young  larvae  feed  by 
sucking,  and  thereby  cause  gall- 
like swellings. 

Fie.    187.— Larch   twier,   with   trails  ,,  , 

made  by  c.  Mneri,  Suschl.  '  ^^veral  species  are  common 

iNaiural  she.)  On  willoWS. 

1.  Cecidomyia  salicij^erda,  Duf.  {Willoir  GaU-fiuat). 
(I.   Deficrijilidn. 
i'V// 2  to  8  mm.  long;  black-brown;  the  wings  milky-white 
with  whitish  hairs ;  antennae  shorter  than  tiic  body. 
Larva  yellowish  red. 

//.   Life-ltislorji,  dr. 
The  eggs  are  laid  during  i\[ay  in  rows  on  the  Itark  of  the 
branches  up  to  the  thickness  of  one's  arm  of  pollard-willows 


CHHRMES    ABIETIS.  361 

and  on  4-  to  8-  year-old  shoots  of  willows.  Salix  iriamlm, 
L.,  S.  fragilis,  L.,  and  S.  alba,  are  all  attacked.  The 
maggot  bores  horizontally  through  the  bark,  in  which 
from  July  to  the  following  April  it  excavates  short  irregular 
vertical  galleries.  This  causes  the  appearance  of  spindle- 
shaped  swellings  of  the  bark  and  underlying  wood,  at  least  in 
the  larger  stems,  which  eventually  become  rough  owing  to  the 
irregular  detachment  of  the  bark.  Pupation  takes  place  in 
the  same  spots,  and  the  emergence  of  the  flies  riddles  the  bark 
with  small  holes. 

This  species  is  sometimes  decidedly  common  and  injurious 
to  planted  willow  cuttings.  The  only  satisfactory  treatment 
is  the  timely  cutting-off  and  burning  of  the  infested  shoots 
before  emergence  of  the  gnats. 

The  family  of  CeridomijikJac  also  contains  the  Hessian-fly, 
C.  destructor,  Say,  one  of  the  greatest  of  pests  to  cereal  crops, 
and  various  species  attacking  conifers,  of  which  C.  kellneri, 
Hnsche.,  gives  rise  to  galls  on  the  buds  of  larch.  Others  pro- 
duce galls  on  beech  leaves  {C.fagi,  Htg.),  and  on  l)irch  leaves 
C.  hHidae,  Wtg. 


C.  Hemiptera. 

Family  I. — Aphididae  (Plant-lick). 

Description  of  Family. 

Insects  with  long,  usually  filiform  or  setose  antennae,  of  3  to  7 
joints;  ocelli  either  absent  or  3  in  number;  rostrum  usually 
well  developed.  Wings  membranous,  often  absent,  especially 
in  2  .  Legs  usually  long  and  thin  ;  tarsi  of  2  joints.  They 
move  by  flying,  or  running. 

The  species  of  Chermes  comprise  those  aphides,  that  are  of 
most  importance  as  being  injurious  to  forest-trees,  especially 
to  coniferae. 

The  mode  of  life  of  plant-lice  is  as  follows  :  The  hard- 
shelled  eggs  that  resist  the  cold  are  laid  during  autumn  in 
rows  or  groups  on  needles,  leaves,  buds  or  shoots,  and  hiber- 
nate. In  the  spring,  small  wingless  ?  producing  parthenogenetic 
wingless  ?  issue  from  the  eggs,  and  thus  several  generations 


863 


PROTKf'riOX    ArJATNST    INSECTS. 


^A^.'^ 


^( 


arise  of  partheiiogenetic  insects.  The  last  generation  in 
autumn  is  winged  and  produces  3  and  $  ;  from  the  latter 
eggs  are  produced  and  hibernate.  Besides  this  dimorphism, 
in  the  genus  Clicrmes  the  insects  migrate  from  one  species  of 
plant  to  another  in  order  to  change  their  food.  By  piercing 
plants  or  sucking  them,  they  produce  galls  and  other  mal- 
formations, on  leaves,  needles,  buds, 
flowers,  etc.,  especially  on  broad- 
leaved  plants.  Most  species  are 
monophagous,  almost  every  species 
of  plant  having  its  peculiar  plant- 
lice.  Most  plant-lice  produce  houcij- 
doir  from  leaves,  this  being  their 
excrement. 

In  Clicrmes,  there  are  three 
different  images  :  winged  partheno- 
genetic  $  ,  wingless  parthenogenetic 
?  ,  and  wingless  sexual  imagos  of 
both  sexes. 

The  wingless  parthenogenetic  2  , 
stem-mother  ov  fundatrix,  hibernates 
alone  on  spruce  buds.  After  three 
moultings  in  the  spring,  she  sucks 
the  opening  buds,  lays  a  number  of 
eggs  and  dies  near  them.  The 
sucking  of  the  mother  causes  a  gall 
to  form,  and  from  the  eggs,  very 
shortly,  wingless  lice  arise,  which 
force  their  way  deeper  into  the 
increases  in  size,  chambers  being 
The  latter,  after  3  moultings,  acquire 
rudimentary  wings,  and,  opening  the  gall-covering,  come  out 
as  lupnphs  on  the  needles.  After  another  moulting  they 
acquire  wings. 

Then  some  of  the  winged  lice  remain  on  the  tree,  and  lay 
eggs  from  which  the  hibernating  parthenogenetic  J'undatiix 
arises.  She  continues  to  act  as  already  descri])ed  and  corre- 
sponding broods  arise  for  several  years. 

The  other  winged  lice    leave  the  spruce  for  other  conifers. 


Fig.  188.— Gall 
ahielis,  L.,  oil  a 
(^Natural  size.) 


gall,    which    therefore 
formed  round  the  lice. 


CHERMES    ARTETT8.  363 

silver  fir,  larch,  or  pines,  and  lay  eggs  from  which  wingless 
lice  arise  that  winter  on  the  tree  and  lay  eggs  next  spring. 

From  these  eggs  some  of  the  nymphs  eventually  become 
winged  lice  that  fly  back  to  the  spruce  and  lay  eggs 
there  from  which  <?  and  ?  arise.  The  other  wingless 
parthenogenetic   2  continue  their  life  on  the  other  trees. 

1.  Cltermcs  ahietis,  L.  {Spruce-gall  ApJiis). 
a.  Descriptmi. 
Wiuf/leas   stem-mother,   yellowish-green,   becoming  darker 
when   full-grown.      Body   covered   with    white   wool.      Gall- 
dwellers  bright  yellow. 

Winricd  lice,  2 — 2*4  mm.  long,  with  dark  head  and  back  and 
yellow  undersurface.     Sexual  insects  bright  yellow. 

b.  Relalionfi    In   the   Forest. 

The  galls  (in  size  from  that  of  a  cherry  to  that  of  a  walnut) 
which  result  from  their  injury  are  at  first  soft  and  green, 
becoming  later  purplish-red  in  places  and  finally,  when  hard 
and  dry,  brown.  They  contain  a  quantity  of  tannin.  Their 
size  is  characteristic,  as  is  the  fact  that  they  are  topped 
with  a  sprig  of  needles,  as  long  as,  or  longer  than,  the  gall. 
This  is  the  stunted  young  shoot.  The  injured  shoots  take  on 
a  characteristic  curvature  towards  the  side  on  which  the  gall 
is  growing.     The  loss  of  growth  may  be  consideral)le. 

The  other  hosts  of  this  insect  are  larch,  Scots  pine,  Cembran 
pine,  and  in  Russia,  the  Siberian  spruce. 

The  spruce-gall  aphis  is  common  both  in  plains  and  in  hilly 
country,  and  attacks  young  spruces  especially  in  nurseries  and 
those  which  have  been  injured  by  frost  or  animals.  It  is  also 
common  on  the  border-trees  of  10-  to  20-  year-old  plantations. 
Fortunately  the  attack  is  usually  confined  to  the  side-shoots, 
and  the  leading  shoot  escapes. 

c.  Uemcilial  ileaniires. 
Protection  of  the  smaller  insectivorous  birds :  tits,  the  nut- 
hatch and  golden-crested  wren.     A  spider  (llicridion)  is  an 
active  destroyer  of  this  insect,  spinning  its  web  over  the  galls 
and  preventing  the  escape  of  its  inmates.     Direct  treatment  is 


364. 


PROTECTION   ArJAINST   INSECTS^. 


trouljlesome  ;  the  galls  if  on  seedlings  ma}'  be  snipped  off,  and 
the  experiment  may  l)e  tried  of  spraying  the  young  trees  in 
April  with  kerosene-emulsion.     (See  the  following  species.) 


2.  Chcnncs  coccincns,  Etzb, 

The  winged  ?  ,  1*6  mm.  long,  are  dark  red.    The  galls  formed 

on  the  spruce  by  this  insect  are  at  first  yellowish  green,  then 

red,  and  lastly  brown,  but  are  much  smaller  than  those  of 

C.  ahietis,  L.     They  are  also  always  on  side-shoots,  and  are 

never   topped    by  a  sprig  of    needles. 

Isolated  and  border  plants  are  usually 

selected. 

The  intermediate  hosts  are  the 
common  silver-fir  and  other  firs.  The 
winged  emigrants  lay  their  reddish- 
yellow  eggs  below  the  needles  of  firs. 
The  brown,  later  blackish,  wingless 
plant-lice,  w^hich  come  from  these  eggs 
in  2 — 3  weeks,  suck  the  needles  and 
lay  yellowish  or  reddish-brown  eggs 
covered  with  wool,  that  hibernate. 
These  give  rise  to  other  wingless 
plant-lice  in  the  spring,  on  the  young 
twigs,  from  the  eggs  of  which  are  pro- 
duced winged  and  wingless  ?  .  The 
former  fly  back  to  the  spruce  and  the 
others  remain  on  the  silver-fir.  From  eggs  laid  by  the  former 
the  S  and  $  arise. 

Those  that  remain  on  the  silver-fir  cover  the  bark,  which 
looks  as  if  it  had  been  powdered.  Damp  places  .sheltered 
from  the  wind  are  preferred.  Young  silver-fir  may  be  seriously 
weakened  l)y  this  attack,  which  is  very  destructive  to  silver-fir 
in  Scotland.  Abies  f/randis,  Lindl.,  is  said  to  escape  injury. 
Remedial  measures  as  for  C.  ahietis,  L. 


Fig.  189.— Gall  of  C.  coc- 
cincns, Rt/.l).  {Xatiiral 
size.') 


3.  Chermes  strohiloJiim^,  Kll)). 
Galls  on  the  spruce,  intermediate  in  size  l)etwecn  those  of 
C.  ahielis  and  C.  coceincus.     It  looks  like  an  unripe  strawberry, 
with,  or  without,  a  sprig  of  needles  at  top. 


CHEllMES    STROBILOBIUS. 


365 


The  larch  is  the  intermediate  host  of  this  insect,  and  the 
phmt-lice  on  the  larch  were  formerly 
known  as  Chermes  hiricis,  Hart,  (the 
larch  aphis). 


a.  JJescrijilioii. 

Imago  ?  ,  rather  smaller  than  the 
preceding,  hlackish  -  bro^Yn,  covered 
with  a  white  woolly  down  ;  the 
winged  form  dirty  green,  or  with 
the  head  and  thorax  reddish-brown. 
No  male  is  known. 

h.  Lifc-HhUniJ. 
The  wingless  females  pass  the 
winter  on  the  larch,  like  those  of 
C.  ahictis,  Hart.  They  lay  their  eggs 
and  from  April  to  August  the  aphides 
sit  and  feed  on  the  needles,  which 
become  discoloured  and  acquire  a 
peculiar  elbowed  shape.  No  gall  is 
formed.  They  acquire  wings  in 
August  and  disperse  to  other  larches, 
or  to  the  spruce.  When  they  are 
look  as  if    they  had    been    sprinkled 


V\'^.  I'JO.  —  Larch  -  shoot 
attacked  by  Chermtn  hiricin, 
Hart.     {Xtilund  size') 

a  Insects  I'ceiliui,'  ou  the 
needles,  which  show  a 
characteristic  auyular  bend. 

abundant,  the   larches 
with  snow. 


r.  Troalmcnf. 

Spraying  with  kerosene-emulsions,  soft-soap,  limewater  or 
weak  solutions  of  corrosive  sublimate.  Keep  spruce  away  from 
larch  nurseries. 

4.  Chcnut'H  sibiricus,  Clioldk. 

The  winged  females  greatly  resemble  those  of  C.  coccineiis, 
lUzb.,  and  C.  strubilobius,  Ktlb. 

The  galls,  3-10  cm.  long,  consist  of  a  but  slightly  altered 
bent  twig,  the  needles  on  the  inside  of  which  become  thick 
and  woody,  but  not  coalescing  as  in  the 'former  galls.  The 
dark  red  plant-lice  eventually  produce  winged  offspring  that 
fly  to  the  Hcots,  Weymouth  or  Cembran  pines,  and  these  lay 
reddish-yellow  eggs.     Those  that  stay  on  the  pines,  formerly 


3G6  TROTECTION    AGAINST    INSECTS. 

termed  Chcrmes  strohi,  Htg.,  attack  plants  from  live  years  old 
and  mature  trees.     Young  plants  become  greatly  weakened  by 
these  attacks,  and  many  Weymouth  pines  have  thus  been  killed 
in  the  Woburn  Woods,  Bedfordshire. 
Kemedial  measures,  as  before. 

Family  IL — Coccidae  (Scale-insects). 
Desrrijitioii  of  Fiunilij. 

Very  minute  insects  with  moniliform  antennae,  of  (J  to  25 
joints ;  rostrum  rudimentary  in  the  3  .  3  with  2  or  4  mem- 
branous wings  without  cells  ;  ?  ,  except  one  apterous  species, 
Aleurodes  chalidonii,  Latr.,  swollen,  more  or  less  shield-shaped  ; 
one  tarsal  joint.  The  2  burrow  their  beak  deep  into  the  plant- 
tissues  and  swell  up  into  spherical  bodies,  and  in  May  and 
June  lay  numerous  eggs  on  plants,  and  die  on  the  eggs.  The 
eggs  hatch  into  3  and  ?  larvae  that  pupate  in  autumn  or  spring. 
Single  generation. 

The  imagos  and  larvae,  under  the  protection  of  shields  or 
2)iiparia,  partly  composed  of  fibrous  secretion,  partly  of  the 
cast-oif  exuviae,  suck  the  young  shoots,  leaves,  bark,  etc.  of 
perfectly  sound  plants,  and  cause  blistering  and  disease  in  the 
organs  which  they  have  attacked.  In  this  way,  beech,  spruce, 
oak,  ash,  robinia,  and  other  plants  may  be  attacked  by  different 
species. 

The  most  eliective  treatment  known  for  nursery  plants  so 
attacked  is  to  wash  them  wdtli  limewater  in  the  spring,  or  cut 
off  and  burn  infected  twigs.  The  plants  may  also  be  treated, 
when  practicable,  with  paraffin  emulsion  or  washes  made  by 
forming  a  soap  with  boiling  water,  resin  and  potash.  The 
scales  may  also  be  scraped  off  with  a  blunt  knife,  or  rough 
brush,  and  the  plants  smeared  with  soft-soap  and  water.* 
When  scale  appears  on  coppice-shoots  or  saplings,  cut  and 
burn  the  atTected  plants. 

1.  Coccus  fcKji,  Biirensp.  {Scale -felt,  or  Beech  icoolli/  apliis). 
Hitherto  only  the  ?  is  known.     This  is  a  very  small,  pale- 
yellow,  legless,  apterous  scale-insect,  measuring  about  ./•,  inch 

*  For  apple-scale  Miss  Ornicro<l  reconiniciuls  i'  lbs.  soft  soap,   I   lb.  flowers  of 
sulphur,  14  gallous  of  water. 


SCALE-FELT,    OR    IJEECII    WOOLLY    APHl.S.  367 

ill  length,  it  is  lens-shaped,  being  fiattish  below  and  highly 
convex  above.  The  mouth  is  on  the  underside  of  the  body, 
and  composed  of  three  hair-like  appendages,  united  to  form  a 
long  sucking  tube  ;  with  it  this  insect  pierces  the  bark  and 
sucks  the  sap.  She  has  no  power  of  locomotion.  Almost 
immediately  after  leaving  the  egg,  she  covers  her  body  with  a 
white,  felted,  waxy  secretion,  which  forms  an  excellent  coat, 
impervious  to  rain.  Within  this  coat,  she  lives,  lays  her  eggs 
and  dies. 

The  larvae  are  very  tiny  and  active,  and  scarcely  visible  to 
the  naked  eye.  They  possess  three  pairs  of  legs  and  a  pair  of 
antennae,  and  like  their  parent  are  yellow.  They  can  move 
over  the  bark  of  the  tree,  but  usually  settle  down  under  the 
body  of  their  dying  or  dead  parent,  preferring  the  deepest 
parts  of  the  bark-fissures,  where  they  remain  sucking  the  sap. 
Each  larva  protects  its  body  with  wool,  which  is  added  to  that 
produced  by  previous  generations.  The  secretion  therefore 
gradually  thickens  and  spreads  over  the  tree-trunk,  forming  a 
more  or  less  continuous  mass.  Larvae  wandering  over  the 
bark  are  borne  by  the  wind  or  by  birds  or  insects  to  other 
trees  and  spread  the  infection.  The  larvae  hibernate, 
and  eventually  lose  their  legs  and  antennae  and  become 
parthenogenetic  ?  . 

Young  and  old  beech  trees  are  attacked,  the  sheltered  side  of 
exposed  trees  being  selected.  The  attack  sometimes  lasts  for 
years  without  apparent  injury  to  the  tree,  while  others  die,  the 
foliage  gradually  becoming  discoloured  and  thin  and  the  smaller 
branches  dying,  the  bark  peeling  off  the  branches  and  trunk. 

In  the  extensive  beech  forests  near  Brussels,  the  absence  of 
thinning  is  said  to  favour  the  disease,  and  where  thinnings  are 
made  it  is  generally  absent.  It  is  extremely  rare  in  the  beech 
woods  of  the  Chiltern  Hills,  which  are  usually  over-thinned. 

Remedial  measures.     As  given  above. 

2.  Lecaniam  hemicryphum,  Dalm. 
Lecanium  differs  from  Coccus  by  the  ?  swelling  up  over  the 
eggs  and  its  back  being  chitinised  to  form  the  scale.    This  scale- 
insect  and  the  accompanying  fungus,  Apiosporium  pinopJii/llum, 
Tuckel.,  nourished  by  the  honeydew,  cause  a  black,  paste-like 


368 


PROTECTION    AGAINST   INSECTS. 


coating  on  branches  and  twigs  of  5-  to  15-  years-old  spruce, 
which  makes  them  languish  for 
several  years.  It  has  done  much 
damage  to  spruce  plantations  in 
Saxony,  and  near  Tharand  was  found 
on  mature  spruce,  which  had  been 
injured  by  locomotive  smoke.  This 
insect  is  attacked  by  a  parasitic  weevil 
{Biachytarsuii  varius,  Fabr.).  Lcca- 
niiLiii  fraxini,  Sign.,  attacks  ash. 

Another  injurious  genus  of  scale- 
insects  is  Aspidiotits,  in  which  the  ? 
live  under  a  coat  formed  of  larval 
skins  and  a  waxy  scale,  the  <?  under  a 
smaller  waxy  scale  and  one  larval  skin. 
Aspidiotus  sidicis,  L.,  attacks  pop- 
lars, willows  and  ash,  and  frequently 
kills  black  poplar.  When  crushed,  a 
blood-red  fluid  exudes  from  the  insects. 

This  species  greatly  impairs  the  growth  of  young  ash. 


w 


Fig.    191. 


Spruce  -  shoot 
attacked  by  Lccan'tiim  ht-mi- 
cryphum,  Dalm.   '{Natural 
size.) 
a  Feeding  scale-insects. 


D.  Orthoptera. 
Family  I. — Geyllidae  (Crickets). 
Dei<criiiik)ii  of  Familij. 
The  insects  of  this  family  possess  a  thick,  free  head,  with 
long  bristly  antennae  of  many  joints,  and  2  or  3  ocelli ;  hind- 
wings  folded  longitudinally,  and  projecting  beyond  the  wing- 
cases,  but  often  aborted,  or  absent,  not  roof-shaped  in  repose. 
Body    cylindrical;    fore-legs    formed    for    burrowing;    tarsi 
3-jointed.     Ovipositor  long,  sometimes  absent.     The  species 
produce  a  chirping  noise  by  rubbing  the  wing-cases  together. 

They  dig  holes  in  the  ground,  and  live  partly  on  larvae  and 
worms,  partly  on  the  roots,  seeds  and  fruit  of  forest  plants,  or 
on  grass  and  herbage. 


1.  G ri/Uoialjxi  ri(J(ia>iti,  Latr.  {Coiiiiikui  Molf-crickct). 
a.  /Jcscrijdion. 
Imago  35  to  45  mm.  long,  reddisli-l)rown  or  dark  brown,  and 
lighter  beneath ;  the  wing-cases  short  willi  black  veins,  not 


MOLE-CRICKET. 


369 


covering  the  wings ;  abdomen  with  two  caudal  processes. 
Fore-legs  sturdy,  resembling  hands,  used  for  burrowing,  like 
those  of  the  mole.  The  larva  and  nijmpJi  greatly  resemble 
the  perfect  insect  in  form  and  colour,  but  have  the  wings 
undeveloped.  ^^ 

b.  Life-Jiistory. 

Pairing  takes  place  under- 
ground, from  the  beginning 
of  June  till  the  middle  of 
July. 

The  ?  during  the  month 
of  June  lays  150  to  250 
pale  yellowish  eggs,  as 
large  as  hempseed,  in  a 
hole  of  the  size  of  a  hen's 
egg,  and  about  10  to  12  cm. 
below  the  surface  of  the 
ground,  with  which  it 
communicates  by  a  tunnel 
or  shaft,  with  a  circular 
section. 

The  earth  above  and 
around  the  hole  is  rendered 
more  compact  by  the  saliva 
of  the  $  .  The  ?  watches 
the  nest  carefully,  and  when 
disturbed  returns  to  it  by 
the  tunnel. 

The  young  larvae  appear  after  2  to  3  weeks,  and  remain  3  to  4 
weeks  in  the  nest ;  they  then  begin  to  burrow  in  the  ground, 
moult  3  times  before  October  or  November,  and  then  hibernate 
in  the  ground. 

The  nymph-stage  takes  place  at  the  end  of  May  or 
beginning  of  June  with  the  fourth  moulting,  the  nymph 
being  active  and  feeding;  with  the  last  moult,  instead  of 
the  little  lappets  which  represent  the  wings  in  the  nymph, 
4  true  wings  appear,  and  the  form  of  the  perfect  insect  is 
assumed. 


The   mole-cricket,  GnjUotnlpa 
nih/aris,  L. 


Perfect  insect. 


h  and 

sta_^es. 


Larvae  in  early 


870  HHOTKC'I'ION    AriATNST    IN.SKCTS. 

Gcnrrathm  annual,  but  occasionally  the  larvae  may  persist 
over  another  year. 

c.  Relatione  to  the  Forest. 
The  msect,  in  all  its  stages,  damages  forest  plants.  It  bites 
through  the  roots  of  young  conifers,  especially  of  spruce  and 
Scots  pine,  when  1  and  2  years  old,  while  making  its 
burrows,  which  are  about  a  finger's  width.  It  also  uplifts 
young  plants,  which  fall  over  and  die.  The  mole-cricket  also 
bites  off  the  germinating  shoots  of  oak  and  beech  before  they 
reach  the  surface  of  the  ground,  and  the  roots  of  young  broad- 
leaved  seedlings,  tearing  the  latter  with  its  fore-legs. 


Fig.  193. — Xest  and  eggs  of  the  mole-cricket. 

On  the  other  hand  the  mole-cricket  is  useful  l)y  destroying 
numbers  of  underground  grubs.  The  ?  has  been  observed  to 
eat  some  of  her  own  brood. 

Favourite  localities  for  this  insect  are  loose  level  sandy 
soils,  free  from  vegetation,  but  it  is  also  found  on  clay  lands. 
Thinly  stocked  beds  of  seedlings  are  preferred  to  densely 
stocked  beds,  and  patches  to  lines  of  seedlings. 

The  mole-cricket  also  cuts  through  the  roots  of  agricultural 
crops.  It  is  not  yet  decided  whether  it  damages  plants  for  its 
own  nourishment,  or  to  clear  the  way  for  its  burrows. 

The  mole-cricket  is  only  local  in  JEngland,  and  does  not 
occur  in  the  north.  It  is  perhaps  commoner  than  is  generally 
supposed,  as  owing  to  its  underground  habits  it  is  seldom  seen. 


MOLE-CRICKET    AND    LOCUSTS.  371 

d.  Protertivp  Rulnft. 

i.  Isolation  of  seed  beds  by  trenches  25  to  30  cm.  deep  and 
wide ;  if  flower-pots  or  vessels  with  smooth  sides  be  placed 
with  their  tops  level  with  the  bases  of  these  traps,  many 
crickets  will  be  caught  and  may  be  destroyed. 

ii.  Protection  of  enemies.  Mole,  shrew-mice,  crow,  starling, 
etc.  The  larvae  of  ground  and  rove-beetles  also  attack  mole- 
crickets. 

e.  Remedial  Measures. 

i.  Destruction  of  nests  in  June  and  July.  They  may  be 
discovered  from  the  circular  orifice  in  the  ground  which  leads 
down  to  them,  and  by  the  wilting  plants  which  may  be  near 
them.  They  are  dug  out,  and  trampling,  pouring  hot  water 
over  them,  or  exposure  to  the  sun  will  kill  the  brood. 

ii.  Destruction  of  the  full-grown  crickets  in  June.  Great 
caution  must  be  exercised,  as  the  creatures  are  very  shy. 
Just  after  dusk,  the  worker,  who  should  l)e  barefooted,  ap- 
proaches cautiously  the  places  whence  the  chirping  arises,  and 
exposes  the  concealed  cricket  by  a  stroke  of  the  spade.  When 
seized  the  insect  emits  a  thick  black  excrement. 

iii.  Ordinary  flower-pots,  2  yards  apart,  may  be  placed  in 
nursery-beds,  so  that  the  crickets  may  fall  in  during  their 
nocturnal  rambles.  This  method  is  most  efiectual  at  pairing- 
time. 

iv.  Pour  petrol,  or  tar  and  turpentine  in  equal  parts,  into 
the  holes,  and  then  water  till  the  holes  are  full,  in  order  to 
drive  out  the  crickets.  At  Seligstadt,  100,000  crickets  were 
thus  destroyed  between  June  and  August,  1897. 

Family  II. — Acridiidae  {Loriists). 
lJesiri/)/io/i  of  FaiiiUy. 
Insects  with  vertical  heads,  the  antennae  shorter  than  the 
body,  with  not  more  than  25  joints  ;  wings  roof-shaped  in 
repose,  the  fore-wings  narrow  ;  body  laterally  compressed  ; 
tarsi  with  3  joints,  usually  with  a  lappet  between  the  claws  ; 
abdomen  with  an  auditory  organ  on  each  side  of  the  first 
segment,  ovipositor  short. 

B  B  2 


372  PROTECTION    AOATXST    INSECTS. 

Locusts  are  plant-eaters,  and  feed  cliiefly  on  the  produce  of 
fields  and  meadows,  but  also  on  the  foliage  of  l)roadleaved 
trees  and  shrubs,  especially  when  they  come  in  swarms,  and 
they  can  then  be  extremely  hurtful. 

The  commonest  European  species  is  rarJii/ti/Jiis  miriratorius, 
L.,  and  its  area  of  sub-permanent  distribution  is  from  lat.  40'^  N. 
in  Portugal  to  48'^  in  France  and  Switzerland,  and  rising  east- 
wards to  56"^  in  Piussia,  Siberia,  N.  Japan.  Its  area  of  occa- 
sional distribution  is  wider,  and  it  has  visited  England  and 
Scandinavia.  It  is  also  found  in  S.  latitudes  in  New  Zealand 
and  Austraha,  and  in  Mauritius  and  Africa.  Only  an  occasional 
visitor  to  India. 

Acrijdinm  j)ere(jrimnn  is  permanent  in  Africa  and  tropical 
Asia,  especially  India,  and  occasionally  visits  the  South  of 
Europe,  and  in  1869,  was  found  over  a  large  part  of  England. 

1.  Vachiitulns  migratorius,  L.  {JMif/ratonj  Locust). 
a.  Descrijifion. 

ImcKjo  35  to  48  mm,  long  {3),  42  to  55  mm.  long  (?), 
coloured  greenish,  or  brownish;  pronotum  produced  into  a 
blunt  point  in  front ;  wings  yellowish,  or  pale  brown,  almost 
transparent,  sliglitly  darker  at  the  tips ;  chest  with  white 
hairs  ;  hind  femora  bluish  on  their  inner  side,  with  a  black 
ring  in  front  of  the  joint ;  hind  tibiae  yellow. 

Larva  with  broad  brown  bands  on  the  front  part  of  the 
back,  and  wingless  until  it  has  moulted  four  limes. 

/'.  Lifi'-liislorij. 

The  eggs  are  laid  in  the  ground  3  to  4  cm.  deep,  in  groups 
of  70  to  80,  and  as  the  $  die  immediately  after  laying,  their 
dead  bodies  lying  on  the  ground  show  where  eggs  have  been 
laid. 

c.  Be/a/iotis  (o  Ihe  Forest. 

Locusts  devour  chiefly  agricultural  produce,  sometimes 
appearing  in  such  countless  swarms  as  to  leave  nothing  green 
over  many  square  miles  of  country.  South  Russia,  with  its 
extended  grain-i)roducing  plains,  is  specially  liable  to  this 
scourge,  and  so  is  Hungary.     Its  permanent  home  appears  to 


MKillATORY    LOCUSTS.  373 

be  the  barren  steppes  of  Central  Asia.  It  occasionally  spreads 
\^•est^Yards  over  Germany  and  as  far  as  Belgium,  and  even  into 
the  British  Isles.  While,  however,  devouring  chiefly  agricul- 
tural crops,  the  locust  does  not  spare  the  young  leaves  and 
terminal  buds  of  broadleaved  trees,  though  it  but  rarely 
strips  ofl'  all  the  foliage  of  a  forest.  In  1880,  in  Istria,  chiefly 
oak  and  ash  were  attacked  l)y  it,  other  broadleaved  trees 
being  spared.     Vineyards  were  also  attacked. 

(/.  Protective  Rules. 

i.  Destruction  of  eggs.  Very  difficult  to  carry  out  on  a 
large  scale. 

ii.  Destruction  of  larvae — which  is  the  best  method. 

They  have  been  exterminated  in  Cyprus  by  an  organised 
system  of  digging  trenches,  into  which  the  larvae  are  driven  ; 
strips  of  cloth  on  stakes  lead  up  to  the  trenches,  and  the 
locusts  are  crushed  by  thousands  when  the  trenches  are  nearly 
full,  and  then  fresh  trenches  are  dug.  In  South  Africa,  the 
larvae,  which  may  accumulate  in  masses,  are  killed  by  spraying 
with  coarse  blue  soap  and  water.  The  soap  blocks  up  their 
tracheae  and  kills  them  readily. 

iii.  Destruction  of  the  full-grown  locusts  may  be  effected 
during  wet  weather,  when  they  fly  with  difficulty. 


LIST   OF   DESTEUCTIVE   INSECTS. 

A  list  is  here  given  of  all  the  destructive  insects  dealt  with 
in  this  book,  arranged  according  to  the  species  of  tree  attacked 
and  the  different  organs  of  it  which  suffer. 

The  following  details  are  given  in  the  list : — 

Organs  of  tree  attacked  :  root,  bark,  cambium,  wood,  buds, 
young  shoots,  needles,  leaves,  blossoms,  fruits  and  seeds. 

Stage  of  the  insect  at  the  time  when  it  is  injurious:  larva, 
imago;  or  sometimes,  in  the  case  of  Orthoptcra,  or  llcmiptera, 
all  stages,  including  the  nymph  or  pupa. 

Grade  of  injuriousness  of  insect. 

Age  of  woods  attacked  :  seedlings,  young  plants,  poles,  or 
trees. 

Characteristics  of  attack,  which  serve  to  indicate  the  offender. 


374 


PROTECTION   AflAINST   INSFXTS. 


The  following;  abbreviations  are  used 


J.    Imago. 
L.  Larva. 
A.  All  stages. 
(V.G.)   A'citical  gallery. 
(F.G.)   Forked 
(H.G.)  Horizontal    ,. 
(li.O.)    La(kl(;r  ,.      :  the  charac- 

teristic form  of  Trypodendrnn. 
(S.G.)    Stellate  gallery. 
S.  Hcedling. 


(V.r.)  Young  iilant>. 

P.  Poles. 

T.  Trees. 

*     Highly  injurious. 

O  Slightly    '    ., 

Insects  not  marked  with  cither  of  tlie 

above  signs aic  moderately  injurious. 

Those  with  the  mark  \  placed  after 

them     rarely    occur    in     the    case 

referred  to. 


1.   THE    SPEUCE. 


TiO0i> 


Wood. 


JJiiIiijihis  iiuirg'nuiiuit.   L.  (Y.P.)  214 

*firyll(iftilj)a  ridgarix.     A.  S. ...  3(>'J 

*Meli>h>nthit  lulgaris.    L.    2  to  3  . 

summers.     (Y.P.)     200 

*  M.  liijij>(irn.itam.     Id 20!) 

XorfiKt  segdum.     L.  S 325 

r>A]JK. 

*II,jloh;v.'<„hH'th.     I.  (Y.P.)  ...  22.-, 

*n.  j>itM.ifri.      Id 232 

Pi.s-wdp>i  >iof,iti/s.     Id.t    2.33 

J>.  phii .     1 .  ( Y.  P.  &  P.) 235 

P.hercyn'iae.     I.  T 235 

Strophosonni.t  roryli.    I.    (Y.P.)  22(» 

S.  olcxi/x.     Id 220 

Cambium. 
IFglasfcx   paUintiist.      I.    <k    L. 

'(V.G.)  (P.  k  T.) 2r,2 

JJyrlop/iiliis  pi/iijirrdd.     I.  k  L. 

(V.G.)T.t 205 

M.  minor.      I.  i:  L.  (H.G.)  (P. 

&  T.)t 271 

PhxodcM/iofafiiK  L.(Y.P.&P.).t  233 

P.phii.     Id 235 

P.  herryniue.     L.  T 235 

*T(iminis  iypogntphux.     I.  &  L. 

(V.G.)T 238 

*T.(tmithiux.     I.  &  L.  (K.(;.)  & 

(S.G.)T 21(1 

0  7'.    hidentaius.        (Y.P.   k    P.) 

(«.G.).t  253 

*T.  r/ialr(ig7-/ij)/iii.s.        1.     i<c     L. 

(S.G.)*P.  &T 248 

OT.stcnogmphvs.  I.A:  L.  (L.G.).t  250 
T.   Iriri'cis.       I.    k    L.     (V.G.) 
J'.^T 251 


Jfylrcoefun  dcnueslu'idcx.  I.A;L.T.  210 

Sire.f  jiirrnciix.     L.  T.f   355 

S.  gigux.     L.  ( P.  &  T.) 357 

*Tiii>iiriix    linrntiix.        I.    it     L. 

(L.G.)  (P.  ct  T.)    255 

Buds. 
"Lipiirix  momrhn.     L.  (P.  A:  T.)  310 

YouN(;  Shoots. 
Chrniicx  abirfix.     A.  (P.  &  T.) 

Large  galls 301 

*//yIohi„x  uhicflx.     L.  (Y.P.)  ...  225 
Lecdnivm      licniicryph  inn.      A. 
(Y.P.i^cP.) .' 367 

Needi.es. 

Gromrtra p'iniiivhi.  L.(P.i:T.)t  320 
Lrni  niinn     hciiiicryjihiim.       A. 

(Y.P.  iV:  P.)    ....'. 307 

*Lipiirix  tiiiindclut.     L.     Trees  of 

all  ages    310 

O  Mchdontha  spp.      I.  (1'.  A:  T.)...  200 

Aortiia  pinijwrdd.  L.(P.&T.)t  320 

SifoHCx  linrfi/iis.     I.  (Y.P.) 220 

Sti'opliimimux  rovgli.      I.  (Y.P.)  220 

S.  ohcsns.     Id 220 

iNl'LOUESCENCE. 
0^[ch>lont]larnlgln•ix.  I.(P.iV:T.)  200 

Cones. 
Anohhnn  ahictlx,     L 217 


Gehminating  Seeds. 
UAgriotrx^>Y.     1 214 


LIST   OF    DE.STRUCT1VE   INSECTS. 


875 


2.    SILVER  FIE. 


KooT.s.  Wood. 

I'AOE      '  PAOE 

*frri/ll()fnlj><t  vu/i/(iri.i.     A.  S.  ...  36'J       Ollijlefoetus dcnnesMdex.  I.&L. 
*Mch,h<ntl,a  spp.     L.  (Y.V.)  2  to 
3  summers 200 


Bahk. 

O  C/icrmci  rorrinciis.  A.  (!'.  &;  T.)  304 
*Hijlohiuxahictu.  [.  (Y.P.)t  ...  22.5 
OLcciailim  spp.     A.  (Y.P.  &  V.)  367 

Phsodex  piceae.     I.  P 235 

OStro2}/iu.tc»iiu.'iobesi/x.    I.  (Y.l'.)t  220 

Cambium. 

Ilylaxtrs  pulliafii.t.      I.    k.    L. 

(V.G.)(P.  k'Y.)    262 

Pissodc.1  j)itrae.  L.  (P.  &;  T.)...  235 
TomlcHSchalcograpliHii.    I.  &  L. 

(S.G.)  (P.  &*T.)t  248 

T.  lariris.     I.  &  L.  (H.G.)  (P. 

&T.)t 2.-.1 


T 216 

Sirex  spp.     L.  ( 1 '.  &  T.) 355 

*ToiHicus    liiicKfus:        I.    &;    L. 

(L.G.)T 255 

Buds. 

Tortrtx  rujiiiiitraiui,     L.  T.    ...  340 

YouNU  Shoots. 

O Chcrmes  ^^\^.    A.  (P.  &  T.)    ...303 

Strophosoiiivii  ohesvs.     I.  (Y'.P.)  220 

ToHrix  ruJiiiiitmtM.     L.  T.    ...  340 

Needles. 

*Liparis  momicha.    L.  T.f  310 

O  Melolontha  spp.  I .  ( P.  &  T .)  . . .  200 
OStro2?Jiosoiims  obrsux.     I.  (Y.P.)  220 

*  Tortrtx  rufiinitranu.     L.  T.   ...  340 

Germinating  Seeds. 
O^l^/voto  spp.     L 214 


3.    SCOTS   PINE. 


Hoots. 
ODoloj)iux  marginatux.  L.  (Y.P.)  214 


*(injllotalpa  vulgaris.     A.  S.  ...  36!) 
'Mrlohnitha  spp.  L.  (Y.P.)  2  to 

3  summers 200 

'^Xortiia  ccstigitiliK.     L.  S 322 

'X.  srijetum.     Id 325 


*//.  (Iter.     I.  (Y.P.)     Near  the 

collum 263 

H.  ujwrit.s.     kl 264 

* Miieluph'du.<i piniperdu.     I.&  L. 

(V.G.)     Trees  of  all  ages    ...  265 
*M.   minor.      I.   &   L.      (H.G.) 

Trees  of  all  ages   271 

*Pi.^sodesn(itatus.   L.  (Y.P.&P.)  233 

15ARK.  P.pini.     Id 235 

*n,jlohimahicti.'^.     1.  (Y.P.)   ...  225         *P.  piniphilii.t.     L.  (l\  &  T.)   .      2.35 

*II.  pinaxtri.     Id 232       QTomicun  typogriipkuK.     I.  &   L. 

Lophgrux  piai.     L.  (Y.P.  &  P.)  3.50    ,  (V.G.)  T.f  238 

L.rufux.     Id 3.54  I  O  r.  «««//«««.  I.  &  L.  (F.G.)  &; 

*Pixsodes    notdtit^.      I.  (Y.P.  &         (S.G.)  T.f  246 

P.)  233  OT.rhalcogr,ij>hn*,l.k.h.{i^.G.') 

*P.pini.     Id 235  j     (P.&T.)t  248 

*P.  piniphilus.     I.  (P.  JcT.)    ...235         *r.xtenographv>i.    I.  ic  L.  (V.G.) 

StrophoxomHsroryli.     I.  (Y.P.)  220    i  T 2.50 

S.ohexux.     Id 220    |     *T.  laricix.     I.  &  L.  (V.G.)  (P. 

'  &T.)    251 

Camrium.  '     *T.  hidetitiitiix.      I.  &  L.  (S.G.) 

Ilyhi.'ite.i   palliutux.      I.    iV;     L.  Trees  of  all  ages   253 

(V.G.)  T 262    :       T.ucumimtvs.   I.  A:  L.(S.G.)  T.  2.55 


876 


PROTECTION    AGAINST    INSECTS. 


Wood. 


L.  (1>.  i:  T.) 


tSired-  J  Kin 

2  sumineis 355 

S.  tjigas.     Id 357 

Tomicux   lineatiis.        1.    &;     L. 

(L.G.)  (P.  &  T.)t  -^"'.J 

Buds. 

*  Gastropacha  phii.     Jy.  ( P.  &;  T.)  294 
Lijmris  monarJut.     Id 310 

*roiirixluoliana.  I>.  (Y.  P.&P.)  335 
T.turionana.     Itl 338 

Young  Shoots. 

Ernahi  us  nig rhnis 217 

nulnhiunab'icfiK.   1.    (Y.P.cViP.)  225 

H.p'inustn.     Id 232 

*Myelojf/iilu.i2Ji/iijwrd(i.  I.  Pith 

of  trees  of  all  ages  2C>o 

*M.  minor.     Id 271 

*Tortrlx  huuliana.     L.     Pith  of 

trees  of  all  ages    335 

T.  turUmana.     L.    (Y.P.  &  P.)  338 
O T.  remnella.     L.     2  years.     (Y. 

P.  &  P.)     Resin-galls  339 

Needles. 

*  Gastropacha  pun.  L.  (P.  &  T.)  294 


TAOE 

*  Gcomctra  piniuria.    L.  (P.  et  T.)  32t; 
*Liparix     mniuirha.       L.    (Y.P.) 

(P.  c<c  T.)    ; 310 

*D>plnjrits 2>i>ii-     Jj.  C^-''-  "-^  !'•) 

Social  3.50 

*L.  rufus.     Id 354 

*yoctHa  pinlperda.    l..  (  P.  iV:  'I".)  320 

X.  restigUiIis.     L.    (Y.P.) 322 

Ollliizotrogtismlstitialh,    I.    (P. 

&T.)    210 

SfropJnmiinit.s  roryli.     I.  (Y.  P.)  220 


S.  ohesux.     Id.  .. 
S.  limhatus.     Id. 


220 
220 


Inflorescence. 

O  A  uohium  ahieth.     L 

O.Vrlolont/ia    rulijarin.        I.     (P 
&T.)    ' 

Germinating  Seeds. 
O  Agriotes  spp.     L 


214 

The  above-mentioned  insects  also 
attack  other  species  of  pines,  such  as 
/'.  Strobux,  Lnricio,  Ccinhru.iiiuiitunu  ; 
but  none  suffers  so  much  as  I\  sgl- 

redrin. 


4.   LAECH. 


Roots. 


*Grgllotalpa  vulgar  If.  A.  S.  ...  3r,9 
*jlMoloHf?ta  .«pp.      L.    (Y.P.).    2 

to  3  .summers 200 

yoctua  vestigiaHn.    L.  S 322 

Bark. 
Chermen  laririx.    A.     Trees  of 

all  ages    305 

IlylohluH  ahicfix.    1.  (Y.P.)f  ...  225 

11.  jnneti.     I.  (Y.P.)   232 

Plssodex     notafu.i.        I.     (Y.P. 

&P.)   233 

Cambiu.m. 

I'lssodi'SHotatus.  L.  (Y.  P.  iV;  P.)f  233 
*Tomicus   tgpogrnphu.t.   I.   A:   I^. 

(V.G.),  T.f.' 238 

''T.    amiti/ius.      I.   A:  L.   (F.    or 

S.G.)  T 246 


T.  rJudrogiap/iux.  I.  it  L.  (S.G.) 
(!'■  *:T.)    

T.hiriris.  L.VL.  (V.ti.),P.&T. 
AVooD. 

Sirca"  juvencux.  1j.  T 

Tomirus  Uneatvx.  I.  A;  Jj. 
a.G.)T.t 

Bl-DS. 

Crcidomgia  hcUiwri.    L.    Trees 

of  all  ages 

Needles. 
O  Chcrmex  larlris.    A.  (Y.  1".  cV:  P.) 
" Colcophora  lariccUii.     L.  (V.P. 

&P.)  

Liparix  uionarlia.     1j.  (l*.  iVT.) 
OMrlolontha  spp.     1.  (P.  i:  T.) 
yematux  crlkxoni.      L.      (Y.P.) 
Aoriiia  vcxtlgialix.     L.     (!'.  P.) 

To?-trix  jJiniroJaiM.    L.  T 

( I ERM INATING   Se EDS. 
OAgriofrx>^m> 


3(il 


346 
310 
200 
354 
322 
341 


LIST    OF    DESTRUCTIVE    INSECTS. 


377 


BEECH. 


(injllotitlpa  viihjuris.     A.  S.  ... 
KMdoliinthu  spp.     L.  O'-l'-)    ■■• 

liAKK. 
Ilylohiuxahirfis.     I.  (Y.  l'.)t... 
Vespa  crahro.     1.    (V.l'.  «5«:  1'.) 

CAMHIU-M. 
*Af/rilius  riridi.'<.      L.    (Y.l'.) 

summers . . 

A.  angustuluK.    Id.f- 


2U0 


211 
213 


OScolytm  intrlvatiix.      1.   &   L. 
(H.G.)    P.  ami  biaiichcst... 

"\\'f)f)D. 

Ciisxnx  ucxcidi.      L.    (Y.P.~)      2 

summers 

OJIijlecoetvs  dcrmenfoulex.     L.  T. 

Toiii'icux  dotuest'uiix.  I.  (5c  I.i. 
(1^.0.)  T 

T.  dlspar.  I.  &  T>.  (F.(J.) 
(Y.P.)     

Xextohium  texsclut mil .  I.iS;L.  T. 


2!I3 
21(1 


Buds  akd  Leaves. 

I'ACJE 

O  Apudrnix  cori/ll.    1.  &  L.  ( Y.  1'. ) 

Leaf-rolling    218 

*Bomhyx    pudibunda.      L.   (!'. 

&  T.)  304 

B.  chri/xurrJioea.     It! 308 

OB.  simllis.     L.  (P.  &  T.) 309 

OHihernladefoluiriii.  L.  (P.  &  T.)  331 

*L\puris  vionacha.     L.  (P.  &T.)  310 

Mdolontha^\^\\     I.  (P.  &T.)...  200 
Orrhcxtexfaiji.  I.  &  L.  (Miner). 

Trees  of  all  ages   221 

PliyUuUm  spp.     I.  (Y.P .) 220 

ORhizotrnyus  xolstitUdix.     I.  (!'. 

&T.)    210 

O  nit  ynrh  ites  spp.     L  &:  I..  ( Y. P. ) 

Leaf-rolling    219 

Strophosoiiiu'i  roryVi.     l.(Y.  1'.)  220 

S.  obesux.     Id 220 

Fuurrs. 

Athims  liaeinori-ho'idalis.     L.  ...  214 
Orchedexfayi.  I.  Unripe  fruits  221 


G.   OAK. 


Roots. 
Orynipssi)[>.     1.  6:  L.,  Galls    ...358 

Gryllotalpa  viilgarlit.     A.  S 369 

*Mdulontha  spp.     L.  (Y.  P.),  csp. 
S 200 

Hauk. 

OOvvMspp.     A.  (Y.P.  .V:  1'.)...  3fi(> 

OCyitipx  spp.     I.  k  ij.     Galls  ...  358 

OHyloblus  ahh-tis.     I.  (Y.P.)t...  225 

Vexpa  rnthio.     I.   (Y.P.  i:   P.)  190 

C'AMllIUM. 
Ayrilus  riridis.     L.  (Y.P.)t    2 

su  m mers 211 

*A.  (DiyiLitulun.     Id 213 

Jfyleg'niux    rrenutux.      1,   i:  L. 

(H.fJ.),  T 275 

Si-olyfiix    intrirutitx.      I.    &    L. 
(H.G.).     P.  aud  branches  ...  278 


Wood. 

Coxsm  liyiiiperda.      T>. 

T. 

2 

summers 

291 

0  C.  (exruli.       L.  (Y.P.). 

2 

'^93 

0  Jlylccoetux  dermestoidrx 

L 

T. 

216 

Lymexylon  narale.     L. 

T.  . 

215 

*Tonucus    dixpar.         I. 

k 

L. 

(F.G.),  (Y.P.)  

259 

OXegtuh'nun  tesxchit ii m .   I 

k\. 

.T. 

217 

Buds  axd  Leaves. 

*Bomhyx  nctixtr'ia.     L.  P.   &  T.  302 

B.  chryxorrhoea.     L.  (P.  Ac  T.)  308 

OCyn^q)s^ip.     I.  &  L.     Galls....  358 

*  Geometra  bruiiiata.    L.  (P.  &  T.)  329 

Jlibernia  defoliaria.  L.(P.  &:T.)  331 

O Phyllohiux  spp.     I.  (Y.P.) 220 

Stvophoxoiiivx  spp.     I.  (Y.P.)...  220 
*Toiirix  viridana.     L.  (P.  k  T.)  333 


37H 


I'KOTECTIOX    AGAINST    1NSECT8. 


Li:aves. 

TAOK 

OAj>ofh'ri/s  ronjli.     I.  i:  L.  ( Y.  I'.) 

Leaf-roUiug    :21,s 

OAttrlahux    currlilKniniilrs.        lil.    L'I'.I 
Jiiniihyx  ji)tfli//iifi(I(i.        I..    (P. 

.<cT.)  :504 

LijKinx  tiioniirhii.  L.  (1'.  tV:  D.)  310 
*MfloI,>nt]u,  spi).  1.  (P.  cV:  T.)-.-  200 
OOrr/iexfe.1    qiicrnix.       I.    &    L. 

Suppressed  giowth  223 

(Sec  preceding  section.) 

Young  Shoots. 
Cori/mhifcs  >^l)p.     I.  (Y.P.) 2i:> 


O  ry„;px  spp.     I.  A:  T>.     Galls. 
liijlohiuxahictix.     I.  (Y.l'.M. 
Ltinni  murimiit.     I.  (Y.l*.)  .... 
*l'tich  i/(i/liix      iiiifiratoriiix. 

(V'P.) "...  

Slrophoxomitx  s])p.     1.  (Y.P.)  . 
Telejihontx  ohxcuntx.     J.  (Y.l' 

Acorns. 

Af/rli)fcx  liiictiti/x.     L 

A.  ohxritritx.     Id 

Atlioiix  hdcmorrhoithiVix.     L.  . 

linhiHiiinx  gla mini  III.     \.  ic   L 

Ory//'>spp.     I.&L.     tiall.s.  . 


P.\<iE 

..  3r,8 

22  j 
..  21.-. 
1. 

..  372 
..  220 
.)   isi 


..  211 
.  214 
.  214 
221 
.  3:<8 


7.  HOENBEAM. 

Hoots. 
J/eJoloiitlin  i^pp.     L.  (Y.r.)    ...200 


Leaves. 
inidihundd.       L 


AN'OOI). 
Tniii'iriix     dixjKir.        I.     A:     L. 

(F.G.),  (Y.P.  &  P.) 2.-.<t 

OXedohiuiiitesnelatum.     I.   &;  L. 

T 217 

Buds  and  Leaves, 
*Bi>mhy.r  nciidria.     L.  (P.  &  T.)  302 

]i.  ximiUx.     Id 309 

*Gromctra  hvumaia.      Id 321) 

Uihcrnla  drfoUarid.     Id 331 


JilUllhl/. 

&T.)    

*J[/.  r/iri/xorr/ioea.     Id 

Liparls  vionacha.     Id 

McIoIoHtha    s])!).      I.     'i'lees 

all  ages    

Olthizotroiiuisxolxtltlulix.     Ul   . 

(Sec  preceding  section.) 


FUUITS. 

Aflioiix  /iiiriHurr/iiiidtilix.     L 


304 
30S 
310 

200 
210 


8.   ELM. 


PvOO'l 


anjUolidiM  nihjiirix.     A.  S.  ...  3r,!» 
*M,'lohiHlh<i  spp'.     L.  (Y.P.)     ...200 


Ollijh-xiiiux  nftaliix.     J.  cV:  L.  T. 

Scull/tux.      I.  &  L.  (L.Ci.)  (P.  A: 

T.)    


Wopo. 
Coxxux  Ihjnipn-du.      \..  (P.  i^;  T.) 

2  summersf    2'.t  1 

( '.  (icxritli.     L.  (P.  &  T.) 2!i3 

Buds  and  Leaves. 

J}omh,i.r  ncuxtria.     L.  (P.  &  T.)  302 

Ji.  ch njxorrhoea.     Id 30!) 

Ji.simUis.     Id 301) 

Ilihei-nia  defoliaria.     Id 331 


9.  ASH. 


Hoots. 

J/rUont/ia  !^pp.      L.  (Y.P.)     ...200 


P.AIiK. 
Vrxpa  rrithro.       I.  (^Y.P. 
On  young  slioots  


190 


LIST   OF    DESTRUCTIVE    INSECTS. 


879 


Cambium. 

I-ACJE 

* Jlijlex'inux    frti.riiii.        I.    «S:    Ij. 
CH.U.)     \V.    &i    T.)       15iuk 

rosettes    273 

//.  rrcnatux.     I.  A:  L.  CH.(i.)  T.  27.-) 
Sroli/fun     Geotfniiji.       I.    i^    L. 
(F.G.)  (r.  &  T.)t  277 

Wood. 
CoKsii.1  litjii'ipi'rdd.      \t.     (V.     A: 

T.).     2  suinmer  s 291 

C.     ftexndi.      L.     (Y.?.).       2 

summcr.s      2li3 


Tom  i  CHS     dlxpar.        I.     &     L. 
(F.G.)  (Y.P.  &  r.)    259 

lU-DS. 

Tnii'ti    enrthelln.     L.  (Y.l'.   & 
.     P.)  344 

Leavks. 

Mi'lohmtha   .spp.      I.     Trees  of 

all  ages    200 

TarJnitijliig      vi'u/ rat  a  ri  )/.•<.         \. 
(V>.) ■ 372 


10.   MAPLE 

Hoots. 
■Melohmthu  si.p.     L.  (Y.P.)    ..    : 

Wood. 
Ciixitt/x   Vujn'i perdu.      L.    (P.    i^ 


T.)    

*('.      (icxciili. 


2;»i 


L.      (Y.P.)      2 

summers      292 

Ollijlrroetiis  deriiirxtoidcx.     Jj.  T.  21G 
Tomicun    domexfirits.      I.  &    L. 
(L.G.)T 258 


T.  dJspiir.    I.  &  L.  (F.G.)  (Y.P. 

&P.)   2.59 

OXedohlunitcxsclutum.  I.t*cL.  T.  217 


Leaves. 
Wcloluntha    spp.      I.    Trees   of 

all  ages    200 

Bomhyx  pudihundu.        Ij.    (P. 

&T.)    301 

JL  ehrymrrhoca.     Id 308 

LipariiS  muiiac/ia.     Id 310 


11.   ALDER. 

liooTS.  * Cry[itorrlnjnrhnx   lupathi.       I>. 

*M,hd,intha&}^\\     L.  (Y.P.)    ...200  (Y.P.  4:  P.) 

TomirHxdixpur.    I.  &  L.  (F.G.) 
liAUK.  ^Y  p   &  p  ~) 

Cri/pforrfn/nrhitxliipat/ii.  I.(Y.  i    r> -t-    /» •       ^       j  i  i   !   in 

■'/  •'  -^  ...  ;    OAextnhiumtcxxclatum.    I.t*cL.  1. 

lV.v«/  rrahro.     I.   (Y.P.  i^    P.)   190  I 

CAMiniT-M.  Leaves. 

Af/ril.x    rirldix.      L.  (Y.P.)2  QApoderux  roryli.    \.  k  L.  (Y.V.) 

"""""'^'^     -'^  !  Leaf-rollingf 

Wood.  i        Bomhyx  piidihinidu.      J>.  (V.P. 

O  Comix  Vujnipcrdu.     L.  T.       2  &  P.)    

summers 291  ,       Liparis  mmuicha.     Id 

OC.     acxeidi.        L.      (Y.P.)      2                   R/njnrJiltex si>p.     I.  A:  L.  (Y.P.) 
summei-s     293  Leaf-rollingt 


259 
217 


301 
310 


12.  POPLAR. 
UooTs.                           I                            Bark. 
Mclolo  id /t  u  iii>i>.     L.     (Y.P.)...  200    I        Cryptorrhyiwhux    lapaf/ii.       I. 
I  (V.P.) 


380 


PKOTECTIOX    AGAINST    INSECTS. 


Cambium. 

I'AOB 

Affrilug  vlridls.     L,    (Y.P.)     2 

summers.     (Aspen.) iMl 

0^1.  .sexffufftifun.     L.  T.     2  suni- 
niers 21-1 

Wood. 
Cox.sH.1  Ugnipcrdn.     \i.  V.  k  T. 

2  summers 2'.H 

C.      aoscidi.      L.     (Y.r.)t      2 

summers 2!>;^ 

Cniptori'hy)u-hus  lapuflii.      L. 

(Y.P.) 223 

^Saperda  mrchai-ias.     L.     (Y.P. 

&  P.)     2  summers 280 

S. populiifa.     Id.     Branches...  282 
Sesia  aiii/ormis.     Id 289 


HUD.S. 
O Bomhiix  nrudvui.      L.  (I'.  &  T.) 

LiCAVKS. 

nomhijx  iwiLstriti.     L.  (T.  i<c  T.) 

Oli.  rhrymn-hocd.     Id 

CknjHoiiiela  pojiuli.     I.  tV:  L.  (Y. 

P.)  (stool  shoots)  

C  trem  idac.     Id 

C.      i-ulffdtixxiiiiti.       I.     iV     L. 

(Y.P.)t   

OL'i purls  monarha.  L. (P.  k.  T.)f 
Melulontha  spp.  I.  (P.  cV  T.)... 
Mkizofroffus  sdhfitlnli.f.  Id.  ... 
RhijHchlteg  spp.     I.  &;  L.  (Y.T.) 

Leaf-rolling 


3(t2 
308 


286 
310 
200 
210 

21U 


13.  WILLOW 


KooTs. 
*JJrh>lo/it/iu  spp.     L.  (Y.F.). 


15  a  HK. 
Cnjptdrrlnjnchushiputhi.  I.  (Y. 

P.&P.)  223 

Veitpa  crahro.     I.  (Y.P.) T.tO 

Wood. 
CccUluimjia      xalU'ipcrdd.       L. 

Gall-like  swellings    300 

"Co-smn  lif/niperda.     L.  (P.  k  T.) 

2  .summers 2itl 

C.  aesc-uli.     L.    (Y.P.)    Osiers. 

2  summers 2!»3 

Crijpton-hynchuithijKithi.  L.  (Y. 

P.  &P.)  223 

Saperda  carchariiix.     L.  (Y.P. 

k  P.)     2  summers    280 

li.  popiiliica.     Id 2S2 


P.UUS. 

liombyx  neuxtrla.   L.  (1*.  i:T.)t  302 

07A  rhryxon-hoca.     L.  P.  .V:  T.  ...  3os 

Ji.x'niiilix.     Id 301» 

Yor.NG  SiKxns. 
llallas    chhmina.      L.    (Y.I'.) 
Osiers 332 


Li:avi;s. 

OJJomhy.,- ncnxtriu.     L.f    :^02 

B.  vhryxorrhoca.     L 308 

Chryxomclapopuli.  I.  i:  L.(Y.P.)  284 

C.treiindae.     Id 285 

*C.  rulyatixxima.     U 280 

Halias    cldoriinii.       L.    (Y.P.) 
Terminal    leaves   bound    to-  , 

gethcr 332 

Lipitrix    moiutchii.     L.     Sallow  31<t 

O  Melohmfhd.  spp.     1 20(  • 

t7///  'izotroynx  xnlxtil idlls.      1 210 


14.   BIRCH. 


KooT.s. 
Gryllotdlpa  culfidrix.     A.  S.  ...   3(;:) 
* Melolonthd  s\)[).     L.  (Y.P.)    ...200 


C'A.MltU  :.M. 
Af/rdiix  liridix.     L.    (V.l'.)    2 
summers     211 


1  'exjhi 


Pa  UK.  Wood. 

ihro.     1.  (V.p.   ,*c  P.)  lUU     ,    OCoxxi/xllyniperdd.     L.(I'.&T.) 


LIST   OF    DESTRUCriVK    INSECTS. 


8H1 


( .  iicxculi.  L.  (Y.P.)  2  summers  293 
OIIijlrriM'tus  dcrmrxtoidcs.  L.  T.  216 
Toniint.s     disjiar.        I.     &     L. 

(F.G.)  (Y.P.  &r.)  26<) 

T.dommfiru.s.     I.  &  L.  (L.G.) 

T - 2r,s 

Leaves. 

Jloiilh;/.r    piidihundii.         Ij.     (P. 

k.T.)    :ki4 


B.  Him  His.     L.  (  P.  &  T. ) H(  )<) 

Ilibcntia  drfoliaria.     Id TM 

Liparis  monarha.     Id 810 

Mclolontha  ruh/ariii.     I.     Trees 

of  all  ages 200 

O RIi ynrhites  hetulae.    I .  &  L.  ( X. 

P.)     Leaf-rolling  211) 

07?.  hcfideti.     Id 21!) 

Sf ni/iliiistwuis  i<[)i).     I.   (Y.P.)...  220 


Wood. 
O  Cirnvg  lifj)iij/erda.     L.  (P.  it  T.) 

2  summers  2!ll 

('.    acsnili.     li.   (Y.P.)   2  sum- 
mers       2!iH 

TomicHH   diniicxficiis.      ].    ic    L. 
(L.Ci.)  T.t    2-.S 


15.  LIME. 

^  BUD.S  AXD   LEAVES. 

OBomhjx  .similix:     L.  (P.  &  T.)  279 


Geomcfnt  hruniata.  L.  (P.&T.)  329 
Hihrniia  drfoliaria.     Id H'Jl 


Li  pari. t 


Leaves. 

(^/r//^^      L.  (P.  &  T.)  ;!10 


FItilrridac  sjip.     L, 


IG.   EOBINIA. 

Roots. 
214   I      J/^Wi-/////^  snp.     L 


17.   HAZEL. 


P.AUK    and   SAI'WOOI). 
Agrihis      a/ii/iixfuli/s.       L. 


Buds  and  Leaves, 

HuJaninu^  nucum.     1 

(iromctra  hruniata.     L.    ... 
St rophosomus  spp.  I 


YoDNG  Shoots. 
OHhynrhitex  hetuleti.     I.  A:  L.. 
Stri>j)hiixtimv.'<^\tY).     I 


329 
220 


Leaves. 
r,jli.    L&L, 


OA])odcruH 

rolling 

LipnrixmniKiclia.  \j.  ... 
OIthiinrliitvx?.\)\K     I.iV:L. 

rolling 


Leaf- 


Lcaf- 


FnuiTS. 

Athous  haemurrhoidaU.t,     L — 

JialuninuH  nucum.     I.  ic  L 

n.(jUnidium.     I.  &  L.f  


21S 
310 


214 

221 
221 


In  concluding  this  Chapter,  it  is  desirable  to  impress 
strongly  on  the  forester  the  necessity  for  a  careful  study  of 
forest  insects.  Inattention  to  these  little  creatures  has 
already  in  many  cases  been  severely  punished  by  the  sacrifice 
of  the  labour  of  years.     It  must  not  be  imagined  that  insects 


382 


PROTECTION     AGAINST     INSECTS. 


alwaj's  attack  in  a  secondary  manner,  that  is,  after  a  plant 
has  been  weakened  by  previous  injury  or  disease,  nor  must  the 
danger  arising  from  them  be  under-estimated,  and  this  is 
especially  important  as  regards  coniferous  forests. 

The  most  effective  means  for  combating  inse.ct  attacks 
consist  in  careful  and  cleanly  forest  management,  and  in 
repressing  an  attack  at  its  very  commencement ;  once  it  has 
attained  large  dimensions  man's  efl'orts  against  it  are  almost 
powerless.  In  order  that  his  attempts  at  repression  may  be 
successful,  the  forester  must  know  the  life-history  and  rela- 
tions to  the  forest  of  injurious  insects  ;  for  this  purpose  mere 
book-learning  will  not  suffice,  but  must  be  supplemented  by 
careful  and  continuous  observation  in  the  forest. 


Fio.  194. — Ivhn^jumms  {riwji/ft  iiifi/iiMtitur).      J  in  lli_i,'lit,   ?   on  tree. 
From  "  Ciishcll's  Xiitui-al  History." 


PAET   III. 

PROTECTION   AGAINST   PLANTS. 


385 


PKOTECTION    AGAINST    PLANTS. 

Plants  injurious  to  forests  are  either  weeds  that  cover  the 
soil,  or  dimbers  and  parasitic  phanerogams  or  fungi,  which 
attack  trees  and  forest  plants.  The  'following  sections  will 
contain  an  account  of  these  dangerous  enemies  of  the  forest.* 

•  Hooks  for  reference  on  forest  botany  are  :  Dobner,  Dr.  E.  Ph.,  "  Lehrbuch 
(ler  Hotanik  fiir  Forstniiiuner."  Berlin,  1882.  Schwartz,  Dr.  F.,  "  Forstliche 
Hotanik."  Berlin,  18!»2.  Thaer,  Dr.  A.,  "  Die  landwirthschaftlichen  Unkiauter." 
Berlin,  181)3.  Capital  illustrations  and  directions  how  to  exterminate  weeds. 
The  syetematic  names  of  the  weeds  are  taken  from  Bentham  and  Hooker's 
"  British  Flora,"  5th  edition,  18S7. 


C   C 


386 


CHAPTER    I. 

PROTECTION     AGAINST     FOREST     WEEDS. 
Section  L — General  Account. 

1.  Definition  of  the  term  Forest  Weed. 

The  term  forest  weed  usually  comprises  wild  plants,  which 
by  their  vigorous  growth  in  masses  more  or  less  retard  the 
development  of  young  forest  plants.  By  extending  the 
meaning  of  the  term,  shrubs,  and  even  many  otherwise  useful 
trees,  may  be  included,  which  when  young  injure  the  growth 
of  the  principal  local  forest  species.  When,  for  instance, 
sallows  or  aspens  sprin'g  up  in  large  numbers  in  beechwoods, 
or  birches  among  conifers,  or  even  the  hardy  and  fruitful 
hornbeam  in  the  pole  stage  competes  too  freely  with  beech, 
it  becomes  necessary  to  remove  these  inferior  species  in 
cleanings.  More  detail  on  this  point  is  given  in  sylviculture ; 
it  may,  however,  be  noted  here  that  the  most  numerous  and 
dangerous  forest  weeds  are  woody  plants  of  more  or  less  rapid 
height-growth,  the  most  bushy  ones,  and  those  producing  root- 
suckers  being  the  worst.  In  Burmese  teak  forests,  bamboos 
which  grow  to  heights  of  fifty  feet  and  more  within  a  few 
weeks,  may  render  teak  reproduction  impossible,  until  the 
bamboos  seed  gregariously  and  die,  or  are  killed  by  fires. 

2.   Classification  of  Forest   Weeds. 

In  classifying  forest  weeds,  the  forester  should  be  guided  by 
the  following  points  : — 
•    (a)  Structure  of  the  stem. 

(b)  Duration  of  life  of  the  weed. 

(c)  Local  occurrence. 

{d)  Preference  for  any  particular  soil. 
(e)  Amount  of  mineral  matter  in  its  ash. 
(/)  Demands  as  regards  light  and  sliade. 


FOREST    WEEDS.  387 

{(/)  Kind  of  injury  done. 

(h)  Eelative  amount  of  injury. 

It  is  highly  interesting  to  note  the  changes  which  take  place 
in  the  constituents  of  the  soil-covering  in  a  forest  according 
to  the  species  of  tree  grown,  and  the.  degree  of  density  of  the 
cover. 

a.  Slruciuie  of  Stem. 

Weeds  may  be  either  woodij  or  herbaceous.  To  the  former 
class  belong  broom,  heather,  bilberry,  hawthorn,  blackthorn, 
In-ambles,  elder,  etc. :  to  the  latter,  willow-herbs,  groundsell, 
belladonna,  foxglove,  grasses  (except  bamboos),  sedges,  reeds, 
and  rushes. 

1).  Ihiraiion  of  Life. 

Weeds  may  be  either  annuals,  biennials,  or  perennials. 

IVfost  herbaceous  plants,  except  some  grasses,  are  annuals. 
Mullein  {Verbascum)  and  foxglove  are  biennials,  producing 
foliage  in  the  first  year  and  flowers  alid  fruit  in  the  second 
year.  This  class  is,  however,  rare  among  forest  weeds',  and 
all  woody  plants  and  the  rootstocks  of  many  herbaceous  plants 
are  perennials. 

r.   Loral  Ocnir fence. 

.  Forest  weeds  may  be  classed  as  belonging  to  the  plains,  to 
swamps,  hills,  or  mountains.  Of  these,  the  flora  of  swamps 
and  of  high  mountains  are  most  specialised. 

(I.  Xdiuic  of  Soil. 

Weeds  may  be  partial,  or  restricted  to  certain  soils,  or 
indifferent  as  to  soils. 

The  restricted  class  is  divided  into  plants  special  to  sand, 
clay,  loam,  calcareous  soil,  or  to  peaty  and  sour  soils.  It 
should,  however,  be  remembered  that  the  plants  produced  in 
any  locality  are  affected  by  the  subsoil  and  surrounding 
conditions  as  well  as  by  the  surface-soil,  so  that  we  must 
not  be  surprised  if  a  sandy  soil,  for  instance,  occasionally 
produces  plants  peculiar  to  other  soils. 

Most  forest  weeds  are  indifferent  as  to  soil,  and  appear  on 
soils  differing  from  one  another  both  physically  and  chemically. 

c  c  2 


388  PROTECTION   AGAINST    PLANTS. 

On  sandfj  soils  we  find  chicflj'  ling  {Callium  rulfiaris,  Sal.) 
and  heather  {Erica),  broom  {Cytisus  scoparius,  Link.),  lyme- 
grass  {Elymus  arenarius,  L.),  niaram-grass  {Psamma  araiaria, 
Beauv.),  sand-sedge  {Carex  arenaria,  L.) ;  Festuca  r/lauca, 
Schrad. ;  Panicum  f/lahrum,  Gaud. ;  etc. 

On  clai/  soils:  coltsfoot  {ThssUckjo  Farfara,  L.),  wound- 
wort {StacJn/s  pahistris,  L.),  marestail  {Equisetum),  cotton- 
grass  {Eriophorum),  rushes  {Junciis). 

On  loam,  on  account  of  its  favourable  nature,  very  numerous 
weeds  abound,  such  as  all  good  meadow-grasses,  bindweed 
{Convolvulus),  Veronica,  etc. 

Calcicolous  weeds  are  VilHirnuni  Lantana,  L.  (way  faringtree  ; 
rock-rose  {Helianthrmum  vuhjarc,  Gaertn.) ;  Stachys germanica, 
L. ;  liuhus  saxatilis,  L. ;  many  PapHionacece,  and  of  grasses, 
Melica  and  Sesleria. 

On  rich  liunius  soil:  rasjiberr}^  {Ruhus  Iclaeus,  L.),  balsam 
{Impatiens  Noli-me-tanriere,  L,),  hemp-nettle  {Galeopsis  Te- 
trahit,  L.),  black  night-shade  {Solanum  nigrum,  L.),  etc. 

On  peats :  we  find  mint  {Mentha  'pulustris,  L.,  etc.) ;  bog 
myrtle  {Myrica  Gale,  L.)  ;  Vaccinium  uUginos'um,  L. ;  Carex, 
Eriophorum,  Juncus,  Scirpus,  lousewort  {Pedicularis),  dock 
{Iluniex),  loosestrife  {Lythruni  Saliearia,  L.),  peat-moss 
{Sphagnum,  sp.),  etc. 

On  saline  soils:  sea  milk- wort  {Glaux niaritima,lj.,  Plantago 
maritima,  L.),  samphire  {Critlunum  maritimum,  L.),  marsh- 
samphire  {Salicornia  herhacea,  L.),  salt- wort  {Salsola  Kali, 
L.),  Armeria  vulgaris,  Willd. ;  sea-lavender  {Statice),  sea-holly 
{Eryngium  maritimum,  L.),  maram-grass,  etc. 

e.  Mineral  Substances  in  Ashes  of  Weeds. 

The  mineral  character  of  the  soil  on  which  plants  will  thrive 
cannot  be  decided  by  the  quantity  of  any  substance  such  as 
silica,  calcium  carbonate,  or  sodium  chloride,  which  may  be 
found  in  their  ashes.  Different  parts  of  the  same  plant 
also  contain  different  proportions  of  chemical  substances. 
Thus,  there  is  mucli  silica  in  the  stem  of  grasses,  and  more 
phosphates  and  potash  in  their  seeds. 

The  physical  nature  of  the  soil,  i.e.,  its  degree  of  moisture. 


FOREST    WEEDS.  389 

capacity  for  being  heated,  porosity,  etc.,  has  more  influence 
on  the  growth  of  plants  than  its  chemical  composition,  though 
the  latter  has  an  indirect  influence  on  the  physical  nature  of 
soils. 

In  the  strife  l)etween  weeds  and  cultivated  plants,  the  former 
gain  ground  by  the  easy  dissemination  of  their  seed  by  wind, 
water,  or  birds,  as  well  as  by  their  superiority  in  the  struggle 
for  light  and  for  space  for  their  roots.  If  cultivation  of  the 
fields  were  to  cease  in  Europe,  it  is  certain  that,  in  100  years, 
only  grassland,  forest,  or  swamp  would  be  found,  according 
to  the  degree  of  humidity  of  the  soil. 

/.  Demands  as  to  Liijht. 

Plants  are  termed  lightdemanding  or  shadebearing  accord- 
ing to  their  relative  demands  for  light,  or  capacity  for  bearing 
shade. 

Heather  is  a  decidedly  liglitdemanding  plant,  bilberry 
{Vaccinium  Myrtillus,  L.),  a  half  shadebearer :  the  holly, 
juniper,  and  Daphne  are  shadebearing  plants,  as  they  flourish 
in  dense  woods.  Ivy  {Ilcdera  Ileli.v,  L.)  and  butcher's  broom 
{Ruscns  acnleatus,  L.)  are  also  even  more  shadebearing. 

(J.  Kind  of  Injury  done. 

Weeds  may  overtop  young  trees  and  deprive  them  of  light 
and  dew ;  they  may  constrict  them,  as  in  the  case  of  the 
woodbine,  or,  like  the  bindweed,  completely  stifle  them  by 
growing  over  them ;  they  may  smother  and  bend  them  down 
when  pressed  on  them  by  snow,  as  dead  bracken ;  or,  like  the 
peat-moss,  Sphaynum,  cause  swamps.  Some  weeds,  such  as 
bilberry,  may  form  a  dense  mat  with  their  roots,  so  that 
natural  regeneration  of  trees  may  be  obstructed. 

//.  Degree  of  Injury  done. 

Weeds  may  be  classed  as  very  injurious,  injurious,  or 
only  sUyhtbj  injurious.  Many  forest  weeds  are  either 
technically  or  indirectly  useful,  as  will  be  explained  in  the 
next  paragraph. 


390  PROTECTION    AflAIN.ST    PLANTS. 

3.    Utiliti/  <>/  Certain    ]Vi\'(ls. 

Some  weeds  are  divccUy  or  indirectlij  useful  in  woods. 

Many  weeds,  such  as  grasses,  are  directly  useful  for  fodder, 
thatch,  or  litter,  or  may  be  used  by  manufacturers,  or  for 
medicine.  A  full  account  of  such  plants  is  given  under 
Forest  Utilisation.  The  fruits  of  many  shrubs  alTord  useful 
food  for  men,  mammals,  and  birds. 

Weeds  may  also  be  indirectly  useful  in  the  following 
ways : — 

(a)  Soil-indicators.  Giving  evidence  of  certain  physical  or 
chemical  qualities  of  soils. 

(b)  Soil-fixers.  Binding  the  soil  on  steep  slopes,  or  on 
shifting  sands  (sand-fixing  grasses). 

(c)  Soil-improvers.  Enriching  the  soil  with  their  detritus, 
and  maintaining  its  moisture,  reducing  radiation,  and 
especially  by  preventing  extremes  of  temperature  in  the 
surface  soil  (mosses),  other  than  Polytrichum  and  SpJiafiniiw. 

(d)  Nurses,  for  young  tender  species  in  localities  exposed  to 
frost,  dry  winds,  or  insolation.  Thorny  bushes  and  weeds  of 
an  erect  habit,  such  as  the  broom,  are  most  useful  in  this 
respect.  Thorny  bushes  also  protect  all  kinds  of  forest 
plants  against  grazing  animals  or  deer,  and  afford  shelter 
to  useful  birds. 

On  these  grounds  forest  weeds  should  not'  always  be 
extirpated,  but  only  when  they  do  more  harm  than  good. 

4.  Dainar/e  done  hi/  Forest   ]Veeds. 
A.    General  Nature  of  Damage. 

The  damage  done  by  forest  weeds  is  either  direct  or  indirect, 
many  weeds  being  hurtful  in  both  ways. 

Directly  injurious  are  poisonous  plants,  such  as  Daphne 
Mezereum,  L.,  nightshade,  or  belladonna,  which  are  hurtful  to 
animals  grazing  in  the  forests.  A  dense  growth  of  black- 
thorn, roses,  brambles,  etc.,  is  also  a  great  hindrance  to 
fellings,  and  may  therefore  be  considered  directly  hurtful. 

The  indirect  hurtjulness  of  weeds  is  due  to  the  following 
causes  : — 


FOREST    WEEDS.  391 

i.  The  matted  roots  of  many  weeds  increase  the  difficulty 
of  reproduction  of  the  forest,  as  in  the  case  of  heather,  bilberr}', 
and  couch-grass. 

ii.  The  removal  of  valuable  mineral  matter  from  the  soil, 
which  thus  becomes  impoverished,  for  instance,  of  potassium 
phosphate  in  grass-seeds. 

iii.  Mechanical  injury  to  young  forest  plants  by  birch, 
aspen,  sallow,  grasses,  etc.,  owing  to  deprivation  of  light,  heat, 
air,  dew,  or  rain.  Lightdemanding  plants  are  thus  soon 
killed,  and  even  shadebearing  species  cannot  long  withstand 
such  injuries. 

iv.  Injuries  by  smothering  or  constricting  plants,  as,  in 
summer,  by  honey-suckle,  clematis,  convolvulus,  wild  hops, 
etc.  In  winter,  by  being  pressed  down  on  the  plants  by 
snow;  bracken,  tall  grasses,  etc. 

v.  Eetention  of  excessive  moisture  in  the  surface- soil  during 
wet  weather,  and  formation  of  swamps ;  consequent  increase 
of  damage  by  frosts  :  all  peat-plants,  and  especially  Sphagnum, 
increase  the  swampiness  of  the  soil. 

vi.  A  dense  growth  of  grass  or  weeds  may  prevent  dew  or 
light  rains,  which  merely  dry  off  the  surface  of  the  weeds,  from 
penetrating  the  soil,  and  is  thus  very  hurtful  to  plantations 
and  sowings  during  droughts.  This  may  be  easily  proved  by 
digging  up  a  sod  and  examining  the  soil  beneath  it.  Besides 
excluding  moisture  from  the  soil,  the  grasses,  etc.,  draw  up 
the  soil-moisture  from  below  and  transpire  it  into  the  air, 
so  that  the  denser  the  growth  of  grass,  the  drier  the  soil 
becomes. 

vii.  Certain  plants  produce  a  sour  or  dry  humus  which  is 
unsuitable  for  most  forest  trees :  this  is  the  case  with  heather, 
reeds,  and  other  sour  grasses,  sedges,  etc. 

viii.  Shelter  is  afforded  by  grass  and  herbage  to  mice  and 
insects. 

ix.  Weeds  and  especially  heather,  increase  danger  from 
forest  fires. 

X.  Parasitic  plants,  other  than  fungi,  that  remove  sap 
from  forest  plants.     They  may  be  classified  as  follows : — 

a.  Parasites  germinating  and  growing  in  the  living  tissues 
of  their  hosts  (mistletoe  and  Lomnfhus). 


392  PROTF,CriON    ArjATNST    PLANTS. 

/?.  Parasites,  such  as  dodder  (X'lisruta),  germinating  on  the 

ground,  l)ut  eventually  attaching  themselves  to  forest 

plants. 

y.  Parasites  nourished  partly  hy  their  own  roots,  and  partly 

by  attaching  themselves  to  useful  plants.     Broomrape 

{Orohanche)  on  broom,  furze,  ivy,  hemp,  lucerne,  etc. 

Lathraca  squamaria,  L.,  on  the  roots  of  trees,  especially 

hazel. 

xi.  Epiplii/trs.      Lichens   do   not  remove   sap  from    forest 

plants,   but  live  on  water,  air,  and  rotting  baric,  but  when 

attached  to  trees  they  are  injurious  by  blocking  the  lenticels 

and  preventing  necessary  aeration   of   the   internal   tissues. 

They  harbour  numerous  insects,  and  increase  the  weight  of 

snow  on  the  crowns  of  trees  during  winter.     Trees  with  rough 

bark,  such  as  spruce,  larch  and  pines,  are  most  subject  to 

attacks  of  lichens,  which  increase  in  number  with  the  age  of 

their  hosts.     The  l)ranches  are  more  subject  than  the  boles  to 

these  attacks, 

Incrustating  lichens,  such  as  Imhricaria,  Ilatt/sma,  and 
Lecanora  are  worse  than  beard-like  lichens,  Usitia,  Ercniia, 
and  Alectoria.  Lichens  do  most  damage  in  moist  valleys  and 
in  crowded  woods, 

xii.  Some  weeds  serve  as  hosts  to  injurious  fungi,  which 
may  afterwards  spread  to  forest  trees  or  to  agricultural  crops. 
Many  i^arasitic  fungi  are  most  frequently  found  on  weeds, 
or  attack  agricultural  crops  only  after  passing  one  stage 
of  their  existence  on  a  weed. 

Thus,  certain  grasses — e.g.,  Arrhenathcntm  and  Arena — 
spread  certain  kinds  of  rusts  on  to  cereal  crops,  such  as 
Tilletia  caries,  Tub,  and  Ustila[/o  carho,  Tub  Puccinia  f/ra- 
ininis,  Pers.,  on  wheat  comes  from  Accidiiim  Bcrheridis  on  the 
barberry  ;  and  oat-rust  {P.  coronata,  Corda)  from  Ijuckthorn, 
Foresters  should  always  look  with  suspicion  on  any  fungus 
appearing  on  wild  plants. 

B.    Special  Forms  of  Damage  done  by  "Weeds. 

The  amount  of  damage  done  to  forests  by  particular  weeds 
depends  on  their  wide  dissemination  and  on  the  vigour  and 
special  nature  of  their  growth.     These  are  determined  chiefly 


FOREST    WEEDS.  393 

by  the  locality,  the  prevailing  system  of  forest  management, 
and  the  state  of  the  weather  during  the  growing  season.  In 
the  second  place,  by  the  species  of  tree  and  age  of  crop. 

Weeds  are  disseminated  chiefly  by  winds  which  carry  light 
seeds  and  fruits  by  millions,  as,  for  instance,  the  fruits  of 
ComjwsiUe  ;  many  birds,  especially  thrushes  and  blackbirds, 
disseminate  seeds  either  by  pecking  at  the  ripe  fruit-heads  and 
causing  the  wind  to  disperse  the  seeds,  or  by  eating  the  fruits 
and  voiding  the  indigestible  seeds.  This  is  especially  the  case 
with  hawthorn.  Other  birds,  such  as  finches,  eat  the  seeds  of 
many  weeds  and  are  so  far  serviceable.  Hares,  deer,  and  other 
animals  also  carry  seeds  about  in  their  fur.  The  seeds  of  many 
riparian  plants  are  carried  down  by  streams  and  inundations, 
i.  Damage  according  to  Species  of  Tiiek. 

Slowly  growing  species  are  more  easily  injured  by  the 
growth  of  weeds  than  fast-growing  ones,  and  of  these,  light- 
demanding  species  suffer  most.  The  vigour  of  the  weeds  is 
greatest  on  the  most  fertile  soils. 

The  following  scale  shows  the  degree  in  which  the  different 
trees  suffer  from  a  strong  growth  of  herbage. 

Suffer  most: — Osier- willows,  elm,  ash,  maples,  sweet  chest- 
nut, silver-fir,  and  spruce. 

Suffer  less: — Beech,  hornbeam,  and  lime. 

Suffer  still  less : — Oaks,  alder,  tree-willows,  Scots  and  Black 
pines,  and  larch. 

Suffer  least: — Birch,  aspen,  poplars,  sallows,  robinia,  species 
of  Sorbus,  Pyrus,  Pruuus,  and  Weymouth  pine. 

This  scale,  of  course,  will  vary  for  different  localities  which 
suit  certain  trees  better  than  others. 

ii.  Systems  of  Management. 

In  high  forests  with  natural  regeneration,  or  artificially 
planted  under  cover,  the  soil  is  not  so  liable  to  become  covered 
with  weeds  as  in  the  clear-cutting  system,  which  favours  the 
spread  of  weeds  in  the  highest  degree.  The  shelterwood 
comimrtment  system,  also,  if  not  very  carefully  managed, 
sometimes  gives  rise  to  masses  of  weeds  on  the  felling-areas. 

On  fresh,  and  'especially  damp,  rich  soils,  after  a  clear- 
cutting,  a  dense  growth  of  grass  and  weeds  springs  up  in  a 


394  PROTECTION    AGAINST    PLANTS. 

surprisiiifjly  short  time.  Tlius,  foxgloves  and  groundsel  on 
sandsto;ie  rock  ;  balsams  and  willow-herbs  on  basalt ;  brooms 
and  genista  on  sandy  soils — spring  up  in  masses  after  a 
felling.  This  can  be  explained  only  by  a  supposition  that 
the  seeds  of  these  weeds  remain  dormant  in  the  soil,  and 
germinate  only  when  the  removal  of  the  trees  allows  enough 
heat  and  air  to  reach  them.*  Jhuming,  or  the  thorough 
burning  of  branch  wood  on  the  soil,  after  a  clear-felling,  may 
destroy  seeds  of  weeds  in  the  upper  layers  of  the  soil,  and 
thus  keep  it  free  from  w^eeds  until  it  has  been  restocked  with 
forest  growth. 

iii.  Age  of  Wood. 

Forest  trees  are  most  endangered  by  weeds  in  the  first  few 
years  of  their  life.  Forest  nurseries  and  cultivations,  there- 
fore, suffer  most  of  all,  and  of  these,  sowings  and  natural 
regeneration-areas  more  than  plantings.  Where  weeds 
abound,  very  small  transplants  should  not  be  used,  and 
frequently  four  or  five-year-old  plants  are  preferable. 

Some  poles  and  coppice-shoots,  and  especially  osier-willows, 
are  attacked  and  frequently  killed  by  climbers  and  parasites. 

In  tropical  countries,  trees  of  all  ages  are  liable  to  be  killed 
by  the  strong  woody  climbers  and  twiners  (lianes)  which 
abound  in  the  forests  of  these  regions  and  attain  several 
feet  in  girth.  These  lianes  may  mount  to  the  top  of  the 
highest  trees,  depriving  their  crowns  of  light  and  bending 
down  and  breaking  poles  with  their  w^eight.  The  twiners  also 
constrict  trees,  moulding  their  stems  into  corkscrew  shapes, 
and  in  the  case  of  trees  wath  a  sapwood,  the  passage  of  sap 
may  be  so  interfered  with,  that  the  trees  are  killed. 

iv.  Locality. 
Fertile,  fresh,  and  moist  soils,  especially  on  basalt,  produce 
more  weeds  than  soils  over  dry  sandstone  rock.  Damp  air 
also  favours  the  growth  of  weeds,  as  can  be  seen  from  the 
vigorous  weedy  growth  on  mountains.  Fortunately,  on  good 
soils,  the  growth  of  forest  trees  also  enables  them  to  get  out  of 
the  reach  of  the  weeds  sooner  than  in  unfavourable  localities. 

*  "  Cultiiiversuclie  mit  luhenden  samen."  C'eiitiallblatt  f.d.  gcs.  Foislwcsen, 
1S'.)4,  p.  138. 


FOREST    WEEDS.  395 

V.  Density  of  Forest  Guowtii. 
The  growth  of  weeds  which  have  taken  possession  of  the 
soil  after  a  feUing,  makes  way  for  a  covering  of  moss,  needles 
or  dead  leaves,  after  the  forest  has  been  reconstituted.  When 
age  again  begins  to  open  out  the  wood,  or  when,  owing  to  bad 
management,  or  to  accidents,  thin  places  and  blanks  appear, 
weeds  reappear  in  direct  proportioif  to  the  amount  of  light 
admitted  to  the  soil. 

vi.    WkATHKI!. 

Damp  warm  years  are  most  favourable  to  a  growth  of  weeds, 
and  during  such  years  tender  forest  species  require  little  or 
no  shelter.  Hence  for  both  these  reasons  weeds  are  then 
most  hurtful. 

vii.  Habit  of  the  Weeds. 

Perennial  weeds,  and  especially  those  which  produce  root- 
suckers,  are  much  worse  than  annuals.  Also  those  with  dense 
foliage  and  those  which  are  social  over  extensive  areas,  or 
gregarious  in  patches,  injure  forest  plants  more  than  scantily 
foliaged  and  solitary  growing  weeds.  Species  such  as  black- 
thorn, aspen,  and  forest-willows  soon  get  the  ujiper  hand  of 
other  weeds. 

Weeds  which  by  their  decomposition  yield  dry  or  acid  humus 
are  also  hurtful,  as  they  produce  soil  unsuitable  for  forest 
vegetation.  Dry  humus  formed  of  lichens,  etc.,  contains  little 
carbon  dioxide,  easily  crumbles,  decomposes  with  difficulty, 
and  absorbs  very  little  water.  Acid  humus,  on  the  other 
hand,  formed  by  sedges  and  peat-plants,  injures  by  exhaling 
marsh-gas,  and  by  containing  certain  organic  acids  that  are 
detrimental  to  tree-life. 

5.  Protection  against  Weeds. 
(I.  Preventive  3Ieasiirrs. 

The  following  rules  for  keeping  down  forest  weeds  should 
be  observed : — 

i.  Maintenance  of  the  Density  of  the  Fouest. 

Great  care  must  be  taken  in  the  shelterwood  systems,  on 
soil  liable  to  become  weedy,  that  the  fellings  are  not  too  open. 
The  seeding-fellings  must  be  dark,  and  the  secondary  fellings 


396  IMtOTKcnON    ArJAIX.ST    PLANTS. 

made  gradualh'.     All  blanks  hIiouUI  be  speedily  filled  in  with 
strong  transplants. 

ii.    MODKUATKLY    LoNH    KoTATIONS. 

Long  rotations  should  be  avoided,  and  woods  of  light- 
demanding  species  (oak,  Scots  pine,  or  larch),  should  be 
underplanted  at  the  riglit  time  with  shadebearers  (beech, 
silver-fir,  spruce,  Weymouth  pine,  etc.). 

If  a  soil-protection  wood  is  to  serve  its  proper  purpose,  it 
must  be  introduced  before  grasses  have  sprung  up  and  lielped 
to  dry  the  soil. 

iii.   Rapid  Ri:i'lantinc;  of  Ci.EAUEn  Areas. 
Clear-cuttings   should    be    rapidly    restocked    with .  strong 
transplants  planted  closely. 

iv.  Maintenance  of  Sou.-Coveiunu. 
The  natural  soil-covering  of  dead  leaves,  needles  or  moss 
should  be  maintained,  by  keeping  up  a  dense  cover,  and  by 
preventing  the  removal  of  litter. 

V.    DltAINAGE. 

Drainage  should  be  carried  out  on  very  damp  localities, 
before  they  are  re-stocked. 

Vi.    GllAZINO. 

A  dense  growth  of  heather  may  be  kept  down  by  sheep. 
Cattle  are  useful  in  young  deodar  woods,  with  a  dense  growth 
of  shrubs,  which  grow  most  luxuriantly  in  the  Himalayas. 

vii.  Rules  fou  Fokest  XrifsiciaEs. 

Nurseries  should  not  be  too  near  fields.  The  seed-beds  and 
nursery  lines  should  be  carefully  weeded  or  hoed  before  the 
weeds  blossom,  and  during  rainy  weather.  Burned  sods 
should  be  used  as  manure,  as  this  destroys  the  seeds  of  weeds, 
^lanure  from  old  manure  heaps  is  often  full  of  nettle-seed, 
and  when  burnt  compost  is  not  strong  enough  for  a  nursery, 
artificial  manures,  such  as  basic  slag,  in  autumn,  and  sodium 
nitrite  or  kainit,  in  the  spring,  should  be  sprinkled  between 
the  lines  of  plants.  If  farmyard  manure  is  used,  it  is  better  to 
grow  a  crop  of  jiotatoes  before  restocking  with  forest  plants. 


FOREST    WEEDS.  397 

Spaces  between  plants  may  be  covered  with  moss,  dead 
leaves  or  sawdust.  Tliis  prevents  the  soil  from  caking  and 
retains  moisture  near  the  surface,  and  thus  replaces  completely 
the  expensive  processes  of  working  the  soil,  weeding  and 
watering.  In  damp  places,  burned  compost  introduces  liver- 
wort {Marchantin  polijniorplta,  L.),  l)ut  tin's  does  no  liarm  to 
the  plants. 

b.  Remedial  Measures. 

The  nature  of  remedial  measures  to  be  adopted  depends  on 
the  habit  of  the  weeds,  their  degree  of  development,  and  the 
nature  of  the  locality.  The  simplest  measures  will  often 
suffice,  but  sometimes  special  measures  must  be  taken  as 
follows:  — 

i.  In  order  to  remove  too  great  a  soil-covering  of  grass  and 
herbage,  cattle  may  be  admitted,  or  the  weeds  may  be  pulled 
up  or  cut  down,  always  before  the  blossoming  period.  In 
very  bad  cases  the  hoe  or  plough  may  be  used  all  over  the 
area,  and  the  land  made  to  produce  a  field-crop  before  being 
restocked  with  forest  growth.  The  cutting  of  grass  and 
herbage  may  be  profitable,  or  the  cost  of  the  operation  at  least 
covered  by  the  sale  of  the  produce.  The  weeds  when  mixed 
with  lime  may  be  collected  into  heaps,  and  then  yield  valuable 
manure  for  forest  nurseries,  or  they  may  be  burned  and  their 
ashes  spread  over  the  soil. 

ii.  If  the  soil  is  covered  with  short  woody  plants  tliey  ma}' 
be  mowed  down  or  pulled  up,  as  in  tlie  case  of  heather  ;  rasp- 
berries may  be  simply  beaten  down,  and  softwoods,  such  as 
sallows,  pulled  up,  or  cut  off  at  about  one  foot  from  tlie  ground, 
or  the  woody  plants  may  be  girdled  close  to  the  ground. 

This  cutting  should  be  done  in  July,  at  the  height  of  the 
growing  season,  when  the  power  of  reproduction  is  least, 
as  there  is  then  least  reserve-material  in  the  roots  and 
rhizomes.  In  coppice  and  coppice-with-standards,  inferior 
species  such  as  blackthorn  should  be  cut  out  several  years 
before  the  underwood  is  felled.  Binding  tightly  suckers  or 
shoots  of  woody  weeds  with  wire  is  sufficient  to  kill  them. 

iii.  To  remove  from  trees  the  coating  of  lichens  and  moss 
which  close  their  lenticels  and  deprive  them  of  air,  various 


398 


PROTECTION    A(;AIXST    I'LANTS 


instruments  may  be  used,  as  shown  in  the  figures ;  but  this 
would  only  be  done  for  specially  valuable  trees  or  in  orchards. 
A  mixture  twenty  parts  by  weight  of  wood-ashes  with  one 
part  carbolic  acid  may  also  be  used.  This  is  boiled  and 
smeared  on  the  stems  with  a  brush,  and  in  a  few  days'  time 
all  the  lichens  will  fall  off.  Limewater  has  the  same  effect. 
A  nn'xture  of  3  lbs.  of  blue  stone,  2  lbs.  of  lime,  and  30  gallons 
of  water  may  also  be  used.  It  is  best  to  remove  lichens  on 
dry  days  in  spring,  or  autumn,  as,  thus,  numerous  injurious 
insects  are  also  killed. 

iv.  In  Indian  forests,  woody  climbers  are  cut  periodically, 


Steel- wire  brush. 


Ditto,  with  hole  for  handle. 


and  especially  two  years  before  fellings,  as  they  then  rot  and 
no  longer  bind  trees  to  be  felled  to  others  intended  to  remain 
standing. 

Section  II. — Special  Account. 

The  following  is  a  list  of  the  weeds  most  hurtful  in  the  forests 
of  Central  Europe,  with  an  account  of  the  special  means  of 
combating  them.  It  is  best  to  consider  them  in  order  of  their 
demands  on  light  and  the  amount  of  injury  they  do,  and  not 
according  to  their  systematic  botanical  arrangement. 

The  following  groups  occur  : — 

1.  Li'ihtdemanders,  which  generally  spring  up  on  blanks 
and  felling-areas. 

2.  llulf-shadehraiers,  occurring  in  the  interior  of  woods  as 
soon  as  they  become  too  light.  All  shrubs  and  herbs  belong- 
ing to  this  class  grow  all  the  better  in  the  open. 


BROOM.  899 

3.  Shadehearers,  springing  up  in  more  or  less  closed  woods. 

4.  Weeds  of  net  or  tuvfy  soils. 

5.  Lianes. 

6.  Parasitic  2)hancrogams. 

7.  Weeds  acting  as  liosts  to  iiijiirions  fuufii. 

In  each  group,  first  the  woody  species  and  then  herbaceous 
ones  will  be  considered. 

1.  lAglitdemandinf)  iceeds. 
These  weeds  injure  forest  plants  by  overtopping  them  and 
excluding  light  and  other  atmospheric  influences,  or  by 
occupying  the  soil  with  their  roots,  or  in  both  ways.  They 
may  also  produce  a  humus  which  is  unfavourable  to  forest 
growth. 

a.  Broom  {Cijlisus  sroparhts,  Link.). 

This  evergreen  shrub  attains  six  feet  and  more  in  height, 
and  prefers  deep  sandy  or  loamy  soil ;  it  springs  up  on  clear- 
ings in  mild  localities,  and  is  found  throughout  Europe.  The 
seed  may  remain  dormant  in  the  soil  for  many  years.  It  may 
be  submerged  in  water  for  several  decades  without  losing  its 
germinative  power.  Burning  undergrowth  often  results  in 
the  germination  of  dormant  broom  seed,  and  in  the  Ardennes, 
where  basic  slag  is  put  on  to  heather  soil,  a  dense  crop  of 
broom  often  results. 

Jiroom,  wlien  not  growing  too  densely,  may  be  useful  to 
young  broadleaved  plants,  such  as  oak-saplings  and  stool- 
shoots,  by  aftbrding  them  shelter  against  frost,  but  a  dense 
growth  of  broom  is  very  destructive  to  one-  and  two-year-old 
pine  and  larch  sowings. 

Protective  Measures. 

It  is  best  to  uproot  tbe  young  broom  at  its  first  appearance, 
or  it  may  be  cut  oflf  at  mid-stem,  when  the  stems  dry  up  and 
do  not  shoot  out  again.  This  plant,  as  well  as  all  other  weeds, 
should  be  removed  before  the  seeds  are  ripe,  in  this  case  in 
July.  Its  removal  may  repay  the  cost,.a8  it  is  used  for  litter, 
fuel,  and  for  making  brooms,  hedges  or  thatch.  It  may  be 
browsed  down  by  sheep.     In  Italy,  between  the  All)an  and 


400  PHOTKCTIOX    AGAINST    I'LAXTS. 

Sabine  mountains,  regular  crops  of  broom  are  cultivated  wiLli 
rotations  of  five  or  six  years,  and  used  for  fuel. 

h.  Furze  {Ulcr). 

There  are  two  species  of  furze  common  in  Britain,  Ulcx 
sitropaeus,  L.,  and  U.  nana,  Forst.  The  latter  blossoms  in 
the  autumn,  when  the  larger  species  is  in  fruit,  the  former  in 
the  spring  and  early  summer. 

In  order  to  clear  furze  from  tracts  that  are  to  be  planted,  it 
is  best  to  burn  it  in  the  summer,  and  then  cut  down  the 
burned  stems.  It  grows  slowly  from  the  rootstocks,  and  a 
new  plantation  will  come  away  from  it. 

There  are  several  species  of  Genista,  termed  in  England 
dyer's-weed,  needle-furze,  etc.,  which  may  be  treated  like 
broom,  but  are  never  so  troublesome  here  as  on  the  Continent. 

c.   Wild  Briar  (Rosa). 

There  are  several  species  of  wild  briar,  the  commonest  being 

Rosa  canina,  L.     They  spring  up  wherever  the  soil  is  not  too 

wet,  both  in  plains  and  hills.     Their  great  power  of  sending 

out  suckers  renders  them  very  injurious  to  forest  growth,  and 

the  best  way  to  get  rid  of  them  is  to  dig  them  up  by  the 

roots. 

d.  Common  Ling  and  llealher. 

Ling  {Callnna  ruhjaris,  Salisl).),  Scotch  heather  {Erica 
(■i)u'rca,  L.),and  cross-leaved  heather  {E.  Tetralix,!!.),^^  well 
iis  other  species  of  Erica,  cov.er  large  areas,  the  first  chietiy  in 
Central  and  Northern  Europe,  the  second  in  Western  Europe, 
from  tlie  south  of  Spain  to  Norway,  and  the  last  to  the  west 
in  Southern  Europe,  but  in  the  north  extending  eastwards  as 
far  as  Sweden  and  Livonia.  They  grow  in  very  variable  soils, 
but  prefer  sandy  tracts,  especially  when  poor  and  dry.  A 
luxuriant  growth  of  heather  is  a  sure  sign  of  a  poor,  shallow, 
sandy  soil,  or  of  one  that  may  have  become  impoverished  by 
bad  management.  Heather  is  injurious  not  only  by  filling 
the  ground  with  its  roots,  and  excluding  atmospheric  influ- 
ences, but  also  by  producing  as  it  decays  an  unfavourable 
humus,  on  which  only  pines,  birch  and  aspen  thrive.  It  is 
highly  inflammable  in  the  spring,  and  when  burning  in  dry 
windy  weather  may  cause  extensive  conflagrations  in  coniferous 


COMMON    LING    AND    HEATHER. 


401 


forests.  Heather  is  soon  killed  by  the  shade  of  trees.  In 
Scotland,  lichens  fostered  by  the  moister  air  produced  by  the 
shelter  of  tree-growth  attack  and  destroy  heather. 

Heather  reproduces  itself  chiefly  by  seed  carried  by  the 
wind,  and  less  by  suckers  and  shoots. 


Proterfive  Measures. 

i.  Maintain  a  close  forest  growth. 

ii.  Graze  the  heather  down  by  sheep,  but  this  can  be  done 
only  as  long  as  the  heather  is  young  and  tender.     Old,  tough 
heather  will  be  eaten  by 
sheep  only  as  a  last  re- 
source ;   they  will   prefer 
young  forest  plants. 

iii.  Cut  down  or  mow 
the  heather,  specially 
strong  scythes  being  used 
for  the  purpose.  This 
should  be  done  either 
early  in  spring  or  late  in 
summer,  in  order  to  keep 
the  soil  somewhat  pro- 
tected against  the  heat  of 

summer  and  the  winter's       «  /;  =  4  inches;    c  rf  =  10  inches  :    \a  =  60°. 

cold.      The  material  may 

be  used  as  fuel,  thatch  or  litter,,  or  made  into  brooms. 

iv.  Burn  the  heather  in  situ.  This  may  be  done  when 
there  are  no  forest  plants  in  it  the  destruction  of  which  should 
be  avoided,  or  immediately  after  a  coppice  felling.  Fire-traces 
of  sufficient  width  should  be  made  around  the  areas  to  be 
burned,  and  the  burning  should  be  done  on  dry,  still  days  in 
March  or  April,  the  fire  being  lighted  to  leeward,  or  downhill, 
and  closely  watched. 

V.  The  ground  may  be  stripped  of  sods  containing  the  roots 
of  the  heather,  and  a  crop  of  oats  or  rye  produced,  if  advisable, 
before  planting  it  up  with  Scots  pine.  The  mineral  soil  must  be 
exposed,  so  that  the  plants'  roots  are  not  in  the  sour  humus. 
The  instrument  shown  in  Fig.  197  is  used  for  this  purpose.. 
If  there  is  a  superficial  pan  it  should  be  pierced. 

F.P.  D  A 


Fig.  197 
4  inches  ;    c  d 


402  I'ROTECTION   AGAINST    PLANTS. 

e.  Birch. 
The  two  species  of  birch  {Betula  alha,  L.,  and  B.  piihcscens, 
Ehrh.)  ascend  to  5,000  ft.  The  former  is  indifferent  as  to 
soils,  and  the  latter  prefers  boggy  ground.  They  are  sometimes 
hurtful  in  coniferous  forests,  as  their  hard,  whip-like  branches 
break  off  the  tender  spring-shoots  of  conifers.  Owing  to  their 
rapid  growth  when  young  they  may  be  also  prejudicial  to 
young  oak  plants,  but  may  act  as  useful  temporary  nurses  to 
the  latter  against  frost  and  drought.  As  birch  has  a  number  of 
coUum-buds,  it  should  be  cut  below  the  level  of  the  soil.  It 
does  not  usually  produce  suckers. 

/.   Other  Lif/hfdema?i(/iiiff  Weeds. 

The  best  remedy  for  the  remaining  lightdemanding  weeds 
is  to  effect  natural  regeneration  of  the  wood,  or  to  replant  it, 
if  clear-cut,  as  soon  as  possible.  They  are  St.  John's- wort 
{Ilij^ycricum)  ;  balsam  {ImjKiticns  NoU-me-tangere,  L.),  which 
grows  in  damp,  fertile  soil,  in  masses  often  a  yard  high  and 
over  large  areas  ;  willowherb  {Epilobium  cwf/nstifoUuin,  L.)  on 
similar  soil,  the  seed  of  which  appears  to  remain  latent  for  a 
long  time,  and  is  carried  far  and  wide  by  the  wind ;  groundsel 
{Seuecio),  springing  up  in  masses  on  sandy  soils,  the  seed 
carried  far  by  wind  (these  plants  also  act  as  hosts  to  parasitic 
fungi);  hawkweed  (Ilieracium)  ;  Atrojm  Belladonna,  L.,  on 
fertile  damp  soil  in  shady  mountain  forests  of  Europe  and 
Asia  (Himalayas),  is  very  poisonous  :  foxglove  {DuiitaUs)  may 
grow  in  such  masses  that  the  hill-side  appears  red,  both 
species,  I).  pHrpurea,  L.,  and  the  yellow  one,  D.  f/randi flora, 
which  is  not  indigenous  in  Britain,  are  poisonous;  Verhascnm, 
four  species  found  on  dry,  stony  ground  ;  nettles  {Urtica  nrens, 
L.),  an  annual,  and  the  perennial  nettle,  with  strong  rhizomes 
{U.  dioica,  L.),  are  frequently  troublesome  in  forest  nurseries; 
wood-rush  {TAizida),iouY  species  common  in  mountain  forests. 

Grasses  deserve  a  separate  paragraph.  The  most  common 
injurious  kinds  are:— Species  of  bent-grass  {Agrostis);  Aira 
caesjntosa,  L.,  and  A.flexuosa,  L. ;  Mclica  cdiata,  L. ;  sheep's 
fescue  {Fesiuca  ovina,  L.),  and  other  species  of  fescue  ;  couch- 
or  twitch-grass  (Ar/rojii/rum  {Triticum)  repens,  Beauv.)  ;  lyme- 
grass  {Khimus  arrnarius,  L.) ;  mat-grass  {Nardus  siricta,  L.); 


BRAMBLES.  403 

spreading  millium  {Millinm  effasnm,  L.).  Grasses  with  fairly 
broad  leaves  grow  on  deep,  moist,  fertile  soil — they  are  termed 
Ilaitu/mser,  in  German.  AiHjeir/rnser  is  the  term  applied  to 
narrow-leaved  grasses,  that  grow  on  shallow,  dry  and  poor  soil. 

The  damage  due  to  a  dense  growth  of  grass  is  of  several 
kinds :  the  soil  may  become  matted  with  its  roots,  which  may 
prevent  the  seed  of  forest  trees  from  reaching  the  ground  ; 
young  growth  may  be  choked,  the  soil  dried  up,  or  moisture 
kept  in,  and  frost  increased  ;  damage  may  also  be  done  by 
mice  and  insects  which  shelter  in  the  grass.  When  grass 
grows  densely,  it  is  a  sign  that  the  forest  is  too  thin  and 
admits  too  much  light.  Twitch  flourishes  in  sandy  soils, 
creeping  in  all  directions  through  the  soil  and  filling  it  with 
rhizomes ;  it  may  even  penetrate  roots  of  living  plants,  and 
thus  interfere  with  their  growth. 

Weedy  places  may  be  treated  as  already  stated  for  heather, 
and  are  best  recruited  by  means  of  transplants.  Twitch  is  got 
rid  of  by  repeated  ploughing,  and  by  collecting  and  burning  its 
rhizomes ;  three  years'  grazing  on  land  where  it  grows  is  very 
useful,  as  finer  grasses  then  gradually  replace  it. 

In  tropical  and  sub-tropical  countries,  the  dense  growth  of 
grass,  frequently  exceeding  six  feet  in  height,  is  one  of  the 
most  serious  impediments  to  forestry.  Such  grassy  tracts  are 
burned  annually,  the  fires  extending  for  miles,  and  wherever 
the  grass  borders  on  forests,  or  in  the  form  of  savannah  is 
intermixed  with  thinly  stocked  trees,  danger  from  lire  occurs 
during  every  dry  season. 

2.  Ilalf-shadebrarers. 

These  are  all  woody  plants,  except  ferns  and  mosses. 

(a)  Blackthorn  {Prniius  spinosa,  L.)  is  common  on  moist, 
loamy,  and  clay  soils,  and  on  marls,  and  ascends  to  3,000  feet 
in  mountains.  It  stands  frost  better  than  hawthorn,  and 
replaces  it  for  hedging  in  very  frosty  localities.  It  sends  out 
roots  and  suckers,  and  has  a  spreading  root-system,  and  does 
much  harm  in  regeneration  areas  and  among  coppice.  It  is 
best  to  dig  it  up  by  the  roots  in  clearings,  or  cut  it  back 
several  years  before  the  coppice  is  felled. 

{h)  Bramble  {Ruhus  fruticoms,  L.).      There  are  numerous 

D  D  2 


404  PROTECTION    AGAINST    PLANTS. 

varieties  of  this  species,  termed  blackberry  or  dewl)erry 
bushes,  the  latter  (R.  caesium,  L.)  growing  in  moister  localities 
than  the  common  blackberry,  which  prefers  well-drained  soils 
and  hedgerows. 

Brambles  frequently  cover  large  areas  in  fresh  and  moist 
soils,  sending  out  new  suckers  every  year.  To  keep  down 
these  widespread  pests  of  the  forester,  seeding-fellings  should 
be  dark.  Aduiission  of  cattle  is  also  useful.  In  case  there  ])e 
a  dense  growth  of  brambles  on  the  ground  it  should  be 
trampled  down  round  plants  that  require  protection,  or  be 
beaten  down  with  a  billhook.  Brambles  should  be  cut  as  little 
as  possible,  as  this  only  increases  the  production  of  suckers. 
Plants  which  they  are  crowding  should  be  set  upright,  and 
their  branchlets  placed  over  the  brambles.  If  this  be  done 
early  in  the  summer  then  little  will  be  needed  in  tlie  autumn,  but 
it  may  be  necessary  to  repeat  the  operation  the  succeeding 
year ;  i)y  the  second  winter,  the  plants  will  probably  get  out  of 
reach  of  the  brambles.  Cutting  or  digging  up  the  brambles 
is  expensive,  and  not  so  effectual  as  the  above  procedure. 
"Where  a  reproduction  area  is  overgrown  with  brambles,  and 
there  is  little  natural  regeneration,  it  will  be  better  at  once  to 
plant  up  the  area. 

((■)  Raspberry  {Riihus  Idaeus,  L.).  This  grows  chiefly  on 
fertile  but  stony  soils  rich  in  humus.  Its  habit  is  straight, 
and  it  does  not  produce  such  dense  growth  from  suckers  as 
the  bramble,  but  may  become  dangerous,  and  should  then  be 
treated  similarly  to  the  latter.  Grazing  has  a  very  repressive 
effect  on  the  growth  of  raspberry  canes. 

(i.  Hawthorn  {Crataef/iis  Oxyarantha,  L.). 
Hawthorn  is  not  particular  about  locality,  and  is  widely 
spread  up  to  altitudes  of  3,000  feet.  The  rich  shoots  and 
extensive  root-system  of  this  slow-growing  shrub,  which  attains 
a  height  of  20  feet,  are  destructive  to  young  conifers,  but  in 
forests  open  to  grazing  it  protects  oak,  ash,  maple,  and  other 
broadleaved  trees  until  they  have  grown  above  it,  when  it 
forms  a  thorny  defence  around  them  until  they  are  too  large 
to  be  injured  by  cattle.  It  also  forms  capital  hedges,  bearing 
trimming  well,  and  slielters  the  nests  of  many  useful  birds 


FOREST    WILLOWS.  405 

from  small  caniivora  and  otlier  enemies.  Where  it  is  harmful 
to  yom:g  growth,  it  should  he  dug  up  or  cut  hack  in  cleanings 
and  thinnings.  Various  thorny  hushes  in  India  similarly 
afford  great  protection  to  hamhoos  and  other  valuahle  species 
in  grazed  forests. 

e.  Other  Shrubs  and  Bushes. 

The  wild  gooseherry-hush  {Ribes  Grossularia,  L.),  elder 
(Sambucus),  guelder  rose  {Viburnum  Opulus,  L.),  wayfaring 
tree  (F.  Lantana,  L.),  the  spindle  tree  {Euonymus  europaeus,  L.), 
and  privet  {Ligustruui  vulgare,  L.)  are  widespread,  the  latter 
and  Viburnum  Lantana,  L.,  chiefly  on  calcareous  soils  in  hills. 
None  of  these  plants  are,  however,  particularly  hurtful  to 
young  forest  growth,  except  the  herbaceous  dwarf-elder 
{ScDubucus  Ebulus,  L.),  which  grows  in  masses  from  rhizomes 
in  damp  places.  Daphne  Mezcreum,  L.,  is  a  small  shrub 
growing  in  hilly  and  mountain  woods  on  damp  soils,  and  is 
highly  poisonous. 

/.  Forest  Willows. 

Sallow  {Salix  Caprea,  L.)  flourishes,  especially  in  beech 
woods,  on  fresh  §oils  in  plains  and  hills,  but  will  also  grow  on 
dry  soil  and  in  mountains  up  to  5,500  feet,  attaining  at  times 
the  dimensions  of  a  small  tree  ;  it  sends  out  numerous  stool- 
shoots,  but  has  a  shallow  root-system,  so  that  it  may  be  easily 
pulled  up  by  the  hand,  as  well  as  the  other  willows  mentioned 
below.     Its  heartwood  is  bright  red. 

Sallow  takes  root  anywhere,  even  on  exposed  rock,  and 
grows  about  six  feet  in  height  in  a  single  season,  so  that  it  is 
extremely  injurious  in  young  plantations. 

Sulix  cincrea,  L.,  a  variety  of  the  sallow,  is  a  smaller  plant 
of  a  shrubby  nature;  it  sends  out  suckers  on  damp  soils  and 
along  water  courses  ;  ascends  to  3,000  feet. 

Salix  aurita,  L.,  resembles  the  sallow  in  its  habit,  but  sends 
out  suckers;  it  ascends  to  5,000  feet,  indifferent  to  wet  or  dry  soils. 

Salix  repens,  L.,  is  a  small,  straggling  bush,  growing  chiefly 
on  turfy  and  heather  land,  and  also  near  swamps  ;  ascends  to 
3,500  feet. 

All  these  willows  when  hurtful  to  forest  growth  should  be 
cut  back  or  pulled  up  in  cleanings  and  thinnings. 


406  I'ROTECTIOX    AOAINST    PLANTS. 

//.  Aspon  {Popuhiri  trenmhi,  L.). 

Aspen  is  a  tree  which  is  disseminated  throughout  Europe, 
except  in  the  extreme  south,  up  to  70°  N.  latitude,  and  5,000 
feet  altitude  ;  it  is  often  very  hurtful  to  valuable  forest  plants 
owing  to  its  rapid  growth  and  abundant  production  of  suckers. 
The  roots  of  a  felled  aspen,  which  spread  far  from  the  stump, 
close  to  the  surface  of  the  ground,  remain  dormant  for  years 
after  tlie  parent  tree  has  been  removed ;  they  then  send  up 
numerous  suckers  from  adventitious  buds  after  the  wood  in 
which  the  aspen  formerly  grew  has  been  cleared.  The  aspen 
is  not  particular  as  regards  soil,  but  can  grow  on  cold,  wet 
soils,  and  is  frequently  found  in  frosty  localities,  as,  for 
instance,  on  the  London  clay  in  Epping  Forest. 

The  aspen  is  also  a  host  for  an  injurious  fungus,  ISIclampsoya 
Tremulac,  TuL,  which,  in  the  forms  M.  Plnitorqua,  Eostrup., 
and  M.  Laricis,  Harlig,  attacks  pines  and  larch,  and  will  be 
described  further  on  (pp.  44-4,  469). 

Cutting  down  the  suckers  is  of  little  avail,  nor  is  extracting 
the  stumps  and  longer  roots  of  felled  trees,  but  girdling  a 
standing  tree  gradually  dries  it  up  and  in  about  two  years 
prevents  the  formation  of  suckers.  The  tree  may  also  be  felled 
about  three  feet  above  the  ground,  and  the  slump  barked. 

h.  Bilheny  (Vaccinium  Myrtillus,  L.). 

This  is  a  small  shrub  attaining  10  inches  in  height,  and 
growing  throughout  Europe  up  to  5,000  feet  altitude,  in  masses, 
on  fresh,  damp,  and  even  somewhat  sour  soil.  Its  seeds  remain 
for  two  seasons  in  the  ground  before  germinating.  It  may  also 
be  found  on  dry  sandy  soils,  but  not  on  calcareous  ones.  It 
prefers  a  slight  shade,  especially  of  pines.  When  it  appears  in 
masses  it  denotes  insufficiency  of  stock  and  deterioration  of 
the  soil,  and  the  surface-soil  becomes  choked  with  its  roots.  Its 
berries  are  valuable  for  making  alcohol  and  preserves. 

The  cowberry  {Vaccinium  Vitis-Idaea,  L.)  is  an  evergreen 
plant  attaining  8  inches  in  height,  and  growing  on  loose, 
damp,  sandy  soils  in  high,  cool  places  ;  it  is  gregarious,  and  has 
a  distribution  similar  to  that  of  the  bilberry,  growing,  however, 
in  moibter  soil  than  the  latter.  A  dense  growth  of  either  of 
these  species  hinders  natural  regeneration  and  increases  the 


FERNS.  407 

difficulty  of  artificial  restocking.  There  is  then  no  alternative 
but  to  take  up  these  plants  in  sods,  beat  off,  in  sitti,  all  the  soil 
attached  to  their  roots,  and  remove  them.  The  cowberry  plant 
is  also  the  host  of  a  fungus  that  attacks  silver-fir  (p.  419). 
Planting  is  better  than  sowing  where  bilberries  prevail,  and 
spruce  is  the  best  species  to  plant  on  soil  that  produces  them. 
V.  ulighiosum,  L.,  is  found  on  swampy  land  and  mountain- 
tops,  and  the  cranberry  (T'.  Oxycoccos,  L.)  in  patches  on 
peaty  soils.     Both  species  are  unimportant  to  the  forester. 

7.   Ferns. 

The  commoner  kinds  of  ferns  found  in  forests  are :  Poly- 
2)odium  vuUjare,  L,,  Beech  fern  {P.  Phccjopteris,  L.),  Male 
fern  {Nephrodium  Filix-mas.,  Hooker),  Lady  fern  {Aspleniuni 
Filix-faemina ,  Bentham),  and  Bracken  {Pteris  aquilina,  L.). 

The  above  prefer  damp  and  stony  ground,  and  their 
appearance  denotes  a  fertile  soil,  as  well  as  a  slight  opening 
out  of  the  leaf-canopy.  They  spread  above  and  below  ground 
often  to  the  prejudice  of  young  forest  plants,  by  causing 
excessive  moisture,  and  depriving  them  of  light,  and  by  being 
pressed  down  on  them  in  a  rotting  state  in  winter  by  the 
snow.  This  frequently  kills  lightdemanders.  Bracken  often 
covers  wide  stretches  of  deep  sandy  land,  but  its  sub- aerial 
parts  are  extremely  sensitive  to  frost. 

In  the  case  of  bracken,  the  best  plan  is  to  knock  off  the  soft 
young  shoots  in  early  summer,  which  can  be  done  easily  with 
a  stick  before  they  have  unrolled.  This  injures  the  rhizomes, 
so  that  only  weakly  shoots  are  produced,  which  may  be  knocked 
off  or  neglected.  Dried  bracken  is  largely  used  in  England  and 
elsewhere  for  litter,  and  in  the  Forest  of  Dean,  repeated  early 
cutting,  in  August,  instead  of  October,  has  greatly  weakened 
the  rhizomes  of  the  plant,  so  that  only  a  short  weak  crop  is 
produced,  as  compared  with  that  in  the  Windsor  and  New 
Forests,  where  it  is  cut  later  in  the  autumn. 
Jr.  Mosses. 

Two,  out  of  42  species  of  Polytrichum,  are  hurtful  mosses 
common  in  forests:  Pob/tricJuini  commune,  L.,  and  P.  juniper- 
inn  m,  Hedw.  The  former  produces  dense  convex  tufts  in  damp 
places,  and  the  latter  on  drier  ground.     These  tufts  may  be 


408  PROTECTION    AGAINST    PLANTS. 

distinguished  at  a  distance  by  their  darker  green  colour  froni 
the  paler  and  branchy  mosses,  Hi/pnum  and  llylocominm,  which 
form  a  useful  soil-covering  in  forests.  They  are  chiefly  found 
in  high  forest,  and  especially  in  spruce  woods,  and  do  harm 
by  favouring  excessive  moisture  in  the  ground  and  injuring 
the  germination  of  seedlings.  The  tufts  should  be  turned 
over  and  broken  up. 

The  branchy  mosses  that  form  the  normal  soil-covering  in 
coniferous  woods  (about  123  species)  may  become  so  thick,  as 
to  render  the  soil  too  moist  for  the  germination  of  naturally 
fallen  seed.  Or  they  may  be  tall  enough  to  overshade  natural 
seedlings.  In  such  eases,  the  mossy  covering  should  be 
removed,  so  as  to  expose  the  mineral  soil. 

3.  Shadehearim)  Weeds. 

These  are  all  woody  plants.  Alder-buckthorn  (RJiamnus 
Frangula,  L.)  is  common  throughout  Europe  on  damp  ground, 
and  chiefly  in  lowlands ;  it  produces  many  suckers,  and  is 
spread  much  by  birds  which  eat  the  berries.  It  is  used  for 
gunpowder-charcoal. 

The  common  buckthorn  (i?.  catharticus,  L.)  is  a  thorny 
shrub  with  spreading  roots  and  many  suckers,  found  on 
similar  soil  to  the  former,  and  along  banks  of  streams. 

Both  kinds  are  hosts  of  a  fungus  destructive  to  cereals 
(p.  418).     They  may  be  dug  up  during  cleanings. 

Dogwood  {Cormis  sanfiuinca,  L.),  on  fertile  moist  soils, 
ascends  to  2,600  feet  in  mountains,  and  sends  out  numerous 
stool  shoots.  The  wood  is  used  for  skewers,  and  was  formerly 
emi)loyed  for  arrows. 

Holly  {Ilex  Aqnifol'mm,  L.),  a  large  evergreen  prickly  shrub 
or  small  tree,  found  chiefly  on  good  damp  loam  or  loamy  sand  : 
it  coppices  well.  Where  it  abounds  it  is  possible  to  plant  only 
strong  transplants  between  the  holly  bushes,  and  the  latter 
need  constantly  cutting  back,  until  they  are  no  longer 
dangerous.  Holly  makes  excellent  hedges,  but  requires 
plenty  of  humus.  It  is  calciphobous  like  sweet-chestnut,  and 
attains  a  height  of  80—40  feet  in  Britain,  but  on  the  Continent 
chiefly  a  bushy  undergrowth  in  forests. 

Holly  (German,  Ilidst)  was  considered  a  lioly  or  preservative 
plant,  i)reservingone  from  evil  influences,  hence  its  use  in  house 


FOREST    WKEDS   OF    WET    PEATY    SOIL.  409 

and  church  decorations  at  Christmas,  and  as  a  sign  hefore  a 
public-house.    Birdlime  is  made  from  its  cortical  parenchyma. 

Butcher's  broom  (Biiscns  aculeatus,  L.)  grows  in  dense  woods 
in  the  south  of  England,  it  is  unimportant  for  the  forester. 

Nightshade  {Solan urn  Dulcamara,  L.),  a  small  shrub  growing 
in  shady,  damp,  low  lands  and  along  banks  of  streams,  climbing 
up  to  10  feet  in  height  on  pollard  willows  and  osiers.  This 
plant,  as  well  as  S.  nigrum,  L.,  which  chiefly  grows  along  road- 
sides, is  highly  poisonous. 

Common  juniper  {Jiinipcrus  commioiia,  L.)  is  a  coniferous 
shrub  widespread  all  over  Europe,  in  plains  and  mountains, 
ui)  to  6.000  feet  in  the  Alps.  It  is  very  hardy  and  indill'ereut 
to  soils.  It  spreads  owing  to  thrushes  which  swallow  the  berries. 
Grows  well  in  the  open  and  also  in  dense  pine  woods.  This 
species  and  J.  Sabina,  L.,  are  hosts  of  fungi  that  attack 
Pomaceae  (p.  419).  Should  be  cut  down  or  pulled  up  when 
dangerous  to  young  growth. 

4.  Forest  Weeds  of  Wet  Peaty  Soil. 

To  this  group  belong  the  numerous  species  of  the  following 
genera. 

Rushes  {Jinicus,  L.),  (Scirpus,  L.),  Cottongrass  {Eriopltorum, 
L.),  Sedges  {Carex,  L.),  Eeeds  {Calamagrostis,  Adams),  and 
Marestail  {Equisetitm,  L.). 

All  these,  except  the  last,  may  be  termed  Jialf-grasses,  and 
they  all  form  sour  herbage,  and  are  chiefly  found  in  lowlands, 
or  on  peat,  and  are  somewhat  lightdemanding.  Equisetum 
arvense,  L.,  is  a  troublesome  weed  in  somewhat  wet  sandy 
loam  in  forest  nurseries,  its  rhizomes  being  deep  down  in  the 
soil,  and  their  extraction  requiring  deep  trenching. 

Sphafiiium.  Several  species  of  this  peat-moss  exist  and  grow 
chiefly  in  the  open,  in  opposition  to  Pohjtrichum,  which  grows 
under  cover.  They  are  most  dangerous  mosses,  producing 
peat  and  swamps,  and  rendering  the  soil  unsuitable  for  forest 
growth.     They  discharge  their  spores  with  an  audible  sound. 

The  invasion  of  sour  herbage  and  peat-mosses  is  best  kept 
down  by  maintaining  the  leaf-canopy.  If  a  swamp  has  been 
formed  it  must  be  drained  ;  sometimes,  however,  on  flat  land, 
with  a  tendency  to  swampiness,  as  shown  by  the  presence  of 


410 


PROTECTION    AfJAINST    PLANTS. 


these  weeds,  after  a  forest  crop  has  been  cleared,  ash  and 
alder  should  be  planted  instead  of 
oak  and  beech,  the  swampiness  dis- 
appearing after  the  forest  growth  has 
been  reconstituted. 


5.  Lianes. 

The  first  three  European  lianes  given 
are  woody,  and  the  others  herbaceous. 
The  shoots  of  all  lianes  should  be  cut 
repeatedly  below  the  ground  till  no 
more  appear.  There  is  no  necessity  to 
unwind  the  twiner,  unless  it  is  a  woody 
species,  as  it  soon  dries  up  after  being 
cut  from  the  root. 

(a)  Traveller's  joy  {Clonatia  Vitalha, 
L.)  is  widesj)read  throughout  Europe, 
chiefly  on  hills  and  mountains;  it  is  a 
half-shadebearer  and  attains  a  height 
of  20  feet,  climbing  up  stems,  bushes, 
and  rocks.  The  shoots  may  strike  root 
whereever  they  rest  on  soil,  and  the 
plant  sometimes  grows  in  masses  and 
is  dangerous  to  young  forest  plants. 

{h)  Honeysuckle  or  woodbine  {Loni- 
ceraPcrichjmennm,  L.),a  twiner  growing 
in  hedgerows,  edges  of  woods,  and  inside 
woods  throughout  Western  Europe  ;  it 
is  found  on  damp  soil  and  chiefly  in 
lowlands.  A  half-shadebearer,  twining 
round  saplings  to  a  considerable  height, 
and  thus  producing  misshapen  spiral 
stems  as  in  Fig.  198.  If  no  suitable 
stems  are  available,  it  covers  the 
ground  and  the  herbaceous  plants 
growing  on  it.  It  does  much  damage 
to  valuable  saplings  in  coppice-with- 
standard  and  also  to  larch  plantations.  L.  CapriJoUnm,  L., 
with  connate  upper  leaves,  is  common  in  Southern  Europe, 


Fif?.  198.  —  "Woodbine 
climbing  spirally  round  u 
young  spruce  and  partly 
enclosed  by  the  wood  of  the 
latt.r. 


COMMON   IVY.  411 

and  has  become  wild  in  certain  localities  further  north ;   it 
has  similar  habits  to  the  former, 

(r)  The  common  Ivy  {Jlcdera  Helix,  L.)  is  widely  distributed 
and  extends  over  the  milder  parts  of  Europe,  Northern  Asia, 
into  India  and  Japan,  and  North  Africa.  It  climbs  trees,  rocks 
and  walls  by  means  of  its  adhesive  rootlets,  which  however 
suck  no  nutriment  from  the  host  on  which  it  is  growing,  but 
merely  support  the  ivy.  The  smaller  forest  variety  is  said  not 
to  flower,  and  sometimes  covers  the  soil  of  a  forest.  Ivy  grows 
away  from  the  light,  except  its  blossoming  shoots,  which  have 
undivided  leaves  and  grow  towards  the  light.  Matthieu* 
considers  ivy  hurtful  to  forest  trees  by  interfering  with  the 
passage  of  the  sap,  and  by  covering  the  crowns  of  trees  with 
its  foliage,  and  it  certainly,  at  times,  like  the  honeysuckle, 
constricts  oak  and  other  saplings  and  poles.  The  ivy, 
however,  rarely  ascends  higher  than  the  middle  of  the  crown 
of  a  growing  tree,  and  may  be  useful  in  preventing  the  forma- 
tion of  epicormie  branches  on  standards.  It  dries  the  surface 
of  walls  on  which  it  is  growing,  and  also  the  soil  when  creeping 
over  it.  Ivy  sometimes  attains  very  large  dimensions,  a  plant 
at  Montpellier  being  450  years  old  and  9f  feet  in  girth. 

((/)  Bindweed  {Convolvulus,  L.) :  C.  arvensis,  L.,  chiefly 
found  in  fields  and  waste  places ;  C.  sepinm,  L.,  in  hedges  and 
thickets.  Both  species  are  extremely  troublesome  in  nurseries 
and  in  osier  beds,  as  their  deeply  seated  rhizomes  fill  the 
ground,  and  their  shoots  twine  round  and  bear  down  the  young 
plants. 

To  deal  with  these  pests,  the  ground  when  bare  should  be 
trenched,  and  the  soft  whitish  rhizomes  of  the  bindweed 
collected  and  burned.  It  is  dilVicult  to  do  this  thoroughly,  as 
the  roots  go  down  to  18  inches  in  the  soil. 

Black  bindweed  (Poli/noiium  Convolvulus,  L.)  is  chieHy 
found  in  fields  and  waste  places,  and  has  similar  habits  to  the 
above.  It  is  however  an  annual  plant  and  injurious  only  in 
nurseries. 

{(•)  Wild  hop  {Ilumulus  Lupulus,  L.).  The  hop  is  found  in 
damp  places  in  lowlands ;  it  twines  from  right  to  left  up 
woody  plants  and  drags  them  down.     The  rootstock  alone  is 

*  Flore  foresti^re,  1897,  p.  200. 


412 


PROTECTION  AGAINST  PLANTS. 


perennial.     Hops  are  injurious  in   osier  beds  and  in   alder 
coppice.     They  should  be  dug  up. 

6.  Parasitic  lihanerogams. 
a.  Misfleloe  (Vt'scum  album,  L.). 

This  interesting  plant  lives  as  a  semi-parasite  (obtaining 
carbon  from  the  air,  but  water,  nitrogen,  and  mineral  matter 
from  the  sap  of  its  host)  on  many  conifers  and  broadleaved 
trees,  and  chiefly  on  their  branches.     The  hosts,  or  trees  on 

which  it  lives,  are,  viost 
frequently,  the  apple  tree, 
both  wild  and  cultivated 
varieties;  next,  the  silver- 
fir  ;  frequently,  birches, 
poplars  (except  aspen),  limes, 
willows,  Scots  pine,  moun- 
tain-ash, and  hawthorn ; 
occasionally,  robinia,  maples, 
horse  -  chestnut,  hornbeam, 
and  aspen. 

It  is  very  rarely  found  on 
oaks,  but  has  been  observed 
on  pedunculate  oak  at  Thorn- 
bury,  Gloucestershire,  and 
elsewhere  in  Europe,  also 
on  Quercus  coccinea,  Mccnch., 
and  Q.  imlustris,  Manich. 
The  alders,  beech  and  spruce 
appear  to  be  always  free  from  mistletoe,  and  it  very  rarely 
attacks  pear-trees. 

It  is  commoner  in  Southern  Europe  than  in  the  North,  and 
is  extremely  abundant  where  cider  is  made.  In  the  N.-W. 
Himalayan  districts,  it  is  frequently  found  on  apricot  trees, 
which  are  the  commonest  fruit-trees  there. 

Its  white  berries  are  eaten  by  birds,  chiefly  by  the  missel- 
thrush  {Turdus  riscirorus,  L.),  and  the  seeds  are  either  rubbed 
by  the  beak  against  branches  of  trees,  or  voided  on  to  them ;  the 
seeds,  owing  to  the  viscous  nature  of  the  pulp  surrounding 
tliem,  then  become  attached  to  the  branches. 


riihrion,    L.,    attacked 
{i)i).     [Itcduccd.) 


MISTLETOE. 


413 


The  plant  sends  down  modified  roots  (hau^oria),  termed 
sinkers,  through  the  bark  as  far  as  the  wood.  It  also  emits  lateral 
shoots,  or  cortical  roots,  into  the  bast,  chiefly  in  the  longitudinal 
direction  of  the  branch  of  its  host,  and  these  do  not  grow-  down 
into  the  wood.  The  growing 
point  of  the  cortical  root  ob- 
tains nourishment  from  the 
bast,  but  does  not  injure  the 
cambium  ring ;  the  cortical  root 
sends  down  as  far  as  the  wood 
fresh  sinkers,  which  also  absorb 
nourishment :  upward  shoots 
from  it  pierce  the  bark  into 
the  air ;  these,  like  the  original 
sub-aerial  shoots,  ramify  and 
become  covered  with  foliage, 
and  bear  fruit.  The  haus- 
toria  elongating  outwards  like 
medullary  rays  become  deeply 
embedded  in  the  wood  of  the 
host  by  the  grow^th  of  the 
latter ;  thus  the  older  part  of 
the  cortical  root  gets  gradually 
driven  outwards  by  the  growth 
of  the  bast  until  it  is  cut 
off  by  the  formation  of 
corky  tissue  within  the  bast, 
when  it  eventually  falls  off 
with  the  older  bark.  The 
sinkers  thus  losing  connection 
with  the  living  mistletoe  die 
inside  the  wood  by  which  they 
are  gradually  surrounded.    As 

they  are  formed  of   soft   tissue,  they  soon   decompose    and 
eventually  disappear,  leaving  a  series  of  holes  in  the  wood. 

This  dying  of  the  cortical  root  is  quicker  in  the  Scots  pine 
than  in  the  silver-fir  owing  to  the  earlier  formation  of 
rhytidome,  or  true  bark,  in  the  former. 

The  portion  of  the  host  to  which  the  mistletoe  is  attached 


Fig.  200  {Afler  Hartig).— Diagram 
representing  the  growth  of  the  cortical 
root  and  sinkers  of  mistletoe.  The 
terminal  point  of  the  cortical  root(c) 
is  close  to  the  wood.  The  growth  of 
bast  (>))  drives  the  cortical  root  nearer 
and  nearer  to  the  outer  bark,  (c)  are 
dead  sinkers,  the  cortical  root  of  which 
has  been  cut  o£E  for  several  years  by  the 
production  of  cork  in  the  bast. 


414 


I'ROTKCTION   AGAINST   PLANTS. 


generally  swells  owing  to  a  supply  of  carbohydrates  being 
absorbed  by  it,  produced  partly  by  the  mistletoe.  Where  only  a 
branch  is  attacked,  the  damage  done  to  forest  trees  is  not  worth 
mention,  but  when  this  extends  to  the  stem,  the  wood  becomes 
technically  injured,  being  no  longer  suitable  for  timber,  and  is 
liable  to  be  broken  by  the  wind. 


Fig.    201.— Silver-fir   («•)   attacked   by   mistletoe    (»i). 

(t)  Annual  shoot  (i)  opposite  leaves  of  latter. 

{Natural  size.) 


Fig.  202.— Silver-fir 
wood  perforated  by 
mistletoe,  the  haus- 
toria  of  which  have 
been  absorbed. 


Extensive  damage  is  thus  sometimes  done  in  old  Scots  pine 
and  silver-fir  forests,  owing  to  neglect  in  removing  infected 
trees  in  the  thinnings ;  nearly  every  tree  in  a  compartment 
may  then  be  attacked  by  mistletoe. 

As  a  remedial  measure,  pruning  off  the  mistletoe  is  useless, 
for  the  cortical  root  sends  out  new  shoots,  which  break 
til  rough  the  bark  of  the  host  and  develop  into  new  plants. 
Tlie  only  effective  plan  is  to  i)rune  off  the  whole  infected  branch 


LORANTHUS    EUROPAEUS. 


415 


and  cover  the  wound  with  tar,  or  to  cut  down  infected  trees  in 
the  thinnings.  For  fruit-trees,  and  in  nurseries,  the  former 
method  shoukl  be  adopted. 

Mistletoe  makes  good  fodder  for  cattle,  and  for  roe- deer  in 
winter.  Steamer  loads  of  it  are  sent  from  NoVmandy  to 
London  for  Christmas  decorations. 

b.  Loirin/I/us  Piiroparus,  L. 

This  species  attacks  chiefly  oaks,  Qucrciis  Cerris,  L.,  Q. 
sessilijiora,  Salisb.,  less 
frequently,  Q.  pcdunculata, 
Ehrh.  and  Castanea  vul- 
garis, Lam. ;  also  lime. 
It  is  found  throughout 
Southern  Europe  and  as 
far  north  as  Saxony,  not  in 
Britain.  It  grows  chiefly 
on  the  branches  of  stan- 
dards over  coppice. 

The  main  difference 
between  the  growth  of 
this  parasite  and  mistle- 
toe,  besides    its   outward 


Figs.  203  and  20i. —Zo)finihns  europaeus,  Jacq.     Fig.  203  rcdiued, 
Fig.  204  natural  size. 


appearance  with  bright  yellow  berries,  is  that  the  lateral 
shoots  of  the  first  haustorium  occur  in  the  cambium  and 
sapwood  and  not  in  the  bast,  and  continue  to  grow  parallel 
to  the  woody  fibres  of  its  host,  sending  out  no  sinkers. 
These  shoots  terminate  in  a  wedge  that  looks  as  if  it  splits 
the  wood  as  it  proceeds,  but  at  the  commencement  of  their 


416 


PROTKCTION  A0AIX8T  PLANTS. 


second  season,  they  can  no  longer  proceed  except  in  the 
cambium,  now  further  outward,  and  therefore  grow  from  a 
new  growing  point  above  the  old  one  ;  this  occurs  at  the 
commencement  of  each  season's  growth,  so  that  a  series  of 
wedge-sliaped  steps  are  produced  in  the  sapwood  of  the  host. 


Fig.  20'). — QiwrcKn  Cn-n^,  1..,  with  two  Loranlhnx 
parasites  (/).  (a)  Swellings  produced  by  Ihe 
parasites,  {li)  Stunted  leader  of  the  oak  which 
will  eventually  die. 


Fig  20G  {All,,  il.tiiu).— 
Loxnithub  cioopaaii,  L. 
(d  Jlaiistoriinn  growing  in 
siipwood.  (x)  Terminal  part 
of  ditto.  (e)  Section  of 
another  haustorium. 


Places  on  the  host  where  the  parasite  is  exposed  to  the  air 
swell  up  into  masses  as  big  as  a  man's  head,  whilst  the  branch 
of  the  host  not  only  suffers  in  growth,  but  frequently  dies. 
The  damage  done  is  therefore  greater  than  by  the  common 
mistletoe.  The  seeds  are  carried  on  to  the  trees  by  birds,  and 
chiefly  l)y  the  missel-thrush.  The  younger  portions  of  the 
shoots  of  this  parasite  absorb  from  its  host  water  and  nitro- 
genous and  mineral  matter,  wliile  it  partially  nourishes  the 
host  with  carliohydrates  formed  ])y  its  own  aerial  branches. 


DODDER.  417 

There  are  in  India  many  species  of  Tjoranthus,  which  grow 
on  various  species  of  forest  trees*  ;  these  they  seriously  injure. 
Fortunately,  infected  trees  are  not  generally  found  except 
along  the  borders  of  a  forest.  Infected  trees  should  be  cut 
out  in  thinnings.  ArccuthohiiLm  Oxycedri,  M.  Bieb.,  is  a  small 
loranthaceous  parasite,  on  Juniperus  excelsa,  M.  Bieb.,  in  the 
N.W.  Himalayas;  also  on  a  juniper  in  the  French  Alps, 
Algeria,  and  Asia  Minor  ;  also  on  several  pines,  in  N.  America. 
It  often  kills  its  host. 

c.  Dodder  {Cuscuta,  Tournef). 

There  are  several  species  of  Cuscuta,  of  which  C.  Epithymum, 
L.,  is  the  commonest  in  Britain,  growing  chiefly  on  furze, 
thyme,  ling,  etc. ;  and  also  on  clover  and  lucerne ;  whilst  C. 
EpiUnum,  Weihe,  chiefly  grows  on  flax;  and  C.  europaea,  L., 
on  hops,  nettles,  vetches,  etc.,  and  also  on  many  trees  and 
shrubs,  such  as  hazel,  willow,  poplar  and  blackthorn. 

The  various  species  of  dodder  germinate  in  the  ground, 
but  speedily  die  unless  they  become  attached  to  weeds  or 
agricultural  or  forest  plants,  on  which  they  climb  and  pierce 
down  to  their  woody  bundles  by  means  of  liaustoria,  or 
sucker-like  roots. 

The  plants  attacked  by  these  parasites  are  killed  or 
weakened,  or  bent  down  by  the  weight  of  the  dodder,  and 
much  damage  is  thus  done  in  India  to  small  forest-  and 
avenue-trees,  and  to  fruit-trees. 

Of  European  forest  plants,  osier-willows  suffer  most,  as  an 
abnormal  growth  is  produced  at  places  where  the  haustoria 
have  pierced  the  cortex  of  the  host,  thus  rendering  the  osiers 
unfit  for  basket  work. 

In  the  case  of  agricultural  crops,  care  should  be  taken  to 
obtain  seed  free  from  dodder-seed.  Where  the  dodder  attacks 
osiers,  the  shoots  with  the  dodder  on  them  should  be  cut  as 
low  down  as  possible,  at  the  beginning  of  the  blossoming 
period  (end  of  June  and  beginning  of  July),  and  forthwith 
burned.     This  operation  should  be  repeated  in  consecutive 

*  Vide  paper  by  G.  M.  Ryan,  "Indian  Forester,"  December,  181t'.),  p.  472 
Lomidhus  longijioriix,  Desrousseaux,  is  very  common  on  teak  standards  over 
coppice  in  the  Bombay  Presidency. 

F.P.  E   E 


418  I'ROTKCTION    AOAINST    PLANTS. 

years,  as  seeds  of  the  dodder  may  remain  2  and  3  years 
dormant  in  the  ground.  Hares  spread  the  infection  by 
swallowing  the  seeds  and  passing  them  undigested  on  to  the 
ground. 

As  dodder  spreads  from  forest  plants,  and  hedgerows  where 
it  is  very  frequent,  to  crops,  its  destruction  is  urgent  from 
motives  of  general  utility. 


7.  Forest   Weeds  acting  as  Hosts  for  Injurious  Fungi. 

The  common  barberry  {Dcrheris  vulgaris,  L.)  is  a  shrub 
widely  spread  over  Europe,  both  in  the  lowlands  and  moun- 
tains, and  generally  along  the  edges  of  forests.  It  grows 
even  on  poor  sandy  soil,  soon  attains  a  height  of  12  feet,  and 
sends  out  its  deep  root-system  in  all  directions.  Barberry  is 
very  hurtful  as  the  host  of  black-rust  {Puccinia  graminis, 
Pers.)  that  attacks  wheat  and  other  cereals,  and  should  there- 
fore never  be  used  to  form  hedges.  Its  use  for  this  purpose 
has  been  prohibited  in  Prussia  since  1880. 

Puccinia  graminis,  Pers.,  forms  yellow  lines  of  sporangia 
on  the  blade  of  wheat  and  other  grasses  which  afterwards 
become  reddish-brown,  and  in  this  way  the  nourishment  of  the 
plants  attacked  is  intercepted  and  the  crop  reduced.  It  lives 
alternately  in  the  form  known  as  Aecidium  Ik'rheridis,  Pers., 
on  species  of  Berheris,  or  Mahonia,  the  spores  of  which  falling 
on  cereals  and  other  grasses  hibernate  as  P.  graminis,  the 
spores  from  which  re-infect  the  barberry  and  so  on.  Another 
form,  crown-rust,  P.  coronata,  Corda.,  which  also  forms  a 
rust  on  cereals,  and  especially  on  oats,  arises  from  Aecidia 
that  form  golden-yellow  swellings  on  Ehamnus  catharticus 
and  It.  Frangida,  the  two  species  of  buckthorn  already 
described. 

Species  of  Udn's  are  the  hosts  of  Cronartium  ribirolum, 
Dietr.,  which  produces  Weymouth  Pine  blister  {Peridermiuni 
Strohi,  Kleb.). 

Species  of  Senecio  harbour  Colcospori^nn  Senccionis,  Fr., 
which  alternates  in  the  form  of  Peridermiuni  Pini  acicola, 
Pers.  (p.  461),  a  fungus  attacking  the  needles  of  Scots  and 
other  pines,  and  described  further  on.     Species  of  Coleosporium 


LIST    OF    FOREST    WKEDS.  419 

growing  on  Euphrasia  and  Tussilago  also  produce  pine-needle 
blister. 

The  aspen  {Popidns  Tremula,  L.)  has  its  leaves  infected  with 
a  fungus,  Melainpsora  pinitorqua,  Eostrup.,  so  that  its  foliage 
may  appear  quite  golden-yellow  in  August,  and  then  rapidly 
fall.  The  sporocarps  of  this  fungus  on  aspen  leaves  eventu- 
ally turn  dark  brown,  hibernating  on  the  fallen  aspen  leaves, 
and  in  the  spring,  the  spores  infect  Scots  pine  and  larch 
with  the  fungi.  The  alternate  forms  (pp.  4-44,  470)  on  pine 
and  larch  will  be  described  in  the  next  chapter. 

Vaccinium  Vitis-Idaea,  L.,  acts  as  host  to  Melampsora 
{Calyptospora)  Gocppertiana,  Kiihn,  which,  growing  on  the 
stem  of  this  plant,  develops  spores  infecting  the  needles  of 
silver-fir  with  Aecidium  columnare,  Alb.  (p.  462). 

Species  of  juniper  form  the  alternate  hosts  of  several 
species  of  Gymnosporangium,  a  rust-fungus  attacking  several 
pomaceous  species : 

GymnosporanijiiLm  davariaeforine,  Jacq.,  infects  the  common 
juniper,  and  its  spores  subsequently  attack  pears,  hawthorns, 
or  whitebeams  {Pynis  Aria,  Ehrh.) 

G.  Sabinae,  Winter,  on  the  common  juniper  and  on  the 
savin  {Juniperm  Sahiiia,  L.),  also  occurs  on  pear  trees. 

G.  confusnm,  Plowr.,  spreads  from  junipers  on  to  pears, 
medlars,  quinces  and  hawthorn. 

G.  junipcrinum,  Winter,  occurs  on  rowan  {Pynis  Aiiciiparia, 
Gaertn.),  and  perhaps  on  apple  leaves. 

Species  of  starwort  (Stcdlaria)  and  Ccrastinin  are  the  hosts 
of  a  fungus  causing  silver-iir  canker  and  witches-broom 
(p.  448). 

The  forester  should  always  look  with  suspicion  on  weeds 
or  shrubs  in  his  forests  that  may  be  infested  with  fungi,  and 
if  the  injuriousness  of  these  fungi  to  agricultural  crops  or 
forest  or  fruit-trees  is  proved,  he  should  if  possible  eradicate 
the  wild  plants  ou  which  they  first  appear. 


K  K 


420  I'ROTECTION    AfiAINST    PLANTS. 

8.  Chissificuttiou  of  Forest  JVecds  accordiucj  to  their  Powers 
of  Injury  to  Forests. 

Hess  has  classilied  forest  weeds  as  very  injurious,  less,  and 
least  injurious.  As  the  amount  of  harm  that  weeds  occasion 
varies  greatly  with  circumstances,  it  would  appear  to  he 
sufticient  to  give  the  following  list  of  the  most  injurious 
forest  weeds : — 

Woody  Plants. 
Broom  (To  conifers). 
Heatlier. 
Brambles. 
Aspen. 
Bilberry. 
Mistletoe. 
Loranthus. 
Blackthorn. 
Forest  Willows. 
Birch. 
Honeysuckle. 

Herbaceous  Plants. 
Grasses. 
Bracken. 
Sphagnum. 
Dodder. 
Bindweed. 
Epilobium. 

And  other  tall  weeds,  when  growing  in  masses. 


421 


CHAPTER   II. 

PROTECTION    AGAINST     FUNGI. 

Section  I. — General  Account.* 

1.  Position  of  Fungi  in  the   Vegetable   World. 

Plants  belonging  to  the  lowest  division  of  cryptogamoiis 
plants — which  is  termed  Thallophyta,  and  includes  among 
other  families  6^/ff('n«  aw^  fungi — have  at  most  only  rudimen- 
tary difYerentiation  into  stems,  leaves,  and  roots ;  and  consist 
of  cellular  tissue,  which  may,  however,  in  certain  cases  become 
hardened. 

Bacteria — termed  also  Sehisomycetes,  or  fission-fungi,  from 
their  habit  of  constantly  dividing  to  form  new  cells,  are  plants 
consisting  of  cells  the  diameters  of  which  are  usually  consider- 
ably less  than  -J^j  of  a  millimetre.  They  are  parasitic  or 
saprophytic  on  organic  substances,  and  under  certain  condi- 
tions may  multiply  enormously  in  the  blood  or  digestive  organs 
of  men  or  animals,  and  cause  highly  infectious  diseases  such 
as  cholera,  malaria,  typhoid  fever,  etc. 

Marshall  Ward  has  published  some  papers  in  the  "  Pro- 
ceedings of  the  Royal  Society"  proving  that  sunlight  is  preju- 
dicial to  the  growth  of  bacteria,  which  cannot  therefore  thrive 
on  or  in  the  young  sub-aerial  organs  of  forest  plants  ;  certain 
bacteria,  however,  according  to  Harfcig,  cause  bulbs  and  potato 
tubers  to  rot,  yet  he  states  that  the  only  disease  in  European 

*  Cf.  'A  Text-lK)uk  of  I'laiit-diseases  caused  by  Cryptogamic  Parasites,"  by  G- 
Massce.     London  :  Duckworth  k  Co.,  1903. 

"Fungoid  Pests  on  Cultivated  Plants,"  by  M.C.Cooke.  London:  Spottis- 
woode  k  Co.,  1906. 

Von  Tubeuf,  Dr.  Karl,  "  PHanzenkrankheiten  durch  kryptogame  Parasiten 
verursacht."  Berlin,  1895.  English  translation  by  \V.  Smith.  Longmans, 
London, 1899. 

Hartig,  K.,  "  Lehrbuch  der  Baumkrankheiten.*'  Berlin,  1H89.  English  trans- 
lation of  earlier  edition  of  above  by  Somerville  and  Marehall  Ward.  Macmillan 
k  Co.,  London,  1894. 

Nisbet,  "The  Forester."     B]ackwoo<l  A:  Sons,  1905.     Vol.  II.,  i)p.  141—187. 


422  PROTKfTION    ACAINST    PLANTS. 

trees  hitherto  ascertained  to  be  due  to  bacteria  occurs  in  the 
case  of  Pinus  halcpcnsis,  Mill. 

By  their  presence  in  the  soil,  bacteria  greatly  assist  vegeta- 
tion by  decomposing  and  dissolving  organic  refuse,  and  the 
fact  that  a  forest  soil  when  exposed  for  some  time  to  the  action 
of  the  sun's  rays  becomes  less  fertile  than  when  it  is  con- 
stantly sheltered  by  trees  is  in  complete  accordance  with 
Ward's  researches. 

As  already  stated,  bacteria,  and  certain  fungi  as  well,  also 
protect  forests  by  killing  insect  pests  in  enormous  numbers. 
The  only  thallophytes  which  cause  serious  injury  to  plants 
are  fungi  that  are  devoid  of  chlorophyll  and  therefore  obtain 
their  nutriment  from  other  dead  or  livi)i(j  organisms.  In 
the  former  case,  they  are  termed  saprophytes  and  in  the 
latter,  imrasHes.  Another  class  of  fungi  obtaining  nourish- 
ment from  humus,  but  becoming  attached  to  and  rendering 
abnormal  the  roots  of  many  trees  and  shrubs,  deserves  notice. 
Fungi  growing  on  the  exterior  of  other  plants  may  be  termed 
epiphytic. 

The  number  of  known  fungi  is  very  great,  over  5,000 ;  here 
only  those  which  affect  the  growth  of  forest  plants  will  be 
considered. 

2.  Classijication  and  Importance  of  Fungi  from  a  Forest 

Point  of  View. 

a.  Sajrrophytic  Funyi. 

As  saprophytic  fungi  live  on  dead  or  dying  organisms,  they 
do  not  cause  disease,  but  follow  or  accompany  an  already 
diseased  condition  of  their  hosts.  Fortunately,  the  majority 
of  known  fungi  belong  to  this  class.  Fungi  that  are  sapro- 
phytic in  certain  cases,  as  J ?7«///arm  ?»(7/('a,  Yahl.,  on  rotten 
stumps  of  l)eech  and  other  broadleaved  trees,  may  be  parasitic 
on  other  trees,  such  as  conifers. 

h.  Parasilir  Funyi. 
Parasitic  fungi  attack  healthy  plants,  and  either  cause  a 
sickly  condition  or  actual  death  to  their  hosts.     Some  parasitic 
fungi  subsequently  become  saprophytic  in  tissues  which  they 
have  killed. 


GENERAL   ACCOUNT   OF   FUNGI.  423 

c.  Epiplnjtic  Futn/i. 

Among  epiphytic  fungi  the  family  Tiihcracei  deserve 
mention,  as  they  sometimes  form  underground  myceha  in 
soils  rich  in  humus,  and  thus  cover  the  roots  of  CupuUferae, 
conifers,  willows,  limes  and  other  plants,  to  the  exclusion  or 
modification  of  their  root-hairs.  This  altered  root  with  its 
matted  coating  of  mycelium  receives  the  name  mycorhiza,  and 
the  fungus  has  the  power  of  absorbing  nutritive  matter  from 
the  soil  and  conveying  it  to  the  roots  of  the  host.  These  fungi* 
do  not  in  any  way  injure  the  plants  on  which  they  grow,  but 
feed  them  more  richly  than  the  plants  can  feed  tliemselves 
by  their  own  root-hairs,  in  the  absence  of  the  fungi.  Edible 
trulHes  belong  to  this  family,  and  are  commonly  found  in  oak 
forests  in  the  South  of  England  and  the  more  southern  part 
of  Europe. 

The  study  of  fungi  should  be  followed  as  carefully  by  the 
fprester  as  that  of  injurious  insects,  although  the  damage 
recognised  as  done  to  forests  by  insects  is  much  greater  than 
by  fungi  and  the  remedies  against  them  are  more  effective, 
it  being  often  difficult,  if  not  impossible,  to  combat  hurtful 
fungi.  As,  however,  no  remedy  can  be  devised  without 
studying  the  causes  of  diseases  which  break  out  among  forest 
trees,  the  importance  of  the  study  of  fungi  injurious  to  our 
trees  must  be  admitted.  The  forester  should  be  able  to  say 
whether  any  fungus  is  the  cause,  or  merely  a  consequence  of 
a  disease  or  injury ;  he  must  know  how  to  observe  phenomena 
in  the  forests,  and  should  hand  over  the  specimens  he  may 
collect  to  be  examined  by  mycologists. 

The  treatment  of  the  question  here  adopted  is  therefore 
purely  from  a  forest  point  of  view.  The  anatomy  and  physio- 
logy of  fungi  should  be  studied,  and  a  knowledge  of  mycology 
is  pre-supposed,  A  few  remarks  on  the  life-history  and  dis- 
tribution of  fungi  are,  however,  advisable,  and  a  short  account 
of  the  structure  of  fungi  cannot  be  dispensed  with. 

3.  Mode  of  Life  of  Fungi. 
Fungi  are  cellular  plants  without  chlorophyll,  and  are  either 
unicellular  or  formed  of  many  branching  elliptic  cells,  as  in 

♦  Sec  Frank's  '■  Lclirbuch  der  Botanik,"  18t)3. 


424  I'ltOTKCTION    AfJAINST    PLANTS. 

yeast,  or  of  elongated  cells  termed  hi/phae  with  apical  growth, 
which  may  remain  undivided  or  become  divided  into  cell-rows 
by  septa,  or  transverse  membranes. 

They  are  best  known  and  classified  by  the  forms  of  their 
reproductive  structures,  which  are  generally  sub-aerial,  as  in 
the  common  mushroom  ;  but  the  mass  of  the  hyphae  grows  and 
spreads  through  living  or  rotten  wood,  in  humus,  or  other 
media,  forming  a  collective  growth  termed  a  nnjrdium.  The 
mycelia  of  fungi  may  consist  merely  of  branching  hyphae,  but 
large  masses  of  mycelium  are  sometimes  formed  in  hollows  of 
rotten  wood,  as  by  Pohjporus  sitlphureus,  Fr. 

The  reproductive  organs  of  fungi  are  often  formed  on  special 
branches  of  the  hj'phae  termed  sporocarps,  certain  cells  of 
which  produce  myriads  of  isolated  cells  or  spores,  which  on 
escaping  into  the  air  or  soil  are  cajmble,  under  suitable  con- 
ditions, of  giving  rise  to  new^  individual  fungi.  Spores  may  be 
produced  either  sexually,  or  asexually  by  division,  the  latter 
mode  being  by  far  the  commoner,  the  spores  thus  formed  by 
the  abscission  of  cells  at  the  terminal  points  of  hyphae  being 
termed  cunidia.  For  an  account  of  the  formation  of  sexual 
spores  {carposporcs)  special  books*  may  be  consulted.  Among 
them  are  certain  thick-walled  spores  termed  oospores,  or 
resting  spores,  w^hicli  are  rich  in  nutriment  and,  unlike 
conidia,  do  not  germinate  as  soon  as  they  are  mature,  but 
may  remain  dormant  for  prolonged  periods,  as  in  Phytophthora 
Fcifji,  Pi.  Hrtz.  Sporidia  are  secondary  spores  produced  by 
promycelium  by  the  germination  of  resting  spores. 

As  a  rule,  conidia  remain  only  for  a  few  days  in  a  condition 
fit  to  germinate  and  produce  new  individuals,  but  they  appear 
in  immense  numbers  in  the  air  or  soil,  are  of  microscopic  size, 
and  are  sometimes  carried  for  miles  by  wind  or  water,  or  even 
by  men  and  animals.  Infection  may  also  be  conveyed  by 
seeds  in  the  case  of  certain  rusts,  which  Dr.  Cook}  says  attack 
seeds,  sucli  as  those  of  celery,  wheat,  or  hollyhock  by 
various  sj^ecies  of  Piiccinia.  The  resting  spores  are  usually 
larger  than  the  conidia,  better  protected  and  richly  provided 

•  Dr.  K.  Goelicl's  "  Outlines  of  Classification  of  Special  Morphology  ot  I'lants." 
Translation  by  H.  K.  F.  Garnscy,  Oxford  Clarendon  Press,  1817.  Do  Ikuy, 
"  Mor|)hology  and  Physiology  of  Fungi,"  etc.,  same  translator  and  publisher. 

t   Gaidenern"  Citron.,  13  May,  VMo. 


GENERAL    ACCOUNT    OF    FUNGI.  425 

with  protoplasm,  and  in  certain  cases  may  remain  alive  up 
to  3  or  4  years.  Conidia  and  carpospores  germinate  when 
they  meet  with  favourable  conditions  of  temperature  and 
moisture ;  it  may  be  laid  down  as  a  general  rule,  that  conidia 
serve  to  reproduce  the  fungi  in  great  numbers,  while  the 
carpospores  carry  on  the  species  over  winters  or  prolonged 
dry  seasons. 

Fungi  do  not  usually  require  the  same  amount  of  heat  as 
the  higher  plants  for  their  development,  and  their  fructifying 
organs  are  usually  most  numerous  in  October.  As  already 
stated,  they  may  be  either  saprophytic  or  parasitic,  while 
some  fungi  are  epiphytic,  living  on  the  epidermis  of  leaves  or 
shoots,  and  merely  piercing  into  it  from  time  to  time  with 
delicate  minute  haustoria,  or  root-like  ramifications  of  the 
hyphae,  which  are  devoid  of  any  root-cap.  The  mycelia  of 
parasitic  fungi  live  on  or  in  the  tissues  of  living  plants  or 
animals,  tiieir  spores  gaining  admission  into  the  former  through 
wounds,  lenticels  or  bark-cracks,  or  through  the  stomata  of 
leaves  or  young  shoots,  or  the  soft  growing  points  of  roots. 
There  they  germinate,  and  emit  tender  thin- walled,  generally 
colourless  hyphae,  which,  when  very  young,  are  filled  with 
protoplasm  ;  but  cell-sap  or  bubbles  of  air  soon  occupy  part 
of  their  lumina,  the  protoplasm  then  merely  lining  the  walls 
of  the.  hyphae  or  passing  into  younger  cells.  Oil  may  also 
be  found  in  the  hyphae,  especially  when  they  pass  through 
tissues  of  the  host  which  are  rich  in  reserve-material.  This 
oil  is  frequently  of  a  golden-yellow  colour,  as  in  many  kinds  of 
rusts  on  leaves  or  shoots. 

The  hyphae  grow  by  their  apices,  and  their  terminal  cells 
are  always  rich  in  protoplasm.  In  the  case  of  parasitic  fungi, 
the  hyphae  may  grow  either  in  an  intercellular  manner  between 
the  tissue  elements  or  in  the  resin-ducts  and  other  intercelkilar 
spaces,  merely  sending  their  haustoria  into  the  lumina  of  the 
tissue-elements,  or,  if  the  hyphae  are  furnished  at  their  apices 
with  a  ferment  capable  of  decomposing  the  cell-walls,  they 
themselves  penetrate  through  the  cell-walls  of  their  host,  and 
thus  pass  from  one  cell  to  another.  As  they  proceed,  the 
younger  cells  of  the  hyphae  procure  protoplasm  from  the  older 
cells,  in  which  eventually  nothing  but  air  is  left. 


426  PROTECTION    AfJAINST    PLANTS. 

Tlie  walls  of  the  hyphae  are  at  first  alwaj's  soft  and  colour- 
less, but  when  older  they  may  be  considerably  thickened  and 
coloured  brown  or  greenish-blue,  as  in  rotten  spruce-  or  beech- 
wood.  Sometimes  the  hyphae  unite  into  compact  bundles  with 
hard  walls,  termed  rhizomorphs,  which  resemble  roots,  and 
serve  to  carry  the  mycelia  through  unnutritious  or  dry  media. 
These  are  very  consj^icuous  in  A rmillarca  mellea,  Vahl.  Hyphae 
also  sometimes  unite  into  small  tuber-like  bodies  termed 
sch'wtia,  which  have  thick  cell-walls,  and  are  richly  supplied 
with  protoplasm  and  oil,  and,  as  in  Ilosellinia  quorina, 
11.  Ilrtg.,  may  remain  for  some  time  dormant  and  resist  desic- 
cation,* but  under  favourable  conditions  develop  new  mycelia 
or  sporocarps. 

In  this  way  the  mycelia  of  parasitic  fungi  live  on  the  tissues 
and  nutritive  material  of  their  host,  and  interfere  with  its 
transpiration  and  assimilation ;  they  also  dissolve  the  cell- 
walls  and  their  contents,  often  causing  lij/pcrt ro2)Jnj  or  excessive 
formation  of  cells,  and  chemical  change  in  the  cell-wall.  In 
the  latter  case,  they  cause  the  death  of  the  host.  Insects 
frequently  attack  trees  which  have  become  weakened  l)y  fungi. 
Eventually  the  fructifying  organs,  which  are  characteristic  for 
each  species  of  fungus,  break  out  on  leaves,  twigs,  bark  or  at 
the  scars  of  dead  branches,  sometimes  through  perforations 
made  by  bark-beetles,  sometimes  on  the  roots  of  the  host,  or 
on  rhizomorphs,  as  in  Armillarea  mellea,  Vahl.  Innumerable 
spores  issue  from  the  sporocarps,  some  of  which  find  suit- 
able resting-places,  and  the  fungus-life  recommences  in  fresh 
hosts. 

Most  fungi  are  very  transitory,  and  their  life  occupies  only 
a  few  months  or  weeks.  In  the  case  of  others,  the  resting 
spores  hibernate,  and  the  mycelia  of  some  fungi  may  live  for 
two,  three,  or  many  years.  Most  of  the  destructive  forest 
fungi  have  the  latter  character.  The  polymorphy  which  exists 
in  the  case  of  certain  fungi  requires  an  explanation  here. 
From  the  spores  of  certain  fungi  the  same  form  does  not 
always  appear,  but  sometimes  one  perfectly  distinct,  unlike 
the  parent  fungus,  and  living  on  a  difTerent  host ;  its  spores 
may  even  produce  a  third  form,  though  eventually  the  original 
fungus  is  reproduced.    Thus,  many  fungi,  formerly  considered 


GENERAL   ACCOUNT   OF    FUNGI.  427 

as  distinct  species,  are  now  recognised  as  being  merely  stages 
in  the  development  of  one  species.  The  most  highly  organised 
of  these  stages,  in  the  case  of  any  species,  is  considered  to  be 
that  which  bears  sexually  fructifying  organs  or  their  equiva- 
lents. Fungi  which  thus  grow  in  dilTerent  forms  on  different 
hosts  are  termed  Jietcroecious ,-  some,  however,  go  through  all 
their  forms  on  the  same  host. 

4.  Distribution  of  Fungi. 

The  spread  of  fungi  is  favoured  by  certain  conditions  of  the 
weather  and  locality.  It  depends  chiefly  on  heat  and  moisture, 
light  being  prejudicial,  many  fungi  growing  in  the  intetior  of 
trees  or  in  the  ground.  Fungi  can  flourish  and  become 
numerous  only  under  suitable  conditions,  so  that  in  damp 
years,  and  especially  in  damp  sheltered  localities,  they  thrive 
better  than  in  dry  years  and  exposed  places.  Thus,  in  a  wet 
June,  Melampsora  pinitorqua,  Eostrup.,  is  most  destructive  to 
pine  trees.     Nutriment  rich  in  nitrogen  favours  their  growth. 

Parasites  attack  not  only  weakly  plants  but  the  most 
flourishing  individuals.  The  conditions  which  most  favour 
their  spread — damp  air  and  wet  soil — are,  however,  unfavour- 
able to  many  woody  species,  and  external  injuries  of  any  kind 
to  trees  admit  the  spores  of  fungi  to  the  inner  tissues  of  the 
injured  tree  and  thus  favour  fungoidal  attacks.  Wild  plants, 
especially  when  growing  in  masses,  are  just  as  exposed  to  their 
ravages  as  cultivated  plants.  Coniferae  suffer  more  from  fungi 
than  broadleaved  species,  because  the  latter  recover  more 
readily  from  injuries. 

The  question,  whether  a  fungus  is  the  cause  or  conse- 
quence of  a  disease  can  be  solved  only  by  infecting  a  perfectly 
healthy  plant  with  the  spores  of  a  fungus,  and  observing  the 
results.  The  external  circumstances  which  favour  and  hinder 
the  development  of  the  disease  must  also  be  noted.  Such 
observations  are  troublesome  and  difficult,  and  demand  great 
care  and  foresight  to  avoid  deceptive  conclusions.  Much 
information  has,  however,  already  been  obtained,  and  every 
year  is  adding  to  our  knowledge  of  the  subject. 

A  glance  must  be  given  over  the  species  and  modes  of  attack 
and  the  spread  of  a  disease.     In  the  case  of  diseases  which 


428  I'ROTHCTK^N    AfJAINST    PLANTS. 

are  induced  by  certain  conditions  of  soil  and  weather,  the 
whole  of  a  wood  almost  simultaneously  shows  symptoms  of 
disease.  An  attack  by  fungi,  on  the  contrary,  is  propagated  by 
infection  from  one  or  a  few  individuals  which  are  first  attacked, 
and  therefore  starts  from  a  centre,  spreading  generally  in  a 
centrifugal  manner,  like  the  fairy-rings  in  a  meadow  due  to 
Mai'cismiiis  oreadcs. 

5.  Protective  Measures  ariaiust  Funi/i. 

In  order  to  prevent  the  attacks  of  fungi,  good  sylvicultural 
rules  must  be  observed  as  regards  the  regeneration  and 
tending  of  the  crops  of  trees. 

The  most  important  of  these  are :  to  grow  species  suitable 
to  the  locality ;  to  cultivate  the  plants  scientifically,  and  to 
plant  strong  plants  and  in  suitable  mixtures,  especially  of 
broadleaved  trees  with  conifers  ;  early  cleanings ;  timely 
thinnings ;  pruning  from  November  till  January  ;  avoidance 
of  injuries  to  standing  trees  during  fellings;  tarring  wounds. 

To  combat  the  individual  fungi  successfully,  their  life- 
history  must  be  known.     Special  rules  are : 

Isolation  of  attacked  plants  by  trenches  ;  removal  of 
diseased  plants  ;  pruning  attacked  branches  ;  destruction  of 
weeds  that  serve  as  hosts  for  injurious  fungi ;  spraying 
diseased  plants  with  fungicides  *  ;  removal  of  infected 
fallen  needles  or  leaves.  All  infected  material  should  be  at 
once  burned  i)i  situ. 

Section  II. — Fungi  attacking  Conifers. 

The  next  two  sections  give  a  list  of  the  fungi  which  experi- 
ence has  showai  to  be  injurious  to  forest  trees,  with  a  short 
descrii)tion  of  their  external  appearance,  the  classes  of  woods 
and  localities  liable  to  be  infected,  and  the  distribution -areas 
of  the  fungi ;  also  an  account  of  the  damage  done  and  the 
means  for  combating  it.  The  most  injurious  species  are 
marked  with  an  asterisk.  For  a  full  description  of  the 
pathology   of    each    disease   induced   by   fungi,    reference   is 

*  r/".  Lodeniaii,  "  The  Spraying  of  Plants."  Now  York  :  TheMacmillan  Co.  ; 
Loii.l.m,  M;icMnill;ui  .V:  Co..  \wh. 


HONEY    FUNGUS. 


429 


invited  to  the  works  of    1\.  Hartig,*  on  which  these  notes 
are  chiefly  founded. 

It  is  best  for  the  purpose  of  Forest  Protection  to  distinguish 
fungi  attacking  coniferous  trees  from  those  attacking  broad- 
leaved  trees,  and  within  each  group  according  to  the  organ 
attacked  (roots,  stem,  branches,  needles  or  leaves,  or  fruits). 

A.     Root-fungi. 

*1.  Annillarea  mellea,  Vahl. 

a.  Description  and  Mode  of  AttacJc. 

The  honey  fungus,  formerly  named  Agancus  melleus,  L., 

which  is  one  of  the  commonest  in  the  British  Isles,  causes  a 


a  Root  of  a  Scots  pine  killed  by  A. 
mellea,  Vahl.  a  Rliizoniorph,  exter- 
nal to  root,  wliicli  it  liores  at  a. 

Fiff. 


b  Flattened  rliizoniorph  passing  between 
the  dead  wood  and  bast  of    a    Scots 
pine  ;  its  left-hand  branches  are  white, 
and  resemble  ordinary  niycelia. 
207. 


well-known  disease  in  conifers.  The  symptoms  are : — Yellow 
colour  in  the  needles,  which  gradually  dry  up,  and  fall ;  the 
shoots  wilt ;  the  base  of  the  stem  swells  up,  and  the  bark  peels 
off,  whilst  turpentine  exudes  freely,  clogging  together  the  soil 
around  the  tree ;  the  bark  decays,  and  librous  fungoid  tissues 

*  "  The  Diseases  of  Forest  Trees."  R.  Hartif:^.     Translated  by  Somerville  and 
Marshall  Ward.     Macniillau  ic  Co.,  London,  IH'Ji. 


430 


PROTECTION    ACAINST    PLANTS. 


V* 

^ 

«: 

^ 

t 

^" 

1 

? 

5; 

1. 

^ 

? 
^ 

' 

1 

5 

5 

i> 

"5 

<B 

■5- 

fi 

? 

§ 

3- 

f^' 

V 
^ 

1 

a 

a 

2 

-S 

s 

. 

J 

o 

1 

^i 

1 

1 

i 

:>• 

•o 

5 

5; 

5 

Sj 

- 

"v 

^ 

•l" 

o 

.^ 

>-. 

■S 

« 

Si 

1 

1 

^ 

1 

1 

S 

1 

S5 

1 

'< 

^ 

c 

-^ 

^ 

oT 

oT 

a 

a 

, 

rs 

g 

1 

'5 
c 

O 

" 

1 

6 

1 

"5--r! 

•p 

H 

•-S 

1 

o 

1 

^ 

Si 

H 

T3«S 

|| 

oT 

c 

p 

o 

o' 

g 

s 

.2 

1 

it 

3 
o 

A! 
1 

1 

"3 

o 

1^   . 

c 

1 

1 
£ 

i 
s 

j3 

"2 

1 

-2 

li 
i1 

<! 

^" 

CO 

^ 

5 

^ 

1 

% 

5:" 

>s 

■i 

^ 

^ 

1 

7= 

1 
5 

i 

1 

1 
■5 

1 

1 

1 

1 

'5 
i 

1 

g 
.g 
5 

'S, 
If 

|l 

1  s 

1' 

c 

1 

s 

1 

s 

1 

■i 

s 

s 

■| 

1 

5-. 

* 

* 

* 

* 

• 

* 

g' 

-• 

(N 

cc 

-• 

in 

« 

- 

00 

oi 

o 

7 

!N 

TJ 

nT  «-• 

C 

S  o 

"S 

es 

,£3 

1 

<  03 

= 

^ 

II 
111 

Xr/5 

= 

= 

s 

r 

r 

. 

p 

r 

GENERAL   ACCOUNT   OF    FUNGI. 


431 


1  1 

1             i            i 

S     .        .        .    ;        ,        .       J     . 

1            i           i 

1 

1 

1 1 

1  ? 

1 

1 

%       o 

! :  :  :  1  :  : . :  1 
1       1      1   i 

1  ■         s    ■       ll  I 

%                       %                     ^   1       s 
il     I     li     I     i     tl     I 

zn     -j-j         X         ■/.     V,         ct         cc         i-J     02         a; 

■T 

si      s 

.      H 

2     :-' 

1  i 

ii 

1  ^     ^     .:  ■■:     !     !      '  =^     .: 

^  ^     ^     II     1    'M 1     ^ 
1   i     t     ^  5     i     t     J  ?     « 

« J   1   ^  .    .    .   i .?  -r 

5    ^         ?         a    .5        .*        .-        -5     j         « 
5,    .S-:'      Sfcl     I     -^>     -§S     -§a      ^      ?^,•     C 

1   :^-§  :5-§    §,  ^^  ^-g  ^-g    ^   ^r    5 
-^    k^-    l^  ^    ^^    ^;^   \si   \  -^tx    ^ 

s" 

•5 

s   . 

o;        •^" 

la     50          t-"          00      ci          o          -^          c^i     vi          -4 

«5 

i 

d 

i 
§ 

432 


I'ltOTKCTION    ACALVST    FUXCJI. 


appear  in  the  soil,  seldom  deeper  than  four  inches,  that  are 
termed  rhizomorphs.  These  latter  are  persistent  mycelial 
hyphae  like  sclerotic  fibres,  and  resemble  branching  roots ; 
they  sometimes  anastomose.  "White  ribbon-like  hands  of 
mycelium  are  formed  between  the  bast  and  sapwood  and  in 
hollows  in  the  dead  bark  and  bast,  and  often  spread  like  a 
net ;  mycelial  strands  which  pass  into  the  soil  from  these 
white  bands  are  round  and  dark-brown  rhizomorphs,  which 
may  also  develop  between  the  wood  and  the  cortex,  but  are 
then  flat. 


Fig.  208.— EigUt-years-old  Scots  pine  killed  by  A.  mellca,  Vahl.  a  Sterile  rhizo- 
morpliie  straudy.  b  and  c  Fertile  ditto  ;  some  of  the  sporophores  are  abortive. 
(I  Sporophores  spriugiug  from  mycelia  under  the  bark.     {Reduced.) 

Plants  which  have  been  attacked  eventually  die,  and  when 
young  generally  in  the  first  year  of  the  disease.  If  the  dead 
plant  be  examined  microscopically  it  will  be  found  that  the 
bast  and  cambium  have  been  destroyed,  the  resin-ducts  are 
full  of  hyphae  and  enlarged  and  deprived  of  resin  ;  fine  hyphae 
also  proceed  along  medullary  rays  towards  the  centre  of  the 
tree.  Starch  is  transformed  into  turpentine  which  flows  from 
the  tree. 


HONEY  FUNGUS. 


433 


The  edible  sporocarps  first  come  to  light  in  great  numbers 
during  damp  weather  in  October,  at  or  near  the  base  of  the 
dead  trees,  and  spring  from  the  rliizomorphs. 

Fig.  209  represents  a  sporo- 
carp.  Its  cap  varies  in  colour 
from  that  of  honey  to  a 
dirty  brown,  with  dark, 
hairy  scales  ;  its  lamellae  are 
yellowish-white,  and  become 
later  on  speckled  with  reddish- 
brown.  The  cylindrical  stem 
of  the  sporocarp  is  at  first 
dull  red,  and  bears  a  flocky 
white  ring.  The  sporocarps 
emit  myriads  of  white  conidia, 
which  spread  the  infection  to 
other  coniferous  plants  and 
to  dead  broadleaved  species, 
on  which  it  is  saprophytic. 

The  brown  rliizomorphs 
grow  in  all  directions  through 
the  soil,  and  by  means  of 
their  soft  apices  bore  into 
the  roots  of  neighbouring 
plants  and  trees,  which  they 
eventually  kill.  In  dense 
young  growth,  whole  groups 
of  plants  may  be  thus  killed 
and  considerable  blanks  pro- 
duced. In  old  woods,  the 
attack  is  more  confined  to 
individual  trees,  and  the 
disease  spreads  several  feet 
up  their  stems 


Fig.  209. — Fully-grown  sporophore  of 
Armillarea  mellea,  Vahl.  r  Ehizo- 
raorph.     {Xalural  size.') 


h.  Suhjech  of  A  (lack. 

The  fungus  attacks  all  indigenous  or  exotic  conifers,  especi- 
ally the  Scots  and  Weymouth  pines  and  the  spruce ;  the  larch 
not  un frequently  suflfers,  but  the  black  pine  rarely.     Plantsi 

F.P.  F  F 


4..'34  I'ROTKCTIOX    AOAINST    FUNOI. 

may  be  attacked  from  four  to  a  hundred  years  old,  but  especi- 
ally between  four  and  fifteen  years.  In  dense  sowings  and 
multiple  plantings  the  disease  is  at  its  worst,  especially  when 
the  wood  was  originally  stocked  with  broadleaved  trees  on 
which  the  fungus  is  saprophytic,  such  as  beech,  oak,  horn- 
beam, birch,  species  of  Pijrm  and  Primus  *  etc.  The  stumps 
of  broadleaved  trees  left  in  the  ground  of  a  plantation  form 
nurseries  which  propagate  the  fungus.  The  fungus  also 
attacks  timbers  of  bridges  and  other  forest-works. 

Plants  which  are  attacked  generally  die  either  between 
April  and  Jul)',  or  from  the  middle  of  October  to  the  end  of 
November,  and  frequently  the  healthiest  and  most  flourishing 
plants  succumb.  It  is  difficult  to  recognise  plants  which  are 
attacked  until  the  year  before  they  die,  when  their  needles 
turn  pale  and  their  shoots  are  stunted. 

In  older  crops  of  trees,  bark-beetles  frequently  come  with 
the  fungus ;  it  is  not  yet  decided  whether  the  fungus  is  always 
the  primary  cause  of  injuries  in  such  cases. 

In  Russia,  the  fungi  are  collected  for  food,  and  spores  may 
easily  escape  from  the  sacks  in  which  the  fungi  are  trans- 
ported, and  spread  the  disease.  Attacks  of  bark-beetles 
frequently  accompany  the  fungus  in  Russia. 


c.  Profcclive  Rules. 

i.  All  stumps  and  roots  of  broadleaved  trees  should  be 
thoroughly  extracted  before  plantations  of  conifers  are  estab- 
lished on  the  site  of  a  broadleaved  wood,  and  where  the 
disease  has  once  appeared  dense  sowings  of  conifers  and 
multiple  planting  should  be  avoided.  When  the  disease  shows 
itself — 

ii.  All  plants  which  are  attacked  must  be  dug  up  with  all 
their  roots  and  the  rhizomorphs  and  burned.  Should  this 
produce  a  blank,  the  ground  must  be  thoroughly  trenched  and 
all  strands  of  rhizomorphs  extracted  before  it  is  replanted,  and 
then  it  is  best  to  plant  broadleaved  species. 

*  A.  mcllra,  Vahl.,  is  said  b\'  Hartig  to  be  sometimes  parasitic  on  si)ecics  of 
Pninvx.  Mr.  C.  G.  Rogers  reports  that  a  sycamore,  forty  years  old,  was  killed 
by  this  fungus  in  1897,  at  Hartley,  near  riymouth. 


FOMES   ANNOSUS.  435 

iii.  Small  isolation-trenches  should  be  dug  round  plants,  or 
groups  of  plants  which  have  been  attacked,  so  as  to  localise 
the  injury  and  prevent  a  further  spread  of  the  rhizomorphs. 
The  trenches  should  be  far  enough  from  the  attacked  plants 
to  exclude  all  rhizomorphs  from  the  healthy  trees. 

*2.  Fames  annosus,  Fries.  • 

a.  Descriplion  and  Mode  of  A  f tack. 

This  parasite,  formerly  named  Trametes  radicq)erda,U.  Hrtg., 

is   very   destructive    in    pine   and    spruce   forests   of    North 

Germany,  and  is  not  uncommon  in  the  British  Isles ;  it  causes 

root-rot  in  the  Scots  pine,  spruce  and  other  conifers,  and  has 


Fig.  210. — Sporocarp  of  Fomcs  annosus,  Fries.,  on  a  Scots  pine  root.     {Reduced.) 

been  found  on  old  stumps  of  Inrches  and  beech  which  have 
been  injured  by  mice,  although  it  is  probably  not  parasitic  on 
broadleaved  species.  Trees  attacked  by  it  are  eventually 
killed.     Pioot  rot  may,  however,  be  due  to  other  causes. 

The  infection  usually  comes  from  the  diseased  roots  of  a 
neighbouring  tree,  but  also  from  conidia.  The  colourless 
soft  mycelium  is  more  delicate  than  that  of  the  honey 
fungus,  resembling  tissue  paper,  and  is  developed  in  the  bast 
and  wood  of  the  root-system  of  trees.  The  walls  of  the  bast 
and  wood-ceils  are  bored  and  disintegrated  by  numerous 
hyphae  until  the  roots  become  totally  rotten.  The  rot  pro- 
ceeds from  an  infected  root  upwards  into  the  stem  and  from 
the  collar  downwards  into  the  hitherto  sound  roots,  only  in 
the  Scots  pine  does  the  resinous  root-stalk  form  an  impedi- 
ment to  the  ascent  of  the  mycelium.     In  spruce- wood,  the 

F  F  2 


436  PROTKCTION    AGAINST    FUNGI. 

presence  of  this  parasite  is  decidedly  shown  by  the  appearance 
of  black  spots  surrounded  by  white  colour  in  the  spring-wood. 
Outwardly  the  mycelium  penetrates  cracks  in  the  bark,  in  the 
form  of  small  yellowish -white  tufts. 

The  sporocarps  are  chiefly  on  the  root-stalk,  but  also  on 
the  roots,  either  in  the  form  of  incrustations  or  masses  lil<e 
yellow  or  snow-white  grapes.  Under  favourable  circumstances 
of  growth  they  may  assume  the  form  of  brackets. 

The  disease  generally  spreads  rapidly,  turning  the  wood 
first  brown  and  then  white  and  causing  large  hollows  in  it. 
By  the  artificial  infection  of  six  ten-year-old  Scots  pines,  five 
of  them  were  killed  in  a  year  and  a  half.     (R.  Hrtg.)  * 

h.  Subjects  of  Attack. 

The  fungus  has  been  observed  on  the  Scots  and  Weymouth 
pines,  the  spruce,  silver-fir,  of  all  ages  up  to  90  years,  also  on 
juniper  and  on  Scots  pine  transplants  from  five  years  old. 
Finns  rujida,  Mill.,  is  very  susceptible  to  its  attacks.  Its 
spread  is  favoured  by  mice  and  other  animals  which  carry 
the  spores  in  their  fur.  Trees  which  are  attacked  have  pale 
needles  and  stunted  shoots,  as  in  the  case  of  the  honey  fungus. 

c.  Protective  Rides. 

i.  Mixing  broadleaved  trees  with  conifers. 

ii.  Removal  of  all  infected  trees  and  of  all  rhizomorphs,  as 
soon  as  they  are  noticed,  and  filling  up  the  gaps  with  broad- 
leaved  species. 

iii.  Digging  up  and  charring  all  roots  which  show  traces  of 
sporocarps.-  Hess  considers  isolation-trenches  of  little  use  in 
this  case,  as  they  only  favour  the  production  of  conidia  from 
the  exposed  hyphae.  Hartig,  however,  considers  it  possible  to 
scrape  the  walls  of  the  trenches  free  from  conidia,  though  this 
could  probably  be  done  only  in  isolated  cases  of  the  disease. 
Isolation  trenches  will  at  any  rate  prevent  the  infection  of 

•  Mr.  B.T.  Butler,  cryptogamic  botanist  to  the  Government  of  India,  wrote  a 
paper  ("  Indian  Forester,"  Nov.  1903)  showing  that  F.  anmmis,  Fries.,  has  black 
rhizomorphs.  Such  were  also  discovered  by  Dr.  Mayr.  Professor  of  Forestry, 
Munich.     They  penetrate  the  s.jil  to  a  depth  of  20-30  cm.,  one  descending  3  m. 


RHIZINA    INFLATA.  437 

healthy  trees  by  contact  between   their   roots   and  those  of 
diseased  ones. 

3.  lihizina  injliita,  Quelet. 
a.  Desrrijitmi  and  Mode  of  A  Hack. 

This  root  fungus,  also  named  R.  iindidata,  Fr.,  kills  Scots 
pines  of  various  ages.  As  the  nialad5'  spreads  in  a  circle, 
centrifugally  from  the  point  of  infection,  it  is  termed  in 
France  '' Maladie  du  rond"  It  may  be  recognised  by  the 
dying  and  falling  of  tlie  needles  of  affected  trees,  from  the 
month  of  June.  On  digging  up  affected  plants,  the  ground 
around  their  roots  is  found  bound  together  by  numerous 
liyphae,  but  there  is  no  flow  of  resin,  as  in  the  case  of  the 
honey  fungus.  From  the  bark  of  the  pine-roots  protrude 
numerous  white  mycelial  hyphae,  like  Rhizoctonia,*  which  grow 
to  three  or  three  and  a  half  feet  from  the  affected  plants  in  a 
richly  branched,  threadhke  mycelium.  Their  whiteness  is 
due  to  drops  of  etherial  oil,  exuding  from  the  fine  hairs  at  the 
ends  of  the  hyphae.  These  hypliae  spread  in  tlie  soil,  infect 
neighbouring  plants,  and  penetrate  their  wood. 

Massee  states  that  the  fungus  is  saprophytic  on  stumps  and 
on  peat.  It  was  so  destructive  to  Scots  pine,  on  a  loamy  soil,  in 
the  Forest  of  Belleme  (Orne),  in  France,  tiiat  its  cultivation 
had  to  be  abandoned. 

The  sporocarps  resemble  morels,  are  from  1  to  5  cm.  in 
diameter,  and  of  a  dark  chestnut  or  chocolate  colour.  They 
occur  in  the  ground,  connected  with  the  mycelium. 

//.  Siihjerls  of  Allark. 
The  fungus  attacks  plants  of  all  ages,  from  four  years  old. 
In  Belleme,  50  years  old  trees  were  attacked.  Besides  Scots 
pine,  Weymouth  pine,  silver-lir,  larch,  Douglas  fir  and  Sitka 
spruce,  also  sweet  chestnut  have  been  attacked.  It  is  sapro- 
phytic on  old  felling-areas. 

<■.  Protect  ice  Rules. 
Mix    broadleaved    trees    with   conifers.      Choose   conifers 
suitable  for  the  locality.     Isolate  affected  trees  by  trenches. 

•  lihizoctonui  crucoruin,  D.C.,  forms  a  subterranean  web  of  filaments,  termed 
"  copper  web,"  and  attacking  the  crocus. 


438  PROTKCTIOX    AGAINST    FUNf!l. 

B.  Wood  and  Bark  Fungi. 
*4.  Tranu'tes  Piiii,  Fr. 
a.  Dcsciijilmi  and  Mode  of  At  far /r. 
The  mycelium  of  tliis  fungus  develops  in  the  heartwood  of 
the    Scots   pine   and   other   trees   causing   ring-shake.     The 
spring-wood  of  tlie  annual  zones  becomes  gradually  reddish- 
brown,    with    numerous    regularly    distributed    perforations 
coated  with  white,  and  at  length  disappears.     The  remainder 
of  the  wood,  and  especially  the  resinous  autumn-wood,  remains 
intact  for  some  time,  but  eventually  succumbs  so  that  the  tree 


Fig.  211. — a  Sporophore  of  Trametcs  phii,  Fr.,  ou  tlie  smooth  coite.x  of  a 
Scots  pine. 

may  become  completely  hollow.  As  the  mycelium  develops 
most  rapidly  lengthwise  along  the  infected  ring,  we  find  zones 
of  attacked  and  sound  wood  alternating.  The  rotting  wood, 
except  in  the  slightly  resinous  silver-fir  and  in  spruce 
branches,  is  generally  bordered  by  a  zone  rich  in  resin  which 
prevents  the  outward  spread  of  the  mycelium.  The  spores 
gain  admission  to  the  wood  through  fresh  wounds  in  branches, 
where  green  branches  have  been  broken  or  pruned,  and  at 
other  wounds.  The  hj-phae  destroy  the  cell  walls  and  pene- 
trate the  heartwood,  usually  leaving  the  sapwood  unall'ected. 

At  the  scats  of  dead  branches  in  the  case  of  an  infected 
pine  or  larch,  or  anywhere  on  the  bark  of  a  spruce  or  silver- 
tir,  bracket-like  brown  sporocarps  eventually  appear  and  emit 
spores  which  may  germinate  on  fresh  wounds,  unclosed  by 
resin,  on  other  trees. 


FUNGI   CAUSING    RED    OR    WHITE    ROT.  439 

b.  Subjects  of  Attach. 

This  disease  is  commonest  near  villages  and  towns  where 
forests  are  much  exposed  to  mischief,  and  also  in  forests 
liable  to  wind-  or  snow-break. 

Trametes  Pini  is  prevalent  on  trees  from  forty  years  old  and 
upwards,  as  it  does  not  generally  attack  sapwood  owing  to  its 
turpentine,  and  because  wounds  in  young  trees  are  usually 
soon  closed  with  resin.  It  attacks  the  larch,  spruce,  and 
silver-fir,  as  well  as  the  Scots  pine.  In  the  silver-fir,  decay 
spreads  to  the  youngest  woody  zones  which  contain  little 
turpentine. 

The  sporocarps  may  become  very  old,  up  to  sixty  years,  and 
attain  large  dimensions.  The  technical  value  of  the  wood  is 
greatly  impaired  by  the  disease.  The  fungus  is  common  in 
the  Scots  pine  forests  of  North  Germany,  and  in  the  Harz  and 
Thiiringer-Wald  and  South  Germany,  chiefly  on  the  spruce. 
In  the  Carpathians  it  attacks  silver-fir  and  larch  woods.  It 
occurs  in  the  British  Isles. 

c.  Protective  Rules. 

i.  Mix  broadleaved  trees  with  conifers. 

ii.  Pruning  living  branches  of  Scots  pines  which  already 
contain  heartwood  must  be  abandoned.  Living  branches  may 
be  pruned  up  to  thirty  years  of  age,  as  they  contain  no  heart- 
wood,  and  the  infection  is  less  liable  to  occur  in  young  wood. 
In  any  case  prunings  should  be  clean  cut  with  a  saw,  and,  in 
silver-fir,  at  once  tarred  over. 

iii.  All  infected  trees  should  be  removed  during  thinnings. 
In  this  way  the  sporocarps  may  be  destroyed  and  the  spread 
of  spores  hindered  ;  also  wood  of  diseased  trees  may  be  utilised 
before  the  decay  has  gone  too  far,  as  it  is  at  first  frequently 
confined  to  the  upper  part  of  a  tree. 

Wherever  rot  is  due  to  wound-fungi,  it  may  be  avoided 
by  attention  to  the  rules  given  for  Trametes  Pini,  Fr. 

Notes  regarding  Fungi  causing  Red  or  WJdte  Rot. 

A  short  account  will  here  be  given  of  certain  fungi  belonging 
to  the  order  Basidionujcetes,  family,  Pohjporeae,  which  assist 


440  l^ROTteCTION    AGAINST    FaXGl. 

in  causing  red  or  white  rot  in  standing  trees,  the  origin  of 
which  may,  however,  be  due  to  certain  bad  conditions  of 
the  soil  (pp.  673  and  679). 

In  the  case  of  red  rot,  the  substance  of  the  cell-wall  is 
dissolved  by  a  ferment  contained  in  the  protoplasm  of  the 
hyphae  of  the  fungi,  and  a  residual  substance  consisting  of 
gum,  tannin,  mineral  matter,  etc.,  remains,  which,  owing  to 
the  oxidation  of  the  tannin,  assumes  a  reddish-brown  colour. 

Ii(d  Hot  is  caused  by  the  following  fungi : — 

a.  Pohjponis  vaporarius,  Fr. 
On  spruce  and  Scots  pine,  and  rarely  on  silver-fir,  both 
roots  and  wounds  above  ground  being  attacked.  Wood 
attacked  by  this  fungus  becomes  dark-reddish  brown,  and  full 
of  rectangular  cracks,  as  in  the  case  of  Mtndins  lacrimals,  Fr., 
which  causes  dry  rot  in  timber.  When  rubbed  between  the 
fingers,  the  rotting  wood  falls  as  a  yellowish  dust.  Snow- 
white  branching  mycelia,  several  yards  long,  are  formed  ;  the 
sporocarps  form  w  hite  incrustations.  The  spores  gain  entrance 
to  the  trees  through  wounds,  and  the  fungus  is  also  common 
on  beams  in  buildings. 

h.  Poly  poms  Schice'uiilzii,  Hrtz. 

This  is  termed  P.  mollis,  Pers.,  by  Hess,  but  Hartig  has 
now  given  the  correct  name  as  above.  It  is  found  on  Scots 
pine,  and  also  Weymouth  pine  and  larch.  Eesembles  (a),  but 
no  white  brandling  mycelia  occur.  Sporocarps  reddish-l)rown 
brackets. 

r.  J'ohjporns  nulphiirms,  Fr. 

On  the  larch  and  silver-fir  ;  it  is  also  a  very  common  parasite 
on  several  broadleaved  trees,  and  will  be  described  further  on. 

Wliite  Hot  is  produced  when  the  ferment  of  the  hyphae 
decomi^ose  the  lignine  of  the  cell-walls,  leaving  the  white 
cellulose  untouched,  wliich  accounts  for  the  light  colour  of  the 
decomposed  wood.  Some  of  the  causes  of  white  rot  are  the 
following: — 

(d)  PoUjporus  borealis,  Fr.  On  the  spruce  ;  the  wood  turns 
brownish-yellow,  and  characteristic  radial  grooves  appear  in 


PINE -BLISTER.  441 

the  spi'ing-wood  which  are  filled  with  white  mycelia,  the 
latter  having  a  strong  tendency  to  spread  horizontally.  The 
sporocarps  are  annual,  hracket-shaped,  and  frequently  in 
tiers. 

(e)  Poli/poriis  fiilvus,  Scop.  It  produces  white  rot  in  the 
silver-fir,  and  rarely  in  the  spruce.  It  is  frequently  associated 
witli  silver-fir  canker,  descrihed  further  on,  its  spores  entering 
the  wood  hy  the  cracks  in  the  cankerous  swelling.  The  wood 
becomes  yellowish,  and  if  clean-cut,  appears  intersected  by 
numerous  white  longitudinal  bands.  Narrow  dark  lines  appear 
at  the  junction  between  the  sound  and  rotting  wood.  The 
mycelium  is  yellowish,  at  first  growing  strongly,  but  becomes 
later  on  very  fine.  The  bracket-like  sporocarps  are  yellowish- 
brown  above,  ashy-grey  below,  and  almost  smooth.  This 
fungus  is  found  also  on  cherry-trees.* 

*5.  PerUlcriniuni  Piiii,  Wallr.  rar.  corticola. 
(Pine-blister.) 
a.  Description  (mil  Mode  of  All  (tele. 
Scots  pines  infested  with  this  disease,  which  is  very  common 
in  the  British  Isles  and  called  j)//Jt'-?;//.s/er,  are  termed /o,r//  trees 
by  English  foresters  (Fig.  296,  p.  681).    Massee  states  that  it  is 
not  yet  (1903)  known  how  this 
fungus  inoculates  trees,  and 
the  teleutospore  form  of  it 
is  unknown.     It  may  be  a 
form  of  Coleosporiiim  scne- 
cionis,  Fries.,  described  fur- 
ther on,  but  this  is  denied 
by    Cornu    and     Klebahn. 
Hess  described    the  disease,     I'V.^^l^.-Section  of  pine  attacked  by  pin^^ 
'  blister  at  a   for    seventy  years.     (After 

in  1866,  being  probably  the       iiartig.) 
first  to  do  so. 

The  disease  may  be  recognised  by  the  compressed  orange- 
yellow  coloured  little  tufts  of  the  aecidia,  or  sporocarps,  which 
break  through  the  bark  of  branches  and  stems  of  the  Scots 
pine  in  June,  and  eventually  burst  and  set  free  their  spores. 

•    Fur  :i  furtlier  accuimt  of  rod  and  white  rot,  see  pp.  (J73  ft  se/j. 


442 


PROTECTION    AOAIXST    FUNGI. 


The  empty  sporocarps  then  appear  white.  As  a  rule  only 
bark  infected  in  the  previous  year  produces  aecidia.  The 
colourless,  septate  hyphae  of  this  fungus  grow  perennially  in 
the  intercellular  spaces  of  the  bark,  bast  and  medullary 
rays  of  its  host,  sending  short  haustoria  through  the  cell-walls 
to  the  cell-cavities.  The  mycelium  is  developed  chiefly  in  the 
bark  and  bast,  but  penetrates  into 
the  wood  to  a  depth  of  a  hand. 

The  mycelium  converts  the  starch 
in  the  wood-cells  into  turpentine, 
which  becomes  infused  by  drops  in 
the  tissues,  and  cuts  off  the  supply 
of  sap.  Every  year  it  spreads  chiefly 
longitudinally  from  the  diseased  to 
the  sound  wood,  so  that  the  canker, 
wliich  is  covered  with  resin,  con- 
stantly increases  in  size.  The  sap 
being  confined  to  the  sound  portions 
of  the  wood,  produces  abnormally 
large  annual  zones  on  the  side  of  the 
tree  away  from  the  canker  (Fig.  212), 
and  when  the  infection  has  gone 
nearly  round  the  tree,  its  crown  dies 
above  the  point  of  attack,  sometimes 
within  a  year,  but  in  other  cases  a 
long  period  up  to  sixty  or  seventy 
years  may  elapse  before  the  crown 
is  killed. 

Hot  dry  summers  accelerate  the 
death  of  the  crowns  of  infected  trees, 
as  the  wood  surcharged  with  resin 
cannot  pass  on  enough  water  to  supply  the  loss  by  transpira- 
tion. Although  the  summit  of  the  tree  is  dead,  the  lower 
part  of  it  may  continue  to  live,  provided  there  are  enough 
living  branches  below  the  canker  to  nourish  the  tree. 

"Whether  or  not  infection  must  always  proceed  from  a  wound 
in  the  cortex  of  the  tree  is  as  yet  undetermined.  Parts  of 
the  stem  older  than  twenty  to  twenty-five  years  appear 
incapable  of  being  infected. 


Fig.  2\;\.  Firidermiutii  pini, 
Wallr.  (corticola),on  a  .5-year- 
old  shoot  of  !i  mountain  pine. 
The  sporocarps  are  closed 
{a),  or  liave  already  burst  (h). 
(Natural  sizt.) 


PERIDERMIUM   STROBI.  443 

The  spores  of  this  fungus  germinate  on  the  leaves  and  stem 
of  Vinci'toxicinn  officinale.  Much.,  and  on  other  species  of  Vincc- 
toxicum,  producing  the  fungus,  Peridermium  Coniui,  E.  et 
Kleb.  The  teleutospores  from  this  again  infect  pines.  As, 
however,  there  is  no  Vincetoxicum  in  Britain,  where  pine- 
blister  is  very  common,  there  appear  to  be  two  forms  of  the 
disease,  one  P.  Coniui,  R.  et  K.,  and  the  other  P.  Pini,  Wallr., 
the  teleutospore  form  of  which  is  unknown. 

h.  Suhjfds  of  Attack. 

Scots  and  black  pines  of  all  ages  are  attacked  l)y  pine-blister, 
but  preferentially  fifteen  to  twenty  years  old  poles.  It  attacks 
only  organs  two  or  more  years  old,  and  is  commonly  found  at 
verticils  of  branches  and  in  the  crown  of  the  tree.  It  has 
been  often  observed  in  mixed  forests  of  pine  with  beech  or 
hornbeam,  where  the  branches  of  the  broadleaved  species, 
swayed  by  the  wind,  have  rubbed  off  the  bark  of  the  pines. 

The  disease  is  well  known  all  over  Europe  west  of  Poland. 

c.  Protective  Measures. 
Fell  infected  pines  as  soon  as  the  disease  is  noticed.* 

6.  Peridermium  Strohi,  Kleb. 

(Weymouth  Pine-blister.) 

a.  Description  and  Mode  of  Attcu-k. 

The  Weymouth  pine-blister  resembles  the  ordinary  pine- 
blister  externally.  It  attacks  the  cortex  of  stems  and  branches, 
and  especially  at  the  verticils,  causing  long  swellings.  From 
these,  yellow  pustules  eventually  break  out,  which  on  bursting 
emit  spores  in  a  dark  yellow  powder.  The  mycelium  grows 
for  years  in  the  cortex,  and  produces  blisters  (secidia)  every 
year.  The  disease  kills  the  stem  and  branches  above  the  seat 
of  infection,  and  sometimes  the  tree. 

The  disease  is  contracted  by  an  intermediate  host.  This  is 
either  a  currant  or  gooseberry  bush.  Among  the  former, 
Riles  niijrum,  L.,  li.  ruhrum,  L.,  and  R.  aureum,  Pursh.,  are 

*  See  Klebahn,  Dr.  II.,  '•  Furstliche  Bliitter,"  1891,  p.  ir,l.  Id.  Forstlich- 
naturwissciischaftliclie  Zeitsclirift,  iH'jr,  i>.  334. 


444  PROTECTION    AGAINST    FUNGI. 

the  chief  infectors.  The  uredospores  appear  on  the  hwev 
surface  of  the  leaves  of  these  phmts,  at  the  begmiiing  of  June, 
as  small  yellow  cushions.  The  teleutospores  that  arise  from 
them  are  brown  and  in  rows.  The  sporidia  that  come  from 
them  and  germinate  on  the  Weymouth  pine,  cause  swellings, 
in  which  a  mycelium  grows,  and  next  spring,  spermagonia  are 
formed,  and  .necidia  later  on.  Species  of  Rihcs  are  again 
infected,  and  the  disease  becomes  widely  spread.  The  fungus 
on  the  liihes  is  named  Cronartium  ribicolum,  Dietr. 

b.  Suhjeris  of  Attack. 

The  fungus  attacks  young  plants  and  poles  of  Weymouth 
pine,  chiefly  on  their  stems.  It  also  attacks  lateral  branches 
of  older  trees ;  tree-parts  older  than  20-25  years  appear  to 
escape. 

In  1880,  about  30  per  cent,  of  the  Weymouth  pine  in 
Bremen  Town  Park  were  attacked  and  seriously  injured  by 
this  fungus.  The  disease  has  also  appeared  in  other  districts 
in  N.  and  S.  Germany  and  in  Denmark.  It  is  reported  to 
have  originated  on  Cembran  pine  (?)  in  the  Baltic  provinces. 
It  has  not  yet  been  noticed  in  America,  the  home  of  the 
Weymouth  pine. 

c.  Protective  Measiirpft. 

i.  Secure  healthy  plants  of  Weymouth  pine,  when  buying 
from  nurserymen. 

ii.  Remove  and  burn  all  infected  plants. 

iii.  Cut  out  infected  poles  in  thinnings.- 

iv.  Do  not  allow  any  species  of  lUhcs  to  grow  within  at 
least  fifty  yards  of  Weymouth  pine  plantations. 

*7.   M(l<aiiji.snra  pinitorqua,  Rostrup. 

(Pine  Branch-twist.) 

a.  Desrriiition  and  Mode  of  A  ttaclc. 

This  fungus,   formerly  named   Cacoma  innitorquum,  A.  de 

Bary,  is  developed,  especially  in  North  Germany,  in  the  cortex 

of  the  young  shoots  of  the  Scots  pine.      Before  they  have 

attained  their  full  length,  at  the  end  of  May  or  beginning  of 


PINE    BRANCH-TWIST. 


445 


June,  long  yellow  sporocarps  of  the  fungus  appear,  which 
eventually  turn  reddish  yellow,  and  become  raised  like  cushions 
until  the  epidermis  of  the  host  splits  and  so  allows  the  dis- 
semination of  the  spores,  whilst  turpentine  exudes  from  the 
split.     As  the  growth  of  the  pine-shoot  is  checked  at  the  split. 


M' 


tX^ 


Spring  shoots  of  Scots  pine  attiicked  by  Melampsora  pinilorqua,  Eostrup. 
Fig.  214. — Part  of  shoot  in  middle  Fig.  215. — Entire  shoot  (i8)  exuding  resin, 

of  June  with  sporocarps  (a).  The  needles  have  been  pulled  off. 


but  goes  on  normally  elsewhere,  the  infected  part  becomes 
concave,  and  the  healthy  part  bends  over  it.  If  the  attack  is 
slight  the  sickly  place  may  heal  over,  and  the  branches  recover 
their  erect  position.  Often,  however,  splits  follow  one  another 
so  frequently  that  the  shoots  become  twisted  in  various  direc- 
tions.    At  length  it  may  happen  that  the  bark  is  attacked  all 


446 


PROTECTION    AGAINST    FUNGI. 


round  the  shoot,  the  supply  of  water  is  then  cut  off,  the  needles 
turn  yellow,  and  the  shoot  dies  towards  the  end  of  June  or  in 
July,  hanging  down  as  if  it  were  frozen. 

The  plant,  hy  sending  out  several  side-shoots  at  the  base  of 
the  lost  leader,  endeavours  to  replace  it;    but  these  shoots 


Fig.  216.— Part  of  a  two- 
year-old  shoot,  bent  at 
7  owing  to  the  wounds 
caused  by  Melampsora 
pinitorqud,  Rostrup. 


Fig.  217. — Crippled  condition  of  a  Scots  piue  shoot 
wliich  has  been  attacked  by  ^f.  piiiitirrqKd  for 
several  successive  years.    (^Reduced.) 


usually  become  infected  in  succeeding  years.  The  mycelium 
of  the  fungus  grows  in  the  green  cortex  and  becomes  perennial 
in  a  plant  which  is  once  attacked,  while  sporocarps  annually 
appear  in  the  spring-shoots,  except  in  very  dry  springs.  The 
infected  wood  becomes  brown  down  to  its  pith. 


WITCHES- BROOM.  447 

This  fungus  alternates  as  Mclampsora  Trnnnlae,  Tul.,  on 
the  leaves  of  the  aspen,  which  produces  resting-spores  or 
teleatospores ;  these  hihernate  on  the  dead  aspen  leaves,  and 
produce  promyceUa  in  the  spring  from  which  spores  develop, 
which  then  infect  young  pines.  Eostrup  first  discovered,  in 
1883,  that  Caeoma  spores  generated  on  aspen  leaves. 

I>.  Subjects  of  Attack,  and  Distribiitidn. 

This  fungus  attacks  chiefly  young — one  to  ten  years  old- 
Scots  pine,  also  Weymouth  and  mountain  pines,  but  never 
trees  over  30  years  old  ;  it  is  most  frequent  on  damp  soils,  and 
in  cold,  moist,  early  summers.  The  exemption  of  older  pines 
from  the  attacks  of  this  fungus  is  probably  due  to  tRe  fact 
that  the  spores  proceed  from  dead  aspen  leaves  lying  on  the 
ground. 

One  to  three  years  old  cultivations  of  pines  may  be  entirely 
destroyed  by  it,  the  disease  spreading  centrifugally  from  a 
centre  of  infection ;  and  in  older  woods,  especially  after  a 
succession  of  rainy  years,  such  misshapen  stems  may  be  formed 
that  the  marks  of  the  damage  always  remain  patent ;  the 
development  of  the  malady  is  however  retarded  by  dry  weather, 
and  the  disease  disappears  al)out  the  thirteenth  year.  This 
disease  is  known  all  over  Germany,  especially  in  the  north, 
and  did  great  damage  between  1870  and  1873.  For  attacks 
by  M.  Tremulae,  Tub,  on  larch  needles,  vide\}.  469. 

c.  Protpctivc  Measures. 

Careful  choice  should  be  made  of  suitable  localities  for 
growing  Scots  pine. 

Immediate  pruning  and  burning  of  infected  shoots  should 
be  effected. 

Remove  aspen  from  pine  woods. 

Witchcs-hroom. 
Witches-broom  is  an  abnormal  hypertrojih}'  of  twigs  appear- 
ing on  many  broadleaved  and  coniferous  trees,  and  is  caused 
by  the  action  of  animals  as  well  as  of  plants. 


448  PROTECTION   A(;AINST    FUNGI. 

i.  AnioK  OF  Animals. 

Biting  l)y  cattle,  chiefly  goats,  or  l)y  deer,  mice,  mites,  or 
insects.  The  witches-broom  on  lihac,  for  instance,  is  caused 
by  mites  {Phytopus  Loeici,  Nal.) ;  also  on  willows  {Phiitopus 
triradiatus,  Nal.),  etc. 

ii.  Action  of  Plants. 
Parasitic  fungi  cause  witches-broom  on  silver-fir  {McJamp- 
sorclla  Caryophyllacearum,  Schroter),  No.  8.  On  li(jrnbeam 
{Exascus  Carpini,  Rostr.)  ;  Birch  {E.  be tuUn us,  Kostv.) ;  cherry 
(E.  Cerasi,  Fuckl.),  etc.  It  is  not  known  what  causes  witches- 
broom  on  Scots  and  Weymouth  pines,  spruce,  larch,  or  beech. 
Hoffmann,  of  Giessen,  states  that  two  species  of  Cladosporium 
cause  this  hypertrophy  on  Scots  pine,  but  this  is  still  unproved. 
Goeppert  states  that  it  is  due  to  a  local  swelling  of  the 
cambium,  but  does  not  explain  how  this  arises.  These  witches- 
brooms,  as  well  as  those  on  the  Scots  pine,  do  not  appear  to 
be  very  prejudicial  to  their  hosts  :  that  on  silver-fir  is  described 
under  next  heading. 

*8.  MehiwpsorcUa  Caryophyllacearum,  Schroter,  formerly 
named  .Eeidiuni  elatinum.  Link.* 
(Silver-fir  Canker.) 
a.  Description  and  Life-history. 

This  fungus  causes  the  well-known  silver-fir  canker  and 
witches-broom.  The  latter  may  be  distinguished  from  normal 
shoots  of  silver-fir  by  its  erect,  brush-like  growth,  resembling 
the  parasitic  growth  of  mistletoe,  on  the  drooping  branches  of 
the  fir,  and  by  the  small  yellowish-green  needles  growing  all 
round  the  shoot,  which  fall  off  in  their  first  autumn.  There 
is  also  a  slight  swelling  of  tlie  affected  shoot,  and  in  it  the 
mycelium  of  the  fungus  grows  in  the  cortex  and  bast  of  the 
host,  passing  into  the  younger  shoots  and  needles  till  the 
witches-broom,  which  appears  to  live  only  for  sixteen  years,  dies; 
the  mycelium  still  lives  in  the  cortex  of  the  cankerous  swelling, 
but   apparently   not   in    the  wood.      It  does  not  grow  down 

*  •'  Der  Weisstamienkrebs,"  Dr.  Karl  N.  Heck.  Berlin,  Springer,  lSi)4.  Also 
two  papers  by  E.  Fischer  in  Zeitschrift  fur  Pflangenkraukheiten,  Vol.  XI.,  pt.  6, 
I'.toi  and  19(12,  pp.  321—348. 


SILVER-FIR    CANKER.  149 

through  the  cortex  of  an  mfected  branch  into  the  stem,  but  a 
stem-canker  is  produced  when  the  stem  grows  over  the 
infected  base  of  a  branch. 

The  canker  may  be  distinguished  externally  by  a  swelling 
either  on  one  side  of,  or  all  round  the  stem,  on  which  the  bark  is 
deeply  cracked* and  dark  brown,  showing  here  and  there  a  little 
resin  ;  it  crumbles  away  in  parts,  exposing  the  wood.  It  may 
be  found  at  any  height  on  young  or  old  trees  or  their  branches, 
and  may  attain  a  large  size.     The  mycelium  which  grows  in 


Fig.  218. — Shoot  of  Silver-fir  attacked  by  31.  caryophyllaceartint,  Schroter. 

a  Cankerous  swelling,     b  Needles  of  the  witches-broom.     {Natural  size)     After 

Ilartig,  from  Proc.  of  Royal  Soc,  Vol.  47. 

the  cortical  parenchyma  is  the  same  as  that  which  produces  a 
witches-broom,  but  the  latter  is  formed  only  when  the 
mycelium  reaches  a  living  bud.  If,  however,  the  shoots  are 
old  and  have  no  living  buds,  no  abnormal  shoot-production 
takes  place,  and  the  canker  alone  is  formed.  The  infection 
appears  to  spring  from  a  wound  in  the  shoots  affected. 

The  golden  or  orange-coloured  sporocarps  (Spermagonia  and 
Stylospores)  are  formed  on  the  under  surface  of  the  diseased 
leaves.  They  appear  in  two  rows,  open  and  emit  their  spores 
in  June,  the  needles  subsequently  dying.  The  witches-broom 
continues  growing  for  about  16  years,  chiefly  upwards,  and 
branching  freely,  resembles  a  mistletoe  plant  on  the  usually 
horizontal  branches  of  a  silver-fir.     It  at  length  dies,  and  only 

F.P.  G  G 


450 


I'KorKCriON    ACAINST    FlTi\(;l, 


the  canker  remains,  wliich  does  not  produce  any  sporocarps. 
Hess  stated  (1900)  that  no  one  has  yet  succeeded  in  infecting 
a    tree   artificially    b}'   the    spores    of  this  fungus,  and    that 


Fig.  2iy.— Old  witclics-l.rooiii   on  the  Silver-fir.        a  Ciiiikerous  swelling  caiis-ed  l)y  tli^ 
niyceliuni  of  tbe  fungus. 


SILVER- FIR    CANKER. 


451 


a    case    of   polymorphy   may    be   concerned    here,    but    the 

aUernate  host  of   tlie  fungus,  if   one   existed,  was  not  then 

known.     In  1901,  however,  E.  Fischer,  of  Berne,  succeeded  in 

infecting   species   of  Stdlaiia   with   spores   from  a   silver-fir 

witches  -  broom,  and  obtained    Melampsorella   Caryophyllace- 

firiiin,  Schroter,also  nsuned Mdamp- 

sora   Cerastii,   Pers.     This   fungus 

attacks    species    of    Stdhiria    and 

Ccmstium,  common  weeds  in  fiekls 

and  hedgerows  adjoining  silver-lir 

forests. 

The  damage  done  is  direct  and 
indirect,  the  former  consisting  in 
loss  of  increment  and  depreciation 
of  the  quality  of  the  wood,  as 
cankered  wood  cannot  be  used  for 
constructions.  The  indirect  damage 
consists  in  increased  danger  of 
breakage  by  storms  or  snow,  and 
a  greater  disposition  to  insect 
attacks  and  those  of  other  fungi, 
such  as  Polyporus  fidvus,  Scop., 
and  Agaricus  adiposiis,  Fr.,  which 
soon  render  the  wood  very  brittle. 
A  practical  distinction  is  made  be- 
tween sound  and  diseased  cankers  ; 

sound  cankerous  wood  is  30  per  cent,  heavier  than  uncankered 
wood,  it  is  also  harder,  less  fissile,  and  absorbs  only  half  as 
much  water.  Sound  cankerous  trees  yield  some  pieces  of  good 
limber,  but  badly  cankered  trees  are  only  fit  for  fuel. 

Several  cankers  may  be  sometimes  seen  on  the  same  tree, 
and  cankered  trees  may  die  outright  in  hot  summers.  The 
canker  may  live  for  50  years  and  longer.  Mr.  H.  Ingold  has 
calculated,  that,  in  the  Vosges,  21  cankered  trees  are  broken, 
to  one  sound  tree,  and  11  dry  up,  to  one  sound  tree. 


Fig.  220. — Canker  on  a  Silver-fir 
abfjut  4  0  years  old  caused  by  M. 
C'(i)i/ophi/llitct(inini,iit;hT'uteT. 


b.  Suhjeds  of  At  lade  and  Distributiun. 
The  disease  is  everywhere  widespread  in  silver-fir  forests, 
both  mixed  and    pure,    and   especially  in   the  Black  Forest, 

G  G  2 


4-52  PROTECTION    AGAINST    FUNGI. 

where  in  a  mature  crop  of  240  trees  per  acre,  on  the  average 
14 — IG  trees  are  cankered.  It  is  common  in  Windsor  Forest. 
The  fungus  also  attacks  Abies  jncta,  Forh.,  A.  halsamea.  Mill., 
A.  Nonhiiannuina,  Lk.,  A.  cephalonica,  Loud.,  and  A.  Pinsapo, 
Boiss.  Cankerous  stems  are  found  on  every  soil  and  locality, 
hut  the  disease  is  less  prevalent  on  sandy  soils  and  at  high 
altitudes  than  on  loam  or  in  or  near  the  plains,  where  the 
progress  of  the  disease  is  more  rapid. 

The  damage  in  old  woods  is  greater  than  in  young  ones  on 
account  of  the  increase  in  value  of  the  trees,  and  in  pure  high 
forests  than  in  mixed  selection-forests. 
r.  Froteclive  Rules. 

Mix  other  species  not  suhject  to  the  disease  with  the  silver-fir. 

Prune  oft"  the  witches-brooms,  which  chiefly  appear  on  young 
trees,  by  sawing  otT  infected  branches  close  to  the  stem  before 
the  spores  are  dispersed,  and  tarring  the  wounds. 

Kemove  cankerous  stems  in  thinnings  and  preparatory 
fellings,  and  transport  them  speedily  from  the  forest.  Even 
dominating  cankerous  trees  should  be  removed,  and  dominated 
trees  left  to  replace  them.  Those  cankered  all  round  should 
be  first  felled,  as  the  crop  must  not  be  overthinned  from  fear 
of  windfall. 

Old  woods  full  of  cankerous  trees  sliould  he  felled  before  the 
prescribed  period.  The  group-system  practised  in  Baden 
allows  this  to  be  done,  and  it  is  the  most  ell'ective  remedy. 

Weed  away  Stellarias  and  Cerastia  from  the  neighbourhood 
of  silver-fir  woods,  and  do  not  grow  silver-fir  near  the  outer 
boundaries  of  such  woods.  It  is  probable  that  the  disease 
orighiates  otherwise,  besides  from  infection  from  the  weeds 
referred  to. 

*9.  Xectria  Cucurbit tda,  Fr. 

(Spruce  Nectria.) 

II.   Dcsrription  and  mode  of  Attack. 

This  fungus  produces  the  spruce-bark  disease,  and  more 
rarely  attacks  the  Cembran  pine  and  larch.  Its  external 
symptoms  are  : — Pale  colouring  of  the  needles,  the  bark  and 
bast  turning  brown  and  drying  up,  generally  after  insect 
attacks,  and  less  frequently  after  wounds  from  hail  or  other 
causes.    Numerou-.  clusters  of  little  red,  gherkin-like  sporocarps 


SPRUCE    NECTRIA. 


458 


appear  in  the  bark,  which  may  run  into  one  another  like  felt. 
Conidia  issue  from  them  from  late  in  the  autumn  till  the 
spring,  and  infect  surrounding  plants  thi-ough  any  wounds 
they  may  have,  ancl  spread  the  disease. 

The  branching  mj^celium  grows  chiefly  in  the  sieve-tubes  of 
the  soft  bast  and  the  intercellular  spaces 
between  them.  The  growth  of  the  fungus 
is  very  rapid,  but  appears  to  proceed 
chiefly  in  the  season  of  rest  of  the  bark- 
tissues,  not  in  that  of  their  vegetation, 
when  it  is  usually  arrested.  When  the 
fungus  has  spread  all  round  the  stem, 
the  tree  dies,  or  at  least  that  part  of  it 
which  is  above  the  point  of  attack.  If 
however,  the  diseased  tree  can  retain  any 
sound  bark  on  one  side  till  the  ensuing 
spring,  it  is  saved,  for  it  protects  itself 
by  producing  a  corky  sheath  between  the 
sound  and  diseased  part,  which  stops 
the  further  progress  of  the  fungus. 
The  dead  bark  is  then  thrown  off,  and 
the  cankerous  place  grown  over. 

h.  Suhjecls  of  A/fack,  and  Distribution. 

The  fungus  appears  chiefly  on  young 
spruce  from  three  to  thirteen  feet  in 
height,  and  both  in  pure  spruce  woods 
and  in  mixtures  of  spruce  and  beech. 
It  has  also  been  observed  on  Cembran 
pine  and  larch.  It  is  very  common 
in  frosty  localities.  The  conidia  gain 
admission  to  the  tissues  only  through 
external  wounds,  which  are  .  therefore 
extremely  dangerous  in  localities  where 
the  fungus  is  present.  Badly-growing 
l)lants  are  the  more  sul^ject  to  its  attacks, 

as  injuries  by  insect  or  hail  heal  up  less  readily  than  in 
the  case  of  vigorous  plants,  and  are  therefore  longer  exposed 
to  the  attacks  of  the  funf'us. 


Fig.  221 .  —  Spruce 
attacked  by  Xectria 
CHCurbi(u/a,    Fr. 

a  Clrtsters  of  sporocarps 
on  the  dead  bark. 


•151  PROTECTION    AGAINST    FUNGI. 

In  1850,  the  moth  Tortrix  pactolana,  Zell.,  head  ravaged  the 
spruce  forests  of  Bohemia  ;  damage  hy  this  insect  is,  however, 
generally  only  of  a*  temporary  nature,  but  in  this  case,  it  ^Yas 
followed  by  Neetria,  and  great  destruction  of  the  spruce 
occurred.  The  fungus  has  also  appeared  recently  in  the  forests 
of  liavaria  and  Wih-temberg,  but  seems  to  be  absent  from 
North  Germany.  Nisl)et  states  that  it  is  common  in  Britain, 
though  generally  as  a  saprophyte  on  dead  branches  only. 

c.  ProterUve  Rules. 

Cut  down  young  stems  and  shoots  attacked  by  the  fungus 
with  a  pair  of  vine-shears  in  autumn  and  early  winter.  This 
method  does  not  cause  the  spores  to  be  so  scattered  as  wlien 
the  stems  are  felled  with  a  billiiook.  It  costs  about  Ls.  inl.  an 
acre. 

Tbo  larger  stems  attacked  must  be  felled  at  the  same  time. 
In  both  cases  all  the  infected  parts  should  be'  removed  care- 
fully, and  burned  in  an  out-of-the-way  place,  as  the  spores 
easily  spread  from  any  pieces  left  lying  about. 

*10.  iJasyscypha  cali/cina,  Fuckel. 
'  (Larch-blister.) 
a.  Desnipfion  and  mode  of  AHarlc. 
The  nomenclature  of  this  fungus  has  passed  through  several 
stages  :     Willkomm,    in    1867,     described    it    as    Corticium 
Amorpkum,   Fr.,*    which  in  reality  attacks  the  cambium  of 
silver-fir ;  but  in  1868,  H.  Hoffmann  (Giessen)  named  it  Peziza 
rali/riiia,  Rchum.     In  1874,  E.  Hartig  showed  that  the  larch 
fungus  differed  from  P.  calt/cina,  Schum.,  wliich  attacks  silver- 
fir,  spruce  and  pines.     He  therefore  named  it  P.  WiUkoiinnii, 
R.  Hrtg.     This  has  large  aski  and  elliptic  spores,  the  former 
fungus  liaving  oval  spores. 

Masseet  states  that  the  spores  are  globose  and  names  the 
fungus  IhisyHqipha  calycina,  Fuckel,  and  states  that  a  very 

*  Corticium  amoi-phum,  Fr.,  in  the  cambium  of  silver-fir,  may  cause  the  wluilc 
tree  to  dry  up  and  die  without  losing  its  needles.  Large  blanks  have  thus 
been  caused  in  a  forest  near  Nt"udiA(d.  Swilzerland.  '•  Kev.des  E.et  F.,"  Feb.  1 
1  S!»7. 

t    Vitir   iiajicr   in    Transactions    Koyal    Scitlisli    .Arboricullnial    Society   by 

(i.  Massoc,  r.»<i:j. 


LARCH-BLISTER. 


155 


similar  fun<,ais,  D.  irsinaria,  Rehm.,  attacks  chietiy  spruces, 
but  also  larch.  This  latter  fungus  also  attacks  Piniis  excelsa, 
Wall.,  and,  in  America,  is  very  destructive  to  Abies  halsmnra, 
Mill.  Both  species  are  wound-parasites,  but  can  enter  the 
tissues  of  the  living  tree  through  wounds  made  by  a  minute 
parasite,  Kxnsporium,  the  spores  of  which  in  damp  atmo- 
sphere can  germinate 
on  the  cortex  of 
seedlings  or  young 
branches.  The  sporo- 
carps  of  Exosporiuiii 
appear  on  tlie  surface 
of  the  larch  as  minute 
black  dots  and  cause 
cracks  in  the  bark, 
filled  with  resin, 
through  which  iJaai/- 
scypha  spores  can  gain 
admission. 

Dasysciipha  cahj- 
cina,  Fuckel,  causes 
the  destructive  larch- 
blister,  of  which  the 
symi)toms  are  as 
follows  :  —  Appear- 
ance of  little  swellings 
on  the  stem  and 
branches,  chiefly  be- 
low the  crown ;  the 
bark  splits  and  tur- 
pentine exudes,  form- 
ing light  grey-coloured  patches,  and  the  split  increases  till  the 
wood  is  exposed.  Little  3'ellowish-white  sporocarps  of  the  size 
of  a  pin's  head  appear  in  the  cracks.  These  are  incapable  of  at 
once  producing  fertile  spores,  and  merely  wither  away  if 
exposed  to  dry  winds.  Where  they  are  surrounded  by  moist 
air,  however,  they  develop  into  cup- shaped  fructifications, 
whitish  above  and  pale  red  below,  and  these  give  rise  to  fertile 
spores,  which  infect  other  trees.     The  dead  "parts  of  the  tree 


i^.  222. — Portion  of  Larch-stem  attacked  hy.Dfi.tij- 

scypha  cali/ciiia,  Fuckel. 
a  Cracks  with  outflow  of  resin,     h  Sporocarps. 


■1.56  PROTKCTION    AOAINST    FUN(;I. 

turn  l)lack,  and  owing  to  the  swelling  of  the  walls  of  the 
canker  and  the  local  stoppage  of  the  growth,  its  centre 
forms  a  spoon-shaped  depression,  and  the  canker  itself  is 
spindle-shaped.    Several  cankers  may  appear  on  the  same  tree. 

The  fungus  can  gain  admission  only  through  wounds, 
frequently  of  hrachyblasts  eaten  by  Coleophora  lariceUa,  Hl)n. 
(vi(h',  p.  346),  punctures  made  by  Chermes  (pp.  361 — 364),  or 
due  to  snow-break,  etc.  After  the  entrance  and  sprouting  of 
the  spore  the  richly-branching  mycelium  traverses  the  bast, 
but  only  during  the  spring,  as  its  further  progress  is  cut  off  by 
the  formation  of  corky  tissue  separating  the  diseased  place  from 
the  still  healthy  bast.  The  exposed  wood  exudes  turpentine, 
and  in  the  autumn  the  mycelium  grows  again  from  the  cambium 
into  the  healthy  bast  and  increases  the  size  of  the  canker. 
Fresh  layers  of  cork  again  cut  it  ofif,  and  the  growth  of  the 
mycelium  is  repeated,  a  protracted  contest  l)etween  the  tree 
and  the  fungus  usually  ensuing.  In  the  Tyrol,  a  living  larch 
tree  has  been  seen  affected  by  a  canker  100  years  old. 

"When  the  canker  is  small  and  the  growth  of  the  larch 
vigorous,  on  account  of  the  locality  being  suitable  for  it,  the 
damage  done  is  limited  to  the  point  of  attack.  When,  however, 
the  parasite  grows  fast  and  the  growth  of  the  tree  is  noi 
vigorous,  the  mycelium  may  penetrate  the  wood  by  the 
medullary  rays  even  down  to  the  girth,  and  the  flow  of  sap  is 
seriously  interrupted.  The  tree  then  begins  to  languish, 
needles  turn  pale,  twigs  dry  up  and  die,  while  fresh  cankers 
develop,  especially  in  damp  places.  In  such  localities  the 
cankers  may  be  of  reduced  size,  but  the  mycelium  spreads 
throughout  the  wood,  and  the  sporocarps  appear  in  all  directions 
on  the  bark. 

h.  Suhjecis  of  A I  fad',  (nul  Disirihutmi . 

T).  calj/cijia,  Fuckel,  attacks  Larix  europaea,  D.C.,  wherever 
it  grows.  It  occurs  in  Britain,  also,  on  Scots  pine,  mountain 
pine  and  silver-fir.  Japanese  larch,  L.  Lejitolcpis,  Gord.,  has 
also  been  attacked  (Berlin,  1895,  Hennings). 

The  larch-blister  or  canker  is  found  in  localities  wliich  differ 
widely  from  one  anotlier,  but  is  most  prevalent  in  damp  places 
with    moist   air   and    in    frosty    and    cloudy    localities.      The 


LARCH-BLISTER.  457 

disease  spreads  most  rapidly  in  plains  and  valleys  and  among 
low  hills.  Trees  ten  to  twenty  years  old  suffer  most,  but  the 
attack  is  rare  in  the  case  of  tre^s  more  than  forty  years  old. 
Dense  stocking  does  not  suit  the  larch,  and  assists  in  spreading 
the  disease ;  sowings  therefore  suffer  more  than  plantations, 
and  pure  woods  more  than  mixed  woods.  Larches  growing 
with  hroadleaved  trees  are  least  liable  to  canker.  Mr.  Michie, 
in  his  book  on  larch  (Blackwood  &  Sons,  1885),  says,  that 
after  the  first  fifteen  years  tree-parts  are  safe  from  attack. 
Hence,  in  c|  larch  tree,  30  years  old,  and  45  feet  high,  the  tirst 
twenty  feet  or  so  are  safe. 

The  disease  originated  in  the  Alps,  and  when  during  the 
first  twenty  years  of  tbis  century  extensive  larch  plantations 
were  made  all  over  Northern  Europe  theyesca[)ed  the  disease, 
even  when  on  inferior  soils,  l)ut  spores  of  the  fungus  probably 
found  their  way  down  with  larch  seed  from  the  Alps,  and 
the  disease  became  widespread  in  more  recent  plantations. 
In  the  Alps,  it  is  usually  confined  to  individual  trees,  and 
does  not  ruin  wliole  woods  as  in  Germany,  Denmark,  and 
Britain. 

The  reason  is,  that'  in  the  Alps,  there  is  a  sudden  change 
'from  winter  to  quite  warm  weatber,  so  that  the  needles  develop 
rapidly,  whilst  at  lower  elevations  the  soil  becomes  heated  at 
the  end  of  March,  and  the  larch  needles  then  appear,  but  are 
subjected  to  the  treacherous  spring  weather,  and  do  not  harden 
till  the  beginning  of  May.  During  this  prolonged  period  of 
development  of  the  needles  they  are  liable  to  attacks  of  Coleo- 
vhora  laricdla,  Hl)n.,  and  of  Chcrmcs,  which  promote  the 
spread  of  the  canker.  In  the  Alps,  moreover,  the  fertile 
spores  are  only  produced  in  damp  places,  near  the  lakes  for 
instance. 

It  should  also  be  remembered  that,  in  its  native  country, 
larch  has  its  roots  covered  by  deep  snow  till  May,  and  that 
the  soil  contains  plenty  of  moisture  tbroughout  the  year, 
though,  owing  to  the  sloping  ground  on  wbich  the  larch 
grows,  this  moisture  is  never  stagnant.  In  Britain,  tlieii, 
whenever  there  is  not  much  winter  snow,  a  moist  covering  of 
dead  beech  leaves,  or  a  deep  porous  soil  resulting  from  much 
disintegrated  rock,  are  tlie  best  substitutes  for  Alpine  snow. 


458  PROTKCTION    ACAINST    FUNGI. 

The  larch  roots  can  then  spread  freely  and  obtain  plenty  of 
nourishment,  and  the  tree  then  grows  vigorously,  and  either 
escapes  the  disease  or  grows  away  from  it. 

It  is  prohably  everywhere  in  the  British  Isles  damp  enough 
for  the  fertile  spores  to  be  produced,  though  the  disease  is  not 
yet  prevalent  in  Ireland  ;  but  it  is  stated  that  on  good  fertile 
soil  near  the  Scotch  lakes  the  larch  grows  so  rapidly  as  to 
outgrow  the  disease,  even  when  infected. 

Vigorous  larch  trees  are  growing  at  Colesborne,  in 
Gloucestershire,  on  the  banks  of  a  stream  in  a  damp  valley, 
and  the  larch -blister  is  more  fatal  in  the  drier,  flatter  eastern 
parts  of  Britain  than  in  the  moister  hilly  west,  or  in  Ireland. 

The  disease  causes  loss  of  increment,  and  reduces  the 
quality  of  the  timber,  it  encourages  insect  attacks  and  snow 
and  wind  break,  and  ma}'^  kill  trees  outright.  Wherever, 
therefore,  larch  grows  badly  owing  to  unfavourable  soil,  or 
climate,  it  is  better  to  give  up  planting  it. 

c.  Protective  Rules. 

i.  Great  care  should  be  taken  in  the  selection  of  sites  for 
larch  plantations;  pure  larch-woods  should  be  avoided,  except' 
in  early  youth,  and  larch  should  be  given  plenty  of  room.  It 
prefers  northerly  aspects  and  well-drained  but  not  dry  soil, 
slopes  of  hills  and  mountains,  fertile  but  not  too  binding 
soil,  plenty  of  room  for  root-development,  and  abundance  of 
dead  leaves  or  snow  on  the  soil,  so  that  the  ground  may  not 
be  heated  and  the  larch  forced  into  growth  early  in  spring 
and  afterwards' retarded  by  the  spring- frosts.  No  tree  requires 
more  light  or  room  than  the  larch. 

ii.  Larch  grows  best  when  mixed  with  beech,  silver-fir, 
or  spruce,  which  may  be  introduced  after  the  liircli  poles 
have  been  thinned. 

iii.  Great  care  should  be  taken  in  thinnings  to  avoid  wounds, 
especially  in  knocking  off  dead  branches,  which  should  never 
be  done  with  the  sharp  side  of  a  billhook. 

iv.  All  badly  cankei^ed  larches  should  be  cut  out  in  thinnings. 
Plantations  ruined  by  the  disease  sliould  be  felled  and  replanted 
witli  another  species. 


PINE-SHOOT    FUNGUS.  459 

11.  Cenaiu/iuvi  Abictis,  Duby. 

(Pine-shoot  -Fangus.) 
a.  Description  and  Mode  of  AilarJc. 

This  fungus  causes  the  death  of  isolated  shoots  of  young 
pines.  As  a  rule,  only  yearling  shoots  are  attacked,  but  some- 
times 2  to  3  years  old  shoots  also,  chiefly  at  their  tips.  The 
shoots  die  from  April  till  June,  from  the  top  downwards. 
Mycelia  are  found  in  the  dead  shoots,  including  their  buds. 
The  cells  of  the  cortex  turn  brown  and  become  filled 
with  resin,  the  tissues  are  rent.  The  inner  tissues  down. to 
the  giith  also  turn  brown.  The  mycelium  is  most  abundant 
in  the  Imds.  The  needles  die  from  the  base,  contrary  to  those 
attacked  in  the  pine  needle-cast  (p.  465).  They  turn  yellowish 
green,  yellowish  brown,  and  eventually  brown. 

This  is  not  a  wound-parasite.  The  sporocarps  are  dark 
brown  roundish  cushions,  breaking  out  from  the  mid-nerves 
of  the  needles  or  from  the  base  of  yearling  shoots,  but  cliiefly 
from  those  2 — 5  j'ears  old  dead  shoots.  The  spores  germinate 
only  after  the  dead  shoots  have  fallen  to  the  ground,  where 
they  obtain  sufficient  moisture. 

If  the  number  of  infected  shoots  is  sufficiently  numerous, 
the  trees  attacked  may  die,  otherwise  the  damage  consists  in 
loss  of  increment  only. 

/'.  Subjects  of  Attack,  and  Distribution. 

This  fungus  specially  attacks  Scots  pine,  of  any  age,  but 
chiefly  12 — 20  years  old  thickets  and  polewoods.  Also  black 
and  Weymouth  pines.  Until  1883,  it  was  considered  as 
saprophytic  only  on  dead  spruce  and  silver-fir  branches. 
Then  F.  von  Thiimen  suggested  that  it  is  parasitic  on  Scots 
pine.  This  was  proved  to  be  the  case  in  1892  by  Frank.,  the 
fungi  having  appeared  in  184  Prussian  forest  districts.  The 
exceptional  nature  of  the  weather  in  1892  certainly  assisted 
in  its  spread.  The  fungus  occurs  in  France  and  Sweden,  as 
well  as  in  Germany.  ^ 

Ilartig  considers  that  the  damage  done  in  1892  was  due 
to  the  intense  insolation   in   February  and   March,  while  the 


tBO    •  PROIF/'TIOX    AfJAIN.ST    FUXOI. 

roots  of  the  pines    were   in    frozen  ground,    and    could    not 
tlM'icfor.'  siii>j.ly  the  water  lost  by  insolation. 

r.  rrolrrlive   Ihihs. 
lieiuove  atYected  poles  in  the  thinnings. ' 

12.  Pcstalozzia  Hartufu,  Tubf. 

Tliis  fungus  causes  a  disease  in  spruce  and  silver-fir  seed- 
beds and  nursery-lines.  Its  first  symptoms  are  that  a  number 
of  plants  turn  pale  and  die,  and  when  pulled-up  it  will  be 
noticed  that  their  cortex  close  to  the  ground  is  withered, 
whilst  above  this  withered  portion  the  stem  has  attained  its 
usual  dimensions.  The  mycelium  of  the  fungus  may  be  found 
in  the  bark,  where  the  contraction  in  the  stem  takes  place, 
and  sporocarps  spring  from  the  point  of  attack. 

This  disease  appears  to  attack  several  broadleaved  species 
as  well  as  conifers,  and  all  infected  plants  should  be  at  once 
pulled-up  and  burned.  For  instance,  in  a  beech-nursery  at 
Vicdessos,  Ardeche,  altitude  1,350  m.,  the  plants  were  lined 
out  at  two  years  old,  and  by  August  became  chloritic  and  dried 
up.     Those  remaining  in  the  seed-beds  were  not  attacked.* 

Pull  up  and  burn  all  affected  plants. 

13.  Scptona  j)arasitica,  R.  Hrtg. 
(Spruce-shoot  Fungus.) 

This  fungus  causes  the  wilting  and  death  of  young  spruce 
shoots,  especially  lateral  shoots.  The  needles  of  the  attacked 
plants  become  brown  and  M'ilt,  as  if  they  had  been 
attacked  by  late  frost,  and  generally  break  off.  In  the  course 
of  the  summer  globose  black  i)ycnidia  api)ear  at  t\\%  base  of 
the  shoots,  from  which  threadlike  conidiaphores  arise.  These 
appearing  in  white  rows,  spread  the  disease  in  May  on  the 
fresh  opening  shoots.     Sitka  spruce  is  also  attacked. 

This  disease  has  been  observed  chiefly  in  yo«ng  spruce,  in 
nurseries  and  plantations.  It  also  attacks  the  leading  shoots 
of  poles,  and  sometimes  causes  groups  of  plants  to  die, 
as  in  Ehrenfreidersdorf,  in  Saxony.  It  is  common  in  the 
llertogenwald,  near  ^)a,  in  the  Ardennes. 

Cut  off  and  burn  diseased  branches. 

♦   Hciir.v  :   "  Kev.  des  ?}.  et  F./'  1<»01,  p.  '>M. 


DOUGLAS-FIR    BLIGHT. 


461 


14.  Botritis  Douylassii,  Tubf. 

This  fungus,  termed  Douglas  -  lir  blight,  and  known 
for  several  years  as  attacking  2 — 6  years  old  Douglas  firs, 
in  1895,  was  found^on  young  Scots  pine  in  Holland  (Ritzema 
Boos).  "Well in g ton ia  seedlings  have  also  been  attacked  at 
Kew. 

The  needles,  especially  the  upper  ones,  wilt,  and  the 
whole  plant's  growth  is  weakened.  A  brownish  grey  mycelium 
appears  on  the  upper  shoots,"  which  become  curved  and  die, 
the  needles  falling  off.  Conidia  form  on  the  fallen  needles 
and  minute  black  sclerotia  on  the  dead  branches.  The  latter 
produce  conidia  if  the  air  be '  moist.  Young  plants  are 
frequently  killed.  Nisbet  states  that  this  fungus  is  identical 
with  Sclerotinia 
J'uckeliana,  De  Bary 
{B.  cinerea),  the  vine 
pest.  This,  how- 
ever, appears  to  be 
doubtful. 

Spray  with  Bor- 
deaux mixture  and 
burn  aft'ected  plants. 

C.  Needle-fungi. 

1 5 .  Peridermium  Pin  i 

acicola,  E.  Hrtg. 

(Pine  Needle-rust.) 

During  April  and 
May,  on  the  one-year 
or  two-years  needles 
of  young  pines  of 
different  species, 
orange  -  yellow  blis- 
ters appear,  about  the  size  of  a  mustard  seed,  often  several  of 
them  being  in  a  row  on  one  or  both  ides  of  the  needles.  When 
ripe,  they  turn  brown  and  split,  emitting  their  spores,  and 
leaving  on  the  needles  blackish  spots  with  lighter  bordtrs. 
The  mycelium  is  perennial  on  the  needles,  and  witliout  killing 


223. — Peiid^mium  Pini  acicola,  E.  Hrtg.,  on 
Scots  pine  needles,     a  Burst  sporocarps. 


462  I'KOTKCIIOX    ACAINST    Fl  N(il, 

them,  may,  during,'  tlie  ensuin*;  year,  develop  fresh  aecidia. 
The  needles  die  and  fall  only  when  the  disease  is  very  intense. 
The  pine  needle-rust,  as  the  disease  is  termed  by  Massee, 
comes  from  spores  of  s^jecies  of  Coleospoiiuni  seuccionis,  Fr.,  a 
fungus  infesting  several  species  of  Scnecio,  chiefl}'  biennials, 
(S*.  vuhiaris,  L.,  *S'.  riscosus,  L.,  S.  vernalis,  W.  et  K, 

The  fungus  prefers  plants  3  to  10  years  old,  but  may  attack 
trees  up  to.  30  years ;  it  is  widespread  throughout  Europe, 
including  the  British  Isles,  but  does  little  harm  to  the  trees  it 
attacks.    Weed  out  groundsell  from  pine  woods  that  it  attacks. 

1(3.  Ai'cidiiun  Ahretinum,  Alb.  et  Sclnv. 
This  fungus  causes  a  needle-rust,  which  appears  at  mid- 
summer on  the  previous  year's  shoots  of  the  spruce,  the 
needles  then  assume  a  dull  reddish-yellow  colour  ;  during 
August,  bright-red  aecidia  of  the  size  of  a  pin's  head  project 
from  the  needles,  and  at  the  end  of  August  or  the  beginning 
of  September  they  burst  and  emit  their  yellow  spores 
in  a  cloud  of  dust.  The  affected  needles,  which  on  lateral 
shoots  are  usually  only  on  the  upper  side  of  the  branches,  die 
and  fall  Ijefore  the  close  of  the  year,  and  the  fungus  may  be 
thus  distinguished  from  ClirysoDujxa  Abietis,  Ung.  The 
alternate  hosts  of  the  fungus  are  several  species  of  rhodo- 
dendron in  the  Alps,  and  Ledum  jxdustrc,  L.,  in  Finland  and 
parts  of  North  Germany,  and  these  plants  carry  the  disease 
through  the  winter.  Spruce  trees  of  all  ages  are  affected, 
especially  in  the  Alps,  from  an  altitude  of  1,000  metres  to  the 
highest  limit  of  spruce,  where  whole  spruce-woods  sometimes 
assume  the  yellowish-red  colour.  The  disease  is  also  very 
prevalent  in  liussia  ;  no  practical  remedy  has  been  devised 
against  it. 

17.  Aecidium  columnaye,  Alb.  et  Schw. 
(Silver-la-  Needle-rust.) 
Aecidia  break  out  in  July  and  August  on  both  sides  of  the 
mid-rib  of  silver-fir  needles,  in  the  shape  of  long  yellow 
blisters  full  of  spores.  This  fungus  alternates  as  Melampsora 
Goeppertiana,  Kiilm,  on  the  cowberry  {Vacciiiium  Vitis- 
Idaca,   L.),    and   causes   that   plant   to    become    al^normally 


SPRUCE  NEEDLE- RUST.  468 

tall,   with   a   thickened    spongy  stem,   at   first  whitish,  then 
rosy-red,  and  eventually  dark  brown. 

The  fungus  kills  silver-fir  needles  and  causes  them  to  fall, 
but  it  is  not  widely  spread  and  becomes  dangerous  only  when 
young  thickets  of  silver-fir  spring  up  among  cowberry  plants, 
when  the  latter  should  be  uprooted  and  destroyed. 


''ig.  224. — Spruce  twig  attacked  by  Chrysomyxa  ylhietis,  Ung.,  in  autumn. 
{Natural  size.) 


18.  Ckrijsomyxa  Ahietis,  Ung, 

(Spruce  Needle-rust.) 
a.  Description  and  Life-history. 
This  form  of  spruce  needle-rust  may  be  recognised  by  dull 
yellow  bands  appearing  from  May  to  the  middle  of  June  on 
yearling  spruce  needles. 

They  gradually  become  broader  and  assume  a  brighter 
yellow  colour.  Towards  the  end  of  August  brownish  longi- 
tudinal   stripes   appear   on    the   aflected    needles,    which    by 


4fi4- 


PI{()TK(T1()N    ACAIN'sr    FUNGI. 


November    assume    a    goklon-j-ellow   colour,    and    swell    up 

slightly  on   one   or   both    sides  of  the  mid-rib ;    the  fungus 

hibernates   on    the   tree    in    this    condition.      The   swelling 

becomes  greater  at  the  beginning  of  spring,  and  from  April 

to  the  middle  of   Maj^  the  epidermis   of   the   needle   bursts 

and  the  spores   are   scattered,  the  affected  needles,  parts  of 

which  are  still  green,  wilting  and  falling  in  June  and  July. 

The    spores   which    are    disseminated    in    May,    when    the 

young   shoots   of   the   spruce   are   forming,   can   then  infect 

them    and    continue 

J,  ^  ,/  the  disease. 

a  b  €  a 

h.  Siihjcds  of  Attarlr, 
and  Distribution. 
The  fungus  attacks 
only  yearling  needles, 
usually  those  on  the 
lower  branches,  and 
rarely  near  the  top  of 
the  tree. 

Spruce  is  most  sub- 
ject to  this  disease 
when  from  10  to  40 
years  old.  In  damp, 
dense,  10  to  20  years 
old  thickets,  the  fun- 
gus is  most  common, 
but  the  nature  of  the 
soil  does  not  appear  to  have  any  influence  on  it.  It  is  met 
with  up  to  altitudes  of  5,000  feet,  and  is  most  frequent  on 
south  and  south-west  aspects,  or  in  valleys  exposed  to  the 
south,  whilst  damp  weather  favours  its  spread,  wherever  spruce 
is  extensively  grown. 

The  damage  done  consists  chiefly  in  loss  of  increment,  and 
exposure  to  attacks  by  bark-beetles,  but  the  trees  are  not 
often  directly  killed  by  it.  Spruce  trees  are  not  usually 
sufficiently  advanced  in  growth  to  become  infected  when  the 
spores  ripen,  and  thus  frequently  escape. 

The  disease  occurs  in  Germany  Denmark,  and  Sweden. 


Fig.  22;'). — Spruce  needles  attacked  by  ChrysoKiyxa 
Ahidis,  Uug.     (Somewhat  enlarged.) 

a  Sc  b  Finst  appearance  of  disease  in  the  form  of 

pale-yellowish  marks  on  needles. 
c  Needle  with  reddish-brown   longitudinal   blisters 

(end  of  March  and  beginning  of  April). 
d  Needle  with  fully  formed  orangejellow  cushion 

(May). 


PINE    NEEDLE-CAST. 


465 


c.  Proteclive  Rules. 

i.  Careful  choice  of  suitable  localities  for  spruce. 

ii.  Carry  out  early  and  strong  thinnings,  especially  on 
trees  affected  by  the  disease,  and  promi)tly  remove  the  latter 
from  the  forest. 


*19.  Lophodennium   Pinastri,  Sclirad. 

(Pine  Needle-cast.) 

a.   D/>scn'/)tioH  and  Lifc-histnrij. 

On  the  primordial  needles  of  young  Scots  pines,  solitary 
brown  spots  may  appear  in  July  or 
later  on  in  the  year,  and  if  the  affected 
needles  are  examined  microscopically, 
the  mycelium  of  Lophodcrminni  (Hys- 
teriiim)  Pinastri,  Schrad.,  will  be  found 
in  them.  Black  spermagonia  subse- 
quently appear  before  winter,  but  their 
spores  do  not  germinate,  as  ascocarps  do 
not  develop  till  the  second  year  after 
infection.  As  a  rule  the  diseased  pri- 
mordial needles  die  in  the  spring,  with- 
out falhng  from  the  plants,  and  older 
needles  frequently  turn  completely  brown 
in  March  and  April  and  fall  off,  owing 
to  the  formation  of  cork  at  their  base. 
This  sudden  shedding  of  pine  needles  is 
the  characteristic  of  the  disease  so  widely 
spread  in  Germany  and  termed  Schiitte, 
or  needle-cast,  which  may,  however,  be 
due  to  other  causes  besides  the  fungus, 
as  explained  on  p.  685.  If,  owing  to  a 
mild,  wet  winter  and  spring,  the  black 
sporocarps  should  burst,  which  only 
happens  when  they  are  exposed  to  much  moisture,  the  spores 
issue  from  them  and  infect  fresh  plants.  This,  however, 
frequently  happens  only  after  the  needles  have  fallen.  Dry 
summers  and  cold  winters  therefore  impede  the  spread  of  the 
fungus,  which   is  frequently  only  saprophytic  on  old,  dying 

F.P.  H  H 


Fig.  226.— (a)  Yearling 
Scots  pine  needles 
attacked  by  Pine 
needle -cast,  the  base 
green.  (/y)  Dead  two 
years  old  needles.  Ripe 
apothecia  (x)  and  empty 
jytjcnidia  (y),  in  April. 
After  Hartig. 


166  PROTECTION    AGAINST    FUNGI. 

pine  needles,  in  crowded  seed-heds.  This  saprophytic  form 
of  the  disease  was  ahvays  present  in  the  Scots  pine  nursery 
at  Coopers  Hill  College,  but  never  injured  the  pine  seed- 
lings or  transplants.  The  latter  were  kept  two  years  in  seed- 
beds and  two  years  in  nursery-lines,  and  about  50,000  healthy 
four  years  old  plants  were  removed  from  the  nursery  every 
year  from  1891  to  1900. 

h.  Suhjerfs  of  Aitarlc,  cmd  Di.^lrihutioii. 

Needle-cast  attacks  Scots  pine  wherever  it  is  grown  ;  also 
black  and  maritime  pines  are  attacked. 

As  a  rule,  the  fungus  attacks  only  1  to  .5  years  old  plants,  but 
it  has  been  observed  on  poles  up  to  twenty  years  old.  Damp 
cloudy  localities  are  favourable  to  its  spread,  and  plains 
and  lowlands  suffer  more  than  mountains  and  hills.  Large 
regeneration-areas  and  dense  stocking  also  favour  its  spread. 
Under  certain  unfavourable  conditions  of  soil  and  climate,  the 
cultivation  of  Scots  pine  must  be  abandoned,  owing  to  this 
disease,  and  the  area  stocked  with  Weymouth  pine,*  or  some 
other  resisting  species. 

r.  Frohrlirc  Measures. 

i.  Spray  2  to  3  years  old  plants,  in  July,  with  Bordeaux 
mixture,  50  gallons  water,  6  lbs.  CaS04,  4  lbs.  unslaked  lime, 
6  lbs.  soft  soap.  A  French  nurseryman  thus  treated  Scots 
pine  seedlings ;  in  the  following  February,  not  a  single  plant 
sprayed  showed  a  sign  of  disease,  while  80  to  100  per  cent,  of 
those  unsprayed  were  dead. 

ii.  Mix  spruce  or  Weymouth  pine  with  Scots  pine,  in 
lines  or  belts  running  from  north  to  south,  so  as  to  interfere 
with  the  dissemination  of  the  spores  by  damp  westerly  winds. 

iii.  In  nurseries,  the  seed  should  not  be  sown  thickly  in 
drills,  and  the  yearlings  should  be  transplanted  into  nursery- 
lines,  or  at  once  into  the  forest.  New  Scots  pine  nurseries 
should  be  made  in  localities  free  from  the  disease,  best  among 
broadleaved  trees,  in  any  case  not  near  pine-woods,  which  are 

•  Accordinf,'  to  Hartig,  the  Weymouth  pine  in  Germany  and  Denmark  suflEers 
fioni  a  similar  fundus.  IJiipodrrmn  hrtjchi/spori/m,  llostr.,  and  the  larch  from 
Lophodermium  htririniim,  Duby,  which  however  may  be  only  a  saj)rophyte. 
Rostrup  states  that  black  pine  is  attacked  by  L.  ffi/rinii,  which  kills  its  needles. 


LOPHODERMIUM    MACROSPORUM. 


1.67 


especially  dangerous  to  the  west  of  the  nursery.     The  spaces 
in  nursery-beds  between  the  rows  of  seedings  should  never  be 
covered  with  pine  branches,  which  favour  the  spread  of  the 
disease,  but  with  leaves  of  broad  leaved  trees  or  moss. 
iv.  Burn  carefully  all  affected  plants. 

20.  Ij.  niacrosporuni,  R.  Hrtg. 
a.   Dcsrriptmi  and  mode  of  Alhick. 


Fig.  227. — a  Umler  surface  of  a  spruce  twi;,'-  in  winter,  attacked  by  Lophodermium 
macrosporitm,  R.  Hrtg. 
a  Dead  brown  needles  at  the  base  of  the  second  year's  shoot. 
J3  Freshly  attacked  third  year's  needles. 
7  Xecdlcs  witli  black  perithecia. 
/;  Hrown  TU'cdlcs  witli  ripe  perithecia  (3)  not  yet  burst. 


This  fungus  on  the  spruce,  according  to  E.  Hartig,  causes 
either  needle-rust  or  needle-cast. 

The  former  disease  appears  in  mountainous  regions  at  mid- 
summer as  a  rusty  discoloration  of  needles  on  two  years  old 
shoots,  and  in  the  plains  later  during  autumn  ;  finally  l>lack- 
sporocarps  {PcriOicria)  appear  on  the  under  surface  of  the 
infected  needles,  which  burst  longitudinally  and  emit  their 
spores  in  the  succeeding  April  or  May.  The  needles  with  the 
empty  sporocarps  remain  on  the  tree  for  several  years.  At 
first  only  the  needles  on  two  years  fild  and  older  shoots  are 
attacked ;  later  on,  those  of  yearling  shoots  as  well.     Tbis  is 

H  H  2 


•16S  l»R(lTK("riON    AGAINST    FUNOI. 

due  to  tlie  fungus  requiring  from  six  months  to  three  years  to 
develop  its  sporocarps.  At  first,  the  needles  are  more  resis- 
tant, but  when  the  tree  becomes  weakened,  they  are  more 
easily  killed. 

In  the  case  of  needle-cast  a  more  virulent  form  of  the 
disease  occurs,  and  the  needles  turn  red  in  August,  then 
brown,  and  fall  before  the  winter. 

The  spores  of  all  species  of  Lophoderminm  gain  admission 
through  the  stomata,  and  the  wetter  the  weather,  the  sooner 
the  spores  ripen. 

h.  Subjects  of  Al lark,  (nul  [)islributi<ni. 

The  disease  affects  chiefly  pure  crops  of  15  to  30  years  old 
spruce,  especially  in  the  lower  part  of  their  crowns,  but  is 
unimportant  except  when  needle-cast  takes  place.  Dense 
crops  are  most  affected  ;  mixtures  of  spruce  with  other  species 
suffer  less.  The  mineral  nature  of  the  soil  and  the  altitude 
apiiear  to  have  no  influence,  but  in  Saxonj',  the  disease  is 
worst  on  fertile,  moist  soil  and  on  S.  and  W.  aspects,  where 
the  spores  ripen,  at  the  time  of  the  prevailing  winds.  When 
badly  attacked,  the  trees  die,  in  the  third  year  of  an  attack. 

c.  Protective  Measures. 

i.  Avoid  pure  crops  of  spruce,  wherever  the  disease  is 
common. 

ii.  Cut  out  and  burn  affected  subjects. 

iii.  Eemove  the  soil-covering  of  dead  needles  near  affected 
trees,  and  do  not  use  this  litter  in  spruce  woods. 

21.   Lophodcnuinm  uerviscqnium,  D.  C. 

This  is  a  very  similar  fungus  to  that  described  above,  and 
affects  the  previous  year's  and  older  needles  of  silver-fir, 
turning  them  brown  and  eventually  causing  them  to  fall  from 
May  to  July.  Numerous  dark  brown  pustules  may  be  noticed 
on  the  upper  surface  of  infected  needles,  and  long  dark-brown 
sporocarps  eventually  break  out  in  the  mid-rib  of  their  lower 
surface.     The  spores  ai^  only  half  the  size  of  those  of  No.  20. 

They  ripen  in  April  of  the  succeeding  year,  on  the  needles 


LARCH    NEEDLE-CAST. 


469 


in  their  third  year,  or  on  older  needles,  but  a  large  number  of 
the  infected  needles  have  generally  fallen  before  this  occurs. 

This  disease  is  widespread   in  silver-fir  forests,  and   has 
proved  destructive  in  the 
Erzgebirge,     where     the 
trees  lose   most   of    their 
needles. 

Burn  affected   subjects. 


22.      Sphaerdla     Liricina, 
n.  sp. 

(Larch  Needle-cast.) 

a.   Desrriji/ion   and  mode  of 

Alfac/c. 

Often  in  July,  smaller  or 
larger  brown  specks  appear 
on  larch  needles,  on  which 
later  very  small  black 
conidiophores  project  in 
groups.  From  beneath 
these,  the  colourless  my- 
celium,   which    is    richly 

ramified,  develops  in  the  needles,  partly  in  their  intercellular 
spaces,  partly  in  the  cells  of  their  parenchyma. 

Inside  the  conidiophores,  small  hollows  develop  with  very 
fine  basidia,  at  the  ends  of  which  are  very  small  coiiidia. 
These  fall  off"  and  are  carried  away  by  wind,  or  washed  out 
by  rain,  and  reach  the  young  twigs  of  the  tree,  where,  after 
a  few  hours,  they  germinate  and  infect  the  needles.  The 
needle-cast  thus  increases  progressively  in  intensity.  By  the 
death  of  the  twigs,  the  longitudinal  growth  of  the  affected 
plants  suffers,  and  owing  to  crowding  by  neighbouring  trees, 
they  often  die.  The  fall  of  sickly  or  dead  needles  commences 
in  July. 

On  the  needles  that  fall  to  the  ground  in  the  following 
summer,  globose,  dark  brown  perithecia  develop,  which 
spread  the  disease.  The  mycelium  growing  in  the  needles 
becomes   hard,  thick    walled,   and   is   coloured    light    brown. 


Fig.  228.— Twig   of    Silver-(ir   attacked   by 

L.  ucrviscqicium. 

a  Unaffected  needles. 

h  AttackHd  needles  tiiriiiug  brown. 

(■    Needles  with  ripe  sporopluires. 


170  PROTECTION    AGAINST    FUNGI. 

The  club-like  asci  in  the  perithecia  contain  eight  1-celled  and 
later  2-celled  spores.  The  perithecia  ripen  at  the  end  of  May 
and  the  beginning  of  June.  In  three  weeks  from  the  moment 
of  infection,  they  produce  fresh  conidiophores. 

//.  Suhjccis  of  Atlaclc,  and  Dislrilndion. 

The  fungus  appears  to  attack  larch  of  all  ages.  Dry, 
breezy  localities  are  less  liable  to  the  disease  than  damp  foggy 
ones.  For  this  reason,  larches  on  mountains,  where  the 
summer  air  is  dry,  whenever  the  air  is  -cloudless,  are  less 
endangered  than  those  on  hills  and  in  lowlands.  The  season 
during  which  the  fungus  can  form  conidia  is  much  shorter 
in  mountains  than  in  lowlands. 

The  danger  is  greatest  in  pure  larch  woods  and  in  mixed 
woods  of  larch  and  spruce.  In  the  former,  the  infection  is 
easy,  owing  to  the  propinquity  of  the  larch  trees ;  in  the 
latter,  the  fallen  infected  larch  needles  lie  in  masses  on 
the  spruce  branches,  where  the  ascophores  can  easily  infect 
the  larch.  A  mixture  of  beech  and  larch  is  favourable,  as  the 
dense  fallen  beech  leaves  hinder  the  spores  from  ascending. 

Japanese  larch  is  also  attacked. 

In  the  cold,  wet  summer  of  1894,  this  disease  was  so 
prevalent  in  Upper  Bavaria,  that  by  the  beginning  of  August 
most  of  the  larch  needles  had  fallen. 

c.    i'rolerlirc   Mmsi/rcs. 

i.    Grow  larch  in  suitable  localities. 

ii.  Mix  larch  with  beech  and  not  with  spruce. 

Melampsora  Treinulae,  Tul.,  also  named  Caeoma  laricis,  Hrtg., , 
p.  4-17  (Fig.  '288,  ]).  480),  also  induces  larch  needle-past.  Aspen 
should  not,  therefore,  be  grown  in  larch  woods. 

23.   TricJiospJiaci  ia  ])arasiti<a,  II.  Hrtg. 

a.  Desrrijition  and  mode  of  Alhal:. 

Tlie  fine   colourless  mycelium  of   this  fungus   covers    the 

twigs  of  the  silver-fir  down  to  the  buds,  especially  on  their 

under  surface,  and  spreads  to   the  lower  needles,  whilst  the 

shorter  u[)per  needles  usually  escape  infection.     The  mycelium 


TRICHOSPHAERIA    PARASITICA. 


47; 


forms  superficial  white  -cushions  on  the  white  hues  of  stomata 
of  the  needles.  They  therefore  become  discoloured,  and  at 
length  quite  brown  ;  they  do  not,  however,  fall  from  the  tree, 
but  hang  down,  being  still  attached  to  the  twig  by  the  mycelia 
of  the  fungus. 

In  November,  on  the  brown  cushions  appear  small  globose 
tomentose  perithecia,  con- 
taining greyish  spores,  which 
easily  germinate  when  they 
fall  on  twigs  of  silver-fir,  and 
the  disease  is  thus  spread. 
The  mycelium  hibernates  on 
the  twigs  and  needles  and 
grows  again  on  to  the  new 
spring-shoots,  attacking  the 
needles  from  the  base  up- 
wards, so  that  needles  on  the 
older  shoots  which  escaped 
during  the  previous  year 
may   now   be   attacked. 

Trees  once  attacked  by  this 
fungus  appear  never  to  be- 
come free  from  it,  from 
which  its  dangerous  nature 
is  evident. 


b.  Subjects  of  Attack,  ami 
Distributwn. 


Fig.  229.— Twig  of  Silver-fir  attacked  by 
Trichosphaeria  parasitica,  R.  Ilrtg. 

a  Sound  needles. 

h  Dead  brown  needle.s  fixed  to  the  twig 
by  mycelial  strands. 

c  Under  surface  of  needles  with  white 
mycelia  and  dark  sporocarps. 


This  disease  is  widespread 
in  silver-fir  forests  and  espe- 
cially among  20  to  40  years  old  woods  on  the  lower  branches 
and  on  advance-growth,  and  according  to  von  Tubeuf,  it  also 
attacks  the  spruce,  but  is  rarer  than  on  silver-fir.  It  has 
done  much  damage  in  the  Bavarian  forests,  near  Passau  and 
other  places.  It  has  been  noticed  that  lower  branches  of 
silver-fir  attacked  by  Trichosphaeria  parasitica,  K.  Hrtg., 
escape  attacks  by  Corticium  amorphum,  Fr.  (p.  454),  when 
neighbouring  silver-fir  are  attacked  by  tlie  latter  fungus. 


172  I'KOriXTION    ACAINsr    FUNfJI. 

c.  Prolciiivf  Measuirs. 
Underwood,  and  diseased  l)ranclies  and  twigs,  should  be 
removed   by   cleaving,   pruning   and   cutting   off  twigs    with 
shears. 

24.  llcrpotrkhia  iwira,  11.  Hrtg. 

(Spruce  Black  Needle-rust.) 

a.  Desrription  and  mode  of  A  ffarjc. 

The  grey  mycelium  of  Herjwtrichia  nigra,  R.  Hrtg.,  forms 

an  irregular,  dark  coat  on  twigs  and  needles  of  the  spruce, 

the  mountain  pine,  and  the  juniper,  up  to  about  a  meter  from 

the  ground. 

/'.  Subjects  of  A  (lack,  and  Distribution. 

Tliis  fungus  occurs  in  the  Bavarian  Alps  only  in  mountains 

where   snow    lies   long,    and    there   is   very    deadly,   natural 

regeneration  being  sometimes  entirely  prevented  ;    it  is  less 

hurtful  at  lower  altitudes.     It  covers  the  young  plants,  in 

seed-beds,  under  the  snow,  to  such  an  extent  that  in  spring 

they  cannot  remain  upright.     It  also  does  much  damage  to 

mountain  pine.     Juniper  is  also  attacked. 

c.  Protective  Measures. 
i.  No  nurseries  f*liould  be  made  where  snow  lies  deep  in 
mountains. 

ii.  Plant  close  to  the  stumps  of  felled  trees. 

D.  Fungi  attacking  Cones. 

25.  Aecidiinn  strohiliuinn,  Alb.  et  Schw. 

(Spruce-cone  Fungus.) 

Tiiis  fungus  develops  its  mycelium  in  the  still  green  scales 

of  spruce-cones  and  destroys  them.    The  hemispherical  brown 

aecidia  are  crowded  together  on  the  inner  surface  of  these 

scales. 

The  infected  cones  which  have  fallen  to  the  ground  may  be 
easily  detected  by  their  opened-out  appearance.  Spores  enter 
the  young  cones  early  in  spring.  The  teleutospores  are  not 
yet  known.     The  disease  occurs  wherever  spruce  is  grown. 

Another  fungus,  Aecidium  Conor  am  Piccae,  Bss.,  also  affects 
spruce-cones,  and  may  be  distinguished   from   the  above  by 


FUNf4I    ATTACKING    CONES. 


473 


there  being  at  least  two  aecidia  on  each  scale  of  the  affected 
cones.  After  the  aecidia  burst  and  disjDerse  their  spores,  pale 
spots  are  left  on  the  scales. 


Fig.  230. — Spruce  cone  attacked 
by  Aeciditim  strohilinum,  Rss. 


Fig.  231. — Sporophores  of  A. 
strohilinum,  Alb.  et  Schw.,  on 
the  under  surface  of  a  scale  of 
a  spruce  cone. 


Section  III. — Fungi  attacking  Broadleaved  Trees. 

The  numbers  of  dangerous  fungi  attacking  broadleaved 
trees  may  be  limited  for  description  hare,  to  eight,  besides 
some  wound-parasites.  The  most  destructive  are  marked 
with  an  asterisk,  as  in  the  list  given  on  the  next  page. 


A.  Root-fungi. 

*1.  llosellinia  qnercina,  E.  Hrtg. 

a.  De.scripliofi  and  Lifp-hislonj. 

The  leaves  of  infected  1  to  3  years  old  oak  seedlings  become 

gradually  pale  and  at  length  dry  up.     This  commences  with 

the  topmost  leaves  and  proceeds  downwards.     At  the  top  of 

the  taproot  just  below  the  surface  of  the  ground,  the  bark 

and  wood  turn    brown  and  shrivel  up,   and    this   at   length 

spreads  to  the  whole  taproot  and  the  plant  dies.     On  pulling 

up  the  plant  and  examining  its  tap-root,   black    spheroidal 

sclerotia  of  the  size  of  a  pin's  head  are  seen,  which  spring 

from   numerous   brown    rhizomorphs,  which    have  branciied 

freely  and  surround  the  plant's  roots,  and  are  prolonged  into 


1-71 


IMIOTKCTION    AGAINST    FUNGI. 


the  soil.    These  rhizomorphs  readily  communicate  the  disease 
to  roots  of  iieighhoiiring  plants,  as  in  the  case  of  the  lioney 

fUHilUS. 


Organ  attacked. 

No. 

Name  of  fungus. 

Species  attacked. 

Natural  order. 

Family. 

A.  Koot-systeni 

1. 

*ItoselUnia  quer- 
cina,  R.  Hrtg. 

Oak  .     .   •.     ; 

Pyremmy- 
celes. 

Meluiiomeue. 

B.  Stem     and 
blanches  (in 
the  wo.k1  or 
bark). 

2, 

Poli/ponig     aul- 
p'knreu.i,  Fr. 

Oak  and  birch 

Jiaif  idiom  y- 
cctex. 

Polyporcite. 

3. 

'Xeiirla       d'ltix- 
siina,  Tul. 

Beech, oak  and 

other  l)road- 
leaved  trees. 

Axcoiiiycetvii 

Spliaeriaceae 

4. 

\.  ci'nnaharlna, 
Fr. 

Ma[)le,     lime, 
horse  chest- 
nut, elm. 

5. 

Aglauspora     titl- 
eula,  Tul. 

Oak  .... 

" 

" 

C.  Cotyledons 
anil  leaves. 

6. 

*  Ph  i/tophthoru 
fugi,  R.  Hrtg. 

Beech,  maple, 
ash,  robinia, 
and  conifers, 
esp.   spruce, 
S.  pine. 

Phy  corny- 
ceten. 

Pcrom- 
sporeae. 

s. 

lifii/tisma  acry't- 
nil  III,  Fr. 

Mrliiiiipsara  Hiir- 
tigli,  Thum. 

Maples  .     .     . 
Willows     .     . 

Axcoiityreteii 
Urediiieff;    . 

Ilyteriareae. 

Mi-laiiijisor- 
aceae. 

The  method  of  infection  is  very  interesting  ;  as  the  tap-root, 
except  at  its  lower  extremity,  is  protected  by  cork,  the  shoots 
of  the  mycelium  attack  the  side  roots.  At  the  places  where 
these  branch  off  from  the  main  roots,  little  fleshy  swellings 
are  formed,  which  send  out  conical  processes  through  the  cork 
into  the  inner  tissues  of  the  tap-root.  The  fungus  grows  only 
in  damp  warm  weather,  and  if  the  weather  be  dry,  the  infected 
plant  can  delay  the  progress  of  the  fungus,  by  cutting  it  oflf  by 
cork-formation  from  the  still  healthy  tissue^s.  By  means  of 
the  sclerotia,  the  fungii.s  can   i)ersi.st  thiough  dry  periods,  or 


POLYPORUS    SULPHUREUS.  475 

hibernate,  which  the  ordinary  mycehum  cannot  do.  The 
disease  is  also  perpetuated  by  conidia  springing  from  the 
portions  of  the  mycehum  growing  above  ground,  or  by  spores 
produced  either  from  the  sub-aerial  portion  of  tlie  oak-plant 
or  in  the  ground,. these  as  a  rule  only  germinate  in  the  year 
following  that  of  the  original  infection. 

h.  Suhji'cis  of  Aftac/c,  and  Dislri/mlioii. 

This  fungus  is  very  dangerous  in  seed-beds -and  dense  sow- 
ings in  the  open  up  to  2,600  ft.  altitude,  especially  in  wet 
years.  It  is  common  in  Nortli-West  Germany,  also  in  Wiirt- 
temberg,  where,  in  1890,  it  killed  100,000  1—3  years  old 
seedlings. 

r.  Prokiiive  Rules. 

i.  Places  where  the  fungus  has  appeared  should  be  isolated, 
by  digging  trenches  one  foot  deep  to  prevent  the  spread  of  the 
rhizomorphs. 

ii.  Plants  which  have  been  attacked  must  be  at  once 
removed-  and  burned,  which  can  always  be  done  in  nurseries. 

B.  Stem  and  Branch  Fungi. 
2.  Poli/ponis  .siil2)}itiirus,  Fr. 

This  widely-distributed  fungus,  which  is  very  common  in 
the  British  Isles,  q^nd  has  been  already  referred  to  as  attacking 
the  larch  and  silver-fir,  destroys  the  wood  of  oaks,  sweet 
chestnut,  poplars,  tree- willows,  alders,  birch,  etc.,  and  fruit- 
trees. 

The  infection  occurs  at  wounds  in  the  branches  of  trees  ; 
the  wood,  in  consequence,  turns  reddish-brown,  cracked  and 
dry,  the  niycelium  spreading  through  the  cracks  and  forming 
large  felted  white  sheets,  it  also  fills  the  vessels,  which  on  the 
different  sections  of  the  wood  a4}pear  like  white  lines  or 
points.  At  the  scars  of  dead  branches,  or  other  parts  of  the 
stem,  large  sulphur-yellow,  fairly  smooth,  fleshy  sporocarps 
appear  annually  which  are  somewhat  reddish  above  and  very 
conspicuous. 

All  infected  trees  should  be  felled  if  this  does  not  open  out 


i76  PROTKCTION    AOAINST    FUNGI. 

the  wood  too  much,  and  great  care  should  be  taken  durinf^ 
fellings  to  avoid  wounds.  Broken  or  forked  branches,  which 
it  is  advisable  to  remove,  should  be  sawn  off  cleanly  and  the 
section  tarred. 

Other   Wound-Parasites  attaching   Oak  and  other  Broadleaved 
Trees. 
All  such  fungi  gain  admission  through  wounds  and  broken 
branches,  so  that  they  can  be  avoided  by  good  silviculture. 

a.  Pohjjionis  dri/adeus,  Fr. 

White  and  yellow  irregularly  shaped  longitudinal  marks 
appear  in  the  wood,  which  at  length  becomes  cinnamon- 
coloured  and  rotten.  Tlie  sporocarps  are  large,  brown  and 
hoof-shai^ed,  but  do'not  last  long. 

b.  Pohjporus  igniarius,  Fr. 

The  commonest  cause  of  white  rot.  Infected  wood  becomes 
pale  yellow  and  gradually  lighter  in  colour  and  softer.  The 
tannin  is  at  once  attacked  and  decomposed  by  young  mycelia 
of  this  fungus,  so  that  oak-wood  loses  its  characteristic  odour, 
the  absence  of  which  is  an  excellent  practical  test  of  incipient 
unsoundness.  This  fungus  also  occurs  on  fruit-trees  and 
other  broadleaved  trees.     Sporocarps,  hoof-shaped. 

P.  hetuUnus,  Bull,  and  J*.  laevUjatus,  Fr.,  cause  red  and 
white  rot  respectively  in  birch,  the  former  having  roundish 
sporocarps,  and  the  latter,  incrustations. 

c.  Hi/diium  du'trsidciis,  Fr. 

Also  causes  white  rot  in  oak  and  beech.  The  wood,  and 
especially  its  spring  zones,  turns  ashy-grey,  at  first  in  stripes. 
The  sporocarps  are  yellowish-white  incrustations  or  brackets. 

d.   Thelt'phora  iierdix,  R.  llrtu-. 
Produces  the  waW-known partrldrie-icood  form  of  rotten- wood 
{liebhiihnholz),  which  is  common  in  Germany,  but  not  known 
as  British  by  Marshall  Ward.    Tlie  dark  reddish-brown  rotten- 
wood  becomes  honeycombed  with  whitish  blotches  surrounded 


BEECH-CANKER.  477 

by  hard  walls.  Later  on,  these  blotches  become  greyish-yellow, 
and  are  filled  with  mycelium.  The  sporocarps,  brownish-yellow 
incrustations. 

e.  Stercum  hirsufum,  Fr. 
Snow-white  or  yellow  longitudinal  bands  surrounded  by 
brown  tissue  appear  in  the  wood,  which  is  said  to  be  yellow- 
or  ichite -piped.  Sometimes  the  whole  of  the  wood  turns 
uniformly  yellow.  The  sporocarps,  at  first  mere  incrusta- 
tions, later  on  assume  prominent  brown  horizontal  edges. 
Common  in  Britain. 


*3.  Ncctria  ditissima,  Tul. 

(Beech-canker.) 

a.  JJpsrrij)/ion  and  mode  of 'A  I /ark. 

Beech-canker,  which  may  be  recognised  by  the  local 
destruction  of  the  cortex,  resembles  silver-fir  and  larch 
canker.  It  may  be  produced  on  the  beech,  either  by  Nectria 
ditissima,  Tul.,  or  by  insects  {Lachmis  exsiccator,  Alb.,-  Coccus 
fagi,  Barensp.,  p.  366),  or  by  frost.  The  disease  is  sometimes 
occasioned  by  several  of  these  agents. 

The  attacks  of  the  fungus  may  be  diagnosed  by  the  local 
destruction  of  the  cortex,  and  the  appearance  of  small  white 
tufts  of  conidiophores ;  and  later  on  by  dark-red,  spherical 
sporocarps  on  the  canker.  The  infection  always  arises  at  a 
wound  caused  by  abrasures  of  bark  by  felled  trees,  hail,  etc., 
and  from  the  point  of  infection  the  fungus  spreads  more  or 
less  regularly  in  the  wood,  but  most  quickly  along  the  stem. 
The  wood  turns  brown  and  dies  wherever  it  is  attacked.  The 
diseased  portion  of  the  wood  appears  sunk  into  the  stem, 
owing  to  the  hypertrophy  of  the  growth  of  the  portions  of  the 
stem  round  the  canker. 

Thus  the  attacked  branches  and  stems  15ecome  spindle- 
shaped.  The  canker  becomes  every  year  deeper  and  more 
open. 

//.  Subjects  of  Attack,  and  Distribution, 

The  beech-canker  chiefly  attacks  the  beech,  but  oaks,  ash, 
hornbeam,  hazel,  alder,  lime,  cherry,  maple,  and  especially 


t7H 


I'nOTHC'lION    AOAINST    KUNfil. 


apple,  are  also  attacked.  It  is  found  in  thickets  5  to  7 
years  old,  hut  also  in  100  years  old  woods,  and  is  worst 
anionfjfst  healthy  smooth-harked  trees. 

Infected  hranches  eventually  die,  and  infected  trees  in  the 


I' I'-'.  'S4'l.  Nertria  dili 
Tul.,  on  a  heech.  a  Com- 
mencement of  [jjic  <lisea.sp, 
wliich  lias  proceeded  deeper 
into  tlie  wood  nt  h. 


Fig.  233. — Canker  on  an  oak  niused  l)y 
Xectria  ditissima,  'liil. 


course  of  time  assume  extraordinary  shapes,  and  are  fit  only 
for  firewood. 

TIk;  disease  has  heen  known  since  1805  in   the  Saxon  Erz 
mounlains  iind  in  the  extensive  beech  forests  in  Hesse.     It  is 


CORAL- SPOT    DISEASE.  479 

common  in  the  British  Isles,  especially  on  apple  trees.  It  is 
frequently  associated  with  the  attacks  of  the  insects  mentioned 
above,  which  expose  the  cambium  zone  to  the  admission  of 
spores,  by  the  wounds  they  make  in  the  bark. 

c.  Protective  Rules. 

Cut  out  all  infected  trees  in  cleanings  and  thinnings,  pro- 
vided too  large  gaps  are  not  thus  caused  in  the  standing-crop. 

Avoid  all  injuries  to  the  bark  during  felling  operations. 

Afi'ected  branches  in  orchards  should  be  pruned  down  to 
the  sound  wood  (October  till' March),  and  the  exposed  sections 
covered  with  coal-tar. 

Burn  all  cankered  wood. 

4.  Nectria  cinnaharina,  Fr. 

(Coral-spot  Disease.) 

a.  Description  and  mode  of  Attack. 

The  presence  of  this  parasite  in  living  broadleaved  trees 
may  be  diagnosed  by  the  breaking  out  of  the  vermilion- 
coloured  sporocarps,  which  eventually  turn  brown  and  finally 
white,  on  the  stem  or  branches  of  the  tree,  chiefly  in  the 
autumn,  after  rainy.weather.  Healthy  shoots  suddenly  dry 
up  and  die,  the  wood  turning  green  or  black.  The  infection 
takes  place  at  a  wound  of  some  kind,  chiefly  of  branches,  but 
also  of.  roots.  The  mycelium  grows  rapidly  in  the  wood, 
pierces  the  walls  of  the  wood-fibres,  decomposes  the  starch, 
and  leaves  a  green  substance  within  the  infected  tissues.  The 
cambium  and  bark  remain  sound,  but  by  the  destruction  of 
the  wood,  the  water-supply  is  cut  off  from  the  crown,  tli'e 
leaves  witlier  and  drop  off,  and  the  shoots  dry  up.  The  sporo- 
carps appear  in  autumn  or  spring  on  the  dead  l)ark  of  the 
infected  trees,  and  the  danger  of  infection  is  then  greatest. 
Severe  frost  or  sun-blister  may  produce  wounds,"  through 
which  the  spores  gain  admission  to  the  wood. 

b.  Subjects  of  Attack,  anil  iJis/ritnituni. 

This  fungus  is  saprophytic  on  the  dead  branches  of  various 
broadleaved  trees  and  shrubs,  such  as  uiaples,  cherries,  robinia, 


480 


l'IU)TK(TI()N    A(;AIN.ST    FUNGI. 


dogwood,  l)lackthorn,  birch,  etc.  Marshall  Ward  notes  that 
it  may  be  often  seen  on  pea-  or  bean-sticks,  which  become 
dotted  with  red  points. 

As  a  parasite,  it  attacks  3'oung  plants  of  maple,  lime,  horse- 
chestnut,  elm,  and  mulijerry,  and  soon  kills  them.  It  is  very 
widespread  throughout  Europe. 


Kij:.  234. — Maple  stem  showing  the 
vermilion  coloured  sporocarps  («)  of 
Nectria  citimil/iirina,  Fr. 


i>,'.  235. — Section  of  Maple  stem 
attacked  by  Kectria  chuiaharinu,  Fr. 
Between  a  and  h  the  wood  is  coloured 
bright  green  owing  to  the  decomposi- 
tion of  the  tissues. 


r.    Prolpclire  Rules. 

i.  Clean  pruning'  of  broken  branches  and  tarring  the 
wounds. 

ii.  All  twigs,  branches,  or  stems  which  show  sporocarps  of 
tlie   fungus  should   be  cut  oil"  and  burned. 


OAK    BARK-]}LISTER.  181 

5.  Af/laospora  taleola,  Tul. 

(Oak  Bcirk-l)lister.) 

The  bark  of  oaks  that  still  possess  a  smooth  cortex, 
becomes  brown  in  patches,  either  on  one  side  only,  or  all 
round,  and  the  affected  part  dies.  The  dead  bark  may  be 
either  in  little  patches  surrounded  by  living  bark,  or  may 
extend  to  a  yard  and  more  along  the  stem.  The  diseased 
places  vary  in  breadth,  being  pointed  at  their  upper  and  lower 
extremities.  The  m3^celium  grows  in  the  cortex,  and  pene- 
trates also  into  the  sapwood,  which  may  become  brown  and 
die ;  the  heartwood  is  not  affected. 

Between  the  diseased  and  healthy  tissues,  a  broad  zone  of 
cork  develops,  which  excludes  water  from  the  inner  tissues. 
The  border  of  the  diseased  cortex  therefore  dries  up  and 
produces  no  sporocarps.  Between  this  dry  border  zone  and 
the  rapidly  decaying  bark,  cracks  occur.  The  cortex  under 
the  cork,  which  persists  for  a  few  years,  decays  and  is  finally 
thrown  off.  The  cankered  spot  thus  produced  quickly  forms 
a  callus  and  heals  up. 

In  the  second  year  of  the  disease,  round  or  oval  sporocarps 
appear  in  the  cortical  parenchyma,  under  the  cork.  In  the 
midst  of  them,  one  or  two  (rarely  three)  little  prominences 
pierce  the  cork  zone  and  exhibit  openings  of  one  or  several 
perithecia  surrounded  by  white  powdery  conidia.  The  sporo- 
carps in  the  cortex  consist  of  dark  brown  pseudo-parenchy- 
matous  mycelia.  The  bottle-shaped  perithecia,  containing 
ascospores,  protrude  from  this  mycelium.  As  a  rule,  several 
of  these  ascospores  coalesce. 

It  is  not  yet  decided  whether  or  not  this  infection  does  any 
injury  to  the  affected  parts. 

Pestalozzia  Hartigii,  'i^uhi.  (p.  4()0),  attacks  young  broad- 
leaved  plants  in  nurseries  and  on  natural  regeneration  areas. 
It  is  commonest  on  2 — 5  years  old  beech,  maple  and  ash, 
which  it  eventually  kills.  The  disease  runs  the  same  course 
as  that  already  described  for  conifers.  It  was  very  prevalent 
in  different  parts  of  Germany  during  the  wet  summers  of 
1888,  1892. 

F.P,  I  I 


482  I'KOTFJTIOX    AGAINST    FUNdl. 

C.  Seedling  and  Leaf  Fungi. 

•  «;.   I'hiilopltOiora  FcKji,  Pi.  Hrtji. 
(Beech-seedling  Mildew.) 

a.  DparriptidU  and  mode  of  Aitaclc. 
This  very  destructive  fungus,  calso  named  7-^.  omnivora, 
De  Barv,  causes  great  damage  among  beech  seedlings  ;  these, 
when  affected,  turn  black  and  die  from  below  upwards,  during 
their  germination  or  immediately  after  the  cotyledons  have 
appeared.  The  little  stem  shrivels  up  and  turns  brown  above 
and  below  the  cotyledons,  whilst  they  are  still  green,  or  dark 
specks  appear  on  the  cotyledons  or  on  tlie  young  leaves. 
Within  six  or  eight  days  after  the  first  appearance  of  the 
disease,  it  attacks  the  whole  plant,  especially  in  protracted 
rainy  weather  in  the  months  of  May  and  June.  In  dry 
weather  the  attacked  plants  appear  as  if  singed  by  fire.  It  is 
frequently  accompanied  by  Lachnus  fagi,  L.,  a  species  of  aphis. 
The  first  infection  of  the  beech  by  the  parasite  comes  from 
oospores  that  have  remained  in  the  ground  since  former 
sowings.  The  mycelium,  Avhich  is  intercellular,  spreads  into 
fhe  stem  and  cotyledons,  and  numerous  hyphffi  break  through 
the  epidermis  or  stomata,  and  produce  lemon-shaped  spor- 
angia. After  the  bursting  of  these,  fresh  sporangia  are  formed, 
and  the  spores  are  spread  in  all  directions,  and  in  this  way 
tiie  disease  may  extend  over  a  considerable  area  of  young 
plants  by  attacking  their  cotyledons,  or  primordial  leaves. 
The  development  of  the  fungus  is  so  r.ipid  that  in  rainy 
weather  and  in  damp  localities,  in  3  or  4  days  after  the  first 
appearance  of  the  disease,  sporangia  are  formed  on  the  host. 
At  the  same  time,  thick-walled  oospores  are  produced  sexually 
within  the  cotyledons ;  these  fall  to  the  ground  in  the  rotting 
tissues,  and  may  then  remain  alive  for  four  years  and  more. 
These  oospores  reproduce  the  malady  from  year  to  year  if  the 
place  be  used  again  for  sowing  beech.  In  dense  sowings  on 
damp  soil,  the  fungus  infects  the  roots  of  the  plants  until 
whole  rows  of  them  die  at  once. 

Beech  natural  reproduction  in  shady  woods,  beech  seed- 
beds and  nursery  lines,  as  well  as  those  of  other  species, 
suffer  greatly  from  this  fungus. 


SYCAMORK    LEAF-BLOTCH.  483 

h.  Subjprfs  of  Attack,  and  Distribution. 

The  fungus  lias  been  observed  to  attack  beech,  maple,  ash, 
and  robinia,  at  the  seedling  stage,  and  several  conifers,  especi- 
ally the  spruce  and  Scots  pine.  Hence  the  name  "  omnivora.'" 
The  symptoms  are  similar  in  these  other  cases.  If  only  the 
leaves  of  the  seedling  are  affected,  it  may  recover,  but  when- 
ever the  stem  is  attacked  from  below,  it  succumbs.  Worms 
drag  down  infected  seedlings  into  their  holes,  and  hence  gaps 
sometimes  arise  in  what  was  formerly  a  flourishing  nursery- 
bed. 

This  fungus  causes  considerable  damage  to  all  the  species  it 
attacks,  and  the  spores  are  transported  by  wind,  mice,  roe- 
deer,  and  by  the  tread  of  men  or  horses,  or  even  cart  wheels. 
Damp,  warm  years  are  favourable  to  the  spread  of  the  fungus. 
It  has  been  noticed  all  over  Germany. 

r.  Protective  Rules. 

i.  Use  Bordeaux  mixture,  as  already  descril)ed  (p.  466). 

ii.  Pull  up  all  infected  plants  and  collect  leaves  lying  on 
the  ground  as  soon  as  the  disease  is  noticed,  and  burn  them. 

Seed-beds  should  be  carefully  watched  in  May  and  June  for 
this  malady.  The  workman  should  wear  an  apron,  in  which 
he  places  the  infected  plants,  and  should  take  care  not  to 
tread  on  the  beds  and  bury  any  oospores.  Any  bed  which  has 
been  attacked  should  be  examined  daily. 

iii.  The  soil  in  nurseries  may  be  thoroughly  burned,  by 
digging  trenches  30cm.  deep  and  30cm.  apart,  and  filling  them 
with  dry  brushwood  and  burning  this.  Keep  the  lire  going 
for  two  days. 

iv.  Beech  and  coniferous  seed-beds,  where  the  disease  has 
appeared,  should  for  several  years  be  used  only  for  transplants, 
and  it  is  then  best  to  change  the  species  grown. 

7.  Rhijtisma  acerinuin,  Fr. 
(Sycamore  Leaf-blotch.) 
This  fungus  causes  black  spots  on  the  leaves  of  maples, 
especially  of  the  Norway  maple  and  sycamore. 

During  damp  weather  iu  July,  round  yellowish  spots  \  to 

I  I  2 


I.  SI. 


■KOI  KCIION    ACAIXsr    KL\N<;l. 


^  inch  across  appear  on  niajjle  leaves,  and  turn  hlack  in 
Aii<^ust,  retaining  a  lighter  tint  on  their  herders.  The  leaves 
fall  earlier  than  is  usual.  On  the  fallen  leaves  during  winter 
and  the  following  spring  numerous  sporocarps  develop  on  the 
hlack  spots,  and  they  open  in  long  cracks  in  damp  weather. 
Tiie  spores  whieii  issue  from  tiiem  in  the  spring  germinate  on 


Fig.  23G. — lilnjtimna  acerhium,  Fr.,  on  ii  leaf  of  iVorway  Maple.     Tiie  dark  blotches 
(a)  are  siirrouuded  by  a  dead  lighter  coloured  zoue  {h). 


the  leaves  and  produce  fresh  spots  as  hefore.  The  parasite 
appears  to  he  an  annual,  and  is  very  common. 

The  damage  done  is  mostly  due  to  reduced  assimilating 
powers  of  the  leaves  and  is  relatively  unimportant. 

Where  the  dead  leaves  are  swept  up  and  burned,  as  in  parks 
and  gardens,  the  disease  does  not  spread,  but  in  places  where 
dead  maple  leaves  are  allowed  to  lie  about  in  ditches,  etc.,  it 
may  recur  annually  to  the  detriment  of  the  beauty  and  shade 
of  the  trees. 


WILLOW    LKAF-P.IJSTER. 


4S5 


8.  Mclampsora   Jfartif/ii,  Thiim. 

(Willow  Leaf-blister.) 
a.  Description  and  made  of  Allaclc. 


On  the  leaves  of  sever 
their  under  surface  and 
golden  -  coloured 
cushions,  subse- 
quently turning 
brown  and  then 
black,  may  appear 
at  the  end  of  May 
or  the  beginning  of 
June.  Leaves  which 
have  been  attacked 
soon  become  marked 
with  black  blotches 
and  fall  off;  the 
badly  infected  shoots 
also  die  from  their 
tips  downwards. 
The  sporofarps  hi- 
bernate on  the  dead 
leaves  lying  on  the 
ground  and  produce 
promycelia  and 
sporidia  in  the 
spring,  the  spores 
from  which  spread  l 
the  malady  by  ger- 
minating on  fresh 
leaves  and  shoots. 

The  same  disease 
infects  species   of   Rihen 
Caeoma     IlH>t'sii,    Link., 
unnecessurv   in    the    life 


al  species  of  willow,  and  especially  on 
the  ends  of  their  young  shoots,  little 


i-.  237.— *//,■.(■  acutifoUa,  Willd.,  attacked  by 

MeJampsnra  llailujii. 
II  Green  leaf  witli  orange  yellow  sporoearps. 
h  Leaves  with  black  patches,  withering. 
e  Sporoearps  on  the  epidermis  of  the  stem. 

(currant   or   gooseberry  plants),  as 
but     this     intermediate     stage    is 
of    the    fungus. 


486  PROTECTION    A<;AIXST    FUNCI. 

/'.  Si/hjeclft  of  Attack,  and  Distribution. 

The  fungus  which  occurs  in  Britain,  is  most  destructive  in 
its  attacks  on  the  Caspian  willow  (Salix  acutifolia,  Willd.),  but 
also  attacks  <S'.  daplinoidcs,  rimiualis,  purpurea,  etc.  Yearling 
shoots  suffer  most,  and  2  to  4  years  old  shoots  are  less  liable 
to  infection. 

c.  Prolcctivo  Rides. 

Cut  off  and  burn  all  infected  shoots  as  soon  as  they  are 
noticed.  All  infected  dead  leaves  should  he  collected  during 
the  autumn  or  spring  and  burned. 

Infected  osier-beds  may  be  sprinkled  by  means  of  an 
ordinary  white-washing  brush  with  dilute  carbolic  acid,  one 
part  to  500  of  water.  This  should  be  repeated  several  times, 
and  costs  about  Is.  an  acre.     Bordeaux  mixture  may  be  used. 

Cultivation  of  the  Caspian  willow  may  have  to  be  abandoned 
when  the  fungus  is  prevalent,  which  is  much  to  be  regretted  as 
this  willow  thrives  on  dry  soils  and  has  proved  useful  on  railway 
embankments,  sand-hills,  etc. 

Mclampsora  Salicis-Capreae,  Pers.,  is  common  on  S.  Caprcn, 
L.,  S.  nurita,  L.,  and  S.  cinerea,  L.,  and  develops  aecidia  of 
Caeoma  Eroni/)ui,  Gmel.,  on  the  spindle-tree. 


Fig.  23S. — Aspen  leaf  with  s])niocari)s  of  Melampsora  Tremulae,  Tul. 
After  Ilartiir. 


PART  IV. 

PROTECTION    AGAINST  ATMOSPHERIC    INFLUENCES. 


489 


PEOTECTION  AGAINST  ATMOSPHERIC 
INFLUENCES. 

FoKESTS  from  the  seedling  stage  up  to  maturity  are  subject 
to  the  influence  of  the  weather,  and  may  thus  l)e  injured  in 
various  ways.  The  chief  meteorological  phenomena  in  question 
are  frost,  heat,  wind  (especially  storms),  heavy  rainfall,  hail, 
snow,  rime  and  ice. 

As  a  matter  of  course,  these  phenomena  frequently  act 
beneficially  on  vegetation  ;  frost  disintegrates  the  soil  and 
prepares  it  for  the  reception  of  seed  and  the  growth  of  forest- 
plants  ;  the  wind  disseminates  the  seed  of  many  trees  and 
shakes  snow  from  off"  their  crowns  which  might  otherwise  be 
broken  l)y  its  accumulating  weight ;  atmospheric  precipitation 
and  heat  are  indispensal)le  for  vegetable  growth  ;  snow  is  a  bad 
conductor  of  heat,  it  keeps  the  soil  comj)aratively  warm  in 
winter,  and  protects  young  plants  from  frost.  Snow  also 
absorbs  much  air  and  with  it  carbon  dioxide ;  the  decomposi- 
tion of  mineral  matter  on  which  the  formation  of  soil  chiefly 
depends  is  expedited  l)y  carbon  dioxide,  so  that  winters  with 
heavy  snowfall  are  highly  advantageous  in  this  respect. 

Forest  Protection  has,  however,  less  to  do  with  the  beneficial 
action  of  these  i)henomena  than  with  the  damage  they  may 
inflict  on  fore.st  plants,  and  the  means  acquired  by  experience 
for  protecting  them. 

The  amount  of  damage  done  is  conditional  on  several 
circumstances.  In  the  first  rank  are  the  extent  and  intensity 
of  the  phenomenon,  but  the  season  and  the  state  of  the 
weather  before,  during  and  after  the  calamity  are  also  of 
importance. 

In  the  second  place,  the  nature  of  the  wood  and  locality 
should  be  considered ;  of  great  importance  are  the  species  of 
tree  grown,  the  system  of  management  of  the  forest,  and  the 
age  and  density  of  the  injured  woods,  as  different  species  and 
age-classes  siitt'er  in  different  decrees  from  bud  weather.     As 


490       I'KOTKCTIOX    AGAINST    AT.MOSl'HKKU'    IXF fAKN'CKS. 

regards  locality,  the  soil  and  configuration  of  the  ground 
affect  the  amount  of  damage  done,  as  they  determine  the 
energy  of  growth  of  the  forest  plants  from  their  youth  up.  The 
chief  points  here  are  the  chemical  and  physical  nature  of  the 
soil,  the  altitude  and  asftect  of  the  locality.  The  nature  of 
the  soil-covering  may  also  he  of  importance.  Since  then  all 
these  items  may  be  combined  in  a  great  variety  of  ways,  the 
damage  done  must  vary  greatly  according  to  circumstances. 

The  mode  of  occurrence  of  frost,  wind,  hail  and  snow 
should  be  studied  under  meteorology,  the  importance  of  a 
thorough  knowledge  of  which  to  the  forester  is  obvious.* 
More  or  less  complete  meteorological  observations  and  records 
have  been  made  during  the  last  twenty  years  at  the  German 
and  French  forest  experimental  stations.  Of  special  import- 
ance, as  regards  Forest  Protection,  is  a  steady  and  complete 
record  of  serious  damage  by  frost,  storms,  hail,  snow,  rime, 
either  in  one  of  the  registers  provided  for  by  a  working-plan, 
or  in  a  special  Record  of  forest  calamilies,  giving  not  only  a 
complete  account  of  the  area  affected  and  amount  of  damage 
done,  but  also  of  all  local  facts  that  favoured  or  attenuated  the 
evil.  The  results  of  the  protective  measures  adopted  must 
also  be  narrated.  Localities  specially  liable  to  damage  by 
frost,  storms,  or  snow,  should  be  marked  in  special  colours  on 
the  range  maps. 

By  circulating  suitable  directions,  and  by  adopting  a  uniform 
system  of  recording  facts,  tlie  compilation  of  a  general 
account  of  experience  in  various  forest  districts  will  be 
considerably  facilitated. 

*  Among  imiiierous  works  on  meteorology,  the  following  may  be  referred  to  : 
Mohn,  H.,  "ariindzuge  der  Meteorologie.''  nth  edition,  with  24  charts  and 
4.j  woodcuts.  Berlin,  l«y.S.  Hann,  Julius,  "  Handbucii  der  Klimatologie." 
Stuttgart,  1897.  English  translation  by  Robert  De  Oourcy  Ward.  London, 
Macniillnn  &  Co.,  1903.  Davis' " Meteorology."  Boston,  1893.  "Meteorology," 
Encyclopfedia  Britannica,  Vol.  xxx. 


491 


CHAPTER   I. 

PROTECTION    AGAINST    FROST. 

As  regards  its  distribution,  frost  may  be  either  widespread 
or  local ;  as  regards  season,  earhi  frosts  occur  in  the  autumn 
and  late  frosts  in  the  spring.  Early  or  late  frost  may  be 
either  widespread  or  local.  Late  frosts  are  commoner  in 
Europe  than  early  frosts,  and  occur  chiefly  in  lowlands,  early 
frosts  being  more  prevalent  in  mountainous  regions.  The 
extensive  damage  done  by  late  frosts  is  due  not  only  to  their 
frequency,  but  also  to  the  susceptibility  of  plants  during  the 
revival  of  vegetation  in  the  spring.  Frosts  in  May  are  usually 
most  fatal,  June  frosts  being  rare.  April  frosts  are  less 
dangerous,  vegetation  not  being  sufficiently  advanced  to  suffer 
greatly.  In  the  Xortli-Vv'est  of  India,  early  frosts  usually 
do  most  damage,  as  the  bright  days  and  cold  nights  of 
November  sometimes  involve  daily  ranges  of  temperature 
of  40°  and  even  50^  F.,  that  are  fatal  to  the  sappy  shoots 
of  trees. 

Winter-frosts  in  Europe  rarely  injure  indigenous  trees, 
though  they  may  kill  unprotected  exotic  evergreen  plants 
such  as  laurels,  etc.  The  mild  winters  experienced  in  the 
west  of  France  and  of  the  British  Isles,  render  possible  tlie 
outdoor  cultivation  of  many  plants  whose  natural  habitat 
is  further  south,  and  which  would  succumb  to  the  severe 
winters  of  more  easterly  European  countries,  as  was  the  case 
with  the  common  gorse,  and  many  exotics,  in  Surrey,  in 
1895.  Seeds  have  been  subjected  to  temperatures  of  liquid 
air  (—180''  C.)  for  110  hours  without  injury,  germinating  just 
as  freely  as  other  test  seeds  not  so  treated  (Mr.  Horace  Brown 
and  Prof.  Dewar,  1897). 

Frost  damages  forest-plants  in  four  ways  : — 
i.  By   freezing    to    death   young  woody   plants    or   young 
organs  of  plants. 


492  PROTPX'TIOX    AGAIXST    FROS'I'. 

ii.  Splittinf;  tlio  stems  of  trees. 

iii.  Causliif^  canker  in  stems  of  troes. 

iv.  Tprootinf^  younp;  plants. 

Section  I. — Frozen  Plant-Organs.* 
1.  External  Appi'arancc  of  Injiirrd  l*la)its. 

Frozen  plants,  or  organs  of  plants,  become  soft,  flexible  and 
hang  down  or  wilt.  When  dead  they  eventually  turn  brown 
or  black.  These  outer  signs  result  from  the  reduced  tension 
of  the  tissues  injured  by  frost,  and  from  their  inability  to  fulfil 
their  proper  functions.  Foliage  frequently  falls  prematurely 
owing  to  early  frosts,  a  film  of  ice  forming  at  the  base  of  the 
petiole,  as  in  robinia  and  elder,  which  may  become  leafless 
in  a  few  days,  the  fallen  leaves  remaining  quite  green  and 
apparently  unaffected  by  the  frost.  In  other  trees,  as  horn- 
beam, beech  or  oak,  the  frozen  foliage  may  die  and  turn 
brown,  and  remain  on  the  tree  until  the  buds  swell  in  the 
spring,  the  normal  autumnal  leaf-fall  being  prevented  by  the 
fact  that  the  leaf  is  killed  before  the  usual  layer  of  cork,  which 
causes  defoliation,  has  formed  at  the  base  of  the  petiole. 

M.  Mer  relates  ("Rev.  des  E.  et  F.,"  July,  1897,  p.  424) 
that  in  a  frost  in  February,  1895,  in  the  Hautes  Yosges,  near 
the  Lake  of  Longemer,  young  silver-fir  attacked  by  frost  did 
not  lose  their  lower  branches,  which  were  protected  by  snow, 
while  their  middle  branches,  above  the  snow,  were  killed. 
The  buds  of  the  two  or  three  highest  verticils  remained 
dormant  for  a  year,  producing  no  shoots  in  1895,  and  some 
of  them  not  even  in  189G,  whilst  the  terminal  bud  produced  a 
leader  in  the  summer  succeeding  the  frost.  Hence  it  appears 
that  organs  may  be  aft'ected  by  frost,  without  being  killed, 
and  that  the  most  vigorous  organs,  such  as  terminal  buds, 
best  resist  frost. 

2.  Kxidanation  of  the  Action  of  Frost. 
Death  by  freezing  is  usually  caused  by  late  frosts,  less  by 
early  frosts.     Winter  frost  rarely  kills  indigenous  plants. 

*  Goppcrt,    Dr.    II.   It.,  ••  Ucber  das  Gefriercn,   Erfricren  der   r(lanzc7i   und 
Scliiitziiiittel  dii,i,regcii."     Stuttpirt,  1SS3. 


KKO/KX    I'LANT-ORGANS.  [W-i 

The  death  by  freezing  of  plants,  or  certain  parts  of  plants, 
is  usually  due  to  a  rapid  thaw  rather  than  to  the  direct  effects 
of  the  low  temperature  to  which  they  have  been  exposed. 
This  is  because,  owing  to  the  low  temperature,  the  liquid 
contents  of  tlie  affected  tissues  becomes  denser,  and  a  change 
ensues  in  them.  The  cell-sap,  when  converted  into  ice, 
expands  10  per  cent.,  and  sets  free  part  of  the  air  which  it 
contains  ;  this  increases  the  size  of  the  pores  and  the  per- 
meability of  the  membranous  lining  of  the  cell-wall,  which 
loses  its  powers  of  resistance  to  the  passage  through  it  of 
certain  substances,  and  allows  the  cell-sap  to  pass  into  the 
intercellular  spaces  of  the  plant,  where  it  freezes.  The 
injured  tissues  thus  become  limp  from  loss  of  water. 

A  similar  result  happens  in  the  case  of  frozen  starch-paste, 
in  which  the  water  and  starch  become  separated,  and  will 
not  reunite  after  a  thaw.  The  air  escaping  from  the  frozen 
tissues  may  also  decompose  the  chlorophyll,  and  hence  the 
brown  and  eventually  black  colour  of  the  dead  organs.  If, 
however,  the  ice  formed  in  the  intercellular  spaces  thaws 
slowly,  the  cell-wall  may  recover  its  normal  elasticity  and 
reabsorb  the  water  before  the  chlorophyll  has  decomposed. 
With  a  rapid  thaw  this  is  impossible,  as  the  water  then  remains 
in  the  intercellular  spaces,  and  death  ensues. 

The  effect  of  allowing  the  thawed  water  to  become 
reabsorbed  may  be  well  observed  in  a  meadow  after  a  sharp 
frost  in  May,  when  the  grass  has  been  in  full  growth.  No 
bad  results  follow  from  the  frost,  unless  men  or  animals  tread 
on  the  frozen  grass,  but  wherever  they  do,  the  crushed  grass 
appears  black  and  dead,  as  if  singed  by  a  red-hot  iron.  This 
is  because  the  crushed  tissues  will  not  allow  the  return  of  the 
sap  when  the  thaw  sets  in.  The  more  water  an  organ  or  plant 
contains,  the  more  it  is  subject  to  be  frozen.  The  old  theory 
that  plant-cells  are  split  by  the  freezing  of  the  cell-sap,  and 
consequent  expansion  of  the  ice,  is  not  true :  in  the  first 
place,  the  cell  is  not  filled  with  sap,  and  secondly,  the  cell- 
wall  is  sufldciently  expansible  to  resist  an  extension  of  iV.th 
of  its  volume,  supposing  it  were  full  of  sap  and  the  sap 
converted  into  ice. 

Hartig  states  that  cortex  and  bast  containing  concentrated 


•19  !•  I'ROTKCTIOX    A(iAlXST    FROST. 

sap  do  not  freeze  so  readily-  as  3'oung  wood  and  leaves,  wliich 
contain  a  more  Avatery  sap,  and  which,  owinj^  to  the  scarcity 
of  intercellular  spaces  in  wood,  turn  to  ice  within  the  lumina 
of  the  cell,  at  the  same  time  depriving  the  cell-walls  of  their 
water  and  causing  them  to  shrink. 

Severe  frost  may  thus  impair  the  young  zones  of  sapwood 
in  a  tree  without  killing  the  cambium.  The  formation  of 
heartwood  may  thus  he  hindered  and  several  zones  remain 
intermediate  between  sapwood  and  heartwood,  forming  a  ring- 
shake  in  tlie  wood.  Or  the  sapwood  may  be  actually  killed 
and  separated  from  the  cambium,  which  continues  the  circum- 
ferential growth  of  the  wood  outside  the  dead  wood,  so  that 
after  the  tree  has  been  felled  the  inner  portion  may  be  found 
completely  separated  from  its  outer  zones  by  cup-shake. 

Molisch  agrees  w'ith  H.  Miiller  Thurgau  in  the  theory  that 
Sachs'  view  that  rapid  thaw  kills  plants  is  not  generally 
correct.  Hess,  however,  considers  that  the  results  of  experi- 
ence in  vineyards  and  forest  nurseries  are  strongly  in  favour  of 
Sachs'  view,  and  also  states  that  Thurgau  has  reconsidered 
his  opinion,  and  has  shown  that  a  frozen  plant  may  be  saved 
l)y  slow  thawing,  that  would  certainly  be  killed  if  thawed 
rapidly.* 

3.  Amount  of  Damage  done. 

a.  General  Nature  of  Damafie. 
Late  and  early  frosts  often  kill  young  plants  and  destroy  the 
foliage,  shoots,  blossoms  or  young  fruit  of  trees.  This  retards 
their  upward  growth,  causes  a  loss  of  increment  and  reduction 
in  quantity  or  complete  loss  of  the  crop  of  fruit;  thus  the 
management  may  be  impaired,  especially  when  natural 
regeneration  is  desired.  Early  frosts  hinder  the  complete 
ripening  of  the  wood,  especially  in  coppice-shoots;  by  the 
early  fall  and  killing  of  leaves  forest  trees  suffer  a  loss  in 
potash  and  phosphoric  acid,  if  these  substances  have  not 
completely  returned  to  the  stem,  as  they  do  before  the  normal 
leaf-fall.  Owing  to  the  narrow  annual  zones  of  wood  which 
are  formed  in  years  of  severe  frost,  they  may  be  recognised  on 

*  Molisch,  H.,  ••  Untersucliungeu  iiber  das  Eifiieien  der  I'tiaiizen.''  Jena, 
181*7. 


FROZEN    PLANT-ORdANS.  1-95 

an  inspection  of  a  cross-section  of  a  stem.  Frost  also  causes 
certain  forms  of  canker  in  broadleaved  trees. 

Tlie  physiological  etYects  of  severe  winter-frost  consist  chiefly 
in  killing  wood  which  is  not  full_y  ripe,  and  which  has  been 
spared  by  the  early  frosts.  In  this  way,  either  the  youngest 
shoots,  the  autumnal  woody  zone,  or  the  whole  annual  ring  of 
wood  inside  the  cambium-zone  may  suffer  and  cause  cup-shake 
in  wood.  Where  cup-shake  is  thus  caused,  the  concentrated 
sap  in  the  cambium-zone  preserves  it  from  damage,  wliile  the 
zone  of  the  sapwood  next  to  it  becomes  so  dried  by  the  freez- 
ing of  the  sap  within  it  as  to  separate  partially  or  entirely 
from  the  cambium.  Mechanical  injuries  done  by  winter-frost 
will  be  described  further  on. 

The  damage  done  under  the  headings :  species,  tree-part, 
system  of  management,  age,  locality,  soil-covering,  density  of 
stock,  and  weather  will  each  be  considered  separately. 

//.  Spcrii's  of  Tree. 

As  a  rule,  broadleaved  trees  are  more  susceptible  to  frost 
than  conifers,  and  species  which  prevail  in  the  south  suffer 
more  than  those  from  the  north.  As  special  conditions  affect- 
ing the  extent  of  the  damage  done  by  frost,  the  degree  of 
development  and  power  of  recovery  of  the  plant  are  important. 
Thus  the  beech  and  oak  are  equally  liable  to  injury  by  frost, 
but  tiie  oak  suffers  less  than  the  i)eech,  as  it  shoots  out  later 
in  the  spring. 

As  regards  recovery  from  damage,  the  oak  is  also  more 
favoured  than  the  beech,  for  if  its  leader  be  frozen,  lateral 
buds  develop  new  leaders,  but  the  beech  having  fewer  dormant 
buds  cannot  do  this  so  well.  The  oak  can  also  put  out  a 
second  foliage  during  the  year  if  the  first  be  frozen,  but  the 
beech  cannot.  Hence  wood-formation  is  less  hindered  in  the 
oak  than  in  the  beech.  Similar  considerations  affect  other 
species.  As  regards  conifers  indigenous  in  Central  Europe, 
the  silver-fir  is  most  susceptible,  but  I  have  had  a  bed  of 
yearling  silver-fir  at  Coopers  Hill,  quite  unprotected  during 
the  winter  1902-3,  and  planted  them  out  safely  under  cover  in 
spring.  Older  silver-fir  in  the  nursery  had  their  young  shoots 
severely  frozen  in  the  spring. 


1-96  I'KOTECTIOX    A(;A1X.s|-    KKosT. 

A  classification  of  woody  plants  according  to  their  suscepti- 
bility to  frost  is  not  impossible,  but  can  only  be  of  local  value, 
as  the  earlier  or  later  shooting  out  of  a  tree  depends  on  the 
altitude,  as  well  as  on  the  species  grown. 

The  following  list  groups  trees  according  to  their  suscepti- 
bility to  late  and  early  frosts  : — 

i.  Very  Fiiusi-tendi:k  Spkciks. 
Ash,  walnut,  plane,  sweet  chestnut,  beech,  oaks,*  robinia 
(early  frosts),  silver-fir. 

ii.  Moderately  Frost-texdeu  Specie-s. 
Sj'camore,  Norway  maple,  Salix  viminalis,  L.,  spruce,  larch, 
cluster  pine.     In  many  localities,  spruce  suffers  so  severely  as 
to  be  placed  in  group  i. 

iii.  Frost-haudy  Si-ecies. 

Hornbeam,  elms,  rowan,  aspen,  poplars,  willows  (except 
,S'.  viminalis,  L.),  alders,  birches,  horse-chestnut,  limes,  hazel; 
Scots,  Black,  Weymouth,  Cembran  and  mountain  pines ; 
juniper. 

In  the  case  of  very  severe  late  frosts,  species  in  the  last 
group,  such  as  the  Scots  pine,  may  suffer,  or  be  killed  when 
quite  young. 

If  the  locality  be  taken  into  account,  as  sea-coast,  flat,  hilly, 
or  mountainous  land,  some  modifications  must  be  made  in  the 
above  groupings. 

In  general,  local  trees  which  shoot  out  early  are  more  or 
less  frost-hardy,  for  instance,  tlie  birch,  alder,  and  sallow; 
frost-tender  species  such  as  the  oak  and  ash  shoot  out  later  in 
the  spring,  and  the  beech,  which  shoots  earlier  than  either, 
owes  its  immunity  from  frost  to  its  power  of  resisting  cover 
under  which  spring  frosts  do  not  occur.  The  faculty  of  pro- 
ducing adventitious  buds  (oak  and  silver-fir)  is  helpful  to  those 
species. 

The  larch,  which  shoots  out  early  in  the  spring,  suffers  in 
low  situations  from  late  frost. 

*  Some  North  American  oaks  and  ash-tvces  suffer  less  than  European  species  ; 
Turkey  oak  is  less  hardy  than  either. 


FROZEN    PLANT-ORGANS.  V.)7 

As  regards  extreme  winter-cold  the  following  somewhat 
different  scale  applies  : — 

i.  Very  Fikjst-tendku  Si-ecies. 
Sweet  chestnut,  plane,  walnut,  many  fruit  trees,  such  as 
apricot,  peach,  quince  and  cherry.* 

ii.    SOMF.WII.VT    Fko.ST-TKN'UEU    Si'EclKS. 

Pedunculate  and  sessile  oaks,  ash,  elms,  beech,  rohinia, 
silver-fir,  yew. 

Frost- hard ij  Spcrios. 

Maj^les,  horse-chestnut,  lime,  poplars,  willows,  hornbeam, 
birch,  alders,  Pi/riis  sp.,  hazel;  spruce,  Scots,  AVeymouth, 
Mountain  and  Cembran  pines,  larch,  juniper. 

Pyramidal  poplar  is  the  least  hardy  of  the  poplars,  rowan 
least  hardy  of  the  Pyrus  sp.  The  Weymouth  pine  may  send 
out  second  shoots  in  summer,  which  are  usually  killed  in 
autumn  or  winter. 

.As  regards  the  susceptibility  of  exotic  trees  that  have  been 
introduced  into  Central  Europe,  the  following  experience  has 
been  gained  in  Germany  : — 

A.  Susceptibility  of  Exotic  Trees  to  Late  and  Early  Frost. 

i.    VeUY    FUOST-TENUEII    Sl'ECIES. 

Black  walnut,  all  hickories,  Turkey  oak  ;  Abies  Nordman- 
fiicuia,  Spach.  (Caucasus),  Douglas  fir,  Jeffrey's  pine,  Pinus 
poiuIiTosa,  Laws. 

Black  walnut  is  slightly  less  susceptible  than  common 
walnut.  Carya  amara,  Nutt,  is  the  hardiest  hickory.  Nord- 
mann's  fir,  sprouting  late,  is  less  susceptible  than  common 
silver-fir. 

ii.  Fkost-tenuek  Species. 

American  ash,  grey  walnut  {Juglans  cineren,  L.),  sugar  maple, 
Californian  maple  {A.  circinatum,  Pursh.)  ;  Sitka  (or  Menzies) 
spruce,  Corsican  pine,  Japanese  larch. 

•  Apricots  and  peach  trees  are  killed  by  2G° — 3U°  C,  walnut  by  'Mf — 32°  C, 
tlie  cheiry-tVL'e  by  31°     :?'2°  C. 

F.P.  K  K 


498  PROTKCTION    ACAIXST    KliOST. 

iii.  FuosT-iiAiiDY  Species. 

Canadian  poplar,  cherry  l)irch  (Betnla  hiiia,  L.),  white 
spruce,  Finns  rir/iiht,  I\Iiil  (pitch  pine),  Lawson's  cypress, 
Seqnoia  WcUinfitoNtd,  Seem.,  red  cedar  (JiiniperiiH  rini'nii- 
aiia,  L.)- 

Young  seedlings  of  pitch  pine  are  occasionally  hilled  by 
early  frosts.  Lawson's  cypress  and  Wellingtonia  are  somewhat 
susceptible  to  frost  for  the  first  4 — 5  years. 

B.  Susceptibility  of  Exotic  Species  to  Winter-Frost. 
It  appears  useless  to  give  Hess'  list  of  delicate  species,  as  it 
includes  some  plants  that  are  quite  hardy  in  the  British  Isles. 

Fiosl-hardy  Species. 

Red  oak,  ashleaved  maple,  sugar  maple,  American  ash,  all 
hickories,  cherry  birch,  Canadian  poplar,  Nordmann's  fir, 
Balsam  fir,  Douglas  fir,  Sitka  spruce,  white  spruce,  Vinus 
punderusa,  Laws.,  Japanese  larch,  Lawson's  cypress,  "Welling- 
tonia, red  cedar. 

From  these  lists,  it  appears  that  the  introduced  exotics 
hardly  suffer  more  from  frost  than  indigenous  species.  Several 
species  not  mentioned  by  Hess,  such  as  Thuja  (jigantea,  Nut- 
tall  {T.  lAicata,  D.  Don.,  according  to  Sargent),  Taxodium 
disticlium,  Eich.,  are  frost-hardy  in  Britain.  In  the  west  of 
the  British  Isles  numerous  species  thrive,  which  cannot  with- 
stand the  frosts  of  Central  Europe,  or  even  of  the  eastern 
counties  of  Great  Britain. 

r.  Part  of  Tree. 
The  inflorescence,  opening  leaves  and  young  shoots  suffer 
most ;  the  developed  leaves  and  needles  less,  and  least  of  all 
the  buds.  In  silver-fir  and  spruce  the  damage  is  nearly 
always  confined  to  the  spring-shoots,  the  old  needles  escape, 
and  as  in  the  silver-fir  tlue  terminal  buds  open  out  later  than 
the  lateral  buds,  the  latter  are  more  often  frozen. 

d.  SijHieiit  of  Managemeitl. 
Coppice,  especially  with  short  rotations,  suffers  more  than 
high-forest,    as    the    susceptil>le    young    growth    occurs    so 


FROZEN    PLAXT-OROAN8.  499 

frequently.  If  the  cutting  of  coppice  is  delayed  in  the  spring, 
the  annual  shoots  may  not  he  completely  lignified  before  they 
are  exposed  to  early  frosts.  The  underwood  in  coppice-with- 
standards  suffers  less  than  simple  coppice,  owing  to  the  slielter 
afforded  by  the  standards.  The  various  shelterwood  systems 
constantly  afford  shelter  to  young  growth,  and  are  therefore 
less  liable  to  danger  from  frost,  than  the  systems  of  Coppice 
and  of  Clear-cutting  in  High  Forest. 

e.  Aye  of  Wood. 

Woods  are  most  exposed  to  danger  in  youth,  especially 
during  the  sprouting  of  the  seed  ;  a  single  frosty  night  at  this 
period  may  at  once  annihilate  the  results  of  a  forester's  care. 
The  chief  danger  continues  until  the  young  plants  have  grown 
above  the  local  frosty  zone.  As,  however,  this  varies  accord- 
ing to  the  configuration  of  the  ground,  a  scale  of  susceptibihty 
for  each  species,  according  to  age,  cannot  be  attempted. 

Quick-growing  species  in  breezy  hilly  localities  are  most 
favourably  situated,  while  slow^-growing  tender  plants  in  valle3's 
and  plains  suffer  most. 

In  the  case  of  widely-spread  frosts  and  exceptionally  low 
temperatures,  the  leaves  and  shoots  of  taller  trees  may  suffer. 

/".  Localilij. 

The  following  localities  are  specially  liable  to  injuries  by 
frost : — 

i.  Damp,  low-lying  places  with  stagnating  air,  for  instance, 
narrow,  closed-in  valleys,  or  small  depressions  in  the  ground, 
termed  frost-hollows.  In  such  places,  frost-hardy  species  such 
as  hornbeam,  aspen,  and  birch  are  naturally  invasive,  whilst 
the  more  valuable  species  become  stunted,  and  there  is  gene- 
rally a  plentiful  coating  of  lichens  on  the  trees.  If,  in  such 
depressions,  the  soil  is  moist  or  wet,  or  there  are  water-courses 
or  swamps  near  at  hand,  the  evaporation  of  the  water  still 
further  reduces  the  temperature,  whilst  owing  to  the  absence 
of  air-currents  the  cold  air  is  not  replaced  by  warmer  air  from 
the  neighbourhood.  If,  on  the  contrary,  the  soil  is  dry,  the 
plants  become  cooled    by  their   own  radiation,  and    by    the 

K  K  2 


500  I'RO'IKCTION    A<;AIXST    FROST. 

descent  of  liea\A-,  cold  air  from  aljove,  which  collects  like 
a  lake  over  the  low  ground  and  causes  sharply-defined 
frost-limits. 

ii.  Woods  on  north-easterly,  easterly,  south-easterly  or 
southerly  as^Deets  suffer  most  from  frost ;  on  the  two 
former  aspects,  hecause,  unless  sheltered  hy  a  hill,  they  are 
exposed  to  cold  frosty  winds,  whilst  tlie  sudden  exposure  to 
the  sun's  rays  after  sunrise  increases  the  danger  of  easterly 
aspects.  On  south-easterly  and  southerly  aspects  growth 
hegins  earHer  in  the  spring  than  on  colder  aspects,  prolonging 
the  period  of  exposure.  On  south  aspects  "the  variations  of 
temperature  are  also  greater  than  on  cooler  aspects.  Northerly 
and  westerly  aspects  are  least  exposed  to  injur}-  by  frost. 

iii.  High  plateaux  are  more  heated  b}-  the  sun  than  low- 
lands, where  the  atmosphere  is  denser  ;  vegetation  on  them  is 
therefore  more  precocious.  But  the  radiation  of  heat  at 
night  is  greater  than  in  lowlands,  and  consequently  there  is  a 
greater  range  of  temperature,  while  woody  plants  stand  sudden 
changes  from  heat  to  cold  worse  than  intense  cold. 

As  a  rule,  valleys,  lowlands,  and  plateaux  suffer  more  from 
frost  than  hills  and  mountain  sides. 

iv.  Wet  impermeable  soils,  such  as  cold  clays,  induce  low 
air-temperature,  and  frost  holds  out  longer  there.  The  richer 
and  deeper  the  soil,  the  more  quickly  do  plants  recover  from 
freezing  and  grow  out  of  the  reach  of  frost. 

//.  Naltirc  of  Soil-rovorinti. 
A  dense  and  high  growth  of  grass  and  herbage  increases  the 
danger  from  frost,  as  it  prevents  the  soil  from  being  heated, 
diminishes  the  circulation  of  the  air,  and  reduces  the  tempera- 
ture by  transpiring  moisture  and  radiating  heat.  From 
observations  made  at  Yiernheim  in  Hesse,  the  temperature 
over  an  area  covered  with  grass  may  be  16"  F.  lower  than 
on  a  plot  of  similar  land  b»re  of  vegetation.  On  the  other 
hand,  a  lightly  shading  growth  of  birch,  sallow,  thorns,  broom, 
etc.,  will  reduce  radiation  and  thus  preserve  from  frost  plants 
of  valuable  species  which  may  be  growing  among  the  woody 
undergrowth.  Under  conditions  otherwise  the  same,  frost 
penetrates  more  slowly  and  less  deeply  into  a  soil  covered  with 


FKOZKN    I'LAXT-ORGANS.  501 

humus,  dead   leaves,  etc.,  than  on  bare  soil,  though  in  the 
former  case  the  frost  remains  longer. 

It.  Density  of  Sfock. 

Natural  regeneration-areas  as  well  as  plantations  and  sow- 
ings under  a  shelterwood,  which  reflects  back  the  radiated 
heat  towards  the  ground,  whilst  the  crowns  of  the  shelter 
trees  prevent  rapid  changes  of  temperature,  suffer  much  less 
from  frost  than  sowings  and  plantations  in  the  open.  Young 
plants  suddenly  exposed  by  the  removal  of  a  shelterwood  are 
highly  susceptible  to  damage  by  frost,  and  large  areas  of 
spruce  6  feet  in  height  may  i)e  thus  killed. 

Damage  by  frost  is  much  less  in  well-stocked  woods  than 
where  blanks  or  thinly-stocked  places  occur.  Unrestricted 
radiation  of  heat  and  non-circulation  of  the  air  expose  such 
places  to  frost ;  in  the  same  way  young  growth  surrounded  by 
tall  woods  is  often  frozen. 

/.  Stall'  of  I  lie  Woatltor. 

The  clearer  the  sky  during  day-time  and  the  brighter  the 
night,  the  greater  is  the  danger  from  frost,  especially  with  an 
east  wind.  It  seldom  freezes  with  a  cloudy  sky,  as  then  the 
heat  radiated  fi-om  the  ground  is  reflected  back  again  by  the 
clouds.  Late  frosts  accompanied  by  rime  are  more  dangerous 
than  black  frosts,  as  the  coldness  of  the  air  is  still  further 
increased  by  the  evaporation  of  the  frozen  dew.  In  a  pro- 
longed frost,  accompanied  by  cold  dry  winds,  the  frozen  iwigs 
may  be  dried  up  and  killed.  A  wet  autumn  generally 
increases  the  subsequent  bad  effect  of  the  winter's  cold. 

As  a  rule,  in  Central  Europe,  all  danger  from  frost  is  over 
by  the  middle  of  May,  but  exceptions  may  occur,  and  in  181)2 
the  grass-temperature  at  Coopers  Hill,  in  Surrey,  from  the 
13th  to  the  16th  June,  varied  between  25"  and  32'  F., 
so  that  potato-shoots  and  bracken  were  frozen  and  killed 
in  the  neighbourhootl.  In  mountainous  regions,  late  frosts 
are  to  be  feared  till  July.  In  the  north  of  India,  night- 
frosts  may  occur,  on  clear  nights,  from  October  till  the 
end    of     March,    and    they    cause    considerable    damage    to 


502  I'HO'I'KCTION    AGAINST    FROST. 

Sal  {SJiorea  mhiista)  and  other  winter -green  and  ever  green 
trees.*  Very  extensive  damage  was  done  to  sai^lings  and 
poles  in  N.-W.  India  by  severe  frost  in  February,  1905. 

4.  licgistcr  of  Severe  Frosts. 

Damage  by  frost  is  usually  local.  There  are,  however, 
years  in  which  damage  is  done  over  extensive  areas,  these 
years  being  termed  frost-ijears.  The  dates  below  refer  solely 
to  frost-years. 

In  Central  Europe,  during  the  fifty-two  years  from  1848  to 
1899,  severe  late  frosts  occurred,  on  the  average,  every  other 
year  ;  the  worst  years  for  persistence  and  severity  of  these 
frosts  being  1854,  1866,  1876,  1878,  1880  and  1894.  Not  a 
single  month  is  absolutely  free  from  frost,  not  even  July  or 
August.  On  May  21st,  1894,  the  foliage  of  the  oak  standards 
in  the  lower  ground  of  Prince's  Coverts,  near  Esher,  in  Surrey, 
was  entirely  destroyed  by  frost,  whilst  much  damage  was  also 
done  to  the  ash  and  other  underwood  ;  the  crowns  of  the  oak 
trees,  which  were  blackened  by  the  frost,  did  not  become 
completely  green  again  till  the  middle  of  July.  A  similar 
event  happened  in  the  Forest  of  Dean  on  May  29th,  1819. f 

In  Central  Europe,  during  the  present  century,  there  has 
been  one  hard  winter  every  five  or  six  years,  the  coldest  years 
previous  to  1895  being  1829-30  and  1879-80,  when  atGiessen, 
on  the  10th  December,  1879,  and  in  February,  1880,  tempera- 
tures of  31°  and  25°  below  zero,  F.,  were  observed.  The  lowest 
temperatures  measured  at  Coopers  Hill  were  16°  F.,  in 
December,  1879,  and  10°'l,  in  February,  1895.  Lough- 
borough is  one  of  the  coldest  places  in  Britain,  and  its  minima 
on  the  8tli,  9th,  and  10th  February,  1895,  were  5°,  4°  and  1° 
below  zero,  F.  During  1895,  the  frost  continued  night  and 
day  at  Coopers  Hill  from  January  25th  to  February  18th, 
and  skating  lasted  till  the  middle  of  March. 

5.  Protective  Measures. 
Protective  measures  against  fi'ost  may  l)e  taken  during  the 
formation  and  utilisation  of  woods. 

*  Many  trees  in  India  lose  their  leaves  in  tlie  spring  after  retaining  them 
throughout  the  winter. 

t  "The  Forest  of  Dean,"'  by  H.  0.  NichoUs.     J.  Murray.  London.     18.W. 


FROZEN    PLANT-OROANS.  503 

a.  Diivinti  flip  Fnnnatinn  of  Woods. 

i.  Drain  wet  places  and  all  swamps  in  the  forest  l)efore 
restockinfr. 

Moisture  is  not  always  favourable  to  frost,  for  Wollny 
states  that  dry  humus  has  a  low  specific  heat  and  is  a  bad 
conductor,  while  wet  humus  has  a  high  specific  heat  and  is  a 
good  conductor.  In  accordance  with  this  principle,  cranberry 
swamps  in  Carolina  are  irrigated  during  the  blossoming 
period,  when  frost  is  feared  ;  also,  in  Northern  India,  vegetable 
gardens  and  sugar-cane  crops  are  irrigated  in  order  to  obviate 
danger  from  frost.  In  sphagnum  peat-bogs,  a  thin  layer  of 
peat  is  left  at  the  base  of  the  bog,  when  the  peat  is  cut,  in 
order  to  reproduce  the  peat,  and  unless  this  is  kept  wet,  frost 
and  drought  kill  the  peat. 

ii.  Abandon  attempts  to  grow  frost-tender  species  in  the 
open.  Such  species  as  beech  and  silver-fir  should  not  be 
grown  ill  bad  frost  localities,  and,  in  any  case,  should  be 
protected  by  planting  beforehand,  or  simultaneously  with 
them  as  nurses,  fast-growing  hardy  trees,  such  as  Scots  pine, 
larch,  birch,  or  white  alder. 

iii.  Natural  regeneration  under  a  shelterwood  and  keeping 
seeding-cuttings  dark  should  be  preferred,  especially  on  easterly 
or  southerly  aspects.  Low,  branching  shelter-trees  should  be 
pruned  to  promote  air-circulation. 

iv.  Strong  transplants  should  be  used,  plants  with  balls  of 
earth  and  mound-planting  being  preferable  for  frost  localities. 
On  wet  ground,  ridge-planting  may  be  adopted. 

V.  Protective  belts,  30  to  40  feet  wide,  of  spruce,  or  Scots 
pine,  may  be  established  along  the  easterly  boundaries  of 
a  wood. 

vi.  Where  areas  to  be  restocked  are  covered  with  a  dense 
growth  of  grass  or  herbage,  this  should  be  removed  before 
planting  or  sowing  is  attempted. 

vii.  Transplants  should  be  lifted  from  the  nursery  early 
in  the  planting  season  and  heeled-in  in  shady  places  near  the 
area  to  be  planted,  in  order  to  delay  their  sprouting.  Silver- 
lir  planted  out  late  in  the  spring  suffers  less  from  May  frosts 
tlian  spruce  planted  out  early  or  in  the  previous  autumn, 
becaut^e  its  l)uds  open  later. 


50 !•  I'HorKCTIOxN'    AOAIXST    FROST. 

viii.  AVherevei-  frosts  are  to  be  feared  in  forest  nurseries, 
the  following  rules  should  be  observed: — 

They  should  be  situated  on  northerly  or  north-westerly 
aspects. 

Seed  should  not  be  sown  too  early,  say  before  the  1st 
of  May  ;  it  should  be  well  covered. 

In  autumn,  beds  of  seedlings  may  be  covered  with 
brushwood,  and  seed-beds  with  dead  leaves,  moss,  or 
saw-dust.  In  spring,  brushwood  or  shelter-mats  may  be 
used.  These  latter  may  be  placed  on  liglit  wooden 
supports  and  can  then  be  removed  and  replaced  at  will. 
Smoky  fires  may  be  kindled  during  the  night,  the 
clouds  of  smoke  preventing  radiation  from  the  ground. 
This  practice  is  extensively  followed  in  French  vineyards, 
coal-tar,  or  small  boxes  filled  with  refuse  resin,  being 
burned. 

Plants  which  are  covered  with  rime  may  be  watered  with 
cold  water  before  sunrise  so  as  to  delay  their  thawing. 
Nurseries  should  be  kept  free  of  weeds.* 
(ix.)  Tender  ornamental  evergreen  plants  may  be  wrapped 
up  during  winter  in  matting  or  straw,  until  they  have  grown 
beyond  the  reach  of  frosts.     The  so-called  hardening  of  trans- 
plants which  have  been  a  few  years  in  the  ground  is  due  to 
the  fact  that  their  roots  get  gradually  deeper  into  the  soil,  and 
conduct  the  heat  of  the  soil  to  the  plants  better  than  superficial 
roots.     Covering  the  base  of  transplants  with  cinder-dirt  or 
dead  leaves  also  protects  them  from  frost. 

All  parts  of  plants,  which  in  spite  of  these  precautions  have 
been  killed  by  frost,  should  be  pruned,  and  frozen  plants,  such 
as  oak-saplings,  which  have^  collum-buds,  may  be  cut  back 
level  with  the  ground.  Dead  conifers  and  plants  like  beech, 
wdiich  coppice  badly,  must  be  pulled  up  and  the  vacant  spots 
replanted  with  strong  transplants. 

h.   Ihirinij  flip  Tendinij  of  Woods. 
i.  Prune  all  stems  of  their  lower  branches  that  stand  over 
young  growth,  both  in  high  forest  and  coppice-with-standards, 

*  Mr.  \V.  Forbes  stales  that  in  liis  innsei-ies,  exposed  to  severe  fio.st  on  the 
27th  May,  18!M),  the  sjiots  whicli  carried  most  weeds  experienced  the  trrcatest 
injury. 


FROSTCRACK.  505 

in  order  to  favour  the  interchange  of  air  in  the  lower  strata  of 
the  atmosphere. 

ii.  Preserve  the  natural  soil-covering  of  dead  leaves, 
needles  and  moss. 

c.  DiiriiKj  the  UfiJIsaHon  of  Woods. 

i.  In  natural  regeneration-fellings,  the  shelterwood  should 
be  only  gradually  removed,  the  final  felling  being  delayed  till 
the  plants  have  grown  out  of  the  reach  of  late  frosts.  In 
frosty  localities,  regeneration-periods  will  be  long — from  20 
to  30  years. 

ii.  In  the  case  of  clear-cuttings,  only  small  areas  should 
be  cleared  at  one  time. 

iii.  A  protective  belt  should  be  left  intact  on  exposed 
easterly  and  north-easterly  borders  of  a  wood,  at  any  rate 
until  the  young  growth  which  it  protects  is  out  of  danger  from 
cutting  winds. 

iv.  Coppice-fellings  must  be  effected  in  the  spring;  if 
made  in  autumn,  winter-frosts  would  injure  the  stools  ;  they 
should  also  run  from  west  to  east,  so  as  to  protect  the  young 
growth  from  cold  winds ;  this  precaution  is  specially  necessary 
for  oak  coppice,  as  frozen  oak-shoots  thaw  rapidly  when 
exposed  to  the  rising  sun. 

Skction  II. — Fkostcrack. 
1.  External  Appearance. 
Frosfcrarkii  are  long  splits  caused  in  stems  by  winter-frost, 
which  start  at  the  bark  and  proceed  radially  and  more  or  less 
deeply  towards  the  centre  of  the  tree.  They  are  frequently 
followed  by  the  formation  of  projecting  longitudinal  ridges  on 
the  stem  of  an  affected  tree,  which  are  termed  frost-ribs. 

2.  Kxpla)iation. 

Frostcracks  are  due  to  the  contraction  of  the  wood  along  its 
periphery  and  radius,  owing  to  extreme  cold. 

It  has  been  proved  by  actual  measurement,  that  the 
diameters  and  girths  of  trees  of  various  species  are  lessened 
by  tbeir  loss  of  heat  during  severe  winters,  and   tbat   tliere 


506 


I'HOTKCTION    ACAINST    KKdST 


is  a  certain  ratio  l)etween  the  decree  of  frost  and  tlie  girth 
of  the  tree  (Dulianiel,  Caspar}^,  M.  Hartig,  NorcUinger, 
Vonhausen). 

The  contraction  of  tlie  wood,  the  reasons  for  which  have 
been  explained  in  the  preceding  section,  commences  at  freezing- 
point  and  increases  as  the  mercury  falls,  but  the  stem  recovers 
its  original  dimensions  during  a  thaw.  If,  therefore,  the 
temperature  but  slowly  decreases,  so  that  the  tree  becomes 
gradually  colder  from  the  exterior,  inwards,  the  volume  of  the 


Fig.  239. — Transverse  section  of  an  oak  with  two  Inotcracks.  ,t  and  f> 


bole  contracts  equably,  and  no  rupture  of  the  wood  occurs. 
For  a  tree  to  crack  there  must  be  a  rapid  fall  of  temperature, 
down  to  -18°  C.  (0'  F.).  The  external  layers  of  wood  (sapwood) 
then  freeze  to  such  a  degree  that  much  water  passes  from  the 
cell-walls  and  passes  into  the  cell-cavities.  The  central  zone 
(heartwood,  or  imperfect  heartwood)  is  either  unafU'ected  or 
much  less  affected  than  the  outer  zones  ;  it  remains,  therefore, 
either  unfrozen  or  much  less  frozen  than  the  latter.  The 
circumferential  contraction  is  therefore  chiefly  confined  to  the 
outer  zones  of  the  wood,  and  consequently  they  can  no  longer 
enclose  its  unRhrnnken  central  portion,  and  the  outer  zones 
therefore  split    radially    and    longitudinally,   the   crack    thus 


FROSTCRACK.  507 

formed  penetrating  more  or  less  deeply  towards  the  centre  of 
the  tree.  The  expansion  of  the  sap,  which  flows  into  the  crack 
and  freezes,  also  assists  in  further  splitting  the  tree  and  in 
extending  the  crack  to  the  centre. 

Most  frostcracks  occur  on  cold  nights,  between  midnight 
and  8  a.m.,  when  the  temperature  is  lowest,  and  the  contraction 
of  the  wood  is  consequently  greatest ;  the  split  is  accompanied 
by  a  noise  like  a  pistol-shot. 

3.  Daiuarje  done. 
A.  General  Nature  of  Damage. 

The  timber  of  trees  cracked  by  frost  is  of  reduced  technical 
value,  and  secondary  damage  by  insects  or  fungi  may 
supervene. 

The  extent  of  the  damage  depends  oil  the  depth  of  the 
crack,  which  varies  with  the  severity  of  the  frost. 

Frostcracks  close  again  with  the  rising  temperature,  after 
the  ice  which  has  formed  in  the  wood  has  thawed,  and  the 
sap  fills  the  cell-walls  again.  A  new  zone  of  wood  forms  over 
the  wound  ;  owing  to  the  reduced  pressure  of  the  bark,  this 
new  zone  is  broader  than  the  previous  ones.  If  tlie  cold 
continues  to  increase  the  crack  increases  in  length  and  depth. 
Frostcracks  may  attain  lengths  of  6  feet  and  more. 

In  subsequent  years  considerably  less  degrees  of  cold  in 
winter  suffice  to  open  out  the  crack  again,  as  there  is  only  the 
thin  wood  of  one  year's  zone  to  be  cracked.  It  is  closed  up 
again  during  summer.  If  this  process  be  repeated  for 
several  successive  cold  winters,  owing  to  the  successive  super- 
position of  annual  callus  growths,  a  bevel-edged  projection, 
termed  a  j'lost-rih,  is  eventually  formed,  as  shown  in  Fig.  239. 
If  there  should  be  a  succession  of  mild  winters,  a  frostcrack 
ma}'  heal  up  and  not  extend  any  further.  But  the  bark, 
which  freezes  much  less  readily,  and  is  therefore  less  liable  to 
contraction,  than  the  wood,  may  exercise  tension  on  the  latter 
and  prevent  it  from  cracking,  even  in  hard  winters.  In  such 
cases  internal  frostcrachs  result,  which  may  be  either  radial 
or  peripheral.  In  the  oak,  such  internal  frostcracks  are 
said-  to  occur  only  on  the  root-stock.     As  secondary  damage, 


508  I'ROTHCTION    AdAINST    FROST. 

attacks    by   insects    and    fungi    {Xectria    and    Polijponis  sp.) 
may  frequently  ensue. 

B.  Damage  done  in  Particular  Cases. 

(a)  Sjyccies. — Hardwoods  with  large,  medullary  raj's  are 
most  subject  to  frostcrack.  Deep  roots  also  favour  it,  as  they 
pass  into  zones  of  soil  which  are  only  slightly  affected  by  the 
air  temperature  and  thus  keep  the  stem  comparatively  warm. 
This  difference  of  temperature  between  the  outer  and  inner 
zones  of  the  wood  of  a  tree  increases  its  liability  to  crack. 

Oak,  beech,  walnut,  elm,  ash  and  sweet  chestnut  are  the 
trees  most  subject  to  frostcrack,  and  Turkey  and  sessile  oaks 
more  than  pedunculate  oak.  The  sap,  which  pours  from  the 
wound  after  a  thaw,  turns  dark  brown  and  betrays  the  injury 
which  the  tree  has  received. 

Frostcracks  also  occur  in  the  ease  of  softwoods,  sucli  as  the 
horse-chestnut,  lime,  poplars,  and  tree-willows.  They  are 
rare  on  conifers,  and  then  chiefly  on  the  silver-fir. 

(b)  Part  of  Tree. — Frostcracks  usually  occur  in  the  lower 
part  of  the  stem  of  a  tree,  especially  at  places  where  tlie  growth 
is  uneven  near  the  root-stock,  at  knots,  or  where  the  stem  is 
eccentric. 

Splitting  is  furthered  by  local  w'ounds  owing  to  the  admission 
and  freezing  of  sap,  and  is  verj' common  in  the  case  of  coppice- 
shoots  which  have  been  allowed  to  grow  into  trees,  and  wliicli 
are  always  unsound  at  their  base.  Splits  Irom  the  root-stock 
proceed  upwards  and  from  a  knot  downwards ;  on  eccentric 
stems,  they  are  always  towards  the  largest  diameter. 

In  the  case  of  stems  of  a  regular  shape,  the  south  side 
suffers  most  from  frostcrack,  and  then  the  east  and  north 
sides,  the  westerly  side  suffering  least  of  all.  The  south  side 
suffers  most,  because  themost  vigorous  circumferential  growth 
takes  place  there,  and  the  tissues  are  consequently  very 
sappy. 

{(■)  Si/stciiis  of  Management. — Standards  over  coppice  suffer 
most,  as  the}'  are  exposed  to  cold  winds,  whenever  the  under- 
wood is  felled.  Standards  in  high  forest,  which  are  exposed 
after  growing  in  a  dense  wood,  are  also  very  liable  to  frost- 
crack. 


FROSTCRACK.  5U9 

In  the  Kottenforst,  near  Bonn,  an  area  of  7,400  acres 
at  an  altitude  of  426  feet,  where  the  treatment  is  that 
of  coppice-with-standards,  and  the  soil,  clay  with  an  imper- 
meahle  suhstratum,  over  twenty  per  cent,  of  the  oak  stan- 
dards are  frostcracked.  Frostcrack  is  also  very  prevalent  in 
the  seventy  to  eighty-year-old  oak-woods  in  Windsor  Forest, 
owing  to  the  ahsence  of  underwood,  and  it  is  also  extremely 
common  in  the  open  parts  of  the  Forest  of  Dean,  where  the 
underwood  has  heen  hrowsed  down  by  sheep. 

(d)  Age  of  Tree. — Large  old  trees,  as  a  rule,  suffer  more 
from  frostcrack  than  younger  trees,  because  the  differences  in 
temperature  between  their  outer  and  inner  woody  zones  are 
greater. 

(e)  Locality. — Fertile  and  moist  soils  favour  frostcrack.  It 
is  very  frequent  in  narrow  valleys  along  watercourses,  where 
the  night  temperature  falls  exceptionally  low  in  winter. 

(/)  Season. — Frostcracks  generally  occur  late  in  the  winter, 
when  the  sap  begins  to  flow,  provided  intense  cold  should 
set  in.  The  sajjwood  then  rapidly  cools  and  contracts,  while 
the  inner  zones  of  tl)e  wood  retain  a  higher  temperature  and 
do  not  contract.  Long-protracted  and  gradually  falling 
temperatures  are  not  so  dangerous.  Storms  increase  the 
danger  by  blowing  the  frozen  stems  backwards  and  forwards  ; 
Hess  even  considers  it  probable  that  storms  may  occasion 
frostcracks  at  the  commencement  of  a  thaw,  but  as  the  outer 
zones  of  the  wood  would  then  be  expanding,  whilst  the  inner 
zones  remain  cold,  a  cup-shake,  or  separation  of  the  wood 
along  a  portion  of  tiie  whole  of  an  annual  ring,  would  probably 
result. 

4.  Protective  Rules. 

i.  Thoroughly  drain  wet  soils. 

ii.  Keep  up  the  density  of  woods,  and  underi)lant  all 
pure  oak  high  forests  with  a  shade-bearer,  such  as  beech  or 
silver-fir. 

iii.  Establish  protective  belts  of  spruce  along  the  north- 
eastern, eastern,  and  south-eastern  boundaries  of  a  wood. 

iv.  Abandon  the  practice  of  reserving  oak  and  other 
standards  in  places  where  frostcrack  is  common. 


510  IMIO'IKCTION    ACAIXST    FROST. 

Section  III.-  -Frost-Canker. 

Cankers  may  be  caused  by  frost  among  young  broadleaved 
species,  such  as  oaks,  ash,  maples,  beech,  fruit-trees,  etc., 
which  have  not  yet  grown  above  the  local  frost-level.  Thus, 
at  the  base  of  a  young  s'loot,  which  has  been  repeatedly  frozen 
down  to  the  main  stem,  the  living  bark  separates  from  the  dead 
wood.  A  callus  forms  round  the  wood  in  the  growing  seasoif, 
but  is  frozen  on  the  recurrence  of  severe  frost,  and  as,  in 
frost-hollows,  this  may  happen  annually,  a  canker  is  thus 
formed,  and  the  wood  may  be  killed  down  to  the  pith,  on  the 
side  from  which  the  branch  arose.  These  cankers  are  formed 
near  the  root-stock  of  oaks  and  ash  growing  in  depressions  on 
stiff  clay  soil ;  they  may  be  distinguished  from  others  caused 
by  fungi,  as  they  increase  in  size  only  after  severe  frost. 

Frost-cankers  on  Shorca  rohusta  are  very  common  in  frosty, 
depressions  in  Northern  India,  the  shoots  being  killed  down 
to  the  ground  annually  until  an  abnormally  large  flattened 
stool  is  formed.  Coppice-shoots  of  a  variety  of  sweet  chestnut 
from  the  south  of  France  are  also  similarly  frozen  down  in 
Alsace,  while  the  common  variety  of  the  tree  produces  splendid 
coppice-poles. 

Section  IV. — Uprootinct  of  Seedlings  pa-  Frost. 
1.  General  Accoiiiit. 

During  Feln-uary  and  March,  when  night-frosts  alternate  with 
thaws  in  the  day-time,  it  is  often  found  that  young  seedlings 
are  raised  with  the  soil,  and  in  the  subsequent  thaw,  when  the 
soil  sinks  back  again,  their  roots  lose  their  held  on  the  ground, 
and  the  plants  fall  over  and  die.  This  action  is  termed yVos^ 
liftinp,  the  seedlings  being  lifted  by  the  alternate  frost  and  thaw. 

In  such  cases  the  surface-soil  is  raised  by  the  conversion  of 
the  water  in  it  to  ice-crystals,  and  the  little  seedlings  are  thus 
lifted  above  their  original  position.  "When  the  thaw  sets  in, 
and  the  soil  gradually  softens  and  returns  to  its  original  level, 
the  plants  cannot  do  so,  as  their  roots  are  in  the  deeper  and 
still  frozen  soil,  while  the  surface-soil  is  thawing ;  when,  there- 
fore, the  soil  has  completely  thawed,. the  plants  lose  their 
root-hold  and  fall  over,  as  shown  in  Fig.  240.     Even  when  the 


UPROOTIN<;    TiY    FROST. 


511 


soil  is  thawed  completely,   the  plants  cannot  resume  their 
original  position,  their  roots  not  being  stiff  enougli. 


FiiT.  210. — Spruce  bt-udliug  (a)  lifted  (b),  (<)  iiuil  {(/)  and  uprooted  by  frost  {e). 
(X)  Original  grouud-level. 

2.  Dainaffc  done  in  Particular  Cases, 
(a)  Species  and  Age  of  Pla)it. — Nearly  all  woody  plants  may 
be  uprooted  l)y  frost  during  the  lirst  two  years  of  their  life, 


512  I'RO'I'ECTION    ACAINST    FROST. 

and  especially  those  of  shallow-rooted  species,  such  as  spruce, 
birch,  alder,  beech,  hornbeam,  etc.  Even  ash,  sycamore,  and 
silver-lir  are  not  unfreqnently  uprooted  in  this  way.  Sweet 
chestnut,  hazel  and  oaks  escape  this  form  of  injury  on  account 
of  the  depth  to  which  their  tap-root  descends  during  germina- 
tion. The  greatest  damage  is  done  in  nurseries  to  seed-beds 
and  beds  of  transplants,  and  to  sown  areas  in  forests. 

{b)  Locality. — Certain  soils  and  localities  suffer  more  than 
others  in  this  way.  Thus,  provided  they  are  moist — line 
soila,  such  as  peat,  fine  sand,  marls  and  loam,  are  most 
exposed  to  frost-lifting.  Dry  sandy  soils  do  not  sufit'er.  As  a 
rule,  the  finer-grained  a  soil  is,  the  more  water  it  absorbs, 
and  plants  are  therefore  more  easily  lifted  in  such  soils, 
whilst  in  coarse-grained,  sandy  soil  the  water  descends,  and 
the  surface  is  therefore  not  subject  to  lifting.  Soil  bare  of 
herbage  is  also  more  easily  lifted  than  soil  which  is  kept  down 
by  the  roots  of  grass  and  weeds. 

As  regards  locality,  deep  depressions  suffer  most,  as  there 
is  then  less  chance  of  the  moisture  draining  away.  Warm 
aspects,  except  westerly  ones,  suffer  most,  as,  on  them,  thaw- 
ing and  freezing  follow  one  another  most  frequently ;  northerly 
aspects  hardly  suffer  at  all  from  frost-lifting. 

3.  Protective  Bides. 

(a)  For  the  Forest. — Drain  away  all  superfluous  moisture 
by  open  drains ;  drain -pipes  may  be  used  only  in  nurseries. 
Planting  should  be  preferred  .to  sowing,  and  ball-planting  is 
the  best  security  against  this  evil,  while  spring-plantings 
suffer  less  than  autumn-plantings.  Where  sowings  are 
adopted,  oajis  may  be  mixed  with  the  seed,  which  should  be 
sown  rather  densely.  Preserve  the  natural  soil-covering  of 
weeds  when  plantations  are  made  on  soil  liable  to  be  lifted' 
by  frost. 

{b)  For  Forest  Nurseries. — Mix  clay  soils  with  25  to  33  per 
cent,  of  sand,  liaise  the  seed-beds  so  as  to  secure  good  drain- 
age. Sow  deeply  and  densely,  and  cover  the  spaces  between 
the  drills  or  rows  of  plants  with  straw,  dead  leaves  or  saw- 
dust, all  of  which  are  bad  conductors  of  heat ;  even  cinder- 
dirt  mixed  with  sand  may  be  used  ;  this  delays  thaws.     After 


UPROOTING    BY    FROST. 


513 


weeding  between   the  rows  of  plants,  fill  with  good  soil   all 
inequalities  thus  produced  in  the  beds. 

It  is  advisable  in  autumn  to  leave  a  few  weeds  in  the  beds, 
as  their  rojts  give  coherence  to  the  soil.  Any  plants  which 
have  been  uprooted  by  frost,  should  be  at  once  replaced,  and 
fine  soil  placed  round  them.  This  is  not  an  expensive  opera- 
tion if  boys  are  employed,  and  costs  only  from  threepence  to 
fourpence  per  thousand  plants. 


Fig.  241.— Effects  of  Wiud  on  Beech.     Altitude 
Photo,  by  R.  E.  Marsden. 


2,500  ft. 


F.P. 


LL 


514 

CHAPTER   11. 

PEOTECTION    AGAINST    INSOLATION. 

Insolation  may  dni  up  seeds  and  yoiiiif,'  plants,  or  twigs  and 
branches  of  trees  ;  it  may  also  san-ch  or  crack  the  hark  and 
wood  of  trees. 

Section  I. — Drought. 
1.  Ajipcarancc  and  Cause  of  Injury. 

A  period  of  more  than  14  consecutive  days  without  rain  is 
termed  "absolute  drought";  a  "partial  drought"  is  when 
for  28  days  the  average  daily  rainfall  is  not  more  than 
one-hundredth  part  of  an  inch.* 

Woody  plants,  and  parts  of  them  which  have  been  dried  by 
the  sun,  have  much  the  same  appearance  as  if  they  had  been 
killed  by  frost ;  blossoms,  leaves,  needles  and  young  shoots 
^rst  wait,  then  gradually  turn  brown  and  shrivel  up  ;  they 
finally  fall  off,  although  dried  leaves  may  remain  for  a  long 
time  hanging  on  the  trees. 

This  drying-up  of  leaves  and  shoots  is  the  result  of  pro- 
longed hot,  dry  w^eather,  which  abstracts  much  moisture  from 
plants  and  from  the  soil ;  transpiration  being  thus  greatly 
increased,  plants  pass  oflf  more  watery  vapour  into  the  air 
than  their  roots  oan  absorb  from  the  soil,  which,  becoming 
continually  drier,  is  less  able  to  meet  their  demands.  The 
action  of  heat  on  forest  plants  is  therefore  indirect,  as  the  sun's 
rays  do  not  kill  them  directly. 

2.    l>(iiii(i<ii'  done. 

•  A.   General    Account. 

Owing  to  the  want  of  the  necessary  moisture  in  the  soil 
usually  caused  by  high  degrees  of  heat,  seeds  may  not  secure 
Hufiicient  water  for  germination,  and  young  seedlings  may 
be  killed.  In  the  case  of  older  plants  the  foliage  dries  up  and 
falls  prematurely,  the  younger  shoots  may  be  killed,  and  the 
annual  wood-increment  considerably  reduced. 

Drought  at  the  commencement  of  the  growing  season  reduces 

*  "British  llainfaU"  (Kd.  Stanton!,  J.oiig  Acre,  \\m\). 


DROUGHT. 


515 


the  height-growth  (1893)  ;  at  its  close,  it  reduces  radial  growth 
(1887).  Dry  years,  as  well  as  frost  years,  may  be  detected  on 
the  transverse  sections  of  a  bole  by  narrow  annual  zones. 

Professor  Henry,*  of  Nancy,  measured  250  trees  in  order  to 
ascertain  the  loss  of  diameter  increment,  in  the  very  dry 
summer  of  1893,  with  the  following  result : — 


Reduction  of  diameter  in  the  yeai-s  — 

Species. 

Soil. 

1 

1891. 

1892. 

1893. 

1 

Per- 

Per- 

From 

To 

centage. 

To 

centage. 

Oak 

!  Loam         

100 

83 

17 

77 

23 

Calcareous 

100 

91 

9 

75 

25 

Beech 

Doep  clav 

100 

77 

23 

41 

59 

., 

Shallow  calcareous 

100 

56 

U 

30 

70   ■ 

Hornbeam  .. 

1                  - 

100 

86 

14 

49 

51 

Spruce 

1 

100 

77 

23 

44 

56 

Occasionally  single  stenls,  or  groups  of  poles,  may  be 
killed  by  insolation ;  this  is  frequently  the  case  with  beech 
standards,  which  after  growing  in  a  dense  wood  are  exposed, 
as  mother-trees,  in  seeding-fellings.  The  yield  of  dead  wood 
in  dry  years  is  very  considerable. 

In  seasons  of  drought  plants  cannot  obtain  sufficient  nitrogen 
compounds  from  the  soil;  E.  Mer  also  proved  that  starch- 
production  in  the  leaves  is  weakened.  PFants  by  premature 
leaf-fall  also  suffer  a  considerable  loss  of  combined  nitrogen  and 
phosphoric  acid,  that  prejudices  the  formation  of  fruit  and  seed. 

Professor  Krausf  analysed  the  leaves  of  lilac,  Comns  mas, 
L.,  and  horse-chestnut  with  the  following  results : — 


Chemicals. 

Dead  Leave.s 

in  Summer. 

Autumn 

Leaves. 

Percentage. 

Percentage. 

N 

1,947 

24 

1,370 

14 

P.2  05 

.-.22 

6-5 

373 

3-8 

K.,0 

2,9'.tS 

37-3 

3,831 

39-7 

CaUo 

1,,S7S 

— 

2,4 1 6 

— 

Other  mineral  matter 

8.028 

'.i.f;:5(; 

— 

•  "  Rev.  (les  E.  et  F.,"  1895,  p.  75. 
t  "  Die  Sommerdiirre  der  Baiime," 
wesen,"  1875,  p.  206. 


'Central   Hlatt  fiir  das  (Je.sammte  Forst- 


L  L 


516  PROTKC'J'ION    AGAINST   INSOLATION. 

Thus,  nitrogen  and  phosphoric  acid  are  only  about  half  as 
bulky  in  autumn  leaves  as  m  summer-dried  leaves,  potash 
being  nearly  equal  in  both,  while  lime  and  other  mineral 
matter  is  greater  in  the  autumn  leaves. 

Similar  figures  hold  good  for  the  leaves  of  other  forest 
trees,  and  it  is  therefore  evident  that  nitrogenous  matter  and 
phosphoric  acid  i)ass  back  in  the  autumn  from  the  leaves 
into  the  twigs,  and  that  if  the  foliage  sliould  fall  prematurely, 
the  trees  must  lose  a  quantity  of  these  valuable  substances. 

Other  secondary  dangers  caused  by  drought  are  a  greater 
liability  of  trees  to  insect-attacks,  and  increased  danger  from 
forest  fires. 

B.  Damage  under  Special   Conditions. 

(a)  Species. — The  relative  susceptiliility  of  trees  when  very 

young  to  be  injured  by  insolation  is  shown  in  the  following 

groups  : — 

i.  Veky  Susceptible  Species. 

Beech,  ash,  sweet-chestnut,  black  alder;  silver-fir,  spruce. 

ii.  Susceptible  Species. 
Hornbeam,  sycamore,  Norway  maple,  limes  ;  white  alder, 
birch  ;  Cembran  pine,  larch. 

iii.   Hap.dy  Spkcies. 

Oaks,  elms,  field-maple,  horse-chestnut,  robinia,  planes, 
Pyrus  spp.,  wild  cherry,  poplars,  willows  ;  Scots,  Austrian, 
Weymouth  and  mountain  pines,  and  juniper.* 

The  drought  of  the  year  1893,  according  to  Mer,  caused 
the  silver-fir  in  the  Vosges  Mountains  to  produce  only  f — |  of 
its  normal  diameter-increment  and  \ — f  of  the  normal  length- 
increment. 

(b)  A(/e  of  Tree. — Sowings  and  i)lantings  in  the  open  are 
most  exposed  to  damage  during  the  early  years  of  their  life, 
until  they  have  completely  covered  the  ground.  On  poor, 
shallow  soils,  and  in  hot  places,  without  lateral  shelter,  i)lants 
aged  up  to  twelve  or  fifteen  years  may  die  from  drought.  It 
has  been  observed  that  older  transplants  on  w'eedy  ground 
suffer  more  from  (lroi>glit  than  younger  transplants  on  fresh 

*  Austrian  pine  lias  provod  very  successful  for  (tlivnting  dry  calcareous  rock 
Hi  Hochefort,  in  Beigium. 


DROUGHT.  517 

clearings,  as  in  the  latter  case  dew  and  rain  have  more  access 
to  the  soil.  When  once  a  planTiation  has  closed  in,  so  as  to 
cover  the  soil  completely,  the  chief  danger  from  drought  is 
over;  but  occasionally  spruce  poles  have  been  killed  by 
prolonged  drought, 

(c)  Locality. — In  plains  and  hilly  lands,  the  danger  from 
drought  is  greater  than  in  mountains  where  the  most 
extensive  forests  are  found,  as  then  damper  air,  more 
frequent  precipitations  and  raoister  soil  prevail.  Eegions 
over  1,500—1,800  feet  altitude  have  little  to  fear  from  drought. 
Small  flat  hills  and  narrow  ridges  suffer  most  of  all. 

As  regards  aspect,  the  southern  and  south-western  slopes 
suffer  most  from  drought,  and  the  northern  slopes  least  of 
all.  Ill  very  narrow  valleys  which  have  been  cleared  of 
trees,  or  are  scantily  wooded,  the  reflection  of  the  heat  from 
side  to  side  greatly  increases  its  eflects,  and  rows  of  houses 
have  the  same  eft'ect  on  street-avenues. 

As  regards  soils,  woods  growing  on  calcareous  soils,  and 
especially  on  stony  superficial  soils  above  calcareous  rocks, 
sufler  most  from  heat ;  then  those  on  stiff  clays,  whilst  sandy 
soils  are  more  favourable  as  regards  drought,  especially  when 
the  grains  of  sand  are  fine ;  woods  on  sandy  loams  and  loams 
stand  drought  best  of  all.  This  is  due  to  the  following 
causes  :  poor  shallow  calcareous  soil  is  not  retentive  of 
moisture,  while  the  porous  rock  beneath  it  drains  away  water 
rapidly  from  the  surface ;  marls  and  clays  become  hard  when 
exposed  t5  heat  and  crack  in  all  directions ;  coarse  sands 
suffer  more  than  fine  sands  on  account  of  the  greater  capil- 
larity of  the  latter,  which  attracts  water  from  below ;  loams 
readily  al^sorb  rain,  dew  and  snow-water,  and  retain  moisture 
in  the  subsoil,  and  can,  therefore,  easily  replace  the  loss  of 
the  surface-water. 

{d)  Soil-covering. — Weeds,  and  especially  a  dense  tall  growth 
of  grass,  increase  the  dangers  of  drought,  filling  the  soil  with 
their  roots  and  absorbing  and  transpiring  its  moisture,  which 
would  otherwise  be  available  for  the  woody  plants  growing  in 
or  above  the  grass.  A  light  covering  of  isolated  shrubs,  on  the 
contrary,  may  prove  beneficial  by  shading  the  valuable  species. 

Leaves    and    moss  and    the    humus    resultinji    ivoni    tiieir 


518 


PROTECTION    AOAINST    INSOLATION. 


decomposition  on  the  surface  of  the  ground  shelter  the  roots 
of  trees  from  the  sun. 

(e)  Density  of  Crop. — Woods  in  which  tlie  trees  stand  some- 
what far  apart  from  one  another  suffer  more  from  drought 
than  well-stocked  woods.  Isolated,  clean-boled  standards 
with  smooth  bark,  such  as  beech,  hornbeam,  birch,  silver-lir, 
especially  at  noon,  reflect  the  rays  of  the  sun  on  to  the  soil, 
as  shown  in  Fig.  242,  and  thus  dry  up  the  soil  around  them ; 

young  natural  -  regeneration 
may  fail  completely  around 
such  trees. 

(/)  Weatlicr  and  Season  of  the 
Year. — The  drying-up  of  little 
plants  owing  to  drought  may 
be  recognisable  early  in  the 
summer.  A  dry  May  with  a 
continuance  of  cutting  east 
winds  soon  disperses  the 
moisture  in  the  soil  that  has 
accumulated  during  winter,  and 
if  there  is  insufficient  rain 
in  June,  many  plants  on  areas 
recently  sown  or  planted  may 
be  killed.  If  tlie  dry  weather 
should  continue  throughout 
July,  more  damage  will  be 
done,  and  it  is  generally  from 
the  middle  of  July  till  the 
plants  die,  for  the  maximum 
summer  -  temperature  is  attained  at  about  a  month  after 
Midsummer-Day. 

Not  until  the  beginning  of  September,  therefore,  can  young 
plantations  and  sowings  which  have  hitherto  escaped  be 
considered  out  of  danger  from  drouKht. 


middle    of    August    that    the 


3.   Jief/isler  of  l)ri/    ]'((irs. 
Dui'ing  the  past  century,  the  following  have  been  years  of 
drought  in  Central  Europe  :  1800, 1807,  1811,  1812, 1822, 1834 
1812,  1840,   1857,   1858,  1851),  18(33,  1805,   1808,   1874,   187(), 


DROUGHT. 


519 


1881,  1883,  1889,  1893,  1898  and  1906  (autumn)  ;  or,  on 
the  average,  one  year  in  five.  To  give  a  local  example,  the 
monthly  rainfall  and  maximum  temperature  observed  in 
1893,  at  Coopers  Hill  College,  Surrey,  are  here  given. 


Months. 

Uainfall  in 
Inches. 

AvKKAGE  Max. 

Tempekatuuk 

IN  Dborees  Faur. 

Remarks. 

1803. 

Aver- 
ages 
1875-92. 

Diffe- 
rences. 

1893. 

Aver- 
agfis 
1875-92. 

Diffe- 
rences. 

Jaiiuaiy  ... 
l"Y'bru;uv... 
Mar.-l.  .:.... 

Al)iil     

Mnv 

1-21» 

:{U7 

•12 
•7(5 

214 

1  ■:{.-, 

1  Ol 
(i-lO 
1-S4 
300 

1-98 
1-70 

ir.2 

1-77 
1-92 
2-22 
2-72 

2-:}8 

2-2() 
*2-(il 
2-54 
2-01 

-  -69 
+  1-37 
-1-14 
-1«.5 
-11(5 
-1-47 

-  -.58 
-1-03 

-  1-25 
+  3-4!» 

-  •7(» 

+  -yy 

r,.-)-4 
(>:{■() 
6(;-4 

7H(j 
fi7-4 
72-4 
()8-l 

47-1 
.53-2 

r.y-8 
(;6-3 

68-7 

68-8* 

(J4 

+  8-8 
+  10-4 
-f   (i-C, 
+   7-8 

-  1:5 
-f  .•5-(; 
+  4-1 

■8  in.  of  the  March  rainfall 
fell  on  the  fii-st  r>  days  of 
the  month,  about  •.'>  in.  fell 
on  the  12tiiJuly,and2-.5in. 
on  the  10th  October. 

The  temperature  was 
above  80°  F.  on  the  21st 
April,  on  4  days  in  June,  5 
(hiys  in  July,  8  days  in 
August,  and  once  in  Sep- 
tember, themaxinium  being 
91-8°,  on  the  lyth  August, 

.lulv 

Au.uMist 

Scptciiibor.. 
October    ... 
NDvenilicr.. 
PecembLM- .. 

Totals  ... 

21-81 

2:)a;8 

-  3-8i 

*  For 

17  years  only. 

All  farms  on  the  shallow  soil  above  the  chalk  suffered  greatly 
from  drought,  and  there  was  scarcely  any  hay,  and  corn  was 
very  short  in  stalk.  As  regards  tlie  effects  on  forest  growth, 
there  was  an  enormous  crop  of  acorns  and  sweet-chestnuts.  All 
the  lime  blossom  fell  without  maturing  fruit,  and  isolated 
beech,  elm  and  lime-trees  lost  most  of  their  foliage  in  August. 
Tli^  heavy  fall  of  rain  in  February  and  the  first  few  days  of 
March  soaked  the  ground  so  thoroughly,  that  a  plantation  of 
twenty  acres  of  three-year-old  Scots  pine  transplants  on  the 
Bagshot  sands,  in  Windsor  Forest,  w^as  a  complete  success,  in 
spite  of  the  drought. 

4.  Protective  Rules. 

a.   iHuiiuj  Die  Formafmi  of  Woods. 

i.  Natural  reproduction  is  preferable  to  artificial  sowing,  or  if 

it  cannot  be  carried  out,  choose  deep-rooted  strong  transplants 

and   cover   the   planting   spots   with    sods    or    large   stones. 

Nursery    Iransplunts,   when  planted  out   in  the  forest,  st.ind 


52U  PROTEC'IION    AOAINST   INSOLATION. 

drouglit  better  than  seedlings  taken  directly  from  the  seed-beds. 
Coniferous  plants  taken  from  the  nursery  with  balls  of  earth 
round  their  roots,  stand  drought  less  well  than  strong  well- 
rooted  transplants  ;  mound-planting  also  gives  bad  results  in 
very  dry  years,  and  it  may  then  be  necessary  to  plant  out  spruce 
only  under  shelter  of  birch  or  Scots  pine  nurses. 

ii.  The  soil  should  be  deeply  trenched,  and  sowing,  or 
planting  of  yearlings,  should  be  carried  out  simultaneously 
with  the  growth  of  a  crop  of  oats,  or  buckwheat,  which  will 
shelter  the  young  plants  till  the  autumn  ;  the  deeply  trenched 
soil  enables  Scots  pine-seedlings  to  form  deep  roots,  arnd  soil 
which  has  been  well  worked  parts  with  moisture  less  freely, 
and  is  more  hygroscopic  than  a  compact  soil.  In  years  of 
drought  and  on  poor  dry  soils,  moss  should  be  placed  between 
the  lines  of  sowings  ;  this  costs  about  £1  an  acre. 

iii.  In  hot  countries,  planting  should  be  done  at  the  very 
commencement  of  the  monsoon,  and  sowing  is  often  preferable, 
as  many  plants,  such  as  teak,  form  very  long  tap-roots  imme- 
diately after  germination.  Planting  may  also  be  done  by 
means  of  plants  grown  in  small  bamboo-baskets,  which  soon 
rot  and  allow  the  roots  to  spread  in  the  soil. 

b.   EiiJes  for  Ni/rsen'm. 

i.  Subdivide  the  area  of  the  nursery  by  narrow  evergreen 
hedges,  or  provide  temporary  side  shelter  by  mats  ;  these 
precautions  ai-e  especially  necessary  for  spruce. 

ii.  Trench  the  nursery-beds  deeply  in  autumn,  and  manure 
with  compost,  or  burned  sods ;  this  not  only  keeps  the  l^ds 
free  from  weeds,  but  also  promotes  the  development  of  strong 
fibrous  roots. 

iii.  Transplant  yearling  plants,  especially  of  spruce,  into 
nursery-lines. 

iv.  Nursery-beds  of  seedlings  may  be  temporarily  protected 
by  sticking  branches  into  the  ground  on  the  south  side  of  the 
beds  or  all  round  them,  or  by  covering  them  with  mats, 
supported  by  a  framework,  4  to  6  feet  high,  as  in  protecting 
plants  against  frost.  The  mats  may  be  removed  during 
showers,  and  only  placed  over  the  beds  at  tlie  hottest  time  of 
day,    from   11  a.m.   to  8  p.m.      Such  shelter  should  also    be 


DROUGHT.  521 

withdrawn  in  the  autumn  in  order  to  harden  the  plants.  "Where 
branches  are  used  to  protect  plants  from  the  sun,  Scots  or 
Weymouth  pines  are  preferable,  as  broadleaved  branches  soon 
have  their  foliage  shrivelled,  and  spruce  needles  fall  off,  while 
silver-fir  foliage  is  too  dense. 

(v.)  Keep  the  beds  free  from  weeds,  as  weeding  prevents  the 
soil  from  caking,  and  renders  it  hygroscopic  ;  for  this  purpose 
the  spaces  between  the  plants  should  be  hoed  in  hot  summers, 
even  if  there  are  no  weeds.  Soft  earth  may  be  placed  on  either 
side  of  the  rows  of  plants,  w4ien  the  beds  are  weeded. 

vi.  The  plants  may  be  watered,  or  irrigated  ;  it  is  best  to 
water  in  the  evening,  and  when  watering  has  been  commenced 
it  must  be  repeated  from  time  to  time  till  rain  falls,  as  it 
encourages  the  formation  of  superficial  rootlets,  which  would 
soon  die  should  the  beds  become  too  dry.  On  this  account  the 
beds  should  be  watered  only  when  absolutely  necessary.  The 
crust  of  earth  on  the  surface  of  the  beds,  due  to  watering,  must 
from  time  to  time  be  broken  up  with  the  hoe.  An  account 
of  nursery-irrigation  is  given  in  Schlich's  Silviculture.* 

c.  Rules  for  Tending  Wvods. 
All  epicormic  branches  must  be  pruned  from  standards 
reserved  in  high  forest,  or  over  coppice,  as  they  keep  rain  and 
dew  from  the  young  plants,  and  render  the  standards  stag- 
headed.  The  standing-crop  should  be  kept  as  dense  as  possible, 
and  the  natural  soil-covering  preserved.  Trees  along  the 
boundaries  of  a  forest,  or  along  roads,  should  be  kept  dense, 
and  the  outer  row  be  allowed  to  branch  down  to  the  ground, 
so  AS  to  exclude  dry  hot  winds  from  the  forest.  A  series  of 
horizontal  trenches  may  be  dug  along  dry  slopes,  in  order  to 
retain  the  rain-water. 

(I.  Rules  during  Utilimtion  of  Woods. 

The  seeding-cuttings  on  poor  dry  soils  should  be  kept  dark, 
but  at  the  same  time,  after  a  good  crop  of  seedlings  has  sprung 
up,  the  plants  should  be  rapidly  or  gradually  exposed  according 
to  their  demands  on  light  so  that  they  may  get  the  full  benefit 
of  rain  and  dew,  and  develop  rapidly.  All  isolated  smooth 
barked  mother-trees  should  be  felled,  and  the  bare  patches 

*  '•  Manual  of  Foiestry  '  (3icl  edition),  Vol.  II.,  \>.  137. 


522 


PROTECTION    AGAINST    INSOLATION. 


round  their  stumps  planted  up.  Small  narrow  felling-areas 
should  be  established,  running  from  north-west  to  south-east, 
as  far  as  this  can  be  done  without  danger  from  storms,  so  that 
the  young  crops  may  get  lateral  slielter  from  the  old  wood  to 
the  south-west  of  them. 

Section  II. — Baek- Scorching. 
1.  External   Appearance. 
Tiie  name  harlt-scorcJiing*  denotes  a  well-known  niaiad}'  of 
trees,  which  generally  occurs  on  the  western  or  south-western 


Fiji;.  243. — Transverse  section  ol  ^  bctcli  ali'cctcd  by  bark-scorching',  cut  12  feet 
above  tlie  »round.     The  damage  is  limited  to  tlie  sector  a  b  c. 

sides  of  stems  and  in  directions  intermediate  to  them,  the 
W.S.W.  side  being  the  commonest  seat  of  injury,  while  it  only 
exceptionally  happens  on  the  southern  side  of  a  tree.  This 
injury  is  first  rendered  visible  by  the  drying  up  of  the  l)arkof 
affected    trees,    which    assumes    a    reddish  colour,   and  then 

•  The  term  burk-xcorchiM/  is  used  in  Somerville's  translatidii  of  llartig's 
Disea.scs  of  Trees,  and  is  a  better  term  tiian  hn rJi-lilisli-r.  wliidi  has  alnady 
been  ai)|dlcd  to  dise;uses  caused  ijy  fungi. 


BARK-SCORCHING.  523 

gradually  splits  lengthwise  and  horizontally  from  the  stem,  and 
falls  off  in  pieces.  Tlie  injured  sapwood  turns  brown,  the 
brown  colour  fading  gradually  towards  the  still  sound  wood. 

The  exposed  wood  becomes  rotten  owing  to  the  admission  and 
germination  of  spores  of  various  species  of  Polyiwrus.  By 
strong  and  repeated  insolation,  the  rot  spreads  in  a  wedge- 
shaped  manner  down  into  the  heart  of  the  tree  in  the  direction 
of  the  medullary  rays  (Fig.  243). 

The  destructiveness  of  the  fungi  is  frequently  hastened  by 
the  fact  that  a  strong  growth  of  grass  and  herbage  dries  up 
the  surface  moisture  of  the  soil. 

2.  Explanation. 

Bark-scorching  is  the  result  of  powerful  insolation.  If  the 
sun  beats  directly  on  a  stem,  its  west  and  south-west  sides 
become  considerably  heated.  The  southern  side  of  a  tree  is 
less  heated  owing  to  the  frequent  easterly  winds,  which  blow 
during  hot  anticyclones  when  the  sky  is  clear,  and  skim  past 
the  southern  side  of  trees,  and  reduce  the  temperature  of  their 
bark  and  sapwood  on  that  side,  whilst  the  W.S.W.  side  of  the 
tree  is  not  affected  by  the  east  wind.  This  explanation  is 
confirmed  by  the  fact,  that  when  the  southern  side  of  a  tree 
is  scorched,  it  has  been  found  to  be  sheltered  from  easterly 
winds  by  an  adjoining  dense  wood.  The  greater  effects  of  the 
sun's  rays  on  the  W.S.W.  side  of  a  tree  are  also  due  to  the  fact 
that  the  maximum  daily  temperature  is  in  the  afternoon,  when 
the  sun  has  passed  the  meridian,  and  that  the  lower  the  sun 
is,  the  more  direct  are  its  rays  in  the  radial  direction  of  the 
stem,  and  the  more  intense  are  their  effects. 

Vonhausen  found  that  the  maximum  temperature  on  the 
^V.S.^^'.  side  of  a  tree,  between  its  bark  and  sapwood,  was 
120"  F.  when  the  air-temperature  was  91°  F.,  while  in 
Bavaria,  on  the  18th  August,  1892,  with  an  air-temperature 
of  96'8°  F.,  Hartig  observed  a  temperature  of  131^  F. 
between  the  bark  and  sapwood  of  some  isolated  80-year-old 
spruce  trees.  Cambium  cells  of  European  trees  cannot  with- 
stand temperatures  between  104" — 130°  F.  any  better  than 
leaves  and  herbaceous  shoots,  which  are  speedily  killed  by 
such  temperatures. 


524  PROTEC'llON    AGAINST    INSOLATION. 

3.  Dantafic  done. 

(a)  In  (leueral. — This  malady  reduces  the  technical  value  of 
the  stems  and  frequently  kills  a  tree.  The  forest-owner  thus 
suffers  a  loss  of  timber  and  increment,  to  which  may  be  added 
danger  of  breakage  and  of  insect-attacks,  and  exposure  of 
young  growth  requiring  shelter. 

{h)  Species. — Bark-scorching  affects  chiefly  trees  with  thin 
and  persistent  smooth  cortext,  free  from  cracks. 

Species  of  trees  that  produce  thick  bark,  and  the  bark  of 
wliich  is  rough  and  fissured,  do  not  suffer.  Their  dead  coarse 
bark  is  a  bad  conductor  of  heat,  and  never  becomes  heated  to 
the  same  extent  as  smooth  bark.*  The  bast  under  coarse  bark 
offers  a  further  protection  to  the  cambium  against  insolation. 

Beech  suffers  most,  then  spruce  and  Weymouth  pine. 
Next  come  hornbeam,  ash  and  sycamore ;  next,  Norway  maple, 
lime,  horse-chestnut,  sweet-chestnut,  cherry,  rowan  and  ap})le- 
tree,  sometimes  silver-fir. 

Oaks,  elms,  field-maple,  birch,  most  species  of  Pyrus,  Scots 
pine,  black  pine  and  larch  never  suffer  from  bark-scorching. 

(r)  Part  of  tlie  Tree. — Bark-scorching  aft'ects  only  the  clear 
liole  of  a  tree,  and  generally  its  lower  part  from  the  base 
upwards.  The  portion  of  the  stem  which  is  immediately 
above  the  root-stock  suffers  most  where  there  is  no  underwood, 
owing  to  the  heat  reflected  from  the  ground,  while  the  fact 
that  sap  is  earliest  in  motion  near  the  base  of  trees  may 
contribute.  The  taller  the  stem  and  the  higher  the  crown 
above  the  ground,  the  more  exposed  is  a  tree  to  scorching. 
Large  knots  or  low  branches  localise  the  injury  to  the  part  of 
the  stem  which  is  below  them.  Stems  covered  with  moss  or 
lichens  resist  insolation,  and  so  do  trees  that  are  branched 
down  to  the  ground. 

An  example  of  the  bad  etlects  of  pruning  trees  exposed  to 
insolation  may  be  seen  in  the  Mirwart  Estate  in  the  Belgian 
Ardennes,  where  a  number  of  s[)ruce  trees  planted  to  give 
shelter  along  the  eastern  side  of  a  meadow  have  been  pruned 
of  all  their  lower  branches,  and  are  all  badly  scorched. 

*  Hartig  states  that  in  September,  at  10  a.m.,  with  an  air-temperatuie  of 
ti'.t-K"  F.,  the  temperatures  on  the  S.K.  sido  <if  thin-harkcil  bt'ccli  iiml  spruce 
were  U8-t;''  F.  aiul  82-4"  F.,  while  that  of  Scuts  pine  was  t;s'^  F. 


BARK-SCORCHING.  525 

(c/)  Age  of  Tree. — The  trees  mentioned  above  are  exposed  to 
injuries  by  bark-scorching  from  the  age  of  poles  upwards,  but 
large  trees  suffer  more  than  smaller  ones  ;  the  latter,  owing  to 
the  greater  curvature  of  their  stems,  do  not  receive  so  much 
direct  heat  as  the  former,  and  they  radiate  heat  more  freely 
than  large  trees.  In  beech  woods,  where  bark-scorching  is 
frequent,  60-  to  70-  year-old  beech  trees  suffer  most. 

(e)  Position  of  Trees. — Bark-scorching  attacks  trees  standing 
in  the  open  only,  and  especially  those  which  have  been 
recently  exposed,  after  standing  in  a  dense  wood ;  also  trees 
along  the  westerly  and  south-westerly  boundaries  of  a  forest. 
Trees  forming  a  dense  leaf -canopy  are  never  attacked,  as 
their  bark  cannot  become  heated  like  that  of  exposed  trees. 
Exposed  trees  do  not  always  suffer  in  the  first  year  after 
exposure ;  sometimes  four  years  pass  before  bark-scorching 
occurs,  but  this  depends  on  the  state  of  the  weather. 

(/)  Locality. — The  locality  and  its  surroundings,  and  the 
nature  of  the  soil-covering,  may  be  here  considered.  As 
westerly  and  south-westerly  aspects  are  most  exposed  to 
danger,  any  woods  forming  protective  zones  in  these  direc- 
tions prevent  or  reduce  the  effects  of  insolation.  JCrndergrowth 
and  soil-covering  of  dead  leaves  and  humus  are  also  Ui-:eful,  as 
the  reflection  of  the  sun's  heat  from  the  ground  is  much 
greater  when  the  soil,  and  especially  calcareous  or  sandy  soil, 
is  fully  exposed.  The  malady  is  most  frequent  during  the  hot 
months  in  beech  forests. 

4.  Protective  Rules. 

(a)  Avoid  fellings  by  which  beech-  or  spruce-  woods  may 
become  exposed  to  the  west,  south-west,  or  south. 

(h)  Do  not  leave  beech-standards  near  the  threatened 
boundaries  of  a  wood.  In  France  it  has  been  usual  to  lop  the 
side  branches  of  trees  in  woods  bordering  on  roads,  in  order 
to  prevent  injury  to  the  roads  by  drip  and  shade.  This  pre- 
disposes beech  and  other  smooth-barked  trees  to  scorching. 
It  is  better  to  fell  such  trees  and  encourage  advance  growth, 
which  shelters  the  wood,  without  endangering  the  roads. 

(c)  Mix  oak,  elm,  birch  or  conifers  with  beech. 

((/)  Allow    the    trees    on    the    western    and    south-western 


526         PROTECTION  AGAINST  INSOLATION. 

borders  of  a  beech  or  spruce  forest  to  Ijriincli  freely  down  to 
the  ground;  this  may  be  secured  l)y  making  timely  thinnings 
in  young  woods. 

(e)  Avoid  high  prunings  in  the  case  of  beech  standard-trees, 
or  any  pruning  of  beech  or  spruce  trees  growing  in  hedgerows. 

(/)  Protect  the  soil-covering  of  dead  leaves,  moss,  etc.,  and 
preserve  the  undergrowth  along  the  borders  of  a  forest. 

(g)  For  the  protection  of  specially  valuable  avenue  trees, 
their  bark  may  be  smeared  with  a  mixture  of  whitewash,  clay 
and  water,  cow-dung  and  water,  etc. 

Trees  that  have  been  scorched  should  not  be  removed,  as 
they  shelter  trees  behind  them  which  would  otherwise  be 
attacked ;  it  is  better  to  form  a  protective  belt  of  some  shade- 
bearing  species,  and  not  to  remove  the  injured  trees  till  this 
has  attained  a  sufficient  height. 

Section  III. — Heat-crack. 

Beling  states  that  cracks  in  trees  have  been  caused  by 
insolation  ;  this  happens  in  the  spring  (April  and  May),  when 
there  are  considerable  differences  between  the  day-  and  night- 
temperatures,  and  the  ground  being  still  cold,  the  centre  of  the 
tree  does  not  expand  so  much  as  the  bark.  Cracks  are  thus 
formed  on  trees  standing  on  southerly  or  south-westerly  slopes, 
chiefly  on  beech  80  to  70  years  old,  but  also  on  sycamore, 
hornbeam,  oak  and  ash.  The  splits  extend  up  the  stem  from 
near  the  level  of  the  ground  to  20  and  more  feet  in  height. 
Owing  to  the  drying  and  loosening  of"  the  hark,  local  decay 
may  be  introduced  into  the  wood,  but  small  cracks  usually 
close  up  again  without  any  permanent  injury  resulting. 

Schlich  observed  in  the  early  part  of  1895,  during  severe 
frost,  that  the  bark  of  beech-standards  cracked  or  split  when 
the  sun  rose  in  the  morning.  All  such  cracks  or  splits 
occurred  in  the  south-east  or  south  side  of  the  trees,  the 
cracking  being  followed  by  an  outflow  of  sap.  Trees  which 
had  thus  been  injured  in  previous  years  showed  a  considerable 
amount  of  decay  in  the  wood,  having  the  appearance  of  bark- 
scorched  trees. 

As  the  resulting  injuries  are  usually  unimportant,  no  special 
measures  need  be  taken  to  prevent  heat-crack. 


527 


CHAPTER   III. 

PROTECTION    AGAINST    WINDS. 

Winds  may  be  classified  in  various  ways,  by  their  speed,  as 
winds  and  storms ;  their  origin — -land-  or  sea-  winds ;  tlieir 
direction  according  to  the  point  of  the  compass  from  whicli 
they  blow  ;  the  damage  they  inflict  on  forests,  by  drying  up 
the  soil,  impeding  height-growth  and  the  formation  of  a 
regularly-shaped  crown  in  trees,  or  by  breaking  and  over- 
throwing individual  stems  or  whole  woods,  the  last  injury 
being  caused  only  by  storms. 

Wind,  by  J)lowing  caterpillars  from  older  trees  on  to  young 
growth,  may  also  increase  the  damage  done  by  insects  ;  this 
has  been  observed  frequently  in  the  case  of  attacks  by  the  nun 
moth.     Winds  also  spread  the  spores  of  fungi. 

Section  I. — Prevalent  Winds. 
South-westerly  winds  are  most  prevalent  in  Central  Europe, 
especially  during  autumn  and  early  'winter.  They  blow  as 
cool  winds  during  summer,  and  are  comparatively  warm  in 
winter,  and  bring  much  moisture  and  rain-clouds  from  the 
ocean.  Dry  winds  from  the  north-east  and  east  prevail 
generally  during  the  spring,  the  cutting  north-east  wind  on  the 
coasts  of  the  Adriatic  being  termed  bora.  The  well-known 
cold  north-east  wind,  named  mistral,  blows  down  the  Rhone 
Valley,  in  France,  and  in  Switzerland  a  hot  dry  wind  from 
the  south  frequently  prevails  during  the  summer  months  and 
is  termed /o/ut.  Cold  winds  from  mountains  down  on  to  valleys 
and  plains  blow  generally  at  night,  forming  air-cataracts. 

1.  Damage  done. 

A.   General  Account. 

Prevalent   winds   dry    up   and    disperse    the  soil-covering, 

blowing   dead    leaves   from    slopes  and  ridges,  and   heaping 

them  uselessly  in  hollows  ;  they  hinder  the  formation  of  dew, 


528  PROTECTION    AGAINST    WINDS. 

and  spread  the  spores  of  fungi,  and  tlie  seeds  of  forest-weeds. 
Easterly  and  north-easterly  wmds  dry  up  the  soil  and  young 
plants,  and  injure  the  foliage  and  fructification  of  trees.  Strong 
south-westerly  winds  cause  a  misshapen  growth  of  the  crowns 
of  trees,  especially  near  the  sea-coast  and  on  the  south-westerly 
borders  of  forests,  where  the  trees  are  stunted  in  height  and 
have  their  crowns  bent  over  towards  the  east'  (Fig.  241,  p.  513) ; 
they  also  brealc  off  blossoms  and  tender  shoots,  whilst  damp 
winds  near  the  sea-coast  also  injure  trees  by  the  salt  they  carry, 
w'hicli  the  rain  washes  from  their  leaves  into  the  soil,  rendering 
it  salt  and  unsuitable  for  certain  kinds  of  vegetation.  This 
influence  may  be  felt  to  a  distance  of  five  miles  from  the  sea. 
The  results  of  these  injurious  influences  are : — imjDoverish- 
ment  of  the  soil,  a  rank  growth  of  weeds,  failure  of  reproduc- 
tion, languishing  of  young  growth,  loss  of  increment*  and 
forking  of  old  trees,  spread  of  fungi,  etc. 

B.  Damage  under  Special  Conditions. 

(a)  Species. — Broadleaved  trees  suffer  more  than  conifers 
from  dry  winds. 

The  tender  young  foliage  and  inflorescence  of  beech  and  horn- 
beam are  frequently  so  dried  up  by  the  north-east  wind  that 
they  appear  to  have  been  frozen  or  scorched  by  summer  heat. 

The  elm,  oak,  lime  and  birch  are  less  liable  to  damage. 

Where  the  larch  is  exposed  to  south-westerly  gales,  especi- 
ally on  shallow  soils,  it  becomes  sabre-shaped,  curving  out- 
wards and  upwards  from  its  base  ;  this  is  due  to  the  wind 
from  its  seedling  stage  continually  blowing  the  tree  out  of  the 
vertical  direction,  which  it  strives  to  regain  by  continued 
upward  growth.  Orchard  trees  are  similarly  affected,  whilst 
poplars  and  willows  grow  with  their  stems  bending  towards 
the  east. 

As  regards  winds  blowing  from  the  sea,  experience  gained 
near  the  Baltic  and  North  Seas  shows,  that  silver-lir,  elms, 
aspen,  black  poplar  and  birch  withstand  their  action  well. 
The  shrub-like  mountain-pine  (Piiius  montana  var.  iincinata 
Hand.)  also  withstands  the  action  of  winds  along  the  sea-coast 
better  than  Sco.ts  pine,  and  is  extensively  planted  in  Denmark 
and   along   the  Baltic    coast.      In    Britain,    black  pine,    the 


PREVALENT    WINDS.  529 

Corsican  variety  of  Pinus  Laricio,  the  cluster  or  maritime  pine, 
and  of  broadleaved  species,  sycamore,  Norway  maple  and  white 
poplar  are  very  resistant.  Oak  suffers  somewhat  from  saline 
spray,  beech  still  more,  and  the  spruce  most  of  all. 

(h)  Age  of  Trees. — Seedlings  and  little  plants,  especially  in 
sowings  and  plantations,  and  young  coppice-shoots  suffer 
most  severely  from  cutting  winds,  until  the  ground  is  com- 
pletely covered  by  their  interlacing  branches.  Coppice  suffers 
more  than  hi}^h  forest,  especially  when  the  rotation  is  short, 
and  high  forest  suffers  the  less,  the  closer  is  the  leaf-cano^jy. 

((•)  Locality. — The  most  exposed  localities  are  coast  forests, 
cultivated  i)lains  with  hedgerow  trees,  ridges  and  tops  of 
mountains  and  iiills,  valleys  running  east  and  west,  easterly 
aspects  unprotected  by  higher  hills,  unsheltered  plateaux,  etc. 
The  amount  of  soil-desiccation  by  wind  varies  with  the 
nature  of  the  soil  and  wind.  The  faster  the  wind  blows,  the 
more  moisture  is  removed  from  the  soil.  The  damper  the 
soil,  the  more  water  it  loses,  but  deep  soils  suffer  much  less 
than  shallow  soils.  Soil  covered  with  low  vegetation  loses 
the  most  water,  that  covered  with  dead  leaves  and  humus 
least.  Bare  soil  is  intermediate.  Dry  winds,  under  other- 
wise similar  conditions,  remove  more  water  than  moist  winds, 
and  warm  winds  more  than  cold  winds.  Wind  also  reduces 
the  quantity  of  carbon  dioxide  in  the  air  contained  in  the  soil, 
and  reduces  the  soil-temperature,  the  greater  the  velocity  of 
the  wind,  and  the  greater  the  angle  at  which  it  meets  the 
surface  of  the  ground.  Late  spring  and  early  summer  are 
the  most  dangerous  seasons. 

2.  Protective  Rules. 

Tlie  chief  rules  consist  in  the  maintenance  of  a  good  leaf- 
canopy,  especially  in  localities  exposed  to  prevailing  winds. 
Along  sea-coasts,  therefore,  and  in  high  mountainous  regions 
and  other  exposed  places,  natural  regeneration,  selection 
fellings  and  the  formation  of  protective  belts  are  advisable. 

Wherever  clear-cuttings  are  preferable,  after  a  consideration 
of  ail  local  conditions,  the  following  special  rules  should  also 
be  observed  : — 

(a)  After  leaving  a  protective  belt  as  far  as  the  destructive 

F.P.  M  -M 


5;^o 


1'|{()IK(TI()X    ACAINST    WINDS. 


y. 


t 


s.w 


i 


s.  • 

Fi-r.  244. 


action  of  the  wind  precludes  clear-cutting,  establish  narrow 
cutting-areas. 

([))  Planting  with  Ijalls  of  earth  is  advisable ;  if  planting  is 
being  done  during  a  dry  east 
wind,  the  plants'  roots  should 
not  be  exposed  even  for  ten 
minutes,  unless  they  are 
covered   by  damp   moss. 

(c)  Sowings  should  run 
from  north-east  to  south-west, 
and  soil  should  be  heaped  up 
on  the  south-east  side  of  the 
lines,  as  shown  in  Fig.  244  ; 
this  secures  the  young  plants 
against  frost  and  heat  and 
is  also  the  best  protection 
against  dry  winds  from  the 
east  and  south.  It  can,  how- 
ever, be  employed  only  on  flat 
ground,  for  sowings  on  slopes 
must  always  be  horizontal,  in  order  to  prevent  the  soil  and 
seeds  from  being  washed  away  by  rain. 
{cl)  Mix  conifers  with  broadleaved  trees, 
(e)  Belts  of  conifers  20  to  30  feet  wide  as  in  Fig.  245  should 
intervene  between  broadleaved  woods  and  cultivated  land,  and 
should  be  established  along  forest 
roads.  Corsican  pine,  spruce  and 
silver-fir  are  the  best  species  for 
the  purpose,  but  if  the  soil  is  too 
dry  for  them,  Scots  or  Black 
pines  may  be  used.  These  pro- 
tective belts  are  extremely  use- 
ful in  sheltering  woods  from 
drought  and  prevent  the  removal 
of  dead  leaves  by  the  wind, 
damage  by  frost,  etc. ;  the  exter- 
nal trees  should  be  allowed  to  branch  down  to  the  grofliid, 
and  along  forest  roads  there  should  be  a  strip  of  land  free 
from  trees  beyond  the  belt,  to  prevent  the  roads  from  being 


Fig.  245. 
a  Broadleaved  wood. 
1)  Coniferous  wood. 


STORMS.  531 

kept  moist  by  the  drip  from  overhanging  trees.  This  is 
greatly  preferable  to  lopping  the  border  trees  along  a  road- 
side, which,  besides  its  unsightly  appearance,  admits  the 
wind  into  the  forest,  and  exposes  the  bark  to  sun-scorching. 

(/)  All  undergrowth  which  springs  up  along  easterly  and 
north-easterly  forest  boundaries  affords  a  natural  protection 
belt  and  should  be  carefully  preserved. 

(g)  Coppice  should  be  cut  from  the  west,  south-west  or 
north-west  towards  the  opposite  l)earings.  In  high  forests 
this  is  only  permissible  on  plains  which  are  exposed  to  the 
east  and  for  storm-firm  trees  such  as  the  oak. 

Section  II. — Storms. 
1.  Origin  of  Storms. 

All  winds  are  caused  by  differences  in  atmospheric  pressure 
resulting  from  unequal  temperatures  of  the  air  in  different 
localities.  Whenever  the  equilibrium  of  the  atmosphere  is 
thus  disturbed,  a  current  of  wind  sets  in  to  restore  it. 

A  storm  is  a  wind  with  a  velocity  of  at  least  20  to  25  meters 
in  a  second.  Its  approach  is  accompanied  by  a  barometric 
minimum.  A  hurricane  has  at  least  a  velocity  of  35  meters 
per  second. 

A  line  joining  all  places  having  the  same  atmospheric  pres- 
sure, as  indicated  by  the  height  of  the  barometric  column  of 
mercury,  after  compensation  for  the  elevation  of  tbe  place 
above  sea-level  and  for  temperature,  is  termed  an  isobar. 

If  maps  are  drawn,  as  in  the  Times'  weather  reports,  show- 
ing the  ditlerent  isobars  for  every  tenth  of  an  inch,  it  will  be 
noticed  that  they  surround  tracts  from  which  either  the  pres- 
sure decreases  in  all  directions,  termed  barometric  maxima  or 
anticyclones ;  or,  from  which  the  pressure  similarly  increases, 
which  are  termed  centres  of  depression,  barometric  minima  or 
cyclones. 

The  wind  always  blows  from  the  regions  of  higli  pressure 
towards  the  depressions,  i.e.,  from  an  anticyclonic  region 
towftds  a  centre  of  depression  ;  it  does  not,  however,  blow  in 
a  direction  nornuxl  or  perpendicular  to  the  isobars,  but  greatly 
inclined  to  this,  owing  to  the  effects  of  the  earth's  rotation, 

M  M  2 


532  PROTECTION    AGAINST    WINDS. 

which  gives  it  a  twist  to  the  right  in  the  northerly  hemisphere. 
The  strength  of  the  wind  varies  with  the  barometric  firadicnt, 
or  difference  in  atmospheric  pressure  at  places  distant  one 
geographical  mile  normal  to  the  isobars.  The  closer,  there- 
fore, the  isobars  are  for  any  difference  in  the  height  of  mer- 
curial column,  the  greater  is  the  gradient  and  the  stronger  the 
wind. 

The  isobars  become  crowded  together  wherever  the  pressure 
is  lowest,  ayd  this  fact,  combined  with  the  twist  to  the  right 
of  the  winds  rushing  in  from  all  directions  to  fill  a  depression, 
causes  the  revolving  storms  also  termed  cyclones,  the  absolute 
axes  of  which  are  more  or  less  calm.  Thus  on  the  southern 
side  of  a  depression,  the  wind  blows  from  the  S.W.,  on  its 
western  side  from  N.W.,  on  its  northern  side  from  N.E.,  and 
on  its  eastern  side  from  S.E. 

The  isobars  are  closest  together  on  the  western  sides  of 
depressions,  so  that  the  strongest  storms  come  from  a  westerly 
direction  (S.W.  to  N.W.).  The  depressions  usually  pass  to 
the  north  of  Central  Europe,  and  traverse  the  continent  from 
west  to  east,  so  that  storms  usually  begin  blowing  from  S.E. 
and  gradually  change  to  S.,  S.W.,  W.,  and  N.W.  Most  of 
these  storms  travel  across  the  British  Isles,  having  originated 
in  the  Atlantic  ocean  or  Gulf  of  Mexico,  but  the  south-easterly 
direction  of  the  wind  before  a  cyclone  is  not  very  noticeable  here. 
Powerful  storms  therefore  depend  on  the  existence  of 
barometric  depressions,  which  may  be  onl}'  partial  or  irregular 
interruptions  of  an  isobar,  in  which  case  the  storm  extends 
over  a  limited  area  only.  Violent  storms  of  limited  extent 
but  withs  teep  gradients  that  do  considerable  damage  over  a 
narrow  zone  of  country,  are  termed  tornados. 

The  direction  of  winds  may  be  considerably  modified  in 
mountainous  countries,  by  the  spurs  of  the  mountains  as  well 
as  the  directions  of  the  valleys.  Thus,  a  west  wind  may  be 
converted  into  a  north  or  south  wind  during  its  progress 
through  a  valley. 

It  is  a  still  more  frequent  case  for  a  south-west  wind  to 
become  a  south  wind,  and  a  north-west  wind,  west. 

Tliese  local  wind-directions  must  be  considered  whenever  a 
working-plan  is  prepared. 


STORMS.  f)33 

The  rates  of  storms  are  yiven  as  follows  by  House  : — 

Yards  iMiles 

per  second.         j)er  hour. 

Storm,  or  tempest       ...  24  50 

Great  storm        ....  29  60 

Hurricane  .....  40  80 

Destructive  hurricane           .         .  41)  100 

2.  Damacfc  done. 
A.  General  Account. 

Storms  shake  the  roots  of  trees  up  and  down  in  the  ground 
and  may  either  give  a  tree  a  decided  leaning  in  a  particular 
direction,  or  tear  it  out  of  the  ground  by  its  roots  and  with 
the  earth  adhering  to  them,  or  break  its  stem  or  branches. 
Such  uprooted  or  broken  trees  are  termed  icindfaUs. 

Whether  the  tree  is  blown  down  or  broken  depends 
partly  on  the  intensity  of  the  storm  and  partly  on  the 
relative  power  of  resistance  of  its  roots  or  stem.  Breakage 
happens  when  the  roots  resist  better  than  the  stem,  windfall 
when  the  roots  are  the  weaker.  Breakage  may  also  be  due 
to  one  tree  falling  on  others.  The  amount  of  resistance 
to  storms  which  the  roots  or  stem  of  a  tree  offers,  equal  con- 
ditions being  presupposed,  depends  on  the  nature  of  the  soil 
(its  compacity  and  degree  of  moisture,  e.g.,  whether  its  resist- 
ance has  been  weakened  by  heavy  rain  before  a  storm),  and 
that  of  the  loealiti/  (plains,  or  hillsides,  aspect,  gradient,  etc.). 

Independently  of  the  above,  the  storm -firmness  of  our  trees 
varies  according  to  species,  lenf/th  of  bole,  nature  of  crown, 
sotoidness  of  the  wood,  densittf  of  crop,  mode  of  formation,  and 
tendimi,  as  well  as  on  other  local  circumstances.  Each  of 
these  factors  will  be  considered  separately. 

The  roots  of  the  trees  that  are  stretched  by  the  wind  are 
termed  anchor-roots,  those  on  the  lee  side  of  the  tree  projy-^ 
roots.  The  prevailing  opinion  is  that  the  anchor-roots  hold 
up  the  tree  against  a  storm,  as  the  anchor  holds  a  ship. 
Hesse,  however,  agrees  with  Nordlinger  in  attaching  more 
importance  to  the  prop-roots.  In  support  of  this  he  states 
that  in  a  roadside  avenue  running  N.  and  S.,  the  trees  on  the 
\\ .,  having  their  prop-roots  in  the  firm  road,  hold  better  against 


5:34  PROTECTION   AGAINST    WINDS. 

storms  than  those  on  the  E.  side  of  the  avenue,  tliat  have 
their  prop-roots  in  softer  soil. 

Storms  not  only  overthrow  single  trees,  l)ut  also  whole  woods. 
A  wood  may  have  narrow  clearings  cut  into  it  by  storms  corre- 
sponding to  their  direction,  or  large  blanks  may  be  made. 

Breakage  may  be  of  stem,  fork,  crown,  or  branches  ;  the  stem 
may  l)e  broken  off  close  to  the  ground,  or  at  some  distance  al)ove 
it,  and  whirlwinds  frequently  twist  the  entire  crown  off  trees. 

The  damage  done  by  storms  may  be  direct  or  indirect. 

To.  the  former  class  belong : — Loss  of  increment  and 
breakage  of  timber,  which  may  become  only  fit  for  firewood ; 
damage  to  young  growth  owing  to  the  breakage  of  underwood 
by  trees  standing  over  it  which  have  been  blown  down ; 
increased  cost  of  exploitation  or  of  reproduction  of  woods ; 
reduced  prices,  owing  to  an  excess  of  material  being  suddenly 
thrown  on  the  market ;  irregularities  in  age-classes  and  in 
carrying  out  working-plQ,ns,  also  disorder  in  thinnings  and  in 
preparatory  fellings.  The  disturl)ance  of  a  forest  working- 
plan  ma}'  be  so  great,  that  it  may  become  necessary  to 
recalculate  the  annual  yield  of  a  forest,  and  to  prepare  a  new 
table  of  annual  felling-areas. 

Indirect  damage  done  by  storms  is  chiefly  confined  to 
invasions  of  weeds  in  the  blanks  and  regeneration-areas 
where  the  trees  have  been  blown  down,  and  to  attacks  of  bark- 
beetles. 

B.  Damage  under  Special  Conditions. 

(a)  Sj^ecies  of  Tree. — Conifers  are  far  more  exposed  to 
damage  than  broadleaved  species.  Extensive  destruction  of 
broadleaved  woods  by  storms  is  comparatively  rare. 

It  would  1)0  difficult  to  draw  up  a  comparative  table  of  trees 
of  different  species  according  to  their  capacity  to  withstand 
storms,  as  the  amount  of  damage  done  is  greatly  modified 
by  local  circumstances ;  but  evergreen  foliage  and  shallow 
root-systems  render  trees  liable  to  be  broken  or  blown  over. 
As  these  two  qualities  are  united  in. the  spruce,  this  species  is 
specially  liable  to  damage  by  storms,  as  experience  has  proved. 
If,  at  any  time,  other  trees  sufYer  more  than  the  sprtice, 
this  is  due  to  the  nature  of  the  soil,  to  the  extraordinary 
violence  of  the  storm,  or  some  other  special  circumstance. 


STORMS.  535 

When  species  such  as  silver-fir,  or  Scots  pine,  with  strong 
root-systems,  are  hindered  from  developing  them  normally, 
owing  to  the  nature  of  the  suhsoil,  they  are  exposed  to  danger 
equally  with  the  spruce,  and  even  more  so  ;  for  in  such  cases 
they  are  compelled  to  have  shallow  root-systems  which,  unlike 
the  spruce,  they  rarely  develop  evenly  in  all  directions. 
Danger  is  also  increased  in  the  case  of  the  Scots  pine  by  the 
higher  centre  of  gravity  it  possesses  than  the  spruce. 

A  list  of  species  arranged  in  ascending  order  of  storm- 
firmness  can  therefore  be  drawn  up  only  after  allowing  for 
the  effects  of  local  circumstances  on  each  species,  and  pre- 
supposing a  rational  treatment  in  accordance  with  sylvicultural 
requirements. 

From  this  point  of  view,  conifers  are  arranged  in  the  follow- 
ing order  : — Spruce,  silver-fir,  pines  and  larch.  Of  the  pines, 
the  mountain  and  Cembran  pines  are  most  storm-firm,  then 
the  Corsican  pine,  the  Black  pine,  and  the  cluster,  Weymouth 
and  Scots  pines. 

As  regards  broad  leaved  species,  those  which  are  shallow- 
rooted,  such  as  aspen,  birch,  beech,  and  hornbeam,  are  least 
storm-firm.  The  beech  is  more  frequently  blown  down  than 
any  of  these  species,  because  it  is  most  abundantly  grow-n.  In 
the  woods  above  G^rardmer,  in  the  Vosges,  the  porportion  of 
beech  increases  under  natural  regeneration  with  the  altitude, 
in  the  mixed  forest  of  silver-fir,  spruce,  and  beech ;  and  at  the 
crest  of  the  mountains,  4,000  feet,  beech  alone  remains,  the 
conifers  being  unable  to  resist  the  prevailing  westerly  gales. 
Tlie  following  trees  are  fairly  stoim-firm  : — ash,  sycamore, 
Norway  maple,  elm,  alder,  lime  and  walnut;  the  deep-rooted 
oaks  withstand  storms  best  of  all. 

(h)  A(/c  of  Tree. — Storms  chiefly  damage  woods  of  advanced 
age,  the  second  half  or  last  third  of  a  rotation  being  most 
endangered.  , 

Extensive  damage  is  rare  in  woods  under  sixty  years  of 
age,  and  occurs  only  upder  exceptional  conditions,  sucii  as 
shallow-rootedness  of  young  woods,  soil  without  mucli  con- 
sistency owing  to  saturation  by  rain,  woods  in  very  exposed 
localities  or  when  assailed  by  exceptionally  violent  storms. 

Damage  to  young  trees  consists  more  in  causing  them  to 


536  PROTKCTION    AfiAIXST    WINDS. 

deviate  from  tlie  vertical  position,  less  by  uprooting,  and  less 
,  still  in  breakage. 

In  the  storm  on  the  Baltic  coast  in  1872,  in  the  Greifs^Yald, 
25-years-old  Scots  pines  were  affected.  In  187G,  15  to  20- 
years-old  spruce  and  Scots  pines  were  seriously  damaged.  In 
some  pole-woods  25  to  30  per  cent,  of  the  stems  were  bent  an 
angle  of  30  degrees  towards  the  east  and  north-east. 

((•)  Si/stem  of  Manar/ement. — High  forests  are  most  exposed 
to  danger  from  storms.  The  shelterwood  compartment  system 
leaving  mother  trees  evenly  distributed  over  the  felling-area, 
is  most  endangered.  In  localities  exposed  to  storms  (mountain 
sides,  etc.)  this  system  is  inapplicable,  as  the  mother  trees  are 
inevitably  blown  down. 

Whether  uneven-aged  and  irregular  Selection  forests  suffer 
more  from  storms  than  the  even-aged  woods  of  the  Clear- 
cutting  system,  is  still  an  open  question,  which  can  only 
be  answered  after  thoroughly  considering  the  modifying 
influence  of  localities,  and  the  degree  of  skill  with  which  the 
woods  have  been  treated.  Hesse  believes  that  the  Selection 
and  Group  S3'stems  give  more  security  against  storms  than 
the  Clear-cutting  system,  as  the  trees  in  the  latter  are  more 
crowded  and  have  weaker  roots,  but  under  the  former  systems 
the  trees  to  be  felled  must  be  very  carefully  selected. 

Among  the  coppice  systems,  that  of  lopping  side  branches  is 
the  worst,  as  trees  so  treated  have  long  narrow  crowns,  on  which 
the  wind  can  exert  leverage.  Pollards  suffer  less,  and  ordinary 
coppice  least  of  all.  Coppice-with-standards  is  also  storm- 
firm,  as  only  the  standards  can  suffer,  and  damage  to  these 
is  inconsiderable,  owing  to  their  strong  root  develo^mient  and 
the  uniformity  of  their  crowns,  due  to  their  growth  in  the  open. 

(d)  Nature  of  Stem. — Long,  cylindrical  stems  with  elevated 
and  expanded  crowns,  having  high  centres  of  gravity,  and 
affording  strong  leveraj^e  to  the  winds,  are  greatly  exposed  to 
damage  by  storms.  Thus  standards  in  high  forest  above 
young  growth  are  peculiarly  liable  -to  be  thrown  or  broken. 
Damaged  or  sickly  trees,  such  as  forked  trees,  those  with 
decayed  roots;  trees  injured  by  game,  insects,  cankers,  fungi, 
cup-shake,  bark-scorching,'  etc.,  are  very  liable  to  windbreak  ; 
this,  as  a  rule,  occurs  at  the  damaged  j)lace. 


STORMS.  537 

Uprooting  of  the  tree  with  the  soil  attached  to  its  roots  is 
most  frequent  in  the  case  of  spruce  or  beech. 

Breakage  of  crown  or  branches  is  most  common  in  the  case 
of  Scots  pine,  alder,  ash  and  robinia.  The  forked  l)ranches 
and  crown  of  the  two  latter  species  are  frequently  broken  by 
storms.  In  the  case  of  oaks  it  is  chiefly  the  dry  branches  of 
stag- headed  crowns  which  are  blown  off  by  storms.  In  the 
Vosges,  a  distinction  is  made  between  silver-fir  trees  with  a 
U  fork  and  those  with  a  V  fork,  the  latter  being  more  liable  to 
breakage.     Cankered  silver-fir  are  very  liable  to  breakage. 

(<;)  Locality. — In  Germany,  forests  on  hills  and  low 
mountain-chains  are  more  affected  by  storms  than  those  in 
higher  mountainous  regions.  During  the  ten  years,  1870 — 80, 
in  the  Thiiringer-Wald  and  the  Harz,  damage  by  storms  was 
chiefly  at  altitudes  of  between  800  and  1,800  feet ;  but  in  1876, 
extended  to  2,800  feet.  This  is  because  at  higher  altitudes 
spruce  trees  are  shorter  in  the  stem  than  those  growing  lower 
down,  are  also  grown  less  crowded  with  low  crowns  in  Selection 
forests,  and  have  thus  greater  powers  of  resistance  against 
storms  than  the  crowded  lanky  stems  of  lower  altitudes. 

The  confir/uration  of  the  ground  has  a  marked  influence  on 
the  amount  of  damage  done  to  forests  by  storms. 

Gentle  westerly  slopes  bordering  on  extensive  plains  or 
plateaux  suffer  greatly,  and  so  do  outlying  hills  and  mountain 
ridges ;  also,  narrow  valleys  running  from  the  west  or  south- 
west tow^ards  the  east  or  north-east.  The  damage  is  then 
done  on  the  north  and  south  slopes  of  these  valleys,  which 
the  wind  attacks  in  Hank.  Every  bend  in  the  valley  reduces 
the  violence  of  the  wind.  To  endangered  localities  also  belong  : 
hills  at  the  end  of  narrow  valleys  or  outliers  that  project  into 
them  and  steep  slopes  directly  in  the  way  of  the  storm. 

A  storm  that  descends  a  hillside  is  much  more  dangerous 
than  one  blowing  up-hill.  Whenever  south-westerly  winds 
prevail,  a  storm,  after  crossing  -a  mountain  ridge,  must 
descend  its  north-easterly  slope.  If  the  west  or  south-west 
slopes  of  the  hill  are  denuded  of  trees,  or  if  the  wind  has  to 
find  its  way  across  the  ridge  through  narrow  felling-areas 
between  high  woods,  or  by  funnel-shaped  ravines,  the  damage 
done  on  the  north-easterly  slope  will  be  increased,  as  the  air 


538 


PROTECTION    AGAINST    WINDS. 


becomes  condensed  owing  to  the  confined  space  in  wliicli  it 

moves,  and  this  increases  the  violence  of  the  storm. 

It  is  found  that  storms  do  more  damage  down-liill    than 

up-hill,  and  for  the  following  reasons  : — 

i.  The  root-system  of    individual  trees  is  usuall}^   weaker 

down-hill  than  up-hill.     Not  only  the  anchor-roots,  but  also 

the  prop-roots  are  more  oblique  in  the  soil  to  the  wind- 
direction  on  the  easterly 
aspects,  i.e.,  away  from  the 
wind.  The  descending  storm 
therefore  finds  only  a  feeble 
resistance  in'the  roots  ;  the 
wind  blowing  up-hill  has  to 
overcome  not  only  the  resis- 
tance of  the  anchor-roots,  but 
also  those  of  the  prop-roots, 
ii.  An  ascending  ^ind  has 
to  contend  with  the  friction 
of  the  tree-crowns,  as  well 
as  of  the  soil,  which  reduces 
its  force.  Moreover,  the 
prop-roots  of  the  trees  on 
the  western  slopes,  exposed 
to  the  wind-direction,  are 
more  vertically  inclined  to 
the     latter,    and     therefore 

offer  a  stronger  resistance,  than  on  the  easterly  slopes, 
iii.  The  centre  of  gravity  of  a  tree  has  to  be  raised  less 

when  blown  over  from  aljove  than  from  below,  as  the  annexed 

diagram  shows : — 

Here  s  is  the  centre  of  gravity  of  the  tree,  and  w,  wi,  two 

roots,  and  if  the  tree  is  to  be  thrown  up-hill  by  the  wind,  s 

must  be  raised  through  a  b ,-  ii  down-hill,  through  c  d,  which 

is  less  than  a  h.     Tiie  greater  the  gradient  of  the  slope,  the 

more  endangered  is  the  tree. 

The  nature  of  the  .soil  exercises  an  unmistakeable  influence 

on  the  extent  of  the  damage  done  by  storms. 

Shallow,  loose,  spongy  soil  afTords  a  bad   root-hold  ;  tliis 

explains  the  great  amount  of  windfall  which  occurs  on  moors 


Fi-.  246. 


STORMS.  539 

and  sandy  soils ;  soils  above  a  subsoil  of  stiff  clay,  into  which 
the  trees'  roots  do  not  penetrate,  are  also  very  subject  to  wind- 
fall. It  has  been  observed  that  windfall  in  the  Schwarzwald  is 
more  frequent  on  the  red  sandstone  formation  than  on  gneiss, 
granite,  basalt  or  porphyry.  In  woods  that  have  been  planted 
on  the  sites  of  old  fields,  windfall  is  frequent,  owing  to  the 
looseness  and  comparative  poverty  of  the  soil  in  mineral 
matter.  Soils  iu  which  root-rot  frequently  occurs,  such  as 
calcareous  soil,  or  land  with  a  wet  subsoil,  are  liable  to  windfall. 

A  high  soil-covering,  such  as  heather,  broom,  thorny  or 
shrubl^y  undergrowth,  is  beneficial,  a^  these  plants  bind 
together  the  particles  of  soil,  and  also  exercise  considerable 
friction  on  the  air  in  motion. 

The  state  of  the  weather  before  and  at  the  commencement 
of  the  storm  also  exercises  considerable  influence  on  the 
damage  done. 

Heavy  rainfall  accompanying  a  storm  greatly  diminishes 
the  coherence  of  the  soil,  and  increases  the  danger  of  up- 
rooting, its  effects  vary  of  course  with  the  nature  of  the  soil. 
This  was  the  case  on  the  occasion  of  the  terrible  storms  in 
1872  and  1874.  Frost,  on  the  contrary,  greatly  increases  the 
coherence  of  the  soil,  especially  when  the  ground  is  covered 
with  snow. 

(./')  Density  of  Crop. — Trees  grown  in  the  open,  owing  to 
their  well-developed  root-systems,  and  low  pyramidal  crowns, 
withstand  storms  much  better  than  stems  which  have  been 
drawn  up  in  dense  woods.  Trees  recently  exposed  in  thin- 
nings and  regeneration  fellings  suffer  most.  The  latter 
improve  in  their  powers  of  resistance,  as  they  get  accus- 
tomed to  their  open  position.  Their  root-systems  become 
enlarged ;  in  crowded  woods,  however,  the  stems  afford  one 
another  mutual  protection  against  the  wind. 

Damage  is  considerably  greater  in  isolated  woodlands  than 
in  extensive  forests,  as  the  various  crops  in  tlie  latter  afford 
one  another  mutual  support. 

{(j)  Season. — Storms  may  occur  at  any  season  of  the  year,  but 
the  most  destructive  storms  are  during  the  six  months  between 
the  autumnal  and  vernal  equinoxes.  Storms  in  spring  are  more 
dangerous  than  in  autumn,  as  the  soil  is  tlien  generally  less 


51(»  rROTECTION    AHAINST    WINDS. 

finii.  Since  1870,  damage  to  Piussian  forests  by  storm,  snow 
and  rime  have  been  recorded  in  all  the  Royal  Forest  districts, 
and  the  results  pul)lished  by  the  directors  of  the  Forest 
experimental  stations.  This  praiseworthy  undertaking  should 
be  followed  by  all  State  Forest  Administrations. 

3.  Ixrr/istcr  of  Storms. 
During  the  past  century,  the  following  are  the  dates  of  the 
most  widespread  and  disastrous  storms : — 

1800  (3rd  and  9th  November,  especially  in  the  Harz). 

1801  (29th  and  30th  January). 

1833  (17th  and  18th  December). 

1834  (4th  January). 

1830  (29th  November  and  24th — 2()th  December,  from 
the  E.). 

1839  (30th — 31st  October,  especially  in  the  Harz,  from 
the  E.). 

1842  (3rd  Uny). 

1853  (14th  and  15th  December,  from  S.E.). 

1866  (16tli  November). 

1867  (8th  April). 

1868  (7th,  11th,  and  29th  December). 

1869  (17th  December). 

1870  (26th  and  27th  October). 

1872  (12th  and  13th  November,  especially  near  the  Baltic, 
from  the  N.E.). 

1875  (8th  and  13th  November). 

1876  (12th  and  13th  March).  In  this  storm,  about  thirty 
million  cubic  feet  of  timber  were  blown  down  in  the  State 
and  Communal  forests  of  Hesse,  or  84  cubic  feet  per  acre, 
being  125  per  cent,  of  the  total  annual  yield  of  the  forests. 
The  same  storm  cleared  24  cubic  feet  per  acre  in  the  Saxon 
forests,  or  40  per  cent,  of  their  fixed  annual  yield.  During 
the  same  year,  350,000  cubic  feet  of  broadleaved  trees  were 
blown  down  in  the  Forest  of  Compiegne. 

1877  (30th  and  31st  January,  and  10th  and  12th 
February). 

1879  (20th  and  21st  February,  25tli  June,  20th  November, 
and  5th  December). 


STORMS.  541 

1880  (21st  October). 

1881  (14th  and  15th  October). 

1883  (17th— 19th  October). 

1884  (20th  and  28th  January). 

1885  (15th  October). 

1888  (24th— 26th  November). 

1890  (23rd,  24th  and  27th  January). 

1892  (29th— 30th  March,  m  the  Vosges ;  from  E.). 

1893  (16th  and  17th  November).  Terrific  storms  over  the 
north  of  England  and  Scotland  accompanied  by  violent 
rain,  the  wind  blowing  at  90  miles  an  hour  in  the  Orkneys; 
1,850,000  tree's,  valued  at  X'282,268,  were  blown  down  in 
Perthshire  and  Forfarshire,  the  only  conifers  resisting  the  gale 
being  Corsican  and  maritime  pines. 

1894  (12th  February  and  22ud  December).  The  December 
storm  was  similar  to  that  of  1893,  and  only  did  less  damage 
to  the  Highland  woods  because  there  were  fewer  trees  left 
to  be  blown  down.  Great  numbers  of  rooks,  starlings,  and 
other  birds  were  entangled  in  the  branches  of  trees  and  killed, 
or  blown  into  the  sea. 

1B95  (5th— 7th  and  12th— 13th  December;  chiefly  in  S. 
German^',  but  also  in  Schleswig-Holstein  and  the  Harz). 

1895  (5th— 7th  October,  from  N.E.). 

1898  (4th— 7th  December). 

1899  (12th— 13th  January). 

1900  (14th  February  ;  28,000  trees,  including  15,000  oaks, 
blown  down  in  the  Forest  of  Berce,  Sarthe). 

1902  (13th  February;  292,500  cubic  feet  of  timber,  chiefly 
spruce,  blown  down  in  Forest  of  Gerardmer,  Vosges ;  from 
N.E.). 

Taking  a  general  view  of  the  storms  in  Central  Europe, 
during  the  past  century,  the  years  1801,  1833,  1868,  1876, 
1893,  and  1894,  have  been  the  worst,  and  there  has  been,  on 
the  average,  one  destructive  storm -year  every  three  years. 

Whirlwinds  are  of  rare  occurrence  in  Central  Europe,  and 
are  usually  only  of  limited  extent  and  short  duration.  On 
the  1st  August,  1877,  a  whirlwind  fifty  miles  to  the  north  of 
Berlin  destroyed  three-and-a-half  million  cubic  feet  of 
standing    timber    over    a    breadth    of    two-and-a-half    miles. 


542  PKOTKCTION    AGAINST    WINDS. 

The  cofist  districts  between  the  mouths  of  the  Mississippi 
river  and  Charleston  are  subject  to  terrific  hurricanes,  and  in 
August,  1893,  scarcely  a  tree  was  left  standing  in  the  islands 
there,  nearly  2,000  people  were  killed,  and  .^1,000,000  worth 
of  property  destroyed,  the  wind  having  blown  at  the  rate  of 
125  miles  per  hour.* 

4.  Protective   Hides. 
a.   Uurimj  the  Fonnation  of  Woods. 

i.  Favour  the  cultivation  of  broadleaved  species  wherever 
this  is  possible.  The  damage  done  by  storms  during  the  last 
ten  years  is  a  warning  to  foresters  who  are  so  ready  to  convert 
broadleaved  into  coniferous  forests ;  this  should  be  done  only 
in  cases  of  extreme  urgency. 

ii.  Drain  damp  localities  before  making  regeneration- 
fellings. 

iii.  Use  strong  transplants  4  to  6  feet  apart,  so  as  to  ensure 
the  growth  of  sturdy  trees.  Planting  spruce  gives  better 
results  than  sowing  it. 

iv.  Mix  deep-rooted  species  with  shallow-rooted  ones ;  for 
instance,  mix  oak,  ash,  sycamore,  larch,  or  Scots  pine  with 
beech  and  silver-fir,  and  silver-fir,  beech  and  larch  with  spruce. 

Von  Wiehl  (Olmiitz)  placed  rows  of  storm-firm  trees  in 
spruce  woods  every  150  metres,  five  or  six  rows  of  oak, 
sycamore,  Scots,  Weymouth,  and  Cembran  pines,  according  to 
the  soil  and  locality,  transversely  to  the  storm-directioii,  in 
flat  land  from  N.  to  S.,  elsewhere  parallel  to  the  sides. 

V.  Maintain  protective  belts  along  the  boundaries  of  a  forest, 
where  prevailing  winds  are  to  be"  feared,  especially  along  farms 
and  neighbouring  woodlands.  Boundary  ditches  should  not 
be  dug  along  these  boundaries,  as  they  cut  through  the  roots 
of  tiie  nearest  trees. 

b.  iJurinji   Tendhiij. 

i.  Early,  frequent  and  moderate  tldiminys  should  be  made, 
so  as  to  ensure  normal  root-systems,  sturdy  stems,  and  regu- 
larly shaped  crowns.  During  the  thinnings,  as  Jar  as  is 
possible  without  interferiiu/  with  the  proper  density  of  the  crop, 
all  trees  should  be  removed  which  have  suffered  injury  to  their 

*   "  Scribiier's  Magazine,"  Fein uary,  is'.i). 


STORMS.  543 

bark,  or  which  are  forked,  diseased  or  affected  with  fungi.  If 
tlie  proper  den  sit}'  of  the  crop  would  be  impaired  by  wholesale 
removal  of  bad  trees,  begin  with  the  worst  and  remove  the 
others  in  future  thinnings.  It  is  better  in  thinning  spruce- 
woods  not  to  dig  up  stumps,  as  in  so  doing  the  roots  of 
neighbouring  trees  may  be  cut  through.  Heavy  thinnings  in 
lanky  and  hitherto  densely  growing  woods  are  dangerous. 

ii.  Trees  along  the  borders  of  a  forest  should  be  allowed  to 
branch  low  down  the  stem. 

iii.  Endangered  border  trees  standing  over  3'oung  growth 
may  be  temporarily  preserved  by  thinning  out  their  crowns, 
and  cutting  those  branches  which  extend  at  right  angles 
to  the  direction  of  the  prevailing  wind.  This  has  been 
successfully  carried  out  with  spruce  at  Stammheim,  in 
Wiirttemberg. 

iv.  Carefully  avoid  all  causes  leading  to  defects  in  trees; 
thus,  resin-tapping  should  be  stopped  in  spruce  forests, 
deer  which  peel  trees  should  be  shot,  and  careful  forest 
protection  secured. 

c.  During  Fellings. 

i.  Avoid  very  long  rotations,  as  the  area  of  a  forest  exposed 
to  danger  from  storms  increases  in  proportion  to  the  length 
of  the  rotation.  Thus,  considering  that  danger  from  storm 
commences  when  the  trees  are  fifty  years  old,  we  have : — 

With  120  years'  rotation  j^^ths  of  the  area  endangered. 
90      ,,  „  fths 

60      „  „  ith 

ii.  All  greatly  exposed  places  in  mountainous  regions  should 
be  regenerated  by  the  Selection  system,  and  the  slopes  should 
not  be  touched  till  the  summit  has  been  regenerated. 

iii.  Regeneration  in  narrow  strips  commencing  in  the  direc- 
tion opposed  to  the  prevailing  wind,  should  be  substituted  for 
regeneration  extending  at  once  over  a  whole  compartment, 
especially  in  spruce  forest. 

In  the  Black  Forest,  where  silver-fir  predominates,  the 
group  system  of  felling  in  patches,  gives  excellent  results,  as 
plentiful  natural  regeneration  results. 


,u 


I'RO'iECTiox  a(;ainst  winds. 


iv.  Woods  should  always  be  regenerated  in  the  direction 
opposed  to  the  pnvuiliti<i  uinds,  that  is,  generally,  from  east  or 
north-east  to  west  or  south-west,  so  as  to  secure  a  constantly 


-(S.E 


1     2    3     •!      r,     U     7     8  1-4  1-:!  r  1  r  1   r 

Fig.  247. — Normal  arrangement  of  age-classes  in  a  wood  ;  r,  length  of  rotation. 

graduated  succession  of  young  woods  on  the  windy  side  of  the 
older  woods.  Nothing  can  ward  off  storms  better  than  such  a 
slope  of  trees  as  is  shown  in  Fig.  247. 

As  such  a  succession  of  felling-areas  may  encourage  insect 
attacks  and  would  not  be  practicable  over  the  whole  area  of  a 
forest,  it  is  usual  to  arrange  the  age-classes  in  a  number  of 
cutting-series,  running  more  or  less  parallel  to  one  another 
through  the  forest  from  east  or  north-east  to  west  and  south- 
west. Age-classes  are,  however,  seldom  so  arranged  that  an 
old  wood  will  not  occasionally  be  found  directly  opposed  to  the 
force  of  the  wind,  after  it  has  been  exposed  by  felling  another 
mature  wood  to  the  west  of  it,  and  in  such  cases,  a  severance- 
felling  is  required. 

This  is  a  narrow  clearing  made  through  a  wood,  to 
strengthen  the  border  trees  on  its  weather  side,  so  that  by 
the  extension  of  their  crowns  and  root-systems,  they  may 
protect  the  dense  wood  beyond  them  from  storms.  Severance- 
fellings  should  be  forty  to  fifty  feet  broad,  and  as  nearly  as 
possible  at  right-angles  to  the  direction  of  the  prevailing 
wind ;  they  nmst  be  made  before  the  trees  are  too  old  to 
respond  to  the  increased  exposure  to  light.  Spruce  woods,  in 
which  a  severance-felling  is  to  be  made,  should  not  be  more 
than  20 — 80  years  old.     The  cleared  space  should  be  at  once 


STORMS. 


545 


planted  up,  and  thus  itself  form  a  protective  zone  when  the 
woods  beyond  it  have  been  felled. 

The  young  wood  must  be  10 — 20  years  old,  before  the  felling 
of  the  old  wood  in  front  of  it  begins.  Severance-fellings 
should  not  be  risked  in  woods  more  than  50  years  old. 

Severance-fellings  favour  the  system  of  small  felling-areas, 
which  have  many  great  advantages.  "We  must  not,  however, 
go  too  far  in  this  matter.  There  is  certainly  a  loss  of  yield 
in  making  a  severance-felling,  as  part  of  an  immature  crop 
is  sacrificed.  The  financial  aspect  of  the  question  must 
therefore  be  considered,  and  whether  the  danger  from  storms 
justifies  the  sacrifice. 

Severance-fellings  are  very  extensively  used  in  the 
Thiiringian  forest,  and  in  the  Saxon   State  forests. 


When  felling  actually  commences  in  a  crop  protected  by  a 
severance  felling,  a  protective  belt  should  be  left  along  its 
eastern  border,  consisting  of  a  double  or  treble  row  of  trees, 
the  crowns  of  which  have  been  thinned  by  lopping  away  some 
of  their  branches,  as  shown  in  Fig.  248. 

V.  Felling-areas  should  have  long  straight  boundaries,  as 
fellings  in  outlying  corners  of  a  forest  may  easily  admit 
storms. 

vi.  A  system  of  rides  with  storm-firm  borders  should  be 
laid  out,  which  afifords  protection  against  storms. 

The  principal  rides  should  l)e  parallel  to  the  storm-direction, 
and  the  secondary  rides  at  right  angles  to  it,  so  as  to  face  the 
storms. 


F.P. 


NN 


540 


PROTIXTION    AGAINST    WINDS. 


Stern  h  e  r<i  r 


p£ ' 


&!'.ll 


'1 


?Ai^ 


ffrr,^.      /"^"^^ 


T'^Kmw-/-^ 


'HHSL 


Scale  ^^1 


III. 


II. 


D 


10  years  old.  30  years.  .50  years.  70  year.s 

Fig.  249.— Plan  of  jiart  of  tlic  Zellaer  Forest,  with  3  severance-fellings,  a  It  c. 


ttMi 


70 

Jo  \ 

i 

SO 

30 

10 

1 

SO                    1 

SO 

30 

V 

Fig.  250.  —Section  of  the  wood  along  A  B. 

Tlie  numbers  refer  to  the  average  ag^of  the  wood,    alt  c  Severance-fellings,    d  Koad. 

The  10-year-old  wood  is  a  protective  plantation. 


STORMS.  547 

Fellings  in  high  forest  follow  one  another  from  east  or 
north-east  to  west  or  south-west,  according  as  a  compartment 
is  cleared  in  several  years,  or  in  one  year. 

Figs.  249  and  250  show  the  arrangement  of  the  age-classes 
in  a  forest  at  Sternberg,  in  Thuringia.  If  it  is  wished  to  fell 
the  70-year-old  wood  without  endangering  that  50  years  old, 
which  it  at  present  shelters  from  the  west  wind,  it  becomes 
necessary  to  separate  the  two  woods  by  a  severance- felling. 
This,  as  the  diagrams  show,  has  been  already  done  six  years 
ago,  when  the  strip  was  planted  with  -i-years-old  spruce  trans- 
plants, which  now  form  a  lO-year^old  protection  belt  to  the 
50-year-old  trees.  The  westerly  border-trees  of  the  latter, 
have  now  become  so  wind-firm  that  the  severance-felling  (/>) 
might  be  widened.  Another  severance-felling  (a)  has  also 
been  made  between  the  30  and  50-years-old  woods,  because 
the  latter  is  to  the  west  of  the  former  and  will  first  be  mature. 
The  proposed  widening  of  (a)  is  marked  in  Fig.  249  by  a  line, 
and  in  Fig.  250  by  shading,  but  it  cannot  be  carried  out  until 
the  younger  wood  has  become  more  wind-firm. 

There  is  no  apparent  necessity  for  the  severance-felling  (<■), 
as  the  woods  on  both  sides  of  it  are  of  the  same  age,  but  it 
has  been  cut,  in  order  that  the  large  50-years-old  wood  may 
be  divided  into  two  cutting  series,  both  beginning  from  the  east 
in  order  to  avoid  the  necessity  of  having  too  large  felling-areas. 

Indispensable  severance-fellings,  such  as  a  and  b,  are 
termed  protective,  whilst  those  like  c,  made  for  administrative 
reasons,  are  termed  silvicultural. 

Fig.  251  represents  a  normal  arrangement  of  age-classes  in 
a  forest,*  the  periodic  blocks  being  variously  shaded,  and  the 
compartments  drawn  square  instead  of  oblong,  so  as  to  take 
up  less  room.  The  white  compartments  are  the  youngest, 
forming  the  woods  of  the  fifth  period,  and  the  darkest  compart- 
ments are  those  of  the  first  period,  where  fellings  will  be  at 
once  commenced.  The  intermediate  shades  represent  the 
second,  third,  and  fourth  periodic  blocks. 

*  A  period  is  an  integral  part  of  a  rotation,  and  a  periodic  block  is  the  area  of 
forest  which  will  be  felled  during  any  periotl.  Thus  a  rotation  of  100  years 
may  be  divided  into  '>  periods  of  20  years  each,  and  a  working-section  of  a 
forest  into  five  periodic  blocks,  the  trees  in  which  are  aged  respectively  0 — 20, 
21—40,  41—60,  61-80,  and  81—100  years. 

N  N  2    . 


5i8 


PROTECTION    AflAIXST   WINDS. 


wt/^ 


Fig.  252. 
a  h  c  =  45  degrees. 

Denzin  has,  howevfir,  proposed  that  this  arrangement  of  rides 
parallel  and  perpendicular  to  the  storm-direction,  which  is  the 
one  usually  employed,  should  make  way  for  one  at  an  angle  of 


8T0RMS. 


549 


45  degrees  {a  h  c)  to  these  directions,  as  shown  in  Fig.  252. 
This  he  considers  to  afford  better  protection  to  woods  of  second 
period  against  south-west,  west-south-west,  and  south-south- 
west winds.  Borggreve  is  also  in  favour  of  this  system  of  rides. 
The  objection  to  this  arrangement  is  that,  although,  after 
the  dark  areas  have  been  felled,  the  woods  of  the  second  period 
are  better  protected  against  west  and  south-west  winds,  yet 
they  are  coiupletely  exposed  to  the  cutting  north-east  with  the 
accompanying  danger  from  rime. 


It  is  also  not  prudent  to  adopt  such  a  system  universally,  as 
storms  are  not  always  in  the  same  direction. 

Hess  thinks  that  further  experience  is  necessary  before 
deciding  between  these  two  arrangements,  and  also  as  regards 
the  shape  of  compartments,  whether  square,*  rectangular, 
parallelograms,  or  trapeziums,  as  this  may  also  affect  the 
amount  of  damage  done  by  storms. 

vii.  It  is  useless  leaving  standards  of  shallow-rooted  species, 
such  as  spruce,  in  exposed  places. 

viii.  Stumps  should  not  be  dug  up  in  preparatory  and  seeding 
fellings,  where  storms  are  to  be  feared.  After  storms  have 
damaged  valuable  middle-aged  woods,  further  damage  may  be 

*  The  question  of  the  direction  of  fellings  in  mountainous  districts,  and  of 
the  proper  shape  of  compartments,  is  discussed  in  detail  by  Karl  Heyer,  in  "  Der 
Waldbau,"  1878,  pp.  52  ct  mj. 


550  PROTECTION    AGAINST    WINDS. 

prevented  by  thinning  out  the  crowns  of  trees  left  standing  on 
the  exposed  sides  of  woods,  and  lading  their  roots  with  stones 
if  they  are  easily  procurable  (Fig.  253). 

5.   Treatment  of  IJliidfaUs  and   Wood-hreakafic. 

On  account  of  danger  from  bark-beetles,  which  follow 
extensive  breakage  in  a  wood,  prompt  measures  must  be  taken 
after  damage  has  been  done  by  a  storm. 

(a)  As  soon  as  possible,  using  all  available  labour,  and 
mechanical  means  (transportable  steam-saws,  etc.),  convert 
the  In-oken  material  and  remove  it  from  the  wood,  after 
stripping  the  bark  from  all  stems  and  broken  pieces,  at  any 
rate  of  conifers.  Trees  that  are  still  standing  obliquely,  or 
resting  against  other  trees,  can  be  left  till  the  following  season. 

{It)  All  wood  unfit  for  timber  should  be  split  and  the  stacks 
of  fuel  should  be  set  up  in  well-aerated  places.  All  rubbish 
may  be  made  into  charcoal  or  even  burned,  if  necessary. 

(f)  Stems  that  cannot  at  once  be  sold,  should  be  barked, 
to  prevent  insect-attacks.  Whether  they  should  be  completely, 
or  partially  barked  in  strips  depends  on  circumstances,  chiefly 
on  the  species  of  tree.  Complete  barking  is  the  best  protection 
against  insects,  but  it  favours  cracks  and  fungoidal  attacks. 
For  Scots  pine,  strip-barking  in  1894  gave  excellent  results. 
For  spruce  it  Is  best  to  bark  completely,  except  that  narrow 
rings  of  bark  may  be  left  at  the  ends  and  in  the  middle  of 
each  log. 

(d)  Stumps  and  roots  of  coniferous  trees  should  be  grubbed 
out  and  split  up,  even  if  a  pecuniary  loss  is  involved.  In 
broadleaved  woods,  on  the  contrary,  uprooted  stumps  should 
be  replaced  in  the  ground,  or  at  any  rate,  the  earth  knocked 
from  the  roots  and  the  holes  filled  up.  Ordinary  cart-jacks 
may  be  used  to  replace  the  stumps  ;  they  cost  about  456".  each, 
and  two  jacks  are  required  for  each  stump.  In  a  beech-wood, 
lifty-one  men  at  two  shillings  a  day  replaced  422  stumps  in 
this  way  at  a  cost  of  fourpence  a  stump. 

{(■)  Wherever  labour  is  insufficient  to  deal  with  all  the  fallen 
and  broken  wood,  the  trees  uprooted  with  balls  of  earth  may 
be  left  for  a  year. 

Such  trees,    if   broadleaved,   obtain   much    moisture   from 


STORMS.  551 

their  roots  and  may  even  put  out  foliage  for  two  years  in 
succession,  and  have  even  borne  mast.  Conifers  only  may  be 
attacked  by  beetles  and  the  wood  become  unsound  when  left 
in  this  way. 

When  the  stumps  are  sawn  off,  the  wood  above  the  saw-cut 
should  be  firmly  encircled  with  a  chain,  in  order  to  prevent 
splitting  of  the  log. 

(,/■)  Favourable  conditions  of  sale  should  be  offered  so  that 
all  broken  wood  may  be  sold  as  soon  as  possible.  All  intended 
fellings  should  be  postponed  until  the  volume  of  the  l)roken 
wood  has  been  calculated,  and  deducted  from  the  annual  yield. 
If  there  is  more  wood  broken  than  the  fixed  annual  yield,  all 
principal  fellings  should  be  postponed  for  a  year  or,  more. 

Some  idea  of  the  large  quantity  of  wood  which  is  blown 
down  may  be  gained  from  the  fact  that  in  the  spruce  and 
silver-fir  State  forests  in  Wiirttemberg,  about  one-third  of  the 
fixed  annual  yield  comes  from  windfalls  and  breakage. 

0.   Treatment  of  Woods  which  have  been  Damaged  by 
Storms. 

When  we  consider  the  great  variety  of  local  circumstances 
which  iiitiuence  the  degree  of  damage  done  by  storms,  it  is 
impossible  to  draw  up  special  rules  for  the  treatment  of  injured 
woods  which  will  meet  all  cases  that  may  occur. 

A  few  general  rules  will,  however,  be  given  which  are 
applicable  to  the  commoner  cases  for  trees  and  poles,  no 
damage  being  done  by  storms  to  thickets  of  saplings  or  to 
coppice-shoots.  Further  information  on  this  subject  should 
be  obtained  from  books  on  silviculture. 

A.  Injured  Trees. 

All  mature  or  nearly  mature  woods  that  have  been  badly 
invaded  by  storms  should  be  felled  earlier  than  was  otherwise 
intended  ;  this  is  especially  true  for  woods  which  have  thus 
become  full  of  blanks.  If,  however,  the  storm  has  caused 
only  a  few  blanks,  the  date  fixed  for  fellings  need  not  be 
anticipated. 

Small  blanks  due  to  the  fall  of  single  trees,  or  small  groups 
of  trees,   cannot  well  be  planted  up,  as  plantations  succeed 


55^  PROTFXTIOX    AGAINST    WINDS. 

badly  in  such  places,  and  within  ten  or  fifteen  years  the  crowns 
of  the  surrounding  trees  will  close  them  again.  Larger 
blanks,  however,  should  be  at  once  planted,  before  they 
become  covered  with  weeds,  unless  natural  regeneration  can 
be  secured.  In  planting  blanks,  about  20  to  25  feet  should 
be  left  unplanted  round  them,  as  plants  within  this  strip 
would  suffer  from  the  shade  of  the  surrounding  trees. 

In  filling  blanks  in  injured  spruce  and  silver-fir  woods, 
beech,  hornbeam,  sycamore,'  or  silver-fir  are  preferable ;  but 
if  the  forest  contains  red  deer,  silver-fir  plants  will  require 
fencing  with  hurdles.  "Woods  of  Scots  pine  and  larch,  when 
damaged  by  storms,  may  be  filled  up  with  spruce,  Weymouth 
or  Corsican  pines.  Beech  woods  that  have  been  invaded, 
where  the  soil  is  deep,  should  be  planted  with  oak,  and  on 
good  but  stony  soil,  with  sycamore  ;  in  wet  places,  with  ash, 
or  alder.  When  the  next  felling  takes  place,  these  groups  of 
young  trees  will  be  carried  on  for  another  rotation,  but  will  be 
thinned  and  pruned  where  they  endanger  the  future  young 
beech.     They  will  eventually  yield  fine  timber  trees. 

B.  Injured  Poles. 

It  is  very  difficult  to  decide  on  the  proper  treatment  of  pole- 
woods  when  broken  into  by  storms.  Premature  fellings  would 
be  undertaken  only  when  the  damage  done  is  on  a  large  scale, 
or  when  these  woods  interrupt  the  normal  cutting-series, 
or  when  they  would  not  expose  neighbouring  woods  to 
the  west. 

In  most  cases  the  felling  of  broken  poles  will  be  considered 
in  connection  with  the  volume  of  broken  timber  from  older 
compartments. 

In  general,  the  treatment  of  damaged  pole-woods  will  vary 
according  to  species,  locality,  area  of  blanks,  etc. 

Small  blanks  could  be  left  unplanted  for  the  same  reason  as 
that  given  for  older  woods.  Larger  blanks  could  be  planted 
with  tall  transplants  of  beech,  hornbeam,  or  sycamore.  Lime 
and  white  alder  are  also  suital)le  species.  Larch  and  Wey- 
mouth pine  owing  to  their  rapid  growth  would  soon  fill  up  the 
blanks,  but  the  larch  does  not    thrive    everywhere,  and  the 


STORMS. 


553 


Weymouth  pine  does  badly  in  mountainous  districts.  Here 
also  12  to  18  feet  interval  should  be  left  between  the  plantation 
and  the  still  standing  poles. 


"Woods  intended  for  natural  regeneration  may  be  trained 
up  by  means  of  heavy  thinnings  to  produce  seed  earlier 
than  usual. 


554 


CHAPTER   IV. 

PROTECTION    AGAINST    HEAVY    RAIN. 

1.  Dauiaiie  done. 

A.    General    Account. 

Heavy  and  prolonged  rainfall  and  occasionally  water-spouts 
damage  forests  by  carrying  away  the  dead  leaves,  the  soil,  and 
seeds ;  by  uprooting  young  plants,  the  roots  of  which  are  not 
sufficiently  developed,  such  as  seedlings  and  nursery  trans- 
plants recently  put  out ;  by  causing  local  swamps,  destroying 
roads  and  ditches,  loosening  the  roots  of  trees,  preventing 
fruit  from  ripening,  and  breaking  it  off. 

The  results  are  impoverishment  of  the  soil,  failure  of 
sowings,  blanks  in  plantations,  inundations,  liability  to  wind- 
fall, loss  of  seed,  etc. 

B.  Damage  under  Special  Conditions. 

The  conditions  on  which  the  extent  of  the  damage  de- 
pends, independently  of  the  force  and  volume  of  the  rain- 
fall, are  chiefly  the  age  of  the  crop,  and  the  nature  of  the 
localitij. 

Only  young  plants  the  roots  of  which  are  insufficiently 
developed  run  the  risk  of  being  uprooted.  These  are  chiefly 
young  germinating  seedlings,  and  transplants  just  lined  out  in 
nurseries,  or  planted  in  a  felling-area. 

As  regards  the  locality,  steep  slopes  with  loose  light  soil, 
which  are  neither  covered  with  woody  growth,  nor  with 
herbage,  moss  or  dead  leaves,  are  most  liable  to  damage. 
Loose  soil  when  saturated  with  rain  renders  the  roots  of  trees 


PROTECTION    AGAINST    HEAVY    RAIN.  555 

less  secure  against  windfall.  Clay  soils  are  also  injuriously 
affected  by  heavy  rains,  as  a  crust  forms  on  their  surface 
excluding  air  from  the  roots  of  plants. 


2.  Protective  Rules. 

(a)  Maintain  the  forest  growth  and  natural  soil-covering  of 
herbage,  moss,  and  dead  leaves  on  all  steep  slopes  exposed  to 
denudation. 

In  high  forest,  it  is  best  to  have  natural  regeneration 
under  a  shelterwood,  but  on  slopes,  coppice  is  less  heavy 
than  high  forest,  and  protects  the  soil  as  well.  In  plant- 
ing up  such  localities,  the  slopes  may  be  terraced  with 
advantage,  and  planting,  which  is  preferable  to  sowing, 
should  be  in  horizontal  lines  commencing  at  the  top  of  the 
slope.  For  dry  calcareous  slopes  the  Austrian  pine  is  most 
suitable. 

(h)  Establish  a  system  of  horizontal  leaf-catching  trenches, 
or  -protective  trenches  on  dry  slopes. 

These  trenches  differ  from  one  another  by  their  dimensions. 

The  protective  trenches  are  from  10  to  12  inches  deep  and 
25  to  33  feet  apart  ;  they  should  be  in  lengths  of  12  to  30  feet, 
to  prevent  the  formation  of  drains.  These  trenches  retain 
the  excess  water  after  heavy  rain,  and  part  with  it  gradu- 
ally to  the  soil,  the  permanent  moisture  of  which  is  increased. 
Leaves  are  washed  and  blown  into  them  and  the  soil  is 
thus  enriched  with  humus  and  rendered  more  porous  and 
deeper.  In  oak  and  beech  forests,  they  catch  the  acorns 
and  beech-nuts  which  are  rolling  downhill,  and  thus  natural 
regeneration  may  be  secured.  Even  the  spoil-heaps  from 
the  trenches  afford  suitable  sites  for  the  germination  of 
seeds. 

If,  however,  the  trenches  are  intended  merely  as  leaf-catchers, 
they  are  shallower  and  closer  to  one  another  than  the  protec- 
tive trenches.  Excellent  results  have  been  obtained  in  the 
Hessian  district,  Lindenfels,  by  the  use  of  leaf-catching  trenches. 
They  cost  about  9(/.  to  Is.  per  running  meter. 

(c)  All  measures  which  cause  or  favour  loosening  of  the 
soil    should    ho    abandoned    in    steep  places ;    these    are : — 


556 


PROTECTION    AOATNS'l'    HEAVY    RAIN. 


extraction  of  stumps,  pasturing  cattle,    trenching   the   soil, 
removal  of  litter,  etc. 

id)  In  order  to  protect  forest  roads  from  the  effects  of 
violent  rainfall,  ditches  and  culverts  should  he  constantly 
kept  free  from  weeds,  silt  and  dead  leaves.     Where  the  road 


Fi-    2o.J.— JlailstoiK.'s  (natural  size)  tliat  IVll  at  Seafonl  ou  May  oOth,  18'J 
From  a  photo  by  "Wynttr,  Seafonl. 


passes  through  a  sandy  cutting,  the  banks  on  either  side 
may  be  terraced  and  fixed  by  wattle-work  fencing,  stakes  of 
living  willows  being  used,  and  sand-fixing  species  planted 
between  the  fences. 


557 


CHAPTER  V. 

PROTECTION    AGAINST    HAIL.* 

1.  Daiitaf/c  done. 
A.  General  Account. 

Hail  completely  beats  down  young  plants,  and  injures  sap- 
lings, poles  and  young  trees  by  breaking  off  leaves,  blossom, 
fruits,  young  twigs,  and  leading  slioots,  and  by  stripping  off 
flakes  of  bark,  eitber  in  little  patches  or  short  strips,  and  thus 
exposing  the  cambium-zone.  The  marks  of  the  wounds  made 
by  hail  in  the  bark  of  trees  are  often  noticeable  for  a  long 
time,  the  amount  of  damage  done  depending  on  the  size  of  the 
hailstones. 

Birds,  and  game  such  as  hares  and  roes,  may  be  killed  by 
large  hailstones.  The  greater  the  size  of  the  latter  the  greater 
the  damage  done. 

The  direct  consequences  of  damage  by  hail  are  :  loss  of  incre- 
ment, disease,  deformed  growth,  decreased  production  of  seed, 
and  even  death  of  young  plants  and  poles. 

The  indirect  damape  consists  in  insect  attack  and  the  admis- 
sion through  the  wounds  made  by  hail  of  spores  of  species  of 
Nectria  and  other  fungi. 

B.  Damage  under  Special  Conditions. 

Conifers  suffer  most  from  hail,  especially  the  Scots,  Austrian 
and  "Weymouth  pines,  the  spruce  and  silver-fir  somewhat  less ; 
the  larch  soon  recovers  from  injuries  to  its  shoots  or  bark. 

Among  broadleaved  species,  those  with  less  power  of 
occluding  wounds,  and  with  thin  bark,  such  as  the  beech, 
suffer  most,  but  the  oak,  robinia  and  other  trees  when  young 

*  Iliiiikcr,  Hans:  "Die  Hagcschliige  in  Kanton  Aargau."  Berlin,  1881. 
'•  Jlittheilungen  des  Vernischen  Statistischen  Bureaux."  Bern,  1885,  1886 
"  Die  hagclschlagc  seit,'  1878. 


55S  PROTECTION    AOAINST   HAIL. 

may  be  seriously  injured  ;  the  birch  owing  to  its  elastic  shoots 
and  leathery  bark  does  not  suffer  much  from  hail. 

Young  plants  1  to  15  years  old  are  most  endangered,  year- 
lings being  often  destroyed  by  a  hailstorm  ;  and  sowings, 
especially  when  on  a  large  scale,  suffer  more  tlian  jilantations. 
Poles  15  to  BO  years  old  suffer  less  than  younger  plants,  while 
serious  damage  is  rarely  done  to  trees  over  30  years  old.  The 
later  in  the  spring  the  hail  occurs,  the  greater  is  the  damage, 
especially  to  smooth-barked,  weakly  plants. 

Oak-coppice  for  bark  and  osier-beds  may  suffer  severely 
from  hail.  The  damaged  oak  shoots  are  difficult  to  peel,  and 
the  osier  wands  break  at  the  injured  points.  Even  coppice- 
with-standards  may  often  suffer  severely.  In  high  forest, 
open  woods  suffer  more  than  dense  woods,  and  isolated 
trees  and  those  along  the  borders  of  the  forest  suffer  most. 
"Westerly,  south-westerly  and  north-westerly  aspects  are  chiefly 
threatened,  as  hail  usually  falls  with  a  west  or  south-west 
wind.     The  stronger  the  wind,  the  greater  the  damage. 

2.  Prevalence  oj  Ilailstnnns. 

Hailstorms  are  not  very  common  in  Europe,  they  occur 
only  in  late  spring  or  summer  and  generally  during  the  day- 
time. They  are  very  severe  in  Northern  India,  occurring 
generally  during  April  and  May,  and  the  stones  are  then 
frequently  as  large  as  walnuts,  and  batter  stucco  buildings  as 
if  they  had  been  subjected  to  a  volley  of  musketry  and  even 
penetrate  corrugated  iron  roofs.  Such  hailstorms  may  com- 
pletely strip  the  young  shoots  from  trees  and  tea-bushes,  in 
the  latter  case  causing  damage  which  may  be  estimated  at 
thousands  of  pounds  for  a  tea  district. 

In  Germany  there  are,  on  the  average,  only  about  five  hail- 
storms a  year,  but  on  the  west  coast  of  Europe  there  are 
about  fifteen.  These  are  sometimes  very  local,  extending 
only  over  small  areas.  Thus,  in  Cambridgeshire,  within  fifteen 
miles  round  Chatteris,  one  shilling  per  acre  insurance  for 
agricultural  crops  against  hail  is  charged ;  outside  this  zone, 
sixpence  per  acre. 

Hailstorms  are  very  prevalent  in  "Wiirttemberg,  where 
thousands  of  acres  of  cultivated  land  are  annually  laid  waste 


PROTECTION    AGAINST    HAIL.  559 

by  hail ;  a  record  of  them  has  been  kept  since  1828.  The 
chief  results  of  the  statistics  there  recorded  may  be  summarised 
as  follows  : — 

Communes  ^Yith  fields  on  hill-sides  with  south-westerly, 
westerly  and  north-westerly  aspects  suffer  most.  East,  south- 
east and  north-east  aspects  suffer  much  less. 

Hailstorms  generally  come  with  the  S.S.W.,  W.  and  W.S.W. 
winds.  They  follow  the  course  of  large  river- valleys,  when 
these  run  N.E.,  but  leave  the  valleys  when  they  run  in  other 
directions. 

No  connection  between  systems  of  forest-management,  nor 
species  of  trees  grown  is  discernible,  either  on  the  severity  or 
frequency  of  the  hailstorms. 

Observations  have  also  been  made  at  the  Meteorological  Office 
at  Zurich  in  Switzerland,  between  1883  and  1893,  and  in  dis- 
cussing these.  Dr.  C.  Hess*  states  that  hail  is  more  frequent 
in  valleys  than  on  mountains,  where  it  is  often  transformed 
into  sleet  or  rain.  Near  marshes  and  lakes,  hail  is  more 
frequent  than  over  woods.  On  passing  over  cultivated  lands 
or  hill  forests,  there  is  a  tendency  to  a  decrease  in  the  intensity 
and  at  times  an  entire  cessation  of  the  hailstorms.  Hailstorms 
follow  a  regular  line  and  maps  could  be  constructed  showing 
where  the  crests  of  the  hills  should  l)e  protected  by  forests. 

A  hailstorm  most  destructive  to  woodlands  occurred  on  the 
2nd  of  August,  1888  at  Chybi,  in  Austrian  Silesia.  On  1,917 
acres  of  forest,  belonging  to  the  Archduke  Albrecht,  three 
confluent  hailstorms  almost  completely  destroyed  500  acres  of 
young  woods  and  plantations,  and  injured  800  acres  of  poles, 
middle-aged  and  old  woods  to  such  an  extent  that  they  had  to 
be  felled. 

Mr.  Rebmann,  forstmeister  at  Strassburg,  describes  the 
great  damage  done  by  a  hailstorm  on  the  30th  June,  1898, 
which  crossed  Alsace  from  Avricourt  in  France,  past  Worth 
to  Karlsruhe  into  Bavaria.  The  storm  travelled  at  34  miles 
an  hour  over  a  distance  of  437  miles,  lightning  being  almost 
continuous.  The  stones  were  sometimes  as  large  as  the  fist 
and  killed  much  game  and  birds,  one  man  and  two  horses. 

*  Extract  from  '^Nature,"  January  .3,  189.",.  Translated  from  "  Naturwis- 
scnschaftlich  Wochcnschrift"  for  December  9,  1894. 


560  PROTECTIOX    AOAINST    TIATL. 

About  3,500,000  cubic  feet  of  old  timber  was  broken  and  thrown 
down,  besides  great  damage  done  to  young  wood  and  to  the 
agricultural  crops.  Tbe  falling  of  such  masses  of  hail  caused 
the  air  to  rush  in  all  directions,  and  trees  were  consequently 
blown  down  from  all  points  of  the  compass. 

According  to  Claudot("Eev.  des  E.  et  F.,"  10th  March,  1890) 
French  official  statistics  give  27,000,000  francs  as  the  average 
value  of  the  annual  damage  done  by  hail  to  French  crops  in 
1825-36,  whilst  in  1884-88,  this  damage  averaged  105,000,000 
francs,  so  that  insurance  rates  against  hail  have  increased  so 
as  to  become  sometimes  prohibitive. 

Owing  to  the  disastrous  effects  of  hail  on  agriculture,  the 
question  whether  the  maintenance  of  woods  on  mountains 
and  hills  affects  the  prevalence  and  severity  of  hailstorms  is 
highly  important.  It  is  found  that  in  Canton  Aargau,  in 
Switzerland,  districts  with  much  woodland  suffer  less  from  hail 
than  less  wooded  districts. 

District. 

Zosingen 
Lenzburg 
Muri 

In  the  northern  part  of  this  canton,  the  hailstorms  prevail 
in  the  badly  wooded  tracts,  and  are  scarcely  known  in  the 
well  wooded  ones.  In  Bohemia,  however,  observation  has 
not  supported  any  connection  between  woodland  and  hail. 

3.  Protective  Measures. 

i.  All  hill-tops  and  ridges  should  be  wooded  and  all  l)lanks 
in  forests  should  be  filled  with  strong  transplants. 

ii.  Adopt  selection  fellings  in  districts  subject  to  hail- 
storms. 

iii.  Mix  broadleaved  trees  with  conifers,  so  that  if  the 
latter  are  seriously  injured  there  may  still  be  left  material  to 
restock  the  woods. 

iv.  Seriously  injured  spruce  and  Scots  pine  are  ruined  and 
must  be  felled.  With  larch  and  silver-fir  recovery  is  possible. 
Young  broadleaved  plants  should  be  cut  back  and  allowed  to 
shoot  up  again. 


Woo-lland 
per  cent. 

40 

Hailstorms 
annually', 

2 

32 

6 

19 

-       10 

56] 


CHAriEli  VL 

PROTECTION    AGAINST    SNOW. 

1.   I)ama<ie  done. 
A.   General  Account. 

Snow  injures  forest  plants  by  its  dowiucanl  pressare  when 
lying  on  their  branches. 

The  resulting  damage  consists  either  in  snow-pressure  or 
snoichreak. 

The  action  of  snow-pressure  consists  in  the  bending  or 
uprooting  of  entire  stems,  often  with  the  ball  of  earth  round 
their  roots,  or  branches  may  be  torn  out  of  the  stem. 

Snowhreak  is  said  to  occur  when  the  stem  or  branches  yield 
to  the  weight  of  snow  accumulated  on  them  and  break,  either 
across  the  bole,  the  crown,  or  branches.  When  the  ground 
is  soft,  bending  chiefly  occurs,  when  it  is  frozen  breakage. 

A  special  form  of  injury  arises  when  a  mass  of  snow  sliding 
down  a  hill-side  falls  on  undergrowth  and  crushes  it ;  this 
resembles  an  avalanche,  and  is  not  uncommon  on  cold  aspects. 

B.  Damage  under  Special  Conditions. 

The  direct  results  of  excessive  snowfall  resemble  those 
occasioned  by  storms  (p.  533).  Much  game  is  also  destroyed. 
Fortunately  rabbits  cannot  thrive  in  snowy  mountains,  as 
in  the  higher  Ardennes. 

The  indirect  damage  done  by  snow  is  the  softening  of  the 
soil  and  predisposition  to  denudation  and  landslips ;  swelling 
of  mountain  torrents,  owing  to  rapid  melting  of  snow,  causes 
disastrous  floods. 

a.  Species  of  Tree. 

Trees  with  pendulous  or  flexible  leaders  or  branches,  such 
as  birch,  larch,  deodar,  and  others  with  a  tendency  to  a  squat 
shrub-like  habit  and  to  form  side-shoots  into  leaders,  such  as 
the  mountain-pine,  green  alder,  and  most  rhododendrons,  are 

F.P.  0  0 


562  PROTECTION    AGAINST    SNOW. 

adapted  to  grow  in  regions  where  much  snow  falls  annually. 
On  the  coutrar}^  trees  with  brittle  attachment  of  the  branches 
to  the  stem,  such  as  Piinis  ruj'ula,  Mill,  and  some  Eucalypti, 
may  withstand  frost,  but  are  broken  to  pieces  by  the  snow. 

Most  European  trees  withstand  snow  fairly  well,  but  ever- 
green conifers  suffer  most  from  it,  in  the  following  order : — 
Austrian  and  Scots  pines  and  spruce ;  less — silver-lir. 

Weymouth  pine  resists  snow  well,  owing  to  the  elasticity  of 
its  branches,  and  the  larch  suffers  much  less  from  snow  than 
other  conifers  owing  to  its  having  no  needles  in  winter  fur 
snow  to  rest  on,  but  it  may  be  injured  when  snow  falls  in 
autumn  before  it  has  lost  its  needles.  Cembran  pine  is 
another  tree  found  at  high  altitudes  ;  though  growing  slowly, 
it  attains  a  great  age,  and  resists  the  snow  owing  to  its  tufted 
foliage  and  tendency  to  form  new  leaders,  which  the  silver-fir 
also  possesses. 

The  Austrian  pine  does  nut  resist  snow  well  owing  to  its 
dense  crop  of  long  needles,  which  allow  much  snow  to  rest  on 
its  crown.  The  spruce  generally  suffers  more  than  Scots  pine, 
as  it  grows  at  altitudes  and  on  aspects  where  snow  is  most 
frequent  and  least  liable  to  thaw ;  the  Scots  pine,  on  the  other 
hand,  is  chiefly  grown  in  plains  where  snow  is  less  frequent 
and  thaws  sooner  and  cannot  therefore  accumulate  in  masses 
on  the  crowns  of  the  trees.  Wherever  the  spruce  and  Scots 
pine  grow  together  in  mixed  woods,  it  is  found  that  the  latter 
is  less  resisting  owing  to  the  brittle  nature  of  its  wood  ;  the 
branches  of  the  spruce,  being  more  elastic  and  splitting  less 
readily,  can  support  a  greater  weight  of  snow  than  pines.  The 
silver-tir  is  more  resisting  than  the  spruce,  owing  to  the  greater 
depth  of  its  root-system  and  the  more  upward  insertion  of  its 
branches.  In  Windsor  Forest,  after  a  heavy  snowfall,  the 
position  of  any  cluster  pine  can  be  at  once  recognised  by  the 
heap  of  broken  branches  under  the  tree. 

Among  hroadlcavcd  trees,  the  beech  suffers  most  from  snow, 
not  on  account  of  its  possessing  less  powers  of  resistance,  but 
because  it  ascends  higher  in  mountains  than  other  important 
broadleaved  species. 

Alder,  robinia,  aspen,  and  c.rack-willow  suffer  on  account  of 
their  brittle  branches,  luid  even  the  birch  is  broken  badly  if 


SNOWBREAK. 


563 


snow   should  fall  before  it  has  lost  its  leaves.      Hornbeam 

stands  the  danger  better,  and  so  do  ash,  maples  and  oak. 

It  is,  however,  more  difficult  to  draw  up  a  scale  of  broadleaved 

trees    according    to    their    powers    of 

resisting  spow,  as  so  few  broadleaved 

trees     form    woods     in     mountainous 

districts. 

The  lower  part  of  stems  growing  on 
mountain  slopes  exposed  to  heavy 
snowfall  curves  outwards  before  be- 
coming vertical  owing  to  the  pressure* 
of  the  snow  which  accumulates  behind 
it,  especially  during  the  youth  of  the 
tree.  In  hollow  depressions  on  steep 
slopes,  the  weight  of  the  descending 
snow  is  so  great,  that  masses  of  it  slide 
down  every  year  and  crush  all  the 
seedlings  they  meet.  Such  places  in 
the  Himalayas  are  bordered  by  species 
of  maple  and  horse-chestnut  which 
apparently  withstand  the  sliding  action 
of  the  snow  better  than  conifers  or 
evergreen  oaks,  which  are  the  chief 
components  of  the  Hitnalayan  forests 
between  7,000  and  U,000  feet  altitude. 


b.  Pari  (if  Tree. 

Young  trees  may  be  bent  down,  by 
snow,  individually  or  in  masses,  inclu- 
sive or  exclusive  of  the  ball  of  earth 
around  their  roots. 

Tearing  out  of  branches  by  wet  snow 
from  the  stem,  as  shown  in  Fig.  256, 
is  a  less  common  form  of  damage,  by 
which  the  stem  becomes  almost  worth- 
less for  timber,  and  more  liable  to  fresh 
breakage.  If  all  the  branches  of  a 
verticil  are  thus  torn  out,  the  leading 
shoot   invariably  dies.      This  form   of 


II 


Fig.  256.  —  ]*ortioii  of 
the  leadiug  shoot  of  u 
spruce,  six  branches  of 
which  have  been  torn  off 
by  snow. 

0  O  2 


1 64 


PROTECTION    AGAINST    SNOW 


injury  is  common  with  pines,  and  branches  up  to  2 J  inches 
thick  are  thus  torn  out,  the  holes  becoming  filled  with  resin, 
and  the  torn  branches  eventually  falling  off,  so  that  the 
damage  done  to  the  tree  may  escape  notice.  In  the  case  of 
spruce,  the  branches  thus  torn  out  are  not  generally  more 
than  11  inches  thick. 

Amongst  broadleaved  species,  softwoods,  including  birch, 
suffer  most  in  this  way,  then  ash  and  maples  ;  beech  and  oaks 
suffer  less,  though  much  similar  damage  was  done  by  snow  to 
oaks  in  "Windsor  Forest  in  October,  1878,  when  they  were  in 
full  leaf. 

According  to  the  age  of  woods  so  affected,  sometimes  the 
leaders  and  branches,  at  others  the  stem  at  different  heights 
above  the  ground,  are  more  subject  to  snowbreak. 

The  former  mode  of  injury  is  commonest  in  seed-years 
among  older  conifers,  as  the  cones  increase  the  weight  on  the 
crown  of  the  tree. 

Stem-breakage  usually  occurs  in  the  case  of  trees  injured  by 
resin-tapping,  game,  or  by  other  causes,  or  trees  which  are 
forked  or  cankered  at  or  above  the  seat  of  injury.  The 
exuding  resin  and  the  usual  local  decay  at  the  w^ound 
reduces  more  or  less  the  elasticity  and  strength  of  the 
stems.  Observations  in  the  Harz  show  the  influence  of 
wounds  on  snowbreak  most  clearly  up  to  an  age  of  about 
45  years.  Even  thinnings  have  an  influence,  as  most 
stem  breakage  at  wounds  occurred  in  heavily  thinned 
woods.  Thus  the  percentage  of  broken  stems  in  the  Harz, 
as  counted  by  von  Hague  (1859-GO),  in  32-year-old 
spruce  poles  injured  by  game  and  resin-tappers,  is  as 
follows  : — 

BuKAKACK  OF  Stems. 


At  the 
lioiiit  of  inj\iry. 

Above  tlie 
su.it  of  injury. 

Remarks. 

73 
75 

88 

27 
2."> 
12 

Unthinned  wood. 

Slightly  tliiniied  .1  year  before. 

Heavily  thinned  a  year  before. 

SXOWBREAK. 


565 


The  following  table  gives  von  Seelen's  ol)servations  on 
damage  by  snow  in  December,  1883,  in  the  Hasselfeld  forest 
range. 


Place  of  Breakage. 

PEROENTAdE   OF 

Breakaoe. 

Remarks. 

30-40-year, 
old  trees. 

Over  40 
years  old. 

Root-collum 

0  feet  up  the  stem    

(Of  these  at  .i  place  where 
bark  was  injured) 

Over  6  feet  up  stem  to  crown 

Within  the  crown     

6 
02 

(00) 
20 
12 

17 
3 

(1) 
30 
50 

Altitude  1,800  feet, 
site  nearly  level.   The 
younger     wood     had 
been  heavily  thinnetl. 
1 ,080      stems      were 
counted. 

r.  Sijstem  of  Manafjemenl. 

As  the  species  which  suffer  most  from  snow  are  grown  in 
high  forest,  that  system  is  most  liable  to  snowbreak. 

Woods,  where  the  trees  in  each  compartment  are  of  even 
age  and  height,  suffer  more  than  uneven-aged  woods,  such  as 
those  grown  under  the  selection  system  ;  in  the  former  case, 
snow  may  lie  in  masses  liSe  a  flat  roof  over  the  crowns  of  the 
trees,  especially  when  the  wood  is  densely  stocked,  whilst  in 
uneven-aged  woods  the  snow  has  a  greater  surface  to  cover, 
the  tree-tops  being  irregular  in  height,  and  more  snow  reaches 
the  ground  by  falling  between  the  crowns  of  the  trees.  In  the 
second  case,  the  wind  also  enters  the  wood  more  freely  and 
shakes  the  snow  from  the  crowns  of  the  trees. 

Hence,  in  localities  liable  to  snowbreak,  the  selection  and 
group  systems  are  more  suitable  than  other  high  forest 
systems.  In  coppice-with-standards,  the  lanky  tellers  occa- 
sionally suffer  soon  after  a  felling.  Pure  coppice  is  rarely 
injured  by  snow. 

(I.  A(je  of  Wood. 

Slowly  growing  species  such  as  silver-fir,  spruce  and  beech 
are  most  endangered  by  snow  between  the  ages  of  20  and  60 
years,  quickly  growing  species  such  as  Scots  pine  and  larch 


566  I'ROTKCTION    AfJATNST    SNOW. 

between  the  a^es  of  15  and  30  years.  Thickets  1  to  20  j^ears 
old  withstand  snow  better  owing  to  their  elasticity,  and  woods 
over  GO  years  old  snlTer  less,  on  account  of  the  greater  size  of 
the  trees,  although  in  Thuringia  60  to  lOO-year-old  woods 
have  suffered  severely.  A  distinction  must,  however,  be 
made  between  bending  and  breakage.  Bending  owing  to  snow 
is  most  frequent  in  woods  20  to  40  years  old,  and  occurs 
generally  in  patches. 

Snowbreak,  on  the  contrary,  is  most  frequent  in  woods 
40  to  GO  years  old  and  even  in  older  woods.  The  crown  and 
leading  sligots  of  the  trees  are  chiefly  broken  in  woods  up  to 
GO  years  old,  whilst  in  older  woods  branches  are  brdlcen  off  the 
stem.  In  otherwise  uninjured  woods,  stem-breakage  is 
generally  near  the  base  of  the  crown  and  occurs  here  and  there 
to  individual  trees.  Younger  drawn -up  stems  are  often  broken 
in  groups,  and  sometimes  hi  strips,  owing  to  the  action  of 
wind  during  or  after  the  fall  of  snow. 

In  the  extensive  snowbreak  which  happened  in  the  Harz 
forests  in  December,  1883,  trees  of  the  following  categories 
were  injured  in 'following  proportion  for  the  whole  area 
affected : — 

Percentage  of 
ISrcakagc. 

10 
25 
25 
20 
12 
5 
3 

c.  Locidihj. 
Mountain-forests  are  more  affected  by  snowbreak  than 
forests  of  the  plains  and  lowlands.  The  localities  in  Germany 
most  exposed  to  snowbreak  lie  between  altitudes  of  1,300  and 
2,400  feet ;  the  snow  falls  more  abundantly  at  higher  eleva- 
tions, but  then  the  flakes  are  smaller  and  drier,  and  do  not 
become  so  readily  attached  to  the  trees;  lower  down,  on  the 
other  hand,  the  fall  of  snow  frequently  changes  into  rain.     In 


Age  of  Woods 
in  Years. 

20- 

-30     . 

80- 

-40     . 

40- 

-50     . 

50- 

-GO     . 

60- 

-70     . 

7.0- 

-80     . 

80; 

and  over 

SNOWBREAK.  567 

Switzerland,  in  1885  damage  by  snow  extended  to  an  altitude 
of  G,560  feet  above  sea-level. 

No  aspect  is  absolutely  safe  against  snowbreak ;  most 
snow  in  Central  Europe  comes  from  a  westerly  direction,  fi'om 
which  quarter  also  the  strongest  winds  blow.  The  south- 
easterly, easterly  and  north-easterly  aspects,  especially  just 
below' the  crest  of  the  hills,  suffer  most;  the  snow  falling 
most  abundantly  in  such  places  and  l^eing  less  easily  shaken 
from  the  trees  by  the  wind,  accumulates  on  their  crow'ns. 
Since,  also,  freezing  winds  blow  chiefly  from  the  east,  a  frozen 
crust  is  tl^en  formed  over  the  snow,  on  which  liiore  snow 
lodges  when  there  is  a  subsequent  snow-storm.  North  and 
north-westerly  aspects  suffer  less,  and  westerly,  south-westerly 
and  southerly  aspects  least  of  all.  Depressions  and  sheltered 
spots  in  valleys  are  much  exposed  to  snowbreak,  as  the  wind 
cannot  free  the  crowns  of  the  trees  from  snow  in  such  places. 

Fertile,  deep,  moist  soil  (above  granite,  basalt,  porphyry) 
favours  growth  in  height,  produces  brittle  coniferous  wood, 
and  disposes  the  trees  to  breakage.  Slowly  ^rown  short  trees, 
that  occur  in  unfavourable  localities,  are  much  less  endangered. 
Too  much  moisture  in  the  soil  is  also  unfavourable,  as  the 
roots  have  a  bad  hold  on  the  ground. 

A  strong  growth  of  gra^s  and  herbage  is  bad  in  plantations, 
as  the  snow  presses  the  weeds  on  the  young  plants. 


/.  Mode  of  Formation. 

Under  otherwise  equal  conditions  young  pole-woods  which 
have  grown  up  in  dense  thickets  suffer  most  from  snow%  their 
scanty  root-systems  and  slender  drawn-up  stems  exposing 
them  to  danger.  Poles  resulting  from  sowings  suffer  more 
than  plantations  where  from  the  first  each  individual  plant 
has  had  sufficient  room  for  its  development.  Planting  two  or 
more  plants  in  each  planting  spot,  termed  multiple-planting, 
is  also  less  favourable  where  snow  is  to  be  feared  than  planting 
single  plants. 

The  distance  between  the  planting-spots  is  also  important, 
as  plants  with  stronger  roots,  and  crowns,  capal)le  of  resisting 
the  pressure  of  the  .snow,  result  from  wide  planting.     Such 


56S  PROTECTION    AGAINST    SNOW. 

plants  may,  however,  be  uprooted,  at  least  at  high  altitudes, 
owing  to  the  large  surface  of  their  crowns,  so  that  wherever 
this  danger  is  to  be  feared  planting-spots  must  not  be  too  far 
apart. 

Observations  made  in  the  Harz  forests  in  December,  1883, 
after  the  disastrous  snow-storm  already  referred  to,  gave  the 
following  percentages  in  100  acres  of  spruce  woods  which  were 
bent  down  and  l)rolvon  by  the  snow : 

Single  planting,  18, 
Multiple  planting,  2G, 
so  that  the  single  planting  suffered  about  one-third^  less  than 
multiple  planting. 

Mixed  woods  consisting  of  broadleaved  trees  and  conifers 
suffer  less  than  pure  coniferous  woods,  as  less  snow  rests  on 
the  trees,  and  the  broadleaved  species  are  less  liable  to  injury. 
Beech,  sycamore  and  hornbeam  should  therefore  be  mixed 
with  spruce  or  silver-fir.  The  larch  has  not  succeeded  in 
German  mountain-forests,  but  it  grows  admirably  in  the 
British  Isles  when^  mixed  with  beech  and  other  conifers,  pro- 
vided the  soil  is  suitable,  and  such  mixtures  are  well  adapted 
to  withstand  heavy  falls  of  snow. 

[1.  Effect  of  Thiniwigs. 

Woods  which  have  been  properly  thinned  are  generally  less 
liable  to  damage  than  unthinned  woods,  not  only  on  account 
of  the  sturdier  forms  of  the  trees  and  their  more  regular 
crowns,  but  also  because  more  snow  reaches  the  ground  in 
thinned  woods,  and  the  weight  of  the  snow  which  rests  on  the 
crowns  of  the  trees  is  less  than  when  the  woods  are  very 
dense.  The  wind  is  also  more  effective  in  thinned  woods  in 
shaking  the  trees  free  from  snow. 

Extensive  snowbreak  has  indeed  been  observed  at  times  in 
thinned  woods,  but  this  does  not  invalidate  the  above  reason- 
ing, for  sometimes  thinnings  are  put  off  too  long,  and  if 
excessive  snow  should  fall  on  weakly  stems  just  set  free  by 
a  strong  thinning,  it  is  evident  that  much  damage  may  be 
done.  It  is  therefore  to  a  certain  extent  an  affair  of  chance, 
as  regards  the  first  thinning  in  a  dense  thicket,  whether 
damage   by   snow   occurs   or   not,  but  the  longer  the  wood 


SNOWBREAK.  569 

escapes  damage  after  the  thinning  has  been  effected,  the  better 
it  will  resist  should  a  severe  snow-storm  occur. 

In  thinned  woods,  individual  stems  are  more  liable  to 
breakage,  whilst  in  unthinned  woods  whole  patches  of  poles 
may  be  crushed.  Biihler*  has  undertaken  some  very  interest- 
ing experiments  to  investigate  the  effects  of  thinning  on  snow- 
break.  They  show  that  heavy  thinnings  are  less  affected  by 
snow  than  hght  thinnings ;  it  is  not  the  dominant  poles  with 
regularly  shaped  crowns  that  are  so  much  endangered  by  the 
snow  as  the  badly  grown  poles  with  lop-sided  crowns,  and 
these  are  removed  in  heavy  thinnings  as  well  as  dead,  dying 
and  dominated  poles.  A  heavy  thinning  somewhat  interrupts 
the  leaf-canopy,  and  thus  allows  more  snow  to  reach  the 
ground  than  in  a  dense  pole-wood. 

h.  State  of  the.   Weather. 

The  snow  is  the  more  destructive  the  wetter  and  larger 
the  flakes  and  the  more  quietly  it  has  fallen.  Small  flakes 
pass  more  easily  between  the  branches  of  the  trees,  and  dry 
snow  is  more  easily  shaken  off'  them  by  the  wind  than  damp 
snow.  During  a  frost,  however,  wood  is  more  brittle,  and 
consequently  breakage  is  easier. 

The  greatest  damage  is  done  when  a  thaw  sets  in  after  a 
fall  of  snow,  and  is  followed  by  a  frost,  a  fresh  fall  of  snow 
and  a  strong  breeze.  Such  a  combination  of  circumstances 
will  cause  extensive  snow-breakage  in  woods  of  all  ages, 
whether  sown  or  planted,  thinned  or  unthinned,  forming  a  sad 
picture  of  devastation  for  the  forester,  who  sees  the  results  of 
his  care  at  once  nullified. 

2.  Record  of  Damar/e  done  hij  Snow. 

Snowbreak  being  of  a  local  nature  only,  the  occurrence  of 
serious  damage  in  the  Ilarz  mountains  maybe  cited.  ])uring 
the  sixty-six  years  ending  with  1897,  there  have  been  nineteen 
disastrous  years  of  snowbreak,  or  one  year  in  every  four,  the 
worst  of  which  were  as  follows  : — 

In  January  and  February,  1844,  in    Hanover,  two  million 

*  "  Schnecdiuck  u.  Diiioliforstungsgrad,"  "  riactisclior  Forstwirtli,"  1800. 
Nos.  3— fi. 


570  PROTKCTION    AOAINST    SXOW. 

stems  were  broken  by  snow,  over  05  per  cent,  of  wbich  were 
under  7  inches  in  diameter.  In  November  and  December, 
1875,  in  Brunswick,  0,734,000  cubic  feet  of  timber  were 
broken  l)y  snow  on  85,635  acres,  being  at  the  rate  of  78  cubic 
feet  per  acre,  al)0ut  half  the  fixed  annual  yield  of  the  forests. 
The  chief  dainage  was  done  on  the  northern  side  of  the 
mountains.  From  the  10th  to  the  13th  December,  1883,  and 
from  the  11th  to  the  27th  January,  1884,  22,500,000  cubic 
feet  of  timljer  were  broken  in  the  Hanoverian  Harz,  and  about 
7,000,000  cubic  feet  in  the  Brunswick  Slate  forests. 

In  the  winter  of  1894  95,  owing  to  the  very  lieavy  snowfall, 
much  game  was  killed  in  Obersteirmark.  On  an  area  of 
1,793  square  miles,  5,642  head  of  red-deer,  chamois,  and  roes 
perished,  being  about  15  per  cent,  of  the  stand  of  game, 
estimated  at  21  hep,d  per  square  mile. 

3.  Protective  Rules. 
Protective  rules  against  damage  to  forests  by  snow  should 
l)e  drawn  up,  either  on  the  principle  of  reducing  the  power  of 
attachment  of  the  snow  to  the  trees,  or  of  strengthening  the 
latter.  The  question  will  be  discussed  under  the  heads  of 
formation,  tending,  .and  utilisation  of  the  woods. 

a.  Formation  of  Woods. 
.  i.  Species  endangered  by  snow  should  not  be  planted 
in  snow  localities,  especially  in  pure  forests.  Scots  pine  is 
absolutely  out  of  place  in  regions  where  snow  lies  deep  in 
■winter.  The  chief  sj^ccies  here  should  be  the  spruce,  silver- 
fir,  or  larch. 

ii.  In  planting  spruce,  introduce  a  mixture  of  silver-fir, 
larch  and  broadleaved  trees,  such  as  beech  and  sycamore. 

iii.  Natural  regeneration,  especially  for  silver-fir  and  beech, 
and  also  for  spruce,  will  give  better  results  than  regular  plan- 
tations; it  produces  the  trees  in  groups  and  with  a  mixture  of 
broadleaved  species,  which  should  be  encouraged. 

iv.  Where  the  clear-cutting  system  is  followed,  strong 
nursery-trained  transplants  should  be  used  to  restock  the 
felling-areas,  the  plantations  being  made  in  lines  parallel  to 
the  direction  of  the  prevailing  wind,  so  that  the  snow  may 


SNOWBREAK.  571 

fall  between  the  plants.  The  plants  should  be  somewhat 
closely  planted  wherever  heavy  snow  is  to  be  feared,  so  that 
they  may  afford  one  another  mutual  support  against  the  snow. 

V.  Avoid  sowings  in  the  open,  planting  with  strong  trans- 
plants (no  multiple  planting)  and  that  have  not  been  too 
closely  lined  out  in  nurseries,  so  as  to  produce  strong, 
resisting  plants. 

It  is  better  to  plant  in  lines,  which  should  be  parallel  to 
the  direction  of  the  prevailing  wind,  so  that  snow  can  be 
driven  between  the  rows  of  plants.  At  lower  elevations 
the  rows  should  be  3|  to  5  feet  apart,  at  higher  elevations 
2^  to  3i  feet,  to  prevent  the  branches  being  torn  out.  The 
plants  may  be  2J  to  3^  feet  apart  in  the  rows.  Wider  planting 
has  given  bad  results  in  the  Harz. 

vi.  An  excessive  growth  of  grass,  bracken  or  other  weeds 
should  be  removed  from  young  growth,  as  it  may  be  pressed 
down  by  the  snow  over  the  plants  and  kill  them. 

h.  Protection  during  Thinnings. 

i.  The  most  efficient  measure  to  protect  woods  against 
snowbreak  is  to  make  timely  thinnings,  in  accordance  with 
sylviculttiral  rules,  and  suitable  to  the  circumstances  of  each 
case.  In  woods  endangered  by  snowbreak,  thinnings  should 
commence  early,  be  frequently  repeated,  and  increase  in 
intensity  with  the  age  of  the  trees.  At  the  same  time  great 
care  must  be  taken  in  the  first  thinning  of  densely  stocked 
pole-woods. 

ii.  All  injuries  to  the  bark  of  trees,  including  resin-tapping, 
must  be  avoided. 

iii.  In  specially  valuable  young  pole-woods,  the  snow  may 
be  shaken  from  the  trees ;  this  measure  was  successfully 
applied  to  10  to  20-year-old  Scots  pines  in  Wiirtteraberg  and 
Silesia  in  1868,  but  can  evidently  be  carried  out  only  on  a 
small  scale. 

r.  During  the  Principal  Fellings. 

i.  Felling  by  the  selection  or  group  methods  should  be 
followed  in  high  mountain  regions,  on  peaks  and  ridges,  as 
this  favours  uneven  heights  in  the  trees.  Uniform  covering 
of  the  crop  with  snow  is  thus  prevented. 


572  PROTECTION    AOAINS^T    SNOW. 

ii.  "Wherever  clear  cuttings  are  practised,  the  felling-areas 
shouklbe  of  small  extent,  so  that  areas  of  even-aged  wood 
should  not  be  too  extensive ;  several  series  of  felling-areas 
should  therefore  be  established. 

iii.  In  coppice-with-standards,  only  strong  tellers  should  be 
reserved. 

4.   Treat  incut  of  Injured  Woods. 

The  treatment  of  injured  woods  will  depend  on  their  age 
and  the  species  of  which  they  are  composed,  and  the  kind  of 
damage  they  have  experienced. 

If  extensive  damage  has  been  done  by  snow,  the  first  duty 
of  the  forester  is  to  remedy  matters  as  soon  as  possible;  in 
coniferous  woods  especially,  all  bent  and  broken  wood  should 
be  at  once  worked  up  and  sold.  Trees  on  which  three  or  four 
verticils  of  living  branches  have  been  spared  may  be  left 
standing,  after  carefully  pruning  off  their  broken  branches. 
Stems  which  have  been  bent  over  from  the  ground  may 
recover  their  erect  position  owing  to  then-  elasticity  and 
striving  towards  the  light,  and  in  any  case  they  assist  in 
keeping  the  soil  covered.  The  woodcutters,  who  are  removing 
l)roken  stems,  may  be  directed  to  set  the  bent  stems  upright, 
and,  if  necessary,  attach  them  by  string  or  wire  to  stems 
which  are  still  erect. 

For  the  rest,  the  treatment  depends  chiefly  on  the  species, 
the  age  of  the  injured  crop  and  the  extent  and  nature  of  the 
snowbreak. 

Young  coniferous  woods  which  have  been  broken  in  patches 
and  strips  should  be  replanted  with  large  transplants  of  beech, 
sycamore,  larch ;  spruce,  silver-fir,  or  Weymouth  pine  may 
also  be  used,  in  accordance  with  the  suitability  of  the  soil  for 
each  species.  Breakage  of  leaders  is  often  repaired  naturally 
by  formation  of  new  leaders,  by  Scots  pine  and  larch,  even 
though  it  may  for  long  be  recognised  by  doubhi  leaders, 
bayonet  leaders,  etc. 

Older  coniferous  woods,  when  greatly  thinned  by  snow- 
break,  should  be  underplanted ;  spruce-woods  with  beech  and 
silver-fir;  Scots  pine  woods  with  s})ruce  and  sessile  oak.  The 
remarks  (p.  551)  already  made  regarding  repairs  of  damage 
done  l)y  wind  are  also  applicable  here. 


SNOWBREAK. 


573 


Injured  broadleaved  woods,  especially  beech  pole- woods, 
may  be  repaired  by  cutting  back  the  bent  stems  at  heights 
of  12  to  18  feet  from  the  ground,  the  stems  being  bent 
straight.  In  case  of  very  serious  damage,  however,  the 
injured  woods,  if  not  too  old  for  reproduction  from  the  stool, 
must  be  cut  back  close  to  the  ground,  and  the  thinned  wood 
underplanted  with  beech  or  silver-fir.  In  order  to  fill  larger 
gaps  between  the  trees,  sessile  oak,  larch,  Weymouth  pine, 
white  alder  and  robinia  may  be  used,  the  two  latter  at  low 
altitudes. 

By  means  of  a  combination  of  all  these  plantings,  woods 
like  coppice-with-standards  will  result,  which,  owing  to  their 
unevenness  in'age,  height  and  rate  of  growth,  will  be  better 
aljle  to  withstand  future  falls  of  snow. 


I'i;,'. 


-Bcecli  hcut  by  suow.     Silihv.iild,  uear  Zurich. 


574 


CHAPTER   VIL 

PROTECTION   AGAINST  RIME,* 
A.   General  Account  of  Damage. 

EiME  and  ice  may  incrust  and  overlade  stems,  crowns  and 
branches,  and  thus  break  or  uproot  trees.  Eime,  unless 
accompanied  by  snow,  seldom  seriously  damages  trees,  but 
this  is  not  the  case  with  ice,  and  when  this  is  followed  by 
snow  and  a  stiff  gale,  forests  may  suffer  very  considerably. 

The  damage  done  resembles  that  effected  by  storms  and 
snow. 

B.  Damage  under  Special  Conditions. 
a.  Species. 

Coniferous  woods  suffer  more  than  broadleaved  woods. 
Scots  pine  and  other  pines  suffer  most,  then  spruce,  silver-fir 
and  larch.  If  larch  be  covered  with  needles,  it  may  suffer 
more  than  spruce. 

In  broadleaved  woods,  poplars,  willows,  alder  androbinia, 
on  account  of  their  brittle  wood,  are  most  endangered,  but  as 
these  trees  are  not  extensively  grown,  their  damage  is  not 
very  important.  The  beech,  on  account  of  its  dense  foliage, 
suffers  considerably.  Oaks  and  birch,  in  leaf,  also  suffer 
greatly. 

I).  A(je  of  Crop. 

Whilst  damage  by  snow  chiefly  affects  thickets  and  young 
pole-woods,  ice  and  rime  will  do  more  damage  to  middle-aged 
and  even  mature  woods.  Scots  pine  and  larch-woods  thirty  to 
sixty  years  old  and  beech-woods  from  forty  to  eighty  years 
are  most  liable  to  injury.  Pole- woods  are  generally  bent,  but 
may  be  sometimes  crushed  by  the  weight  of  ice  they  bear,  as 

*  Vide  "  Notes  oil  Hoar  Frost  "  :  C  B.  Plowright,  "Journal  of  E.  Hort,  Hoc." 
March,  18'Jl. 


GENERAL   ACCOUNT   OF   DAMACiE. 


575 


Fig.    258. — Oak   tree,    braucUcs   liokcu   by  riuie.      From  vol.  xiii.    "Journal   of 
li.  Hort.  Soc,"  "  Notes  on  Hoar  Frost,"  Plowright, 


if  by  a  gigantic  roller.  Older  trees  are  generally  broken  either 
in  their  boles,  leaders  or  branches.  Conifers  laden  with  cones 
suffer  most  from  breakage  of  leaders.  Old  oaks,  especially 
when  stag-headed,  have  their  branches  broken. 


576  PROTECTION    AOAINST    IHMK. 

r.  Ldidlih/. 
The  damage  done  by  rime  and  ice,  in  Central  and  Northern 
Germany,  chiefly  occurs  at  altitudes  between  1,600  and  2,000 
feet.-  In  South  Germany,  up  to  3,300  feet,  crops  suffer  the  more 
the  faster  their  growth  and  the  shorter  the  interval  since  the 
last  thinning.  The  wetter  the  soil  the  more  trees  are  up- 
rooted. Northerly,  north-easterly  and  easterly  aspects  suffer 
most,  especially  steep  slopes  and  depressions  exposed  to  the 
north-east   wind.      Woods   suffer   on   both   sides   of  valleys 

running  east  and  west,  whilst 
in  valleys  running  north  and 
south  only  the  east  aspect 
suffers. 

d.  Densitij  of  Crop. 
Isolated  trees  suffer  more 
from  rime  and  ice  than  trees 
growing  in  dense  woods,  as 
they  liave  a  larger  surface 
exposed,  and  this  applies  to 
avenue  trees,  seed-bearers  in 
regeneration  -  fellings  and 
standards  over  coppice,  and 
also  to  trees  along  tl;e  easterly 
,,.      ,.„     ,.    „      ,  o    ,  and   northerly  borders    of    a 

lig.    2.)'J.     rsewlles  ot    Scots  piue  •' 

eucrustLil  witii  kc.  wood,  or  of  an  exposed  felling- 

area.  Trees  afford  one  another 
mutual  protection  in  a  dense  wood.  At  the  same  time,  lofty 
poles  just  set  free  from  a  dense  growth  by  a  thiiniing  may 
suffer  considerably. 

e.  Weather. 
Most  damage  by  ice  occurs  in  January  and  February  ;  but 
trees  may  be  endangered  in  November  and  December.     North 
and  east  winds  specially  favour  ice-formation. 

C.  Record  of  Bad  Years. 

The  damage  done  by  rime  and  ice  as  well  as  by  snow  is  of  a 
local  nature,  and  in  the  Harz  mountains  there  were  thirteen 


GENERAL    ACCOUNT   OF    DAMAGE. 


577 


bad  years  between  1821 — 1897,  which  were  also  the  years   n 
which  much  snow-break  occurred. 

The  weight  of  ice  on  the  trees  is  sometimes  considerable, 
as  much  as  fifty  pounds  on  six  pounds  of  wood,  A  most 
destructive  ice-break  occurred  between  the  18th  and  25th  of 
November,  1858,  in  the  Spessart,  Odenw'ald,  part  of  the 
Bavarian  Palatinate  and  Ehenish  Prussia,  in  which  the  ice- 
crust  was  eighteen  to  twenty  times  the  thickness  of  the  wood  on 
which  it  rested.  In  the  Spessart,  2,750,000  cubic  feet  of  wood 
was  broken  ;  in  the  Odenwald,  nearly  2,000,000  cubic  feet ;  in 
the  State  forests  of  the  Palatinate,  11,000,000  cubic  feet  and 


Fig.  •2i')i). — Shoot  of  Scots  pine  covered  with  ice. 

about  half  as  much,  in  the  Communal  forests.  Observations 
showed  that  a  spruce  plant  3J  feet  high  had  to  support 
165  lbs.,  and  single  Scots  pine-needles,  over  half  an  ounce  of 
ice.  The  picturesque  forms  of  the  ice-encrustations  are  shown 
in  Figs.  259  and  2G0. 

In  France  and  Central  Germany,  from  the  22nd  to  the  21th 
of  January,  1879,  there  was  most  extensive  breakage  of  woods 
by  ice,  which  is  described  by  Janin  in  the  Revue  des  Deux 
Mondes.  In  certain  broadleaved  forests,  about  50  per  cent. 
of  the  stems  were  broken,  and  in  carefully  thinned  Scots  pine- 
woods,  70  per  cent.  In  the  forest  of  Fontainebleau,  about 
5,300,000  stacked  cubic  feet  of  wood  were  broken,  thin  twigs 
of  wood  and  telegraph  wires  being  encrusted  with  ice  to  a 

F.P.  V  V 


57 S  PROTKCTION    AC^AINST    RTMK. 

thickness  of  8  inches.  Living  hirks  were  found  frozen  to  the 
ground  by  their  feet  and  tails,  and  in  the  Champagne  district 
dead  partridges  were  picked  up  covered  with  ice. 

Great  damage  by  rime  to  elm  and  other  trees  is  described 
by  Plowright  as  having  occurred  in  Norfolk  on  Jan.  7th,  1889. 
(Fig.  258.) 

D.  Protective  Rules. 

(a)  Formation  of  strong  young  growth.  Where  danger 
from  rime  and  ice  is  feared,  the  Scots  pine  must  be  excluded 
or  mixed  with  other  species. 

(h)  Maintenance  of  the  leaf-canopy  even  in  old  woods. 
Heavy  thinnings  should  not  be  made  in  dense  pole-woods. 

(c)  Isolated  standards  should  not  be  reserved  in  high 
forests. 

(d)  A  protective  belt  should  be  maintained  on  the  north- 
eastern and  eastern  borders  of  woods. 

{e)  Wherever  danger  from  rime-frost  is  greater  than  from 
storms,  cuttings  should  be  made  in  w^oods  from  south-east  to 
north-west ;  the  south-westerly  gales  then  blow  along  merely 
the  face  of  the  felling-areas,  and  endanger  a  few  border-trees 
only.  The  correct  direction  for  felling-series  can  be  decided 
only  after  a  thorough  know^ledge  has  been  acquired  of  the 
configuration  of  the  ground  and  of  the  local  factors. 

E.  Treatment  of  Injured  Woods. 

Eeference  is  here  invited  to  Chapter  III.,  p.  557,  and 
Chapter  VI.,  p.  570,  dealing  with  woods  damaged  by  storms 
and  snow,  as  those  which  have  been  injured  by  ice  will  require 
similar  treatment. 


PART  V. 

PROTECTION   AGAINST    NON-ATMOSPHERIC   PHENOMENA. 


P  1'  "J 


581 


PKOTECTION   AGAINST   NON-ATMOSPHERIC 
PHENOMENA. 

Thk  chief  non-atmospheric  phenomena  to  which  forests  are 
exposed  are  sua)nps,  floods  and  torrents,  avahmcltes,  sin/ting 
sands  and  forest  fires.  Damage  to  woods  by  these  agencies 
will  now  be  described. 


582 


CHAPTER   I. 

PROTECTION     AGAINST     DAMAGE     BY     SWAMPS, 
FLOODS    AND    TORRENTS.* 

Water  acts  either  as  a  meteoric  phenomenon,  or  as  stagnant 
or  flowing  water  on  the  surface  of  the  ground,  or  in  the  soil  ; 
its  effects  are  partly  mechanical  and  partly  physiological. 

The  chief  mechanical  effects  consist  in  soil-denudation, 
landslips,  or  floods.  Physiological  damage  is  done  to  plant- 
life  and  to  the  soil  hy  stagnant  water  causing  bogs  and 
marshes.  Damage  to  forests  by  heavy  rain  has  already  been 
dealt  with  (p.  554). 

Section  I. — Soil-Denudation. 

1.  Descriptu))t. 

Soil-denudation  on  steep  slopes  may  be  due  either  to  suhsoil- 
icater,  surface-water,  or  to  mountain  torrents. 

Subsoil-water  or  surface-water  on  hill-sides  may  cause  land- 
slips, which  bring  down  the  soil  with  the  vegetation  growing  on 
it,  and  expose  the  subjacent  rock ;  this  may  occur  either  when 
the  slope  of  the  hill-side  is  excessive,  or  when  there  is  an 
impermeable  substratum  which  prevents  the  further  descent 
of  the  water  into  the  hill. 

Excavations  of  pits  or  quarries  at  the  base  of  a  hill  may 
have  a  similar  effect. 

Mountain  torrents  may  cause  soil-denudation,  or  form  ravines, 
by  deepening  their  beds  and  by  wearing  away  their  banks. 
The  latter  effect  occurs  chiefly  at  sharp  turns  in  the  course  of 
the  torrent,  when  one  bank  is  formed  of  rock  and  the  other 
of  loose  material.     The  force  of  the  water  increases  with  its 

*  Kraft,  Gustav.,  "  Beitrage  zur  foistl.  Wasserbaukuiule."     Hannover,  18('.2. 
Demontzey,  "  Etude  sur  Ics  Travaux  de  Keboisenient  et  de  Gazounement  des  • 
Montagnes."     Paris,  1878.     Id.  Traits- Pratique.  1882.     Von  Senkendorf, '•  Ver- 
bannungderWildbache."    Vienna,  lS8i.     Landolt, '•  Die  Biiche,  Schneulawiucn 
und  Steinschlage."     Ziirich,  1886. 


SOIL-DENUDATION.  583 

velocity,  and  ma.y  be  assumed  to  be  proportional  to  the  sixth 
power  of  the  velocity  of  the  stream. 

To  cite  an  example,  a  formidable  landslip  occurred  on  the 
15th  November,  1879,  at  Vitznau,  on  Lake  Lucerne.  Here, 
at  the  foot  of  the  Eigi,  a  mass  of  earth  exceeding  35,000  cubic 
feet,  and  covered  with  trees,  fell  down  the  mountain  side  and 
tilled  a  depression,  burying  a  chapel  under  mud  to  a  depth  of 
twenty  feet. 

Landslips  occur  frequently  hi  all  mountain  chains,  and  in 
the  Himalayas  attain  vast  proportions ;  the  Gohna  landslip, 
in  1893,  for  instance,  brought  down  enormous  quantities  of 
rock  across  a  valley,  damming  up  a  tributary  of  the  Kiver 
Ganges.  This  led  to  the  formation  of  a  lake  10  miles  long 
and  500  feet  deep,  which  eventually  burst  the  dam  in  August, 
1894,  causing  a  flood  30  feet  deep  to  rush  down  the  Ganges 
valley  and  flood  the  town  of  Hardwar.  Owing  to  the  establish- 
ment of  telegraphic  communication,  and  to  careful  watching 
at  the  dam,  all  the  inhabitants  of  the  valley  received  timely 
warning  of  the  probable  bursting  of  the  dam,  and  no  lives 
were  lost. 

2.  Damage  dune. 
Soil-denudation  reduces  the  forest  area,  buries  plantations 
and  young  growth  in  mud,  injures  and  destroys  forest  roads 
and  other  works,  and  tills  up  ditches.  Ravines  that  become 
constantly  enlarged  by  surface  drainage  are  formed  on  hill- 
sides, whilst  the  beds  of  watercourses  are  raised,  interrupted 
and  altered,  by  the  material  brought  down  by  the  water; 
inundations  are  thus  caused.  The  amount  of  damage  done 
increases,  the  steeper  the  slope  and  the  more  broken  its 
contour,  and  the  looser  the  soil  and  the  greater  the  weight 
of  the  woody  growth.  Localities  where  landslips  are  likely 
to  occur  may  be  recognised  beforehand  in  wet  years  by  cracks 
forming  in  the  soil. 

3.  Protective  liulH. 
The  best  protective  rules  to  adopt  against  these  dangers  are: — 
(rt)  Careful  maintenance  of  a  continuous  woody  growth  on 
mountain-peaks,  ridges  and  all  dangerous  slopes.     Forests  in 


58+     PROTECTION  A0AIN8T  XOX-ATMOSPHKRIC  HHKNOMEXA. 

such  places  Q.ve  protection  forests,  and  should  be  managed  either 
b}'  selection  or  as  coppice.  For  mountain-tops  and  plateaux, 
the  selection  system  is  best,  when  accompanied  by  the  timely 
planting  uj)  of  all  gaps  that  may  occur  in  the  wood ;  but  on 


Fiff.  201. 


steep  slopes,  high  forest  presses  too  heavily  on  the  soil  and 
should  make  way  for  coppice  with  short  rotations. 

(b)  Wherever  a  landslip  is  to  be  feared,  the  bank  should 
be  kept  up  by  wattle-fences,  by  protection  of  the  soil-covering, 
and  by  not  extracting  the  stumps  of  felled  trees.  The  various 
protective  measures  which  may  be  adopted,  depend  on  the 
cause  of  the  danger  and   the  circumstances  of  the  locality. 


SOIL-DENUDATIOK.  5S5 

Surface-water,  or  subsoil-water,  for  instance,  may  be  con- 
ducted away  from  above  the  endangered  place  by  ditches  or 
drains.  All  quarrying  below  the  threatened  hill-side  must 
be  stopped. 

(c)  The  following  measures  provide  against  damage  by  a 
mountain  torrent : — 

i.  Eeafforesting  the  collecting-area  of  the  stream ;  the 
methods  to  be  adopted  for  this  ol)ject  are  described 
further  on. 

ii.  Securing  the  sides  and  bed  of  the  torrent  by  revetments, 
from  its  collecting  area,  downwards. 

iii.  Reducing  the  force  of  the  stream  by  terracing  its  bed, 
and  constructing  across  the  stream  wattle-work  fences  or 
masonry  works  which  keep  stones  and  silt  from  accumulating 
in  the  lower  parts  of  the  stream. 

iv.  Terracing  the  slopes  of  the  valley  on  either  side  of  the 
stream,  and  fixing  them  by  means  of  sowings  or  plantations. 

4.  Remedial  Measures. 

When,  in  spite  of  ev^ery  care,  landslips  or  ravines  have  been 
caused  by  abnormally  heavy  rain,  or  by  melting  snow,  pro- 
tective works  should  at  once  be  constructed.  A  revetment 
made  of  wattle-work,  or  of  logs  fixed  in  position  by  piles 
driven  into  the  ground  (Fig.  261,  A),  may  prevent  the 
occurrence  of  further  damage.  If,  however,  the  landslip  is 
extensive,  several  such  constructions,  one  above  the  other, 
must  be  made,  and  the  earth  between  them  be  brought  to  a 
uniform  slope  and  planted  up.  In  certain  cases,  complicated 
masonry  revetments  are  required. 

In  order  to  make  natural  revetments  (Fig.  261,  B  and  C) 
woody  growth  must  be  on  the  spot.  The  bush  is  partly  cut 
through,  S2)lashed,  and  pegged  down,  with  its  crown  uphill. 
"Where  there  is  no  woody  growth,  trellis- work  with  living 
branches  of  willows  or  dead  branches  (Fig.  261,  D  and  E) 
should  be  employed.  Fig.  261,  F,  shows  how  these  willow 
trellises  may  be  planted  along  a  slope.  Wherever  a  landslip  is 
feared,  adjoining  trees  should  be  felled,  as  they  would  otherwise 
fall  in  and  add  to  the  damage. 


5S6  PR0TE(."TI0X  AGAINST   INUNI>A'l'IONS. 

Section  IL — Inundations. 
1.  Causes  of  Iitinuhiti(»is. 

Inundations  originate  in  valleys  and  plains  owing  to  the 
sudden  thaw  of  masses  of  snow  in  the  mountains  or  plateaux 
ahove  them,  or  to  prolonged  or  heavy  rainfall,  or  to  the 
interruption  of  watercourses  hy  landslips. 

The  last  of  these  causes  is  frequently  due  to  clearing  forests 
from  mountain  sides,  and  to  l)ad  management  of  protection 
forests.  When,  on  hill-sides,  the  effects  of  rain  and  surface- 
drainage  are  not  reduced  hy  a  full  leaf-canopy  and  hy  the 
hinding  effects  of  the  roots  of  the  tree^  on  the  soil,  as  well 
as  the  sponge-like  action  of  the  natural  soil-covering  of  dead 
leaves  and  moss  on  the  surface-water,  the  latter  runs  down 
unimpeded  into  the  valleys,  hringing  with  it  quantities  of 
houlders,  gravel,  silt  and  mud ;  this  raises  the  beds  of  the 
watercourses,  and  causes  them  to  overflow  and  spread 
destruction  far  and  wide  into  the  lower  country,  especially 
by  leaving  cultivated  lands  covered  with  gravel  and  silt  after 
the  floods  have  subsided. 

Most  inundations  in  Central  Europe  occur  in  April,  when 
they  are  due  to  the  general  melting  of  the  mountain  snow,  or 
in  August  or  November,  owing  to  heavy  rainfall. 

2.  Damage  done. 

Inundations  carry  away  the  soil-covering  and  humus  from 
forests,  causing  sw'amps  and  cold  soil ;  they  destroy  young 
plants,  hinder  the  formation  of  coppice-shoots,  interrupt 
fellings  and  the  export  of  forest  produce,  and  often  carry 
away  timber  to  great  distances.'  The  floating  wood  endangers 
bridges,  river-bank  protection  works,  and  works  constructed  to 
facilitate  the  floating  of  timber.  In  spring-floods,  trees 
growing  along  the  banks  of  streams  may  suffer  from  the 
friction  of  the  ice  which  is  carried  down,  ^[an}'  game-animals, 
especially  roe-deer,  are  drowned. 

The  mud  brought  down  by  the  flood,  however,  richly  com- 
pensates for  the  loss  of  soil-covering  and  humus.  River  mud 
contains  not  only  nutritive  mineral  salts,  but  yields  lime  in 
a  ffne  state  of  division,  which  is  therefore  readily  absorbed  by 


INUNDATIONS.  587 

plants,  and  is  an  excellent  manure  for  lands  that  are  poor  in 
lime.  The  higher  the  floods,  the  greater  is  the  deposit  of 
mud. 

Dr.  Schulze  of  Darmstadt  gives  the  following  percentages 
for  the  constituents  of  Ehine  mud  : — 


1871. 

1872. 

Potash      . 

0-43 

0-19 

Lime 

.       14-06 

15-65 

Phosphoric  acid 

0-13 

0-11 

Humus     . 

2-86 

2-12 

Per  cent. 

Ter  cent. 

13-3 

17-5 

0-08 

0-14 

1-1 

4-4 

Professor  Nessler  of  Carlsruhe  found  the  following  con- 
stituents in  mud  from  the  Upper  Pihine. 

CaO  ... 

P.2O5  .         .         . 

Huunis     . 

The  average  amount  of  calcium  carbonate  was  27'5  per 
cent.  The  percentages  of  potash  and  phosphoric  acid  are 
small,  but  always  greater  than  in  ordinary  agricultural  soil. 

Besides  the  supply  of  large  quantities  of  soil,  the  utility 
of  floods  also  consists  in  the  increase  in  subsoil-w'ater, 
specially  useful  for  forests  in  dry  years,  and  the  destruction 
of  rabbits,  mice,  cockchafer-grubs,  etc.,  that  burrow  in  the 
ground. 

The  greatest  recent  floods  in  Central  Europe  in  1856,  1868, 
1879,  1882,  1885,  1888,  1889,  1890,  1892,  1896,  1897,  and 
1899,  chiefly  aftected  the  Alpine  districts  of  France  and 
Switzerland,  Hungary  and  Austria. 

In  1856  the  Rhone  caused  fearful  floods,  which  drowned 
numbers  of  people  and  damaged  property  to  the  extent  of 
A'S, 000,000.  One  of  the  results  of  these  floods  was  the  enact- 
ment by  the  French  Legislature  of  the  laws  for  the  rehoisement 
of  the  denuded  mountain-sides,  of  the  28th  July,  1860,  and 
of  the  8th  June,  1864,  for  regazonnemcnt,  or  restocking  them 
with  grass.* 

*  "Forest  Law,"  Baden- Powell,  lSii3,  p.  218.  Laws  for  the  protection  of 
inountaiii  forests  in  Gerniauv,  Switzerland,  and  Italy  are  also  referred  to. 


0  88  I'ROTECTION   AGAINST    INUNDATIONS. 

Terrible  floods  occurred  in  Switzerland  in  1868,  and  in 
Hungary  in  the  valley  of  the  Eiver  Theiss,  in  March,  1879. 
In  September,  1882,  damage  estimated  at  d£l,000,000  was 
caused  by  floods*  in  Carintliia  and  the  Tyrol,  and  there 
were  serious  floods  in  the  Rhine  valley  in  1882,  and  in  the 
regions  of  the  Elbe  and  Oder  in  1888.  The  great  floods  in 
Silesia  and  Brandenburg  in  the  suminier  of  1897,  caused  the 
promulgation  of  the  law  (1898 — 99)  for  protection  of  the 
tributaries  of  the  left  bank  of  the  Elbe,  in  Silesia.  Extensive 
floods  occurred  in  the  Thames  and  Severn  valleys,  and  other 
districts  in  the  South  of  England,  in  November,  1894. 

Serious  floods*  occur  in  Northern  India  nearly  every  year 
between  July  and  September,  after  the  commencement  of  the 
summer  monsoon,  and  owing  to  the  great  damage  thus  caused 
to  irrigation  canals  fed  by  the  Ganges  and  Jumna  rivers,  the 
forests  on  the  southern  slopes  of  the  Siwalik  Hills  are  now 
managed  as  protection  forests.  The  Indian  forest  oflicialst 
have  for  years  recommended  the  adoption  of  similar  measures 
to  the  lower  hills  between  the  Jumna  and  Sutlej  rivers,  as 
the  first  burst  of  the  monsoon  on  the  annually  grazed  and 
burned  sandy  hills  above  the  Hoshiarpur  district  causes  most 
disastrous  inundations  every  year,  besides  bringing  down 
quantities  of  sand,  gravel,  and  boulders  which  have  encroached 
considerably  on  the  agricultural  land  below  the  hills,  so  that 
by  1891,  lands  belonging  to  914  villages  were  affected,  and 
30,000  acres  of  richly  fertile  and  long  cultivated  land  laid 
waste,  besides  immense  damage  being  done  annually  to  rail- 
way and  road  embankments,  etc.  The  hills  were  formerly 
covered  with  forest  growth,  but  during  the  last  forty  years, 
flocks  of  goats  and  herds  of  buffaloes  belonging  to  about 
eighty  hamlets  of  squatters  have  been  allowed  to  browse 
down  and  destroy  the  forest  growth  which  formerly  fixed 
the  soil  on  the  hills,  and  would  spring  up  again  were  the 
annual  grazing  and  burning  of  the  undergrowth  restricted. 
A  law,  termed  the  Siicalik  Act,  was  passed  by  the  Punjab 
Legislative   Assembly    in    1900,    which    permits   the    Local 

*    vide  "  Indian  Forester,"  vol.  xii.,  p.  i\^. 

t  Ibid.,  vol.  v.,  p.  3.  Hadeu-Powell's  Ileport.  Moir's  Keport,  vol.  x.,  p.  271  ; 
\'o\.  xiii.,  p.  r)2.")  ;   vol.  xvii..  p.  21(! 


INUXDATION.S.  589 

Government  to  make  rules  regulating  the  cultivation  of 
land,  the  felling  or  firing  of  trees,  quarrying  and  pasture 
on  such  areas. 

3.  Protective  Rules. 

Private  agency  can  usually  do  little  or  nothing  to  prevent 
floods.  The  action  of  the  State  is  indispensahle,  as  the  cost 
of  the  erection  and  maintenance  of  the  works  necessary  to 
secure  this  ohject  is  quite  out  of  proportion  to  the  value  of 
the  property  on  which  they  must  be  erected,  and  the  work 
of  fixing  the  beds  of  mountain  torrents  and  reafiforesting 
hill-sides  in  process  of  denudation  must  be  carried  out  over 
a  large  area. 

The  most  effective  measures  depend  on  the  careful  manage- 
ment of  mountain  forests  in  the  catchment-areas  of  dangerous 
watercourses,  the  main  princi2)Ic  being  to  meet  the  danger  at 
its  sou7\-e. 

Although  observant*  people  discovered  these  facts  and  wrote 
about  them  a  century  ago,  a  long  time  elapsed  before  improved 
forest  management  and  the  erection  of  the  necessary  works 
were  undertaken  in  regions  that  were  threatened  in  this  way. 
Serious  and  successful  action,  however,  is  now  being  taken  in 
France,  in  Austria-Hungary,  and  in  Switzerland,  to  counteract 
the  causes  of  floods. 

The  chief  rules  to  be  followed  are : — 

i.  Regulation  of  Torrents  and  their  Feeders. — The  following 
account  of  torrents  is  taken  from  an  address  by  Fankhauser, 
to  the  Berne  Forestry  Association,  June  18th,  1897. 

In  every  torrent  there  are  three  distinctly  marked 
divisions : — 

1.  The  catchment  area. 

2.  The  channel  course. 

3.  Tlie  cone  of  debris. 

The  principal  mass  of  water  forming  a  torrent  comes  from 
the  catchment  area.  Single  drops  of  rain  falling  on  the 
topmost  ridges  flow  down  their  bare  sides  in  fine,  thread- 
like streams,  and  unite  into  larger  and  larger  brooks.     Mere 

»  VoM  Aueif^ljerg,  Fiinsinuck,  1779. 


590  PROTECTION    A(;AlXSr    IXLTXDATIOXS. 

drops  wash  away  only  earth  and  sand,  and  loosen  the  larger 
rocky  masses,  hut  the  hrooks  carry  down  stones  and  gravel. 
The  masses  descending  on  all  sides  are  received  hy  the 
channel  course.  After  heavy  rain,  the  raging  torrent  rushes 
down  its  narrow  hed,  weighted  with  earth,  sand  and  stones. 
It  tears  away  and  undermines  fresh  material  from  the  hed 
and  sides  of  the  stream,  and  the  projecting  banks  give  way 
and  add  to  the  moving  debris. 

When  the  torrent  emerges  from  its  narrow  hed  into  the 
level  plain,  its  force  diminishes.  The  rubbish  is  heaped  up 
into  a  cone  of  debris,  or  may  be  washed  away  by  a  larger 
stream  or  river. 

The  most  striking  phenomenon  in  each  torrent  is  the 
varying  amount  of  water.  Tiie  Ehine  at  Basel  varies 
between  its  highest  and  lowest  level,  as  1  :  20.  The  torrent 
of  Faucon,  in  the  Lower  Alps,  once  carried  oflf  70  per  cent, 
of  the  rainfall,  or  60,000  cub.  m.  of  water,  in  twenty  minutes, 
and  at  the  same  time,  180,000  cub.  m.  of  rub])ish. 

By  regulating  torrents  and  their  feeders  the  formation  of 
the  products  of  denudation  is  reduced,  the  velocity  of  the 
water  is  slackened,  earth,  gravel  and  boulders  are  retained 
in  the  mountains,  while,  if  possible,  a  steady  and  continuous 
flow  of  water  is  maintained. 

Works  of  the  following  nature  should  l)e  designed  in 
accordance  with  the  nature  of  the  locality,  the  characters 
of  torrents,  the  area  of  the  collecting  ground,  and  the  funds 
available : — 

(a)  Barricades  of  trees  with  their  entire  crowns  thrown  across 
torrents,  or  stones  strongly  joined  together,  with  a  tree  in 
front  of  them.  These  protect  the  base  of  the  torrent  from 
deepening.  Large  masonry  barricades  are  best  made  bow- 
shaped,  with  the  bend  up-stream.  The  nearer  they  are  to 
one  another,  the  better  protection  they  afford. 

{b)  Pavinfi  in  masonry  the  hed  of  the  torrent.  This  not  only 
prevents  deepening,  but  also  obstructs  the  carrying  down  of 
silt,  etc.  These  linings  are  made  as  in  Fig.  262,  A  and  B.  The 
bow-shaped  form  A  is  preferable,  but  the  polygonal  form  is 
easier  and  cheaper  to  construct,  and  suffices  when  the  debris 
is  not  composed  of  very  large  pieces. 


INUNDATIONS. 


501 


(c)  Valley-revetments .  (German,  Thahperrcn  ;  French, 
Bnrraries.)  These  are  constructions  that  reduce  the  gradient 
of  the  torrent  bed  and  the  destructive  power  of  the  water. 


Fig.  262. 

They  protect  not  only  the  bed  of  the  torrent  below  them,  but 
raise  its  level  l)ehiud  them. 

These  revetments  may  be  made  of  wood  or  of  masonry, 
the  latter  owing  to  its  superior  durability  is   far  preferable. 


I'ig.  263. 

Their  mode  of  construction  varies,  according  to  circumstances  ; 
they  are  erected  at  regular  intervals  and  collect  silt  and 
stones  behind  them.  For  small  torrents  and  where  rapid 
cheap   work    is    required,    mere    wattle-fences    may    suffice. 


592  PROTECTION    AOAINSr    INUNDATIONS. 

Fig.  263  shows  how  a  valley  is  protected  by  a  series  of 
barrages. 

(f/)  Wattle-fences.  These  consist  in  simple  wattle-fences 
made  in  curves  and  almost  horizontal,  the  central  point  being 
somewhat  lower  than  the  sides ;  they  are  afterwards  raised 
as  the  l)ed  of  the  torrent  rises  (Fig.  264,  A  and  B).  When 
further  denudation  is  no  longer  feared,  the  middle  of  the 
ravine  is  paved  with  stones  as  shown  in  Fig.  264,  C.  The  first 
fences  are  erected  at  distances  apart  of  three  meters  ;  they 
are  commenced  from  below  and  continued  up-stream.  Their 
erection  is  continued  until  the  bed  of  the  ravine  is  raised  high 
enough  for  no  more  denudation  to  be  feared. 

This  simple  plan,  devised  in  1838  by  Jenny,  is  advisable 


A  EC 

Fig.  264.— Jenny's  Wattle-Fences. 

where  only  mud  free  from  large  stones  comes  down,  and  for 
lateral  ravines  leading  into  the  main  torrent. 

(e)  Addenda.  All  the  above-mentioned  works  serve  to 
secure  the  bed  of  the  torrent.  The  question  of  maintaining 
its  sides  will  be  discussed  further  on. 

Such  works  are  useful  in  districts  with  granite  or  other 
rocks,  other  than  limestone.  Torrents  coming  from  limestone 
districts  or  from  glaciers  cannot  be  properly  regulated. 

In  connection  with  the  above  works,  the  slopes  leading 
down  to  the  torrent  must  be  properly  graded,  and  a  system 
of  horizontal  protective  trenches  laid  out,  so  as  to  cut  ofif  the 
soil-water  and  distribute  it  over  a  larger  area.  These  trenches 
have  proved  extremely  useful  in  preventing  floods.  They 
are  beneficial  to  forest-vegetation,  facilitate  plantations,  and 
also  revi  e  the  original  springs  of  water. 

The  local  forest-staff  should  carrv  out  the  above  works  and 


INUNDATIONS.  593 

should  possess  the  necessary  technical  and  local  knowledge 
to  do  so. 

In  France,  np  to  1898,  the  Government  had  acquired 
375,000  acres  in  mountain  districts  for  rehoisement,  and 
spent  £13,100  in  1905-6  on  the  necessary  works,  having  by 
1892  spent  altogether  £1,820,000  on  the  rehoisement  of 
156,197  acres. 

Extensive  works  have  also  been  carried  on  in  Austria 
since  1882,  £180,000  having  been  spent  up  to  1891.  In 
Switzerland,  in  the  four  years  1894-7,  about  £50,000  has 
been  spent  for  the  rectification  of  torrents,  in  engineering 
works  and  planting. 

ii.  Wasteland  in  Mountain  Regions,  especially  on  sloping 
ground,  should  be  planted  up,  and  the  forests  in  such  regions 
carefully  maintained. 

Surell,*  in  1811,  published  a  paper  on  the  subject,  making 
the  following  assertions  : — 

(a)  The  covering  of  mountain  soil  with  well-managed  woods 
prevents  the  formation  of  destructive  torrents,  whilst  the 
clearance  of  mountain  woodlands  favours  them. 

(h)  The  rehoisement  of  mountain  districts  will  rectify 
mountain  torrents,  while  the  clearance  of  forest  and  its 
soil-covering  doubles  the  strength  of  the  torrents,  and  causes 
new  ones. 

A  treatise  on  forest  protection  cannot  go  very  far  into  the 
subject  of  the  management  of  mountain  forests.  The  following 
remarks,  however,  are  useful : — 

The  forest  should  be  under  the  selection  system.  Planting 
is  better  than  sowing  for  wasteland  and  blank  spaces.  The 
species  to  be  cultivated  are  chiefly  Mountain  and  Cembran 
pines,  larch  and  spruce.  The  lines  of  plants  should  be  at  an 
angle  of  45^  to  the  course  of  the  torrent.  Grass  seed,  consist- 
ing of  a  mixture  of  Arena  elatior,  L.,  Bromus  erectus,  Huds., 
Holcus  lanatus,  L.,  should  also  be  sown.  Uprooting  of  trees 
and  stumps  in  fellings  must  be  abandoned.  Pasture,  usage 
of  litter  and  other  destructive  forest  usages  must  be  absolutely 
forbidden. 

*  "  Etude  sur  les  Torrents  des  Hautes  Alpes."     Paris,  1811. 
F.P.  Q   Q 


5^14. 


i>R(yn-:ci"iox  acjainst  inundations. 


iii.  Pu'iinUii'um  of  tli?  IjOucv  Course  of  the  Stream,  in  oider 
that  it  may,  as  far  as  possible,  l)e  able  to  carry  away  liisb 
floods  without  danger  to  the  surrounding  country.  A  river  is 
said  to  be  reguUted  when  the  water  is  in  the  middle  of  the 
bed  and  flows  away  evenly,  and  the  banks  are  firm. 

In  regulating  watercourses  the  following  points  must  he 
attended  to  : — 

a.  The  pro/ile  of  the  watercourse  must  he  normal.  It  must 
be  deep  enough  to  carry  down  small  dehris 
when  there  is  an  average  quantity  of  water, 
and  also  wide  enough  to  carry  off  floods 
without  acquiring  any  great  velocity.  Too 
narrow  beds  must  be  widened,  and  too 
broad  beds  reduced  in  width.  I   ; 

h.  The  (jrddient  of  the  bed  of  the  water-  "\    !    | 

course  must  he  so  modified  that  its  velocity  ;    )      ; 

will  rj3t  be  too  great  nor  too  slow.     The       ^^ ■■      \  \ 
former  is  effected  by  means  of  weirs,  and       (    .  \  \ 

the   latter   by    shortening    its   course,    as       ^     "^^~~-~~\V 
shown  in  Fig.  265.  "^ 

r.  Fixation    of    the    River -hank  a.     This  \^^ 

can  ho  done  by  plantations,  or  by  special  Fig.  2g.j. 

worlis. 

For  a  full  account  of  the  measures  to  be  taken  in  the  lower 
part  of  a  stream,  see  Vol.  Y.,  "  Forest  Utilization,"  p.  374. 


•J.  Maiiaficiiient  of  lu>rests  o)i  Land  Uolile  to  Iiniiiddtioiis.* 
The  management  of  forests  on  land  liable  to  be  flooded 
includes  much  that  is  special  to  the  circumstances  of  the  ease. 
S[)ecies  should  be  chosen  that  can  withstand  a  good  deal  of 
moisture  in  the  soil  and  occasional  submersion  ;  such  are  the 
pedunculate  oak,  elms,  black  alder,  willows,  black  and  white 
poplars,  and  the  ash.  In  the  wettest  places  the  common  alder 
and  willows  are  found  ;  ash  is  more  sensitive  to  soil-moisture 
than  poplars  and  the  peduncuhxte  oak. 

Among  exotics  are,  Juglaus  nigra,   L.,  Carya   alha,   Nutt., 
('.    amara,    >Hutt.,    Acer    californienm,    Ton'.,    and    Fra.rinns 

"-  Itebniann,  "Die  Rheitiwalduiigen  und   deren    Bevvirlhshaftung.''      Allgo- 
niiue  Kor.st.  u.  .Jagd.     Zcitiuig,  IS'.Ki,  pp.  :<t;u— 3sl. 


IXL'NDATIOXS. 


593 


americana,   L.  ;   the  latter  witlistands 'water  better  than  tlie 
common  ash. 

Pollardinf^.the  Selection  system,  and  Coppice-with-standards, 
rich  in  standards,  aresuital)le  systems  of  management.  Tree- 
willows  may  be  pollarded,  but  poplars  are  best  managed  by 
cutting  only  their  side  branches,  as  pollarded  poplars  soon 
decay.  Both  poplars  and  willows  speedily  reproduce  the  bark, 
which  has  been  rubbed  off  by  ice ;  they  are  generally  grown 
from  strong  cuttings.  Oak,  elm  and  ash  may  he  grown  in 
Higli  Forest. 

Ileproduction   is  effected    l)y  planting  saplings  and   slips, 
as  natural  regeneration  is  difficult  to 
A     obtain  on  areas  liable  to  floods. 

A  large  number  of  saplings  must  be 

planted,  to  replace  those  that  are  injured 

by  floods  and  to  kill  blackthorn  and 

y  ^/^        ^  other  noxious  weeds.  • 

T'ii     y^ ^  /^  In  the  case  of  Coppice-with-standards, 

'    ^  a  much    larger   ni>mber   of   tellers    is 


'vms\. 


Fis.  2(56. 


J    V    E    n    ju    m  Ji''    m 

Fi<^.  267.— Section  from  A  to  B,  showiti" 
comparative  heights  of  wood. 


reserved  at  each  felling  than  is  usually  the  case  under  this 
system,  in  order  to  keep  down  inferior  species  such  as  black- 
thorn. Osier  beds,  chiefly  of  HaUx  viviiiiaUs,  S.  jmrpurea,  etc., 
may  be  planted  by  means  of  cuttings,  and  cut  over  annually. 

In  the  case  of  High  Forest,  or  Coppice-with-standards,  the 
felling-areas  should  be  arranged  at  an  oblique  angle  with  tlie 
course  of  the  stream  as  shown  in  Figs.  2G6  and  2G7,  I.  being 
the  youngest  and  VIII.  the  oldest  wood,  and  alternate  compart- 
ments differing  in  age  by  half  the  rotation. 

Such  an  arrangement  affords  shelter  to  the  young  growth 
and  prevents  floods  from  carrying  away  beyond  the  next  strip 
of  wood  the  felled  timber  lying  on  any  area. 

Q  Q  2 


590  PHOTECTION    AfJAINST    SWAMPS. 

Fellings  should  take  place  when  the  water  is  lowest,  or 
when  it  is  frozen.  Timher  should  be  removed  up  to  the 
advent  of  spring,  and  the  conimeneement  of  the  floods. 
Grass-cutting  and  removal  of  litter  may  be  carried  on  freely 
in  such  forests,  without  danger  of  impoverishing  tlie  soil, 
which  is  enriched  by  the  annual  floods ;  pasture,  liowevei', 
should  not  be  allowed. 


Section  III. — Swamps. 
1.  Formation  of  Sicawj^s. 

The  soil  of  a  locality  becomes  wet  when  the  drainage-water 
has  not  a  sufficient  outlet.  If  there  be  no  outlet  for  the  water, 
swamps  or  peat-bogs  may  be  formed.  Either  swamps  or  bogs 
may  be  caused  by  rain,  snow-  or  spring-water,  or  water  from 
rivers^nd  ponds. 

Drainage  may  bo  prevented  either  ImrizoutaUii  or  vertically, 
the  former  if  the  water  cannot  escape  superficially  owing  to  an 
insufficient  fall  of  the  ground  ;  the  latter,  if  it  cannot  escape 
by  penetration  into  the  subsoil  owing  to  an  impermeable 
substratum  of  clay,  turf,  clayey  or  marly  loam,  soil  encrusted 
with  iron,  or  massive  rock,  especially  in  horizontal  layers. 
Sometimes  both  these  causes  are  at  work,  when  the  harm 
done  is  intensified.  The  local  causes  of  swampiness  may  vary 
considerably. 

{a)  In  loir-li/i}ifi  ])hiiiis,  swampiness  is  generally  caused  by 
flowing  water,  owing  to  a  slight  depression  in  the  ground  and  a 
stiff  soil. 

(h)  In  hasin-sliaped  valleys  along  watercourses  {Talaeg), 
swamps  may  be  caused  by  surface-water,  or  by  underground 
infiltration  from  the  stream  ;  the  former  happens  after  floods, 
when  the  overflow  cannot  find  its  way  back  into  the  stream, 
owing  to  the  presence  of  high  land  along  its  bank.  Part  of  the 
overflow  must  then  remain  on  the  low  land,  especially  when 
the  subsoil  prevents  the  descent  of  the  water.  Lagoons  along 
the  sea-coast  are  formed  in  this  way. 

Water  may  spring  through  permeal)le  soil  from  neighbouring 
watercourses,  and  when  it   thus  appears    in    depressions,   it 


FORMATION    OF    SWAMl'S. 


597 


denotes  a  high  level  of  water  in  the  stream  and  complete 
saturation  of  the  soil. 

(f)  In  hir/Ji  platcanx,  swampiness  is  due  to  heavy  rainfall,  or 
to  snowfall  with  subsequent  tliaw,  or  to  saturation  of  the  air 
combined  with  an  impermeable  subsoil  accompanied  by  the 
growth  of  swamp-forming  mosses  or  other  plants. 

{(l)  Swamps  on  a  hUlshle  are  generally  caused  by  springs,  the 
water  from  which  cannot  penetrate  into  the  ground  on  account 
of  a  subsoil  of  clay  or  of  horizontal  rocky  strata.     If  the  soil 


r-x 


i. 


\.      ,/^ 


Fig.  268. 
a.  Impermeable  stratum,     h.  Permeable  stratum,     r.  Water. 

on  a  hillside  should  be  permeable  above  and  impermeable 
below,  all  the  water  in  it  descends  to  the  base  of  the  hill, 
where  it  rises  above  the  ground-surface  and  forms  a  swamp 
(Fig.  268).  If,  however,  the  permeable  stratum  terminates  in 
the  slope,  drainage-water  will  spring  out  of  the  hillside,  along 
the  line  where  the  two  strata  coalesce. 


2.  JJaiiKtrje  done  hjj  Sn-anips. 

a.  General  Accon/il. 

The  damage  done  by  swampy  ground  is  as  follows  : — 
i.  Instability  of  the  trees,  which  favours  windfall,  especially 
of  the  spruce. 

ii.  Stunted  growth  and  liability  to  decay  in  the  roots  and 
stems  of  trees,  and  consequent.loss  of  increment  and  sometimes 
death  of  the  trees.  The  bad  growth  of  trees  on  wet  soil  is  due 
to  the  exclusion  of  oxygen  from  the  roots  and  to  the  low  tem- 
peratures of  the  soil  and  aii-,  as  wet  soil  may  reduce  air- tempera- 
ture by  9'  to  1-1   ¥.,  or  to  the  formation  of  humic  acid  and 


5"J8  I'RUTKCTION    AdAlX.vr    SWAMI'S. 

carbohydrates  instead  of  carbon-dioxide  in  the  soil.  Healthy 
growth  and  activity  of  roots  is  consequently  much  impaired. 

iii.  Increased  damage  by  frost,  sometimes  killing  off  young 
plants  (p.  499). 

iv.  Difficulties  in  forest  management  in  regeneration  and 
harvesting,  also  in  transport.  The  wetness  of  the  soil  increases 
the  difficulty  of  cultivating  it,  and  often  renders  spring-planting 
quite  impossible  ;  seeds  do  not  germinate  in  too  wet  a  soil,  and 
young  plants  often  perish. 

V.  The  tendency  of  a  swamp  to  increase  in  area  is  anotlier 
cause  of  danger  to  the  forest. 

b.  AcconliiKj  io  Species. 

Hardly  any  forest  species  can  withstand  continuous  stagnant 
wetness  of  the  soil,  but  the  degree  of  resistance  to  it  shown  by 
different  sjjecies  dift'ers  considerably.  Experiments  nuide  in 
the  Palatinate,  where  there  is  an  impermeable  subsoil,  show 
that  trees  resisted  a  very  wet  soil  in  the  following  order : — 
•  Pedunculate  oak,  elm,  poplars,  willows,  hornbeam,  common 
alder ;  ash,  sessile  oak  ;  Scots  pine,  spruce ;  beech,  silver-fir. 

It  is  strange  to  find  the  alder  so  low  in  this  scale,  as  other 
observations  tend  to  prove  that  this  species  can  withstand 
more  moisture  than  the  elm.  The  birch,  and  especially  Bctula 
jmhcsccns,  Ehr.,  will  withstand  much  moisture  in  the  soil,  and 
so  will  the  rowan  {I'ljrus  Aacuparia,  Gaertn.) 

r.  Age  of  Wood. 

Young  plants  are  frequently  killed  by  inundations.  Poles 
and  trees  on  swampy  ground  suffer  generally  from  root-decay, 
especially  the  spruce,  larch,  and  Scots  [)ine. 

d.  Loralihj  and  Nature  of  Soil-Cover'uui. 

Swamps  are  more  frequent  in  lowlands  than  on  hills  and  in 
mountain  districts,  on  massive  than  on  stratified  rocks,  and  on 
heavy  stiff'  soil  than  on  loose  soil.  Local  swamps  may  occur 
where  the  substrata  are  horizontal,  as  on  the  Jiuntersandstein 
in  the  Black  Forest. 

Certain  forest  weeds,  such  as  sedges,  reeds,  peat-planls,  and 


DAMACK    DONE.  59') 

especially  peat-moss,  predispose  to  swampiness,  wliilst  per- 
manent pasture  dries  up  the  surface-soil,  but  will  not  thrive 
on  very  wet  land. 

e.  Dcn^ihj  of  Ski luUiuj- Crop. 

Clearance  of  forests,  especially  in  mountainous  regions, 
favours  the  formation  of  swamps  ;  it  may  be  observed  as  a 
general  rule,  that  swampy  ground,  when  once  stocked  with 
young  wood,  becomes  gradually  drier  as  the  wood  grows  older 
and  covers  the  ground.  This  is  especially  true  for  coniferous 
forest,  and  the  efficacy  of  the  Scots  pine  for  draining  swamps 
is  well  known  in  Ireland,  where  many  bogs  have  been  formed 
on  the  former  sites  of  forests,  as  is  proved  by  the  presence  in 
them  of  bog-oak  and  other  woods.  The  damp,  cold  London, 
clay  at  Prince's  Coverts  near  Esher,  hardly  ever  dries  up  on 
the  roads  through  the  forest,  but  the  ash,  hazel,  and  alder- 
coppice  will  be  found  to  have  dried  uj)  the  soil  on  both  sides  of 
an  extremely  wet  road. 

In  the  forest  of  S.  Amand,  near  A'alenciennes,  in  1843,  about 
2,000  acres  was  v/et  heather  land,  the  soil  being  sand  with 
a  slight  mixture  of  clay.  This  was  gradually  planted  with 
Scots  pine,  and  these  trees  have  drained  the  soil  to  a  depth 
of  5  feet,  so  that  coppice  with  oak  standards  is  now  being 
introduced  in  place  of  the  pines.  Snipe  have  almost 
disappeared. 

The  valley  of  the  Upper  Khone  affords  a  warning  example 
of  the  effects  of  clearing  forests  on  the  formation  of  swamps  ; 
the  high  land  above  the  river  having  been  cleared  of  forest 
at  the  end  of  the  eighteenth  century,  in  order  to  afford  land 
for  agriculture.  Field-crops,  however,  have  made  way  for 
pasture,  and  the  quantity  of  hay  produced  annually  has 
decreased,  till  at  last  the  formerly  forest-clad  areas  have 
become  covered  with  moss  and  converted  into  swamps, 
lieafforesting  the  area,  as  in  the  Dammersfeld,  has  been 
attempted,  but  is  a  difficult  task. 

In  explanation  it  should  be  noted  that  in  mountain  regions 
with  a  cool,  humid  atmosphere,  which  is  unfavourable  to  evapo- 
ration, the  amount  of  water  taken  from  the  soil  is  proportional 
to  the  extent  of  leafy  hurfacj  exposeed   to  the  air,  and  to  the 


60U  PROTECTION    A(;ATNST    SWAMPS. 

surface  of  tlie  crowns  of  the  trees  standing  on  the  area.  The 
greater  the  amount  of  leaf-canopy,  the  more  atmospheric  pre- 
cipitation falHng  on  it  is  evaporated,  and  so  much  the  less 
reaches  the  ground.  Broadleaved  trees  act  in  this  manner 
during  the  season  of  growth,  hut  evergreen  conifers  throughout 
the  3'ear.  In  addition  to  this,  the  ahsorptive  action  of  the 
roots,  and  the  power  of  transpiration  possessed  by  the  foliage 
of  trees  must  be  reckoned,  as  Avell  as  the  suppression  of  swamp 
moss  by  the  cover  of  the  trees. 

Observations  made  between  1868  and  1871  at  the  double 
Bavarian  meteorological  stations,  -which  are  in  pairs — in  the 
forest  and  in  the  open — show  that  according  to  the  season  from 
25  per  cent,  to  32  per  cent,  of  atmospheric  precipitation  (rain, 
snow,  &c.),  and  averaging  26  per  cent,  for  the  whole  year,  did 
not  reach  the  ground  directly,  but  remained  on  the  crowns  of 
the  trees.  In  1882,  Fautrat  found  that  20  to  27  per  cent,  of 
rainwater  remained  on  the  trees  in  Alsace-Lothringen.  Much 
of  this  water,  however,  drops  from  the  foliage  or  trickles  down 
the  stems  of  the  trees  to  the  ground. 

There  are  certain  localities — for  instance,  level  land  with  an 
impermeable  substratum  and  high  atmospheric  temperature — 
where  swampiness  of  the  soil  is,  on  the  contrary,  increased  by 
forests.  In  such  cases,  the  rapidity  of  evaporation  depends  on 
the  unimpeded  action  of  the  sun's  rays  and  of  dry  winds,  and 
clearing  the  ground  of  forests  will  increase  the  effects  of  these 
forces. 

The  action  of  forests,  where  the  soil-covering  of  dead  leaves, 
moss,  and  humus  is  carefully  preserved,  in  maintaining  moisture 
near  the  surface  of  the  ground  and  protecting  the  soil  from  the 
effects  of  insolation  and  drying  wind,  is  very  valuable  on  hot 
aspects  and  steep  slopes,  especially  in  hot  countries,  where 
water  may  be  thus  stored  in  the  spongy  soil-covering.  A 
steady  supply  of  water  is  thus  maintained  in  springs  on  the 
hillside,  while  the  absence  of  tree  growth,  on  the  other  hand, 
allows  rainwater  to  drain  rapidly  down  and  causes  floods 
after  heavy  rainfall,  and  the  watercourses  may  run  nearly 
dry  during  the  hotter  months  of  the  year. 

Ebermeyer  has  proved  by  numerous  observations  that  on  a 
heavy  clay  soil,  the  root-zone  of  a  spruce  forest,  from  16  to  32 


DRAINAOK.  601 

inches  below  the  surface,  is  much  drier  than  the  correspondinfT 
zone  on  bare  fallow  land,  the  opposite  being  the  case  as  regards 
the  uppermost  layers  of  soil,  which  are  protected  by  the  leaf- 
canop3'  of  the  trees  from  insolation  and  the  drjdng  action  of 
winds,  while  the  moss  and  dead  needles  retain  much  moisture 
near  the  surface  of  the  ground.  Investigations  in  Eussia  by 
Ototzky,  and  in  France  by  Henry,  have  confirmed  this  in  the 
strongest  possible  manner,  and  for  other  trees  besides  spruce. 

/.  Season. 

In  countries  with  heavy  snowfall,  where  the  snow  remains 
lying  on  the  ground  throughout  the  winter,  the  soil  is  wettest 
in  the  spring,  after  the  snow  has  melted. 

In  the  south-east  of  England,  the  soil  is  probably  wettest 
from  November  till  iMarch,  but  dries  up  rapidly  after  the  1st  of 
March  till  July,  owing  to  the  scanty  rainfall  and  the  prevalence 
of  dry  east  winds. 

3.  Protective  Rules. 

(a)  In  mountain  regions,  and  in  very  rainy  districts,  such  as 
the  boggy  parts  of  Ireland,  where  the  formation  of  swamps  is 
to  be  feared,  forests  should  be  maintained  and  be  completely 
stocked,  and  shadebearing  conifers  are  best  for  the  purpose. 

The  spruce  probably  exercises  the  greatest  action  in  draining 
soil,  the  superficial  roots  of  this  species  acting  like  drain-pipes; 
the  Scots  and  Austrian  pines  are  also  very  useful  in  suitable 
localities,  and  retain  a  large  proportion  of  the  atmospheric 
precipitations  on  their  needles  and  branches. 

{}>)  Marshy  plants  should  be  removed  from  the  ground,  and 
in  damp,  low-lying  places  tlie  circulation  of  the  air  should  be 
increased  by  clearings,  thinnings,  pruning  and  removal  of 
undergrowth. 

(f)  All  ditches  and  watercourses  in  forests  should  be  kept 
open,  and  at  least  once  a  year  should  be  cleared  of  water- 
plants,  dead  leaves  and  mud. 

{(I)  Mountain  torrents  should  be  regulated. 

SkCTION    IV. UllAINAGE. 

A  superfluity  of  water  in  the  soil  can  be  thoroughly  rectified 
only  by  drainage.    Before,  however,  undertaking  such  a  work. 


(302  IMlolKCTIOX    A(;AINST    SWAMl'S. 

a  thorough  inquiry  should  be  made  into  all  the  bearings  of 
the  question,  as  extensive  drainage-works,  especially  in 
mountainous  districts,  may  damage  a  wide  tract  of  coun- 
try, and  thus  quite  outweigh  the  advantages  gained  by 
affording  a  larger  area  for  forest-growth  and  an  increased 
yield  of  wood.  Experience  shows  that  by  draining  swamps 
and  moorland  al  high  altitudes,  the  supply  of  moisture  to 
tlie  soil  and  atmo.sphere  may  become  so  reduced  that  forest- 
growth  and  agriculture  suffer  in  districts  lower  down.  This 
calamity  is  especially  liable  to  affect  older  deep-rooted  woody 
species,  and  woods  accustomed  to  plenty  of  moisture  in  the 
soil.  Drainage  causes  subsidence  of  the  soil,  and  thus  the 
roots  of  shallow-rooted  trees  such  as  spruce  may  become 
exposed,  while  pedunculate  oak  and  ash  may  become  stag- 
headed,  owing  to  their  roots  being  less  supplied  with  moisture 
than  was  formerly  the  case.  Before,  therefore,  drainage  is 
attempted,  the  demands  on  moisture  of  the  species  growing  or 
to  be  grown  on  the  drained  area  should  be  considered. 

Neighbouring  lands  may  also  be  affected  by  the  lowering  of 
the  level  of  the  underground  water  and  drying  up  of  the 
surface-soil,  which  may  have  bad  effects  on  ffeld-crops. 

If  the  drainage  of  mountain  forests  be  effected  on  a  large 
scale,  the  distribution  of  atmospheric  precipitation  may  be 
altered ;  the  drier  air  may  hinder  the  condensation  of  watery 
vapour,  and  the  formation  of  dew  and  clouds  may  be  lessened. 
Instead  of  frequent  gentle  showers,  irregular  storms  of  rain 
may  come  with  disastrous  results. 

A  further  disadvantage  is  the  reduction  of  the  quantity  of 
water  in  brooks  and  rivers,  by  which  timber-floating,  water- 
carriage  and  works  for  utilising  water-power  may  suffer 
seriously. 

Reuss  states  that  the  harm  done  by  ill-advised  drainage  is 
most  apparent  in  the  Dobris  mountain  forests  of  the  CoUoredo- 
Mansfeld  family;  through  the  extensive  drainage  system,  over 
50  miles  in  length,  effected  there  between  1858  and  1807,  the 
growth  in  forest  and  field  fell  oft"  to  such  an  extent  that  it 
became  necessary  to  fill  up  most  of  the  drains.  In  the  Ilarz 
mountains  also,  in  1810,  much  harm  was  done  by  too  exten- 
sive drainage,  whilst  the  atleiiii»ts  made  since  tlio  middle  of 


DRAINACK.  (iO'i 

the  present  century  to  drain  the  peat-hogs  in  the  Hannoverian 
Harz  districts  and  to  phmt  them  \vith  spruce  have  proved 
extremely  costly,  and  given  such  i)Oor  results  that  they  have 
now  heen  abandoned. 

On  the  above  grounds — the  danger  of  drying  up  sources  of 
useful  water-supply,  and  the  fear  that  benefits  resulting  from 
forest  drainage  works  may  not  repay  the  outlay  involved — the 
construction  of  such  works  on  a  large  scale  is  to  be  depre- 
cated, and  the  forester  should  not  as  a  rule  venture  beyond 
draining  small  local  swamps,  which  may  sometimes  be  ren- 
dered innocuous  or  even  useful  when  converted  into  fish  ponds, 
by  excavating  them  or  constructing  a  dam. 

From  a  general  view,  therefore,  of  the  matter,  it  follows 


a.  Vertical  drain.     I/.   Impermeable  stratum,     c.  Temieable  stratum. 

that  the  advantages  of  drainage  are  greatest  and  the  dis- 
advantages least  for  forests  on  fairly  level  ground,  whilst  the 
reverse  is  true  for  mountain  forests.  The  advantage  of 
draining  swamps  as  regards  sanitation,  circulation  of  the 
air  and  avoidance  of  malarial  fever,  need  only  be  referred 
to  here. 

The  following  methods  are  employed  in  drainage : — 

1.  Vertical  drainage. 

2.  Surface-drainage : — 

(a)  By  open  ditches. 

(/>)  Kaiser's  method  of  drainage. 

3.  Underground  drainage  by  covered  drains  : — 

(a)  liy  trenches. 

{b)  liy  glazed  pipes. 

(c)  By  ordinary  draining  tiles. 


601-  I'liOIKCTIOX    AdAINST    SWAMI'S. 

1.  Vcytital  I >rai)iafie. 

Vertical  drainage  is  carried  out  by  piercing  an  impermeable 
stratum  and  tbus  allowing  the  water  to  descend  into  a  lower 
permeable  stratum  and  be  thus  drained  off.  One  or  more 
borings  of  sufUcient  breadth  should  be  made  through  the 
impermeable  stratum  at  its  lowest  point,  as  siiown  in  Fig.  269. 

As  an  instance  of  the  effects  of  vertical  drainage,  the 
planting  of  part  of  the  Bagshot  sand  district,  near  Bagshot, 
by  Schlich  (1890-1900),  may  be  cited.  Tlie  land  was  mostly 
flat,  with  a  pan  6  to  18  inches  below  the  surface.  It  formed 
a  swamp  during  winter,  and  was  often  very  dry  in  summer. 
The  pan  was  bored  through  at  the  planting  holes  with  a 
pickaxe,  and  Scots  and  Weymouth  pines  planted.  This 
communication  between  the  upper  and  lower  strata  of  the 
soil  led  to  a  complete  drainage  of  the  surface,  and  a  fine  crop 
of  pine  trees  is  now  growing  there. 

2,  Surface  Drainage. 
a.  By  Open  Ditches. 

i.  MoDK  OF  Laying  out  a  Systkm  ok  Duains. 

The  mode  of  laying  out  a  system  of  drains  depends  on  the 
nature  of  the  locality.  On  level  ground  and  in  valleys,  a 
complete  network  of  drains  is  laid  out  after  the  land  has  been 
carefully  levelled,  and  consists  of  main  drains,  leaders  and 
feeders. 

The  main  drain  should  run  along  the  lowest  part  of  the 
area  to  be  drained,  necessary  excavations  being  made  to  give 
it  a  uniform  gradient  between  0"5  and  1  per  cent.,  and  to 
conduct  it  into  the  nearest  watercourse. 

The  leaders  must  carry  off  the  water  in  the  shortest  direction 
from  the  feeders  to  the  main  drain,  while  the  feeders  have  to 
collect  water  from  the  soil  and  conduct  it  to  the  leaders,  the 
direction  of  which  depends  on  the  gradient  of  the  ground. 
When  the  gradient  is  moderate,  the  main  drains  and  leaders 
should  run  along  lines  of  greatest  fall ;  if  it  is  too  steep,  their 
length  must  be  increased  by  causing  them  to  wind  or  bend  so 
that  the  drainage  water  may  not  wash  away  the  bed  or  sides 
of  the  drains,  and  cause  the  furniaiion  uf  ravines.     Tlie  best 


DRAINAOK. 


fi05 


fall  for  drains  is  from  0'5  to  1  per  cent.,  but  sometimes  the 
lie  of  the  ground  may  necessitate  a  certain  length  of  drain  of 
greater  gradient. 

Tiie  feeders  should  be  obliquely  inclined  to  the  line  of 
greatest  fall  in  order  to  collect  the  maximum  amount  of  water 
from  the  soil,  and  they  should  conduct  the  water  into  the 
leaders,  to  which  they  may  be  either  at  rif/ht  angles  or  oblique. 

The  former  system,  as  shown  in  Fig.  270,  has  the  advantage 
of  draining  the  largest  area  with  the  shortest  length  of  drain. 
Fig.  271  shows  ol)lique  drainage,  and  the  mor£  acute  the  angle 


Fig.  270.  Fig.  271. 

Plans  of  drainage,     h.   Main-drain.     ».  Feeders. 

between  tlie  feeder  and  leader,  the  less  will  be  the  area  drained 
by  a  given  length  of  ditches. 

Thus  a,  J),  c,  d  >    a,  h,  e,  f  >    a,  h,  g,  h. 

The  choice  of  the  angle  between  the  feeders  and  leaders 
depends  chiefly  on  the  gradient  of  the  ground,  the  less  the 
gradient  the  more  acute  the  angle ;  feeders  the  bed  of  which 
gradually  deepens  as  they  approach  the  leader  will  be  most 
effective. 

Feeders  can  be  laid  out  parallel  to  one  another  only  when 
the  gradients  are  uniform.  Figs.  272  to  274  show  some 
interesting  networks  of  drains  l)y  G.  Koch. 


fion 


PROTKCTION    ACAINS'I'    SWAMPS. 


The  proper  interval  between  the  feeders  depends  on  the 
quantity  of  water  to  he  drained  away,  the  configuration  of  the 
ground  and  the  nature  of  the  soil.  Tlie  interval  between 
any  two  feeders  will  be  inversely  as  the  quantity  of  water  in 
the  soil.  The  looser  the  soil,  the  more  easily  is  it  drained. 
On  the  average,  according  to  circumstances,  intervals  of  16  to 


Fi-r.  272. 


FiiT.  273. 


Fig.  274. 
Plans  of  drainage. 


22  yards  may  be  chosen.  In  very  wet  land,  the  interval 
between  the  feeders  may  be  reduced  to  10  yards,  whilst  on 
drier  land  it  may  be  extended  to  30  yards. 

A  practical  method  of  determining  this  interval  is  given  by 
Heyer,  as  shown  in  Fig.  275.  Cut  a  feeder  A,  and  another  B 
at  different  distances  from  A  till  the  water  in  the  soil  at  tlie 
middle  point  C  between  the  two  feeders  falls  to  the  depth  C  D, 
to  which  it  is  lequired  to  drain. 


DRAINAGE. 


007 


Water  percolating  from  a  river  should  l)e  collected  as  near 
it  as  possilile  by  dee^j  drains  running  along  the  river-side,  and 
leading  back  into  the  river  lower  down  stream.  Overflow 
from  a  stream  can  be  kept  back  only  by  the  construction  of 


embankments,  as  in  the  English  fen  districts,  or  along  the  river 
Severn. 

On  slopes,  water  should  be  collected  at  the  points  of  issue 
from  the  water-bearing  strata,  before  it  can  form  a  swamp. 
Thus  the  water  should  be  collected  in  a  drain  A-  A-  running 
along  a  contour-line  on  the  hill-side  (Fig.  276),  and  then 
conducted  down-hill  by  a  leader  A  along  the  line  of  greatest 


Fig.  276. 
/•.  Feeder,     a.  Main 
drain  at  the  base  of  ^ 
liill. 


^^       1 


Fig.  277. 
D.  Chief  feeder.     A.  Main  drain. 
B.  Leader  from   a  spring    q,   and  a 
small  swamp  /.     C.  Feeders. 

fall,  any  outlying  swampy  places  in  depressions  being  con- 
nected with  the  latter.  Wherever  the  fall  and  the  extent  of 
the  area  to  be  drained  are  considerable,  several  such  drains 
may  be  constructed,  one  above  the  other. 


008  PROTECTION    A(  JAIN  ST    SWAMPS. 

AVhen  the  gradient  is  slight  and  much  water  collects 
(Fig.  277)  in  a  swamp,  l)esides  the  main  drain  A,  a  few  con- 
fluent drains  should  be  cut,  that  lead  into  the  main  drain. 
They  should  join  the  main  drain  at  a  very  acute  angle,  so 
that  the  passage  of  the  water  in  it  may  not  be  interrupted, 
nor  its  walls  undermined  by  water  from  the  lateral  drains. 

ii.  Dimensions  of  thf.  Diiains. 

The  breadth  of  the  drains  depends  on  the  amount  of  water 
in  the  soil,  the  gradient  of  the  ground,  and  the  purpose  of  the 
drains.  The  wetter  the  soil  and  the  slighter  the  gradient, 
the  broader  must  be  the  ditches;  the  leaders  being  broader 
than  the  feeders,  and  the  main  drain  than  the  leaders.  From 
1  to  2^  feet  is  a  sufficient  width  for  the  feeders,  and  3  to 
5  feet  for  the  leaders  and  main  drain. 

The  depth  of  the  drains  depends  on  the  depth  to  which  the 
land  is  to  be  drained,  and  on  the  physical  nature  of  the  soil 


Fig.  278. 

and  subsoil.  Clay  requires  a  greater  depth  of  drainage  than 
loam,  and  this  again  than  sandy  loam.  In  peaty  soils,  the 
drains  should  go  down  to  the  mineral  subsoil.  In  practice, 
the  depth  of  drains  is  usually  half  their  width,  and  draining 
to  too  great  a  depth  is  prejudicial,  costing  in  excess  of  the 
requirements  of  the  case,  and  depriving  the  subsoil  of  reserve 
water  which  will  be  required  by  the  trees  during  dry  weather. 
The  amount  of  water  on  the  land  during  summer,  not  in  early 
spring,  should  be  considered  in  fixing  the  depth  of  drains. 

The  slope  of  the  sides  of  the  drains  depends  on  the  degree 
of  coherence  of  the  soil,  and  on  the  gradient  of  the  drain  ; 
the  looser  the  soil  and  the  steeper  the  gradient,  the  gentler 
must  this  slope  be.    In  Fig.  278,  a  is  one  meter,  and  the  slope 


DRAINAfJE.  609 

may  be  ^  on  peat,  1  on  clay  or  stiff  loam,  1^  on  sandy  loam, 
2 — 3  on  sand. 

The  main  drains  may  be  provided  with  sluices  at  suitable 
places,  so  that  they  can  be  closed  and  the  drainage  stopped 
during  dry  seasons. 

ill.  TiMK  FOR  Dkaining. 

Drainage  should  precede  planting  by  a  few  years,  so  that 
the  ground  may  become  sufficiently  dry  and  may  settle  down 
before  the  plants  are  put  in  ;  a  dry  period  of  the  year,  e.g.,  late 
summer  or  autumn,  should  be  chosen  for  the  execution  of  the 
work. 

iv.  Mkthod  of  Digging  the  Drains. 

Operations  should  be  commenced  with  the  main  drain  at 
the  lowest  part  of  the  land,  in  other  respects  the  system 
already  described  for  digging  boundary-trenches  should  be 
followed  (p.  18).  The  earth  removed  from  the  drains  should 
not  be  placed  too  close  to  them,  as  it  may  then  be  washed 
back  again  by  the  rain  ;  it  should  be  used  for  filling- up 
hollows  or  spread  evenly  over  the  surface  of  the  ground, 
which  is  beneficial  in  wet  places  by  raising  their  level.  After 
the  main  drain  has  been  dug  the  feeders  and  leaders  should 
follow.  It  is  most  economical  to  give  the  work  out  to  be  done 
on  contract. 

V.  Advantages  of  the  Method. 

The  advantages  of  the  method  of  draining  by  open  ditches 
when  compared  with  closed  drains  are : — 
Cheap  execution. 

Ready  discovery  of  places  requiring  repair,  and  cheapness 
of  repairs. 
Its  disadvantages  are : — 

Loss  to  the  forest  growth  of  area  occupied  by  the  ditches. 
Difficulties  in  transport  of  produce. 
Liability  of  the  ditches  to  damage  by  men,  cattle,  etc. 
Too   complete  and  rapid  removal  of  water.     This  may 
cause  temporary  injuries  for  want  of  moisture  in  the 
soil,  and  may  damage  lands  below  the  drained  area. 
F.P.  R    R 


610  I'UOTI-X'IION    AGAINST    SWAMPS. 

The  loss  of  area  taken  up  in  open  drains  is  not  of  any 
practical  importance  in  forestry,  and  provided  care  be  taken 
about  the  number  and  dimensions  of  the  ditches,  the  other 
disadvantages  of  the  method  may  to  some  extent  be  avoided. 
In  mountain  forests,  where  the  snow  is  long  in  melting,  and 
which  are  subject  to  unusually  heavy  rainfall,  a  system  of 
open  drains  along  the  line  of  steepest  gradient  removes  such 
a  large  volume  of  water  from  the  forest,  that  this  method, 
which  is  usually  employed,  especially  on  peaty  ground,  where 
the  flowing  water  in  the  drains  cuts  into  the  land  below,  is  of 
doubtful  expediency.  Under  such  circumstances  the  following 
method  is  preferable  : — 

I).  Kaiser''s  Metltod  of  Drainage. 

The  principle  of  Kaiser's*  method  of  drainage  consists  in 
avoidance  of  the  direct  removal  of  the  water  from  the  forest 
and  yet  in  a  complete  drainage  of  the  wet  land. 

This  is  effected  by  the  lowering  of  the  water-level  by  roeans 
of  a  number  of  interrupted  drains  {collecting  trenches)  dis- 
tributed uniformly  over  the  area  to  be  drained,  combined  with 
a  system  of  small  ditches  widening  out  laterally. 

The  collecting  trenches  are  1  to  2  meters  long,  about 
1  meter  deep,  and  1  meter  wide,  and  are  dug  horizontally 
along  contour  lines.  The  lateral  trenches,  that  unite  these 
collecting  trenches,  and  the  dimensions  of  which  correspond 
to  the  depth  to  which  the  water-level  is  to  be  reduced,  are  at 
right  angles  to  the  collecting  trenches. 

The  following  reasons  are  given  in  support  of  Kaiser's 
method  of  drainage  : — 

i.  In  every  case  too  rapid  and  complete  drainage,  with  its 
injurious  consequences,  is  prevented. 

ii.  The  degree  of  drainage  required  by  the  proposed  plan- 
tation is  completely  under  control,  as  the  lateral  drains  are 
dug  only  deep  enough  to  reduce  the  water-level  sufficiently. 
The  water  removed  from  the  soil  and  from  the  spoil-heaps 
that  remain  alongside  the  collecting  trenches  fills  the  latter 

*  Kaiser.  "  lieitrage  siii*  Pflege  der  Bodenwiithscliaft  niit  besondcre 
KUcksicht  auf  die  Wasserstandsfrage."     With  24  plates.     Berlin,  1S83. 


DRAINAGE. 


611 


and  the  lateral  drains  only  to  the  same  height  as  the  latter 
has  been  reduced  in  the  remainder  of  the  area. 

iii.  In  the  first  place,  evaporation  over  the  whole  area  is 
increased  by  the  action  of  the  sun  and  winds  on  the  exposed 
water  in  the  collecting  trenches.  In  the  second  place,  the 
surface  having  become  drier  and  warmer  by  the  drainage, 
increases  the  evaporation,  and  favours  the  capillary  ascent  of 
water  from  the  sub- 


soil ;  it  also  warms 
the  air  near  the  sur- 
face of  the  ground. 

The  results  of  this 
process  must  be 
favourable  to  the 
growth  of  plants. 
By  the  gradual  dry- 


Kaiser's  method  of  draina'je. 


ing  up  of  the  surface, 
peat-mosses  and  sour 
grasses  disappear 
and  the  chemical  and 
physical  condition  of 
the  soil  improve. 
The  formation  of 
peat  ceases  ;  the  de- 
composition of  the 
humus  becomes 

normal.  Lichens 
disappear  from  the  stems.  Danger  from  frost  is  diminished. 
Annual  shoots,  hitherto  short,  become  longer.  The  water  is 
thus  utilised  for  the  service  of  the  forest. 

The  above  method  was  tried  in  1888  and  subsequent  years 
in  the  Bavarian  Royal  forest  of  St.  Oswald  on  peaty  areas, 
it  is  represented  in  Fig.  279.  The  collecting  trenches  were 
dug  in  depressions  and  other  places  where  the  peat  was 
wettest.  The  lateral  feeders  were  30  to  45  centimeters  wide 
and  deep,  quite  deep  enough  for  young  spruce  to  become 
rooted  above  the  subsoil  water.  The  excess  water  was  con- 
ducted from  the  collecting  trenches  by  little  trenches  a  few 
centimeters  deep  into  a  small  watercourse  named  Seige,  which 

R  K  2 


612  PROTEC'l'ION    AGAINST    SWAMPS. 

conveyed  it  lower  down.  If  siicli  a  watercourse  does  not 
exist  a  drain  must  be  dug  to  receive  and  drain  away  the 
surplus  water.  The  system  of  drains  gave  admirable  results, 
and  the  cost  was  V2s.  per  acre,  that  of  the  upkeep  per  acre, 
2s.  anuuall}'. 

The  cost  of  open  drains  in  Germany,  in  1883,  was  about 
8s.  per  acre,  but  the  extra  cost  of  Kaiser's  drainage  is  incon- 
siderable when  compared  with  the  superior  benefits  obtained. 

The  only  objection  to  the  method  consists  in  the  fact  that 
the  collecting  trenches — at  least  in  depressions — form  so  many 
little  frost-holes,  that  increase  local  danger  from  frost. 

3.  Covered  Drains, 
a.   Tre?iches. 

i.    ilKTIlOI)    OF   CONSTllUCTIOX. 

Underground  drains  are  usually  made  as  in  Fig.  280. 
The  trenches  should  be  about  one  foot  broad  at  their  base, 
1^  to  2^  feet  deep,  and  with  a  slope  as  steep  as  the  nature  of 


Fig.  280  — Section  of  a  drain. 
(I.  Layer  of  stones,     b.  Layer  of  brandies,     c.  Layer  of  earth. 

the  soil  will  allow.  The  trench  is  then  half  filled  with  stones, 
which  are  covered  with  brushwood,  reeds  or  sods,  and  the  top 
is  filled  in  with  earth. 

Another  method  is  to  cover  the  base  of  the  trench  with 
fascines  or  tied  bundles  of  green  osiers,  branches  of  alder, 
poplar  or  shrubs,  which  are  used  immediately  after  they  have 
been  cut.  The  vacant  spaces  between  the  fascines  along  the 
sides  of  the  trenches  are  filled  up  with  moss,  and  the  whole 


DRAINAGE.  613 

covered  with  earth,  as  before.  This  mode  of  drainage,  known 
to  the  Romans,  was  introduced  into  England  by  P]lkiiigton, 
and  was  much  practised  until  1820.  It  has  the  advantage  of 
preventing  excessive  drainage,  and  may  serve  its  purpose  in 
places  to  be  planted  up,  until  the  roots  of  the  plants  can 
tliemselves  drain  the  soil. 

ii.   DritAiiir.iTY. 

Brushwood-drains  when  the  fascines  are  of  alder  brandies 
will  last  from  8  to  10  years  ;  they  rot  sooner  on  calcareous 
soil  and  last  longer  on  clay.  As,  however,  the  plants  once 
forming  a  thicket  themselves  drain  the  soil,  and  by  the  use  of 
fascines  too  much  water  is  not  removed,  this  method  is  highly 
advantageous. 

Drains  made  with  stones  may  last  for  50  years,  and  are 
therefore  preferable,  unless  temporary  drains  are  suilicienfc  for 
the  purpose. 

iii.   Vai.uI';  (jk  tmk  Miaiiou. 

Owing  to  the  high  cost  of  this  method  of  drainage,  it  is 
used  only  for  permanently  wet  ground.  It  is  also  largely 
employed  for  culverts  to  lead  water  across  roads. 

b.  Gl'tzci/  or  Came  at  J)rai»-pi/>e;'t. 

Drain-pipes  made  of  glazed  burned  clay  or  cement  and  of 
various  dimensions  are  now  generally  used  for  culverts ;  tiiey 
unite  the  advantages  of  rapid  drainage  and  facility  for  being 
cleaned,  with  that  of  great  durability. 

c.  /Jraini/it/   Tiles. 

i.    DKSUltll'TlON. 

Draining  tiles  are  cylindrical  tubes  of  burned  clay  with  a 
circular  section.  They  are  generally  1  to  1^  feet  long,  ^  to  | 
inch  thick,  and  their  apertures  1|-  to  Ah  inches  across.  A 
good  draining  tile  should  be  well-burned  and  smooth  within, 
it  should  ring  when  struck,  show  a  clean  uniform  fracture,  and 
stand  sudden  changes  of  temperature  without  cracking,  for 
which  it  may  be  tested  by  plunging  it  alternately  into  hot  and 


614  PROTKCTION    AOAINST    SWAMPS. 

cold  water.  The  clay  used  for  these  tiles  should  be  fairly 
pure,  and  contain  no  lime  nor  coarse  grains  of  sand.  The 
larger  tiles  are  used  for  main  drains  and  the  smaller  ones  for 
collecting  drains. 

ii.   Lay  INC  hie  Tilks. 

Trenches  for  the  tiles  are  similar  to  those  in  use  for  open 
drains,  their  dimensions  depending  on  the  nature  of  the  soil ; 
their  sides,  however,  should  be  vertical ;  the  main  drains  have 
a  fall  of  2  in  1,000,  and  the  collecting  drains  a  greater  fall, 
and  should  be  from  30  to  80  feet  apart  according  to  the  nature 
of  the  soil.  The  shortest  distance  for  collecting-drains  is 
chosen  when  there  is  much  subsoil-water  in  stift'  clay  or  in  very 
fine  grained  soil  with  great  capillarity  ;  in  fact,  the  looser  the 
soil,  the  further  apart  the  drains  should  be. 

The  depth  of  tlie  collecting-trenches  should  be  from  3  to  4| 
feet,  and  at  least  3^  feet  is  necessary  in  cold  climates,  to 
prevent  damage  to  the  tiles  by  frost;  the  main  drains  should 
be  somewhat  deeper. 

After  the  trenches  have  been  dug,  which  for  very  wet  soils 
should  be  in  fine  weather  and  with  as  little  delay  as  possible, 
the  tiles  should  be  laid  carefully,  beginning  at  the  upper  end 
of  the  drains,  and  placed  end  to  end  at  the  bottom  of  the 
trenches ;  or,  if  the  soil  be  loose,  on  a  layer  of  clay  or  on 
flat  roofing  tiles,  which  will  give  the  bed  of  the  drain  an  even 
gradient,  to  which  much  attention  should  be  paid.  Brown* 
recommends  placing  a  layer  of  stones  under  the  tiles,  in  which 
ordinary  drainage-water  may  run,  while  its  level  will  rise  to 
that  of  the  pipes  only  when  the  soil  happens  to  be  exceptionally 
wet.  This  is  because  the  rootlets  of  trees  are  attracted 
towards  wet  substances  in  the  soil,  and  will  therefore  branch 
freely  among  the  stones  and  yet  not  block  up  the  pipes,  which 
are  usually  dry.  Brown  also  advocates  placing  a  layer  of  clay 
over  the  pipes,  so  as  to  keep  the  upper  rootlets  from  getting 
into  them. 

The  size  of  the  aperture  of  the  tiles  depends  on  the  degree 
of  wetness  and  capacity  of  the  soil  ;  the  more  water  there  is 
to  be  removed  and  the  greater  the  danger  of  the  tiles  becoming 

•  •'  The  Forester."     I'.rown  and  Kisl)et.     Blackwood  &  Co..  18'.)t,  Vol.  I.,  .-..'■)]. 


DRAINAGE.  HI 5 

choked  with  soil,  the  larger  the  aperture  of  the  tiles,  and  in 
sandy  soil  it  should  be  at  least  two  inches. 

After  laying  the  tiles,  which  should  be  done  in  dry  weather, 
and  as  rapidly  as  possible,  the  trenches  are  filled  in  with 
earth,  and  the  greatest  care  should  be  taken,  especially  when 
the  soil  is  stony,  that  the  pipes  are  neither  broken  nor 
displaced. 

iii.    DUIIARFLITY. 

The  durability  of  the  drains  depends  on  the  nature  of  the 
soil,  the  quality  of  the  tiles  and  the  care  taken  in  executing 
the  work.  Well-burned  tiles  at  depths  of  3J  to  4^  feet  should 
last  for  25  years  and  more  ;  for  instance,  draining-tiles  laid  in 
1850,  in  the  Prussian  Crown  Estates,  were  in  good  orxler  in 
1880. 

The  cost  of  draining  with  tiles  is  about  M8  per  acre,  and 
this  is,  of  course,  prohibitive  for  purely  forest  w'ork. 

(/.  ('otii/inrifion  of  /))y'iin'7i//-7'i7fs  villi   Open  Drains. 

Drainage  improves  soils  by  lowering  the  level  of  subsoil 
w^ater,  and  exposing  a  larger  area  of  the  soil  to  the  influence 
of  atmospheric  air,  thus  rendering  it  warmer  and  accelerating 
the  decomposition  of  humus.  As  compared  with  open  drains, 
draining-tiles  waste  no  productive  area,  are  less  subject  to 
damage  and  drain  the  soil  better,  and  their  use  is  highly 
advisable  in  agricultural  lands,  but  in  forests  they  are  much 
more  costly  to  lay  out  than  open  drains,  and  they  easily 
become  choked  by  the  rootlets  of  trees  and  of  weeds  such  as 
Eqnisetum,  Arundo,  etc.,  and  also  by  frogs'  spawn.  Deposits  of 
iron-ochre  may  also  be  formed  in  the  pipes,  and  they  may 
become  filled  with  sand. 

Experience  has  shown  that  in  forests  all  the  disadvantages 
of  draining-tiles  occur  more  frequently  than  in  agricultural 
lands,  and  they  can  be  profital)ly  used  only  in  forest  nurseries, 
or  for  bad  forest  meadows.  The  production  of  hay  in  meadows 
may  be  increased  25  per  cent,  by  good  drainage,  and  the 
quality  of  the  hay  is  also  improved, 


616 


CHAPTEli   11. 

PROTECTION    AGAINST    AVALANCHES.* 

1.   Origin. 

Avalanches  are  caused  ])y  the  loosening  and  fall  of  masses 
of  snow  or  ice  on  steep  smooth  slopes  in  mountainous  regions; 
they  may  consist  of  loose  or  massive  snow,  or  both  combined, 
or  of  ice  from  broken  glaciers. 

n.  Avaldiiches  of  Loose  Snoiv. 

These  are  locally  termed  Stauhlaivincn,  and  occur  in 
November,  wlien  fine  dust-like  snow  is  falling ;  they  are  due 
to  great  steepness  of  the  mountain  sides,  or  to  overhanging 
masses  of  snow  falling  on  to  rocks,  the  snow  being  separated 
into  duh't  during  its  fall.  They  are  of  rarer  occurrence  than 
other  avalanches  and  seldom  cause  any  damage. 

b.  AvaJamlirs  of  Afassire  Snow. 

Movements  of  the  upper  layer  of  massive  snow,  termed 
Oherlawinen,  occur  chiefly  from  December  to  February,  when 
thick  layers  of  fresh  snow  have  fallen  on  to  old  frozen  snow, 
and  become  so  weighty  that  they  can  no  longer  rest  on  the 
smooth  base  beneath  them. 

r.   (tioinid  Ara/aiirhcs. 

AVhen  masses  of  snow  wliich  extend  down  to  the  surface  of 
the  ground,  roll  or  slide  down  a  mountain  side,  they  are 
termed  Grimdlawinen,  and  are  extremely  dangerous.  They 
generally  fall  towards  the  end  of  winter  at  midday,  during  the 
melting  of  the   snow,  and  when  a  7'V;////,  or  south  wind,  is 

•  Landolt,  El.,  "  Die  Bachc,  Sclmcelawinen  u.  Steiiischlage."  Zurich,  188(5. 
Pollack,  Vincenz,  "  Die  Lawinen  Oesterreichs  unci  dcr  Schweitz  und  deren 
Vcrbauunpeii."     Vicuna,  ISDl. 


PROTECTIVE    MEASURES.  617 

blowing,  and  frequently  during  a  storm.  These  are  the 
commonest  and  most  dangerous  avalanches,  and  leave  tracks 
which  can  be  readily  observed,  as  they  occur  over  and  over 
again  at  the  same  places. 

d.  Glacier- Avalanrhes 

Consist  of  broken  fragments  of  glaciers. 
The  following  remarks  apply  only  to  avalanches  of  massive 
snow  and  ground  avalanches. 

2.   Dtiiudtie  done. 

The  damage  done  to  foresfs  by  avalanches  consists  in  the 
breakage  of  all  woods  lying  in  their  way,  and  in  the  obstruc- 
tion of  streams  and  roads  which  they  cause.  The  rush  of  air 
that  accompanies  an  avalanche  is  so  great  that  it  breaks 
many  trees  up  to  a  distance  of  several  hundred  yards  from  the 
avalanche.  Many  ibex  are  also  killed  b}^  avalanches.  No 
forest  can  withstand  the  rush  of  a  large  mass  of  snow  down 
the  mountain  side,  and  the  higher,  smoother  and  steeper,  and 
freer  from  wood  a  mountain-side  is,  the  greater  the  danger 
of  avalanches,  and  the  greater  the  rapidity  with  which  they 
fall. 

A  high  soil-covering  of  hill  grass  affords  considerable 
protection. 

In  the  winter  of  1875-76,  in  the  district  of  liagaz,  of  the 
Swiss  canton  Graublinden,  500  avalanches  occurred,  and  in 
the  district  Schuls  of  the  same  canton,  881  avalanches.  The 
winter  of  1887-88  was  also  distinguished  by  the  number  of 
avalanches  which  fell  — 1,094  avalanches,  chiefly  between 
February  and  April,  of  which  871  (80  per  cent.)  extended  to 
forests.  On  an  area  of  3,300  acres,  2,870,000  cubic  feet  of 
timber  was  broken  and  U])rooted.  The  damage  done  by  the 
avalanches  was  valued  at  £17,220. 

In  Austria,  during  the  winter  1887-88,  damage  by 
avalanches  was  done  to  the  extent  of  £28,000. 

3.  Protective  Cidtand  Measures. 
(a)  The  surface  above  the  tree-limit  should    be   iixed    by 
sowing  grass.     In  order  to  afford  a  sufficient  obstacle  to  the 


618  I'ROTECTION    AGAINST    AVALANCHES. 

sliding  down  of  the  snow,  the  grass  should  be  mown  so  as  to 
leave  a  high  stubble. 

(h)  All  shrubs,  such  as  rhododendrons,  green  alder,  dwarf 
birch,  etc.,  should  be  preserved  carefully  on  steep  slopes. 

(c)  The  forest  must  be  maintained  up  to  the  tree-limit,- and 
this  is  the  most  important  rule.  Forests  which  serve  to 
protect  the  country  from  avalanches  are  commonly  found  in 
Switzerland  the  Tyrol,  and  the  Austrian  Alps,  and  must  be 
properly  managed  so  as  to  secure  the  object  in  view\ 

The  best  species  for  such  forests  are  Pinus  Ccmhra, 
P.  montana,  green  alder,  larch  and  spruce.  The  mountain- 
pine  and  alder  resist  the  snow  action  splendidly.  Spruce 
grows  up  to  an  altitude  of  (5,000  feet.  Beech  and  sycamore  form 
useful  mixtures  up  to  4,600  feet.  The  Selection  system  must 
be  adopted,  and  all  gaps  should  beat  once  planted  up.  When 
a  new  forest  is  being  formed,  sometimes  sowing  and  sometimes 
planting  should  be  preferred.  In  stony,  shallow  calcareous 
soils,  pit-sowings  are  made  under  the  shelter  of  stones,  rocks, 
dead  branches  stuck  into  the  ground,  or  of  logs  fixed  by  stakes, 
all  of  which  protect  against  the  sliding  of  the  snow\  In  places 
where  there  is  deeper  soil,  in  depressions,  etc.,  multiple- 
planting  with  three  and  four  plants  should  be  tried.  The  cost 
varies  from  £5  to  £8  per  acre.  Production  of  wood  is  of 
secondary  importance  in  such  forests,  and,  as  a  rule,  only 
dead  and  broken  wood  should  be  utilised,  and  the  stumps 
should  then  be  left  in  the  soil,  the  felling  being  high  above 
the  ground.  Thickets  of  young  wood  must  be  carefully 
thinned.  Neither  removal  of  litter  nor  pasture,  more  especi- 
ally that  of  the  destructive  goat,  should  be  allowed,  but, 
unfortunately,  in  such  places  browsing  by  goats  is  only  too 
common,  and  the  tree-limit  is  being  continually  lowered. 


4.  Protective   Works. 

Protective  works  consisting  either  of  ditches,  rows  of  wattle- 
fences  or  walls  should  be  made  above  and  below  the  line 
where  avalanches  begin,  which  is  easily  recognised  l)y  a 
sudden  change  in  the  gradient  of  the  slope. 

{a)  Ditches. — Interrupted  horizontal  ditches,   fi  to  16   feet 


PROTECTIVE    WORKS. 


619 


apart,  are  dug  all  over  the  area,  being  arranged  like  the 
wattle-fences  in  Fig.  281 ;  their  construction  on  very  steep 
slopes  is  evidently  not  unattended  with  danger. 


e^S;4iS^{j-i>«& 


si&^si^s-aP&Q^' 


Fig.  281. — rian  of  fences  for  protection  against  avalantlies. 
a  h.  Line  where  the  avahinches  commence,     c.   Fences. 

{}>)  lions  of  Wattle -Fence  a. — The  stakes  used  may  be  eitlier 
of  wood  or  iron.  Tliese  are  set  up  at  intervals  of  from  20  to 
50  feet,  their  central  points  being  at  those  of   a   series  of 


Fig.  282. — Dry  masonry  wall  for  protection  against  avalanches. 

equilateral  triangles  ;  they  should  be  15  to  30  feet  long,  and 
of  watlle-work  with  branches  plaited  between  stakes  jfirmly 
driven  into  the  ground. 

Such  a  system  of  wattle-fences  allows  soil  to  be  formed  on  a 


620 


PROTECTION    AOAINST    AVALANCHES. 


rock}'  slope,   which  may  afterwards  ])e  sown  with  grass,  or 
planted  with  trees  or  shrubs. 

((■)  ]]'(iUs. — On  stony  ground,  walls  of  dry  masonry  may  be 
erected  instead  of  wattle-fences;  their  mode  of  construction  is 
shown  in  Fig.  282.  On  steep  rocky  slopes,  the  rock  must  be  cut 
to  admit  the  foundation  of  these  walls,  but  this  need  only  be 
deep  enough  to  prevent  the  walls  from  falling,  owing  to  their 
own  weight.  Such  w-alls  have  proved  effective  in  the  Swiss 
cantons,  Uri,  GraubUnden  and  Wallis,  and  cost  3s.  to  6.s.  per 
cubic  meter.  Confidence  in  them  was  greatly  disturl)ed  by 
the  damage  since  1867,  done  in  1887-88. 


I'ii;. 


eai 


CHAPTER   III. 

PROTECTION    AGAINST    SHIFTING    SAND.* 

Under  the  term  slii/ting  sand  is  meant  a  tine-grained  sand 
containing  so  little  clay  or  humus  that  when  dry  and  the  soil 
is  hadly  covered  with  vegetation,  it  is  set  in  motion  by  the 
wind  and  blown  from  place  to  place.  Shifting  sand  is  generally 
found  on  the  sea-coast,  but  also  in  the  interior  of  countries. 
As  the  productive  forest  area  becomes  rapidly  reduced  by  the 
spread  of  the  sand,  the  evil  must  be  promptly  and  vigorously 
met. 

Section  I. — Sand  Dunes. 

1.  Description. 

Sand  is  thrown  up  by  the  waves  along  the  sea-coast  at  high 
tide,  and  becomes  under  certain  circumstances  heaped  up  into 
hillocks,  or  dunes,  and  is  then  carried  further  into  the  interior 
of  the  country.  Vasselot  de  Regne  states  that  the  grains  of 
sand  on  the  Gascon  coast  are  too  large  to  be  carried  like  dust 
before  the  wind,  but  are  rolled  up  the  slope  of  a  dune  and  fall 
over  its  ridges,  so  that  the  dune  naturally  attains  a  slope  of 
about  25^^  towards  the  sea,  whilst  its  slope  inland  is  generally 
steeper,  and  may  attain  60°.  The  sand  is  blown  away  from 
the  ridges  or  from  any  eminences  in  the  dune,  however  slight 
they  may  be,  and  is  also  carried  through  depressions  made  in 
a  ridge  to  the  further  side  of  the  dune.  Two  forces  are  at 
work  on  the  sand — the  sea-breeze  which  prevails  during  day- 
time and  drives  the  sand  inland,  and  the  land-breeze  by  night, 
which  finds  the  sand  firmer  owing  to  the  dew,  and  is  not  so 
effectual  in  blowing  it  back  as  the  sea-breeze  is  in  blowing  it 
forward. 

*  Wessely,  Josef,  "  Der  Eurf)paischc  Flutrsand  u.  seine  Cultur."  Wien,  1873. 
"  Notice  sur  les  Dunes  do  la  Coubre,"  par  Vasselot  de  Regno.  Paris,  Imp.  Nat., 
1878.  "  La  Dune  Littorale,"  par  C.  Grandjean.  "  Revue  des  Eaux  et  Forets." 
July — December,  1887.  Lehnpfuhl,  "  Dunenwanderung  und  Diinenwald " 
("  Muudener  Forstliche  Heft,"  2  Heft,  1892,  p.  53). 


022  I'ROTKCTION    ACAINST    SHIKTINC    SAND. 

On  the  coasts  of  the  North  Sea  and  of  the  Baltic,  in  Holstein, 
Schleswig,  Juthmd,  and  in  the  Baltic  islands,  and  along  the 
western  coast  of  France,  from  the  lie  d'Oleron  to  the  mouth  of 
the  Adour  river,  sand-dunes  cover  extensive  areas,  and  until 
efifective  measures  were  taken  to  fix  them,  large  tracts  of 
cultivated  land  were  huried  in  sand.  Along  the  coasts  of  West 
and  East  Prussia,  for  a  distance  of  150  miles,  dunes  extend  to 
a  breadth  never  less  than  one-sixth  of  a  mile,  and  unless  they 
are  fixed  they  encroach  inland  yearly  by  50  feet.  The  area  of 
European  dunes  is  estimated  at  21,000  square  miles. 

The  coasts  of  the  British  Isles  consist  chiefly  of  rocky  cliflfs, 
but  sand-dunes  are  found  in  Norfolk,  Somersetshire,  Lanca- 
shire, Elgin  and  other  places  along  the  coasts  of  Great  Britain. 

The  dunes  along  the  Bay  of  Biscay  in  the  French  Dcparte- 
meiits  des  Landes  et  de  la  Gironde  extend  over  a  total  length  of 
140  miles,  forming  a  series  of  parallel  ranges  about  160  feet 
high  and  4  miles  broad.  During  the  constant  political  troubles 
of  the  middle  ages,  the  natural  forests  of  maritime  or  cluster 
pine  (P.  Pinaster,  Soland.),  which  formerly  covered  this  area, 
were  burned  and  destroyed,  and  the  sand  invaded  the  country 
at  the  rate  of  60  to  70  feet  annually,  covering  whole  towns  and 
villages,  cultivated  fields,  and  vineyards.  The  passage  of 
watercourses  to  the  sea  was  interrupted  by  the  accumulated 
sand  ;  a  desolate  malarious  region,  called  Les  Landes,  resulted. 
Swamps  and  lagoons  of  brackish  water  alternated  with  vast 
tracts  of  arid  sandhills,  where  a  few  sheep  pastured,  tended 
by  shepherds  on  stilts. 

In  1787,  the  engineer  Br6montier  published  a  treastise 
showing  that  the  dunes  could  be  fixed  by  sowing  sand-grasses 
and  pines,  and  the  work  of  fixing  the  dunes  of  Gascony  was 
commenced  in  1788,  and  has  been  continued  with  complete 
success  up  to  the  present  day.  In  1810,  the  French  Legisla- 
ture passed  an  Act  enabling  the  State  to  fix  dunes  belonging 
to  municipalities  and  private  owners,  by  means  of  plantations, 
the  owners  only  recovering  their  property  after  paying  the 
cost  of  fixing  the  sand.  This  they  have  only  rarely  been  able 
to  do,  owing  to  the  great  cost  of  the  operation  compared  with 
the  value  of  the  reclaimed  land. 

About  800,000  acres  have  thus  been  dealt  with,  the  annual 


SAND    DUNES. 


62  ;i 


charge  for  new  work  and  for  maintaining  the  dunes  which  have 
been  ah-eady  fixed  having  been  ^.'8,400  in  1893.  In  this  way 
vast  areas  have  been  saved  for  agriculture,  and  enormous 
tracts  of  pine-forests  created,  which  afford  work  to  a  large 
number  of  people  in  the  extraction  of  resin  and  turpentine 
from  the  trees,  and  in  timber-works,  the  pine-forests  of  the 
Landes  now  exporting  about  600,000  tons  of  pit-timber  to 
Great  Britain  annually,  besides  large  supplies  of  timber  and 
firewood  for  local  use. 

2.  Construction  of  a  Littoral  Dune. 

As  an  embankment  along  the  coast  prevents  the  wind  from 
driving  the  sand  inland,  the  chief  point  to  be  secured  is  to  fix 


c.  The  Ferret  Duue. 
Fig.   284. 

the  sand,  so  as  to  form  what  is  termed  the  littoral  dune,  the 
mode  of  construction  of  which  is  as  follows : — 

Two  parallel  fences  are  erected  along  the  coast,  between  and 
on  both  sides  of  which  the  sand  accumulates,  the  fences  being 
gradually  raised  till  the  dune  has  attained  such  a  height  that 
only  inappreciable  quantities  of  sand  are  blown  over  it. 

The  fence  facing  the  sea  is  a  continuous  line  of  paling,  from 
300  to  GOO  feet  distant  from  high-water  mark  ;  it  is  made  of 
inch  planks  (j\  feet  long,  6  to  8  inches  wide,  which  are  pointed 
below.  They  are  inserted  to  |]ths  of  their  length  into  the  sand, 
and  1  inch  apart,  to  allow  sand  to  blow  through.  When  the 
sand  has  nearly  covered  tiie  planks,  they  are  raised  three  feet 


H2i  PROTECTION    AOAINST    SHIFTIN(4    SAND. 

by  means  of  levers  worked  by  one  man  against  the  next  un- 
raised  plank,  or  by  a  stout  rod  passed  through  a  chain  fastened 
round  the  plank  and  lifted  by  two  men.  This  operation  is 
repeated  until  the  proper  height  of  the  dune  is  attained,  which 
Grandjean  places  at  10  metres,  or  about  33  feet. 

The  back  fence  is  usually  made  of  wattle-work  and  prevents 
the  sand  which  has  passed  through  the  front  fence  from  being 
carried  inland,  and  gives  a  proper  contour  to  the  dune.  This 
fence  is  replaced  by  a  new  one  when  it  has  become  covered 
with  sand. 

The  preceding  diagrams  (Fig.  284)  taken  from  Grandjeans' 
work  represent  the  ordinary  sections  of  the  littoral  dune,  and  he 
considers  J>  and  c  preferable  to  a,  as  being  much  easier  to 
maintain.  They  have  slopes  of  26'^  or  27°  facing  the  sea,  which 
corresponds  with  De  Piegn6's  natural  slope  of  the  dunes. 
Grandjean,  in  the  work  already  referred  to,  gives  full  and 
satisfactory  reasons  for  the  height  and  gradient  he  prefers  for 
the  littoral  dune. 


3.  Material  for  FixiiKj   the  Sand. 

The  littoral  dune  can  never  be  planted  with  trees,  on  account 
of  the  salt  spray  of  the  waves  and  the  strong  sea-wind.  In 
certain  places  in  Holland,  masonry  works  and  piles  have  been 
erected  to  protect  the  dune,  but  as  a  rule  flexible  plants  are 
much  more  effective  than  rigid  and  costly  works.  Attention  is 
therefore  directed  to  sand-grasses  and  sedges,  and  the  best  of 
these  for  the  purpose  are : — 

Sea  marram,  or  matweed  {Psamma  arcnaria,  K.  &  S.) ; 

Baltic  matweed  {P.  haltica,  Schrad.)  ; 

Sand  lyme-grass  {Elymus  arenarins,  L.)  ; 

Sand  sedge  {Carex  arcnaria,  L.). 

All  these  plants  are  characterised  by  very  long,  much-divided 
rhizomes,  and  can  withstand  being  covered  over  and  buried  in 
sand.  The  sea  marram  will  grow  only  where  it  is  continually 
covered  with  fresh  sand,  and  dies  inland  in  the  shelter  of  the 
littoral  dune,  when  no  fresh  sand  covers  it.  It  is  termed 
gourbet  in  France,  and  is  exclusively  used  for  fixing  the  littoral 
dune  along  the  Bay  of  Biscay.     Next  to  the  marram  in  repute 


SAND    DUNES.  625 

for  fixinf^  the  sand  comes  the  lyme-grass,  and  these  two  species 
'are  chiefly  used  for  the  purpose  in  Holland. 

Other  plants  grow  in  gradually  among  them  ;  at  first  lichens 
and  algae,  then  grasses,  as  for  instance  Arenaria  iJeploides,  L., 
Aira  canescens,  L.,  couch-grass  {Agropyrum  repens,  Beauv.), 
and  other  plants,  such  as  the  sea-poppy,  Glaucium  luteiun, 
Scop.;  Lathijrus  maritimus,  Bigel;  and  Hieracium  nmhellatum, 
L.,  etc.  Vasselot  de  Eegne  gives  a  very  complete  botanical 
list  of  dune  plants. 

Several  shrubs  then  appear  on  the  land  side  of  the  dune,  as 
Salix  repens,  L. ;  sea-buckthorn  {Hippirphae  rhnmnoides,  L.) ; 
Li/riion  hdrJxinini,  L.  ;  Tamarix,  etc. 

4.  MaiiiteiKincc  of  the  Littoral  Dune. 

When  once  the  littoral  dune  has  been  raised  to  a  proper 
height  and  profile  and  fixed  by  means  of  sea  marram,  it  is 
necessary  to  maintain  it  constantly  in  the  same  state  ;  any 
undue  accumulation  of  sand  in  any  part  of  the  sea  side  of  the 
dune  at  once  causes  an  inland  draught  of  sand  on  both  sides  of 
it,  which  if  not  at  once  attended  to  will  breach  the  dune. 

Men  termed  gardes  cantonniers  are  therefore  stationed  along 
the  littoral  dune  in  Gascony,  who  cut  away  all  vegetation  except 
the  marram  from  its  surface  facing  the  sea,  in  order  to  prevent 
undue  accumulation  of  sand.  As  the  marram  grows  readily 
from  cuttings  during  the  colder  six  months  in  the  year,  the 
workmen  who  cut  it  away  from  ridges  plant  it  in  depressions, 
or  if  the  season  be  too  hot  or  dry  for  the  cuttings  to  take  root, 
the  pieces  cut  from  ridges  are  merely  placed  on  depressions. 
In  this  way,  by  cutting  away  the  marram  where  it  is  too  dense, 
and  planting  or  j^lacing  it  in  depressions,  the  proper  contour 
of  the  dune  is  maintained,  as  the  sand  accumulates  behind  the 
marram,  and  is  blown  away  wherever  the  latter  is  cut. 

In  cases  where  the  dune  has  been  neglected  and  large 
depressions  have  been  formed,  it  may  be  necessary  to  use 
wattle  fencing  to  cause  an  accumulation  of  sand,  but  if  ordinary 
care  be  taken,  the  marram  grass  will  suffice  to  keep  the  littoral 
dune  in  good  condition,  and  Grandjean  believes  that  new 
littoral  dunes  may  be  formed  by  means  of  it,  without  using  the 
fences  described  in  section  3. 

F.P.  S  S 


626  PROTECTION    AGAINST    SHIFTING    SAND. 

5.  Protective  Coast  Forest  Zone,  wider  the  Shelter  of 
the  Littoral  Dune. 

a.  Desrriplion. 

Under  the  shelter  of  the  Httoral  dune,  a  protective  zone 
of  various  woody  si)ecies  mixed  with  gorse,  species  of  genista, 
heather,  Tamarix,  etc.,  is  then  allowed  to  spring  up,  but  is 
generally  planted  or  sown  artificially. 

The  species  chiefly  grown  near  the  Baltic  coast  is  the  .Scots 
pine,  over  8,000  acres  of  this  species  having  l)een  phinted  near 
Dantzig  between  1795  and  1850. 

In  Zealand,  the  imcinata  variety  of  the  mountain-pine 
{Pinus  montana,  Mill.)  has  been  used,  and  its  great  success  is 
due  to  its  indifference  to  soil  and  climate,  and  its  habit  of 
retaining  its  lower  branches  green  for  long  periods.  In  France 
the  cluster  pine  is  chiefly  used,  but  it  is  liable  to  be  frozen  when 
grown  too  far  to  the  north. 

Spruce,  birch,  or  white  alder  may  be  mixed  with  the  pines, 
and  in  South-west  France  pedunculate  oaks  and  Q.  Tozza, 
D.C.  In  depressions,  the  common  alder,  poplars,  and  willows 
may  be  grown. 

The  different  varieties  of  Pinus  Laricio,  Poir.,  and  especially 
the  Corsican  variety,  maples  and  the  silver  poplar,  are  well  able 
to  withstand  the  force  of  the  strong  sea-winds. 

As  a  rule,  the  growth  of  protective  forests  near  the  sea  coast  is 
poor,  on  account  of  the  strength  of  the  sea  breeze  and  the  poor 
nature  of  the  sand  in  which  the  trees  grow,  and  which  is  being 
constantly  heaped  over  their  roots,  but  protection  and  not  timber 
is  required  in  a  zone  extending  from  600  to  2,000  feet  beyond 
the  littoral  dune,  and  which  if  left  un planted  would  be  a  bare 
sandy  tract  tending  to  spread  inland  and  ruin  existing  forests. 

In  a  coast-protection  forest,  short  terminal  shoots,  procum- 
bent stems,  one-sided  crowns  and  a  leaf-canopy  sloping  down 
seawards,  are  evidences  of  the  struggle  these  woods  carry  on 
with  the  wind,  but  it  is  a  forest  all  the  same. 

The  conditions  of  growth  greatly  improve  as  the  distance 
from  the  sea  becomes  greater,  so  that  further  inland,  especially 
if  the  sand  contains  little  flakes  of  mica,  even  superior  species 
such  as  beech  or  silver-tir  may  be  grown,  as  in  Alsensund 


■      SAND    DUNES.  627 

in  Schleswig.  If,  in  any  part  of  the  protected  zone,  a  shelving 
cHflf  of  sand  unprotected  by  vegetation  is  exposed  to  the  wind ; 
it  should  be  covered  with  branches  of  pine,  gorse,  broom,  etc., 
placed  like  slates  on  a  roof,  and  some  sand-fixing  grass  sown 
to  prevent  the  sand  from  being  carried  inland. 

h.  Method  of  Formation, 

The  inequalities  of  the  ground  should  first  be  levelled  in  order 
to  afford  the  wind  as  few  points  of  attack  as  possible.  Sand- 
fixing  grasses  should  then  be  sown  or  planted,  the  former 
method  being  followed  in  France  and  the  latter  in  Germany, 
Pieces  of  the  grasses  should  be  planted  in  rows  at  right  angles 
to  the  direction  of  the  prevalent  wind,  holes  being  made  with 
a  spade  1  foot  to  2  feet  apart,  and  three  or  four  pieces  of  rhizome 
planted  in  each  hole  so  deeply  that  only  about  6  inches  of  them 
appear  above  the  sand.  They  soon  sprout  and  send  out  suckers 
in  all  directions  through  the  sand,  which  they  fix  most 
effectually. 

The  cost  of  fixing  sand  with  grass  is  that  of  70  to  140  days' 
work  at  3s.  a  day,  averaging  ;£15  an  acre.  In  Prussia,  long- 
rooted  yearling  pines  are  then  planted  1  foot  apart  in  rows 
distant  3  feet  from  one  another.  The  work  is  done  with  an 
iron  dibble,  so  as  not  to  loosen  the  sand  unnecessarily.  Moun- 
tain-pine is  the  best  species  in  the  north  for  fixing  the  sand, 
other  trees  being  eventually  planted  between  the  pines. 
Cuttings  of  poplars  or  willows  may  be  also  planted. 

In  fixing  dunes  along  the  Baltic  coast,  Prussia  spent  s63,100 
a  year  between  1884  and  1887,  during  which  time  230  acres 
were  fixed  with  grass  and  608  acres  stocked  with  trees.  This 
is  now  being  Continued  at  an  annual  cost  of  .4'5,000. 

The  planting  is  usually  effected  under  the  protection  of  the 
littoral  dune,  and  pine  forests  in  the  protective  zone  are 'then 
managed  under  the  Selection  system,  and  broadleaved  species 
are  coppiced. 

In  the  Danish  island  of  Zealand,  up  to  1866,  sowing  was  pre- 
ferred to  planting,  the  sand  being  previously  covered  with  a 
thin  coating  of  loam  which  was  placed  on  the  ground  in  heaps 
in  the  autumn,  and  somewhat  weathered  by  the  winter's  frost 
before  being  spread  over  the  area  in  tbe  spring. 

S  s  2 


628 


PROTECTION    AOAINST    SHIPTINO    SAND. 


In  France  tlie  cluster  pine  is  sown  with  other  seeds  in  the 
following  proportion  for  an  acre  : — 

Cluster  pine  seed ,         .         .         .26     lbs. 
Furze  or  gorse      .         .         .         .     2h     „ 

Genista 2i     ,, 

Marram  grass        .         .         .         .     2^     „ 
Seeds  to  attract  insectivorous  birds     2^     ,, 
As  the  seed  is  sown,  it  is  covered  with  1,000  faggots,  3  feet 
in  girth  and  5  feet  long  per  acre  of  furze,  broom,  heather  or 

pine  branches,  furze  being 
preferred  wherever  it  is 
available.  The  faggots  are 
evenly  distributed  over  the 
area  and  opened  out,  and 
the  sowing  is  then  com- 
menced on  the  land  side 
towards  the  littoral  dune 
under  protection  of  a 
wattle  -  fence  intended  to 
keep  off  the  sand  blown 
back  by  the  land  breeze. 
Each  row  of  seed  is  covered 
by  the  branches,  which  are 
placed  in  rows  with  their 
lower  ends  towards  the  sea, 
so  that  each  succeeding  row 
of  branches  partly  covers 
the  preceding  one,  being 
arranged  like  slates  on  a 
roof  and  kept  steady  by 
spadefuls  of  sand  thrown  on  them  at  intervals  of  2  feet. 

Areas  of  about  300  feet  long  by  60  feet  broad  are  thus  sown 
at  one  time.  Between  1862  and  1874,  5,200  acres  were  thus 
sown  in  the  Gironde  at  a  cost  of  .^30,646. 


Fife.  -85. — Psamma  armaria, 
a  h  Surface  level  of  ground,     c 


IJeauv. 
Rhizomes. 


r.   Tcndnuj  the   Woods. 

The  sand  grasses  used  in  fixing  the  dunes  must  not  be  cut 
or  pastured.  The  water  rat  and  the  larvae  of  Poli/phi/llafullo, 
L.,  are  the  most  dangerous  enemies  to  the  grass  rhizomes. 


SAND    DUNES. 


629 


Dune  forests  must  be  strictly  protected  against  grazing, 
removal  of  litter  and  trespass.  Article  366a  of  the  German 
Criminal  Code  punishes  contravention  of  police  regulations 
regarding  dune  forests  with  fines  up  to  i'7  lO.s.,  or  imprison- 


Fig.  286.  —  Elijmits  arena ri us,  L. 

ment,  and  in  Holland,  four  weeks'  imprisonment  is  inflicted 
for  cutting  grass  on  dunes. 

Only  dead  or  dying  wood  should  be  removed  from  the  dune 
forests. 

(1.  Adtleniht. 
Tiie  best  English  example  of  the  fixing  of  shifting  sands 
is  on  the  Holkham  sand-hills,  on  the  Norfolk  coast,  belonging 
to  the  Earl  of  Leicester,  where,  since  1850,  sea  lime-grass  and 
marram  have  been  used  to  fix  the  sands,  and  several  species  of 
pine  planted,  of  which  the  Scots  and  Austrian  pines  have 
proved  most  successful.  The  trees  are  planted  widely,  as 
thinnings  would  be  injurious,  unless  lop  and  top  were 
removed,  owing  to  danger  from  tire.  Now  that  the  grass 
is  kept  down  Ijy  the  trees,  fires  are  rare.  Extensive  planting 
of  sand-hills  has  also  been  done  in  South-west  Lancashire, 
Scots,  Austrian  and  Corsican  pines,  as  well  as  alder,  birch, 
tamarisk  and  other  plants,  being  used.  Rabbits  are  the  chief 
danger  to  these  plantations,  being  very  common  on  sancLhills 
along  the  coasts  of  Great  Britain,  Unless  they  are  extermi- 
nated, there  is  little  hope  of  fixing  the  sand. 


()3()  IMIOPKCTION    AGAINST    SHIFTING    SAND. 

Ill  India,  along  the  Madras  coast,  extensive  plantations  of 
Casiiarina  equisetiJoUd,  Forster,  have  been  made,  and  grow 
with  extraordinary  rapidity,  yielding  excellent  fuel. 

In  the  Cape  Colony,  shifting  sands  are  sown  with  cluster 
pine  and  Acacia  Pycnantlia  and  dccurrens,  the  seed  being  mixed 
with  rye  seed,  as  the  rye  protects  the  seedlings.  A  layer  of 
town  refuse  is  first  spread  over  the  sand  to  assist  in  fixing  it 
and  serve  as  manure,  ten  tons  to  three  acres  of  sand. 
Cuprcssiis  macrocarpa,  Gord.,  and  Pinus  Halepensis,  Mill.,  do 
well,  also  robiniq.. 

Section  II. — Inland  Sand.* 

1.  Description. 

Inland  sandy  tracts  generally  originate  from  sandy  hills,  and 
are  due  chiefly  to  the  clearance  or  careless  management  of 
forests,  and  especially,  to  removal  of  litter.  Extensive  sheep 
pasture  on  heather-land  also  readily  sets  sand  in  motion. 
Large  tracts  of  shifting  sands  are  found  in  Hannover, 
Oldenburg,  Pommerania,  etc.  The  greatest  areas  in  Europe 
of  inland  shifting  sand  are,  however,  in  Hungary  and  South 
Piussia. 

2.  Protective    Rules. 

Maintenance  of  forests,  especially  on  sandy  hills,  is  the  chief 
protective  measure  to  be  adopted.  Not  only  must  clearances  of 
forests  be  prevented,  but  all  destructive  practices  leading  to 
their  impoverishment  must  be  stopped. 

The  following  measures  should  be  adopted  in  forests  which 
serve  as  a  protection  against  shifting  sand : — 

(a)  The  Selection  system  should  be  adopted,  or  only  very 
small  areas  under  a  short  rotation  be  cleared.  Extensive 
clearings  must  be  avoided  in  any  case,  but  the  shelter-wood 
systems  with  natural  regeneration  would  be  suitable  were  it 
always  possible  to  obtain  natural  regeneration  on  dry,  sandy 
areas.  In  the  Gascon  cluster-pine  forests-,  clear-cutting  is 
adopted,  as  the  trees  that  form  the  final  crop,  being  tapped 
for  resin,  do  not  produce  seed.     The  pine  seed  is,  however, 

•  r.mklKiidt,  Kr.  11.,  '•Zur  Kullur  lies  Klugsaiulcs,"  "Aiisdeni  Waldr,"  1S77, 
1..  107. 


INLAND    SAND.  631 

produced  so  abundantly  by  trees  adjoininjc;  the  cleared  area 
and  germinates  so  freely,  that  good  results  follow. 

(b)  In  the  case  of  artificial  regeneration,  and  for  filling  up 
natural  regeneration,  planting  is  preferable  to  sowing,  but  the 
planting-holes  should  be  small,  and  young  plants  used. 

{(■)  The  borders  of  the  forest  to  windward  must  be  kept 
densely  stocked  and  all  underwood  protected,  while  the  soil- 
covering  is  strictly  preserved. 

{(I)  Stumps  should  be  left  in  the  ground  after  fellings,  and 
cultivation  of  cereal  crops  in  combination  with  sowings  of 
forest  trees  must  not  be  undertaken. 

(c)  No  pasturage  should  be  allowed,  and  all  servitudes  for 
pasturage,  passage  of  cattle,  usage  of  grass  or  litter  should  be 
legally  annulled. 

3.  Fixation  of  the  Sand. 

Tlie  supply  of  sand  must  be  stopped  at  its  origin  by  planting 
up  the  sandy  hills  from  which  it  comes.  Loose  sand  may  be 
fixed  by  means  of  fences,  or  by  covering  it  with  branches  or 
sods,  and  both  these  methods  may  be  combined.  Planting  sand- 
grasses  is  not  advisable,  as  it  only  increases  tbe  difficulty  of 
restoring  forest  growth  to  the  denuded  area. 

a.  Fences. 

Fences  are  generally  made  by  driving  into  the  ground  pine 
stakes  6  to  8  feet  long  and  2i-  to  4  inches  in  diameter.  They 
should  be  driven  2  to  3  feet  deep  and  supported  alternately 
on  either  side  by  means  of  oblique  stakes,  as  shown  in 
Fig.  287. 

Between  the  stakes,  branches  of  Scots  pine  or  of  broom 
should  be  intertwined,  leaving  sufficiently  large  interstices  for 
the  sand  to  pass  through,  or  else  the  fence  would  be  broken  by 
its  pressure.  Poplar-  or  willow-cuttings  may  be  used  instead 
of  pine-stakes ;  they  take  root,  and  their  side-shoots  may 
eventually  be  twined  into  a  fence. 

The  fences  should  run  at  right  angles  to  the  direction  of  the 
shifting  sands,  on  both  sides  of  roads,  or  other  endangered 
places,  their  ends  being  turned  round  to  serve  as  a  protection 


632  PROTECTION    AOATNSST    SHIFTING    SAND. 

against  the  winds  IjFowing  at  right  angles  to  the  fences.  Several 
of  these  horseshoe-shaped  fences  may  be  made,  at  suitable 
distances,  parallel  to  one  another,  the  distance  between  them 
depending  on  the  locality ;  on  level  ground  a  fence  will  afford 
shelter  for  200  to  230  feet,  but  on  hilly  ground  for  not  more 
than  half  these  distances,  and  on  steep  hill-sides  not  more 
than  60  feet. 

One  man  can  make  from  GO  to  6G  feet  of  fencing  in  a 
day,  non-inclusive  of  the  labour  of  transporting  the  material. 
Fence-construction  is  therefore  costly,  and  fences  are  not  used 
at  present  so  much  as  formerly,  as  they  do  not  thoroughly 


Fig.  287. 

fulfil  their  object.  In  general,  the  formation  of  protective 
fences  is  now  not  followed,  as  they  are  expensive  to  erect,  and 
the  results  are  not  considered  sufficiently  good. 

b.  Cover  ill  !i  the' Sand, 

Before  covering  the  sand,  all  unevennesses  on  the  area  should 
be  smoothed  down.  The  wind  acts  with  more  force  on  rough 
projections  in  the  sand  ;  and  the  steeper  the  hillocks,  the  more 
readily  does  the  sand  roll  down  them.  Small  depressions 
should  be  filled  up  with  brushwood  or  wattle-work. 

Branches,  weeds,  giass,  seaweed,  and  sods  or  straw  are  the 
materials  used,  and,  for  the  sake  of  economy,  the  nearest 
available  material  should  be  chosen.  Branchy  stems  of  Scots 
pine,  juniper-bushes,  heather,  broom,  reeds  or  rushes  form 
useful  material,  and  sods  are  cut  from  grass  or  heather  land. 

Covering  the  ground  with  sods  is  the  best  method,  and  is 
much  followed  in  Hannover  and  Oldenburg,  whilst  straw  is  used 


INLAND    SAND. 


633 


in  Flanders.  The  covering  is  chiefly  employed  for  the  most 
endangered  places,  such  as  ridges,  the  windward  side  of  hills, 
depressions  and  roads ;  other  places  may  be  readily  stocked 
with  forest  growth,  provided  fresh  sand  is  not  blown  on  to 
them. 

The  covering  should  then  be  applied  from  W.  or  S.W.  to  E. 
or  N.E.,  the  ground  being  either  entirely  or  partially  covered. 
Eoads  are  generally  covered  completely,  but,  in  other  cases, 
partial  covering  is  adopted  on  account  of  the  high  cost  of 
complete  covering.     The  looser  the  sand  the  more  complete 


.  \ !      1 

i  I     i 


L 


J     J 


fc., 

PK 

^^ 

_j 

i. 

' 

■„:  ^  ; 

.1 

,.■:  u 

"^ 

pi 

u 

J 

U     ' 

J 

J 

Fig.  288. 


1[I     w 


should  be  the  covering,  and  it  is  alwa3's  more  prudent  to  do  too 
much  than  too  little  in  this  respect. 

Jjranches  are  either  placed  on  the  surface  of  the  ground,  or 
stuck  into  the  sand,  with  the  bushy  end  inclined  away  from 
the  wind,  the  rows  partially  covering  one  another,  but  their 
use  is  not  recommended  on  account  of  the  difficulty  in  stocking 
an  area  which  has  been  completely  covered  with  branches, 
whilst  if  they  are  isolated,  they  are  liable  to  be  blown  away. 

Heather  sods  can  be  used  only  on  level  ground  in  pieces 
ll  to  2i  feet  long,  and  should  be  tossed  equably  over  the  area 
by  means  of  hay-forks,  after  it  lias  been  sown  up  with   Scots 


r>«4  PROTECTION    AGAINST    SHIFTINC    8ANU. 

pine  seed.  In  the  Osnabnrg  heath,  about  twelve  waggon-loads, 
with  two  horses,  of  heather  per  acre,  are  required,  and  the  cost 
is  i^l  12s.  per  acre.  Sowings  thus  carried  out  will  generally 
prove  successful  if  the  spring  he  moderately  wet. 

Sods  are  always  laid  with  the  earthy  side  downwards,  and 
should  he  firmly  pressed  down. 

The  diagrams  on  the  previous  page  show  how  the  sods  may  be 
arranged.  Where  a  sod  is  laid  in  the  middle  of  each  patch,  it 
should  be  larger  than  the  others,  and  that  form  of  sodding  is 
preferable,  as  the  loose  sand  wilhin  the  patches  cannot  get  out. 
The  lines  of  sods  should  be  at  right  angles  to  the  direction  of 
the  prevailing  wind.  The  work  of  sodding  should  be  done 
during  autumn,  after  the  sand  has  been  well  soaked  by  rain,  or 
in  the  spring,  and  the  ground  should  be  at  once  sown  or  planted. 

In  Germany,  partial  sodding  of  the  ground  costs  from  .^1  to  £3 
an  acre,  with  daily  labour  at  l.s.  10(/.  Covering  with  branches 
takes  about  forty  or  fifty  cartloads  per  acre,  and  costs  somewhat 
less  than  sodding. 

4.  Stocking  ihe  Area. 

Fixing  the  sand  should  be  followed  by  stocking  the  area, 
unless  the  two  operations  have  been  done  simultaneously,  or 
the  stocking  precede  the  covering,  as  is  the  case  when  branches 
or  heather  are  used. 

The  most  suitable  species  are  Scots  or  mountain  pines. 
These  species  are  very  hardy,  and  yield  plenty  of  humus. 
The  mountain  pine,  owing  to  its  creeping  habit,  covers  the 
ground  admira])ly.  Among  exotics  in  West  Prussia,  Pin  its 
rigida,  Mill.,  and  P.  BankHiana,  LI.,  either  pure  or  mixed 
with  Weymouth  pine,  have  given  excellent  results. 

Of  broadleaved  trees,  the  robinia,  owing  to  its  faculty  of 
producing  suckers  rapidly,  fixes  the  sand,  and  has  proved 
successful  in  Hungary.  For  damp  places,  poplars  and  willows 
should  be  used,  the  Canadian,  white  and  black  poplars  being 
most  usual.  Salix  urenaria,  L.,  the  Caspian  willow  {S.  acnti- 
folia,  Willd.),  S.  longifolia,  Host.,  or  S.  cinerca,  L.,  may  also 
be  planted,  the  latter  rapidly  covering  the  soil  with  its  creeping 
lateral  branches,  and  it  easily  grows  through  any  sand  which 
may  be  blown  over  it. 


INLAND    SAND.  635 

In  South  Russia,  near  Odessa,  Ailanthus  glandulosa,  Desf.,  is 
used  on  sand-dunes,  and  also  in  the  south  of  France.  This 
very  accommodating  species  grows  rapidly  and  sends  out 
numerous  suckers,  and  thrives  on  the  hot  southern  slopes  of 
the  Siwalik  Hills  in  India,  as  well  as  in  smoky  London.  The 
cluster  pine  may  also  be  used,  as  in  Gascony,  but  it  is  not  very 
frost-hardy.  Sowing  is  still  employed  in  restocking  bare  sandy 
tracts  in  France,  15  to  20  lbs.  of  seed  being  used  per  acre  ; 
but  in  Germany,  3  to  4-year-old  transplants  with  balls  of  earth 
are  now  planted  in  rows  at  right  angles  to  the  prevailing  wind. 
The  plants  are  put  in  deeply  to  prevent  exposure  of  the  roots, 
and  because  they  suffer  in  summer  from  the  heating  of  the 
sand.  Scots  pines  do  not  suffer  at  all  from  this  deep  planting. 
In  order  to  get  the  area  stocked  as  soon  as  possible,  intervals 
of  only  2^  to  3  feet  are  left  between  the  rows,  and  the  plants 
are  1  to  1^  feet  apart  in  the  rows.  In  Hannover,  they  are 
planted  with  a  heavy  planting  iron,  termed  Buttlar's  iron,* 
and  a  mixture  of  f  peat  with  2  per  cent,  unslaked  lime  and  ^ 
sand  is  used  to  fill  the  holes  round  the  roots.  The  peat  is 
hygroscopic  and  retains  moisture  near  the  plants'  roots. 

Eobinias,  poplars  and  willows  are  put  in  as  cuttings  in  little 
clumps,  or  in  furrows.  Sometimes  the  ground  is  cultivated 
before  the  cuttings  are  put  in,  and  Scots  pine  seed  sown  in  the 
depressions.  Hubert  recommends  that  grass  seed  should  be 
strewn  over  the  plantations.  In  Austria,  Jerusalem  artichokes 
{Hd'uuitlius  tuhcrosua)  are  frequently  planted  to  shelter  the 
woody  plants  against  heat  and  cold. 

In  case  the  sandy  tract  is  so  extensive  that  it  cannot  be  con- 
veniently planted  up  in  one  year,  a  plan  of  operations  extending 
over  a  series  of  years  sbould  be  drawn  up.  A  commencement 
should  then  be  made  on  the  windy  side  of  the  area,  and  the 
cultivation  carried  on  in  Strips  under  shelter  of  the  first  year's 
work.  In  the  Landes  of  Gascony,  shelter-fences  are  erected 
to  the  leeward  of  each  year's  strip  to  protect  the  plants  from 
sand  blown  back  by  land  breezes.  Whenever  the  work  is 
thus  gradually  done,  great  care  must  be  taken  to  fill  up  all 
gaps  in  the  areas  to  windward  before  commencing  the  work 
beyond  it. 

*    \  ide  ychlich'd  "  Aliinuiil  of  Forestry,"  Vol.  11.,  p.  124. 


636  proi'p:ction  acjainst  shifting  sand. 

At  Lingen,  in  Hannover,  work  has  been  carried  out  gradually 
since  1818,  when  there  were  3,327  acres  to  be  stocked,  of  which 
75  per  cent,  was  shifting  sand,  and  the  balance  cultivated  land. 
Between  1818  and  1832,  2,279  acres  had  been  planted  success- 
fully, and  the  balance  of  1,048  acres  was  fairly  well  stocked  by 
1837,  the  total  cost,  up  to  1832,  being  i^l  18s.  an  acre. 

Forests  on  shifting  sand  must  be  managed  most  carefully. 
Pines  are  regenerated  under  the  Selection  or  Strip  systems, 
and  broadleaved  species  by  coppice.  No  pasture  or  removal 
of  litter  can  be  allowed. 

An  interesting  account  of  the  planting  of  shifting  sands 
near  Dresden,  in  Saxony,  written  in  1894:  by  Mr.  A.  M.  Reuther, 
Conservator  of  Forests,  India,  is  here  appended. 

"  A  considerable  area  situated  within  the  Dresden  Forest 
Circle  has  for  many  years  been  leased  by  the  Military 
Department  with  the  object  of  providing  parade-grounds  for 
the  cavalry  and  infantry  regiments  stationed  there.  In  1867, 
it  was  decided  to  extend  the  parade-grounds,  for  which  purpose 
a  further  area  of  100  hectares  was  included  in  the  lease ;  and, 
in  order  to  obviate  payment  of  compensation,  the  Military 
Department  allowed  the  tree-stumps  to  be  extracted,  and  the 
litter  to  be  removed  from  this  area  after  the  forest  on  it  had 
been  clear-felled. 

"The surface  configuration  of  this  area  is  undulating, and  the 
soil  consists  mostly  of  pure  sand,  containing  here  and  there  an 
admixture  of  clay,  up  to  18  or  19  per  cent.  Very  soon  after 
the  complete  exposure  of  the  soil,  the  sandy  surface  began  to 
grow  unstable,  and  already  in  1870  tlie  shifting  sand,  moved 
by  the  wind,  covered  not  only  the  adjacent  cavalry  parade- 
ground,  but  also  blocked  the  more  distant  Konigsbrlicker 
Chauss6e  to  such  an  extent  as  to  interrupt  all  traffic  on  it.  In 
the  next  few  years  the  evil  assumed  such  large  proportions 
that  it  was  found  absolutely  necessary  to  reafforest  the  area 
with  the  least  possible  delay. 

"  Operations  were  commenced  in  1874  by  covering  the  whole 
area  with  a  network  of  wattled  fencing.  Strong  stakes,  3  to 
4  inches  in  diameter,  were  driven  into  the  ground  2  feet  apart, 
in  rows  1  chain  apart  running  south  to  north,  and  interwoven 
with  branches  of  Scots  pine,  the  wattled  fencing  thus  formed 


INLAND    SAND.  637 

being  2f  feet  high.  At  right  angles  to  these  lines  of  fencing 
similar  fences  were  made,  about  50  yards  apart,  and  2  feet  high. 
Towards  the  west,  where  the  general  surface  elevation  is  higher 
and  exposed  mounds  and  ridges  exist,  the  fences  were  placed 
closer  together  than  on  the  more  sheltered  east  side,  so  that 
the  average  area  of  each  rectangle  enclosed  by  the  fences  was 
about  1  rood  on  the  west,  and  about  2  roods  on  the  east  side. 
The  shifting  of  the  sand  was  thus  greatly  reduced,  and  restricted 
within  the  enclosures  ;  and  already  in  1875  it  became  possible 
to  begin  planting.  In  that  year  birch  and  alder  were  planted 
in  rows  along  the  fences  (on  the  sheltered  side),  the  planting 
holes  being  filled  with  good  soil  brought  from  a  distance  ;  and 
in  the  following  year  planting  up  of  the  interior  of  each 
rectangle  was  begun  with  Scots  pine  plants  1  to  2  years  old, 
which  were  put  out  in  squares  with  the  aid  of  Buttlar's  plant- 
ing tool,  3,200-  plants  being  used  per  acre,  and  each  plant 
supplied  with  a  handful  of  good  humus  soil.  The  compost 
was  prepared  in  autumn,  and  left  lying  in  heaps  during  the 
winter,  and  conveyed  to  the  site  of  the  plantation  just  before 
the  planting  season  in  spring. 

"  The  results  are  quite  satisfactory  in  so  far  as  the  ground  is 
now  fully  stocked,  and  the  surface  soil  completely  consolidated. 
But  owing  to  the  dryness  and  poverty  of  the  soil,  the  growth 
of  the  plants  is  in  many  places  very  miserable,  many  of  the 
Scots  pines  being  only  1  yard  high,  though  already  15  to  18 
years  old.  The  average  height  is,  however,  about  16  feet,  and 
for  the  most  part  the  plants  have  closed  overhead.  The  entire 
area  has  been  most  carefully  protected  ;  cattle  have  been 
strictly  excluded,  and  grass  cutting  disallowed,  and  all  un- 
authorised persons  have  been  prohibited  from  walking  across 
it.  These  precautions  were  absolutely  necessary  to  prevent 
disturbance  of  the  unstable  surface  soil,  and  to  give  the  plants 
a  chance  of  establishing  themselves. 

"  The  cost  of  the  cultural  operations  was  18s.  per  acre.  The 
wattled  fencing  was  constructed  by  a  local  battalion  of  Pioneers, 
and  therefore  involved  no  direct  outlay ;  had  the  work  been 
done  by  paid  labourers,  the  cost  would  have  been  about  2jr/. 
per  running  yard  of  fencing." 


638 


CHAPTER  IV. 

PROTECTION    AGAINST    FOREST    FIRES.* 

Forest  fires  are  nearly  always  caused  by  human  agency, 
generally  owing  to  carelessness,  but  are  sometimes  intentional  ; 
they  are  also  occasionally  due  to  lightning. 

It  is  intended  to  treat  the  subject  according  to  these  causes, 
taken  in  order. 

Se(7tion  I. — Forest  Fires  caused  by  Human  Agency. 
1.  Causes. 

The  following  acts,  omissions,  or  occupations  may  cause 
forest  fires : — 

Kindling  a  fire  without  permission  in  a  forest,  or  by  the 
side  of  a  forest  road,  in  order  to  warm  themSelves  or  to  cook 
their  food,  by  travellers,  or  men  engaged  in  felling  trees,  road- 
making,  etc. 

Leaving  a  fire,  which  has  been  lighted  by  permission  of  the 
forest  manager,  without  completely  extinguishing  it. 

Carelessness  of  charcoal-burners  whilst  burning  their  kihi, 
or  extracting  charcoal  from  it. 

Burning  branches  or  weeds  whilst  cultivating  crops  on 
forest-land  or  on  fields  adjoining  forests,  .also  burning  moor-, 
heather-,  or  grass-land. 

Burning  bark  to  destroy  beetles,  etc. 

Night-fires  by  poachers  after  fish  or  game  ;  burning  out 
wild  bees.  The  collection  of  wild  honey  and  wax  is  common  in 
East  Prussia  and  in  Piussia  and  India,  and  frequently  gives 
rise  to  forest  fires. 

Shooting  in  forests  with  rag  or  paper  wads. 

*  Gerding,  "  Fires  iu  the  Luneberger  Haide,"  "  Frstl.  Blttr.,".  1886,  p.  241  ; 
Fernandez,  "Notes on  Indian  Sylviculture"  (2nd  edition),  1893.  This  book  gives 
a  very  detailed  account  of  the  m«ii,siires  fur  couibating  forest  fires. 


CAUSES.  639 

Smoking  in  forests ;  throwing  down  burning  cigar-  ends  or 
matches. 

Carrying  on  dangerous  industries  in  or  near  forests,  such  as 
the  manufacture  of  pitch  or  turpentine,  and  also  iron-smelting 
furnaces,  or  foundries. 

Sparks  from  locomotive  engines,  especially  when  burning 
turf  or  lignite,  and  unprovided  with  spark-extinguishing 
apparatus. 

Intentional  tiring  of  forests  for  selfish  motives,  as  when 
shepherds  or  farmers  burn  extensive  forest  areas  to  obtain 
fresh  grass  for  their  flocks  and  herds,  for  it  grows  up  luxu- 
riantly after  a  forest  lire. 

Motives  of  revenge,  or  superstition,  as  in  India,  where  a 
deodar  forest  was  burned  to  propitiate  the  goddess  of  small-pox. 

It  follows  from  a  consideration  of  the  numerous  Ci^uses  of 
forest  fires  that  the  forester  must  be  wide  awake  to  prevent  such 
calamities.  Private  resources  are  here  quite  insufilicient,  and 
the  State  must  assist  by  framing  suitable  laws,  and  by  in- 
structing officials  to  be  active  in  enforcing  them. 

•     2.  Kinds  of  Forest  Fires. 

Forest  fires  may  be  in  the  ground,  in  the  soil-covering,  or  in 
the  crowns  or  stems  of  the  trees. 

a.  Ground-fires. 

These  occur  in  peat,  lignite,  or  coal ;  they  proceed  slowly 
unless  they  come  to  the  surface,  when  they  partake  of  the 
character  of  fires  in  the  soil-covering.  Ground-fires  rarely  occur 
in  forests. 

b.  Surface-fires. 

These  are  the  commonest  and*  most  important  fires  the 
forester  has  to  contend  against,  burning  the  dead  leaves, 
heather,  grass,  and  other  soil-covering  of  a  forest. 

c.  Fires  in  the  Croivns  of  Forest  Trees. 

These  are  less  frequent  in  Central  Europe,  thougb  common 
in  North  America  and  not  unfrequent  in  India.  They 
generally  arise  from  surface-fires,  which  spread  to  the  crowns 


640  PROTECTION    AGAINST    FOREST    FIRES. 

of  the  trees.    A  dense  coating  of  lichens  on  the  trees  increases 
the  danger  of  the  occurrence  of  crown-fires. 

(I.  Fires  in  Stems. 

Green  trees  seldom  catch  tire  even  from  lightning,*  and 
when  a  whole  stem  is  burned,  there  is  generally  some  decay 
present,  and  the  trunk  or  branches  of  the  tree  are  hollow. 

3.  Damage  dune, 
a.  General  Account. 

Forest  fires  do  direct  damage  by  destroying  whole  woods, 
and  especially  young  growth.  Reproduction  may  be  stopped 
for  the  year  by  the  destruction  of  blossom  or  fruit,  while, 
owing  4o  repeated  fires,  broadleaved  trees  which  are  not  killed 
become  misshapen  and  weakl3\  Game  may  be  killed  in 
extensive*  fires.  By  heath  fires  in  Hannover  many  hives  of 
bees  are  burned. 

Indirect  damage  consists  in  the  burning  of  the  dead  leaves 
or  needles  on  the  ground,  which  prevents  the  accumulation  of 
humus  and  the  improvement  of  the  soil,  and  renders  it  poor, 
hard  and  unsuitable  for  reproduction.  Henry  states  ("  Eev.  d. 
E.  etF.,"  June  1st,  1902)  that  high  forest  produces  the  following 
quantity  of  dead  leaves  in  6  years  per  acre : — 

Beech 10,500  lbs. 

Spruce 13,500  „ 

Scots  pine       ....     18,000  „ 
Coppice-with-standards   .         .       4,000  ,, 

There  is  about  If  lbs.  of  nitrogen  in  100  lbs.  of  dead  leaves, 
worth  about  Id.  a  pound.  The  value  of  the  nitrogen  destroyed 
in  the  dead  leaves  is  14s.  per  acre  for  coppice-with-standards, 
and  three  to  four  times  as' much  for  high  forest. 

A  proper  sequence  of  age-classes  may  be  interrupted.  The 
annual  burning  of  the  soil-covering  on  hill-sides  may  cause 

*  Von  Tubeuf,  in  1892,  observed  that  lightning  had  set  fire  to  a  growing 
spruce  tree,  and  the  fire  spread  to  neighbouring  trees. 

In  the  years  1877 — IS8H,  tliere  were  'M)  fires  in  the  Bavarian  State  forests, 
which  arose  as  follows:  l' from  ground-fires;  416  (82  percent.),  surface-fires; 
To  (40  per  cent.),  combined  surface  and  crown-fires  ;  15  (3  per  cent.),  combined 
surface  and  stem-fires  ;  G  (1  per  cent.),  stem-fires. 


DAMAGE    DONE.  641 

soil-denudation  when  it  is  followed  by  heavy  rain ;  this  was 
the  case  in  the  Siwalik  hill-range,  extending  over  fifty  miles 
between  the  rivers  Ganges  and  Jumna,  and  its  protection  from 
fire  was  demanded  in  1882  by  the  Indian  Irrigation  Department 
to  prevent  their  canals  from  silting  up.  Some  American  forests 
are  so  seriously  injured  by  fire,  that  rainwater  passes  over  the 
soil,  as  over  a  roof.  Observations  have  shown  that  up  to  90 
per  cent,  of  the  rainfall  runs  over  the  surface  of  burned  forests 
and  fills  the  watercourses  with  silt  and  other  debris. 

There  is  an  increased  tendency  to  breakage  and  to  damage 
by  insects,  also  to  growth  of  weeds  and  consequent  increased 
cost  of  sowing  and  planting.  Fires  are  extremely  injurious  in 
forests  on  shifting  sands. 

After  fires  in  Scots  pine  woods,  the  following  insects  may 
become  extremely  abundant  and  destructive :  Myciophilus 
inmpcrda,  L.,  in  England  and  German}^,  in  Germany  only, 
Pissodes  notatus,  Fabr.,  Tomicus  hidens,  Fabr.,  T.  Laricis, 
Fabr.,  HyUistes  palliatns,  Gyll.,  and  Hylurgus  minor,  Hrtg., 
Mi/elop]iilus  minor,  Hrtg.,  etc, 

b.  According  to  species. 

In  Central  Europe,  conifers  suffer  much  more  than  broad- 
leaved  species  from  fire,  owing  to  their  resinous  nature,  and  to 
the  inllammable  evergreen  needles,  which  favour  the  spread 
of  the  fires.  The  Scots  pine  and  the  Austrian  pine  are  the 
most  exposed  to  danger.  Other  pines,  such  as  Weymouth 
pine,  are  grown  only  to  a  limited  extent,  or,  as  in  the  case  of 
Cembran  and  Mountain  pine,  they  grow*  on  high  mountains, 
where  fires  are  less  dangerous.  The  greater  danger  the  Scots 
pine  experiences  from  fire  is  due  to  the  early  drying  up  of  its 
lower  branches  and  to  the  dry  nature  of  the  soil-covering, 
owing  to  the  imperfect  leaf-canopy  of  this  tree  and  to  the 
nature  of  the  localities  (heather  lands)  on  which  extensive  pine 
forests  occur.  In  France,  the  forests  of  maritine  and  Aleppo 
pines  are  specially  liable  to  fires. 

After  pines,  come  in  point  of  danger,  first,  the  spruce,  then 
silver-fir,  and  lastly,  larch,  owing  to  its  being  a  deciduous 
tree. 

F.P.  T   T 


642  PROTECTION    AGAINST    FOREST    FIRES. 

Pinus  rifiida,  Mill.,  in  the  Gotten  forest  near  Bonn,  in 
March,  1893,  produced  shoots  from  dormant  buds,  after  a  fire, 
but  not  a  complete  crop.  The  plants,  7-10  years  old,  were 
cut  back,  after  the  lire,  and  produced  9  or  10  shoots  each, 
38  cm.  high. 

Amongst  broadleaved  species,  rough-barked  trees,  such  as 
oak  and  elm,  withstand  fires  better  than  smooth-barked  trees, 
such  as  the  beech,  ash  or  sycamore. 

Fires  are  evidently  more  frequent  and  dangerous  in  High 
Forests  than  in  coppices. 

c.  Age  of  Trees. 

Young  woods  up  to  thirty  years  old  are  most  exposed  to  fire, 
at  first  owing  to  the  presence  of  weeds,  later  on,  as  the  struggle 
for  existence  is  strongest,  and  there  is  usually  most  dead  wood 
at  this  period. 

Well-stocked  woods  between  30 — 60  years  of  age  withstand 
fires  best  of  all,  as  middle-aged  coniferous  woods  after  the 
earlier  thinnings  contain  least  combustible  material,  such  as 
dead  wood,  grass  or  heather  undergrowth. 

Woods  over  60  years  of  age,  where  grasses  and  other  weeds 
spring  up,  again  become  more  endangered. 

The  following  average  figures,  taken  from  a  list  of  forest 
fires  in  Hanover  between  1864 — 84,  support  the  above  con- 
clusions. Out  of  1,000  acres  of  forest,  there  were  burned 
annually  during  these  twenty  years  : — 

Age.  Acres. 

Broadleaved  woods "170 

jl— 30yrs.    1*107 
Coniferous  woods         .         .         .    30—60         0-262 


Mixed  coniferous  and  broadleaved 
forest       


lover  60         0-354 
1      .         .       0-464 


(i.  Local  1/ 1/. 

Forests  in  plains,  on  account  of  the  greater  dryness  of  the 
air,  and  frequently  of  the  soil,  sufter  more  than  mountain- 
forests.  On  sunny  aspects  fires  spread  much  more  rapidly 
than  on  cool  northerly  slopes.     A  dry  sandy  soil  increases  the 


DAMAGE    DONE.  643 

danger.  Fire  burns  more  slowly  down-hill  than  up-hill,  and 
the  more  so  the  steeper  the  slope  and  the  stiller  the  air.  As 
a  slow  fire  is  more  easily  regulated  than  a  fast  one,  in  jhums, 
or  cultivations  on  forest  clearings  where  the  branches  and 
undergrowth  are  burned,  it  is  better  to  burn  down-hill. 

e.  Soil-C'oi'frin(j. 

A  tall  growth  of  heather,  genista,  broom,  or  grass,  etc., 
increases  the  danger  of  fire,  and  so  does  an  undergrowth  of 
juniper  or  of  sundry  conifers.  A  mossy  covering  is  pre- 
judicial only  in  seasons  of  drought,  and  a  covering  of  dead 
leaves  or  needles  is  usually  a  bad  combustible,  though  fire  in 
it  may  smoulder  on  for  days.  Whenever  much  branchwood, 
refuse  of  fellings  and  dead  fallen  wood,  lie  on  the  ground,  the 
danger  is  increased. 

Above  all,  Scots  pine  woods  on  heatliland  with  dry  soil 
and  soil-covering  and  combustible  foliage  are  most  exposed  to 
forest  fires.  In  a  pine  wood,  where  all  the  soil-covering  has 
been  removed,  a  fire  would  find  nothing  to  feed  on. 

In  badly  stocked  Indian  forests,  the  grass  is  frequently 
G — 8  feet  in  height,  and  in  the  open  in  Assam,  the  flowering 
stems  of  reeds  may  attain  a  height  of  24  feet.  The  fierceness 
with  which  a  fire  passes  through  tall  grass  during  the  dry 
season  must  be  seen  to  be  believed,  the  sparks  and  flames 
sometimes  crossing  rivers  one  hundred  yards  broad. 

The  leaves  of  many  of  the  Indian  forest  trees,  such  as  the 
teak  {Tectoria  (jrandis,  L.  fil.)  and  the  Sal  {Shorca  rohnsta, 
Gaertn.)  fall  in  March  and  April  during  the  dry  season  and 
when  dead  are  very  inflammable. 

/.  Densitij  of  (Jrowth  and  Ej- lent  of  Forest  Area. 

In  80  far  as  density  of  growth  kills  down  heather,  grass  and 
other  inflammable  undergrowth,  and  provided  all  dead  wood  is 
removed  in  the  thinnings,  a  densely  stocked  wood  is  less  liable 
to  be  ignited  than  a  thin  wood  with  inflammable  undergrowth. 
Once,  however,  that  a  dense  forest  is  ignited,  and  especially  if 
the  fire  is  in  the  crowns  of  the  trees,  it  can  generally  be  ex- 
tinguished only  by  a  fall  of  rain,  or  a  sufficiently  wide  gap  in 

T  T  2 


644-  PROTECTION    AGAINST    FOREST    FIRES. 

the  wood  caused  by  a  road,  river,  fields,  etc.,  or  by  purposely 
counter-firing  or  felling  trees  across  its  path. 

If  a  forest  is  liable  to  be  burned,  it  is  better  to  subdivide  it 
into  small  areas  by  fairly  numerous  rides  and  roads. 

//.  Season. 

Most  fires  in  Central  Europe  occur  in  dry  springs  from 
March  to  May  when  east  winds  prevail  and  the  dry  grass, 
leaves,  and  weeds  under  the  trees  and  the  presence  of  numerous 
workmen  in  the  woods  increase  the  danger. 

The  509  fires  in  the  Bavarian  State  forests  (p.  640),  during 
the  years  1877 — 83,  which  extended  over  1,160  acres,  occurred 
in  the  following  months:  January,  4  ;  February,  4;  March, 
118;  April,  114;  May,  140;  June,  51;  July,  43 ;  August,  20; 
September,  12 ;  October,  2 ;  November,  0 ;  December,  1. 
Thus  73  per  cent,  of  the  fires  occurred  in  March,  April  and 
May,  and  only  27  per  cent,  in  the  remaining  months.  Similar 
results  follow  from  statistics  in  Hesse. 

Forest-fires  also  occur  in  hot  and  windy  summers,  as  in  the 
years  1892  and  1893.  Winter  fires  may  occur  on  southerly 
aspects  with  dry  grass.  Two  hundred  and  fifty  acres  of  forest 
was  thus  burned  at  Oberammergau  on  the  14th  January,  1898, 
In  the  case  of  some  fires,  it  has  been  remarked  that  they 
generally  fall  off  in  violence  during  the  night,  but  recover 
force  again  after  sunrise,  this  being  due  to  the  daily  variation 
in  the  strength  of  the  wind,  and  sometimes  to  the  nightly  dew, 
which  may  extinguish  a  fire. 

In  tropical  and  semi-tropical  countries  forest-fires  occur 
during  the  dry  or  hot  seasons,  and  are  very  rare  during  the 
more  or  less  prolonged  summer  monsoon.  Thus  in  the  North- 
West  Himalayan  coniferous  forests,  there  may  be  fires  in 
November  and  December,  until  snow  has  fallen,  and  then 
again  from  April  till  the  monsoon  breaks  early  in  July,  after 
the  melting  of  the  snow. 

In  the  extensive  Sal  forests  at  the  foot  of  the  Himalaya 
mountains,  extending  from  the  Jumna  river  to  the  Borelli 
river  in  Assam,  there  is  danger  from  fire  from  February  till 
July,  and  this  danger  is  increased  by  the  fall  of  the  dead  Sal 
leaves  in  March  and  April.     In  the  western  part  of  these 


RECIISTER    OF   FIRES. 


645 


forests  the  clanger  from  fire  is  probably-  greatest  in  May  and 
June,  whilst  in  the  eastern  parts  in  Bengal  and  Assam, 
where  spring  rains  occur,  the  forests  are  fairly  safe  from 
fire  in  May,  owing  to  the  growth  of  fresh  grass,  which  is 
incombustible. 

4.  lieg'ister  of  Fires. 

Forest  fires  are  of  frequent  occurrence  in  the  heathlands 
of  Berkshire,  Surrey  and  Hampshire.  They  are  not  unfre- 
quent  in  Germany  in  spite  of  the  great  care  taken  to  prevent 
them,  but  their  extent  and  frequency  are  inconsiderable  when 
compared  with  Austria,  the  South  of  France,  Sweden,  Norway, 
Piussia,  Greece,  India  and  North  America.  In  this  last 
country,  forest  fires  frequently  extend  over  hundreds  of  square 
miles  of  forest,  and  Httle  or  no  trouble  is  taken  to  extinguish 
or  prevent  them.  The  most  disastrous  forest  fires  which 
have  occurred  in  Germany  during  the  present  century  are 
given  below  : — 

1800,  4th  to  21st  August,  5,675  acres  in  the  Black  Forest 
near  the  Katzenkopf  in  Wlirttemberg. 

18G3,  28th  to  30th  August,  3,300  acres  near  Kdnigsbruch  in 
W.  Prussia. 

1880,  1st  to  3rd  May,  3,250  acres  on  the  Lihieburg  heath. 

In  the  Prussian  State  forests,  during  the  interval  1892 — 
1898,  the  following  damage  by  fires  was  done  : — 


Yeur. 

High  Forest. 

Coppice 
and  C.  with 
standards. 

Wasteland 
Heather,  etc. 

Total. 

Area  stocked 

with  Scots 

Pine. 

acres. 

acres. 

acres. 

acres. 

1892-93 

8,436 

117 

i.<;23 

!(•  17(1 

6.285 

1893-94 

576 

14 

225 

SI  5 

410 

1894—95 

539 

— 

539 

427 

189.>— 96 

2,495 

— 

28 

2,523 

1,178 

1896—97 

102 

— 

4 

106 

IMI 

1897—98 

77 

— 

— 

77 

46 

It  may  be  stated  that,  in  Germany,  on  the  average,  out  of 
2,500  acres  of  forest  half  an  acre  is  burned  annually,  or  0'02  per 
cent,  of  the  forest  area. 

In  Austria,  in  1881 — 85,  there  were  1,717  fires  over  16,878 
acres,  the  amount  of  damage  done  being  i' 10,367. 


646  PROTECTION    AOAINST    FOREST    FIRES. 

In  Fi-cance,  between  1865  and  1870,  about  25,000  acres  of 
cluster-pine  forest  was  burned  in  Gascony,  and  a  large  area 
was  burned  in  1893,  including  1,200  acres  near  Arcachon  in 
the  forest  de  la  Teste.  There  was  also  a  large  conflagration 
in  these  forests  in  1898,  extending  over  63  miles,  and  causing 
damage  valued  at  i;80,000.  The  worst  districts  in  France, 
however,  for  forest  fires  are  the  Departements  of  the  Maures 
and  Esterel,  north  of  Marseilles,  where  large  areas  of  forest, 
chiefly  consisting  of  Quercus  Ilex,  L.  and  Pinus  Halepensis, 
Mill,  are  burned  every  year,  and  a  special  law  has  been 
enacted  for  their  protection  from  fire. 

Extensive  forest  fires  occur  every  year  in  Eussia.  In  Canada, 
in  1868,  it  was  estimated  that  400,000,000  dollars  worth  of 
standing  timber  was  destroyed  by  fire.  One  of  these  fires 
extended  160  miles  in  ten  hours. 

The  forest  fires  in  September,  1881,  and  again  in  1894  in 
the  States  Minnesota,  Wisconsin  and  Michigan  of  the  United 
States  of  North  America  were  of  enormous  extent,  hundreds 
of  human  beings  being  burned  with  their  houses  and  cattle. 
Statistics  are  wanting  to  give  some  idea  of  the  enormous 
annual  destruction  of  forests  in  N.  America  by  fire,  and 
especially  of  the  Southern  pine  {Pinus  jidlt'stris,  Mill.)  which 
yields  the  best  coniferous  timber  known  in  the  whole  world.* 

Protection  from  fire  of  the  State  forests  in  British  India  has 
been  seriously  undertaken  during  the  last  forty  years,  and 
measures  with  this  object  in  view  are  carried  out  on  a  large 
scale  and  at  considerable  cost  to  the  State.  Thus,  in  1899 — 
1904,  measures  were  taken  to  protect  from  fire  35,236  square 
miles  of  State  forest,  the  failures  in  this  area  amounting  to 
8  per  cent.  The  cost  of  protection  in  1891 — 92,  averaged  10 
rupees  a  square  mile,  or  at  Is.  2(1  per  rupee  11-9.  8^/.,  being  as 
low  as  2.9.  4d.  in  the  Bombay  Presidency.  Besides  the  above, 
there  are  66,196  square  miles  of  State  forest,  in  which  either 
the  forest  is  of  such  a  character  as  to  demand  no  special 
protective  measures  against  fire,  or  its  protection  has  not  yet 
been  undertaken.  This  takes  no  account  of  protection  against 
fire  in  the  forests  of  Native  States,  some  of  which  are 
admirably  managed. 

*  Of.  A  Primer  of  Forestry,  GifTord  Pinchot.     AVashington,  liio:?. 


protp:ctiye  measures.  647 

5.  Protective  ]\Ieasures. 

From  what  has  been  ah-eady  said,  it  is  clear  that  for  Central 
Europe,  protective  measures  against  fire  have  chiefl}^  to  be 
carried  out  in  coniferous  forests.  The  following  rules  will 
serve  for  private  forests  : — 

(a)  Mixture  of  broadlcaved  species  in  coniferous  forests, 
either  by  single  trees,  groups,  or  in  whole  compartments,  or  as 
protective  belts  round  the  coniferous  woods.  Such  protection 
is  specially  needed  along  the  borders  and  roads  through  Scots 
pine  forests. 

Birch,  oak,  beech,  black  poplar,  and  robinia  are  suitable 
species,  and  the  belts  should  be  25  to  35  feet  broad,  and  may 
be  either  High  Forest  or  Coppice.  Such  belts  are  largely  used 
in  the  Landes  of  Gascony  to  protect  the  cluster  pine  from  fire, 
and  should  be  kept  free  from  heather,  ferns,  dead  leaves,  and 
underwood,  which  are  readily  sold  for  litter.  In  the  Tucheler 
Heide,  ditches  2 — 3  metres  broad  are  dug  round  endangered 
woods,  and  the  spoil  heaps  formed  into  a  mound  inside  the 
ditch.  These  mounds  are  planted  with  birch  one  metre  apart, 
and  have  proved  efficient.  A  similar  plan  is  adopted  in  the 
sandy  parts  of  Windsor  forest. 

Except  in  coniferous  mountain  forests,  belts  of  broadleaved 
trees  are  practically  useless  in  most  parts  of  India,  as  trees 
that  retain  their  foliage  during  the  dangerous  months  will 
grow  well  only  in  moist  places.  In  Assam,  however,  belts  of 
evergreen  forest  growing  in  low  ground  on  either  side  of 
watercourses  frequently  act  as  protective  belts  to  the  drier 
deciduous  Sal  forest  on  either  side  of  them. 

b.  Fire-  Tn(rps. 

Wherever  forests  are  surrounded  by  inflammable  under- 
growth such  as  heather,  grass,  etc.,  fire-traces  of  sufficient 
breadth  should  be  made  along  their  boundaries,  and  internal 
fire-traces  are  also  required  for  all  extensive  inflammable  forest 
areas,  to  limit  the  extent  of  the  damage  done,  in  case  a  fire 
should  cross  the  boundary,  or  break  out  within  it.  The 
number  of  internal  fire-traces  required  for  a  forest  must  be 
left  to  local  experience,  but  the  forest  manager  should  remember 


648  PROTECTION    AGAINST    I'OREST    FIRES. 

that  a  considerable  area  of  forest  is  rendered  unproductive 
when  the  length  or  breadth  of  the  internal  tire-traces  are 
excessive,  and  that  the  cost  of  protection  is  thus  greatly 
enhanced,  so  that  he  will  limit  the  number  and  breadth  of  the 
fire-traces  to  the  minima  compatible  with  efficiency. 

Fire-traces  in  Europe  are  broadest  for  coniferous  forest,  but 
rarely  exceed  100  feet  in  breadth,  while  in  India  they  are 
sometimes  400  feet  broad. 

^Yhenever  the  soil-covering  on  the  traces  can  be  utilised  for 
thatching  material,  litter  or  fodder,  it  should  be  cut  and  removed. 
This  may  often  be  done  by  concessioners  at  no  cost  to  the  owner 
of  the  forest,  or  even  on  payment  to  him  of  a  certain  sum.  It 
frequently  happens,  however,  that  the  soil-covering  has  no 
local  value,  and  must  then  be  carefully  burned  to  avoid  the 
greater  expense  of  cutting  it. 

Before  burning  fire-traces,  the  soil-covering  is  usually  cut 
on  guide-lines  on  either  side  of  the  trace,  their  breadth  being 
about  three  feet  more  than  the  height  of  the  covering.  For 
greater  safety,  cross  lines  as  broad  as  the  guide-line  are  some- 
times cut  at  intervals  across  the  trace  itself,  so  as  to  divide  it 
into  segments,  each  of  which  may  be  burned  separately. 

The  guide-lines  should  be  cut  some  time  before  the  fire-trace 
is  to  be  burned,  and  the  cut  material  thrown  on  the  trace, 
where  it  will  dry,  and  facilitate  the  burning.  A  broad  short 
scythe  or  a  sickle  may  be  used  to  cut  the  grass,  heather,  etc., 
from  the  guide-lines. 

In  burning  the  traces,  it  is  a  golden  rule  to  remember  that 
grass  and  heather  in  the  open  become  dry  sooner  than  under 
cover  of  the  forest,  so  that  border  fire-traces  may  be  burned 
before  the  internal  ones.  In  firing  a  trace,  a  still  afternoon 
should  be  chosen  and  men  placed  on  either  side  of  it,  two  of 
whom  fire  the  edges  of  the  traces  up  to  a  cross  line,  if  one  haa 
been  cleared,  or  if  not,  to  a  sufiicient  distance  for  the  other 
men  to  be  able  to  beat  out  the  return  fire  which  runs  along 
the  ground  in  the  stubble  towards  the  forest.  The  other  men, 
armed  with  evergreen  boughs,  which  they  can  use  to  protect 
their  faces  from  the  heat  of  the  fire,  keep  back  on  the  guide- 
lines, or  even  in  the  forest  beyond  them,  until  they  see  the 
return  fire  approaching  too  near  the  edge  of  the  forest,  when 


PROTECTIVE    MEASURES.  649 

they  rush  forward  and  beat  it  out,  leaving  the  flames  from 
either  side  to  meet  in  the  trace,  and  burn  all  the  standing 
grass  or  heather  within  it. 

It  should  be  noted  that  however  still  the  air  may  be,  before 
firing  a  trace  has  commenced,  the  ascent  of  hot  air  due  to  the 
fire  will  draw  in  colder  air  from  all  sides  to  fill  up  the  vacuum 
thus  produced,  and  if  the  wind  be  blowing  in  the  faces  of  the 
men  on  one  side  of  a  fire-trace,  lighting  in  the  middle  of  the 
trace,  as  well  as  along  its  sides,  will  draw  in  the  flame  away 
from  the  men  on  the  dangerous  side,  in  spite  of  the  wind,  and 
will  thus  greatly  facilitate  their  work. 

On  hill-sides,  fire-traces  should  run  along  ridges,  and  they 
may  be  made  zigzag  when  the  hill-sides  are  steep,  and  are 
burned  downhill.  In  forests  where  numerous  fire-traces  are 
cleared  annually,  it  is  often  advisable  to  mark  off  the  limits  of 
the  guide-lines  by  a  simple  trench  of  the  breadth  and  depth 
of  a  plantation-hoe. 

AYhere  the  soil-covering  is  very  dense  and  tall,  it  is  better 
to  burn  the  traces  twice,  at  first  before  they  are  completely 
dry,  and  again  whenever  dead  leaves  fall  on  the  traces  after 
the  grass  has  been  burned  ;  dead  leaves  should  be  swept  away 
or  burned,  in  order  to  render  the  trace  impassable  by  fire. 
This  leaf-burning  is,  however,  a  simple  operation  which  may 
be  carried  out  by  three  or  four  men,  whilst  the  first  burning 
in  dense  tall  grass  may  require  20  men,  or  more. 

If  by  accident,  during  the  burning  of  a  fire-trace,  the  fire 
sliould  get  into  the  forest  on  either  side  of  it,  the  further 
burning  of  the  trace  must  be  suspended  until  the  fire  in  the 
forest  has  been  extinguished ;  to  do  this  it  must  be  attacked 
on  both  sides  by  the  gang  of  men  and  driven  into  the  shape  of 
a  wedge. 
.  One  or  two  trustworthy  men  should  follow  the  firing  gang 
on  either  side  of  the  trace,  and  should  carefully  extinguish  all 
smouldering  embers  on  the  guide-lines,  and  throw  all  burning 
twigs  and  pieces  of  wood  from  the  latter  on  to  the  middle  of 
the  trace,  so  that  there  may  l)e  no  possibility  of  the  forest 
catching  fire  from  the  very  means  which  are  taken  to  protect  it. 

Very  full  details  as  regards  the  practice  of  burning  fire- 
traces  are  given  in  Fernandez'  Indian  Sylviculture,  and  need 


G50 


PROTECTION   AGAINST    FOREST    FIRES. 


not  be  repeated  here,  as  in  Europe  the  work  of  burning  fire- 
h'nes  is  much  simpler  than  in  hot  countries. 

r.  Wati]tii}(j  the  Foreafs. 

During  the  dry  season,  after  all  the  fire-traces  have  been 

cleared,    and    until 

sufficient  rain  has 
fallen  to  render  the 
forest  safe  from  fire, 
it  is  often  necessary 
to  appoint  special 
patrols  to  watch  the 
forest,  in  addition  to 
the  ordinary  protec- 
tive establishment. 
These  men  warn  all 
])assengers  along 
the  roads  of  the 
danger  from  fire, 
sweep  ofi"  or  burn 
dead  leaves  on  the 
fire-traces,  relieve 
one  another  in 
night  -  watching, 
and  instantly  report 
all  cases  of  fire  to 
the  forester  and 
forest  guards,  when 
organised  measures 
can  be  taken  to  ex- 
tinguish it.  In 
some  cases,  seats 
are  made  for  the 
lire  -  watchers  in 
trees,  with  ladders 
for  ascending  them, 
in  order  that  any 
In  Russia,  special 


Russian  watch  tower  for  fire-guard. 


outbreak  of  fire  may  at  once  be  detected, 
watch-towers  are  erected  (Fig.  289). 


PROTECTIVE    MEASURES.  051 

(1.    Trenrliea  round  Peat  Deposits^. 

Wherever  peat  occurs  in  the  forest  soil,  deep  trenches  should 
be  dug  round  the  peat  deposits  to  isolate  them  from  possible 
forest  fires. 

p.   Coiuluct  of  Tliiiiiiinfif<. 

Early  and  careful  thinnings  should  be  made  in  3'oung 
coniferous  woods,  and  all  dead  branches  should  be  pruned  off 
and  removed.  The  least  that  should  be  done  is  to  clear  the 
boundaries  of  all  compartments  of  dead  -wood  to  a  breadth  of 
30  to  45  feet. 

/.  Ahinj   Bail W((y- Lines. 

Fire-traces  must  be  kept  clear  of  woody  growth,  and  of  dead 
leaves,  heather,  and  other  inflammable  material  along  all 
railway  lines  passing  through  forests.  Most  forest  fires  due 
to  sparks  from  locomotives  break  out  within  30  feet  of  a  railway 
line,  but  to  render  the  fire-traces  quite  effective,  they  should 
be  60  feet  broad.  The  French  law  regarding  forest-fires  in 
the  Maures  and  Esterel,  makes  such  fire-traces  compulsory 
along  all  railway-lines  running  through  the  forests  of  those 
Departements. 

A  short  act,  for  the  United  Kingdom,  named  the  Eailway 
Fires  Act,  became  law  on  the  4th  August,  1905,  making  railway 
companies  liable  for  damage  done  to  crops,  to  the  extent  of 
;£100.  This  limit  to  the  value  of  the  damage  does  not  meet 
the  necessities  of  the  case,  as  regards  extensive  woods  on  dry 
sandy  soil. 

//.  Roadfi  find  Bi'dcft  in   the  Forest. 

The  network  of  forest-roads  and  rides  may  afford  consider- 
able assistance  against  fires.  In  order  to  protect  the  forest  on 
either  side  of  roads  from  any  risk  of  fire  from  sparks  from 
pipes,  etc.,  of  travellers,  or  cartmen,  all  inflammable  under- 
growth and  dead  leaves  should  be  cleared  from  the  roads,  and 
from  a  strip  10  to  15  feet  broad  on  either  side  of  them. 

Some  of  the  rides  may  be  cleared  as  fire- traces,  and  where 
the  prevalent  winds  are  from  the  west,  it  is  better  that  rides 
to  be  cleared  as  fire-traces  should  be  at  an  angle  of  about  75 


652  PROTECTIQN    AGAINST    FOREST    FIRES. 

degrees  to  the  wind  direction,  as  it  is  easier  to  burn  them,  and 
they  afford  a  broader  barrier  to  a  fire  coming  from  the  west 
than  if  they  were  simply  at  right  angles  to  the  direction  of 
the  wind. 

Besides  roads  and  rides,  watercourses  often  form  effective 
fire-traces  when  the  undergrowth  is  cleared  away  and  burned 
on  only  one  side  of  the  watercourse  at  a  time,  but  crossing 
the  watercourse  at  its  bends,  so  as  to  form  a  uniformly  broad 
trace. 

h.  Size  of  Workinff  Sections. 

Where  forest  fires  are  to  be  feared,  the  working-sections 
should  be  comparatively  small,  so  that  there  may  not  be 
extensive  tracts  of  young  woods,  in  which  the  danger  from  fire 
is  greatest  over  large  areas. 

/.   Clearance  of  Felling-Areas. 

The  felling-areas  should  be  rapidly  cleared  of  all  refuse,  and 
the  produce  of  the  thinnings  also  removed  quickly,  especially 
in  the  case  of  faggots  from  coniferous  trees. 

When  workmen  sleep  on  the  feUing-areas,  great  care  must 
be  taken  as  regards  smoking,  and  fires  should  be  allowed  only 
inside  their  huts,  which  should  be  surrounded  by  broad  fire- 
traces,  as  the  wind  might  otherwise  blow  sparks  into  the  forest. 
In  parts  of  Northern  India,  during  the  hot  dry  months  of  May 
and  June,  it  has  l)een  customary  to  suspend  all  timber  works 
owing  to  the  risk  of  fire  from  the  woodmen  and  carters,  but 
these  men  can  easily  be  taught  to  guard  the  forest  from  fire, 
and  it  is  doubtful  whether  this  restriction  is  necessary. 

j.  Other  M east/ res  of  Protection. 
Regulations  restricting  fires  and  smoking  in  forests  in  dry 
seasons,  and  also  regarding  the  use  of  fire-arms,  should  be 
made  by  the  State.  The  most  complete  State-regulations 
regarding  forest  fires  are  those  enacted  in  1893  by  the  French 
Legislature.  Somewhat  similar  rules  are  enforced  in  British 
India,  except  as  regards  railways,  but  they  apply  only  to  certain 
State  forests.  The  private  forest-manager  must  see  that  all 
State  regulations  regarding  forest  fires  are  observed,  and  should 


PROTECTIVE    MEASURES.  653 

instruct  the  workmen  engaged  in  occupations  endangering  the 
forest,  such  as  charcoal  or  hme  hurning,  what  protective 
measures  they  must  adopt,  and  should  see  that  his  instructions 
are  followed. 

In  the  British  Isles,  in  addition  to  the  law  regarding  fires 
caused  hy  locomotives  already  referred  to  (p.  651),  there  is 
a  Scotch  law  (13  Geo.  III.,  cap.  54),  making  it  illegal  to 
burn  muir  or  heath  land  in  Scotland  from  lltli  April  till  1st 
of  November,  under  penalties  of  -iOs.,  .i*5,  and  4*10  for  first, 
second  and  third  offences,  with  alternative  of  imprisonment 
for  six  weeks,  two  or  three  months  respectively. 

During  the  dangerous  season,  the  forest  guards  must  be 
constantly  on  the  watch  against  fires,  as  well  as  the  fire-patrols, 
if  it  has  been  found  necessary  to  engage  additional  men. 
All  contraventions  of  the  State  regulations  regarding  forest 
fires  should  be  at  once  reported  to  the  police,  or  to  a 
magistrate. 

In  order  to  prevent  intentional  tiring  of  a  forest,  no  privileges 
to  cut  grass,  or  to  graze,  should  be  conceded  on  an  area  which 
has  been  burned. 

In  India  difficulties  arise  with  sportsmen,  when  from  fear 
of  fires  the  forests  are  closed  to  shooting  during  a  season  which 
would  be  otherwise  open.  Special  permission  is  sometimes 
given  by  Government  to  forest  officers  to  open  the  forest 
temporarily  to  shooting  after  a  heavy  shower  of  rain,  during  the 
dry  season,  or  in  order  to  shoot  tigers,  or  other  destructive 
beasts.  The  shelter  afforded  to  game  or  noxious  animals  by 
high  grass  near  villages  may  become  a  great  nuisance  to  the 
villagers,  and  the  forest  officers  should  not  carry  the  practice 
of  protection  from  fire  too  far  in  such  cases,  and  it  may  even 
be  advisable  to  burn  off  worthless  tracts  of  scrub  forest  or 
grassland  for  pasturage,  so  as  to  keep  public  opinion  on  the  side 
of  the  forester.  On  the  other  hand,  Indian  State  forest  officers 
have  direct  power  to  arrest  offenders,  and  to  call  on  all  forest 
right-holders  and  workmen  to  assist  in  extinguishing  a  fire, 
and  in  certain  cases,  privileges  and  rights  to  forest  produce 
may  be  temporarily  suspended  by  the  Government,  in  cases  of 
wilful  firing  of  a  forest  by  villagers,  or  their  refusing  assistance 
when  once  a  fire  has  broken  out. 


654.  PROTECTION    AGAINST    FOREST    FIRES. 

A  system  of  telephones  in  endangered  forests  is  extremely 
useful,  enabling  the  managers  to  mass  men  at  points  where  a 
fire  has  broken  out.  In  the  Count  of  Frankenberg's  forests, 
at  Tillowitz  in  Silesia,  such  a  system  exists,  connecting  the 
forest  guards  with  the  manager's  office. 

6.  Rules  for  Extiiiijuishing  Forest  Fires, 
a.  General  Rules 

If  a  fire  should  break  out  in  a  forest,  the  manager  must  call 
on  all  available  labourers  from  the  nearest  villages,  as  well  as 
the  forest  workmen,  to  hurry  to  the  site  of  the  tire,  and  carry 
out  the  necessary  measures  for  extinguishing  it.  The  workmen 
should  bring  bill-hooks,  hoes,  iron-rakes,  and  axes,  and  provide 
themselves  with  saplings  or  branches  to  beat  out  the  fire.  The 
chief  object  should  be  to  limit  the  progress  of  the  fire  at  the 
smallest  possible  sacrifice  of  still  unburnt  woods.  This  is  best 
done  by  attacking  the  fire  on  both  sides  nearly  parallel  to  the 
direction  of  the  wind,  and  gradually  beating  it  out  in  the  shape 
of  a  wedge.  The  burned  area  must  be  abandoned  to  the  fiames. 
The  result  depends  on  the  presence  of  mind,  courage,  energy, 
decision  of  character  and  practical  directions  of  the  head 
forester  present,  and  on  the  obedience,  zeal  and  skill  of  the  men. 
The  chief  forester  present  must  be  thoroughly  acquainted  with 
the  locality,  as  it  may  be  necessary  to  sacrifice  an  area  of 
unburned  forest  by  counterfiring.  In  order  to  detect  at  once 
any  fires  arising  from  sparks  which  may  cross  fire-traces,  men 
must  be  posted  at  all  threatened  points  around  the  actual  fire. 
As  it  may  take  several  days  to  extinguish  an  extensive  forest 
fire,  arrangements  may  be  required  to  work  the  available  labour 
force  by  relays,  and  to  supply  the  men  at  work  with  food  and 
drink. 

In  countries  like  India,  where  forest  fires  are  common, 
wherever  the  villagers  willingly  come  forward  to  help  in  extin- 
guishing fires,  concessions  may  be  made  to  them  of  dead 
firewood  or  thatching  grass,  and  in  case  of  the  fire  burning 
the  houses  of  a  village,  situated  near  the  forest,  the  manager 
should  be  ready  to  help  with  building  and  thatching  material, 
either  free  or  at  cheap  rates. 


PROTECTIVE    MEASURES.  655 

In  such  localities  more  than  half  the  battle  against  forest 
fires  is  won,  when  the  protection  of  the  forest  from  fire  meets 
with  sympathy  from  the  neighbouring  villagers. 

In  France  and  Germany,  it  is  usual  to  call  out  the  soldiers 
of  a  regiment  quartered  near  the  forest  to  assist  in  extinguish- 
ing extensive  forest  fires. 

The  cost  of  extinguishing  fires  varies  between  20  and  50  per 
cent,  of  the  damage  done  ;  in  Saxony,  1889-93,  it  was  23  per 
cent. 

b.  Ground  Fires. 

The  burning  area  must  be  isolated  by  digging  trenches, 
which  must  be  deep  enough  to  prevent  the  fire  from  finding 
its  way  below  them.  Water  should  be  poured  on  the  burning 
turf,  or  soil  from  the  trenches  heaped  on  to  it. 

c.  Surface  Fires. 

The  fire  should  be  beaten  out  with  green  branches  as 
already  explained.     Wherever  there  is  a  dense  undergrowth. 


29(1.— Kake  used  iu  protection  against  fire. 


as  in  the  case  of  heather,  it  is  better  to  beat  down  the  fire 
vertically,  but  where  the  soil-covering  is  low,  the  branches 
should  be  used  backwards  and  forwards  like  brooms  to  sweep 
it  out. 

At  the  spot  where  the  fire  commenced,  workmen  should 
clear  away  a  strip  of  the  soil-covering  in  order  to  isolate  the 
fire.  Iron  rakes.  Fig.  290,  of  a  special  kind  can  be  used  for 
this  purpose  with  advantage,  and  unburned  litter  may  thus  be 
drawn  by  the  teeth  of  the  rakes  towards  the  workmen,  or 
burning  litter  be  pushed  away  by  using  the  rake  reversed. 

Freshly  dug  up  earth  may  be  thrown  on  the  fire. 

A  clearance,  or  fire-trace,  may  be  made  in  front  of  the  fire 
to  stop  its  further  progress.     The  distance  of  this  from  the 


656  PROTECTION    AGAINST    FOREST    FIRES. 

lire  should  be  so  chosen  that  the  fire-trace  may  be  completed 
before  the  fire  reaches  it.  In  making  this  fire-trace,  all  the 
soil-covering  should  be  cut  and  removed,  and  if  there  is  time, 
a  trench  may  be  dug,  and  the  earth  from  it  piled  up  towards 
the  fire. 

It  may  be  necessary  to  counterfire  from  a  road,  stream, 
ride  or  fire-trace  ;  the  soil-covering  is  then  burned,  and  this 
fire  directed  so  as  to  meet  the  advancing  forest  fire,  when  the 
two  fires  meet  and  become  extinguished  for  want  of  fuel. 
This  is  a  very  efficacious  remedy,  but  demands  great  care, 
and  can  be  carried  out  only  when  the  air  is  fairly  still,  and 
the  undergrowth  not  too  high,  or  fire  may  ignite  the  crowns 
of  the  trees ;  it  will  evidently  be  resorted  to  only  in  extreme 
cases. 

(I.  Crown  Fires. 

The  wooded  area  must  be  interrupted  by  felling  a  strip  of 
trees  in  front  of  the  fire,  which  is  best  done  along  a  road  or 
ride.  The  smaller  trees  should  be  dragged  away,  if  there  is 
time  to  do  so,  taller  trees  should  be  felled  towards  the  fire  and 
their  crowns  lopped  off,  if  possible. 

Counterfiring  is  of  little  use  against  crown-fires,  but  may  be 
tried,  if  only  young  growth  is  burning. 

c.  Sle)7is  OH  Fire. 

When  a  solitary  hollow  tree  is  burning,  the  hole  may  be 
stopped  with  sods  or  earth.  If,  however,  the  hollow  extends 
to  the  top  of  the  tree  or  through  one  of  its  main  branches,  the 
tree  must  be  felled,  after  clearing  away  the  undergrowth  and 
soil-covering  all  round  it,  and  the  fire  should  then  be  extin- 
guished with  water  or  soil. 

7.   Watchiiif/  the  Site  of  the  Fire. 

In  order  to  guard  against  a  fresh  outbreak  of  a  forest  fire, 
its  site  should  be  carefully  watched  by  trustworthy  persons 
until  all  further  danger  is  over.  In  a  coniferous  forest, 
where  the  soil  is  deeply  covered  with  dead  needles,  danger  of 
rekindling  may  be  incurred  for  a  week  or  more  after  the  fire 
has   been   extinguished,    unless    rain    falls.      The    manager 


TREATMENT    OF    INJURED    WOODS.  657 

should  go  completely  round  the  burned  area  and  see  that  it  is 
properly  isolated  from  the  surrounding  forest  by  clearings  of 
the  soil-covering  and  trenches.  All  burning  pieces  of  fallen 
wood  on  the  site  of  the  fire  should  be  covered  with  earth,  and 
wherever  any  fire  reappears,  it  should  be  at  once  beaten  out. 

8.   Treatment  of  Woods  Injured  by  Fire. 

The  treatment  of  burned  woods  depends  on  their  age,  the 
extent  of  the  fire  and  the  amount  of  injury  done  to  the  trees. 

Burned  younf/  coniferous  woods  should  almost  always  be  dug 
up  and  the  area  at  once  restocked.  Occasionally  young  Scots 
pines  may  put  out  fresh  needles  and  recover. 

Older  coniferous  woods  with  uninjured  crowns  and  with 
merely  their  bark  singed  may  be  left  standing.  If,  however, 
the  bast  and  sapwood  should  be  seriously  affected,  it  will  be 
necessary  to  fell  the  trees,  and  especially  if  it  is  subsequently 
found  that  they  have  been  attacked  by  beetles,  as,  for  instance, 
Myclopldlns  inniperda,  L.,  which  will  breed  in  the  summer  in 
pine  woods  that  have  been  l)urned  in  the  spring,  and  j)ro- 
ceed  in  the  autumn  to  thin  out  the  crowns  of  all  the  trees 
around  the  site  of  the  fire.  Where  this  is  to  be  feared,  it  is 
better  to  fell  all  trees  that  are  apparently  so  weakened  by  the 
fire  as  to  encourage  the  breeding  of  these  destructive  insects. 

We  should  not,  however,  be  very  ready  to  fell  broadleaved 
trees,  as  oak-woods,  for  instance,  sometimes  recover  after 
being  burned,  especially  the  dominating  trees,  but  beech  are 
more  susceptible  to  damage  by  fire.  It  is  better  in  doubtful 
cases  to  await  the  next  season  of  vegetation  before  deciding 
what  is  to  be  done.  Young  broadleaved  woods  may  be  cut 
back  if  seriously  injured,  but  even  this  operation  may  be  put 
oft'  till  the  ensuing  spring,  as  it  may  then  prove  unnecessary. 

More  information  is  necessary  as  to  whether  it  is  advisable, 
in  particular  cases,  to  fell,  cut  back  or  leave  trees  that  have 
been  injured  by  fire. 

9.  Insurance  against  Forest  Fires. 

After   several   fruitless   attempts   to   found   a    society   for 
assuring  forests  against  fire,  in  1895  the  Munich  Gladbacher 
F.P.  U   u 


658  PROTECTION    AUAINST    LIGHTNING. 

Fire  Insurance  Company  agreed  to  insure  against  damage  by 
forest  fires  throughout  Germany,  and  appointed  a  forest 
expert  as  manager  of  this  branch  of  their  business. 

The  company  insures  standing  crops  of  trees  up  to  the  age 
of  60  years,  and  felled  timber  as  long  as  it  is  the  property  of 
the  insurer.  Damage  in  burned  forests  is  assured  at  its  cost- 
value  whenever  this  exceeds  its  actual  value.  The  premia 
vary  according  to  the  greater  or  less  danger  of  particular 
crops  from  45  pfennigs  to  4  marks  per  1,000  marks  of  their 
insured  value.     For  ordinary  crops  1 — GO  years  old — 

Pure  broadleaved  woods  .         .     085  marks. 

Mixed  coniferous        ,,      .         .     1*20       „ 

Pure  coniferous  ,,      .         .     2*00       ,, 

In  Switzerland,  insurance  against  fire  has  been  effected 
(1906)  at  10  per  cent,  of  the  endangered  capital. 

In  Belgium,  insurance  can  be  effected  against  forest  fires  at 
the  following  rates  of  premium  per  1,000  francs  value  : — 

Broadleaved  woods  .         .     60  centimes. 

Conifers  under  20  years  old     .     6  francs. 
„       over        ,,         „         .5  francs. 


Section  II. — Effects  of  Lightning  on  Trees.* 

Much  has  recently  been  written  about  lightning  and  its 
effects  on  trees,  but  the  causes  of  thunder-storms  are  not  yet 
clearly  known.  The  action  of  lightning  on  trees  also  requires 
further  study. 

1.  Mode  of  Striking. 

"When  lightning  strikes  a  terrestrial  object  it  is  termed  a 
"  direct  stroke.'" 

It  is  termed  liot  when  it  sets  fire  to  the  object,  it  is  otherwise 
cold. 

A  hack-stroke  occurs  when  the  accumulated  positive  or 
negative  electricity  at  the  top  of  an  object,  such  as  a  tree, 

*  Klein,  "  Das  Gcwitter  und  die  dasselbe  begleitenden  Erscheinungeii."  Graz, 
1871. 

Baur,  "  Dcr  Blitz  als  Waldveiderber,"  "Monatschrift  fiir  das  Forst.  u. 
Jagdwesen,"  1873,  p.  97, 

Rippold.  "  Die  Eustehung  tier  Gewittcr."     Frankfurt-a.-M.,  181)7. 


MODE   OF   STRIKING. 


659 


strikes   downwards,    the    inducing    electricity    in   the   cloud 

having  struck  in  another  direction,  another  tree  for  instance. 

One  theory  of  the  action  of  lightning,  that  of  F.  Cohn,  of 


Fig.  2'Jl.— Elm  treu  .-truck,  by 


Breslau,  is  that  when  lightning  strikes  a  tree  the  wet  cambium- 
zone   conducts    the   electrical   discharge,  and   the   contained 

U  U  2 


660 


PrtOTFXTION    AOAINST    LIGHTNING. 


water  is  suddenly  converted  into  vapour.  The  expansion  thus 
caused  strips  off  the  bark  at  the  points  of  least  resistance, 
and  if  the  bark  be  smooth  and  thin,  large  pieces  of  it  may  be 
removed  (Fig.  291).  The  wood  may  also  be  split  from  the  top 
of  the  tree  downwards,  the  lightning  entering  at  the  fine  twigs 
on  the  top  of  the  tree  and  running  down  the  stem  straight  or 
spirally  according  to  the  direction  of  the  fibres. 

2.  Damage  done, 
a.   Cimeral  Arroiint. 
The  effects  of  lightning  on  a  tree  are  very  various  ;  if  the 
tree  be  split,  the  bark  is  usually  removed  only  in  a  narrow 


Fig.  292. — Horizontal  lightning-stroke  along  «  Z*  c  on  a  beech  tree. 
a  Four  meters  above  tlie  ground.      h  d  A  short  dark  line. 

strip  on  either  side  of  the  tree,  otherwise,  occasionally  in  large 
flakes.  Even  in  the  former  case  the  tree  generally  dies,  it 
may  be  after  a  few  years. 

In  other  cases,  pieces  of  wood  are  split  off  the  stem,  of  all 
sizes  up  to  several  yards  in  length  (Fig.  293).  The  lightning 
has  even  been  known  to  enter  a  beech  tree  100  years  old,  in 
Hesse,  on  the  11th  July,  1886,  horizontally  and  then  strike 
down  through  its  axis,  as  shown  in  Fig.  292.  Sometimes  large 
arms  of  a  tree,  or  its  whole  crown,  have  been  broken  off  by 
lightning.     As  a  rule,  the  lightning  runs  down  the  tree  into 


DAMAGE    DONE.  661 

the  ground,  but  in  3  per  cent,  of  the  cases  observed  it  i^assed 
off  to  other  trees  before  doing  so. 

Neither  carbonisation  nor  tearing  open  of  cells  have  been 
observed  on  trees  struck  by  lightning. 

The  injured  parts  observed  on  the  stem  or  main  branches 
of  a  tree  are  never  the  first  point  attacked.  The  hghtning 
almost  always  strikes  the  fine  topmost  twigs  (the  best  con- 
ductors), and  proceeds  thence  along  the  main  boughs  and 
stem.  It  then  generally  follows  the  direction  of  the  fibres, 
the  path  of  least  resistance.  If  the  fibres  are  twisted,  it 
follows  a  spiral  path.  The  cambium,  wood,  and  pith  of  a 
tree  struck  by  lightning  become  discoloured,  and  often  the 
topmost  leaves  turn  brown,  those  below  remaining  green. 

Very  little  is  known  regarding  the  effect  of  lightning  on  the 
inner  stnicture  and  technical  qnalitij  of  timber.  It  is  assumed 
that  wood  struck  by  lightning  has  its  hardness  and  strength 
reduced.  Wood  and  bark-beetles,  wood-wasps  and  fungi, 
attack  the  tree,  which  soon  dies.  It  should  therefore  be  felled 
and  converted  as  soon  as  possible. 

"When  an  unsound  tree  is  struck  by  lightning  it  is  some- 
times set  on  fire,  and  the  fire  may  then  spread  to  the 
surrounding  forest. 

It  has  also  been  repeatedly  observed  in  coniferous  forests, 
that  sometimes  a  whole  group  of  trees  may  die  from  the 
efiects  of  lightning,  the  marks  of  which  may  only  be  visible 
on  one  of  the  trees.  This  takes  place  some  time  after  the 
occurrence,  and  leaves  an  ugly  gap  in  a  fine  wood.  This  has 
been  hitherto  observed  only  in  crops  of  Scots  pine,  spruce, 
silver-fir  and  larch.  It  may  be  the  effect  of  backstroke 
(p.  658).  In  such  cases  the  dead  trees  should  be  carefully 
examined,  as  bark-beetles  have  been  afterwards  proved  to  have 
caused  the  death  of  the  unstruck  trees  in  certain  cases. 

The  soil  may  be  the  cause  (p.  GOi),  or  small  lightning 
strokes  accompanying  the  principal  stroke.  Such  a  stroke  is 
termed  [iroup-strokc. 

h.  Accordimj  to  Species. 

All  species  of  trees  are  liable  to  be  struck  by  lightning,  but 
oaks  and  other  species  with  deep  roots  appear  to  be  most 


662 


PROTECTION   AOAINST   LIGHTNING. 


exposed  to  this  danger,  perhaps  on  account  of  their  roots 
forming  better  conductors  to  the  moist  subsoil  than  those  of 
shallow-rooted  species. 

According  to  the  valuable  observations  made  annually  by 
Dr.  Hess  from  1874  to  1890  in  the  forests  of  Lippe-Detmold,* 
among  broadleaved  trees  the  oak  suffers  most,  among  conifers 
the  Scots  pine.  Then  follow  spruce  and  beech.  The  birch, 
poplars,  ash,  alder,  willows,  larch,  and  other  trees  suffer  only 
exceptionally. 

Trees  Struck  in  Lippe-Detmold,  1874 — 1890. 


Broadleaved  trees. 

Conifers. 

Oaks 

310 

Scots  pine  . 

.     108 

Beech 

33 

Spruce 

.       39 

Birch 

10 

Larch 

.       11 

Poplars 

6 

Austrian  pine      . 

1 

Ash    . 

4 

Weymouth  pine  . 

1 

Willows 

2 

Others 

5 

Other  trees 

8 

Total 

373 

Total 

.     165 

The  forest 

was  stocked 
Oak 
Beech 
Spruce 

as  fol 

lows : — 
11  per  cent. 
70    „      „ 
13    „      . 

Scots  pine      . 

•  6    „       „ 

100 


The  danger  therefore,  considering  the  beech  as  1,  was  6  for 
a  spruce,  37  for  a  Scots  pine,  and  GO  for  an  oak. 

Other  observations  by  Collodon,!  Hellmann,^  Cohn,  and 
Caspary  give  Eomewhat  different  results. 


•  '-Ztschrft.  fi-.  Frst.  ii.  Jgdw.,"  1S79— 1( 
t  "  AUg.  Frst.  u.  Jgdztjr.,"  1S75,  p.  Uo. 
I  -Frstl.  Blttrn.,'  ISH'J,  p.  2G. 


DAMAGE    DONE. 


663 


Thus  Hellmann,  considering  danger  for   the   beech   from 


lightning  as  1,  gives — 

Conifers     .  •      . 

Oaks. 

Other  broadleaved  trees 
Cohn — Oaks 

Poplars     . 
Caspary— Oaks    . 

Poplars 


15 

54 

-iO 

14)  out  of  40  trees 

12)'     struck. 

15 1  out  of  93  trees 

34)      struck. 


C.  Hess  (1896)  found  that  pyramidal  poplar  is  often  struck, 
and  that  in  eight  out  of  the  ten  cases  he  observed  lightning 
passed  from  the  tree  to  a  neighbouring  building.  Poplars  should, 
therefore,  not  be  too  near  to  buildings. 

According  to  Collodon,  near  the  lake  of  Geneva,  poplars 
rarely  suffer  from  lightning. 

In  the  "  Revue  des  Eaux  et  Forets,"*  the  results  are  given 
of  15  years'  experience  in  a  forest  composed  as  follows : — 


0;ilc. 

Beech. 

spruce. 

riiie. 

Otla 

Percentage  of  trees     . 

11 

70 

13 

G 



Trees  struck  by  Hghtning 

159 

21 

20 

59 

20 

Pielative  frequency     . 

48 

1 

5 

33 

— 

This  agrees  generally  with  the  results  obtained  in  Detmold. 

Similar  observations   were   made   in   the   Bavarian    State 
forests,  1887—1890. 


Trees  struck. 

Percentage  of  area  occupied 
by  each  species. 

Scots  pine     . 

.     181 

30-8 

Spruce  .... 

.      88 

\  41-50 

Silver-fir 

.       67 

Oaks      .... 

.       61 

1-82 

Soft  woods  (broadleaved) 

11 

2-41 

Larch    .... 

7 

0-58 

Beech    .... 

7 

10-79 

Total     . 

.     372 

Total     .  87-90 

• 

•  February,  1 81)4.  p.  7s. 


664  PROTECTION   AGAINST    LIOHTNINCx. 

In  the  Saxon  State  forests,  in  1897,  the  first  year  that  such 
observations  were  made,  it  was  found  that  the  danger  for  oak 
was  six  times  that  for  conifers. 

On  the  whole,  from  these  observations  it  is  evident  that 
local  circumstances  such  as  proximity  of  lakes,  dampness  of 
soil,  density  of  growth,  healthy  or  unhealthy  condition  of 
trees,  afifect  the  question  whether  one  species  will  be  more 
liable  to  attack  than  another  in  any  particular  locality. 

Some  experiments  as  regards  the  conductivity  of  electricity 
by  wood  have  been  recently  made  by  Jonesco,  of  the  Wiirttem- 
berg  Society  of  Natural  Science.  In  these  experiments  Holz's 
electric  machine  was  used. 

1  turn  passed  the  spark  through  oakwood, 

12  to  20  turns  through  beech, 

5  turns  through  poplars  and  willows. 

The  use  of  heartwood  or  sapwood  and  state  of  dryness  of 
the  wood  made  no  difference  in  the  results,  but  the  richness 
of  beech  in  oil  prevents  its  being  a  good  conductor. 

Fischer  ("Biologie  der  Holz  Gewiichse"*)  distinguishes 
between  oily  trees  and  starclnj  trees.  In  oily  trees,  the  elaborated 
starch,  during  winter  and  spring,  becomes  converted  into  oil  and 
passes  into  the  pith,  wood,  and  bark.  Part  of  the  starch  in  the 
bark  also  becomes  converted  into  glucose.  In  the  starchy 
trees,  the  reserve  starch  remains  unaltered  between  autumn 
and  May. 

The  green  wood  of  the  oily  trees  (beech,  walnut,  Ijirch, 
lime),  especially  wood  very  rich  in  oil,  is  a  bad  conductor  of 
electricity.  The  starchy  trees  (oak,  poplar,  maples,  ash,  elm, 
sorhm)  are  good  conductors.  Conifers  are  intermediate,  the 
Scots  pine  in  summer  being  as  poor  in  oil  as  the  starch  trees, 
but  rich  in  oil  during  winter.  After  the  oil  had  been  extracted 
from  wood  of  fatty  trees  by  means  of  ether  they  became  as 
good  conductors  as  typical  starchy  trees. 

StarcJiy  trees  are  therefore  more  in  danger  from  Uyhtniiig  titan 
oily  trees. 

c.  Locality. 

Dami)  soils  conduct  electricity  well,  but  in  dry  places  when 
the  lightning  has  reached  the  ground,  it  may  spread  from 

*   I'liugslieiin's  '■  Jahibuch  f'lir  wissenschaftliche  Butauik,"  Band  xxii.,  p.  73. 


DAMAGE    DONE.  665 

root  to  root  of  neighbouring  trees  and  cause  them  to  die  in 
groups. 

It  is  probable  that  when  sound  well-conducting  trees 
growing  on  damp  soil  are  struck  the  lightning  passes 
rapidly  down  to  the  earth  without  causing  much  breakage, 
but  that  when  rotten  wood  is  met  with,  which  is  a  bad 
conductor,  the  crown  or  branches  may  be  broken,  or  even 
the  tree  set  on  fire. 

The  relative  frequency  with  which  trees  are  struck  on 
different  soils  in  Lippe-Detmold  is  given  below  : — 

Loam 220 

Sand 118 

Clay 84 

Keuper  marl       ....       35 

Calcareous  soil    ....       28 

Flooded  land      ....         4 

This  may  explain  the  greater  danger  to  trees  from  lightning 

in  North  Germany  as  compared  with   South  Germany  and 

Austria.     It  is  also  possible  that  loam  and  sand,  producing 

most   oaks   and    Scots    pine,    have   high    figures,    while    on 

calcareous  soil  the  beech  predominates. 

Trees  are  said  to  be  more  frequently  struck  by  lightning  in 
badly  wooded  plains  than  in  well-wooded  mountain  districts. 
This  is  true  for  the  bare  middle  Rhine  valley  and  its  adjoining 
wood-stocked  hills. 

It  is  supposed  that  dense  forests  act  as  conductors  and 
allow  electricity  to  pass  gradually  from  the  earth  to  the 
clouds,  whilst  clearing  the  land  of  forests  increases  the  heat 
of  summer  and  hinders  the  neutralisation  of  the  electricity  of 
the  clouds. 

d.  Density  of  Crop  and  Condition  of  Tires. 

Lightning,  according  to  Hess,  strikes  in  preference  trees 
standing  free  from  their  neighbours,  those  in  avenues  and  on 
the  border  of  a  wood  and  also  trees  dominating  over  the  rest 
of  a  wood. 

Sound  trees  are  more  frequently  injured  than  unsound 
trees,  but  dry  trees  may  be  struck,  and  stag-heacfed  oaks 
are   frequently  smashed  to   pieces   by  lightning.      Thus,   a 


666  PROTECTION   AGAINST    LIGHTNING. 

positively  electrified  cloud  induces  the  separation  of  the 
electricity  in  a  tree,  driving  the  positive  electricity  into  its 
roots  and  the  earth,  whilst  the  tree  becomes  charged  with 
negative  electricity.  The  strength  of  this  charge  becomes 
weakened  by  gradual  discharge  into  the  atmosphere  from  the 
numerous  twigs  and  leaves  in  the  crown  of  a  vigorous  tree. 
On  the  contrary,  a  tree  with  many  dry  branches  and  scanty 
foliage  becomes  thoroughly  charged  with  negative  electricity, 
and  when  struck  by  lightning  receives  a  more  violent  shock 
than  a  sound  tree. 

e.  Season. 

In  Central  and  Western  Europe  the  most  frequent  thunder- 
storms are  in  June  and  July,  between  3  and  5  p.m.  or  1  and 
2  a.m.  These  storms  usually  pass  from  S.W.  to  N.E.  or 
from  W.  to  E. 

In  the  case  of  heavy  rain  before  the  lightning-stroke,  the 
trees  become  better  conductors,  and  are  more  liable  to  be 
struck. 

The  average  rate  at  which  thunder-storms  travel  in  South 
Germany  is  given  by  C.  Lang,  the  result  of  five  years'  obser- 
vation, as  25^  miles  an  hour,  which  agrees  with  French 
observations.  In  1886,  the  greatest  rate  was  49  miles,  the 
least  6|  miles,  an  hour. 

3.  Register  of  Damage  by  Lightning. 

The  frequency  of  thunder-storms  in  Central  Europe  decreases 
as  the  latitude  increases  and  in  proximity  to  the  Atlantic 
Ocean,  as  the  following  average  figures  show  : — 


Number  of 

Thunder-storms 

Name  nf  Country. 

pel 

annum. 

Italy 

.     38 

Austria       .... 

.     23 

Hungary,  Baden,  Wiirttemberg 

.     22 

Silesia,  Bavaria,  and  Belgium 

.     21 

Holland      .... 

.     18 

Saxony  and  Brandenburg  . 

.     17 

France  and  South  Kussia   . 

.     16 

Spain  and  Portugal    . 

.     15 

DAMAGE    DONE.  667 

Number  of  Thunder-storms 
Name  of  Country.  per  annum. 

Schleswig-Holstein,  Mecklenburg,  Hannover, 

West  Prussia 13 

North  Piussia 10 

Little  Piussia       ......  9 

Sweden  and  Finland 8 

England  and  Swiss  Alps     ....  7 

Norway 4 

There  has  been  no  increase  in  the  last  thirty  years  in  the 
number  of  thunder-storms  in  Germany,  Austria  and  Switzer- 
land, but  in  most  other  European  countries  their  frequency 
has  increased  almost  threefold,  and  this  is  considered  to  be 
due  to  increase  of  railways,  metallic  roofs  and  pipes  for  gas, 
water,  etc.,  inside  houses.  The  increased  smoke  from  factories 
also  favours  thunder-storms. 

Some  interesting  facts  regarding  trees  killed  by  lightning 
are  given  below. 

1848  (early  in  July) :  Fifty-two  Scots  pines  about  125 
years  old  were  killed  by  lightning  at  Sprillgehorge,  in 
Hannover,  only  one  of  them  being  directly  struck. 

1865  (spring) :  Seventy  60-year-old  spruce  trees,  only  one 
of  which  was  struck,  were  killed  by  lightning  in  the  Ilarz 
Mountains. 

1868  (11th  May)  :  A  green  spruce  tree  struck  and  burned  in 
Kothenwald,  in  Eeuss. 

1876  (17th  July) :  After  a  long  drought,  a  dried-up  moor 
stocked  with  a  thicket  of  11 -year-old  Scots  pines  and 
spruce  was  fired  by  lightning  at  Aurich,  near  Neuenwalde. 

1887  (summer) :  Two  lightning  strokes  about  70  feet 
apart  killed  all  the  trees  on  about  one-fifth  of  an  acre  stocked 
with  Scots  pines  and  a  few  beech  near  Neustadt. 

1887  (15th  July) :  Seventy-two  large  spruce  trees  were 
killed  by  one  stroke  of  lightning  at  Briickenberg.  It  was 
clearly  seen  from  marks  on  the  branches  that  the  lightning 
had  passed  from  tree  to  tree. 

1891  (summer)  :  On  a  road  in  Ober  Hesse  lightning  struck 
twelve  wooden  posts  (spruce  poles  8  feet  high  and  2  inches  in 
diameter)  that  were  supporting  plants  of  sycamore  and  oak 


Gt5S 


PROTECTION   AGAINST    LIGHTNIN(i. 


planted  along  100  metres  of  roadway.  No  injury  was  done  to 
the  living  plants,  but  all  the  supports  were  struck  and  split, 
the  lightning  passing  through  the  ground  from  one  post  to 
the  other. 

1895  (10th  June)  :  At  Bockling,  in  Graf  Schulenburg's 
forest,  lightning  set  fire  to  a  crop  of  IS-j-ear-old  silver-fir, 
the  fire  extending  over  about  sixty  acres. 


i-iu-k  liy  li,l:lltlllll^^  St.  Aiiiami 
23id  July,  1S9G. 


r  \';ili.luic.iilK;^, 


PART  YL 

PROTECTION   AGAINST   CERTAIN   DISEASES   OF 
FOREST   TREES. 


671 


CHAPTER  I. 

GENERAL  ACCOUNT  OP  THE  DISEASES  OF  PLANTS. 

1.  Definition. 

A  FOEEST  plant  is  said  to  be  diseased  when,  owing  to 
disturbances  in  the  functions  of  its  organs  and  in  the 
chemical  or  physical  processes  going  on  within  them,  it 
assumes  such  a  condition  that  it  is  hindered  from  further 
useful  development  and  may  consequently  die,  either  wholly 
or  in  part.  Disease  therefore  causes  blanks  in  woods  of  all 
ages,  and  also  loss  of  wood-increment  and  consequent 
reduction  in  their  value. 

2.  Causes  of  Disease. 

Many  different  causes  of  disease  in  forest  trees  may  occur, 
for  instance,  old  age,  injuries  by  men  and  animals,  injuries 
by  parasitic  plants  (weeds  and  fungi),  by  atmospheric  agencies. 
Disease  is  also  due  to  certain  local  circumstances,  such  as  soils 
too  poor  in  the  chemical  compounds  necessary  for  plant-life, 
soils  too  dry  or  very  wet,  too  compact  or  too  loose,  etc. 

Although  much  progress  has  been  made  during  the  last 
twenty  years  in  the  study  of  the  diseases  of  forest  trees,  a 
wide  field  is  still  open  for  discovery  in  this  respect. 

3.  Classification  of  Diseases. 

The  diseases  of  forest  plants  may  be  grouped  according  to 
their  origin,  the  nature  of  the  organs  which  are  attacked,  the 

*  A  capital  account  of  the  conditions  of  environment  which  encourage  disease 
in  a  plant  is  given  in  the  Proceedings  of  the  Royal  Soc.,  vol.  47,  "  The  Croonian 
Lecture,"  by  H.  Marshall  "Ward. 

Hartig,  Dr.  Robert,  "  Lehrbuch  der  Baumkrankheiten."     Berlin,  188!>. 

Frank,  Dr.  B.,  "  Die  Krankheiten  der  Pflanzen,"  3  vols.,  1896. 

Soraner,  Dr.  Paul,  "  Zeitschrift  fiir  Pflanzerkraukhciten."  S  uttgart.  This 
perio^lical  commenced  in  1891 


672  PROTECTION   AGAINST    DISEASES. 

progress  of  the  disease  and  its  importance  in  forestry.     These 
four  headings  have  been  considered  in  the  following  list : — 

1.  Diseases  arising  from  physical  agency  (frost-crack,  bark 
blister,  etc.)  and  those  from  lihysiolog'wal  causes,  such  as  red 
and  white  rot. 

2.  Local  diseases,  such  as  of  the  roots,  or  of  the  stem,  bark, 
buds,  leaves  or  shoots,  or  of  the  inflorescence  and  fruits  of  the 
trees. 

3.  Acute  or  rapidly  developing  diseases,  or  chronic  diseases 
which  develop  slowly. 

4.  Diseases  which  merely  cause  loss  of  increment,  and 
others  which  affect  the  economic  value  of  the  wood,  the  latter 
consisting  either  in  an  abnormal  growth  of  otherwise  healthy 
woody  tissue,  such  as  burrs,  twisted  fibre,  etc.,  or  in  an 
unhealthy  state  of  the  tissues,  as  in  red  or  white  rot. 

The  worst  kinds  of  damage  to  forest  plants  by  men, 
animals,  plants,  and  atmospheric  agencies  have  been  already 
dealt  with  in  the  preceding  chapters  of  this  book.  For  the 
study  of  abnormal  growth  in  healthy  wood-tissues,  the  reader 
is  referred  to  treatises  on  Forest  Utilisation.  In  the  following 
pages  wuU  be  described  cevtain  diseased  conditions  which 
could  not  well  be  classified  under  any  of  the  foregoing  heads 
and  are  limited  to  the  following: — red  rot,  white  rot,  stag- 
Jteadedness,  abnormal  needle- shedding,  and  damage  by  factory 
fumes. 


673 


CHAPTER  IL 

RED    ROT.* 

1.  Description. 

Red  rot  is  a  decomposition  of  wood,  by  which  its  elemen- 
tary organs  are  gradually  detached  from  one  another,  and  it 
becomes  eventually  converted  into  a  loose-textured  mass,  at 


Fig.  294. — Section  of  a  spruce  suffering  from  red  rot, 

a  Sound  wood,     b  Discoloured  wood  where  decay  has  commenced. 

c  Eotten  wood. 


first  reddish-brown  and  passing  through  a  dark  brown  con- 
dition into  a  peaty  substance  resembling  humus.  Fre- 
quently whitish  mycelia  may  be  noticed  traversing  the  \YOod 
longitudinally. 

Eed  rot  (Fig.  294)  occurs,  according  to  its  position,  as  root, 
stump,  stem,  or  branch-rot.  A  transverse  section  through  the 
rotting  wood  shows  a  great  variety  in  the  phenomena  and 
course  of  this  disease,  often  in  the  same  tree.     Either  certain 

*  Willkomm,  Dr,  Moritz, ''  Die  Mikrospischen  Feinde  des  Waldes,"  Dresden, 
1866,  pp.  31  and  21'J.  Hartig,  Dr.  R.,  "  Die  Rotfaule  der  Fichte,"  "  Monatschrift 
fr.  das  Forstund  Jagdwesen,"  1877,  p.  97,  an  excellent  and  comprehensive  work. 

F.P.  X   X 


674  PROTECTION    AGAINST    DISEASES. 

annual  zones  or  groups  of  annual  zones  of  wood  between  the 
heart  and  sapwood  are  attacked,*  or  the  disease  occurs  in 
patches,  or  attacks  merely  the  central  zones  of  the  tree  or 
branch.  The  sapwood  is  never  attacked  by  red  rot.  The 
rotten  wood  may  eventually  be  completely  decomposed,  when 
it  disappears,  leaving  a  hollow  cylinder,  in  place  of  the  heart- 
wood,  and  this  frequently  without  involving  the  death  of  the 
tree.  Sometimes  the  innermost  portion  of  the  stem  remains, 
forming  a  thin  columnal,  hard  strand  of  wood  united  with  the 
sapwood  here  and  there  by  similar  strands  where  branches 
have  been  enclosed  in  the  wood. 

The  commencement  of  the  disease  may  be  recognised  by  a 
light  violet  or  reddish  colour  of  the  wood,  and  by  the  porous 
spring  zones  being  attacked  before  the  harder  autumn  zones. 

2.  Modifying  Factors, 
a.  Species. 

Eed  rot  occurs  in  almost  every  species  of  forest  tree. 
Among  broadleaved  species  oaks  and  elms  suffer  most,  and 
among  conifers  the  spruce  and  Scots  pine.  The  disease 
usually  commences  at  the  roots  of  spruce  trees. 

Eoot  rot  usually  spreads  upw^ards  through  the  heartwood  to 
the  branches.  It  may,  however,  on  the  contrary,  gradually 
descend  from  the  branches  through  the  stem  to  the  roots. 

I).  A(je  of  Tree. 

Eed  rot  is  a  normal  condition  of  very  old  trees,  but  a  disease 
in  the  case  of  young  trees.  It  has  been  observed  in  the  spruce 
from  the  age  of  10  years  and  upwards. 

c.  LocaUty. 

Wood  may  become  rotten  in  all  kinds  of  localities,  but  certain 
conditions  of  the  soil  predispose  trees  to  this  disease.  Such 
are  —  soils  very  rich  in  humus,  calcareous  soils,  soils  very 
compact  or  wet  and  cold,  such  as  clays  and  peats  which  are  not 

•  Termed  Mondring  in  German  and  lunure  in  Freneh. 


RED    ROT.  675 

properly  aerated,  or  where  an  impermeable  substratum  occurs 
at  3,n  inconsiderable  depth  below  the  surface  of  the  ground. 
Wood  also  readily  rots  in  places  where  cattle  rest  at  midday, 
owing  to  the  excrement. 

d.   Treatment  of  Woods. 

A  dense  condition  of  a  wood,  especially  in  moist  or  wet  locali- 
ties, favours  the  evil.  Tapping  for  turpentine,  barking  by 
game,  and  other  injuries,  such  as  pruning  living  branches 
without  tarring,  frequently  give  rise  to  the  first  symptoms  of 
red  rot  in  wood,  especially  when  the  trees  are  growing  in 
localities  predisposing  them  to  disease. 

3.  Causes. 

Widely  differing  and  frequently  contradictory  hypotheses 
have  been  started  to  explain  the  origin  of  red  rot.  Usually 
it  is  attributed  to  external  circumstances,  such  as  unfavourable 
localities,  injuries,  etc.,  without  further  inquiry  into  its  possible 
causes. 

The  first  scientific  inquiry  into  the  cause  of  red  rot  is  found 
in  the  works  of  Willkomm  (1866),  who  designated  a  microscopic 
fungus  as  the  sole  origin  of  the  disease.  He  named  this  fungus 
Xenedochus  Ugniperda,  and  another  allied  form  which  springs 
from  it  Rhynchomyces  violacctis,  which  causes  the  bluish  colour 
in  rotting  wood. 

The  question  as  to  the  origin  of  red  rot  was  not  by  any 
means  solved  by  Willkomm's  researches,  as  he  merely  proved 
the  presence  of  the  above  fungi  in  rotten  wood,  but  did  not 
make  experiments  to  infect  sound  wood  by  means  of  their 
spores,  so  that  it  remained  doubtful  whether  the  fungi  were 
the  causes  or  merely  the  consequences  of  red  rot. 

Eo])ert  Hartig,  in  1874,  solved  this  question  by  proving  that 
red  rot  in  the  case  of  spruce,  Scots  pine,  oaks,  etc.,  really  arose 
from  infection  by  parasitic  fungi.  Later  on,  in  1877,  he  further 
proved  that,  at  least  for  the  spruce,  unfavourable  soils  and 
external  injuries  also  induced  the  disease.  As  we  have  already 
in  chapter  III.,  part  II.,  discussed  the  infection  of  trees  by 
fungi,  we  have  now  only  to  deal  with  the  two  latter  cases. 

X  X  2 


676  PROTECTION   AGAINST   DISEASES. 

a.  Unsuitable  Sails. 

The  kinds  of  soil  which  induce  red  rot  in  the  roots  of  tr6es, 
and  chieflj'  in  their  deeper-lying  roots,  are  generally  peaty 
humus,  calcareous  soils,  soils  containing  pans  or  impenetrahle 
suhstrata  of  ochrous  iron  ore,  lignite,  clay  or  loam,  also  very 
fine  sand,  not  infrequently  found  in  the  lias  formations  in 
Germany.  Such  subsoils  interfere  with  aeration  of  the  surface 
soil,  the  oxygen  so  necessary  for  the  roots  of  trees  being  unable 
to  reach  them  in  sufficient  quantity.  This  is  due  to  the  fact 
that  the  air  in  soils  too  compact  or  waterlogged  is  gradually 
deprived  of  its  oxygen  by  the  roots  of  the  plants  growing  on 
it,  and  by  the  decomposition  of  the  litter ;  this  loss  of  oxygen 
is  not  sufficiently  replaced  by  the  admission  of  fresh  air  to  the 
soil.  The  denser  the  wood,  the  faster  the  evil  progresses  ;  fungi 
also  accelerate  the  disease. 

In  the  North-west  German  loamy  heather  tract,  where  pan 
is  very  prevalent,  more  than  75  per  cent,  of  the  Scots  pine 
woods  sufter  terribly  from  red  rot.  Spruce,  however,  thrives 
there. 

This  form  of  red  rot  is  more  prevalent  with  larch  and  some- 
times with  Scots  pine  than  with  spruce,  for  the  roots  of  the 
larch  as  well  as  those  of  Scots  i^ine  penetrate  more  deeply 
into  the  soil,  and  therefore  rot  more  readily  than  those  of 
spruce  that  spread  in  all  directions  in  the  upper  layers  of 
the  soil. 

Scots  pine,  however,  when  grown  on  shallow  soils,  can  pro- 
duce superficial  roots  like  those  of  spruce,  whilst  experience  in 
"Windsor  Forest  shows  that  larch  growing  on  a  gravelly  soil 
above  a  pan  always  gets  red  rot,  and  this  is  confirmed  by 
A.  D.  Webster,*  who  states  that  larch  always  gets  red  rot 
when  grown  on  gravelly  soils. 

h.  External  Injuries. 

Trees  are  frequently  wounded  during  the  felling,  conversion, 
and  transport  of  timber.  Wounds  also  arise  owing  to  forest 
pasture,  game,  mice,  insects,  from  pruning  green  branches,  or 
from  meteoric  influences,  frost-crack,  bark-scorching,  windbreak 

*  "  Practical  Forestry."    William  Rider  &  Son,  Loudon,  2ud  edition,  1895. 


RED    ROT.  677 

or  snowbreak,  hail,  etc.  Wherever  the  living  tissues  of  the 
wood  are  exposed,  especially  where  the  wounds  are  not  clean- 
cut,  moisture  penetrates  into  them,  unless  they  are  protected 
by  antiseptic  substances,  such  as  a  natural  flow  of  turpentine, 
or  by  tar.  With  the  entrance  of  water  into  the  tissues,  certain 
chemical  changes  take  place  in  their  contents,  and  local  disease 
may  arise.  Spores  of  fungi  also  penetrate  the  tissues,  such  as 
the  spores  of  species  of  PolyjJoms  in  the  upper  parts  of  the 
tree,  or  of  Armillarea  mellea,  etc.,  in  its  roots. 


4.  Damage  done. 

Red  rot  affects  the  technical  value  of  wood  in  proportion  to 
its  extent  and  degree  of  development,  and  to  the  innate  value 
of  the  tree  which  is  attacked.  Wood  affected  by  red  rot  cannot 
be  used  as  timber,  and  is  only  of  slight  value  as  fuel.  The 
worst  form  of  this  disease  is  when  it  attacks  a  tree's  roots,  as 
it  then  generally  affects  the  whole  stem ;  the  least  dangerous 
form  is  in  the  branches. 

It  is  not  rare  in  spruce  woods  60 — 70  years  old  to  find  that 
10  per  cent,  of  the  trees  are  rotten,  whilst  the  liability  of  rotten 
trees  to  windbreak  and  snowbreak  is  another  cause  of  disaster. 

5.   Treatment  of  the  Disease. 

The  rules  for  combating  red  rot  depend  on  the  cause  of  the 
disease. 

a.   Wltoi  due  to  Unstu/able  >Sy/7.s\ 

Great  care  should  be  taken  in  planting  to  allot  the  species 
of  trees  to  soils  suitable  for  their  welfare. 

Remove  densely  growing  mosses  and  other  unfavourable 
vegetation  from  damp  mountain  soils. 

Drain  and  work  up  the  superficial  layers  of  compact  soils. 

In  wet  soils  which  cannot  be  drained,  plantations  should  be 
made  on  mounds  or  ridges. 

On  calcareous  soils  broadleaved  species  should  be  intermixed 
with  Scots  pine  and  spruce  ;  low  rotations  of  60 — 70  years 
should  be  adopted  for  spruce. 


678 


PROTECTION   AGAINST   DISEASES. 


h.   When  due  fo  Injuries. 

Great  care  should  be  taken  during  timber-fellings  and 
transport. 

Pruning  of  green  branches  should,  if  possible,  be  avoided,  or 
restricted  to  branches  under  4  inches  in  diameter  ;  all  wounds 
made  by  pruning  should  be  smeared  with  tar. 

All  rotten  trees  and  stumps  should  be  speedily  removed 
from  the  forest. 

All  measures  dictated  by  forest  protection  should  be  strictly 
followed  in  order  to  prevent  injuries  to  the  trees. 


Fig.  29.'). — Kn>st-cr;nk  in  an  oak  tree.     Dillenlnin 
Photo,  by  E.  E.  Marsden. 


679 


CHAPTER  III. 

WHITE   ROT.* 

White  rot  is  distinguished  from  red  rot  by  the  colour  of 
the  decomposing  wood,  which  is  of  a  whitish  instead  of  a 
reddish  hue.  It  is  commoner  among  hroadleaved  species 
(beech,  hornbeam,  maple,  oak,  chestnut,  poplars,  and  willows) 
than  among  conifers ;  it  is  probably  due  to  several  causes 
combined,  but  appears  to  be  chiefly  caused  by  fungi.  White 
rot  is  rarer  than  red  rot,  and  its  course  less  rapid.  The 
protective  measures  to  be  taken  are  similar  to  those  against 
red  rot. 

*  Books  referred  to  under  "  Red  rot."     Also  see  p.  440  of  the  present  work. 


180 


CHAPTER  IV. 

STAG-HEADEDNESS. 

1.  Description  and  Causes. 

It  has  been  already  stated  that  red  rot  frequently  attacks 
very  old  trees,  rendering  their  stems  hollow,  but  another  sign 
of  excessive  old  age  is  the  death  of  some  of  the  topmost 
branches  of  a  tree,  which  has  no  longer  sufficient  vigour  to 
pump  water  so  far.  The  death  of  these  branches  causes  them 
eventually  to  break  off,  and  atmospheric  moisture  is  then 
admitted  into  the  trunk,  and  rot  commences  and  penetrates 
downwards  towards  the  roots.  Stag-headedness  may,  how- 
ever, occur  in  immature  trees,  and  is  then  due  to  one  of  the 
following  causes : — 

(a)  When  trees  which  have  been  growing  in  a  dense  wood 
are  suddenly  exposed  as  standards,  as  in  natural  regeneration 
in  high  forest,  or  after  the  felling  of  the  underwood  in 
coppice-with-standards,  the  surface  moisture  of  the  soil  may 
be  reduced  and  the  trees  consequently  become  stag-headed. 
In  some  cases  such  trees,  and  especially  oaks,  having  com- 
paratively soft  bark,  owing  to  their  formerly  protected  state 
in  a  dense  wood,  j)ut  out  numerous  epicormic  branches  from 
the  dormant  buds  along  their  stems,  which  absorb  the  sap 
that  would  otherwise  reach  their  crowns.  This  tends  to  cause 
stag-headedness,  which  may,  however,  be  obviated  by  one  or 
two  prunings  of  the  epicormic  branches,  until  the  bark 
becomes  too  hard  for  them  to  form. 

{h)  In  forests  of  lightdemanders  such  as  oak,  larch,  ash, 
Scots  j)ine,  the  soil  may  be  completely  sheltered  by  the  crop 
up  to  a  certain  age,  but  after  40 — 60  years  the  leaf- canopy 
ceases  to  be  sufficiently  close  to  protect  the  soil  from  the  sun, 
which  gradually  dries  it  up,  and  thus  causes  stag-headedness 
in  the  trees,  unless  the  soil  be  protected  by  an  underwood  of 
shadebearers.      This    result    follows    more   rapidly    on    hot 


STAG-HEADEDNESS. 


681 


aspects,  and  the  more  superficial  the  soil,  and  the  more 
porous  the  subjacent  rock,  such  as  chalk  or  coarse  gravel,  and 
the  less  the  rainfall  and  relative  humidity  of  the  air  in  the 
locaHty. 

(c)  Any   interruption  of   the   leaf-canopy  in  forests  of  all 


"  Scots  j.iue,  AVindsor  Forest. 


kinds   may  cause  deterioration  of   the    soil   and    consequent 
stag-headedness. 

((/)  Drainage  also,  by  lowering  the  level  of  water  in  the 
soil  of  a  forest,  may  deprive  formerly  thriving  trees  of  suffi- 
cient moisture,  which  their  roots,  adapted  to  reach  water 
near  the  surface,  can  no  longer  absorb  in  sufficient  quantity. 
Trees  thus  affected  may  become  stag-headed.  This  happened 
on  a  large  scale  with  oaks  growing  in  the  Wild  Park  at 
Carlsruhe,   owing  to  the  rectification   of   the   course   of   the 


PROTECTION   AGAINST   DISEASES. 

Tihine,  and  consequent  lowering  of  the  water-level  in  the 
soil.  A  similar  result  followed  drainage  in  Windsor  Park 
with  regard  to  some  of  the  elms  in  the  Long  Walk  avenue, 
and  it  Is  not  uncommon  with  alder-woods  after  drainage. 
Continual  and  excessive  removal  of  litter  from  a  forest  may 
cause  stag-headedness  in  immature  beech  forest.*  It  has 
been  noticed  in  certain  two-storied  coniferous  forests  in 
North  America  after  the  upper  stage  of  trees  had  been  felled, 
and  the  sun  a-llowed  to  dry  up  the  soil-covering,  that  the 
lower  stage,  the  roots  of  which  had  spread  superficially  in 
the  layer  of  d|fead  leaves  and  humus,  became  liable  to  stag- 
headedness  an(d  death. 

(e)  Stag-headedness  in  the  Scots  pine  may  be  caused,  as 
stated  on  p.f'441,  by  the  fungus  Peridermium  Piiii,  such  trees 
being  termed  "  foxy"  (Fig.  293). 

It  is.-  found  that  though,  in  the  case  of  conifers,  stag- 
hea(!iedness  is  speedily  followed  by  the  death  of  the  tree,  and 
beech  also  speedily  succumbs  when  similarly  affected,  yet 
that  some  other  broadleaved  species,  and  especially  oak,  may 
remain  stag-headed  for  many  decades  without  dying,  although 
the  technical  value  of  their  timber  rapidly  deteriorates,  and 
their  trunks  may  become  completely  hollow. 

One  of  the  worst  instances  of  stag-headedness,  on  a  large 
scale,  may  be  seen  in  the  State  forest  of  Compiegne.  Between 
1775  and  1790,  an  area  in  that  forest  of  about  6,000  acres 
was  clear-cut  and  planted  by  a  contractor  named  Panellier 
with  pure  pedunculate  oaks.  The  soil  was  either  very  sandy, 
or  a  stifiish  clay,  but  wherever  on  adjacent  land  oak  is  mixed 
with  beech  and  hornbeam,  excellent  oaks  are  produced.  In 
the  Panellier  plantations,  however,  now  100  to  180  years  old, 
the  ground  is  generally  bare  of  underwood  under  the  oaks. 
The  bark  of  the  oak  trees  is  yellow  with  lichens  and  they  are 
nearly  all  stag-headed  and  have  ceased  to  grow,  presenting  a 
deplorable  picture.  There  are  magnificent  sessile  oak  trees 
more  than  twice  the  age  of  the  Panellier  oaks  on  sandy  hills, 
called  Les  Hants  Monts,  close  to  these  pure  pedunculate 
plantations,  but  these  sessile  oaks  are  mixed  with  beech. 

•  Fiirst's  "  Waldschutz,"  tnuislatwl  by  J.  Nisbet,  p.  '>'.K     Edinburgh,  18'J3 


STAG-HEADEDNESS.  688 

2.  Treatment. 

a.  Preventive. 

i.  Maintain  the  soil-covering  of  dead  leaves,  moss,  etc.,  in 
order  that  the  soil  may  not  lose  its  moisture. 

ii.  Keep  up  a  dense  leaf-canopy,  especially  where  the  soil 
is  shallow  and  liable  to  dry  up,  and  where  the  subjacent  rock 
is  of  a  porous  nature  (chalk,  gravel,  etc.). 

iii.  Underplant  all  high  forests  of  lightdemanders  with 
a  shadebearer,  such  as  beech  or  silver-fir,  as  soon  as  grass 
or  other  herbage  appears  on  the  soil,  and  fill  up  with  shade- 
bearers  any  gaps  which  may  have  occurred  in  a  forest  owing 
to  windfall,  or  other  injurious  causes.  Underplanting  oak 
forest  with  spruce  may  cause  stag-headedness,  on  account  of 
the  quantity  of  moisture  the  spruce  absorbs. 

iv.  Do  not  plant  spruce,  alder,  ash  or  pedunculate  oak  in 
dry  localities.  The  sessile  oak  will  thrive  on  well -drained 
hillsides,  where  it  is  hopeless  to  plant  the  pedunculate  oak. 

V.  Avoid  draining,  unless  it  is  absolutely  necessary. 

vi.  High  forest  is  more  suitable  tiian  coppice-with-standards 
in  dry  localities  and  those  with  superficial  soil  or  above  a 
porous  rock. 

vii.  When  epicormic  branches  appear  on  oaks  and  other 
standards  in  coppice-with-standards,  or  on  standards  left  after 
regeneration  in  high  forest,  they  should  be  pruned  off  before 
the  next  spring.  It  may  be  necessary  to  repeat  the  operation, 
but  after  two  seasons  in  the  open  the  bark  of  the  standards 
becomes  hardened,  and  the  epicormic  branches  do  not  generally 
reappear.  In  any  case  the  stems  of  the  standards  will  be 
gradually  sheltered  again  by  the  rising  underwood,  which  will 
effectually  kill  any  epicormic  branches  still  on  the  tree. 

The  appearance  of  epicormic  branches  on  oak  trees  growing 
in  a  dense  wood  is  a  sign  of  disease,  and  such  trees  should  be 
gradually  removed  in  the  fellings,  as  they  will  certainly  become 
stag-headed. 

b.  Remptlial. 

As  a  rule  no  remedy  can  be  adopted  when  forest  trees  Ijecome 
badly  stag-headed,  the  only  measure  to  be  followed  being  to 
fell  them  and  utilise  their  timber  before  it  becomes  further 


684  PROTECTION   AGAINST   DISEASES. 

deteriorated.  Slightly  stag-headed  ornamental  trees  in  parks 
or  avenues  may,  however,  be  given  a  fresh  start  in  life  by 
trenching  the  ground  under  their  crowns,  breaking  up  any 
impermeable  stratum  under  their  roots,  and  manuring  them 
with  rich  leaf-mould.  Stag-headed  trees  may  also  be  pollarded ; 
the  reduced  length  of  stem  may  then  enable  the  roots  to 
nourish  the  pollard  shoots  sufficiently  to  prolong  the  life  of 
the  tree  for  several  decades. 

3.  Addendum. 

The  death  of  trees  by  "  bleeding  to  death,"  a  popular  phrase, 
is  not  uncommon  with  elms.  The  bark  splits  off.  in  the 
spring  in  flakes  from  a  tree  which  appears  to  be  quite  healthy. 
Sap  exudes  in  frothy  masses,  and  forms  a  deposit  on  the 
exposed  wood.  This  continues  throughout  summer,  and  if  the 
summer  be  a  dry  one  the  foliage  eventually  fades  and  falls  off, 
and  the  tree  dies.  In  a  case  that  occurred  in  the  very  dry 
summer  of  1906,  the  roots  of  the  tree  had  been  cut  through 
by  new  drainage  works,  the  tree  standing  between  two 
cross-roads.  Not  a  leaf  was  left  on  the  tree  by  September, 
although  it  was  quite  flourishing  in  April,  and  not  more  than 
100  years  old. 

Bleeding  and  peeling  of  the  bark  has  also  been  observed 
on  oaks  in  Cumberland  (Bray ton  Hall).  New  bark  was, 
however,  formed  under  the  flakes  of  bark  that  peeled  off. 


685 


CHAPTER   V. 

NEEDLE-CAST.* 

1.  Dcscrijytioii. 

Since  the  end  of  the  eighteenth  centiuy,  a  disease,  termed 
needle-cast  (in  German,  Schiitte),  has  been  remarked  on  young 
pines,  the  external  signs  of  which  consist  in  the  gradual 
reddish  or  reddish-l)rown  discoloration  of  their  1-  or  2-  year-old 
needles,  which  eventually  die  and  fall  off  the  plants.  As  a 
rule  these  symptoms  appear  first  in  the  spring  (Vor-ivintcr 
Schiitte),  but  not  unfrequently  also  in  the  autumn  and  early 
winter  {Nach-ninter  Schiitte),  and  in  South  Germany  the 
latter  often  haj^pens  in  years  when  the  ground  is  free  from 
snow.  A  steel-blue  or  violet  colour  of  the  1-year-old  pine- 
needles  in  autumn  is  no  sign  of  disease,  provided  yellow  or 
reddish-coloured  spots  do  not  also  occur ;  this  is  an  instance 
of  the  normal  winter-colour  of  many  evergreen  plants,  which 
disappears  as  the  thermometer  rises  in  the  spring,  and  gives 
place  to  the  ordinary  green  colouring  of  the  needles.  The 
reddish  discoloration  and  death  of  the  needles  proceeds  from 
their  tips  downwards,  and  chiefly  affects  the  lower  parts  of 
the  plant  near  the  ground.  Pines  thus  affected  resemble 
those  injured  by  drought,  but  at  the  commencement  of  the 
disease  more  or  less  regularly  distributed  dark  spots  and 
stripes  appear,  and  later,  in  May,  small  black  sporangia  of 
the  fungus  Lophoderminm  Pinastvi,  Schrad.f  Also  resin 
collects  on  the  sickly  needles.  The  worst  form  of  the  disease 
may  be  recognised  when  the  buds  become  encrusted  with 
resin  and  dry-up,  and  then  no  recovery  is  possible  for  the 
diseased  plants. 

•  Freiherr  von  Ldffelholz,  "  Beitrag  zu  eincr  kritischen  Nachweisung  iiber 
die  Schiitte-krankheit  der  Kiefer."  Berlin,  1865.  Holzner,  Dr.  Gcorg,  "Die 
Beobachtungen  liber  die  Schiitte  der  Kiefer  und  die  Winterfarbung  immergrUner 
Gewachse."     Freising.  1877. 

t  See  p.  465. 


686  PROTECTION  AGAINST   DISEASES. 

2.  Modifying  Factors, 
a.  Species 

The  Scots  jDine  suffers  most  from  needle-cast,  also  the 
black,  cluster  and  mountain  pines.  The  disease  does  not 
appear  to  have  been  as  yet  observed  on  Weymouth  pine,  nor 
on  Piiius  rigida,lSU\\.,  that  is  now  extensively  used  for  planting 
waste  land. 

b.  Aijc  of  Plaiils. 

Two-year-old  plants  suffer  most  from  this  disease,  but  3- 
to  4-  year-old  plants  may  also  be  attacked,  though  the 
danger  becomes  less  every  year.  In  years  when  the  disease 
is  very  prevalent,  weakly  plants  may  suffer  up  to  the  age  of 
15  years,  but  only  up  to  about  G  feet  from  the  ground. 

c.  LocaHtij. 

Pines  growing  in  all  kinds  of  localities  are  subject  to  this 
disease,  but  it  is  chiefly  prevalent  in  damp  or  wet  places 
exposed  to  frequent  fogs.  Thus  valleys  and  plains  suffer  more 
than  hills  and  mountains,  where  the  snow  protects  the  plants 
during  winter.  In  depressions  and  in  cold  valleys,  the  disease 
is  often  very  destructive.  As  regards  aspect,  southern  and 
western  slopes  are  most  endangered  ;  eastern  slopes  also  suffer, 
but  northern  slopes  either  not  at  all  or  only  exceptionally. 

The  soil  appears  to  have  some  influence  on  the  disease,  but 
its  effects  have  not  yet  been  clearly  explained.  Stein*  states 
that  Scots  pine  suffers  most  on  pure  sandy  soils,  but  after  all 
it  is  on  such  soils  that  most  indigenous  Scots  pine- woods  are 
found.  Von  Loffelholz  t  has  observed  that  plants  suffer  less 
on  thoroughly  cultivated  soil  than  when  the  land  has  not  been 
previously  broken  up,  and  this  may  be  due  to  the  better  root- 
systems  and  superior  hardiness  of  the  plants  in  such  cases. 
It  also  appears  that  on  peaty  soil  needle-cast  is  little  to  be 
feared,  which  fact  may  be  due  rather  to  the  treatment  of  the 
pine-forests  on  such  localities  than  to  the  nature  of  the  soil. 

*  "Ueberdie  Schiitte,"  Dr.  F.  Stein,  "  Tharaiidter  Jalubucii,"  vol.  viii,,  1852, 
pp.  208—225. 

t  The  same,  p.  41. 


NEEDLE-CAST.  687 

Emmerling*  states  that  sowings  of  1-year-old  pines  in  the 
North  German  heather-land  suffer  severely  every  year  from 
needle-cast,  whilst  those  on  the  more  favourable,  sandy  loam 
are  not  affected  by  it. 

It  is  clear  that  Scots  pine  is  affected  by  needle-cast  on  all 
kinds  of  soil,  but  that  on  loam  the  plants  are  stronger  and 
escape  the  danger  better  than  on  poor  sand. 

d.  Soil-cover iiKj. 

It  is  not  yet  decided  what  influence  the  nature  of  the  soil- 
covering  has  on  the  disease.  It  may,  however,  be  laid  down 
as  a  general  rule  that  ground  covered  with  grass  or  weeds 
is  less  liable  to  it  than  bare  localities,  but  the  favourable 
influence  of  the  soil-covering  may  be  counterbalanced  by 
other  causes. 

e.  System  of  Manaf/ement. 

Under  a  shelterwood,  the  young  pines  may  entirely  escape 
the  disease,  or  suffer  only  slightly,  and  lateral  shelter  from  old 
pine- woods  acts  favourably  by  reducing  insolation  and  radiation 
of  heat  from  the  ground.  On  large  clearings,  pines  are  almost 
always  subject  to  needle-cast.  Areas  densely  sown  late  in 
the  year  suffer  most  of  all,  when  the  individual  plants  have 
very  small  root-systems  and  thin  elongated  stems. 

/.   Weather. 

The  disease  is  most  frequent  in  March,  April  and  May, 
and  a  wide  range  of  temperature,  such  as  warm  sunny  days 
and  cold  nights  with  rime,  favours  it.  Cold,  dry  easterly 
or  north-easterly  winds  increase  the  evil.  During  cloudy, 
rainy  weather  in  spring,  the  disease  may  not  appear  at  all,  or 
only  slightly.  It  is  also  more  frequent  after  damp  winters 
with  light  snowfall  than  after  the  ground  has  been  well 
covered  with  snow. 

3.  Geographical  Range. 

The  disease  occurs  wherever  the  Scots  pine  is  cultivated, 
but  is  less  common  in  colder  countries,  such  as  Russia.     It 

*  "  Untersuchuiig  uber  die  Ureache  <ler  Kiefernschiitte  in  Schleswig-Holstein," 
by  Dr.  A.  Euimeiling  and  Dr.  G.  Loges,  "  Alig.  Frst.  u.  Jgdztg.,"  1882,  p.  13.5. 


688  PROTECTION   AGAINST   DISEASES. 

is  not  prevalent  in  the  British  Isles.  In  Germanj'  it  appears 
to  be  connected  with  the  extension  of  clear-cutting  and 
planting,  which,  since  the  end  of  the  eighteenth  century,  has 
so  largely  replaced  the  system  of  natural  regeneration  of  the 
Scots  pine.  In  the  damp,  cold  years  1850  to  1852  needle-cast 
was  widespread  and  very  destructive  in  North  Germany,  and 
again  in  1881  to  1884.  Pine-plants  which  have  once  suffered 
from  it  are  liable  to  be  again  attacked,  as  they  are  greatly 
weakened  by  the  disease. 

4.  Causes. 

Numerous  reasons  have  been  given  for  the  needle-shedding 
disease,  as  quoted  by  both  Von  Loffelholz  and  Holzner.  The 
nature  of  the  soil,  the  state  of  the  weather,  and  combinations 
of  these  have  been  cited.  Some  think  that  Lophodermium 
Pinastri  is  the  sole  cause  of  the  evil,  whilst  others  hold  it  to  be 
due  to  a  more  rapid  transpiration  of  water  by  the  needles  than 
the  roots  of  the  plants  can  supply.  It  is  therefore  probable  that 
we  have  here  to  deal  with  many  causes  acting  in  combination, 
one  with  another,  but  these  may  be  reduced  to  the  three 
following : — 

Needle-cast  fungus,  Lophodermium  Pinastri,  Schrad. 

Frosts,  and  especially  early  frosts  in  autumn. 

Insufficient  absorption  of  water  to  supply  that  transpired 
by  the  plants. 

We  have  therefore  to  deal  with  three  forms  of  the  disease: — 

(a)  Fungoidal  needle-cast. 

(h)  Frost  needle-cast. 

(c)    Dry  needle-cast. 

It  is  difficult  to  distinguish  these  causes  from  one  another, 
as  the  fungus  is  always  present,  though  frequently  it  may  be 
only  secondary. 

a.  Fum/oidal  Keedle-cast. 

The  necessary  account  of  this  disease  has  been  given  above 
on  p.  465.  Hartig,*  Pranll,  and  Tursley  have  supported  the 
fungus  theory,  but  many  phenomena  appear  which  con- 
tradict it,  for  example,  from  the  disease  beginning  at  the  points 

•  Vide  Hartig,  '■  Lehrbuch  der  Baumkrankheiten.''  Berlin,  2nd  edition,  1889, 
p.  103. 


NKEDLE-CAST.  689 

of  the  needles,  and  the  lower  parts  of  plants  suffering  most, 
and  above  all,  from  the  fact  that  the  disease  frequently  appears 
in  a  single  night,  and  is  much  commoner  in  broadcast  sow- 
ings than  in  natural  regeneration-areas.  Hess  has  frequently 
observed  the  needles  to  have  been  attacked  in  every  plant 
on  a  nursery-bed,  after  one  night's  hoar-frost  succeeded  by 
a  sunny  day,  and  this  altogether  excludes  the  action  of  the 
fungus  as  cause  of  the  disease.  Moreover,  infection  by  the 
fungus,  which  is  favoured  by  heat  and  damp,  would  be  easier 
under  a  shelterwood  than  in  the  open,  which  is  not  the  case. 
The  Lopliodermium  is,  however,  widely  spread  as  a  saprophyte 
on  dead  needles  of  pines,  as  well  as  on  those  of  the  spruce  and 

juniiDer. 

h.  Frost  Needle-cast. 

G.  Alers*  and  Nordlingerf  have  proved  that  the  disease  is 
frequently  due  to  refrigeration  of  the  plants  on  unprotected 
soil  free  from  snow,  by  radiation  from  the  soil-covering,  and 
this  opinion  has  been  adopted  by  most  practical  men.  Generally 
autumnal  frost  is  the  cause,  and  late  frost  is  not  injurious, 
except  when  there  is  a  great  difference  between  the  night- 
and  day-temperatures.  The  fact  that  on  older  plants  only  the 
lower  branches  lose  their  needles  points  to  frost  as  the  cause. 

Frost  needle-cast  is  common  after  wet,  cold  summers,  during 
which  the  young  shoots  of  the  plants  have  not  been  properly 
lignified.  Only  late  frosts  can  account  for  the  needles  turning 
red  in  the  spring,  but  experience  has  shown  that  they  are  not 
nearly  so  destructive  as  early  frosts.  The  fact  that  needle- 
cast  is  so  prevalent  on  clearings,  in  depressions  and  valleys, 
and  on  uncovered  ground  where  there  is  no  obstacle  to  radiation, 
renders  it  probable  that  in  many  cases  frost  is  the  cause  of  the 
disease. 

r.  Dry  Needle-cast. 

The  drying-up  theory  of  the  origin  of  needle-cast  was 
first  published  by  Ebermayer,t  who,  during  the  progress  of 
his  observations  of  soil-temperatures  in  the  Bavarian  forest 

•  Alers,  "  Ceutrlbl.  fr.  das  ges.  Frstw.,"  1878,  p.  1S2  ;  1898,  p.  81.  Also  1880, 
p.  156  ;  18S2,  p.  !.-)!» ;   1883,  p.  2.")9. 

t  Nordlinger,  "  Krit.  Blttr.  fr.  Frst.  u.  Jgdw.,"  vol.  xlvi.,  186.S,  p.  185. 

X  "  Die  Physikalischen  Einwirkungen  desWaldes  in  der  Abhandlung,"  "  Thar. 
Frstl.  Jhrbch.,"  vol..xxxiv.,  1884,  p.  158. 

F.P.  Y    Y 


690  PROTECTION   AGAINST    DISEASES. 

meteorological  stations,  was  led  to  adopt  this  view  of  the 
matter.  His  theory  is,  shortly,  as  follows : — The  young  Scots 
pine  plants,  owing  to  the  frequently  high  atmospheric  tem- 
perature in  March  and  April  (66°  to  77°  F.  in  the  shade), 
are  on  sunny  days  compelled  to  transpire  freely.  Although 
the  soil  is  wet  enough  to  replace  the  loss  of  water  hy  trans- 
piration, the  action  of  the  roots  is  restricted  l)y  the  cold  soil, 
the  temperature  of  which  may  be  only  40^  F.,  or  less,  down 
to  a  depth  of  4  feet.  Hence  the  little  plants  wilt  and  the 
needles  dry  up  and  die.  This  is  not  due,  as  in  dry  summers, 
to  the  absence  of  moisture  in  the  soil,  but  to  the  inability  of 
the  roots  to  absorb  water  in  the  cold  ground,  and  therefore  an 
abnormal  drying-up  of  the  needles  ensues. 

This  theory  will  not  explain  needle-cast  in  autumn,  when 
the  soil  is  warmer  than  the  air,  but  when  the  needles  are  cast 
in  the  spring,  it  is  in  comj^lete  accordance  with  the  observa- 
tions recorded  on  pp.  686 — 7,  under  the  headings  "  Locality  " 
and  "Weatlrer."  Sandy  soils  cool  down  at  night  to  lower  tem- 
peratures, under  similar  conditions,  than  clays,  and  wet  soils 
become  colder  than  dry  soils.  Insolation  is  greatest  on  bare 
southern  aspects. 

5.  Damacje  done. 

As  a  rule,  needle-cast  is  not  fatal  to  the  plants,  and  those 
which  have  been  attacked  may  recover,  provided  their  terminal 
buds  are  still  uninjured.  Naturally,  however,  the  injured  plants 
languish  for  some  time  and  are  very  liable  to  be  attacked  by 
insects.  If,  however,  the  disease  recurs,  and  the  terminal  buds 
of  the  plants  suffer,  they  have  no  chance  of  recovering. 

6.   Treatment. 

As  proper  treatment  of  the  disease  will  depend  on  its 
origin,  the  present  section  will  be  divided  into  headings 
according  as  the  disease  is  due  to  a  fungus,  frost  or  the  drying 
up  of  the  plants.  The  method  of  contending  with  the  attacks 
of  the  fungus  has  been  already  described  on  p.  465,  and  only 
the  two  latter  causes  will  be  dealt  with  here. 
a.  Frost. 

i.  Regenerate  Scots  pine  woods  under  a  shelterwood. 
Avoid  large  felling-areas  in  clearing  Scots    pine  woods,  and 


NEEULE-CAST.  691 

wherever,  owing  to  circumstances,  natural  regeneration  is 
impracticable,  narrow  strip-fellings  should  be  effected,  in 
order  to  afford  the  young  plants  lateral  shelter  against 
the  sun. 

ii.  Avoid  sowings,  and  especially  broadcast  sowings,  in 
artificial  reproduction  of  Scots  pine.  When  transplants  are 
scarce  it  is  preferable  to  sow  early  in  the  year,  in  drills  10  to 
12  inches  apart.  Densely  growing  seedlings  should  be  thinned, 
and  a  mixture  of  spruce  with  Scots  pine-seeds  acts  favourably, 
the  spruce  protecting  the  pines. 

iii.  Yearling  pines  are  best  planted  out  with  balls  of  earthy 
by  means  of  Heyer's  circular  spade,  so  that  all  injuries  to  the 
roots  are  avoided. 

iv.  Sowings  of  Scots  pine  should  be  abandoned  in  narrow 
deep  valleys  and  in  depressions. 

v.  As  regards  forest-nurseries,  the  following  rules  hold 
good : — 

(a)  The  nursery  should  be  in  an  exposed  situation  and  not 
too  small  in  area.  It  should,  if  possible,  be  higher  than  the 
surrounding  land,  never  in  a  depression,  or  nearer  than  50 
yards  to  a  wood  to  the  west. 

A  wood  to  the  west  of  the  nursery  reflects  the  rays  of  the 
sun  on  to  it,  which,  heating  the  soil,  cause  early  germination 
and  shooting  of  the  plants.  This  also  favours  stagnation  of 
the  air  and  late  frost. 

{b)  Beds  of  seedlings  should  be  covered  with  dead  leaves  or 
moss,  leaving  only  the  tops  of  the  plants  free. 

((•)  The  beds  may  be  protected  by  coverings,  which  sliould 
not  be  too  dense.  They  should  be  placed  at  about  a  yard 
from  the  ground,  towards  the  end  of  September,  and  before 
the  first  early  frosts,  and  may  be  removed  as  soon  as  late  frosts 
in  spring- are  no  longer  to  be  feared.  Throughout  the  winter, 
the  coverings  may  be  partially  removed  during  bright  days, 
but  should  be  replaceTl  before  sunset.  If  the  coverings  are 
placed  lower  down,  the  plants  suffer  from  insufficient  aeration, 
but  coverings  such  as  are  here  described  have  proved  very 
efficacious  in  different  parts  of  North  Germany. 

((/)  Seedlings  may  be  sprinkled  with  fine  dry  soil  at  the 
beginning    of    September,    so  that  only  the  needles  remain 

Y    Y    2 


692  PROTECTION   AOAINST    DISEASES. 

uncovered.  In  case  the  earth  should  be  washed  away  by  rain, 
it  must  be  replaced. 

(c)  Nursery-beds  should  be  manured  with  decomposed 
beech  leaf-mould.  This  has  been  strongly  recommended  by 
several  foresters,  and  a  coating  of  about  1  to  1^  inches  appears 
to  be  sutiicient.  This  prevents  sudden  wide  ranges  of  tem- 
perature in  the  surface  soil,  though  it  is  not  clear  on  this 
account  why  beech  leaf-mould  is  preferable  to  other  similar 
manure.  It  is  stated,  however,  that  heather-humus  when  used 
instead  of  beech  leaf-mould  does  not  prevent  needle-cast. 

(/)  When  2-year-old  plants  are  used,  the  yearlings  should  be 
lined  out  in  nursery-lines. 

b.  Dry  Needle-cast. 

The  principles  to  be  followed  in  the  case  of  this  variety  of 
the  disease  should  consist  in  plans  for  raising  the  temperature 
of  the  soil,  and  reducing  the  intensity  of  the  light,  in  order  to 
increase  the  activity  of  the  roots  and  reduce  transpiration. 
Attempts  should  also  be  made  to  increase  the  powers  of 
resistance  of  the  plants. 

Soil-temjyerature  is  increased  by  the  following  measures  : — 

i.  Draining  wet  soils. 

ii.  Deep  cultivation  and  manuring,  for  instance  with  burned 
turf,  but  these  measures  can  be  undertaken  only  in  permanent 
nurseries. 

iii.  Raising  the  level  of  the  soil  about  1  foot  in  places  pre- 
pared for  sowing  or  planting.  This  method  is  useful  for  other 
reasons,  and  especially  in  the  case  of  compact  or  wet  soils. 

iv.  Covering  the  intervals  between  rows  of  plants  in  the  beds 
with  substances  that  are  bad  conductors  of  heat,  such  as 
moss,  dead  leaves,  etc. 

Intensity  of  light  is  reduced  as  follows  : — 

v.  Reproduction  of  Scots  pine  under  shelterwoods,  or  with 
lateral  shelter. 

vi.  Sowing  Scots  pine  with  leguminous  fodder-crops,  such 
as  lucerne  or  saintfoin.  This  has  given  splendid  results  in 
Brandenburg  and  Mecklenburg. 

vii.  The  hardiness  of  the  plants  is  increased  by  giving  them 
plenty  of  space  from  the  first,   by  carefully  preserving  the 


NEEDLE-CAST.  693 

fibrous  rootlets  during  transplanting,  and  by  using  transplants 
with  balls  of  earth  round  their  roots. 

7.  Conclusion. 

From  the  above,  it  is  evident  that  the  two  varieties  of  the 
needle-cast  disease  may  be  treated  similarly.  Needle-cast, 
owing  to  the  fungus,  would  indeed  be  favoured  by  some  of  the 
rules  given  under  (a)  and  {h) ;  for  instance,  reproduction  under 
shelter,  and  manuring  and  covering  with  Scots  pine-branches. 

Two  other  methods  of  protection  have  recently  been  sug- 
gested, but  Hess  has  no  experience  of  his  own  regarding  their 
efficacy.     They  are  as  follows  : — 

i.  One  or  2-year-old  plants  may  be  carefully  dug  up  at 
the  end  of  September  or  beginning  of  October,  when  they 
have  assumed  their  normal  winter  colour,  and  placed  in  rows 
in  a  bed  of  loose  earth  raised  27  to  30  inches  from  the  ground, 
and  then  covered  loosely  with  a  few  dead  leaves.  The  plants 
will  be  green  and  in, good  order  for  planting  in  the  spring, 
when  other  plants  left  in  the  nursery-beds  have  become 
quite  red. 

ii.  According  to  the  other  method,  trenches  are  dug  24  to 
27  inches  broad,  and  30  to  40  inches  deep,  and  the  plants 
placed  in  rows  at  the  bottom  of  the  trench  with  earth  between 
the  rows,  either  in  autumn  or  in  early  spring.  Sticks  are 
placed  across  the  top  of  the  trench  at  distances  of  6  to  8 
inches,  which  are  then  covered  with  branches  of  Scots  pine,  or 
of  silver-fir.  Spruce  branches  will  not  do,  as  the  needles  drop 
off  too  readily.  The  density  of  the  covering  must  be  regulated 
according  to  the  state  of  the  weather,  and  it  should  be  denser 
when  there  is  a  considerable  range  of  temperature  between 
the  day  and  night  in  the  spring.  In  case  of  prolonged  drought 
the  plants  should  be  lightly  sprinkled  with  water. 

This  method  has  been  followed  with  advantage  in  certain 
forest  ranges  in  Prussia.  A  Irench  10  feet  long  will  contain 
about  5,000  1  to  2-year-old  pine-seedlings.  It  has  not, 
however,  always  proved  successful,  and  it  is  doubtful  whether 
trenching  plants  in  autumn  may  not  be  prejudicial.  More 
experience  is  necessary  before  it  can  be  confidently 
recommended. 


694 


PROTECTION   AGAINST    DISEASES. 


695 


CHAPTER    VI. 

DAMAGE  TO  TREES  BY  ACID   FUMES  FROM 
FURNACES,  etc. 

1.  Description  of  Injury  * 

Woods  long  exposed  to  acid  fumes  from  iron- smelting 
furnaces,  alkali  and  other  chemical  works  and  brickfields,  or  to 
excessive  coal-smoke  in  crowded  cities,  become  continually 
more  and  more  sickly,  and  may  eventually  die. 

The  needles  of  coniferous  trees  become  discoloured  at  first  on 
the  side  from  which  the  fumes  come,  turning  yellowish,  then 
reddish,  and  finally  falling  off,  probably  owing  to  the  action  of 
the  acids  on  the  chlorophyll.  The  buds  at  first  escape  injury, 
but  the  twigs  of  the  trees  gradually  die  from  the  summit  of  the 
trees  downwards.  In  this  way  the  crowns  of  the  trees  get 
continually  thinner,  as  if  they  had  been  attacked  by  the  pine 
beetle,  and  they  eventually  die. 

Broadleaved  trees  suffer  in  a  similar  way,  the  damage  to  the 
leaves  showing  itself  by  larger  or  smaller  reddish  blotches, 
which  gradually  spread  over  the  leaf  till  it  dies  and  falls  off 
the  tree.  The  fact  that  most  broadleaved  trees  are  leafless 
during  winter,  when  there  is  most  smoke,  accounts  for  their 
comparative  immunity  in  London,  whilst  in  Lancashire  large 
coal-fires  go  on  burning  all  the  year  round.  Then,  in  propor- 
tion to  the  area,  there  is  ten  times  as  much  coal  burned  at 
St.  Helen's  as  in  London,  and  consequently  vegetation  suffers 
much  more  in  the  former  place. 

••  Vide  "  Journal  of  the  Society  of  Chemical  Industry,"  pp.  202—206  and  pp.  342 
— 34.5.  Lunge's  "  Manufacture  of  Sulphuric  Acid  Alkali,"  vol.  i.,  p.  110  ;  vol.  ii., 
pp.  182—190.  "Air  and  Rain,"  by  Dr.  R.  Angus  Smith,  1872.  Hasenclever, 
"Chemische  Industrie,"  1879.  Von  Schriider,  Dr.  Julius,  and  Reuss,  Carl, 
"  Beschadigung  der  Vegetation  durch  Rauch  und  die  Oberharzcr  Hiittenranch- 
schaden."  Berlin,  1883.  The  best  monograph  on  the  subject. — Journal  of  Royal 
Hort.  Soc.,  March,  1891,  "Trees  and  Shrubs  for  Large  Towns,"  Maxwell  T. 
Masters  ;  also  '•  Effects  of  Urban  Fog  on  Cultivated  Plauts,"  F.  W.  Oliver, 


696  PROTECTION    AGAINST    DISEASES. 

Fruit-trees  exposed  to  acid  fumes  cease  bearing  fruit  before 
the  foliage  is  seriously  injured,  and  St.  Helen's  was  formerly 
famed  for  its  fruit;  but  since  1867,  owing  to  the  chemical 
works  in  its  neighbourhood,  no  fruit  has  been  produced  there. 
Crops  of  wheat  exposed  to  acid  fumes  may  to  all  appearance 
be  ripe  and  full  when  scarcely  a  grain  is  to  be  found  in  the 
ears.  Eoot-crops,  such  as  potatoes  and  turnips,  suffer  less, 
and  on  the  whole  trees  suffer  much  more  than  grass  or 
agricultural  crops. 

In  the  Tavistock  woods,  large  areas  of  oak  coppice  were 
seriously  injured  by  sulphurous  fumes  from  arsenic  mining 
works.  Owing  to  the  diminished  working  of  these  mines,  it 
is  now  possible  to  replant  the  injured  area  with  oak  and 
larch. 

In  1861,  extensive  damage  was  found  to  have  been  done  to 
coniferous  woods  by  the  fumes  from  the  works  at  Freiburg,  in 
Saxony,  in  some  of  which  sulphuric  acid  is  made  from  iron 
pyrites.  Stockhardt*  and  Schroder,!  at  the  Tharandt 
laboratory,  investigated  the  chemical  components  of  the 
smoke  which  cause  the  damage,  and  Hamburger  |  has  done 
the  same  more  recently.  Subsequent  notices^  have  appeared 
about  damage  in  the  Oberharz  owing  to  acid  fumes,  and  the 
area  of  forest  damaged  by  three  iron- works,  in  1881,  was 
about  11,250  acres.  In  the  Altenau  forest-range  this  damage 
has  become  noticeable  since  American  ores  have  been  smelted, 
which  contain  more  sulphur  than  the  native  ores. 

Even  by  smoke  from  charcoal  kilns  Scots  pine  needles 
have  been  reddened  at  a  distance  of  50  yards,  but  this  is  due 
to  the  heat  of  the  smoke. 

2.  Injurious  Components  of  Smoke. 

It  has  been  proved  by  observations  made  at  Tharandt,  that, 
of  the  components  of  the  fumes  from  the  Saxon  Works,  lead, 
arsenic,  and  sulphur  compounds,  soot,  etc.,  only  sulphur 
dioxide  is  hurtful  to  woody  growth,  and  a  similar  result  has 

*  "  Tharaiidter  Jliibch.,"  vol.  ix.,  1853,  p.  109;  also  vol.  xxi.,  1871,  p.  218. 
+  Id.,  vol,  xxii.,  p.  18r>  ;  vol.  xxiii.,  p.  217. 
X  Id.,  1888,  p.  144 

§  llcuss,"  Ztschrft.fr.  Frst.  u.  .Tgdwsn. ,  1881,"  p.  Cm.  Also'- Cntilhltt,  fr.d.  ges 
Frstw.,"  1881,  p.  2G7  ;  id.,  1882,  p.  443. 


DAMAGE    TO    TREES    BY    ACID    FUMES.  697 

been  arrived  at  in  the  case  of  coal-smoke.  In  order  to 
ascertain  the  fact,  various  species  of  wood}^  plants  have  been 
subjected  to  frequent  and  prolonged  exposure  to  artificially 
produced  fumes  of  each  of  the  separate  components  of  the 
smoke.  Sulphm-  dioxide  in  the  soil  has  no  prejudicial  effects 
on  plants,  as  has  been  proved  by  watering  them  with  diluted 
sulj)hur  dioxide  solution,  for  the  gas  speedily  becomes  converted 
into  sulphuric  acid,  and  forms  harmless  compounds  with 
alkalies  in  the  soil. 

The  action  of  the  sulphur  dioxide  when  the  air  is  moist,  or 
the  leaves  moistened  with  dew  or  rain,  is  rapid  and  decisive  ; 
it  is  probably  absorbed  by  plants  in  the  form  of  sulphuric 
acid,  being  taken  up  in  variable  quantities  by  the  leaves  or 
needles  of  different  species  of  trees.  It  then  proceeds  from 
the  leaves  into  the  twigs.  The  leaves  or  needles  gradually 
turn  brown,  owing  to  the  decomposition  of  the  chlorophyll 
and  tissues  of  the  leaf. 

Sulphur  dioxide  finds  its  way  into  the  atmosphere  by  the 
roasting  of  minerals  containing  sulphur,  and  from  coal-fires, 
coal  containing  about  2  per  cent,  of  sulphur,  chiefly  in  the 
form  of  iron-pyrites.  What  minute  quantities  of  this  gas 
suffice  to  kill  plants  was  proved  in  1864  by  experiments  with 
spruce  plants  which  were  exposed  to  air  containing  only  one- 
millionth  part  of  sulphur  dioxide.  After  335  puffs  of  the  air, 
the  points  of  the  needles  began  to  turn  brown,  and  eventually 
turned  completely  brown. 

It  has  also  been  supposed  that  the  soot  in  smoke  might 
injure  forest  trees  by  blocking  up  their  stomata,  but  this 
mode  of  injury  is  not  admitted  by  Stockhardt. 

As  injurious  compounds  of  the  smoke  of  other  works  maybe 
reckoned :  vapours  of  mercury,*  hydrochloric  acid  gas,  oxides 
of  nitrogen,  and  chlorine,  also  steam  containing  soda  particles 
from  cellulose-factories.  The  influence  of  hydrochloric  acid 
from  alkali-works  is  shown  whenever  the  air  contains  0"! 
per  cent,  by  a  considerable  increase  in  the  chlorine  in  the 
leaves.  Leaves  get  brown  or  red  edges,  and  eventually  dry-up 
and  fall.  Chlorine  acts  similarly,  but  more  energetically. 
Hydrochloric  acid  is  very  destructive  to  vegetation,  sometimes 

•  Wagner's  "  Jhrbcli.,"  1874,  p.  277. 


698 


PROTECTION    AGAINST    DISEASES. 


forming  dense  clouds  which,  after  escaping  from  alkali- works, 
settle  on  fields  and  kill  whole  patches  of  the  crops  in  them ; 
it  is,  however,  on  the  whole  less  hurtful  to  woods  and  crops 
on  a  large  scale  than  sulphur  dioxide,  and  the  same  may  be 
said  of  the  similar  action  of  the  oxides  of  nitrogen,  and 
chlorine.  Dr.  Angus  Smith  gives  the  following  comparative 
statement  of  acidity  of  air  at  different  places  in  England  : — 


Locality. 

HCl. 

SO2 

Remarks. 

Blackpool,  on  the  Lancashire  coast 

London  

Manchester 

St.  Helen's 

Underground  Railway,  London 

100 
320 
396 
516 
974 

100 
282 
410 
387 
1243 

Dr.    Smith 
gave  the  pro- 
portions     in 
SO,-„and  fths 
of   these    are 
g:iven  here  as 
SO2. 

In  a  field  near  Blackpool  he  found  20"27  grains  of  hydro- 
chloric acid  and  155'30  grains  of  sulphur  dioxide  in  1,000,000 
cubic  feet  of  air,  and  the  quantities  in  the  other  places  may 
be  calculated  from  these  figures. 

Dr.  Hamburger*  states  that  he  exposed  leaves  to  the  action  of 

11,      ,  ,  .   and  ;r-^:zr-,  oi  sulphuric  and  hydrochloric 

10     100     1,000  2,000  ^  ^ 

acids  of  equivalent  strength,  n  being  a  normal  solution  of 

49  grammes  of  sulphuric  acid,  or  36  J  grammes  of  hydrochloric 

acid  in  one  litre  of  water. 

The  normal  solution  produced  discoloration  in  about  half  an 

hour,  yellowish-brown  spots  appearing  in  the  middle  of  the  leaves 

and  extending  gradually  over  the  whole  surface.     The  —  took 

3   hours    before    signs    of    destruction    appeared.     The 
acted  in  about  a  day,  but  the  action  of  the  sulphuric  acid  was 
stronger  than  that  of  hydrochloric  acid.     The  ^—-sulphuric 

acid  produced  discoloration  in  about  a  week,  while  the 
hydrochloric  acid  required  10  days  to  do  so. 

*  "Journal  of  the  .Society  of  Chemical  Industry,''  1884,  p.  205, 


100 


DAMAGE    TO   TREES   BY   ACID    FUMES.  699 

The     ^     acid,  equivalent  to  24^  grammes  of  sulphuric  acid 

or  18^  grammes  of  hj-drochloric  acid  in  1,000,000  parts  of 
water,  seemed  to  have  no  action.    Two  greenhouse  plants  were 

submitted  to  a  daily  spra}'  of  the  ^fT^f^  ^^id  for  a  month,  hut 

showed  no  corrosion. 

3.  Damage  done. 

a.  General  Account. 

Among  the  direct  kinds  of  damage  done  by  acid  fumes  to 
trees  are  : — loss  of  increment,  thinning  out  of  woods  and 
formation  of  blanks,  injury  to  fruit,  especially  in  the  case  of 
orchard-trees,  loss  of  fodder  by  destruction  of  grass  in  a 
forest.  Damage  is  done  indirectly  by  rendering  the  woods 
liable  to  insect-attacks,  to  fire  and  other  dangers. 

h.  According  to  Species. 

Conifers  suffer  more  than  broadleaved  species  from  smoke, 
even  although  the  needles  under  similar  conditions  absorb 
less  sulphur  dioxide  and  are  in  themselves  less  sensitive 
and  hardier  than  other  leaves.  This  is  due  to  the  longer 
duration  of  the  needles  and  their  consequently  increased 
exposure  to  the  bad  influence  of  the  gas,  and  to  the  greater 
powers  of  recovery  possessed  by  broadleaved  species. 

Thus  evergreen  conifers  are  not  only  longer  exposed  each 
year,  but  the  evil  accumulates  from  year  to  year  as  long  as 
the  needles  remain  on  the  tree,  whilst  broadleaved  trees 
annually  throw  off  their  leaves. 

Schroder*  found  that  1,000  square  centimeters  of  leaf- 
surface,  containing  double  that  quantity  above  and  below, 
■will,  within  36  hours,  absorb  sulphuric  dioxide  as 
follows : — 

C.  cm. 

Silver-fir  needles,  young 1-8 

„         old 1-4 

Alder  leaves •   7*9        . 

.      •  "  Thar.  Frstl.  Jhrbch.,'  vul.  xxii.,  1872,  p.  l'J3. 


700 


I'KOThX'TION    ArJAINST    DISEASES. 


Fig.  298. — Oaks  uear  a  manufacturing  town,  the  foliage  damaged  h\  acid  fumes, 
photographed  August,  1882.* 


Fig.  299.— Same  oaks' photographed  July,  1888,  several  years'  cumulative  injury 
having  killed  the  trees.* 

*  From  Crooiiian  Lecture  by  Marshall  Wartl  (_ri(Ir  p.  (J?!), 


DAMAGE    TO    TREES    BY    ACID    FUMES  701 

When  exposed  a  second  time  for  20  hours,  the  silver-fir 
needles  absorbed  1*6  c.  cm.,  beech  leaves  3'1  c.  cm. 

Webster*  gives  a  list  of  trees  and  shrubs  suitable  for  town- 
planting,  but  among  conifers  only  mentions  the  deciduous 
Ginhfjo  hiloha,  or  maidenhair  tree,  as  flourishing  in  the  worst 
smoke-infected  parts  of  London,  and  Retinospora  jdumosa 
aurea,  which  has  stood  for  seven  years  in  one  of  the  most 
smoky  districts  of  Glasgow,  and  looks  almost  as  well  as  when 
brought  from  the  country. 

Masters  also  recommends  Ginkgo  hiloha,  and  Finns  excelsa. 

J.  W.  Sowerby,  the  Secretary  to  the  Royal  Botanic  Society 
of  London,  who  has  resided  in  the  Botanic  Gardens,  Piegent's 
Park,  since  1842,  states  that  when  the  gardens  were  first  laid 
out  (1839-45)  special  mounds  were  made  and  planted  w^ith 
nearly  all  hardy  species  of  conifers,  and  although  the  natural 
soil  of  the  gardens  is  a  stiff  yellow  clay,  suitable  soil  was 
furnished  for  the"  different  trees;  but  in  1895,  only  a  few 
miserable  plants  remained,  including  five  or  six  deodars, 
and  some  yews,  which  last  longest,  but  were  then  looking 
very  bad. 

The  amount  of  damage  done  to  broadleaved  trees  depends 
not  only  on  the  susceptibility  of  the  leaves,  but  also  on  the 
powers  of  recovery  of  each  species,  so  that  trees  which  unite 
least  susceptibility  to  greatest  powers  of  recovery  will  suffer 
least. 

Schroder  has  drawn  up  the  following  list : — 

1.  Conifers  :  Silver-fir,  spruce,  Scots  pine  least  susceptible. 

2.  Broadleaved  plants :  Beech,  lime,  poplars,  alder,  maples, 
ash,  hornbeam,  aspen,  oak. 

The  immunity  of  oak  is  not,  however,  confirmed  by  English 
experience,  and  Marshall  Ward  states  that  oaks  suffer  greatly 
from  acid  fumes.  Perhaps  the  German  authorities  refer  to 
sessile  oak,  which  is  rare  in  England,  where  the  pedunculate 
oak  abounds. 

A   Belgian!    official   report   also   considers   the  hornbeam 

•  "  Practical  Forestry,"  by  Angus  D.  Webster.  Rider  k  Son.  2n(l  etlition. 
London,  18!).5. 

t  "Rapport  par  la  Commission  d'Enquete  relative  a  I'influencedes  Emanations 
Acides  sur  la  Vegetation,"  quoted  by  Dr.  Angus  Smith  in  an  appendix  to  "  Air 
and  Rain." 


702  PROTECTION    AGAINST    DISEASES. 

and  oak  as  suffering  most  of  all  broadleaved  species  from 
acid  fumes  and  even  places  them  al)ove  the  larch  in  this 
respect. 

Borggreve  at  Miinden  drew  up  a  similar  table  to  that  of 
Schroder,  in  the  following  order : — 

1.  Silver-fir,  spruce,  Scots  pine. 

2.  Beech,  lime,  poplar,  alder,  maples,  and  ash. 

3.  Hornbeam,  aspen. 

4.  Oak  (least  susceptible). 

According  to  Hess's*  own  experiments  elms  (Ulmus  mon- 
tana  and  campcstris)  must  be  reckoned  among  resisting  species. 

The  above  grouping  cannot  alwaj^s  be  relied  on,  as  there 
are  too  many  modifying  factors  in  particular  cases,  London, 
with  its  constant  coal-smoke  and  numerous  factories  and 
frequent  dense  sulphurous  fogs,  should  give  better  practical 
results  as  to  the  comparative  powers  of  resistance  of  trees 
than  any  merely  artificial  laboratory  experiments. 

There  are  line  large  flourishing  plane-trees  {Platanus 
orientaUs,]  L.)  in  Cheapside  and  on  Ludgate  Hill,  which  are 
entirely  surrounded  by  tall  buildings,  and  the  plane  is 
growing  ^Yell  on  the  Thames  Embankment  and  in  many  parts 
of  London.  The  plane-tree  sheds  large  flakes  of  its  bark 
annually,  and  its  buds  are  sheltered  by  its  sheathing  petioles ; 
these  facts  probably  contribute  to  its  immunity. 

The  following  account  of  the  trees  and  shrubs  which  flourish 
in  the  Botanic  Garden  in  Regent's  Park,  London,  has  been 
kindly  supplied  by  J.  W.  Sowerby. 

"  Of  the  plane  there  are  many  very  large  trees.  Maples 
of  several  species  and  varieties.  Horse-chestnuts  flower 
and  fruit  as  well  as  in  the  country.  Poplars  of  many 
species,  t  Elms,  of  which  a  belt  surrounds  the  gardens, 
and  one  old  elm  which  was  on  the  ground  in  1838  is  still 
healthy. 

•  "Frstl.  lilttr.,"  1874,  p.  31. 

t  Masters  and  Webster  rccommeml  for  town  planting  P.  orientalu  acerifolia, 
which  has  less  deeply  divided  leaves  than  the  normal  plant,  and  may  be  dis- 
tinguished from  P.  orculentnliH,  L.,  by  the  many  fruit-balls  attached  to  its 
peduncles. 

X  Populiix  riinadeitsLt,  L)esf.,  has  a  reputation  in  theBlack  Country  for  immunity 
from  the  effects  of  fumes.    P.  halmmlfera,  L.,  is  growing  well  in  St.  James'  Park. 


DAMAGE    TO    TREES    BY    ACID    FUMES.  703 

"  Lime  withstands  smoke,  but  suffers  from  green  aphis  and 
otlier  pests,  and  looks  shabby  in  esLvly  autumn,  as  the  leaves 
fall  early.  Eobinia  thrives  for  30 — 40  years,  but  then  dies 
gradually,  perhaps  owing  to  the  cold  clay  soil  of  the  gardens. 
Two  oaks  remain  small  and  scarcely  grow,  but  have  kept  alive 
for  over  50  years.  Laburnum  does  well,  and  so  do  white 
and  red  thorns. 

"Of  shrubs,  Aucuha  japonka  is^  best,  and  fruits  freely,  and 
so  do  several  varieties  of  privet.  Lilacs  and  box  do  well,  and 
Mahonias  fairly." 

Webster  adds  the  following  to  this  list :  species  of  lihus 
and  Cotoneaster,  Virginia-creeper,  ivy  and  the  vine,  besides 
Daphne  Laureola,  L.,  Skimmea  japonica,  liihes  sanguineus,  and 
Jasminum  nudijioruni.  He  also  gives  a  list  of  trees  suitable 
for  town-planting,  that  generally  agrees  with  Sowerby's  list, 
but  also  contains  the  following:  Ailanthus  glandulosa,  DesL, 
Magnolia  acuminata,  L.,  Liriodendron  tulipifera,  L.,  Catalpa 
speciosa,  Engelm,  Morus  nigra,  L.  He  states,  however,  that 
horse-chestnuts,  limes,  and  elms  soon  show  signs  of  distress 
when  grown  in  smoky  localities. 

According  to  the  Belgian  official  report,  the  black  alder 
{Alnus  glutinosa,  Gaertn.)  may  be  seen  growing  close  to 
chemical  works,  and  in  situations  very  much  exposed  to  acid 
fumes,  but  apparently  suffering  very  little  from  them. 

In  planting  avenues,  or  parks,  in  a  crowded  city,  however, 
not  only  immunity  from  fumes  has  to  be  considered,  but  also 
the  nature  of  the  soil,  the  desirability  of  the  tree,  and  the 
amount  of  shade  it  gives,  and  whether  it  bears  radiation  of 
heat  from  the  houses  and  streets.  The  poplar,  having  a 
straggling  crown  and  its  branches  being  very  brittle,  is  not 
suitable,  wliile  limes,  except  Tilia  licteroplujlla,  Vent.,  are 
liable  to  lose  their  foliage  prematurely  in  hot  dry  summers. 
Probably  the  plane  and  sycamore  are  the  best  trees  for  the 
purpose.  Of  oaks,  probably  the  Turkey  oak  {Qucrcus  Cerris, 
L.)  is  the  only  deciduous  species  which  can  at  all  resist  the 
smoke  of  a  large  city.  Quercus  Ilex  is  termed  by  Masters 
a  good  town  tree. 

In  the  Black  Country,  near  Wolverhampton,  Dudley  and 
Bilston,  the  air    is  at  present  not  nearly  so  impure  as  was 


704  J'ROTECTIOX   AGAINST    DISEASES. 

formerly  tlie  case  when  the  shafts  of  the  smelting  furnaces 
were  open,  and  the  furnaces  themselves  much  more  numerous 
than  at  present.  Dudley  Park  is  exposed  on  the  east  to  the 
acid  fumes  of  smelting  furnaces,  and  yet  ash,  poplar,  and 
sjxamore  trees  are  growing  there  fairly  well  with  elder, 
hawthorn  and  hazel  undergrowth,  while  beech  appears  on  the 
western  slopes  of  the  park,  that  are  exposed  to  open 
country  where  there  are  ^lo  furnaces.  Grass  grows  well 
enough  in  the  Black  Country,  and  there  can  he  no  reason 
why  the  large  extent  of  uneven  grassy  land  near  Bilston 
(about  14,000  acres),  where  the  coalfields  have  been  worked 
out,  the  soil  being  weathered  shale,  should  not  be  planted 
with  trees,  instead  of  remaining,  as  it  is  at  present,  a  dreary 
waste.  It  is  said  that  to  level  this  land  would  cost  £100  per 
acre,  but  no  levelling  would  be  necessary,  if  it  were  to  be 
planted  up  with  trees,  which  grow  well  enough  on  similar 
land  in  Belgium. 

There  are  works  at  Bilston  for  galvanising  iron,  and  the 
molten  zinc  in  which  the  sheets  of  iron  are  plunged  is  covered 
with  chloride  of  ammonium  to  jjrevent  its  oxidising.  The 
fumes  given  off  during  the  process  are  said  to  kill  all  leaves  of. 
trees  near  the  works  by  June  every  year,  but  these  fun)es 
probably  extend  only  for  a  short  distance  from  the  works. 

Since  1903  planting  has  been  undertaken  in  the  Black 
Country  under  the  auspices  of  the  Midland  Eeafforesting 
Association.     (Vide  Figs.  297,  298). 

r.  Age  of  Trees. 

"Woods  suffer  from  acid  fumes  at  all  ages,  but  poles  15 — 30 
years  old  appear  to  suffer  most. 

(I.  Locality. 

The  influence  of  the  locality  makes  itself  felt  chiefly  by  the 
direction  of  the  prevailing  winds  which  bring  the  fumes 
towards  the  trees. 

The  Belgian  Commission  mentions  2,000  meters  as  the 
greatest  distance  from  chemical  works,  in  the  direction  of  the 
prevailing  winds,  at  which  damage  was  observed.  In  certain 
cases,  however,  woods    have    been    injured    at    distances   of 


DAMAGE   TO   TREES    BY    ACID   FUMES.  705 

4 J  miles  from  the  works,  but  naturally  the  amount  of  injury 
done  varies  inversely  with  the  distance.  Trees  bordering  on 
the  wood,  and  especially  on  woods  to  the  east  and  north-east 
of  the  works,  will  suffer  most.  In  narrow  valleys  even  the 
smoke  of  locomotives  has  proved  prejudicial  to  trees  on  either 
side  of  a  railway.  Oliver  states  that  the  effects  of  London 
fog  extend  to  35  miles  westward,  and  that  seedlings  of  Cncnr- 
hitaceae  and  tomatoes  are  thus  killed  at  even  that  distance 
from  London. 

It  has  been  observed,  chiefly  in  the  Oberharz,  that  woods 
growing  on  fertile  soil  resist  acid  fumes  better  than  those  on 
poor  soils. 

e.  Climate. 

Exposure  to  light  and  moisture  are  not  without  influence  on 
the  action  of  acid  fumes.  Leaves  suffer  more  when  dew  is 
resting  on  them  than  when  they  are  dry.  Thus  the  damage 
will  be  at  its  maximum  after  rain  at  midday,  and  at  its 
minimum  with  cool  nights  and  dry  days.  The  damage  during 
rainy  weather,  though  more  severe  than  in  dry  weather,  does 
not  extend  far  from  the  works,  as  the  rain  speedily  dissolves 
'the  fumes. 

/.  Suiulnj  f'irn/nisfanrcs. 

When  older  woods  overshade  an  underwood,  the  former  may 
protect  the  latter  from  damage  by  fumes,  and  trees  standing 
above  the  general  leaf-canopy  of  the  wood,  such  as  standards 
in  high  forest  or  above  coppice,  suffer  most.  The  shelter 
afforded  to  crops  and  orchards  by  walls  and  hedges  is  also 
considerable. 

Damage  is  not  so  soon  marked  in  young  woods  under  30 
years  old  as  in  older  woods.  In  old  woods,  especially  coni- 
ferous, damage  is  soon  recognisable.  Their  foliage  soon 
becomes  thinner  ;  the  shoots  dry  up,  and  death  soon  occurs, 
often  in  two  or  three  years. 

4.  Metliods  oj  Rrcnfinising  Damage. 

The  question  regarding  external  or  internal  signs  for  recog- 
nising damage  by  fumes  is  of  great  scientific  interest.  It  is 
also  of  practical  importance,  as  in  the  disputes  or  lawsuits 
between  owners  of  woodlands  and  of  smelting  furnaces,  the 

P.P.  z  z 


700  PROTECTION    AOAIXST    BISKASES. 

first  ground  for  determination  is  whether  the  damage  to 
exposed  woods  is  caused  solely  by  the  fumes  or  is  due  to  other 
causes  (frost,  heat,  dry  winds,  infection,  or  fungi). 

Tiiere  are  only  two  methods  for  determining  the  cause  of 
the  damage : — 

(a)  Chemical  analysis  of  the  injured  tree-parts  (leaves, 
flowers,  etc.). 

(h)  Microscopic  examination  of  the  marks  on  the  injured 
needles  or  leaves. 

On  this  subject  there  has  been  since  1895  a  keen  literary 
dispute,  in  which  Borggreve,  Schroder,  Hartig,  Eamann,  Yater 
and  Wieler  have  contended.  Most  of  these  disputants  prefer 
chemical  analysis,  to  determine  the  amount  of  sulphuric  acid 
in  the  ashes  of  the  leaves.  This  must  obvio.usly  be  done  by 
a  chemical  expert.  The  excess  of  sulphuric  acid  in  affected 
leaves  over  the  amount  in  leaves  from  woods  unexposed  to 
fumes  decides  the  question.  As,  however,  the  quantity  of  SO3 
in  perfectly  healthy  leaves  varies  much,  Yater  considers  the 
following  conditions  necessary  to  prove  damage  by  fumes : — 

1.  All  injured  and  sound  trees  experimented  on  must  have 
been  growing  on  similar  soil  and  at  various  distances  from  the 
smelting  furnaces. 

2.  As  a  comparison,  the  average  quantity  of  SO3  in  sound 
trees  must  not  be  taken,  but  sound  trees  must  be  found  and 
the  quantity  in  them  measured. 

3.  A  sufficient  number  of  sample  trees  must  be  chosen  in 
order  that  reliable  results  may  be  obtained. 

Pi.  Hartig  prefers  the  microscopic  method,  at  any  rate  for 
spruce.  He  considers  the  foxy  red  colour  of  the  contents  and 
walls  of  the  cells  bounding  stomata,  and,  when  the  fumes  are 
very  strong,  the  red  colour  of  the  prosenchymatous  bundles, 
as  sufficient  proof  of  the  poisoning.  Such  needles  cannot 
assimilate  CO2.  They  remain  apparently  healthy  for  several 
years  on  the  trees,  and  die  when  the  woody  bundles  become 
affected. 

Piamann  and  Soraner  both  disagree  with  Hartig's  statement 
tliat  the  change  in  the  contents  of  the  cells  points  exclusively 
to  damage  by  fumes,  as  it  may  l)e  due  to  damage  by  other 
factoi-s. 


DAMAGE  TO  TREES  BY  ACID  FUMES.        707 

Hess  therefore  considers  the  chemical  analysis  as  the  best 
proof  of  damage  done  by  fumes. 

The  presence  of  sulphur  dioxide  in  the  air  near  the 
furnaces  is  also  an  important  factor  in  this  question,  and 
the  air  and  the  rain  and  snow  that  fall  through  it  should 
therefore  be  analysed. 

5.  Protective  Measures. 

No  thoroughly  efficient  measures  have  been  devised  against 
this  evil.  Tall  chimneys,  sometimes  500  feet  high,  carry 
the  fumes  into  the  higher  strata  of  the  atmosphere,  but  it 
has  been  found  that  hydrochloric  acid  descends  from  them  to 
the  ground  in  dense  clouds,  and  lays  waste  the  vegetation  at 
greater  distances  from  the  works  than  before. 

The  best  protective  measure  against  hydrochloric  acid  is 
to  get  it  condensed,  as  is  now  done  in  the  British  Isles  under 
the  Alkali  Acts  of  1863  and  1870,  so  that  less  than  1  per  cent, 
of  the  acid  generated  in  the  works  escapes  into  the  air. 

Tliere  is  more  difficulty  in  dealing  with  the  sulphur  dioxide, 
and  even  the  most  perfect  smoke-combustion  cannot  free  the 
air  of  it.  Attempts  have  been  made  in  Germany  to  convert  it 
into  sulphuric  acid,  but  this  removes  only  one- third  of  the 
injurious  gas,  and  at  Clausthal,  in  Germany,  1,250  tons  of 
sulphur  are  annually  sent  into  the  air,  greatly  damaging  the 
coniferous  woods  in  the  neighbourhood. 

The  forester  in  districts  where  hurtful  fumes  exist  can  there- 
fore act  only  by  planting  protective  belts  of  strong  transplants 
of  the  most  resisting  trees  in  the  direction  of  the  factories,  and 
managing  them  entirely  by  the  selection  system.  Under  the 
shelter  of  these  belts  it  will  be  better,  if  possible,  to  grow 
coppice  or  coppice-with-standards,  which  do  not  attain  the 
height  of  high  forest.  Conifers  should  not  be  grown  near 
smelting  furnaces. 

G.  Estimation  of  Damage. 

As  owners  of  woods  injured  by  factory  fumes  can  claim  com- 
pensation in  the  courts  of  law,  the  question  of  estimating 
the  damage  done  is  of  great  importance. 

In  18G4  the  Freiburg  works  hud  to  pay  i'2,750  compensation 


708  PROTECTION   AGAINST   DISEASES. 

for  damage  done  to  vegetation.  Estimates  of  the  value  of  the 
damage  must  be  made  in  accordance  with  the  principles  of 
forest  valuation,  and  involve  much  difficulty.  More  will  not 
be  said  on  this  subject  here,  but  references  are  given  below* 
to  German  books  specially  dealing  with  it. 

•  Kraft,  "  Ueber  die  Berechnung  der  durch  Hiittenrauch  veranlassten  Schadi- 
gung  von  Hokbesfiinden,"  "  Ztschift.  £r,  Frst.  u.  Jgdw.,"  1887,  p.  270  ;  lludnick, 
Id.,  1SH9,  p.  417. 


rig.  300.— Woodland  Gladu  near  Cradley,  in  tlie  lilack  Country. 
(Midland  Reafforesting  Association.) 


INDEX. 


Adders,  172 

Aecidium  Abietinum,  462 
,,  columnare,  462 
,,  Conoruin  Piceae,  472 

,,         elatinum,  448 
,,  strobilinum,  472 

Aglaospora  taleola,  481 

Animals,  injuries  by,  9o 

Ants,  190 

Aphididae,  ;3G1 

Ash-twig  moth,  3^4 

Atmospheric  influences,  489 

Avalanches,  61 G 

B. 
Bacteria,  4"J1 
Badger,  129,  1G7 
Bark,  utilisation  of,  27 

,,      rights  to,  84 
Bark-beotles,  148,  235,  434,  534,  C41 
Bark-blistor,  oak,  481 
,,  larch,  454 

Bark-scorching,  522 
Bears,  135 
Beavers,  135 
Beech  canker,  477 

,,      seedling  mildew,  482 

,,      woolly  aphis,  3G6 
lioes,  193 
Birch,  402 
Birds,  damage  by,  136 

,,      useful,  167 

,,      protection  by  law,  172 
Black-gafne,  138 
Blackthorn,  403 
Bordeaux  mixture,  4(56 
Bordered-white  moth,  326 
Botritis  Douglussii,  461 
Boundaries,  10 
Bracken,  407 
Brambles,  403 


Branchwood,  dead,  51 
Broom,  399 

C. 
Caeoma  piuitorquum,  444 
Camels,  40,  47 
Canker,  beech,  477 

,,        silver- fir,  449 
Capercailzie,  138 
Cattle,  40 
Centipedes,  173 
Cerambycidae,  148,  279 
Charcoal,  91 
Chci-mes,  361,  457 
Chrysomyxa  Abietis,  462 
Cinipidae,  358 
Chck-beetles,  214 
Cockchafers,  200 
Coccidae,  366 

Colbert's  Eefonu of  French  forests,  2 
Coleophora  laiiceUa,  346,  456 
Coleoptera,  injurious,  199 

useful,  180 
Communal  forests,  firewood,  (51 
Compiegne,  forest  of,  3,  107 
Coral-spot  disease,  479 
Corticium  amoi-phiun,  454,  471,  682 
Cossus,  14B,  282,  291 
Crickets,  368 
Crows,  130 
Cuckoo,  165 
Cuscuta,  417 

D. 
Dasyscypha  caljcina,  454 
Dean  forest,  2 

,,         ,,      plague  of  voles,  127 
Death  watch  beetle,  217  « 

Diptera,  useful,  194 

,,         injurious,  367 
Diseases  of  insects,  186, 302, 317, 322 

,,       of  plants,  671 
Dodder,  417 


10 


INDEX. 


Dormice,  122 
Dragonflics,  197 
Drainage,  601 
Drought,  514 


Easements,  forest,  67 
Elephants,  40,  47 
Elm  bark-beetle,  277 
Epping  forest,  89 
Exoascus,  448 
Exosporium,  455 

F. 
Factory  fumes,  695 
Fallow  fleer,  109 
FeiTets,  118 
Finches,  injurious,  140 
utility  of,  168 
Fires  in  forests,  638 
Fisheries,  53,  89 
Flies,  195 

Fomes  annosus,  435 
Foxes,  117,  130,  167 
Frost,  491 
Frostcrack,  505 
Frostlifting  of  seedlings,  510 
Fungi,  418,  421 

G. 
Gall-flies,  360 

,,  -wasps,  358 
Game,  53,  89 
Gastropacha  pini,  294 
Geometridae,  326 
Goat  moth,  148,  282,  291 
Goldcrests,  167,  244 
Grease  bands,  176,  300,  318,  331 
Greased  baiTiers,  176 
Gulls,   168 
Gypsey  moth,  319 

II. 
Hail,  557 
Hares,  40,  47,  115 
Ileatcrack,  526 
Heather,  400 
Hedgehog,  129,  167 


Hemiptera,  injurious,  361 

,,  useful,  197 

Herdsmen,  48 
Heron,  utility  of,  130 
Herpotrichia  nigra,  472 
Honey  fungus,  429 

,,    .    wild,  53 
Hydnum  diversidens,  476 
Hydrochloric  acid,  effect  on  trees, 

697 
Hylobius  abietis,  225 
Ilylurgus  piniperda,  265 
Hymenoptera,  injurious,  349 

useful,  1.S4 
Hypnum,  50,  408  * 
Hysterium  Pinastri,  465 

'l. 

Ichneumon  wasps,  173,  184,  2-14 
Insect  diseases,  186,  302,  317,  322 
Insects,  classification,  149 

,,        index  of  destructive,  374 

,,         injurious,  199 
useful,  180 
Insolation,  514 
Inundations,  586 

J. 
Jays,  139,  168 
Juniper,  409,  419 

K. 

Kestrel,  utility  of,  130,  168 

L. 

Ladybirds,  183 

Lapwing,   168 

Larch  blister,  348,  454 

,,      miner  moth,  346,  456 
Leaf-beetles,  283 
Leaf -roller  moths,  331 
Leaves,  utilisation  of,  29 

,,       rights  to,  84 

,,       injured  by  fumes,  695 
Lepidoptera,  288 
Lianes,  410 
Lightning,  658 
Litter,  utilisation  of,  49 


INDEX. 


71  I 


Litter,  rights  to,  88 
Locusts,  371 
Longicorn  beetles,  279 
Looper  moths,  326 
Lophodennium  macrosi^orum,  -107 
,,  nerviseq Ilium,  4G8 

Pinastri,  405,  6S8 
Loranthus,  415 

M. 
Martens,  117,  122 
Melamporella    caryophyllacearum , 

448 
Melampsora  Ilartigii,  485 

pinitorqua,  444 

sp.,  48G 
Mice,  123 

Minor  produce,  27,  53 
Mistletoe,  4 1 2 
Mole,  129 
Mole-cricket,  308 
Mouse  typhus,  134 
Musk  beetle,  283 

N. 

Nectria  cinnabarina,  479 
,,  Cucurbitula,  452 
,,       ditissima,  477 

Needle-cast,  larch,  469 

,,  pine,  4G5,  685 

,,  silver-fir,  468 

,,  spruce,  467 

Needle  fungi,  461 

Nesting  boxes  for  birds,  169 

Neuroptera,  use  fill,  195,  199 

New  Forest,  2 

Noctuidae,  319 

Nun  moth,  310 

Nurseries,  protection  of,  396 


Oak  bark-blister,  481 

,,    leaf-roller  moth,  333 
Occlusion  of  wounds,  104 
Offences  in  forests,  oo 
Orchestes  fagi,  221 
Orthoptera,  368 


Owls,  utility  of,  130,  168 
Ownership  defined,  66 

P. 
Pannage,  31,  87,  171 
Pustui-e,  forest,  35,  86 
Peridermium  Pini,  441 

,,  (acicola),  461 

Pestalozzia  Hartigii,  460,  481 
Peziza  Willkommii,  454 
Pheasants,  138 
Phytophthora  Fagi,  482 

,,  omnivora,  482 

Pig,  wild.  111,  167 
Pigeons,  139 
Pine  beauty,  320 

,,    beetle,  265 

,,    blister,  441 

,,    branch-twist,  444 

,,    looper  moth,  326 

„    moth,  294 

,.    needle-cast,  465 

,,    shoot  tortrix,  335 
Plant  lice,  361 
Poison  for  mice,  134 
Polecats,  117,  129,  167 
Polytrichum,  50,  407,  409 
Polj'porus  fulvus,  451 
sp.,  440,  476 
,,  sulphurous,  440,  475 

Porcupines,  135 
Property  defined,  64 

E. 
Rabbits,  3,  116 
Rain,  554 
R<its,  124 
Red  deer,  97,  99 
,,    rot,  439,  673 
Resin,  28 
Retinia  sp.,  235 
Rhizina,  437 
Rhytisraa  acerinum,  483 
Rights  of  common,  69 

,,      to  water,  90 

,,      of  way,  90 
Rime  frost,  574 


12 


INDEX. 


Rodents,  114 
Hoe  deer,  110 
Rooks,  1.30,  335 
Root  fungi,  429,  473 
Roselliniu  qiiercina,  473 
Rove  beetles,  181 


Sand  dimes,  G'21 
„     inland.  G30 

Sawflios,  349 

Scale  insects,  3<)0 

Septoria  parasitica,  4 GO 

Servitudes,  G7 

Sheep,  40,  167 

Shrews,  129 

Shrikes,  1G8 

Silver-fir  canker,  44S 

Sirex,  1-18 

Snowbreak,  oGl 

Softwoods,  81,  9.S 

Soil  denudation,  .j82 

Sphaerella  laricinu,  469 

Sphagnum,  50,  409 

Spiders,  173 

Spraying  plants,  177 

Spruce  canker,  452,  477 
,,  cone  fungus,  472 
,,       needle  rust,  463 

Squirrels,  118 

Stagheadedness,  680 

Stai'lings,  167 

Stereum  hirsutum,  477 

Stoats,  117,  129,  167 

Stones  in  forests,  52 

Stonns,  531 

Sulphurous  acid  fumes,  696 

Swamps,  596 

Sycamore  leaf-blotch,  483 

T. 
Taclunae,  173.,  195,  316 
T.'mplat.",  IS 


Termites,  199 
Tiger  beetles,  180 
Tineidae,  343 
Tomicus  typograi)hus,  238 
Tomtits,  167,  244 
Tortricidae,  331,  454 
Tree  traps,  176 
Trametes  radiciperda,  435 

Pini,  438 
Trichosphaeria  parasitica,  470 
Turnip  dart  moth,  325 
Turpentine,  28,  84 


Uprooting  by  frost,  510 
Utilisation  of  forests,  23 


Voles,  124 


W. 


Wasps,  188 
Wax,  collection  of,  53 
Weasels,  117,  129,  167 
Weeds,  386 

,,      hosts  of  fungi,  418 
Weevils,  217 
White  rot,  439,  679 
Willow  beetle,  285 

,,      leaf- blister,  485 
Windbreak,  113,  550,  553 
Windfalls,  rights  to,  83 
Winds,  513,  527 
Windsor  forest,  3,  334 
Winter  moth.  329 
Witches'  broom,  447 
Woodpecker,  76,  142,  214 
Wood- wasps,  355 
Woolly  aphis,  366 
Wrens,  167,  214 


KNI)   OF    VOI.UMK    IV. 


C' 


BKAUBl'KV,    AONEW,    (i    ro. 


TONBKIDliE. 


Library