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1    H  JV;1  U  UJ 

NATI    RE- Si 


THE    BOOK    OF    NATURE    STUDY 


Draivn  by  Bertha  Reid 


CLIMBING   HEDGEROW   PLANTS 


1.  Woody  Nightshade 

2.  Clematis 


3.  Honeysuckle 

4.  Blackberry 


THE    BOOK    OF 

NATURE  STUDY 


EDITED   BY 


J.    BRETLAND    FARMER 

M.A.,  D.Sc.(OxoN.),  F.R.S. 

PROFESSOR  OF  BOTANY,   ROYAL  COLLEGE  OF  SCIENCE,    LONDON 


ASSISTED     BY 

A   STAFF   OF   SPECIALISTS 


FULLY    ILLUSTRATED 


VOL.     V 


LONDON: 

THE    CAXTON    PUBLISHING    COMPANY 
CLUN  HOUSE,  SURREY   STREET,  W.C. 


V 


Nl.S 


CONTENTS    OF    VOLUME    V 

CHAPTER   I 
XEROPHYTIC  VEGETATION 

PAGE 

SEASHORE  VEGETATION  ........         i 

CHAPTER   II 
AQUATIC  VEGETATION     .  .  .  .  .  .  .  .21 

CHAPTER   III 
THE  VEGETATION  OF  MEADOWS  AND  PASTURES  .  56 

CHAPTER   IV 
THE  WEEDS  OF  CULTIVATION    .  .....       75 

CHAPTER  V 

THE  SCHOOL  GARDEN 

GENERAL  .........      89 

CHAPTER   VI 

SELECTION  OF  SITE  AND  PRELIMINARY  OPERATIONS     .  .  .  .96 

CHAPTER  VII 
TILLAGE  OPERATIONS  AND  MANURING  .  .  .  .  .  .108 

CHAPTER  VIII 
MULTIPLICATION  OF  PLANTS       ....  .  .     113 

CHAPTER   IX 

VEGETABLE  CULTURE     .  .  .  .  .  .  ,  .125 


vi  CONTENTS  OF  VOLUME  V 

PAGE 

CHAPTER  X 
FRUIT  CULTURE.  .  .  .  .  .  .  .148 

CHAPTER   XI 
FLOWERS  ........  166 

CHAPTER  XII 

INSECT  AND  FUNGOID  ENEMIES  OF  GARDEN  CROPS     .  .  .  ,     180 

CHAPTER  XIII 
THE   WORK  OF  THE  SOIL 
THE  ORIGIN  OF  SOILS   ..... 


LIST    OF    PLATES— VOLUME    V 

COLOURED  PLATES 

PAGE 

CLIMBING  HEDGEROW  PLANTS.     Drawn  by  BERTHA  REID  .  .  Frontispiece 

A  MEADOW.     Drawn  by  BERTHA  REID             .            .  .  .  .64 

AN  OLD  GARDEN.     Drawn  by  ANNA  LEA-MERRITT     .  .  .  .160 

A  ROCK  GARDEN.     Drawn  by  LILIAN  STANNARD        .  .  .  .112 

BLACK  AND    WHITE  PLATES 

SALICORNIA  PLANT  ASSOCIATION — VEGETATION  OF  MUDDY  SHORE     .  .        2 

OUTER  FRINGE  OF  SAND  HILLS— A  CLUMP  OF  EUPHORBIA  PARALIAS  (Sea 

Spurge)  AMONG  THE  MARRAM  GRASS         .  .  .  .  -4 

SEA  SPURGE  AMONGST  MARRAM  GRASS — SALSOLA  KALI  (Saltwort)     .  .        6 

HORNED  POPPY  IN  FRUIT   AND  FLOWER  ON  SHINGLE — OPEN  ASSOCIATION 

OF   A   NEWLY   FORMED   SHINGLE   BEACH         .  .  .  .  .12 

DITCH  IN  A  PEAT  MOOR,  COMPLETELY  FILLED  WITH  BUR-REED         .  .       34 

HEDGEROW  VEGETATION  BY  A  STREAM — A  HAWTHORN  HEDGE          .  -72 

A  HEDGEROW  IN  SPRING          .......       74 

ROYAL  HORTICULTURAL  SOCIETY'S  GARDENS,  WISLEY  .  .  .  .96 

ROYAL    HORTICULTURAL    SOCIETY'S    GARDENS,   WISLEY — A    CLASS    IN    THE 

LABORATORY     ........   96 

BOYS  AND  GIRLS,  AGED   ELEVEN  TO  THIRTEEN,  AT  WORK  ON  HERBACEOUS 

AND  ROSE  BORDERS,  JUNE  .  .  .  ,  ,  .128 

vii 


viii  LIST  OF  PLATES— VOLUME  V 

PAGE 

HALE  CONTINUATION  SCHOOL  GARDENS,  FARNHAM      .  .  .  -144 

HALE  DAY  SCHOOL  GARDENS,  FARNHAM,  SURREY       .  .  .  .176 

FARNHAM  EAST  STREET  SCHOOL  GARDENS       .  .  .  .  .184 

A  QUARRY  IN  THE  HYTHE  BEDS  (LOWER  GREENSAND)          .  .  .188 

A  QUARRY  IN  THE  CHARNWOOD   FOREST,  SHOWING  GLACIAL  DRIFT,  ETC.  .     192 

WATER  RETAINED  BY  EQUAL  WEIGHTS  OF  VARIOUS  SOILS — PHOTOGRAPHS 
OF  CULTURES  OF  SOIL  ORGANISMS — EXPERIMENT  TO  ILLUSTRATE  THE 
RISE  OF  WATER  IN  SOILS  BY  CAPILLARITY  OR  SURFACE  TENSION  .  204 

PHOTOGRAPH  OF  TURF  FROM  TWO  OF  THE  GRASS  PLOTS  AT  ROTHAMSTED,  ONE 
OF  WHICH,  A,  HAS  BEEN  RECEIVING  AN  EXCLUSIVELY  NITROGENOUS 
MANURE,  AND  THE  OTHER,  B,  PHOSPHATES  AND  POTASH  ONLY  FOR 

MORE   THAN   FlFTY   YEARS    .......       208 


THE  BOOK  OF  NATURE  STUDY 


XEROPHYTIC    VEGETATION. 

BY  CHARLOTTE  L.  LAURIE, 
Assistant  Mistress,  Cheltenham  Ladies'  College. 

CHAPTER   I 
SEASHORE  VEGETATION 

IT  would  be  difficult  to  find  a  country  with  a  more  varied 
coast-line  than  that  of  our  islands.  The  chalk  of  Kent, 
the  sandstone  of  Devon,  the  granite  and  serpentine  of  Cornwall, 
the  limestone  of  S.  Wales, — all  combine  to  produce  a  variety  of 
coast  almost  unknown  elsewhere  in  so  short  a  distance.  Every 
type  of  shore  is  to  be  found  in  these  islands  :  gravel  beaches,  bold 
rocky  headlands,  great  stretches  of  sand,  deep  bays,  wide  estuaries  ; 
and  each  has  its  characteristic  vegetation. 

It  will  be  most  convenient  to  arrange  this  great  variety  of 
types  in  the  following  groups  : — 

1.  The  Plant  Associations  of  muddy  banks. 

2.  ,,  „  sandy  shores  and  sand-dunes. 

3.  ,,  ,,  pebble  banks  and  shingle. 

4.  ,,  „  rocky  headlands. 

THE  VEGETATION  OF  MUDDY  SEASHORES. — Mud  plants  may  be 
studied  at  the  estuary  of  any  tidal  river  ;  the  shores  of  the  Bristol 
Channel  afford  excellent  examples  of  the  plants  belonging  to 
mudd}'  salt  marshes,  owing  to  the  fact  that  the  tides  are  there 

VOL.  V. — I 


&\l  :  THE 'BOOK  OF  NATURE  STUDY 

particularly  high,  and  the  channel  bed  is  formed  of  soft,  muddy 
materials.  The  vegetation  is  xerophytic  in  character,  for  a 
muddy  salt  marsh  has  great  extremes  of  heat  and  cold,  of  moisture 
and  dryness.  The  plants  are  characterised  by  a  low  growth, 
a  comparatively  undeveloped  root-system,  and  fleshy  leaves ;  or 
by  fleshy  stems  bearing  leaves  very  much  reduced  in  size.  At  each 
high  tide  the  waters  of  such  a  shallow  channel  as  the  Bristol 
Channel  lay  down  a  considerable  thickness  of  mud  ;  thus  the 
formation  of  a  muddy  salt  marsh  begins.  Soon  there  will  be 
a  layer  of  mud,  washed  by  all  high  tides.  Here  the  Glasswort 
(Salicornia  herbacea)  establishes  itself ;  often  it  is  the  only 
species  found.  The  accompanying  photograph  shows  the  plants 
some  distance  apart,  not  competing  in  any  way  with  each  other. 
A  few  green  seaweeds  may  be  found  in  this  belt,  and  sometimes 
the  Suceda  maritima.  When  the  Glasswort  grows  thickly  it 
covers  the  mud-flats  with  a  sheet  of  vivid  green,  which  changes 
to  brown  in  autumn ;  of  all  the  plants  growing  in  salt  marshes, 
it  is  the  one  that  creeps  farthest  down  to  the  sea ;  the  first  belt 
or  zone  of  vegetation  in  these  muddy  shores  is  therefore  that  of 
the  Salicornia  herbacea.  The  plant  has  short,  thick  leaves,  and  a 
stem,  succulent  above,  which  bears  branches  given  off  in  pairs  at 
each  node,  and  these  again  branch,  each  ending  in  a  spike.  The 
flowers  are  very  minute,  with  a  green  perianth,  one  or  two 
stamens  and  two  styles  projecting  from  the  perianth.  The 
Suceda  maritima  belongs  to  the  Goosefoot  family,  and  is  a  low- 
growing  plant,  sometimes  only  two  or  three  inches  high.  It  has 
small,  linear,  succulent  leaves  and  small,  green  flowers,  two  or 
three  together  in  the  axils  of  the  leaves.  It  forms  a  sub- 
dominant  species. 

Behind  the  Salicornia  belt,  another  Plant  Association,  that  of 
the  grass,  Glyceria  maritima,  establishes  itself.  Here  the  mud  bank 
is  rather  higher  and  the  ground  is  washed  by  spring  tides  only  in 
time  of  storms.  This  situation  is  therefore  drier  than  the  last. 
The  two  plants  most  usually  found  with  this  grass  on  the  shore  in 
question  are  the  Sea  Starwort  (Aster  Tripolium)  and  the  Sea  Arrow- 
grass  (Triglochin  maritimum).  The  Sea  Aster  is  distinguishable 
from  all  other  British  Composites  by  its  large  flower  heads,  with 
a  yellow  disc  and  purple  ray.  It  is  seldom  more  than  a  foot  high. 


From  Mr.  J.  H.  Priestley,  University  College,  Bristol. 

SALICORNIA  PLANT  ASSOCIATION 


Juncus 

Gerardii 

Associat 


[•lyceria 
laritima 
I'riglochin  | 
laritimur 
nd  Aster 
''ripolium 


j»i  Mr.  J.  H.  Priestley,  University  College,  Bristol. 

VEGETATION  OF  MUDDY  SHORE 


VEGETATION  OF  MUDDY  SEASHORES  3 

The  Sea  Arrow  Grass  is  a  plant  usually  abundant  in  salt  marshes, 
and  belonging  to  the  same  order  as  the  Water  Plantain,  namely,  to 
the  Alismaceae.  The  leaves  are  succulent,  and  come  up  from  the 
underground  stem.  The  flower-stems  have  no  leaves,  but  bear 
spikes,  from  six  to  twelve  inches  high,  of  small  yellowish-green 
flowers.  This  Glyceria  Plant  association,  as  it  may  be  called, 
is  shown  in  the  foreground  of  the  accompanying  photograph  ; 
it  is  usually  the  second  association  to  be  formed  on  muddy  sea- 
shores. In  the  same  photograph,  another  association  is  seen 
occupying  the  topmost  zone.  The  dominant 
plant  is  a  Rush  (Juncus  Gerardii),  and 
associated  with  that  are  the  Sea  Thrift 
(Armeria  maritima)  and  the  Sea  Milkwort 
(Glaux  maritima).  The  Mud  Rush  (Juncus 
Gerardii)  has  brown  shining  bracts.  It  is 
marked  off  from  other  species  of  Rush  by 
the  leaves  of  the  perianth  being  about  equal 
to  that  of  the  capsule.  The  Sea  Milkwort 
belongs  to  the  Primulaceae,  but  differs  from 
the  other  genera  of  that  order  in  having  no 
corolla.  The  calyx  is  petaloid  and  consists 
of  five  pink  sepals.  It  is  a  slender  plant, 
about  six  inches  high,  with  small  leaves. 
Another  plant  often  found  in  this  belt  is 
the  Scurvy  Grass,  one  of  the  Cruciferae, 
with  small  white  flowers  and  succulent 
leaves.  This  topmost  zone  of  vegetation 

is  washed  only  at  very  high  tides,  the  Fia  '- krt  (Glaux 
ground  is  therefore  far  drier.  As  the 
salt  marsh  gets  drier  and  able  to  support  a  more  fixed  vege- 
tation, cattle,  sheep,  and  horses  may  be  turned  in  to  graze  on  it, 
and  the  land  gradually  becomes  reclaimed.  The  "  Levels  "  of 
Somerset  consist  very  largely  of  land  of  this  character.  The 
effect  of  turning  in  cattle  to  graze  is  to  produce  considerable 
change  in  the  vegetation,  some  plants  being  kept  down  altogether. 
It  is  interesting,  as  one  walks  over  a  salt  marsh  pasture,  to  picture 
the  stages  that  have  followed  each  other :  at  one  time,  it  may  have 
been  a  muddy  belt  with  only  patches  of  Glasswort  on  it ;  then  as 


4  THE  BOOK  OF  NATURE  STUDY 

the  level  of  the  mud  rose  and  only  high  tides  could  reach  it,  other 
plants  were  able  to  gain  a  footing  ;  the  marsh  in  time  got  solid 
enough  for  animals  to  be  turned  in  on  it,  and  then  the  stage  is 
reached  in  which  man's  influence  becomes  the  dominant  factor. 
In  ecological  botany  the  term  Plant  Formation  is  now  used 
to  denote  the  total  number  of  Plant  associations  which  succeed 
each  other  in  a  rapid  succession  in  the  way  just  described ;  as 
long  as  the  plants  of  one  association  are  giving  place  to  another, 
the  association  is  said  to  be  open ;  when  the  final  stage  is 
reached  and  the  vegetation  is  fixed  or  stable,  the  association  is 
closed,  and  there  may  be  intermediate  stages.  Thus  the  Sali- 
cornia  and  Glyceria  associations  are  open,  the  Juncus  associa- 
tion is  intermediate,  whilst  that  of  the  salt  marsh  pasture,  showing 
as  it  does  the  influence  of  man,  has  been  called  a  "  substituted  " 
association. 

The  influence  of  a  tidal  river  on  vegetation  is  by  no  means 
limited  to  the  formation  of  salt  marshes  with  their  characteristic 
plants  at  its  estuary.  The  Severn,  for  instance,  affects  the 
vegetation  of  Gloucestershire  not  only  at,  or  near,  its  mouth,  but 
to  a  considerable  distance  inland,  with  the  result  that  many 
plants  usually  found  on  seashores  occur  almost  in  the  middle  of 
what  is  practically  an  inland  county.  The  following  may  be 
mentioned : — 

The  Sea  Milkwort  at  Beachley  Point,  6  miles  from  Portskewet 
at  the  mouth. 

The  Sea  Scurvy  grass  at  Lydney,  14  miles  from  Portskewet. 

The  Sea  Spurrey  at  Slimbridge,  16  miles  from  Portskewet. 

The  Sea  Plantain  at  Longny,  20  miles  from   Portskewet. 

The  Sea  Starwort  at  Newnham  on  Severn,  20  miles  from 
Portskewet. 

The  Severn  is  a  particularly  good  instance  of  a  tidal  river, 
and  has  a  tidal  bore,  so  that  the  effect  on  vegetation  would  be 
more  marked  than  in  many  others. 

THE  VEGETATION  OF  SANDY  SEASHORES.  —  It  will  happen 
that  some  classes  may  be  able  to  make  observations  without 
much  difficulty  on  the  vegetation  of  sandy  seashores.  It  has 


Photo  by  Dr.  Pethybridge,  Royal  College  of  Science,  Dublin. 

OUTER  FRINGE  OF  SAND  HILLS 

With  Triticum  junceum  (dominant),   Salsola,  and  Atriplex  in  the  foreground 
Psamma  on  hills  to  the  left 


l''ro»t  Dr.  Pethybridge,  Royal  Collrge  of  Science,  Dublin. 


A  CLUMP  OF  EUPHORBIA  PARALIAS  (Sea  Spurge)  AMONG 
THE  MARRAM  GRASS 


VEGETATION  OF  SANDY  SEASHORES  5 

been  estimated  that  nine-tenths  of  the  coast-line  of  the  world 
are  fringed  by  sands.  Sand-dunes  which,  as  will  be  shown,  are 
largely  built  up  by  plants,  extend  for  miles  along  many  parts 
of  our  shores,  on  the  coast  of  Holland,  and  along  the  east 
coast  of  the  United  States.  To  find  plants  in  their  natural 
habitat,  it  is  best  to  avoid  the  fashionable  seaside  resort,  and 
to  spend  a  summer  holiday  in  some  primitive  spot,  if  pos- 
sible, away  from  esplanades,  piers,  bands,  and  trippers.  The 
following  observations  were  made  in  a  little  village  of  North- 
umberland where  the  sands  stretched  for  miles  and  were 
practically  undisturbed.  Walking  on  the  sands,  one  soon 
realised  that  there  was  an  area  with  very  few  plants,  owing  to 
the  constant  blowing  about  of  the  sand  by  the  wind ;  this  may 
be  called  the  area  of  shifting  sand.  The  two  most  common 
plants  of  this  belt  were  the  Sea  Rocket  (Cakile  maritima)  and 
the  Saltwort  (Salsola  Kali}.  The  former  is  a  cruciferous  plant 
with  fleshy  leaves  and  lilac  flowers.  The  pods  are  worth  noticing. 
Each  divides  into  two  portions,  a  short  lower  and  a  long  upper 
segment.  The  upper  portion  falls  off  in  the  autumn,  the  seed 
gets  buried  in  the  sand  and  germinates  the  following  spring. 
The  leaves  of  the  Saltwort  are  not  only  succulent,  but  prickly. 
The  plant  is  usually  about  six  inches  high,  and  bears  minute 
flowers  in  the  axils  of  the  upper  leaves.  In  many  places  the 
Sea  Wheat-Grass  (Triticum  junceum)  is  the  first  plant  to 
establish  itself  on  the  drifting  sand.  This  is  shown  in  the 
photograph  by  Dr.  Pettybridge,  who  has  investigated  the  Plant 
associations  of  the  Dublin  district.  The  Sea  Wheat-Grass  is 
seen  in  the  foreground,  and  associated  with  it  the  Saltwort  and 
the  Sea  Purslane  (Atriplex  portulacoides) .  This  grass  has  creeping 
underground  stems  (stolons),  and  these  help  to  fix  the  loose  sand. 
Within  the  area  of  shifting  sand  comes  a  belt  of  sand  in  which 
the  wind  has  not  free  play,  for  certain  grasses  and  other  plants 
have  begun  to  bind  the  sand  together,  weaving  it  into  a  soil  of 
firmer  texture  than  shifting  sand  can  have.  The  Marram  Grass 
(Psamma  arenaria)  and  the  Sand-Lyme  Grass  (Elymus)  are  the 
two  species  most  commonly  found.  Both  these  grasses  have  long 
rhizomes,  which  bind  the  sand  as  they  spread  in  matted  tufts. 
The  Marram  may  easily  be  distinguished  from  the  Lyme  Grass 


6  THE  BOOK  OF  NATURE  STUDY 

by  the  fact  that  its  spikelets  contain  only  one  perfect  flower, 
whilst  the  Sand-Lyme  Grass  usually  has  three  perfect  flowers  in 
I  each  spikelet.  Both  have  leaves 

which  can  roll  in,  and  thus  protect 
the  plant  from  too  rapid  transpira- 
tion. The  structure  of  the  leaf  is 
shown  in  Fig.  2.  In  wet  weather, 
or  in  diffuse  light,  the  leaves  are 
spread  out  flat,  but  in  scorching 
suns  and  drying  winds  the  upper 

FIG.  2.-Leaf  of  Psamma  (transverse    surface   rolls    inwards,   Owing    to    the 
section).      J,   Position   of  stomata  ;  ..  .  .     .  .. 

m,  motor  cells;   /,  under  surface;    Contraction  of  Certain  Cells. 

e,  upper  surface.  The   stomata  are  on  the  upper 

surface,  and  are  completely  sheltered  by  the  inrolling  of  the 
leaf.  Very  often  with  these  two  grasses,  the  Sand  Sedge 
(Carex  arenaria)  is  also  found  ;  it  too  has  a  creeping  root- 
stock  and  is  a  sand  binder,  but  undoubtedly  the  most  common 
binder  is  the  Marram  Grass.  Other  plants  soon  find  a  lodg- 
ment in  the  sand  which  is  no  longer  being  blown  about ;  the 
Spiny  Restharrow  is  often  very  conspicuous,  carpeting  the 
ground  to  the  very  edge  of  the  shifting  belt ;  mixed  with  this 
may  be  found  the  Stork's  Bill  (Er odium  cicutarium),  a  plant  be- 
longing to  the  Geraniaceae,  but  differing  from  the  Geranium  in 
having  pinnate,  not  palmate,  leaves,  and  five  instead  of  ten 
stamens.  The  long  beaks  of  the  fruit  are  very  characteristic  ; 
they  twist  themselves  spirally,  but  the  carpels  do  not  open  to  let 
out  the  seeds,  as  in  the  Geraniums.  A  geranium  that  is  very 
abundant  on  this  part  of  the  Northumberland  coast  is  the  Blood 
Geranium  ;  this  has  large,  purplish-red  flowers,  which  are  very 
striking  on  the  sand  mounds  and  hills  against  the  brownish  grass. 
This  is  a  very  local  plant,  but  is  usually  abundant  when  it  occurs 
at  all.  The  well  known  Bird's-foot  Trefoil  and  the  Mallow  are 
also  common.  One  more  plant  must  be  mentioned  as  characteristic 
of  this  situation,  the  Sea  Purslane  (Arenaria  peploides),  which 
also  has  a  creeping  root-stock  and  is  a  sand  binder.  The  leaves 
are  thick  and  fleshy,  and  the  fruits  are  large  compared  with  those 
of  other  species  of  Sandwort. 

The  Plant  associations  to  be  studied  on  sandy  seashores  are  : 


From  Dr.  Pethybridge,  Royal  College  a/Science,  Dublin. 

SEA  SPURGE  AMONGST  MARRAM  GRASS 


From  Dr.  Peth  bridge,  Royal  College  ofSciencet  Dublin. 

SALSOLA  KALI  (Saltwort) 


VEGETATION  OF  SANDY  SEASHORES  7 

(i)  Those  belonging  to  shifting  sands  ;  in  different  parts  of  the 
country,  different  plants  will  be  found,  but  the  most  common  are 
the  Sea  Rocket  and  the  Saltwort ;  this  may  therefore  be  called 
a  Salsola-Cakile  Plant  association.  (2)  The  Marram  association, 
situated  more  landward  and  characterised  by  the  formation  of 
sand-dunes,  owing  to  the  binding  powers  possessed  by  the  rhizomes 
of  the  plants.  Here  the  part  played  by  the  wind  may  be  noticed. 
Coming  in  contact  with  sand,  the  wind  drives  it  onwards,  piling 
it  into  irregular  heaps  and  ridges  called  "  dunes. "  Their  general 
direction  is  transverse  to  the  prevalent  course  of  the  wind.  The 
coast  of  Norfolk  is  fringed  with  sand-hills,  fifty  to  sixty  feet  high. 
Long  tracts  of  blown  sand  are  found  on  the  Scottish  and  Irish 
coast-lines.  Sand-dunes  extend  for  many  miles  along  the  French 
coast,  and  Flanders  and  Holland  ;  off  Holland  they  are  occasionally 
over  two  hundred  feet,  though  their  average  is,  as  in  Norfolk, 
fifty  to  sixty.  When  not  fixed  by  sand  binders,  the  dunes  may 
travel  inland.  On  the  low  shores  of  the  Bay  of  Biscay  their  rate 
is  about  sixteen  feet  per  annum,  and  in  their  progress  they  have 
at  times  overwhelmed  whole  districts.  This  destruction  is  now 
prevented  by  the  planting  of  pine  forests. 

In  making  observations  on  the  flora  of  a  sand-dune,  the  plants 
found  in  the  hollow  between  the  summits  of  the  dune  will  be 
greater  in  number  and  variety,  for  the  position  is  more  sheltered, 
the  force  of  the  wind  is  less  felt,  and  there  is  more  shade.  These 
all  help  to  form  a  thick  sward,  which  renders  the  sand  less  liable 
to  be  blown  about.  The  next  stage  is  the  formation  of  a  dune 
pasture.  Here  there  are  many  more  plants  present.  The  most 
abundant  are  Centaury,  Convolvulus,  Thyme,  Ragwort,  Plantain, 
and  Chamomile. 

The  following  table  is  an  attempt  to  compare  the  Plant  For- 
mations of  muddy  and  sandy  seashores  ;  the  figures  denote  the 
order  of  succession. 

PLANT  FORMATIONS 

MUDDY   SHORES  SAXDY   SHORES 

_  ( Sea  Wheat -Grass 
(i.  Sahcornia  I-\Q  ,    , 

PLANT  °Pen"  {2. 


Glyceria  fluitans       2.  Psamma 
Juncus  Gerardii        3.  Sward-fo: 
Substituted     4.  Salt  Marsh  pasture  4.  Dune  pasture 


:s   Intermediate  3.  Juncus  Gerardii        3.  Sward-forming  Plants 


THE  BOOK  OF  NATURE  STUDY 


These  plants  have  many  features  in  common ;  the  most  im- 
portant is  the  structure  of  the  leaf,  the  organ  which  more  than 

any  other  responds  to  the  environment. 
Some  of  these  plants  adapt  themselves  to 
their  surroundings  by  the  reduction  of  their 
leaf  surface  ;  others  by  developing  a  water- 
storage  tissue  which  makes  the  leaf  succulent. 
The  reduction  of  the  leaf  surface  is  one  of 
the  means  by  which  a  plant  prevents  the 
loss  of  water.  In  the  Salicornia  the  leaves 
are  scarcely  distinguishable  from  the  fleshy 
stem,  immediately  under  the  epidermis  of 
which  are  two  rows  of  cells  filled  with  chloro- 
phyll granules.  The  same  object  of  restrict- 
ing the  loss  of  water  is  attained  in  the 
Marram  Grass  by  the  inrolling  of  the  leaf, 
and  in  other  plants  by  the  thickening  of  the 
outer  skin,  or  by  a  covering  of  hairs,  or 
the  formation  of  a  waxy  layer,  forming 
the  bloom  which  is  so  often  noticed  on 
seashore  plants. 

The  stems  of  these  plants  also  show  special  modifications 
of  structure.  They  have  much  less  woody  tissue,  for  there  is 
less  conduction  of  water ;  on  the  other 
hand,  they  have  a  greater  development 
of  assimilating  tissue.  Most  of  them 
have  creeping  rhizomes. 

The  low  growth  of  many  of  these 
plants  is  another  noticeable  feature  ; 
even  shrubs  are  prostrate.  The  Creep- 
ing Willow  is  a  case  in  point.  It  is  a 
low,  straggling  shrub ;  the  stems  creep 
underground,  rooting  at  the  nodes,  and 
only  ascend  above  the  soil  to  a  foot  or 
more.  It  has  the  regular  type  of 
Willow  leaf,  and  these  are  silky  on 
both  surfaces. 

This  stunted  growth  of  plants  is 


FIG.  3.— Creeping  Willow 
(Salix  repens}. 


FIG.  4.— Stork's  Bill  (Erodium 


VEGETATION  OF  SHINGLE  9 

characteristic  not  only  of  seashores,  but  of  high  hills, — of  any 
situation,  in  fact,  where  the  supply  of  water  is  irregular.  Some 
plants  frequent  both  situations  :  the  Stork's  Bill  is  found  on  hills 
about  eight  or  nine  hundred  feet  high  as  well  as  on  sandy  shores ; 
the  Wild  Thyme,  and  some  of  the  Bedstraws  are  other  instances. 

These  plants  are  found  not  only  or*  the  seashore,  but  inland, 
in  deserts  where  there  is  a  certain  amount  of  salt.  Travellers 
note  in  sand  deserts,  in  addition  to  various  species  of  Cacti  and 
Spurges,  the  Glasswort  or  Marsh  Samphire,  the  Sea  Plantain,  and 
various  members  of  the  Goosefoot  family. 

THE  VEGETATION  OF  SHINGLE. — Sometimes  the  beach  is  covered 
with  shingle,  the  pebbles  of  which  are  derived  partly  from  the 
cliffs  above,  and  partly  from  the  inrolling  waves,  which  often  carry 
with  them  sand  and  stones,  depositing  them  on  the  shore.  The 
action  of  seaweeds,  as  Lord  Avebury  has  suggested,  is  here  of  great 
influence.  "  They  attach  themselves/ '  he  says,  "  to  the  rock,  and 
grow  towards  the  surface,  many  of  them  being  floated  upwards  by 
the  presence  of  innumerable  air  vessels.  The  waves  as  they  pass 
drag  the  weeds  with  them,  tear  up  the  stones,  and  throw  them  on 
the  shore.  Some  beaches  are  almost  entirely  supplied  with 
pebbles  in  this  way  by  seaweeds."  On  most  beaches  two  lines  of 
seaweed  may  be  seen,  one  marking  the  high-water  at  the  last 
spring  tide,  one  the  high-water  line  of  the  last  tide.  Between 
these  two,  other  lines  of  seaweed  may  occur,  showing  the  high- 
water  level  during  some  storm.  There  are  three  main  groups 
of  seaweeds  :  the  Olive  Brown,  the  Red,  and  the  Green.  The 
most  common  species  of  the  first  named  is  the  Brown  Bladderwrack 
(Fucus  vesiculosus) .  It  is  like  a  long  ribbon  with  a  thick  midrib. 
Here  and  there  are  large  bladders  filled  with  air,  which  enables 
the  plant  to  float.  The  whole  frond,  as  it  is  popularly  called,  is 
fastened  by  a  root-like  portion  to  the  rock.  The  size  of  this 
seaweed  varies  very  much  :  in  muddy  ground  it  may  not  be  more 
than  an  inch  or  two  ;  in  more  favourable  situations  it  may  be 
3  feet  long.  Little  indentations  like  pimples  may  be  seen  at 
the  summit  of  some  of  the  branches  ;  these  cavities  contain  the 
reproductive  organs.  The  Brown  Seaweeds  are  burnt  for  the 
manufacture  of  kelp.  The  Wracks  are  not  the  best  ones  to 


io  THE  BOOK  OF  NATURE  STUDY 

use  for  this  purpose,  only  the  Oarweeds  or  Laminaria  should  be 
employed.  It  is  these  thick  Brown  Seaweeds  that  make  the  rocks 
so  slippery,  and  necessitate  very  careful  walking.  The  stem  of 
the  Laminaria  is  very  strong,  and  is  used  for  making  handles  to 
knives.  When  fresh,  the  stem  is  soft  enough  to  allow  the  end  of 
a  knife-blade  to  be  thrust  longitudinally  into  it.  A  portion  of 
the  stem,  long  enough  for  the  knife  handle,  is  cut  off,  and  in  a  few 
months  it  dries,  contracting  with  such  force  as  to  fix  the  blade  ; 
the  dried  stem  has  the  appearance  and  toughness  of  stag's  horn. 

The  Red  Seaweeds  are  particularly  beautiful  from  the  variety 
of  their  colouring.  They  are  many  of  them  very  minute,  often 
only  a  few  inches  in  length.  These  are  best  seen  in  the  shallow 
pools  of  water  left  by  the  retreating  tide  on  the  rocks.  In  such 
situations  the  variety  of  colouring  is  enhanced  by  the  background 
of  the  rock  and  the  transparency  of  the  water,  when  the  sun  is  on 
it,  provided  the  light  is  not  too  intense.  Some  of  these  Seaweeds 
are  used  as  articles  of  food  ;  the  Irish  or  Carrageen  Moss  (Chondrus 
crispus)  is  one  of  the  best  known.  When  boiled  it  forms  a  thick, 
colourless  jelly  that  is  said  to  be  very  nutritive.  The  Sea 
Lettuce  and  the  Purple  Laver  are  often  eaten  ;  they  should  be 
gathered  in  the  winter,  or  early  spring,  and  stewed  for  several 
hours. 

If  Seaweeds  are  being  collected  for  a  herbarium,  they  should  be 
well  washed  in  fresh  water,  in  order  to  get  rid  of  the  salt ;  then 
pieces  of  card  the  size  required  should  be  slipped  under  them  as 
they  float  in  the  water.  In  this  way  it  is  possible  to  spread  out 
all  the  branches.  The  Seaweeds  have  in  them  a  certain  gelatinous 
substance,  which  usually  glues  them  down  firmly  to  the  paper  ; 
if  necessary  they  may  be  fixed  by  the  gelatine  obtained  from 
boiling  down  the  Iceland  Moss. 

The  flowering  plants  belonging  to  pebbly  beaches  have  either 
long  tap  roots  which  penetrate  between  the  loose,  dry  stones,  and 
reaching  the  subsoil  get  food  material  and  water  from  it  ;  or  they 
have  a  shallow  root-system,  adapted  to  the  less  dry  portion  of  the 
bank.  To  the  former  group  belong  the  Horned  Poppy  and  the 
Sea  Holly  ;  to  the  latter  the  Sea  Purslane. 

The  Horned  Poppy  (Glaucium  flavwn)  is  so  named  from  the 
long  curved  pods  with  two  stigmas.  These  fruits  may  be  even 


VEGETATION  OF  SHINGLE 


ii 


10  or  12  inches  long,  and  are  a  very  striking  feature  of  the  plant. 
The  other  characters  are  those  of  the  common  Poppy  :  a  calyx 
of  two  sepals,  which  drop  off  as  the  flower  opens,  four  petals  and 
numerous  stamens,  which  in  this  species  are  orange.  The  flowers 
are  very  showy,  being  large  and  yellow,  and  the  leaves  have  a 
silvery  tint  from  the  rough,  thick  hairs  which  clothe  them.  The 
Sea  Holly  is  an  equally  striking  plant.  Its  foliage  is  greyish-green, 
the  upper  leaves  and  bracts  having  an  edging  of  the  brightest 
blue  ;  the  flowers  are  also  blue.  The  leaves  are  very  thick,  with  a 
'  bloom"  on  them.  They  are  four  or  five  inches  across,  and  by 
their  great  breadth  protect  the  stem  and  roots  from  the  scorching 
sun ;  their  spiny  margins  prevent  the 
plant  being  eaten  by  animals.  The 
plant  belongs  to  the  Umbelliferse, 
and  the  flower-heads  are  protected 
as  is  usual  in  umbelliferous  plants 
by  bracts,  which  like  the  leaves  are 
spiny.  Each  flower  has  a  prickly 
calyx,  and  the  fruit  is  also  prickly. 
The  long  underground  stems  are 
sometimes  candied  and  used  as  a 
sweetmeat  ;  if  the  plant  were  not 
well  protected  by  its  thorniness  it 
would  probably  soon  be  extirpated 
by  animals. 

The  Sea  Purslane  (Arenaria  pep- 
loides)  is  one  of  the  Sandworts,  and 
belongs  to  sandy  shores  quite  as  much  as  to  pebbly  beaches. 
One  or  two  species  of  Clover  are  also  common  among  the  stones, 
and  the  Viscous  Senecio,  though  hardly  common,  is  found  among 
shingle.  This  latter  is  a  plant  not  unlike  the  Groundsel,  but 
taller  and  stronger  smelling.  The  accompanying  photograph  of  a 
newly  formed  shingle  beach,  kindly  supplied  by  Mr.  J.  H.  Priestley, 
is  full  of  interest.  It  represents  an  "open"  Plant  Association, 
the  dominant  species  of  which  is  the  Yellow  Horned  Poppy,  whilst 
the  Viscous  Senecio  (fruiting  in  the  photograph),  has  come  in 
along  railway  embankments  during  the  last  ten  to  fifteen  years. 
Observations  of  this  kind  help  one  to  realise  something  of  the  migra- 


FIG.  5. — Sea  Purslane  (Arenaria 
peploides). 


12 


THE  BOOK  OF  NATURE  STUDY 


tion  of  plants.  A  new  railway  line  presents  endless  opportunities. 
The  plants  coming  up  on  the  embankments  the  first  season  after 
the  line  has  been  laid  down  will  be  ousted  in  succeeding  seasons 
by  others,  and  it  is  interesting  to  trace  the  spread  of  any  particular 
species  along  the  line,  or  the  extermination  of  species  by  successful 
rivals  in  the  struggle  always  going  on  for  existence. 

CLIFF  VEGETATION. — The  vegetation  of  rocky  headlands 
depends  mainly  on  two  factors  :  the  nature  of  the  rock  and  the 
latitude.  Where  the  rock  is  hard  and  massive,  as  in  the  case  of 
granite,  Jhe  vegetation  is  scanty  and  far  less  luxuriant  than  it  is 
on  limestone  cliffs.  With  regard  to  latitude,  the  plants  which 
are  common  in  such  a  southern  county  as  Somerset  are  scarce 
off  the  coast  of  Northumberland,  and  are  not  found  beyond  the 
latitude  of  Edinburgh. 

The  following  table  shows  at  a  glance  the  principal  plants  of 
certain  typical  cliffs. 

VEGETATION  OF  CLIFFS 


CHARACTER  OF  ROCK. 


DOMINANT  SPECIES. 


SUB-DOMINANT. 


Rough  granite      .. 


Slates  and  quartzites 


Carboniferous  limestone 


Very  scanty  vegetation 


Sea  Samphire 
Sea  Aster 
Sea  Beet 


Sea  Samphire 


Chiefly  Heaths  and  Furze. 

Sea  Pink. 
Sea  Campion. 
Sea  Plantain. 
Scentless  Mayweed. 
Scurvy  Grass. 
Tree  Mallow. 
Sandspurry. 


Sea  Lavender  ^ 

Scentless  Mayweed  I  less 
Sea  Campion  |  abundant, 

Scurvy  Grass 


Slate  rocks  are  cut  by  the  action  of  the  waves  into  all  kinds  of 
shapes,  and  the  vegetation  in  the  cliffs  and  on  the  ledges  of  the 
rocks,  where  sand  or  other  soil  has  been  deposited,  is  sometimes 
luxuriant.  The  dominant  plant  is  usually  the  Sea  Samphire 
(Crithmum  maritimum).  This  has  a  short  zigzag  stem  and  very 
much  divided  leaves,  the  narrow  segments  of  which  stand  upright. 


MI  Mr.  J.  H.  Priestley,  University  College,  Bristol. 

HORNED  POPPY  IN  FRUIT  AND  FLOWER  ON  SHINGLE 


H.  Priestley ;  University  College,  Bristol. 

OPEN  ASSOCIATION  OF  A  NEWLY  FORMED  SHINGLE  BEACH 
Yellow-horned  Poppy  and  Viscous  Senecio  in  foreground 


CLIFF  VEGETATION 


It  belongs  to  the  Umbelliferse,  and  has  umbels  of  greenish-yellow 
flowers.  In  many  places  the  plant  is  not  as  abundant  as  it  would 
naturally  be,  for  at  one  time  it  was  very  much  used  as  a  condi- 
ment, owing  to  its  aromatic  properties.  In  some  places  the 
Golden  Samphire  is  found  in  the  neighbourhood  of  the  Sea  Sam- 
phire, but  this  is  a  very  much  rarer  plant,  only  resembling  its 
namesake  in  scent  and  taste.  The  Sea  Samphire  used  to  be  found, 
it  is  said,  as  far  north  as  the  islands  of  the  Firth  of  Forth,  but  it 
seems  now  to  be  quite  extinct.  The  Sea  Beet  belongs  to  the 
Goosefoot  tribe,  the  Cheno- 
podiaceae,  an  order  which  is 
characteristic  of  seashore 
vegetation,  and  comprises 
plants  with  fleshy  leaves  and 
small  greenish  flowers.  The 
Sea  Pink  (Armeria  vulgaris) 
is  of  all  cliff  plants  the  best 
known,  with  its  cushion  of 
green  leaves  and  heads  of 
pink  flowers.  It  is  alpine  in 
its  mode  of  growth,  and  is 
found  on  high  mountains, 
another  instance  of  the  simi- 
larity existing  between  the 
vegetation  of  high  hills  and 
seashores.  The  Sea  Campion 
is  very  like  the  Bladder  Cam- 
pion, which  belongs  to  inland 
situations.  Both  have  white  flowers  and  a  swollen  bladder-like 
calyx,  but  the  Sea  Campion  is  of  lower  growth  and  the  stems  are 
more  numerous  and  spreading ;  the  petals  too  are  broader.  There 
are  four  species  of  Sea  Lavender,  the  one  belonging  to  cliffs  is  the 
Statice  auriculcefolia ;  the  other  three  frequent  muddy  seashores. 
In  this  species  the  flowers  are  arranged  in  dense  spikes,  each  bearing 
two  rows  of  spikelets  with  the  flowers  all  turned  one  way.  Each 
spikelet  contains  two  or  three  flowers  enclosed  by  three  bracts.  The 
calyx  is  green,  the  upper  part  white,  contrasting  with  the  deep 
purple  of  the  petals.  There  are  five  stamens  and  five  long  curling 


FIG.  6. — Sea  Samphire  (Crithmum  maritimuni). 


THE  BOOK  OF  NATURE  STUDY 


white  styles.  The  Sea  Plantain  (Plantago  maritima}  differs  from  the 
Ribwort  Plantain  of  meadows  and  tennis  lawns  in  its  very  long, 
narrow,  fleshy  leaves.  It  is  also  found  on  high  mountains.  The 
Scurvy  Grass  (Cochlearia  officinalis)  is  a  Crucifer,  easily  recognised 
by  its  spoon-shaped  leaves  and  white  cruciform  flowers.  The 
Scentless  Mayweed  (Artemisia  maritima)  is  not  confined  to  rocky 
headlands,  but  grows  inland ;  when  growing  by  the  sea  it  is  more 

fleshy.  It  is  one  of  the  Composite, 
with  small  flower  heads,  each  con- 
taining three  to  five,  or  six,  florets. 

The  Tree  Mallow  (Lavatera  ar- 
borea)  is  a  very  local  plant.  It  is 
found  on  the  cliffs  of  Bray  Head. 
There  is  a  certain  resemblance  to  the 
Common  Mallow;  the  flowers  are 
about  the  same  size,  and  of  a  pale 
purple-red. 

The  Spurry  (Spergularia  rupestris) 
is  also  found  in  the  same  locality. 
This  variety  has  very  hairy  stipules, 
looking  almost  silvery.  The  Spurry 
is  closely  allied  to  the  Sandworts,  but 
differs  from  them  in  the  presence 
of  stipules.  Both  the  Sandwort  and 
the  Spurry  have  undivided  petals, 
whereas  most  of  the  genera  belong- 
ing to  the  Caryophyllaceae  have  the 
petals  very  deeply  divided.  This 
character  helps  in  the  identification  of  these  plants. 

The  following  description  of  the  vegetation  of  Brean  Down 
in  Somerset,  by  Mr.  Moss,  is  particularly  interesting,  as  it  shows 
the  transition  from  the  Crithmum  association  of  the  spray- washed 
rocks  to  the  Pasture  association  of  the  limestone  hills.  "  The  pro- 
montory is  formed  of  a  huge  block  of  carboniferous  lime-stone, 
rising  to  more  than  300  feet  above  the  sea-level.  Perpendicular 
rocks,  occupied  by  the  Crithmum  association,  rise  from  the  sea. 
At  the  south-western  extremity,  as  soon  as  the  rocks  cease  to  be 
vertical  but  yet  remain  steep,  the  rock  is  covered  by  a  thin 


FIG.  7.— Common  Thrift  (Armeria 

vulgaris). 


SEASHORE  PLANTS  ARE  SALT-LOVING  15 

marly  soil  impregnated  with  sodium  chloride.  Crithmum  has  here 
disappeared,  but  Armeria  (Sea  Thrift)  is  still  abundant.  As  the 
summit  is  reached,  Armeria  dies  out ;  and  the  remainder  of  the 
down  is  occupied  by  the  Limestone  associations/'  This  transi- 
tional stage  is  commonly  seen  in  the  downs  or  pastures  near  the 
sea.  Off  the  coast  of  Cornwall,  in  the  neighbourhood  of  Mullion 
and  the  Lizard,  where  the  Serpentine  rocks  form  bold  headlands, 
the  vegetation  consists  of  the  Wild  Squill,  the  Sea  Thrift,  the 
Lady's  Fingers  (Anihyllis  Vulneraria),  the  Scurvy  Grass,  and  several 
plants  of  the  Goosefoot  tribe.  These  are  not  found  on  the  cliffs, 
but  just  inland,  where  a  thin  layer  of  soil  has  been  deposited  on 
the  rocks.  One  of  the  most  characteristic  plants  is  the  Camo- 
mile, which  is  noted  in  a  history  of  Cornwall  written  in  1842. 
The  writer,  describing  the  neighbourhood  of  Liskeard,  says : 
"  Notwithstanding  the  rocks  of  granite  scattered  over  the  land, 
the  ground  was  rich  in  flowers.  Purple  and  gold  tints  prevailed 
in  the  heath  and  furze  blossoms.  Beds  of  Camomile  exhaled  an 
agreeable  odour,  covering  many  spots  on  the  hillside  upon  the 
way  to  the  town  of  Liskeard,  distant  only  two  or  three  miles." 
Similarly,  the  chalk  pastures  near  the  sea  in  such  a  county  as 
Sussex  will  be  characterised  by  maritime  plants. 

SEASHORE    PLANTS    ARE    SALT-LOVING. — Plants    adapted  for 
life  in  salt  marshes  and  by  the  seashore,  where  they  are  constantly 
washed  by  the  spray  of  the  waves,  differ  from  plants  living  away 
from  the  sea  in  the  percentage  of  common  salt  found  in  them. 
The  amount  of  salt  in  plants  growing  inland  is  not  usually  more 
than  5  per  cent.  ;   it  is  far  greater  in  seashore  plants. 
In  the  Sea  Thrift  it  varies  from  12*69  to  I5'I°  Per  cent. 
Sea  Aster  it  varies  from  43  to  49  per  cent. 
Sea  Artemisia  it  reaches  26-68  per  cent. 
Sandwort  (Arenaria  media)  it  reaches  36-55  per  cent. 
Sea  Plantain  it  reaches  45*53  per  cent. 

These  plants  seem  to  have  a  craving  for  salt,  so  much  so  that  if 
grown  in  ordinary  soil  they  extract  as  much  as  they  can  from  it. 
A  species  of  Scurvy  Grass  grown  on  sandstone,  when  analysed,  was 
found  to  have  41*70  per  cent,  of  salt ;  a  Sea  Rocket  grown  on  man- 
ured land  had  15*46,  and  the  Sea  Holly  as  much  as  19*30  in  its  ash. 


16  THE  BOOK  OF  NATURE  STUDY 

On  the  other  hand,  plants  which  do  not  tolerate  salt  die  if 
grown  in  soil  watered  with  a  solution  of  only  2  to  3  per  cent,  of 
common  salt.  This  is  true  of  all  plants  except  those  which  belong 
to  saline  habitats — Halophytes,  as  they  are  called, — and  of  a  few 
Non-Halophytes.  If  the  structure  of  these  salt-loving  Non- 
Halophytes  be  compared  with  that  of  Halophytes,  the  chief  re- 
semblances lie  in  the  arrangements  for  preventing  transpiration. 
They  have  either  a  very  thick  epidermis,  or  abundance  of  hairs, 
or  incurved  leaves  with  sunken  stomata,  or  a  reduced  leaf  surface. 
They  may  have  special  arrangements  for  the  storing  of  water,  and 
in  this  case  the  leaves  will  be  succulent.  Facts  of  this  kind  help 
to  explain  the  resemblance  that  undoubtedly  exists  between  the 
flora  of  high  hills  and  that  of  the  seashore.  It  is  true  that  there 
may  not  be  salt  in  the  air  blowing  over  hills  that  are  inland, 
but  this  situation  resembles  that  of  the  seashore  in  one  particular, 
namely,  in  the  irregularity  of  the  water  supply.  It  has  already 
been  noted  that  some  few  plants,  like  the  Sea  Thrift,  belong  to  both 
localities  ;  but  even  where  the  plants  are  not  the  same  there  is  a 
similarity  of  habit ;  they  are  plants  of  low  growth,  and  generally 
of  reduced  leaf  surface. 

The  colour  of  plants  by  the  sea  is  often  deeper  than  that  of  the 
same  species  growing  inland  in  valleys.  This  is  perhaps  due  to  the 
greater  number  of  hours  of  sunshine  which  seaside  places  have. 
It  is  well  known  that  the  colour  of  flowers  is  much  more  brilliant 
in  deserts,  at  high  latitudes  and  on  mountains  where  the  sunlight  is 
intense  and  continuous.  The  dark  blue  of  the  Squill  off  the  Cornish 
coast,  the  golden  yellow  of  the  Gorse,  the  pink  of  the  Sea  Thrift, 
seemed  deeper  than  that  of  inland  plants.  It  has  been  suggested 
that  the  blue-purple  colour  needs  the  greatest  amount  of  sunlight 
energy,  and  white  or  yellow  the  least.  From  this  point  of  view 
the  colours  of  the  plants  of  successive  seasons  might  be  observed  ; 
many  spring  flowers  are  certainly  yellow  or  white,  whilst  the 
bluish-purple  flowers  belong  to  June  and  July.  The  Daffodil, 
the  Celandine,  the  Colt's-foot,  the  Buttercups  are  yellow  ;  the 
Wood  Anemone,  the  Starwort,  the  Daisy  (Bellis)  are  white,  and 
these  belong  to  spring  ;  the  Cornflower,  the  Knapweed,  the  Self- 
heal,  the  Vetches,  and  many  another  are  bluish-purple,  and  flower 
in  the  summer  months  when  sunlight  is  not  only  intense  but  of 


PRACTICAL  WORK  17 

longest  duration.  There  are,  however,  many  exceptions,  and  the 
Violet  and  Bluebell  will  occur  to  every  one. 

Many  of  our  cultivated  plants  are  derived  from  Halophytes. 
The  Cabbage,  Cauliflower,  Broccoli,  Kale,  etc.,  are  cultivated 
varieties  of  the  Cabbage  Brassica  (Brassica  oleracea),  a  plant 
belonging  to  the  maritime  cliffs  of  the  Mediterranean  region. 
Thence  it  spread  to  the  coasts  of  northern  France  and  of 
southern  England,  and  is  now  found  on  many  of  the  cliffs  of 
our  islands,  in  some  cases  being  probably  an  "  escape  "  from 
cultivation.  The  Beet  and  Mangel  Wurzel  are  cultivated  varie- 
ties of  the  Wild  Beet  (Beta  maritima),  whose  natural  habitat  is 
the  muddy  seashore.  It  is  possible,  though  this  is  not  certainly 
known,  that  the  Radish  comes  from  a  seacoast  variety  of  the 
Wild  Radish,  i.e.  from  Raphanus  maritimum.  The  Horse  Radish 
(CoMearia  Armor acia)  is  not  an  indigenous  plant,  but  it  has 
become  naturalised  near  the  sea.  The  Carrot  is  probably  an 
original  native  of  the  seacoasts  of  Southern  Europe. 

The  Asparagus  has  its  natural  home  in  the  maritime  sands, 
or  sandy  plains,  of  Central  and  Western  Asia,  whence  it  spread 
to  the  Mediterranean  and  western  coasts  of  Europe.  At  the 
present  time  the  Wild  Asparagus  is  confined  in  Britain  to  the 
south-western  shores  of  England  and  to  one  or  two  counties  of 
Ireland. 

Lastly,  the  Coconut  tree  (Cocos  nucifera],  so  much  cultivated 
in  the  tropics,  grows  under  natural  conditions  only  on  the  saline 
soil  of  the  seashore. 

PRACTICAL  WORK. — On  sandy  seashores  note  the  effect  of 
the  wind.  If  the  most  prevalent  winds  are  those  that  blow 
towards  the  shore,  the  sand  is  heaped  up  into  dunes  ;  on  the 
other  hand,  if  the  predominant  winds  are  generally  off-shore, 
the  sand  is  continually  blown  back  into  the  sea  and  dunes  are 
not  formed. 

Look  for  "  ripple  marks,"  which  may  often  be  observed  on 
blown  sand.  The  sand  grains,  pushed  along  by  the  wind,  travel 
up  the  long  slopes  and  fall  over  the  steep  slopes.  Not  only  do 
the  particles  travel,  but  the  ridges  also  follow  each  other  more 
closely. 

VOL.  V. 2 


i8  THE  BOOK  OF  NATURE  STUDY 

On  sandy  seashores  the  following  belts  may  be  observed  :— 

1.  The   foreshore.     This   is   the   strip   between   the   ordinary 
high-tide  mark  and  low-tide  mark.     This  is  periodically  washed 
by  the  waves,  and  presents  alternately  terrestrial  and  aquatic 
conditions.      It   is   almost   constantly   exposed    to    the   spray ; 
evaporation  goes  on  rapidly,  and  the  temperature  is  constantly 
changing.     The  vegetation  is  in  consequence  limited,  consisting 
mostly  of  annuals  or  perennials  with  long  creeping  rhizomes. 

2.  The  midshore  comprises  the  belt  of  sand  between  ordinary 
high  tide  and  spring  tides. 

3.  The  upper  shore  is  the  strip  between  the  middle  beach 
and  the  sand-dunes,  if  these  are  formed.     There  is  more  humus 
in  the  soil,  because  there  is  more  vegetation.     The  spray  of  the 
waves  reaches  this  belt,  and  sand  is  constantly  being  blown  by 
on-shore  winds  from  the  midshore. 

4.  If  sand-dunes  are  formed  they  will  occur  to  landward  of 
the  upper  beach,  but  dunes  are  not  always  present.     The  sandy 
coast  may  rise  quite  gradually  without  any  sharp  line  of  separa- 
tion into  woodland  or  grassland.     The  formation  of  dunes  depends 
very  largely  on  the  direction  of  the  prevalent  wind. 

The  influence  of  the  wind  is  also  very  evident  in  the  distance 
to  which  the  spray  of  the  waves  may  be  carried,  making  the 
atmosphere  salt ;  this  is  very  well  seen  off  the  Cornish  coast,  where 
the  storms  are  often  very  violent.  The  branches  of  the  trees 
grow  with  an  inclination  towards  the  opposite  direction  from  that 
whence  the  wind  blows,  so  that  the  trees  seem  one-sided. 

5.  On  pebble  beaches  the  following  observations  are  suggested. 
The  larger  stones  are  heaped  up  on  the  higher  part  of  the 

beach,  forming  a  ridge,  the  smallest  pebbles  being  nearest  the 
sea. 

The  shape  of  the  pebbles  is  flat,  not  round,  as  in  rivers.  This 
indicates  that  they  have  been  pushed,  not  rolled  along. 

The  shingle  is  very  generally  arranged  in  festoons  or  scallops, 
sometimes  for  miles  in  length.  This  arrangement  has  been  attri- 
buted to  the  crossing  of  waves. 

The  effect  of  a  strong  on-shore  wind,  or  of  a  heavy  ground 
swell  on  the  shingle,  should  be  noted.  It  may  be  almost  entirely 
carried  away. 


OBSERVATIONS  OF  PLANT  FORMATIONS  19 

The  two  lines  of  seaweeds  are  clearly  seen  on  shingle  beaches  ; 
one  line  marks  the  high  water  at  the  last  spring-tide  ;  the  other 
is  the  high-water  line  of  the  last  tide. 

The  pebbles  which  have  seaweeds  attached  to  them  have 
probably  been  pulled  to  their  position  by  the  seaweeds. 

The  characteristics  of  plants  belonging  to  the  shingle  may  be 
ascertained  by  comparing  them  with  each  other. 

6.  In  observing  the  vegetation  on  cliffs  the  geological  character 
of  the  rock  should  be  ascertained  before  it  is  possible  to  compare 
one  flora  with  another.  It  is  easy  to  distinguish  stratified  from 
unstratified  rocks.  Granite  is  unstratified,  limestone  stratified. 
To  some  limited  extent  it  is  possible  to  recognise  rocks  by  their 
colour.  Chalk  is  white ;  unweathered  clay  is  blue,  but  the  action 
of  the  atmosphere  on  it  gives  it  a  yellow  tint,  and  the  effect  of 
burning  it  is  to  convert  it  into  a  brick-red.  The  old  red  sandstone 
is  red  in  colour,  but  red  may  also  denote  the  presence  of  iron  ;  it 
is  not  therefore  safe  to  depend  on  colour  alone.  Limestone  may 
be  detected  by  testing  with  a  strong  acid ;  a  piece  of  limestone  rock 
effervesces  when  hydrochloric  acid  is  poured  on  it.  A  geological 
map  of  a  district  will  give  the  geological  formations,  and  enable 
any  one  to  ascertain  the  nature  of  the  cliffs. 

The  plants  belonging  to  each  kind  of  cliff  can  only  be  a  matter 
of  gradual  observation.  Lists  should  be  made  of  the  plants  found 
at  different  seaside  places,  and  compared  with  each  other.  It  is 
impossible  to  generalise  until  a  great  many  places  have  been 
visited.  It  will  be  found  that  some  plants  are  common  to  all 
shores  ;  for  what  they  want  is  salt.  To  determine  in  any  particular 
case  whether  the  plant  requires  salt  or  not,  it  may  be  transplanted 
to  ordinary  garden  soil  and  watched.  If  it  thrives  without  any 
addition  of  salt  to  the  soil,  it  is  independent  of  salt ;  but  the 
majority  of  plants  growing  by  the  sea  will  not  flourish  in  an  inland 
garden  unless  the  soil  is  watered  with  a  solution  of  common  salt. 

OBSERVATIONS  OF  PLANT  FORMATIONS. — The  Plant  associations 
occurring  in  the  different  belts  of  the  shore  should  be  carefully 
noted  in  this  order  :  i.  Those  nearest  to  the  sea,  whether  on 
cliff  or  in  mud  or  on  sand.  These  are  open  associations.  2.  The 
Intermediate  associations,  which  may  be  two  or  three  in  number, 


20  THE  BOOK  OF  NATURE  STUDY 

and  are  on  the  landward  side  of  the  open  associations  nearest 
the  sea.  3.  The  Pasture  associations.  These  comprise  the 
plants  of — (a)  The  sand-dune  pasture  ;  (b)  the  salt  marsh  ;  (c)  the 
cliff.  In  all  these  pastures,  many  seashore  plants  will  be  found, 
for  the  spray  is  blown  by  the  wind  some  little  distance  inland 
and  the  plants  thus  get  the  salt  they  require. 

The  best  way  of  getting  an  idea  of  the  way  in  which  a  Plant 
formation  arises  is  to  watch  the  colonising  of  a  new  piece  of 
ground,  as,  for  instance,  a  railway  embankment  along  a  newly 
made  line.  The  first  plants  to  appear  should  be  recorded  ;  then 
their  destruction  by  other  plants.  The  gradual  migration  of 
plants  into  a  new  district  from  an  adjoining  area  is  an  observation 
full  of  interest. 

BIBLIOGRAPHY. — Lord  Avebury,  Scenery  of  England ;  Pethybridge,  "Vegeta- 
tion South  of  Dublin"  (Proceedings  of  the  Royal  Irish  Academy,  December  1905). 


CHAPTER   II 
AQUATIC  VEGETATION 

AQUATIC  vegetation  includes  both  salt  and  fresh  -  water 
forms.  These  two  groups  are  connected  by  the  plants, 
few  in  number,  belonging  to  brackish  water,  which  is  found  at 
the  mouths  of  rivers,  in  salt  marshes  that  are  gradually  being 
reclaimed,  and  in  inland  saline  lakes. 

The  flora  of  the  sea,  as  distinct  from  that  of  the  seashore 
already  described,  consists  mainly  of  Algae,  red,  green,  and  brown. 
In  fresh  water  the  predominant  plants  are  flowering,  and  only 
the  green  Algae  are  usually  found.  In  addition  to  flowering 
plants,  certain  Mosses,  some  few  Ferns,  and  other  Cryptogams 
occur  in  fresh  water,  but  are  absent  in  salt  water.  Among  Mosses 
may  be  mentioned  some  species  of  the  Fern  Moss  (Hypnum), 
and  the  Bog  or  Sphagnum :  The  Marsh  Fern  (Aspidium  Thelypteris) , 
the  Pillwort,  the  Quillwort,  and  the  Bog  Equisetum  are  instances 
of  fresh-water  Cryptogams ;  these  groups  are  entirely  absent 
from  the  sea  flora.  There  is  thus  a  striking  difference  in  fresh- 
water vegetation  compared  with  marine. 

The  flora  of  the  seashore,  with  the  exception  of  the  Seaweeds, 
is  mainly  terrestrial,  not  aquatic  ;  at  the  same  time,  it  is  profoundly 
influenced  by  the  sea,  for  the  sea  water  bathes  at  every  high 
tide  the  belt  of  vegetation  growing  on  the  shores,  and  the  spray, 
containing  salt,  falls  on  the  cliffs  and  gives  salt-loving  plants 
some  of  the  food  material  they  require.  The  effect  of  this  per- 
petual motion  of  the  waves  on  vegetation  may  be  compared  with 
the  effect  of  flowing  water  on  fresh-water  plants.  The  flora  of 
a  stagnant  pond  is  different  from  that  of  a  stream  or  river. 
Water  in  motion  makes  great  demands  on  the  resisting  power 
of  plants ;  in  structure  it  will  be  seen  that  they  have  far  more 
highly  developed  strengthening  tissue  than  those  which  merely  float 
on  the  surface  of  the  water. 


22  THE  BOOK  OF  NATURE  STUDY 

SUBMERGED  AQUATIC  PLANTS.  —  Some  aquatic  plants  live 
an  entirely  submerged  existence  :  they  even  flower,  and  are 
pollinated  under  water ;  they  form  seed,  which  is  dispersed  by 
water.  The  habit  of  life  of  such  plants  is  naturally  very  different 
from  that  of  land  plants,  and  also  from  those  aquatic  plants 
which  have  their  roots  and  some  of  their  leaves  in  water,  but 
otherwise  lead  a  terrestrial  existence.  In  some  ways  life  is  easier 
for  these  plants.  To  begin  with,  they  are  not  exposed  to  the 
rapid  changes  of  temperature  that  are  often  so  trying  to  plants 
that  live  under  atmospheric  conditions.  The  temperature  of 
water  is  more  uniform  ;  even  when  a  hard  frost  occurs,  the  sub- 
merged vegetation  is  protected,  for  the  ice  floats  to  the  top  and 
the  plants  are  sheltered  in  the  less  cold  water  flowing  beneath. 
Again,  they  are  not  exposed  to  the  frosts  of  early  spring,  which 
affect  the  blossoms  of  land  plants.  Then  the  whole  surface  of  a 
submerged  plant  is  able  to  absorb  water  and  the  substances 
dissolved  in  the  water,  and  this  facilitates  nutrition.  Plants  that 
live  an  entirely  submerged  existence  can  only  do  so  when  the 
water  is  sufficiently  clear  and  the  upper  surface  free  enough  of 
vegetation  to  allow  the  rays  of  light  to  penetrate.  The  Alga, 
Nitella,  for  instance,  is  found  in  Lake  Constance  at  a  depth  of 
about  thirty  yards  ;  in  more  turbid  waters  it  is  only  found  at  a 
depth  of  twelve  yards.  Below  a  depth  of  six  yards  it  is  unusual 
to  find  Flowering  Plants.  Some  of  these  submerged  plants  have 
more  or  less  upright  stems  with  cylindrical  leaves,  as  the  Quillwort 
and  the  Pillwort,  found  on  the  edges  of  lakes  in  clear  water  ; 
others  have  their  stems  parallel  to  the  surface  of  the  water  ;  they 
have  long  shoots,  adapted  for  floating  in  the  water,  e.g.,  certain 
species  of  Pondweed  (Potamogeton). 

Submerged  plants  are  usually  very  rapidly  propagated.  Many 
do  not  form  seed,  but  multiply  vegetatively.  A  twig  of  a  water 
plant,  broken  off  from  the  parent  stem,  is  able  to  lead  an  inde- 
pendent existence  and  form  a  new  plant.  It  is  in  this  way  that 
the  American  water-weed,  Elodea  canadensis,  has  spread  in  the  short 
space  of  sixty  years  through  Western  Europe  ;  it  was  first  observed 
in  Britain  in  1847,  in  Yorkshire,  Leicestershire,  and  near  Berwick 
and  Edinburgh  ;  now  it  is  found  in  most  ponds,  canals,  and  slow- 
flowing  streams. 


SUBMERGED  AQUATIC  PLANTS  23 

The  structure  of  an  aquatic  plant  differs  from  that  of  a  land 
plant  mainly  in  four  respects  :— 

1.  The  root-system  is  either  absent  or   very  much  reduced. 
The  main  function  of  the  root  is  to  fix  the  plant  in  the  bed  of  the 
stream,  or  on  some  stone  or  wood,  etc.  ;  it  is  not  engaged  to  any 
appreciable  extent  in  the  absorption  of  food  material  and  in  its 
conduction,  as  in  the  land  plant. 

2.  The  length  of  the  shoot  is  very  much  longer  in  a  water 
plant,  for  the  light  is  less  intense,  and  strong  light  retards  growth 
in  length.     A  transverse  section  of  the  stem  of  a  submerged  plant 
shows  a  comparatively  undeveloped  vascular  system.     There  is 
often  very  little  of  the  woody  tissue  which  helps  to  support  a  land 
plant  (Fig.  8). 

3.  The  cuticle  of  the  leaves  is  usually  thin,  or  even  absent ; 
the  whole  surface  is  engaged  in  absorption,   and  there  are  no 
stomata  in  submerged  plants,  although  they  are  naturally  present 
in  large  numbers  on  the  upper  surface  of  the  leaves  of  floating 
aquatic  plants. 

4.  Water  plants  have  air  spaces,  which  make  them  light. 
Submerged  aquatic  plants  may  be  arranged  in  the  following 

groups  : — 

(a)  Plants  fixed  to  stones  in  running  water.    These  include  some 
Mosses  and  a  few  tropical  plants  with  very  much  reduced  flowers. 

(b)  Rosette  plants,  rooted  in  the  ground,  generally  with  cylin- 
drical leaves.     These  belong  to  the  more  or  less  shallow  and  still 
waters  of  pools  and  lakes.     The  Cryptogamic  plants,   Pillwort 
and  Quillwort ;     and    the    flowering    plants,    Awlwort   and   the 
Water  Lobelia,  are  the  best  known  instances. 

(c)  Plants   rooted  in   the    soil,  or  free   swimming,  with  long 
flowing  shoots.     The  Slender  Naiad,  common  in  N.  America,  but 
found  only  in  a  few  places  in  Britain  ;   the  Hornwort,  a  free  swim- 
ming form,  belonging  to  pools,  and  adapted  for  pollination  in 
water,  and  the  Whorled  Milfoil  may  be  mentioned.     One  or  two 
other  plants,  as  the  Water  Soldier  (Stratiotes) ,  are  almost  entirely 
submerged,  and  in  general  habit  may  be  grouped  with  these. 

The  Pillwort  (Pilularia  globulifera),  is  not  a  flowering  plant, 
but  bears  spores  which,  unlike  those  of  the  fern,  are  of  two  sizes, 
large  and  small.  These  are  situated  in  bags  or  sporangia,  which 


24  THE  BOOK  OF  NATURE  STUDY 

are  contained  in  receptacles  that  look  like  little  pills  covered  with 
short  hairs  ;  hence  the  name  of  the  plant.  The  stem  creeps  under 
water,  rooting  at  every  node.  The  leaves  are  very  narrow, 
and  grow  upwards  ;  they  are  bright  green,  from  one  to  three 
inches  in  length,  and  rolled  inwards  at  the  top,  just  as  the  frond 
of  a  fern  is. 

The  Quillwort  (Isoetes  lacustris)  is  found  in  the  shallow  water 
by  the  edges  of  lakes,  as,  for  instance,  near  a  boathouse.  The 
easiest  way  of  getting  it  is  to  go  out  in  a  boat  a  yard  or  two,  to 
a  spot  where  its  dense,  dark  green  tufts  can  be  seen  through  the 
water,  and  then  to  pull  it  up  from  the  bed  of  the  lake.  The  root- 
stock  is  very  short  indeed,  and  bears  tufts  of  leaves.  The  spore- 
cases  are  enclosed  within  the  base  of  the  leaves,  and  the  spores  are 
of  two  sizes.  These  plants  with  two  sets  of  spores  form  a  link 
between  the  Ferns  on  the  one  hand  and  the  Flowering  Plants  on 
the  other.  The  small  spores  may  be  compared  with  the  pollen 
grains  of  the  flowering  plant,  and  the  large  spores  with  the  embryo- 
sac  of  the  ovule. 

The  Awlwort  (Subularia  aquatica)  also  belongs  to  the  shallow 
edges  of  ponds  and  lakes,  more  especially  to  alpine  districts.  It 
is  found  in  the  mountainous  regions  of  Scotland,  North-western 
England,  North  Wales,  and  Western  Ireland,  but  is  by  no  means 
common.  It  is  usually  entirely  submerged,  and  is  about  two 
inches  high.  The  leaves  are  radical,  the  flowers  have  minute 
white  petals.  The  pod  is  short  and  broad,  and  dehisces  from  the 
base  upwards,  as  in  the  Crucifers  generally. 

The  Naiads — the  nymphs  of  waters  and  springs  in  classical 
lore — are  slender  submerged  plants  with  linear  leaves  often 
crowded  into  clusters ;  the  flowers  are  small  and  sessile  in  their 
axils.  There  are  three  species  occasionally  found  in  this  country  : 
the  Slender  Naiad  in  Perthshire,  Skye,  and  Connemara  ;  the 
Holly-Leaved  Naiad,  found  only  in  Hickling  Broad,  Norfolk  ;  and 
the  Grassy  Naiad,  in  Lancashire.  This  fresh-water  genus  is  not 
nearly  as  common  as  the  marine  herb,  the  Grass- Wrack,  which 
belongs  to  the  same  order.  This  latter  has  a  creeping  stem, 
which  roots  in  the  sand  or  mud  and  is  found  most  abundantly  at 
or  below  low-water  mark.  The  Hornworts  have  no  roots,  the 
absorption  of  food  taking  place  entirely  from  the  surface  of  the 


SUBMERGED  AQUATIC  PLANTS  25 

leaves,  which  are  cut  up  into  thin,  linear  segments.  Pollination 
takes  place  under  water.  Each  staminate  flower  has  from  twelve 
to  twenty  anthers.  When  mature  they  contract  slightly,  and 
squeeze  the  pollen  into  the  water.  Being  of  the  same  specific 
gravity  as  the  water  it  does  not  sink,  but  is  almost  sure  to  reach 
the  stigma,  as  it  is  very  plentiful.  The  Hornwort  is  very  fairly 
common  in  pools,  or  slow  streams,  or  ditches  near  a  river,  or  on 
the  shallow  edges  of  lakes. 

The  Whorled  Milfoil  (Myriophyllum  verticillatum)  has  even  its 
flowers  in  water,  and  it  inhabits  deep,  clear  water.  The  Spiked 
Milfoil  creeps  and  roots  in  the  mud  under  water,  its  flowering 
spike  coming  above  the  surface.  Both  plants  have  very  fine 
whorled  leaves  ;  the  latter  is  the  more  common  species  in  Britain. 
In  general  appearance  the  Milfoils  are  not  unlike  the  Hornworts. 

The  Water  Soldier  (Stratiotes)  leads  during  the  greater  part  of 
its  life  a  submerged  existence.  During  the  winter  it  remains 
at  the  bottom  of  the  pond.  When  spring  comes  it  rises  to  the 
surface,  producing  fresh  leaves,  floating  roots,  and  as  the  summer 
comes  on,  flowers.  After  flowering  it  sinks  again,  to  mature  its 
fruits  and  seeds  and  to  develop  buds  for  the  production  of  young 
plants.  Towards  the  end  of  August  it  rises  again,  the  young 
plants  having  now  grown  up,  though  not  yet  as  large  as  the 
mother  plant.  For  a  time  the  parent  plant,  not  unlike  an  Amer- 
ican Aloe  in  appearance,  floats  on  the  surface  with  the  younger 
plants  attached  ;  then  the  connecting  stalks  die  and  decay,  each 
little  rosette  is  liberated  and  sinks  to  the  bottom,  and  all  hibernate 
till  the  following  April.  This  plant  is  common  in  the  fens  of  eastern 
England,  and  has  been  found  in  Lancashire  and  Cheshire. 

The  Water  Violet  (Hottonia  palustris)  has  the  creeping  habit 
of  entirely  submerged  plants,  the  flowering  stems  alone  coming 
out  of  the  water.  The  leaves  are  submerged  and  cut  up  into  fine 
segments,  as  those  of  water  plants  often  are  The  flower-stem 
bears  three  to  five  or  six  pale  purple  flowers.  This  plant  belongs 
to  the  Primulaceae,  and  frequents  central  and  eastern  England 
rather  than  the  west.  The  Water  Lobelia  (Lobelia  Dortmannii] 
is  another  aquatic  plant  that  flowers  above  water.  It  has  tufts 
of  hollow,  radical  leaves,  the  dense  green  carpet  of  which  can  be 
seen  through  the  clear  water  at  the  edge  of  a  lake.  The  leaves 


26  THE  BOOK  OF  NATURE  STUDY 

may  be  recognised  by  their  backward  curve,  and  by  being  com- 
posed of  two  tubes,  clearly  seen  when  the  leaf  is  cut  across. 
The  tall  flower-stem  arises  from  the  centre  of  the  rosette,  and 
lengthens  until  the  lowest  flower  is  well  above  the  water.  The 
flowers  are  pale  blue  ;  the  corolla  is  inclined  to  be  two-tipped, 
and  the  five  anthers  form  a  ring  round  the  style.  In  the  irregular 
corolla  and  the  union  of  the  anthers  the  Lobelia  differs  from  the 
other  members  of  the  Campanulaceae  with  which  it  is  associated. 

The  Pipewort  (Eriocaulon  septangulare)  grows  in  certain  dis- 
tricts with  the  Water  Lobelia.  The  root  stock  is  creeping,  and 
bears  on  its  under  surface  long,  white  fibrous  roots,  and  at  its 
extremity  grass-like  leaves.  The  flowering  stem  rises  above  the 
water,  and  is  usually  marked  with  seven  raised  lines,  whence  the 
name  "  septangulare."  The  flowers  are  mottled  white  and  black, 
and  arranged  in  a  dense  tuft,  those  in  the  centre  being  staminate, 
those  at  the  edge  pistillate.  The  distribution  of  the  plant  is 
limited  in  our  islands  to  the  Irish  lakes,  where  it  is  often  very 
abundant,  and  to  Skye  and  the  neighbouring  islands. 

THE  VEGETATION  OF  STILL  WATER  :  (a)  PONDS  AND  LAKES.— 
Ponds  are  abundant  in  pastures,  especially  if  there  is  a  substratum 
of  clay.  They  are  often  found  where  two  hedges  at  right  angles 
to  each  other  join,  and  on  the  shady  side  of  the  hedge,  for  in  such 
a  situation  the  cattle  can  get  shelter  from  the  noonday  sun  whilst 
quenching  their  thirst.  If  the  pond  is  not  under  the  shelter  of 
the  hedge  it  is  generally  planted  round  with  Hawthorn,  or  Willow, 
or  some  other  shrub,  gaps  being  left  for  the  animals  to  gain  easy 
access  to  the  water.  In  early  spring  a  pond  of  this  kind,  with 
the  Hawthorn  hedge  just  coming  into  bud,  perhaps  a  Willow 
bough  overhanging,  and  the  weeds  just  beginning  to  show  their 
green  leaves  on  the  surface  of  the  pond  side  by  side  with  some  of 
the  old  autumn  ones  that  still  float  on  it,  makes  a  restful  spot 
in  the  monotony  of  the  pasture.  The  Duckweed  may  cover 
the  whole  surface,  or  only  bits  here  and  there  near  the  edge  ; 
tangles  of  yellowish-green  Algae,  which  have  been  engaged  during 
the  winter  in  propagating  themselves  at  the  bottom  of  the  pond 
are  now  rising  towards  the  surface  to  get  as  much  light  as  possible 
for  the  new  growth  which  is  to  take  place  during  the  spring  and 


VEGETATION  OF  STILL  WATER  27 

summer.  Patches  of  the  Common  Reed  border  the  banks,  which 
may  be  almost  covered  with  the  glossy  yellow  blossoms  of  the 
Celandine  and  the  pale  lilac  of  the  Cuckoo-flower.  Even  as  early 
as  the  middle  of  April,  after  a  severe  winter,  the  Water  Crowfoot 
may  be  in  bloom,  its  white  flowers  above  the  water  making  it 
conspicuous.  This  plant  has  two  sets  of  leaves  :  those  in  the 
water  are  very  much  cut  up,  presenting  a  large  area  to  the  water  ; 
those  above  the  water  are  not  cut  up,  but  float  flat  and  dry  on 
the  surface,  enabling  the  plant  to  hold  its  flower-stems  well  up 
out  of  the  water.  After  flowering,  the  flower-stalk  curves  down- 
wards, and  the  fruit  ripens  beneath  the  water.  There  are  several 
varieties  of  this  species  :  some  are  found  in  running  streams, 
others  in  deep  still  waters ;  it 
varies  very  much  with  the  situa- 
tion in  which  it  is  growing. 

In  summer  most  ponds  have 
some  species  of  Potamogeton  or 
Pondweed.  There  are  a  large 
number  of  these  Pondweeds,  which 
mostly  resemble  each  other  in 
having  a  root-stock  that  creeps  in 
the  mud,  very  narrow  leaves  in 
the  water,  and  usually  much  FIG.  8.~Stem  of  Potamog^  (transveisc 

broader   leaves  that    float    On    the          section).      *,    Epidermis ;     c,    cortical 

surface.  The  chief  variation  is  in  ^^  with  air-spaces ;  «/,  conducting 
the  leaves  :  the  majority  of  species 

have  both  submerged  and  floating  leaves  ;  in  others  the  broad 
leaves  are  borne  under  the  water,  and  occasionally  the  floating 
leaves  are  not  broad,  but  narrow.  A  comparison  of  the 
plants  found  in  still  water  undoubtedly  shows  that  their  habit 
is  to  float ;  not  only  the  leaves,  but  the  stems  can  float. 
A  transverse  section  of  a  Potamogeton  (Fig.  8)  shows  the 
structure  of  a  stem  adapted  for  floating.  The  cortex  has  very 
large  intercellular  spaces,  filled  with  air ;  these  make  the 
plant  very  light,  enabling  it  to  float,  and  they  also  serve  to 
convey  the  air  to  the  lower  parts  of  the  stem  growing  in  the 
deeper  water,  or  creeping  in  the  mud.  The  woody  tissues 
which  support  land  plants  are  in  these  water  plants  very  much 


28  THE  BOOK  OF  NATURE  STUDY 

reduced,  and  are  placed  in  the  centre — not  midway,  as  in  land 
plants — for  the  weight  of  the  plant  as  it  floats  is  supported  by 
the  water,  and  the  strain  in  still  water  is  very  slight.  The  structure 
of  the  leaf  is  also  adapted  to  the  floating  habit.  Leaves  of  this 
kind  are  usually  round,  or  entire,  or  very  slightly  lobed  ;  they 
bear  stomates  on  their  upper  surface,  which  is  usually  very  glossy 
owing  to  the  wax  that  covers  it  and  prevents  it  getting  wet. 
Kerner  gives  11,500,000  stomates  for  the  average-sized  leaf  of  the 
Water  Lily. 

The  water  of  ponds,  is,  as  a  rule,  shallow  enough  to  be  pene- 
trated by  the  rays  of  light  throughout  its  whole  extent ;  in  fresh- 
water lakes  the  depth  may  be  considerable,  and  in  these,  three 
regions  of  illumination  are  distinguished  :— 

1.  The  bright  region,  in  which  the  intensity  of  light  is  sufficient 
for  the  development  of  flowering  plants. 

2.  The  dim  region,  where  most  flowering  plants  can  hardly 
exist.     Below  a  depth  of  two  yards  the  green  alga  Chara  forms  an 
important  part  of  the  vegetation ;  below  seven  or  eight  yards 
Nitella  takes  the  place  of  Chara,  and  a  few  Mosses  may  be  found 
with  it. 

3.  The  dark  region,  where  vegetation  is  very  scanty  indeed, 
and  is  practically  confined  to  plants  without  green  leaves. 

It  must  be  remembered  that  the  depth  to  which  light  pene- 
trates water  depends  on  the  clearness  of  the  water,  and  that  varies 
with  locality  and  season.  In  Lake  Geneva,  in  September,  a 
photographic  plate  became  slightly  dark  at  a  depth  of  170  metres, 
and  very  dark  at  120  ;  whilst  in  April,  even  at  a  depth  of  250, 
light  was  not  altogether  absent. 

The  following  regular  succession  of  plants  has  been  observed 
off  Scotch  lochs  : — 

(a)  Marsh  plants,  such  as  Sedges  and  the  Lesser  Spearwort, 
mix  with   the  Meadow  Clovers  and   Grasses,  where  the  soil  is 
water-logged. 

(b)  A  narrow  belt  of  Rushes. 

(c)  Iris  or  Sweet  Flag,  where  the  water  is  less  than  eighteen  inches. 

(d)  Reeds,  such  as  Scirpus,  from  two  to  four  feet. 

(e)  Water  Lilies,  the  rhizomes  of  which  may  be  at  a  depth  of 
nine  feet. 


VEGETATION  OF  STILL  WATER  29 

(/)  Pondweeds,  chiefly  Potamogeton  natans. 

(b)  Open  water,  with  Diatoms  and  other  Algae,  chiefly  Chara 
and  Nitella. 

Of  these,  the  Reed  association  is  the  one  that  varies  the  most. 
With  the  Scirpus  lacustris,  sometimes  the  dominant  form,  may 
be  associated  the  Common  Reed,  Phragmites  communis  (a  true 
grass),  or  a  species  of  Equisetum  (E.  limosum).  The  Common 
Reed,  with  its  horizontal  stem  and  vertical  branches,  is  of  great 
service  in  enabling  the  plants  to  get  out  from  the  edge  into  more 
open  water.  Other  plants  commonly  found  with  the  Reed 
association  are  the  Flowering  Rush,  the  Water  Plantain,  and  the 
Arrowhead — plants  which  also  belong  to  running  water.  With 
regard  to  the  Water-Lily  association,  it  is  found  in  Switzerland 
and  Germany  that  the  Yellow  Water  Lily  succeeds  the  White. 
The  Quillwort  may  also  be  found  in  this  belt.  It  is  interesting 
to  note  that  the  Duckweed,  characteristic  of  ponds  is  not  found 
in  lakes. 

Fresh-water  lakes,  to  which  the  sea  may  have  had  access  in 
past  geological  ages,  often  have  a  flora  of  peculiar  interest.  The 
shores  of  Lough  Neagh  yield  the  following  maritime  plants  :  the 
Sea  Scirpus,  Field  Cerastium,  Stork's  Bill,  Hare's-foot  Clover, 
and  Sandspurry.  Many  water  plants,  such  as  the  Awlwort, 
the  Water  Parsnip,  the  Elongated  Carex,  used  to  be  found  there, 
but  seem  to  have  disappeared  with  the  lowering  of  the  level  of 
the  lake. 

Many  of  the  plants  mentioned  as  characteristic  of  the  edges 
of  lakes  are  also  found  in  very  gently  flowing  water  in  canals 
and  in  back  waters.  The  Creeping  Scirpus,  the  Water  Plantain, 
the  Arrowhead,  Sweet  Flag,  the  Flowering  Rush  are  instances.  It 
would  be  easy  to  make  records  of  the  plants  found  by  the  side 
of  any  of  the  numerous  canals  which  intersect  the  country  ;  they 
should  be  visited  early  in  the  summer,  before  vegetation  begins 
to  decay,  as  they  are  not  then  very  pleasant. 

(b)  BOGS  AND  FENS. — It   is  not  always  easy  to  distinguish  a 

i  bog  from  a  marsh,  the  transition  from  one  to  the  other  being 

sometimes    very    gradual.      To    most   minds    the    term    "  bog " 

.  recalls  soaky,  peaty  ground  in  the  midst  of  a  heather  moor ;  but 


30  THE  BOOK  OF  NATURE  STUDY 

bogs  may  be  formed  on  other  soil  than  peat,  provided  it  is  a  soil 
that  does  not  allow  the  water  to  percolate  through,  as  on  Fuller's 
Earth.  The  character  of  the  vegetation  in  marshy  and  boggy 
ground  depends  on  whether  the  soil  is  peaty  and  the  water  rich 
in  mineral  substances  such  as  lime.  The  water  of  peat  bogs  is 
poor  in  lime,  and  the  plants  are  mostly  slow  growing  and 
dwarf y.  A  marsh  usually  has  water  rich  in  mineral  substances, 
and  plants  grow  rapidly.  Bogs  may  be  found  at  any  height, 
from  a  few  feet  above  the  sea  level  to  several  thousands  ;  but  a 
marsh  is  more  usually  on  low  ground,  on  the  outer  margins  of 
ponds  and  streams  and  in  hollows  where  drainage  is  deficient ; 
it  may  even  mark  the  position  of  a  former  pond  which  has  been 
filled  up  and  drained.  Plants  living  on  marshy  ground  will  be 
superseded  by  other  species  if  the  ground  is  drained.  This  is 
very  well  seen  in  deserted  brick  ponds.  As  the  water  gets  less 
and  less,  different  plants  begin  to  appear  on  the  sides,  which  are 
drier  than  they  were  when  the  pond  was  fuller ;  by  degrees 
plants  which  do  not  care  for  a  moist  soil  establish  themselves,  and 
in  a  few  years  the  vegetation  may  seem  almost  xerophytic.  The 
following  plants  were  gathered  on  the  slopes  of  a  deserted  brick 
pond  in  April :  Colt's-foot,  Groundsel,  Rockcress,  Stinging  Nettles, 
Purple  Deadnettle.  There  was  very  little  water  left  in  the  pond, 
and  only  some  algae  in  it.  What  time  has  elapsed  since  that 
pond  was  first  deserted  is  not  certainly  known,  probably  at  least 
ten  years. 

Insectivorous  plants  are  characteristic  of  peat-bogs ;  these 
plants  get  the  nitrogen  necessary  for  their  life  from  the  insects 
on  which  they  feed.  A  great  many  experiments  were  tried 
by  Darwin,  in  order  to  ascertain  whether  these  plants  would 
absorb  non-nitrogenous  fluids.  He  placed  drops  of  distilled 
water  on  the  leaves  of  Sundew,  but  the  tentacles  which  are  situated 
on  the  edge  of  the  leaf  remained  motionless  ;  then  he  tried  solu- 
tions of  gum  arabic,  sugar,  starch,  alcohol,  even  tea,  but  in  experi- 
ments on  sixty-one  leaves  no  effect  was  produced  ;  the  tentacles 
would  not  respond  to  the  stimulus  of  non-nitrogenous  liquids. 
The  case  was  very  different  with  nitrogenous  foods,  such  as  milk, 
albumen  fresh  from  a  hen's  egg,  saliva,  isinglass,  etc.  In  the  case 
of  milk  he  found  that  the  tentacles  took  forty-five  minutes  to 


VEGETATION  OF  STILL  WATER  31 

become  inflected  ;  that  in  two  cases  the  blades  of  the  leaves  were 
so  much  curved  inwards  that  they  formed  little  cups  enclosing 
the  drops  of  milk  ;  that  the  leaves  expanded  on  the  third  day. 
Altogether,  Darwin  experimented  with  nitrogenous  fluids  on 
sixty-four  leaves,  and  found  that  sixty-three  responded.  Care 
has  to  be  taken  to  select  young  and  active  leaves,  as  old  ones 
have  not  sufficient  power  of  response.  These  experiments  cer- 
tainly seemed  to  show  that  non-nitrogenous  matter  did  not 
stimulate  the  leaves  of  the  Sundew  ;  to  place  the  matter  beyond 
a  doubt,  Darwin  tested  the  same  leaves  with  bits  of  meat,  and 
found  they  did  respond,  though  not  so  readily  as  fresh  leaves, 
for  their  powers  had  been  somewhat  impaired  owing  to  the  experi- 
ments with  non-nitrogenous  material.  Other  experiments  were 
performed  to  ascertain  the  nature  of  the  process.  Darwin 
found  that  the  glands  in  the  knob  of  the  tentacles  of  Sundew 
have  the  power  of  secreting  a  ferment  analogous  to  the  pepsin 
contained  in  the  gastric  juice  of  animals ;  this  ferment  in  the 
presence  of  an  acid  dissolves  nitrogenous  compounds.  The 
length  of  time  during  which  the  tentacles  remain  inflected  depends 
partly  on  the  quantity  of  the  substance  given ;  they  remained 
inflected  longer  over  large  bits  of  meat  than  over  small  ones, 
and  only  the  tentacles  on  the  same  side  as  that  on  which  the 
meat  was  placed  bent  in,  whilst  those  on  the  opposite  side 
remained  distended.  To  repeat  some  of  Darwin's  experiments 
as  recorded  in  his  book  on  Insectivorous  Plants  would  give  a 
far  better  idea  than  any  description  of  the  response  of  these  plants 
to  the  stimulus  of  nitrogenous  objects. 

Insectivorous  plants  may  be  arranged  in  two  groups : 
(i)  Those  that  catch  insects  by  means  of  traps  ;  (2)  those  that 
perform  movements  in  the  capture  of  their  prey.  To  the  first  be- 
long the  Bladderwort ;  to  the  second,  the  Sundew  and  Butterwort. 
There  are  three  fairly  common  species  of  Bladderwort.  The  most 
common  is  the  Utricularia  vulgaris,  which  is  found  in  deep  pools. 
It  has  not  true  roots,  but  root-like  floating  branches,  sometimes 
nearly  a  foot  long.  The  leaves  are  very  much  divided,  and  bear 
bladders.  The  flower-stem  is  six  to  eight  inches  high,  bearing 
a  few  large  yellow  flowers,  which  are  generally  over  by  the  end 
of  August,  or  even  earlier.  The  smallest  Bladderwort  (Utri- 


THE  BOOK  OF  NATURE  STUDY 


cularia  minor)  has  much  smaller  floating  branches,  not  more 
than  three  inches  long,  and  the  leaves  have  few  bladders  ;  the 
flowers  are  pale  yellow  and  much  smaller.  This  is  a  commoner 
species  than  the  other.  The  Intermediate  Bladderwort  (U. 
intermedia)  differs  from  these  two  species  in  the  fact  that  the 
bladders  and  leaves  are  borne  on  different  branches  ;  it  is  a  rarer 
species  than  the  other  two,  and  does  not  often  blossom.  The 
bladders  are  modified  leaflets,  each  attached  by  a  little  stalk  to 
the  submerged  floating  stem.  At  the  upper  end  of  the  sac-like 
bladder  there  is  a  small  opening,  around  which  are  a  number  of 
stout  forked  bristles  (Fig.  9).  The  opening  is  closed  by  a  valve, 

which  opens  inwards,  and  shuts  like  a  spring 
door  against  the  thickened  rim  of  the  aper- 
ture. By  means  of  these  bladders  the  plant 
captures  an  immense  number  of  small  aquatic 
animals.  Darwin  found  four,  five,  eight,  or 
even  ten,  minute  crustaceans  in  the  bladders 
he  examined.  What  attracts  these  animals 
to  the  bladder  is  not  positively  known ;  they 
may  be  seeking  a  hiding-place  from  larger 
animals,  and  the  bladder  being  transparent 
may  attract  them.  They  push  against  the 
valve,  which  yields  at  once,  then  as  soon  as 

FIG.      9.  —  Bladderwort     ,,.,,_  -,      n 

(Utricuiaria\   A  single   the  animal  has  entered  closes  again,  so  that 

flower  and  bladder  on   it  cannot  escape.     The  bladder  is  lined  with 

the  right  CC-QS  a(}apted  for  absorbing  the  products  of 

the  decaying  body,  but  there  does  not  appear  to  be  any  special 

digestive  juice,  as  in  the  Sundew. 

It  is  easy  to  recognise  the  Sundew  from  the  long  bright  red 
hairs,  or  tentacles,  on  the  edges  of  the  leaves.  The  three  species 
may  be  distinguished  from  each  other  by  the  following  characters. 
The  Round-leaved  Sundew  has  round  leaves,  lying  almost  flat  on 
the  ground  ;  this  is  the  most  common  species.  The  Long-leaved 
Sundew  (Drosera  anglica)  has  upright  leaves,  about  six  times  as 
long  as  they  are  broad,  and  a  flowering  stem  which  rises  erect 
from  the  centre  of  the  leaves.  The  Intermediate  Sundew  may 
be  recognised  by  the  flowering  stem,  which  is  horizontal  in  its 
lower  part,  then  erect.  These  plants  perform  movements  by 


VEGETATION  OF  STILL  WATER  33 

which  the  insect  is  caught.  The  tentacles,  as  already  described, 
bend  over,  the  leaf  curves  over,  and  the  animal  is  digested  by  the 
juice  secreted  by  the  gland  of  the 
tentacle. 

Another  insectivorous  plant  that 
performs  movements  by  which  in- 
sects are  entrapped  is  the  Butter- 
wort,  which  thrives  on  damp  spots, 
the  neighbourhood  of  springs,  banks 
of  brooks,  peat-bogs.  Very  often 
it  is  found  in  company  with  the 
Sundew.  The  Butterwort  has  its 
leaves  to  some  extent  permanently 
incurved ;  insects  washed  down  by 
the  rain  are  thus  caught  by  these 
incurved  margins.  The  leaves  are 
covered  with  two  sets  of  glands, 
which  secrete  mucilage  and  an  acid 
digestive  fluid.  It  has  been  calcu- 
lated that  there  are  25,000  muci- 
lage secreting  glands  on  a  square 

,.  P  -,->  ir        FIG.  10. — Sundew  (Drosera  anglica). 

centimetre   of    a   Butterwort  leaf, 

and  that  six  to  nine  leaves  will  have  about  half  a  million  of  them. 
The  body  of  the  insect  is  digested  by  the  acid  juice.  It  has  been 
found  by  experience  that  inorganic  material,  such  as  grains  of 
sand,  do  not  stimulate  the  secretion  of  either  the  mucilage  or  the 
digestive  acid.  The  Butterwort  bears  slender  flower  stems,  each 
with  a  single  two-lipped  purple  flower,  which  is  spurred.  The 
Butterwort  bears  transplanting  very  well,  and  will  flower  in  a 
window  box,  provided  it  is  on  the  shady  side  of  the  house  and 
that  the  soil  is  kept  moist  with  bog-moss.  The  number  of  insects 
that  these  plants  will  catch  is  almost  incredible.  Darwin  relates 
that  142  insects  were  found  on  thirty-two  leaves,  which  had  also 
entrapped  leaves  of  such  plants  as  Heather,  Sedges,  and  Rushes. 
The  insects  included  small  flies,  some  ants,  a  few  small  beetles, 
spiders,  and  even  small  moths. 

Another  feature  of  most  bog  plants  is  their  xerophytic  char- 
acter, perhaps  owing  to  the  fact  that  the   peat-water   can   be 

VOL.  V. — 3 


34  THE  BOOK  OF  NATURE  STUDY 

tolerated  by  plants  of  this  habit.  The  Cotton  Grass,  several 
species  of  Carex,  the  different  heath-like  plants  found  in 
the  drier  parts  of  peaty  bogs  are  instances  of  this.  It  is 
in  the  Lake  district  and  in  the  Scotch  Highlands  that  bog 
plants  are  seen  in  their  perfection.  One  gets  to  associate  certain 
flowers  with  the  Wordsworth  country,  as,  for  instance,  the  Bog 
Asphodel  with  Blea  Tarn  on  the  Langdale  Pikes.  The  Grass  of 
Parnassus,  Bog  Orchids,  the  Bog  Myrtle,  Bog  Cinquefoil,  Buck- 
bean,  Bog  Pimpernel  are  all  characteristic  of  peat-bogs.  The 
Grass  of  Parnassus  is  in  flower  in  August.  When  in  bud  the  flower 
looks  like  a  round  ball,  the  white  petals  of  which  may  be  seen 
through  the  green  calyx.  There  are  five  stamens  with  perfect 
anthers,  and  five  bearing  instead  of  anthers  a  tuft  of  filaments  with 
yellow  glands  that  answer  to  nectaries,  though  they  secrete  no 
nectar.  The  pollination  of  the  plant  should  be  watched.  The 
anthers  liberate  this  pollen  one  at  a  time  ;  if  an  insect  in  search 
of  honey  alights  in  the  middle  of  the  flower  it  is  certain  to 
brush  itself  against  the  anther  which  has  dehisced  that  very  day. 
If,  however,  an  insect  crawls  in  from  the  edge  of  the  petals,  it 
has  to  climb  over  these  yellow  knobs  to  get  the  honey,  and  in  so 
doing  must  almost  reach  the  centre  of  the  flower,  and  thus  it 
comes  in  contact  with  the  anther.  Thus  the  Grass  of  Parnassus 
can  be  pollinated  by  different  insect  visitors,  by  those  which  alight 
from  above  as  well  as  by  those  which  crawl  in  from  the  edges. 
The  greater  the  number  of  insect  visitors,  the  more  certainty  is 
there  of  pollination  taking  place  in  seasons,  in  which  insects  are 
few.  The  Bog  Myrtle  (Myrica  Gale)  grows  to  a  height  of  three 
or  four  feet ;  the  leaves  are  fragrant  when  bruised.  Generally 
the  stamens  are  on  one  plant,  the  carpels  on  another.  This 
shrub  is  wind-pollinated. 

In  exploring  a  bog  it  will  soon  be  noticed  that  some  plants 
are  found  in  the  little  pools  formed  on  the  surface  of  the  peat ; 
others  cling  to  the  sides  of  the  pools,  others  again  belong  to  the 
drier  parts.  The  Buckbean  is  not  confined  to  bogs,  but  is  also 
found  in  shallow  ponds,  it  belongs  to  the  wetter  soil  of  the  bog  ; 
it  has  densely  matted  roots  which  creep  along  in  the  black  peat, 
or  in  the  mud  of  a  pond.  Its  flowers  are  pure  white  within,  but 
fringed  with  pink  on  the  outside,  the  petals  are  fringed  with  white 


Photo  from  Mr.  J.  H.  Priestley,  University  College,  Bristol. 

DITCH  IN  A  PEAT  MOOR,  COMPLETELY  FILLED  WITH  BUR-REED 
(Sparganium  ramosum) 


VEGETATION  OF  STILL  WATER 


35 


filaments,  which  form  a  contrast  to  the  red  stamens  within.  There 
are  long-styled  and  short-styled  forms,  as  in  the  Primrose,  to  ensure 
cross-pollination,  and  the  fringes  on  the  petals  keep  out  insects 
that  would  be  too  small  to  pollinate  the  flower.  In  the  month  of 
August  the  Buckbean  is  in  fruit,  and  the  flowering  spikes  stand 
some  six  inches  or  more  erect  above  the  surface  of  the  bog,  bearing 
brown,  withered-looking  capsules.  The  name  Buckbean  is  due  to 
the  leaves  bearing  some  resemblance  to  those  of  the  Broad  Bean. 

The  Bog  Pimpernel  clings  to  the  sides  of  the  pools.  It  has 
very  delicate  leaves  and  pale  pink  flowers.  The  stamens  are 
joined  together  by  the  bases  of  the  filaments,  and  are  densely 
clothed  with  long  white  hairs  to  protect 
themselves  from  small  insects.  The 
Marsh  Pennywort  often  covers  the 
boggy  ground  with  its  large  green  leaves 
in  the  shape  of  a  penny.  It  is  one  of 
the  smallest  of  the  Umbelliferae,  with 
very  minute  greenish  flowers  tinged 
with  pink. 

The  Bog  Cinquefoil  (Potentilla  Corn- 
arum)  is  often  softly  hairy  on  both 
sides,  a  xerophytic  character.  The 
outer  side  of  the  calyx  is  brightly 
coloured, — in  fact,  the  whole  plant  is 
often  a  bluish-purple,  and  the  stem  is, 
as  occurs  frequently  among  bog  plants, 
creeping.  Among  Bog  Orchids  may  be 
mentioned  the  Bog  Malaxis,  which  flowers  late  in  summer  and 
is  not  easy  to  find.  It  inhabits  spongy  bogs,  and  is  only  three 
or  four  inches  high.  From  the  root-stock  a  small  bulb  is  pro- 
duced out  of  the  ground,  and  there  are  three  or  four  radical 
leaves.  The  flowers  are  very  small,  of  a  greenish-yellow.  The 
"  labellum  "  is  short,  and  arches  over  the  stamen  and  carpel ;  the 
place  usually  occupied  by  the  labellum  is  taken  by  the  central 
sepal,  which  acts  as  a  platform  for  insects. 

The  Plant  associations  most  common  in  bogs  are  : — 

i.  The  Sphagnum  association,  in  this  the  Bog  Moss  is  the 
dominant  species. 


FIG.  ii.— Bog  Pimpernel 
(Anagallis  tenella). 


THE  BOOK  OF  NATURE  STUDY 


2.  The  Cotton  Grass  or  Eriophorum  association,  with  the 
Cotton  Grass  dominant. 

Both  these  have  already  been  fully 
treated  in  connection  with  the  vegeta- 
tion of  moorlands  (Vol.  IV.) 

3.  The  Juncus  Sphagnum  associa- 
tion. This  is  found  at  an  altitude  of 
nearly  2000  feet.  The  Sphagnum 
and  the  Hair  Moss  (Polytrichum)  form 
a  dense  undergrowth,  sometimes  a 
foot  in  height,  whilst  the  Common 
Rush  (Juncus  communis)  and  some- 
times other  species  form  a  thick 
overgrowth.  In  this  association  the 
Rushes  and  the  Mosses  are  equally 
dominant ;  it  is  not  developed  on 
thick  peat,  but  rather  in  soil  which 
contains  plenty  of  humus  material 
and  water  which  is  not  stagnant  but 
slowly  moving.  The  sub-dominant 
plants  are  :  Lesser  Spearwort,  Ling, 
Red  Rattle,  Sheep's  Sorrel,  some 
Carices,  Bedstraws,  and  Grasses. 
Sometimes  the  insectivorous  plants, 
Sundew  and  Butterwort,  occur ;  it 
depends,  in  part  at  any  rate,  on  how 
water-logged  the  ground  is. 

The  vegetation  of  the  Fen  coun- 
try affords  considerable  material 
for  observations  of  all  kinds.  In 
no  part  of  England  has  the  influence 
of  man  been  greater.  Hardly  any  of 
the  original  fen  remains  untouched; 
only  at  Wicken  is  it  possible  to 
see  the  flora  that  used  to  cover 
the  whole  district.  Nearly  all  the 

FIG.  12.— Lesser  Spearwort  Fen  country  has  been  drained  and 
(Ranunculus  Fiammuia}.  reduced  to  cultivation,  each  field,  be 


VEGETATION  OF  STILL  WATER 


it  potato  or  corn,  now  has  the  weeds 
that  belong  to  cultivated  areas,  The 
introduction  of  roads,  usually  mended 
with  chalk,  accounts  for  another  set  of 
plants  not  natural  to  the  Fen  region. 
Apart  from  the  plants  due  to  the  in- 
fluence of  man,  the  Fen  district  offers  a 
great  variety  of  vegetation,  for  it  is 
possible  to  trace  at  least  three  distinct 
deposits  in  this  region.  There  is  the 
gravel  brought  down  by  the  rivers ;  the 
peat  formed  by  the  flooding  of  the  dis- 
trict and  accumulation  of  vegetable 
matter,  now  reaching  a  thickness  of 
twenty  feet  in  parts ;  the  silt  deposited 
by  the  sea,  as  it  burst  in  behind  the 
Alluvium,  is  laid  down  in  considerable 
quantity  over  the  level  ground  on  which 
a  river  spreads  when  in  flood,  for  the 
water  in  spreading  out  on  the  plain 
loses  velocity  and  consequently  power 
of  transport,  and  the  mud,  soil,  etc., 
held  in  suspension  falls  on  the  plain. 
This  must  have  happened  over  and 
over  again  in  the  Fen  country,  and 
accounts  for  the  presence  of  gravel  and 
peat  in  this  region ;  the  villages  usually 
stand  on  gravel  beds,  which  are  no- 
where higher  than  56  feet,  and  slope 
down  in  some  parts  under  the  peat  and 
silt.  The  peat  has  ceased  to  grow,  pro- 
bably because  the  climate  is  getting 
drier  ;  it  occupies  a  larger  area  of  fen- 
land  than  the  gravel,  and  is  charac- 
terised by  an  almost  even  surface  and 
the  absence  of  hedges.  Ditches  lined 
with  the  Common  Reed — a  true  Grass 
—Phragmites  communis,  take  their 


FIG.  13. — Common  Reed 
(Phragmites  communis}. 


38  THE  BOOK  OF  NATURE  STUDY 

place.  It  is  in  the  peat  area  that  the  characteristic  Fen  plants 
are  found ;  whilst  in  the  silt  land  there  will  be  plants  of  a  more 
or  less  maritime  character.  The  Fen  plants  should  be  looked 
for  near  the  ditches.  The  dominant  species  will  probably  be 
found  to  be  the  Sedge,  Cladium  germanicum  ;  but  this  is  some- 
times ousted  by  one  of  two  Grasses,  Molinia  ccerulea,  which,  as 
already  noticed,  is  characteristic  of  wet  moors,  or  Phragmites 
communis.  Where  the  ground  is  subject  to  frequent  flooding 
the  Phragmites  ousts  both  the  Molinia  and  the  Cladium  ;  on  the 
other  hand,  if  flooding  occurs  but  rarely,  the  Cladium  drives  out 
the  Phragmites.  Other  plants  belonging  to  what  may  be  called 
a  Phragmites,  or  a  Cladium  association,  are  :  The  Yellow  Meadow 
Rue,  the  Marsh  Marigold,  the  Larger  Convolvulus,  and  the  Marsh 
Pea.  The  Yellow  Meadow  Rue  grows  from  two  to  four  feet  high, 
and  has,  like  the  Ranunculacese  generally,  numerous  stamens 
with  yellow  anthers,  which  make  the  flower  conspicuous,  as  there 
are  no  petals  and  only  small  sepals.  The  Convolvulus  and  the 
Marsh  Pea  are  climbing  plants  that  make  use  of  the  Sedges  and 
Grasses  as  support,  matting  the  whole  together  into  a  luxuriant 
mass  of  vegetation.  The  Convolvulus  climbs  by  means  of  its 
twining  stem,  the  Marsh  Pea  by  tendrils.  The  Larger  Convolvulus, 
the  species  belonging  to  the  Fen  ditches,  differs  from  the  Bind- 
weed in  having  no  scent.  The  flower  remains  open  on  moonlight 
nights,  and  is  pollinated  by  the  Convolvulus  hawkmoth  ;  it  seldom 
sets  its  seeds  where  that  does  not  occur.  The  shade  formed  by 
these  plants  is  so  dense  that  certain  Ferns  and  Liverworts  are 
usually  found  sheltering  under  them. 

THE  VEGETATION  OF  RUNNING  WATER. — In  the  ditches 
intersecting  the  rough  meadows  of  the  Fen  country,  where  water 
runs  but  slowly,  three  plants  are  usually  found,  the  Greater  Spear- 
wort,  the  Small  Bur- Reed,  and  the  Sedge  (Car ex  Pseudo-cyperus) . 
All  these  plants  have  more  or  less  grass-like  leaves,  and  it  will  be 
found  that  plants  adapted  for  life  in  running  water  usually  have 
upright  aerial  leaves,  which  enable  them  to  stand  the  flow  of 
the  water  and  the  rush,  often  considerable  in  time  of  floods. 
This  type  of  leaf  is  more  usual  in  monocotyledons  than  in  dicoty- 
ledons, the  parallel  veins  of  monocotyledonous  leaves  suit  the 


VEGETATION  OF  RUNNING  WATER 


39 


vertical  habit  better  than  the  net-veined  leaf  of  the  dicotyledon  ; 
a  large  number  of  the  plants  growing  in  or  by  running  water  are 
monocotyledonous.  Where  the  running  water  is  very  shallow, 
and  the  plants  are  to  some  extent  submerged  in  it,  the  leaves  are 
not  vertical ;  the  plant  is  on  the  whole  creeping.  In  most  rivulets 
and  brooks  the  Brook  -  Lime,  the  Apium,  and  the  Water  -  Cress 
are  to  be  found.  The 
Brook-Lime  is  one  of  the 
Veronicas,  and  has  the 
characteristic  bright  blue 
flowers  of  that  genus ;  in 
this  species  they  are  not 
as  large  as  in  the  Ger- 
mander Speedwell,  a  com- 
mon weed  that  flowers 
early  in  spring  on  road- 
sides and  hedgebanks.  It 
is  a  smooth  shining  plant 
with  succulent  stems  and 
oval  glossy  leaves.  Like 
the  Brook  -  Lime,  the 
Apium  or  Marshwort  has 
a  creeping  stem  and  erect 
flowering  branches.  The 
whole  plant  is  smooth 
as  water  plants  generally 
are.  Each  leaf  consists  of 
from  three  to  ten  pairs  of 
leaflets;  the  flowers  are 
white.  This  is  a  very 

.    ,  ,        ,  .  .    .  FIG.  14. — Marshwort  (Apium  nodiftorum}. 

variable  plant ;  in  certain 

situations  it  may  be  several  feet  in  length,  but  it  is  usually 
very  much  shorter.  The  Water-Cress  (Nasturtium  officinale)  is 
a  cruciferous  plant,  now  very  much  cultivated,  especially  in  the 
southern  counties.  Great  care  is  now  taken  that  the  water  in 
which  it  is  grown  should  not  be  contaminated  by  sewage.  It 
is  important  that  the  beds  should  be  near  the  source  of  the 
water  supply,  in  order  that  the  temperature  may  vary  as  little 


40  THE  BOOK  OF  NATURE  STUDY 

as  possible  ;  a  gravelly  loam  is  the  best  soil ;  loose  sandy  loam, 
pure  clay  and  peaty  soils  are  to  be  avoided.  The  Cress  is 
propagated  by  division  of  the  plants :  this  is  done  between 
hay -making  and  harvest,  and  is  continued  until  the  end  of 
October.  The  top  of  the  plant  is  cut  out,  the  length  of  the 
cutting  averaging  one  foot,  but  this  varies  according  to  the  depth 
of  the  water.  Some  growers  cultivate  stocks  for  planting  in 
smaller  streams  isolated  from  the  main  bed,  in  order  to  get 
more  robust  plants.  The  beds  should  be  thoroughly  cleaned 
out  and  replanted  each  season.  The  growing  of  Water-Cress  is 
not  a  very  remunerative  industry,  but  it  does  give  employment 
during  the  great  part  of  the  year  to  those  engaged  in  it. 

The  presence  of  a  stream  has  great  influence  on  the  vegetation 
of  the  adjoining  hedge.  A  country  lane  with  a  stream  along  the 
lower  hedges,  woods  bordering  its  upper  end  and  pastures  beyond, 
will  afford  at  least  three  types  of  vegetation.  The  hedges  by 
running  water  will  luxuriate  in  such  plants  as  the  Rosebay  Willow- 
Herb,  the  Hemp  Agrimony,  the  Purple  Loosestrife,  and  the 
Meadow-sweet ;  while  underneath,  in  the  shade  afforded  by  them 
and  at  the  edge  of  the  water,  will  be  found  the  Golden  Saxifrage 
and  a  species  of  Bitter  Cress  (Cardamine  flexuosa).  The  Willow- 
Herbs  are  a  large  genus,  and  have  been  thus  named  from  the  re- 
semblance of  their  leaves  to  those  of  the  Willow,  which  is  often 
associated  with  it  on  the  banks  of  streams.  The  Rosebay  is  one 
of  the  largest  species,  reaching  even  four  feet  in  height ;  unlike 
many  of  the  other  species,  it  is  not  hairy.  The  flowers  are  purplish- 
red  and  very  showy,  and  the  stigma  is  deeply  four-lobed.  In 
identifying  the  different  species  of  Willow- Herbs,  one  of  the  first 
things  to  examine  is  the  stigma  ;  some  have  a  four-lobed  stigma, 
others  a  club-shaped  one.  This  plant  is  very  much  visited  by 
insects,  and  as  the  stamens  mature  before  the  ovules,  cross- 
pollination  usually  takes  place. 

The  Purple  Loosestrife  (Lythrum  Salicaria)  has  long  spikes 
of  rose-coloured  flowers,  which  are  very  interesting,  for  there  are 
three  types  of  these  flowers.  Each  has  two  sets  of  stamens, 
the  position  of  which  varies  with  regard  to  the  stigma.  The 
style  is  also  of  different  length.  In  one  type  it  is  short,  and 
the  two  rows  of  stamens,  six  in  each  row,  are  then  above  the 


VEGETATION  OF  RUNNING  WATER 


stigma  ;  in  the  second  type  the  style  is  of  medium  length,  and  the 
stigma  has  one  row  of  stamens  below  it  and  one  above  it.  In  the 
third  type  of  flower  the  style  is  long,  and  both  rows  of  stamens 
are  below  the  stigma.  This  plant  is  therefore  ^ 

said  to  have  trimorphic  flowers,  and  in  this 
particular  may  be  compared  with  the  Prim- 
rose, which  has  dimorphic  flowers.  The 
Purple  Loosestrife  must  not  be  confused 
with  the  Yellow  Loosestrife,  which  is  a 
Lysimachia  and  has  the  Primrose  type  of 
flower. 

The  Hemp  Agrimony  is  one  of  the  simp- 
lest of  the  Compositae ;  each  apparent  flower 
is  a  small  flower-head  consisting  of  four  or 
five  pale  reddish-purple  florets  contained  by 
an  involucre  of  about  ten  bracts.  Each  of 
the  little  flowers  is  in  structure  similar  to  a 
single  disc  floret  (the  yellow  florets)  of  the 
Daisy,  except  that  the  two  styles  are  in  this 
plant  much  longer.  The  florets  contain 
honey,  which  collects  in  the  long  narrow  tube 
of  the  corolla,  where  it  can  be  obtained  by 
butterflies.  The  Meadow-sweet  is  a  rosaceous 
plant  with  creamy  flowers  massed  together. 
The  fruits  are  not  so  well  known ;  they  are 
very  minute,  five  or  six  together,  as  each 
flower  consists  of  five  or  six  carpels  which 
are  not  joined  to  each  other  and  therefore 
form  the  same  number  of  fruits ;  each  con- 
tains one  seed  and  opens  to  let  it  out  in  the 
autumn,  and  is  therefore  a  follicle,  not  an 
achene,  as  the  fruits  of  many  of  the  Rosacese 
are.  The  Golden  Saxifrage  (Chrysosplenium) 
likes  a  wet  habitat,  and  is  found  not  only  in 
ditches  by  the  side  of  streams,  but  on  rocks 
kept  wet  with  the  spray  of  waterfalls  or 
trickling  rivulets.  It  differs  from  the  true  FIG  I5  _Purple  Loose. 
Saxifrage  in  having  no  petals.  The  stamens,  strife  (lyth. 


42  THE  BOOK  OF  NATURE  STUDY 

usually  eight  in  number,  are  inserted  on  the  four-lobed  calyx. 
The  flowers  are  small,  apparently  almost  seated  on  the  leaves. 
There  are  two  species,  distinguished  from  each  other  by  the 
arrangement  of  the  leaves  on  the  stem  ;  the  one  with  opposite 
leaves  is  far  more  abundant  than  the  alternate-leaved.  The 
Cardamines  all  like  damp  situations.  The  best-known  species 
is  the  Cuckoo-flower,  which  flowers  in  early  spring.  The  Cardamine 
flexuosa  is  the  one  found  at  the  edges  of  streams ;  it  may  be  re- 
cognised by  the  wavy  stem.  The  different  cresses  are  puzzling ; 
but  the  Nasturtiums,  or  Water  Cresses,  and  the  Cardamines  are 
almost  the  only  two  genera  of  the  Cruciferae  which  have  pinnate 
leaves.  The  genus  Nasturtium  is  quite  distinct  from  the  garden 
Nasturtium,  a  genus  of  the  Geraniaceae.  Another  plant  very 
characteristic  of  slow  running  water  is  the  Fleabane  (Inula  dy- 
senterica).  It  is  found  in  ditches  on  the  roadside  and  in  wet 
pastures.  All  the  florets  are  yellow,  the  outer  ones  very  spreading 
and  very  bright.  The  leaves  are  rough  above  and  downy  under- 
neath. This  is  one  of  those  plants  growing  in  damp  situations  with 
cottony  instead  of  smooth  leaves.  More  observation  is  necessary 
before  it  is  possible  to  give  any  explanation  of  this  fact.  A  com- 
parison of  the  different  species  of  Inula  shows  a  variety  of  habitat 
and  a  corresponding  diversity  in  regard  to  this  character  of  hairi- 
ness. Inula  Helenium  belongs  to  rich  hilly  pastures,  and  has 
leaves  which  are  nearly  smooth  above  and  downy  underneath. 
Inula  Conyza  (Ploughman's  Spikenard)  is  a  still  more  downy 
plant,  belonging  to  dry  situations.  Inula  crithmoides  (Golden 
Samphire)  is  a  seaside  plant  with  smooth  succulent  leaves,  whilst 
Inula  Pulicaria  (Small  Fleabane)  resembles  Inula  dysenteric*  in 
having  leaves  with  a  smooth  upper  surface  and  a  downy  under 
surface.  It  would  be  interesting  to  compare  as  many  different 
plants  as  possible  of  these  two  species,  with  a  view  to  discovering 
whether  the. under  surface  of  the  leaf  is  more  or  less  downy  the 
farther  the  plant  is  growing  away  from  water. 

THE  VEGETATION  OF  SWIFTLY  FLOWING  WATER. — RIVERS.— 
The  plants  growing  on  the  banks  of  a  river  lead  a  semi-aquatic 
existence  :  their  roots  and  stems  are  in  the  water  ;  their  leaves 
are  partly  in  and  partly  out  of  the  water  ;   they  flower  out  of  the 


VEGETATION  OF  SWIFTLY  FLOWING  WATER      43 


water.  Such  plants  have  to  accommodate  themselves  to  a  rush 
of  water,  and  to  changes  in  the  level  of  the  water  which  may 
be  considerable  during  flood.  The  organ  by  which  the  plant  is 
able  to  meet  these  conditions  is  the  leaf.  Plants  floating  in  more 
or  less  still  water  have,  as  already  noticed,  more  or  less  round 
leaves  with  air 
spaces.  This  type  of 
leaf  would  be  use- 
less here ;  it  would 
be  swamped  during 
floods.  The  long, 
narrow,  upright 
leaf  is  the  kind 
required.  Leaves 
of  this  type  bend 
with  the  water, 
and,  being  a  foot 
or  more  above  the 
surface,  are  un- 
affected by  the 
changes  of  level  in 
the  water.  The 
Sweet  Flag,  Bur- 
Reed,  Bulrush, 
Reeds  all  have 
long,  narrow,  up- 
right leaves,  and 
are  all  monocoty- 
ledons with  the 
veins  of  the  leaf 
parallel.  The  Sweet 
Flag  must  not  be 

r         i        .,1      ,i  FIG.  1 6. — Branched  Bur-Reed  (Sparganium  ramosum). 

confused  with  the 

Yellow  Flag  or  Yellow  Iris.  It  belongs  to  the  same  order 
as  the  Common  Arum,  which  grows  under  shady  hedges.  The 
Sweet  Flag  has  narrower  and  brighter  green  leaves  than  those 
of  the  Yellow  Flag,  with  an  aromatic  odour  when  bruised, 
and  their  margin  is  slightly  crimped.  The  flower-stems  are 


44  THE  BOOK  OF  NATURE  STUDY 

flattened,  and  the  dense  spike  of  sessile  flowers,  which  is  the 
termination  of  the  stem,  looks  like  a  projection  by  the  side  of 
the  leaf-like  bract,  which  in  this  genus  does  not  enclose  the 
inflorescence  as  the  bract  (spathe)  of  the  Arum  does.  The  spike 
contains  many  hundred  flowers,  which  do  not  produce  ripe  fruit, 
probably  because  there  are  not  the  right  insects  to  pollinate  it  in 
this  country,  as  it  does  produce  fruit  in  Asia,  its  native  continent. 
The  Bur-Reeds  and  the  Bulrushes  belong  to  the  Typhaceae. 
There  are  three  well-marked  species  of  Bur-Reed  (genus  Spar- 
ganium)  in  the  British  Isles.  The  largest,  Sparganium  ramosum, 
is  easily  recognised  by  the  flower  stem  branched  near  the  top  ; 
the  branches  are  given  off  alternately  on  each  side,  each  bearing 
six  or  more  heads  of  flowers  protected  by  a  leafy  bract.  The 
upper  heads  contain  staminate,  the  lower,  pistillate  flowers. 
The  Simple  Bur-Reed  (S.  simplex)  has  an  unbranched  flower 
stem  ;  the  flower-heads  are  fewer  and  at  considerable  distances 
from  each  other ;  the  lower  stalked  ones  produce  fruit,  the  upper 
ones  are  barren.  The  Small  Bur-Reed  (S.  minimum)  is  a  very 
much  smaller  plant,  with  narrow  leaves  that  float  on  the  surface. 
It  is  not  as  common  as  the  other  two  species,  and  belongs  to  still 
water  rather  than  to  rivers. 

The  Bulrushes  are,  strictly  speaking,  Reed-Maces  (genus 
Typha).  The  Great  Reed-Mace  (T.  lati folia)  has  a  short  root- 
stock  which  creeps  in  the  mud  and  from  which  erect  stems,  three 
to  six  feet  in  height,  ascend.  The  leaves  may  be  as  much  as  ten 
feet  in  length,  though  five  or  six  is  their  usual  height.  The  spike 
of  flowers  is  often  more  than  a  foot  in  length,  the  staminate 
flowers  being  above  the  pistillate.  In  the  smaller  species  of  Reed- 
Mace  (T.  angmtifolia)  there  is  a  distinct  interval  between  the 
two  sets  of  flowers.  When  the  flower-spikes  first  appear  among 
the  sheathing  leaves  they  are  wrapped  in  long  bracts  almost 
lace-like  in  their  delicacy ;  as  the  flowers  develop,  these  bracts 
float  off  in  the  air.  It  is  well  worth  watching  them.  The  fruits 
are  brown,  and  persist  during  the  winter.  When  they  become 
detached  from  the  spike,  the  hairs  borne  by  the  stalk  of  each 
fruit  act  as  wings  to  disperse  the  seed  ;  the  hairs  fluff  out  into 
downy  masses,  so  that  the  whole  spike  looks  about  a  hundred 
times  as  large,  for  a  single  head  will  contain  about  a  quarter  of  a 


VEGETATION  OF  SWIFTLY  FLOWING  WATER      45 

million  of  these  flying  seeds,  according  to  Professor  Lloyd  Praeger's 
estimate.  Another  plant,  sometimes  called  Bulrush,  is  the  Sedge, 
Scirpus  lacustris.  This,  unlike  most  of  the  Sedges,  is  a  leafless 
plant.  It  has  tall,  smooth  stems,  sometimes  six  or  eight  feet  in 
height.  The  length  of  the  stem  varies  with  the  habitat  of  the  plant. 
When  growing  by  the  edges  of  lakes  it  is  short,  sometimes  not 
more  than  six  inches  high ;  in  the  water  it  grows  very  much  taller. 

The  Arrowhead  (genus  Sagittaria)  and  the  Greater  Water 
Plantain  (Alisma  Plant  ago)  are  often  found  growing  in  rivers, 
not  as  near  the  banks  as  the  upright  plants.  Both  these  plants 
belong  to  the  Alismaceae,  and  have  rather  a  different  type  of 
leaves  from  the  upright  type.  They  are  not  long  and  narrow, 
but  more  lobelike  and  ovate  in  shape,  approximating  towards  the 
floating  type.  The  Arrowhead  is  easily  recognised  by  the  shape 
of  the  leaves,  which  develop  in  the  following  order.  The  first 
leaves  are  submerged  ;  then  come  linear  leaves,  the  upper  part  of 
which  floats  on  the  water.  Next  floating  leaves,  in  which  an 
ovate  blade  is  developed,  and  lastly  the  triangular,  deeply  sagittate 
leaves  from  which  the  plant  is  named.  The  leaves  of  the  Water 
Plantain  have  a  somewhat  similar  development.  The  flowers 
of  the  Arrowhead  have  three  small,  green  sepals  and  three  large 
white  petals,  with  a  deep  purple  spot  at  the  base  of  each.  The 
lower  flowers  are  pistillate,  and  are  on  shorter  stalks  than  the 
upper  staminate  ones.  The  flowers  of  the  Water  Plantain  in 
general  appearance  are  not  unlike  those  of  the  Arrowhead,  with 
this  distinction,  that  each  flower  contains  both  stamens  and 
carpels.  The  Flowering  Rush  may  also  be  mentioned  here,  as  it 
is  a  semi-aquatic  plant  belonging  to  the  Alismaceae,  but  it  frequents 
still  rather  than  running  wtaer.  It  is  not  a  Rush  at  all,  but  was 
probably  thus  named  from  the  rush-like,  leafless  flower-stem.  It 
has  rose-coloured  flowers.  With  these  plants  there  will  be  certain 
Grasses,  such  as  the  Common  Reed — as  it  is  called — (Phragmites 
communis)  and  the  Reed  Poa  (Glyceria  aquatica),  and  other  well- 
known  plants,  such  as  Docks,  Spearworts,  Yellow  Loosestrife,  etc. 

The  vegetation  of  the  banks  of  a  river  is  therefore  very  varied, 
so  varied  that  it  is  difficult  to  fix  on  one  dominant  plant.  The 
Bur- Reed  and  the  Reed  Mace  are  generally  about  equal  in  num- 
bers, whilst  Phragmites  communis  often  disputes  the  predominance 


46  THE  BOOK  OF  NATURE  STUDY 

with  them.  Under  these  circumstances  the  name  of  the  Plant 
association  is  based  on  the  type  of  leaf,  and  it  is  found  best  to 
speak  of  the  Upright-leaf,  the  Floating-leaf,  and  the  Submerged- 
leaf  associations,  and  under  these  headings  the  different  plants  are 
arranged  as  dominant  and  subdominant  species. 

The  marshy  ground  within  the  banks  of  the  river  has  also  its 
characteristic  vegetation.  The  plants  in  this  belt,  though  hardly 
aquatic,  are  distinctly  hydrophytic  ;  that  is  to  say,  they  live  in 
soil  which  has  a  very  high  percentage  of  water,  without  being 
constantly  bathed  by  water  as  the  banks  of  a  river  are.  The 
Butter-Bur,  the  Wild  Angelica,  the  Yellow  Meadow  Rue,  Water- 
cresses,  the  Water  Starwort,  certain  Willow  herbs  and  certain 
species  of  Orchis  are  among  the  most  common  in  this  situation. 

An  account  of  the  vegetation  by  river  sides  is  hardly  complete 
without  some  mention,  however  slight,  of  the  trees  that  most 
frequently  border  their  banks.  Pollard  Willows  (Salix  alba  and 
5.  fragilis  generally)  are  very  common  ;  the  trees  are  kept  cut 
down  to  a  particular  height  to  thicken  the  growth  at  the  top, 
from  the  stool-shoots  thus  produced  osier-rods  are  obtained, 
although  in  some  parts  of  the  country  another  species  of  Willow, 
Salix  viminalis,  is  specially  cultivated  for  this  purpose.  The 
ground  vegetation  of  an  osier  plantation  is  a  combination  of 
marsh  and  meadow  plants. 

Another  tree,  belonging  to  the  same  order  as  the  Willow,  and 
commonly  planted  near  streams,  is  the  White  Poplar,  which 
reaches  a  height  of  sixty  or  even  a  hundred  feet.  Its  branches 
spread  horizontally,  and  the  leaves  are  on  long,  slender  stalks. 
The  catkins  appear  in  March  and  April ;  the  staminate  ones  are 
about  four  inches  in  length,  each  flower  consisting  of  six  stamens 
with  purple  anthers.  The  pistillate  catkins  are  much  shorter,  and 
the  bracts  are  less  hairy  than  in  the  staminate  flowers. 

The  Alder  is  even  more  generally  associated  in  one's  mind 
with  streams  than  the  Poplar.  It  likes  not  only  the  moist  loam 
which  is  usually  to  be  had  near  a  river,  but  it  enjoys  the  damp 
mist  which  rises  from  it.  The  flowers  of  the  Alder  and  Willow 
have  already  been  described  (Vol.  IV.) 

Rivers,  it  must  be  remembered,  affect  vegetation  not  only 
through  the  influence  they  exert  on  the  degree  of  moisture  supplied 


AMPHIBIOUS  PLANTS 


47 


to  the  plants  on  their  banks,  but  also  by  the  debris  and  humus 
they  deposit  in  their  course.  A  river  that  is  flowing  at  the  rate 
of  only  three  inches  per  second  will  bring  down  fine  mud  ;  a 
velocity  of  six  inches  per  second  supplies  enough  force  to  carry 
down  fine  sand  ;  twelve  inches  will  move  fine  gravel  along  ;  twenty- 
four  inches  will  roll  along  rounded  pebbles  an  inch  in  diameter, 
whilst  a  velocity  of  three  feet  is  required  to  move  stones  about 
the  size  of  a  hen's  egg.  Rivers  flowing  through  calcareous  dis- 
tricts carry  down  a  great  deal  of  matter  dissolved  in  the  water  ; 
it  is  estimated  that  the  Thames  carries  down  no  less  than  450,000 
tons  of  salts  in  solution  annually. 


AMPHIBIOUS  PLANTS 

Some  few  plants  are  able  to  live  equally  well  in  water 
as  on  land ;  they  are  sufficiently  plastic  to  adapt  themselves 
to  either  medium.  The  best  known 
instance  of  this  is  the  Polygonum 
amphibium,  which  flourishes  equally 
well  on  the  top  of  a  bank  or  in  ten 
feet  of  water ;  but  the  character  of  the 
plant  varies  with  the  habitat.  When 
growing  in  dried-up  ponds,  or  muddy 
ditches,  the  stems  are  creeping  at  the 
base,  then  shortly  erect,  and  the  leaves 
are  often  downy.  On  the  top  of  a 
bank  the  plant  sends  up  erect  leafy 
stems,  usually  without  flowers.  In 
water,  the  long  stems  reach  the  sur- 
face ;  the  thick,  leathery  leaves,  three 
to  six  inches  long,  float  on  the  surface 
of  the  water,  and  dense  spikes  of  rose- 
coloured  flowers  project  out  of  the 
water.  The  Polygonums  are  closely 
allied  to  the  Docks,  but  are  less  stiff 
plants,  and  some  species  are  creeping 

or  floating.     The  Water-Pepper  Poly- 
Pic.  17.— Amphibious  Polygonum 

gonum  is  a  slender  plant,  sometimes         (Polygonum 


48 


THE  BOOK  OF  NATURE  STUDY 


creeping,  with  flowers  in  slender  spikes,  and  the  perianth  of  the 
flowers  dotted  with  small  glands.  It  is  found  in  wet  ditches  and 
on  the  edges  of  ponds  and  streams. 

It  seems  probable  that  aquatic  plants  have  originated  from 
land  plants,  which,  crowded  out  by  competition  with  each  other, 
may  have  lived  an  amphibious  life  for  a  time,  and  eventually 
taken  refuge  in  the  water  altogether.  Now  they  are  so  perfectly 
adapted  to  life  in  the  water  that  they  would  find  it  difficult  to 
live  on  land ;  it  is  easier  for  land  plants  to  adapt  themselves 

to  an  aquatic  existence 
than  for  water  plants  to 
return  to  a  mode  of  life 
determined  by  atmos- 
pheric conditions.  The 
influence  of  change  in 
external  conditions  on 
land  plants  has  been  in- 
vestigated in  the  Cuckoo 
flower  (Cardamine  pra- 
tensis),  plants  of  which 
were  found  submerged 
on  the  banks  of  a  pond 
that  had  overflowed. 
These  submerged  forms 
differed  from  the  terres- 
trial forms  in  the  follow- 
ing respects :  the  cauline 
leaves,  which  are  usually 
sessile,  had  developed 
long  stalks  ;  their  segments  were  narrower  ;  the  epidermis 
thinner.  The  nbro-vascular  bundles  of  the  stem  were  nearer 
the  centre,  and  the  cortex  was  much  thicker.  Some  of  these 
changes  would  take  place  if  the  plant  were  grown  in  a  medium 
of  moist  air  instead  of  water;  the  two  changes  which  appear 
to  be  specially  associated  with  the  liquid  condition  of  the  water 
are  the  displacement  of  the  vascular  bundles  and  the  narrow- 
ing of  the  leaf  segments.  Similar  results  have  been  observed  in 
one  of  the  Water  Crowfoots,  Ranunculus  fluitans,  and  in  other 


FlG.  1 8.— Water  Crowfoot  (Ranunculus  aquatilis). 


REPRODUCTION  OF  AQUATIC  PLANTS 


49 


plants  ;  it  is  therefore  considered  that  these  two  modifications 
are  the  first  stage  towards  the  transformation  of  a  terrestrial 
plant  into  an  aquatic  plant.  It  is  clear  from  the  observations  on 
the  Cardamine  pratensis  that  these  changes  were  brought  about 
by  the  influence  of  external  conditions ;  but  this  plant  does  not 
appear  able  to  hold  its  own  as  an  aquatic  plant, — probably  the 
changes  thus  brought  about  by  the  pressure  of  environment  are 
not  handed  down,  in  the  case  of  this  plant  at  any  rate,  by  natural 
selection. 


THE  REPRODUCTION  AND  DISPERSION  OF  AQUATIC  PLANTS 

Life  in  the  medium  of  water  is  favourable  to  vegetative  re- 
production. The  rapid  spread  of  the  Elodea  canadensis  has 
already  been  noticed  (p.  22),  the  growth  of  the  Frog-Bit,  a  closely 
allied  genus,  may  be  given  here. 
This  plant  sends  out  long  runners, 
which  give  off  at  intervals  tufts  of 
floating  leaves  above,  and  roots 
hanging  down  in  the  water.  This 
method  of  multiplication  is  similar 
to  that  of  the  Strawberry.  In  the 
autumn,  buds  form  at  the  end  of 
the  shoots,  sink  to  the  bottom  while 
the  rest  of  the  plant  decays,  and  the 
following  spring  they  rise  to  the 
surface  and  grow  into  new  plants. 
The  distribution  of  this  plant  is  not 
as  wide  as  that  of  the  Elodea,  but 
it  does  belong  to  both  Europe  and 
Asia  and  is  common  in  many  parts 
of  England  and  Ireland. 

The  Algae  are  usually  fertilised 
in  water,  but  Flowering  Plants  are 
not  as  a  rule.  The  Brown  and  Red 
Sea-weeds,  the  Green  Algae  of  ponds  are  all  reproduced,  not 
only  by  vegetative  processes,  but  by  fertilisation.  In  the 
case  of  Flowering  Plants,  however,  seed  is  not  usually  formed 

VOL.  V. — 4 


FIG.  19. — Frogbit  (Hydrocharis 
M or sus- Ranee). 


50  THE  BOOK  OF  NATURE  STUDY 

in  water.  The  majority  of  aquatic  plants  protrude  their  flower- 
ing stems  above  the  water  in  order  to  produce  flowers  and 
make  seed  ;  the  Water  Plantain,  the  Arrowhead,  and  many 
others  will  not  flower  if  completely  submerged,  whilst  the  Awl- 
wort  when  completely  submerged  forms  cleistogamous  flowers, 
i.e.  flowers  which  never  open  and  are  self  -  pollinated.  There 
are  only  about  fifty  Flowering  Plants  adapted  for  pollination 
and  fertilisation  in  water.  The  Grass- Wrack  (Zoster a),  a  marine 
plant  abundant  in  the  brackish  water  of  lagoons  and  off  muddy 
seashores,  has  peculiarly  formed  pollen.  The  outer  coat  character- 
istic of  the  pollen  grains  of  land  plants  is  absent ;  the  anthers 
open  under  water,  and  as  soon  as  the  pollen  cells  are  liberated 
they  take  the  form  of  long  cylindrical  tubes,  which  are  carried 
by  the  water  to  the  stigmas  of  the  pistillate  flower.  The  Naiad 
have  pollen  of  the  same  character.  Those  aquatic  plants  which 
discharge  their  pollen  above  the  surface  of  the  water  have  pollen 
grains  with  the  usual  outer  coat,  and  they  are  round  or  elliptical, 
not  cylindrical  or  tube-like. 

For  the  dispersion  of  their  fruits  and  seeds,  aquatic  plants  are 
frequently  provided  with  means  of  floating.  Schimper  mentions 
a  definite  floating  bladder  in  the  case  of  the  Morinda  citri folia, 
but  the  majority  of  these  aquatic  plants  merely  have  fruits  with 
tissues  containing  plenty  of  air  spaces,  which  make  them  light 
and  buoyant  and  able  to  float  great  distances.  The  double  coco- 
nut of  the  Seychelles  Islands  has  been  found  on  the  coast  of  Su- 
matra 3000  miles  distant ;  the  fruits  of  the  Soap-Berry  (Sapindus 
Saponaria)  have  been  brought  to  Bermuda  by  the  Gulf  Stream 
from  the  West  Indies,  and  the  West  Indian  bean,  Entada  scandens, 
has  travelled  as  far  as  the  Azores,  about  3000  miles.  Facts  of  this 
kind  are  of  peculiar  interest,  as  they  explain  the  resemblance  of 
the  shore  flora  of  such  widely  separated  land  as  the  Malay 
Archipelago  and  the  Central  Pacific  islands. 

The  coco-nut  bought  in  England  gives  no  idea  of  the  tissue 
by  which  the  fruit  floats.  The  fibrous  covering  has  been  stripped 
off  to  be  made  into  ropes  and  other  articles  of  commerce,  and 
what  is  bought  is  usually  the  hard  shell  with  the  white  endosperm 
inside.  It  is  this  husk  of  fibrous  tissue  with  plenty  of  air  spaces 
in  it  which  enables  the  nut  to  float  these  immense  distances  ; 


DISPERSION  OF  AQUATIC  PLANTS  51 

the  sea-water  cannot  enter  the  coco-nut,  because  the  outside  of 
the  husk  is  coated  by  a  layer  with  fatty  contents,  which  prevents 
the  infiltration  of  water. 

The  number  of  fruits  or  seeds  capable  of  floating  on  the  water 
for  any  length  of  time  is  small ;  most  sink  at  once,  and  sooner  or 
later,  undergo  decomposition  at  the  bottom  of  the  sea.  It  has 
been  ascertained  by  experiment  that  the  seeds  of  several  plants 
can  be  immersed  in  sea-water  for  over  a  year  and  yet  not  lose 
their  power  of  germination. 

Fresh- water  plants,  such  as  the  Sedges,  Water  Plantains, 
Flowering  Rushes,  Bur- Reeds  are  dispersed  by  the  wind  blowing 
them  as  they  float  on  the  surface  of  the  water.  The  fruit  of  the 
Sedge  is  enclosed  in  a  bag,  called  the  utricle ;  this  acts  as  a  bladder, 
the  space  between  the  utricle  and  the  nut  being  filled  with  air ; 
by  this  means  the  fruit  is  able  to  keep  afloat,  and  is  blown  along 
from  bank  to  bank,  or  from  marsh  to  marsh.  The  seeds  of  the 
Arrowhead  are  not  wetted  by  water,  and  therefore  float ;  the 
fruits  of  Water  Plantains,  Bur- Reeds,  and  other  water  plants  are 
furnished  with  a  cortical  tissue  containing  a  great  deal  of  air 
that  makes  them  light. 

In  the  Yellow  Water-Lily  the  walls  of  the  carpels  separate 
into  two  layers  ;  the  outer  one  is  green  and  succulent,  the  inner 
is  white  and  charged  with  air,  which  keeps  the  fruit  afloat.  In 
the  white  Water-Lily  each  seed  has  a  coat  (arillus)  round  it,  the 
space  between  this  and  the  testa  is  filled  with  air,  enabling  the 
seed  to  rest  on  the  water  until  it  is  driven  along  by  the  wind. 

Fruits  or  seeds  which  have  structures  enabling  them  to  keep 
afloat  may  be  dispersed  not  only  by  the  wind  blowing  them  along 
the  water,  but  by  adhering  to  the  beak,  legs,  or  feathers  of  birds 
which  come  to  the  water's  edge  to  drink.  Even  seeds  that  do  not 
float,  but  sink  into  the  mud,  may  be  dispersed  in  this  way,  as  the 
mud  sticks  to  the  feet  of  the  birds.  Darwin's  experiments  on 
the  number  of  seeds  imbedded  in  mud  gave  some  very  striking 
results;  as  many  as  537  plants  were  obtained  from  the  seeds 
contained  in  6f  ounces  of  mud.  Now,  many  birds  fly  at  the  rate 
of  forty  miles  per  hour,  swallows  about  one  hundred  miles  an  hour ; 
seeds  adhering  to  them  may  therefore  be  dispersed  at  considerable 
distances  from  the  parent  plant.  Kerner  in  his  investigations 


52  THE  BOOK  OF  NATURE  STUDY 

found  seeds  of  the  Purple  Loosestrife,  the  Water  Cresses,  Rushes, 
Sea  Milkwort,  Sedges,  Grasses,  the  Brook-weed  (Samolus)  in  the 
mud  taken  from  birds.  Cattle  convey  the  seeds  of  marsh  plants 
through  the  mud  which  sticks  to  their  hoofs. 

A  large  number  of  water  plants,  perhaps  the  greater  pro- 
portion, have  their  seeds  dispersed  by  the  wind.  These  plants 
flower  and  seed  well  above  the  surface  of  the  water,  and  their  fruits 
or  seeds  are  provided  with  appendages  which  allow  them  to  be 
wafted  about  by  the  wind.  Others  are  provided  with  hooks, 
or  bristles,  which  adhere  to  the  rough  coats  of  sheep,  goats,  oxen, 
and  horses  that  come  down  to  the  river,  or  marsh,  and  are  thus 
dispersed. 

Although  most  fruits  and  seeds  are  provided  with  structures 
for  dispersion,  it  is  conceivable  that  they  may  not  be  carried  any 
distance  from  the  parent  plant ;  but  under  certain  circumstances, 
such  as  the  absence  of  wind  or  the  non- visits  of  animals,  may  fall 
in  the  immediate  neighbourhood  of  the  mother-plant.  Nature 
allows  for  great  loss  of  seeds  through  many  failing  to  germinate 
for  want  of  right  conditions.  When  a  plant  sheds  its  seeds  in  its 
own  spot  of  ground  the  seeds  on  germinating  must  choke  each 
other,  and  only  a  few  will  grow  into  adult  plants.  The  number 
of  seeds  produced  yearly  by  a  single  plant  is  enormous,  and  may 
reach  several  thousands,  but  in  order  to  keep  up  the  present 
number  of  plants,  only  a  very  few  of  these  need  grow  up  into 
adult  plants,  and  unless  there  were  great  loss  of  seeds  the  earth 
would  soon  be  too  small  to  contain  all  the  descendants  of  any  one 
plant.  The  loss  of  life,  however,  in  seeds,  in  seedlings,  and  in  adult 
plants  is  immense,  owing  to  changes  of  temperature,  to  floods,  to 
destruction  by  animals  and  by  man  ;  and  unless  there  were  con- 
trivances for  dispersion,  as  well  as  an  immense  quantity  of  seed 
produced,  many  plants  would  soon  die  out ;  as  it  is,  certain 
water  plants  belonging  to  the  Fen  district  are  much  rarer  than 
they  used  to  be,  owing  to  better  drainage. 

THE  COLOUR  OF  WATER  INFLUENCED  BY  VEGETATION 

Many  Algae  give  a  distinct  coloration  to  water,  snow,  and  ice. 
It  is  a  matter  of  common  experience  that  the  rain-water  in  a  cistern 


COLOUR  OF  WATER  AND  VEGETATION  53 

is  sometimes  green  or  red.  This  is  due  to  one  of  the  simplest  of  our 
Algae,  the  Protococcus,  an  organism  consisting  of  one  cell,  in  the 
protoplasm  of  which  red  and  green  colouring  matter  is  suspended. 

It  is  another  Alga,  very  similar  in  structure  to  Protococcus, 
that  makes  snow  red,  as  travellers  have  often  noted.  The  red 
colouring  may  extend  to  the  depth  of  two  inches,  and  appears  to 
occur  on  most  mountains  with  perpetual  snow.  This  phenomenon 
has  been  observed  both  in  the  Arctic  and  Antarctic  zones ;  on 
the  Alps,  Scandinavian  mountains,  and  on  the  Andes.  Ice  has 
sometimes  a  superficial  brown  layer,  due  to  those  organisms  which 
can  thrive  on  fine  dust. 

The  colour  of  the  water  in  lakes  has  been  the  subject  of  some 
experiment.  As  every  one  knows,  many  lakes  have  a  distinct 
colour  of  their  own,  independently  of  the  tints  due  to  changes  in 
the  sky.  Some  are  intensely  blue,  others  green  or  yellowish, 
some  almost  colourless.  The  natural  colour  of  pure  water  in 
sufficient  quantity  is  blue  ;  the  crevasses  in  glaciers  are  blue  ; 
why,  then,  should  the  water  of  some  lakes  be  green  ?  It  is  sug- 
gested that  blue  is  turned  into  green  by  minute  quantities  of 
organic  matter  in  solution.  The  blue  water  of  the  Lake  of  Geneva 
was  turned  into  a  green  colour,  similar  to  that  of  the  Lake  of 
Lucerne,  by  adding  to  it  an  infusion  of  peat.  Forel,  who  tried 
these  experiments,  instances  in  support  of  his  theory  the  two 
lakes  of  Achensee  and  Tegernsee  in  the  Tyrol.  The  former  is 
blue,  the  latter  green  ;  the  basin  of  the  former  is  free  from  peat, 
that  of  the  latter  is  covered  with  peat  mosses. 

This  does  not  account  for  the  greenish  tint  of  sea-water  near 
the  shore.  Shallow  water  over  yellowish  sand  would  look  green 
from  the  reflection  of  the  yellow  light  at  the  bottom  of  the  water. 
The  constantly  varying  tints  of  river,  lake,  and  sea  are,  however, 
due  above  all  to  the  sun,  and  to  the  changes  in  the  intensity  of  the 
rays  of  light. 

SUGGESTIONS  FOR  PRACTICAL  WORK  ON  AQUATIC  PLANTS 

I.  Note  the  Plant  associations — 

(a)  In  bogs.  There  are  at  least  three  well-marked  associ- 
ations (p.  35). 


54  THE  BOOK  OF  NATURE  STUDY 

(b)  By  the  banks  of  streams,  rivers,  and  lakes.     The  Upright- 
leaf  association. 

(c)  In    ponds,    lakes,    and    in    the    river.     The    Floating-leaf 
association. 

(d)  In  marshes.     Often  a  combination  of  pasture  and  aquatic 
plants  will  be  found. 

(e)  Submerged  plants,  found  in  ditches  and  shallow  pools. 
The  special  organ  to  observe  in  detail  is  the  leaf,  the  structure 

of  which  varies  considerably. 

II.  The  difference  in  the  leaves  of  the  same  plant  when  in 
water,  and  when  out  of  water.     The  Brooklime  and  the  Water 
Crowfoot  are  typical  plants  to  observe  in  this  connection. 

III.  The  absence  of  hairiness  in  water  plants.     There  are  a 
few  plants  growing  by  water  which  are  undoubtedly  hairy.     A 
list  should  be  made  of  these,  and  compared  with  the  same  species 
growing  inland,  in  order  to  ascertain  whether  the  plants  growing 
by  the  water  are  more  or  less  hairy  than  those  inland.     The 
Meadow-sweet  and  the  Forget-me-not  give  good  results. 

IV.  The  effect  of  growing  land  plants  submerged  in  water. 
This  may  be  observed  under  natural  conditions,  as  in  the  over- 
flowing of  a  pond  or  river  ;    or  under  artificial  conditions.     The 
seedlings  of  plants,  which  normally  grow  in  damp  places,  might 
be  grown  in  an  aquarium  or  large  tank,  and  the  results  noted. 
Similarly,  the  result  of  growing  water  plants  out  of  water  may 
be  tried,  and  the  one  set  of  results  compared  with  the  other. 

V.  The  influence  of  man,  seen  in — 

(a)  The  draining  of  marshy  districts,  with  the  result  that 
certain  species  are  becoming  extinct. 

(6)  The  altering  of  the  level  of  lakes  ;  or  the  creation  of 
lakes. 

(c)  The  pollution  of  rivers,  especially  in  country  districts,  where 
sewage  arrangements  are  sometimes  non-existent. 

(d)  The    abandoning    of    mills    and    of    brick-ponds.     Under 
these  circumstances,  nature  is  left  undisturbed,  and  there  will 
probably  be  a  succession  of  Plant  associations.      This  kind  of 
observation  is  practicable  for  class  work  in  those  localities  which 
have  mills,  or  brick  fields,  within  easy  reach  of  them. 

VI.  The  effect  of  running  water  on  Hedgerow  vegetation. 


PRACTICAL  WORK  55 

(a)  Note  the  dominant  shrub,  or  tree,  in  hedges  with  a  stream 
running  by  them.     Some  species  of  Willow  will  be  often  found. 

(b)  Note  the  tall,  upright  plants,  such  as  Rosebay  Willow-herb. 

(c)  Note  the  herbaceous  vegetation  at  the  bottom  of  the  hedge  ; 
examine  the  stems  and  leaves  of  these  plants  as  regards  their 
hairiness,  their  succulence,  the  thinness  of  their  epidermis,  and 
their  reduced  fibro- vascular  tissue  (bast  and  wood).      Compare 
these  plants  with  those  found  in  a  hedge  by  the  side  of  which 
there  is  no  water.     The  observation  of  hedges  is  also  work  that 
can  very  easily  be  done  by  classes  of  students. 

BIBLIOGRAPHY. — Kerner,  Natural  History  of  Plants,  vol.  ii. ;  Schimper,  Plant 
Geography ;  Step,  Wild  Flowers  Month  by  Month ;  Scott-Elliott,  Nature  Studies ; 
Lord  Avebury,  British  Flowering  Plants;  Marr  and  Shipley,  Natural  History 
of  Cambridgeshire;  Darwin,  Insectivorous  Plants. 


CHAPTER  III 

THE  VEGETATION  OF  MEADOWS  AND  PASTURES 

MEADOWS  and  pastures  have  much  in  common  as  far  as  their 
vegetation  is  concerned,  and  are  of  special  interest  from  the  fact 
that,  more  than  any  other  natural  area,  they  show  the  effect  of 
man's  influence.  For  this  reason  the  Plant  Associations  found 
in  them  are  artificial,  not  natural.  In  a  good  meadow,  or  pasture, 
the  ground  is  covered  with  a  compact  growth  of  Grasses,  forming 
so  thick  a  carpet  that  the  colour  of  the  soil  is  often  entirely  con- 
cealed. Such  a  grass  carpet  consists  of  the  densely  interwoven 
rootlets  and  rhizomes  forming  a  sod,  and  is  rich  in  humus  from 
the  accumulation  of  years.  In  temperate  climates,  such  as  our 
own,  the  meadow  is  characterised  by  its  fresh  green  tint,  which 
is  preserved  even  in  winter,  for  the  grasses  are  practically  ever- 
green in  their  habit,  young  green  leaves  being  ready  to  take  the 
place  of  the  yellow  old  ones  almost  immediately. 

GRASSES  DOMINANT. — Grasses  may  be  distinguished  from  all 
other  plants  by  having  their  leaves  arranged  in  two  rows  alternately 
up  the  stem ;  and  by  the  circular  outline  of  the  cut  stem.  The 
leaves  have  no  leaf-stalk,  but  a  blade  and  a  sheath,  which  is 
nearly  always  split.  In  many  Grasses  there  is  an  outgrowth 
from  the  blade  where  it  joins  the  sheath  ;  this  is  the  ligule,  which 
prevents  the  water  that  falls  on  the  leaf  running  down  the  sheath 
and  rotting  the  stem.  Grasses  have  fibrous  roots,  and  many  of 
them  long  creeping  underground  stems,  which  break  up  stiff  soils. 
The  end  of  May,  or  the  beginning  of  June,  is  the  best  time  for 
observing  their  inflorescence,  and  the  Oat  is  one  of  the  easiest  with 
which  to  begin,  on  account  of  the  large  spikelets.  Each  spikelet 
consists  of  scales,  known  popularly  as  "  chaff/1  and  of  three 
flowers.  Some  grasses  have  only  one  or  two  flowers  in  each 
spikelet.  When  dissected  out,  the  following  structures  are 
seen  (Fig.  20). 


VEGETATION  OF  MEADOWS  AND  PASTURES        57 

1.  Two  large  scales,  at  the  bottom  of  the  spikelet ;    these  are 
the  glumes,  situated  one  just  above  the  other.      The  tip  of  the 
glume  may  be  extended  into  a  stiff,  long,  bristle-like  structure, 
called  the  awn. 

2.  Three  flowers,  each  in  the  angle  of  a  pair  of  minute  scales, 
called  pales. 

3.  Each  flower  consists  of  three  stamens  and  an  ovary  with 
two  plume-like  stigmas. 

In  June,  when  the  Grasses  are  ripe,  the  anthers  may  be  seen 
almost  covering  the  spikelets,  and  swaying  with  each  breath  of 
wind  ;  for  the  flowers  are  wind-pollinated.  It  has  been  observed 
that  they  have  as  a  rule  definite  hours  for  opening :  some  begin 
as  early  as  four  or  five  in  the  morning  ;  the  majority  about  six 
or  seven ;  Seashore  and  Moor  Grasses 
between  twelve  and  one,  and  some  few 
species  not  until  afternoon. 

As  many  as  twenty  or  thirty  species  of 
Grasses  may  be  found  in  a  meadow.  Those 
most  commonly  sown  for  hay  are  :  the  Rye 
and  Oat,  the  Cock's-foot,  the  Foxtail,  the 
Sheep's  and  Meadow  Fescue,  the  Sweet  FIG.  20.— Flower  of  a  Grass : 
Vernal,  and  the  Meadow  Grass.  Of  the  ^  outer  glumes  ;£?-,  inner 

^  ,  T     , .        \     ,  i  glumes ;    s,   stamens ;    sf. 

Rye  Grasses  (genus  Lolmm),  the  one  most        stigmus. 

commonly    planted    in    meadows    is    the 

Italian  Rye  Grass.      The  genus  may  be  identified  by  the  red 

colour  of   the   sheath    and   the  arrangements  of  the  spikelets. 

They  are  opposite  each  other,  and  each  has  only  one,  not  two, 

glumes. 

The  Cock's-foot  (Dactylis  glomerata)  is  easy  to  recognise,  for 
the  spikelets  are  crowded  together,  and  the  inflorescence  in  shape 
is  not  unlike  a  cock's  foot.  The  leaves  are  bluish-green  in  colour. 
It  is  a  perennial,  and  forms  dense  tufts.  It  is  a  valuable  grass 
for  a  meadow,  because  after  it  is  mown  and  made  into  hay  it 
grows  again  rapidly,  and  gives  an  abundant  second  growth,  or 
aftermath.  The  Foxtail  (Alopecurus  pratensis)  has  a  brown,  or 
black,  sheath.  It  is  one  of  the  earliest  grasses  to  flower ;  the  spike 
has  much  the  appearance  of  a  round  tail  ending  in  a  point,  and 
is  soft  to  the  touch  ;  it  flowers  from  the  middle  of  April  to  June. 


58  THE  BOOK  OF  NATURE  STUDY 

It  is,  unlike  the  Cock's-foot,  one  of  the  best  Grasses  for  producing 
an  even  sward,  by  means  of  its  short  creeping  stems,  or  stolons. 
The  Sweet  Vernal  (Anthoxanthum  odoratum)  also  flowers  early.  It 
is  mainly  this  grass  which  gives  the  sweet  scent  to  newly  mown 
hay.  The  spikelets  cover  the  entire  surface,  and  each  has  but 
one  perfect  flower,  with  two,  instead  of  three  stamens. 

The  Meadow  Fescue  (Festuca  elatior)  is  a  large  grass,  often 
over  three  feet  high.  The  sheath  is  red,  and  there  is  no  ligule. 
It  may  be  distinguished  from  the  Brome  Grass,  which  in  some 
respects  it  closely  resembles,  by  the  split  sheath.  The  Meadow 
Grass  (Poa  pratensis)  is  a  perennial  with  long  stolons.  It  is  of 
great  value  for  "  bottom  grass,"  but  yields  only  thin  hay.  It 
has  four  to  five  flowers  in  each  spikelet. 

Grasses  are  not  the  only  plants  found  in  meadows.  Clovers 
and  a  certain  number  of  plants,  useless  as  far  as  food  is  concerned, 
and  therefore  called  "Weeds,"  form  a  certain  proportion,  though 
a  varying  one,  of  all  grassland.  The  Clovers  are  leguminous 
plants,  and  of  great  value  from  the  power  they  possess  of  enriching 
the  soil  with  nitrogen,  through  the  bacteria  present  in  the  tubercles 
of  their  roots.  These  bacteria  have  the  power  of  "fixing"  the 
free  nitrogen  of  the  air.  The  four  Clovers  most  common  in 
meadows  are — 

1.  The  White  Clover,  which  flowers  from  May  to  October, 
and  is  most  abundant  in  soil  containing  lime. 

2.  Broad  or  Red  Clover,  which  is  found  practically  everywhere. 

3.  Perennial  Clover  or  Cow  Grass,  also  very  common. 

4.  Alsike  Clover,  which  is  found  in  moist  soil. 

The  structure  of  the  Clover  flower  differs  from  that  of  the 
Bean  or  Pea  in  the  fact  that  the  petals  and  stamens  are  united 
to  each  other. 

EFFECT  OF  MANURES  ON  GRASSLAND.— At  the  Rothamsted  Ex- 
perimental Station,  experiments  on  the  effect  of  certain  manures  on 
grassland  were  begun  in  1856,  and  have  been  continued  without 
intermission.  These  have  been  tried  on  some  twenty  plots  of 
ground,  each  about  a  quarter  of  an  acre  in  extent.  The  land  chosen 
has  been  under  grass  for  some  centuries,  and  as  far  as  is  known  no 
fresh  seed  has  been  sown.  Since  1874  there  has  been  no  grazing 


VEGETATION  OF  MEADOWS  AND  PASTURES        59 

on  these  plots,  and  the  grass  has  been  cut  twice  in  the  year.  The 
hay  made  has  been  weighed,  and  exact  records  have  been  kept 
of  the  manure  given  to  each  plot  and  the  yield  from  each.  Two 
of  the  plots  have  been  left  without  manure  during  the  whole 
period  ;  other  plots  have  been  given  nitrogenous  manures  entirely, 
namely,  ammonium  salts  and  nitrate  of  soda.  Others  again  have 
been  dressed  with  mineral  manures  alone  ;  a  fourth  set  have 
had  nitrogenous  and  mineral  manure.  The  unmanured  plots 
do  not  show  any  great  diminution  in  the  weight  of  the  hay,  but 
the  character  of  the  grass  has  very  much  deteriorated  during  the 
fifty  years,  and  the  weeds  form  a  larger  percentage  than  they 
formerly  did ;  in  1902  they  reached  the  high  figure  of  50  per 
cent.  The  Quaking  Grass,  the  Sheep's  Fescue,  Bird's-foot  Trefoil, 
Black  Knapweed,  Burnet,  and  Hawkbit  are  among  the  most 
prominent  weeds  in  these  unmanured  plots. 

The  plots  dressed  with  nitrogenous  manures  have  given 
different  results  according  to  the  manure  used.  The  average 
yield  of  hay  was  35  cwt.  per  acre  when  nitrate  of  soda  alone  was 
used,  and  only  26  cwt.  in  the  case  of  ammonium  salts.  On  the 
plots  manured  with  nitrate,  deep-rooting  Grasses  such  as  the 
Meadow  Foxtail  and  the  Downy  Oat  Grass  were  conspicuous  ; 
on  the  plots  with  ammonium  salts,  the  Sheep's  Fescue  and  the 
Common  Bent,  which  have  a  shallower  root  system  were 
dominant,  for  the  nitrate  of  soda  sinks  down  into  the  soil, 
whilst  the  ammonium  salts  are  retained  by  the  surface  layers. 
Leguminous  plants  are  practically  absent  from  these  plots. 

The  plots  to  which  mineral  manures  alone  have  been  given 
have  not  suffered  from  the  want  of  nitrogen,  owing  to  the  fact 
that  leguminous  plants  can  use  the  free  nitrogen  of  the  air ;  the 
yield  of  hay  per  acre  was  38  cwt.  One  plot  to  which  mineral 
manure  without  potash  was  given  has  shown  some  striking  results. 
The  yield  per  acre  is  much  less,  owing,  it  is  thought,  to  the  reduced 
percentage  of  leguminous  plants  which  seem  to  require  potash. 
The  most  productive  manure  has  proved  to  be,  as  might  be 
expected,  a  combination  of  mineral  and  nitrogenous  substances, 
when  the  yield  per  acre  has,  in  some  cases,  reached  as  high  a 
figure  as  72  cwt. 

Another  especially  interesting  result  is  the  effect  of  a  change 


60  THE  BOOK  OF  NATURE  STUDY 

of  manures  on  the  composition  of  the  herbage.  The  effect  of 
changing  to  mineral  manure  from  ammonium  salts  was  to  increase 
the  percentage  of  leguminous  plants  to  35  per  cent.,  to  lessen 
the  weeds  by  20  per  cent,  and  the  grasses  by  about  15  per  cent. 
A  change  from  nitrogenous  to  mineral  manure  without  potash 
reduced  the  leguminous  plants  from  about  20  to  5  per  cent. 

One  practical  conclusion  that  has  been  drawn  from  these 
experiments  on  grassland  is,  "  that  it  is  better  to  lay  up  the  same 
land  for  hay  each  year,  grazing  the  aftermath  only,  and  in  the 
same  way  always  to  graze  other  land,  rather  than  graze  and  hay 
in  alternate  years."  This  is  an  important  conclusion,  which 
should  be  more  widely  known  than  it  apparently  is,  for  in  many 
parts  of  the  country  it  is  usual  to  use  the  same  meadow  for  mowing 
and  pasture  in  alternate  years.  The  Rothamsted  experiments 
also  show  that  "  land  which  is  growing  hay  requires  a  manure 
which  is  mainly  nitrogenous,  whilst  pasture  requires  a  mineral 
manuring."  (Rothamsted  Experiments,  by  A.  D.  Hall.) 

WEEDS  COMMON  IN  MEADOWS. — Some  of  the  more  common 
weeds  in  meadows  are  :  the  Common  Bent  Grass,  the  Yorkshire 
Fog,  the  Quaking  Grass,  Clovers,  the  Bird's-foot  Trefoil,  Burnet, 
the  Beaked  Parsley,  the  Ribwort  Plantain,  Yarrow,  Sorrel,  and 
many  others.  The  Common  Bent  Grass  (Agrostis  vulgaris]  is 
characteristic  of  poor  land  ;  it  has  thin  dry  leaves,  rough  on  both 
sides,  and  the  sheath  is  colourless.  The  Yorkshire  Fog  (Holcus 
lanatus)  is  a  perennial,  with  an  upright  woody  stem  ;  it  is  a  widely 
distributed  weed.  The  Black  Knapweed,  or  Hardheads,  is  easily 
recognised  by  the  bracts  of  the  involucre,  which  are  brown,  or 
black,  and  deeply  fringed.  The  outer  florets  are  purple,  and 
without  stamens  or  ovules.  The  Yarrow  is  also  a  Composite, 
with  about  five  or  six  ray  florets,  generally  white  or  pink,  and 
with  yellow  disc  florets.  The  plant  has  very  finely  divided  leaves. 
The  Sorrel  is  a  dock-like  plant ;  in  poor  pastures,  where  it  is  often 
abundant,  it  forms  a  sheet  of  red.  The  Beaked  Parsley  (Anthriscus 
sylvestris)  is  an  umbelliferous  plant  with  umbels  of  small  white 
flowers.  The  Salad  Burnet  (Poterium  Sanguisorba)  belongs  to  the 
Rosacese.  It  is  one  of  the  few  genera  without  petals.  Each 
head  contains  both  staminate  and  pistillate  flowers ;  the  former 


VEGETATION  OF  MEADOWS  AND  PASTURES        61 


have  stamens  with  long  filaments,  so  that  the  anthers  swing  in 
the  air,  and  the  plant  is  wind-pollinated.  The  pistillate  flowers 
have  tufted  stigmas,  reddish  purple  in  colour. 

Certain  of  these  weeds  are  characteristic  of  particular  manures. 
It  is  found  at  Rothamsted  that  the  Beaked  Parsley  is  a  prominent 
weed  when  nitrate  of  soda  has  been  used  ;  the  Buttercup,  the 


FIG.  21. — Black  Knapweed  (Centaurea 
nigra). 


FIG.  22.— Salad  Burnet  (Poterium 
Sanguisorba). 


Black  Knapweed,  Plantain,  and  Yarrow  were  characteristic  of 
the  plot  which  had  been  deprived  of  potash,  and  the  Bird's-foot 
Trefoil  was  the  most  marked  of  the  leguminous  plants  in  the 
same  plot,  because  Clover  and  other  taller  leguminous  plants 
which  usually  keep  out  the  Bird's-foot  Trefoil  had  not  grown 
owing  to  the  want  of  potash.  Sorrel  is  found  to  be  characteristic 
of  those  meadows  where  nitrogenous  manures,  such  as  ammonium 


THE  BOOK  OF  NATURE  STUDY 


salts,  have  been  used  without 
mineral  manure  ;  it  is  a  weed 
indicative  of  sour  ground.  The 
Quaking  Grass,  the  Bird's -foot 
Trefoil,  the  Burnet,  Hawkbit,  and 
Black  Knapweed  may  also  be 
considered  characteristic  of  poor 
land. 

In  meadows,  where  there  is  a 
certain  amount  of  moisture,  the 
Meadow  Saxifrage  may  be  found. 
It  is  abundant  in  several  parts  of 
England  and  southern  Scotland, 
but  is  rare  in  Ireland.  The  stems 
are  six  inches  to  a  foot  high,  the 
leaves  are  kidney-shaped,  and  the 
flowers  are  large  and  white.  It  is 
a  perennial. 

A  plant  characteristic  of 
meadows  or  pastures  on  clayey 
soil  is  the  Self-heal,  one  of  the 
Labiatae.  The  stem  is  creeping, 

the  flowering  branches  vary  in  height  from 

two  or  three  inches  to  six  or  eight ;    they 

are  seldom  a  foot  high.     The  flowers  are 

a  deep  purple. 

It  is  hardly  necessary  to  remark    that 

Buttercups     and    Daisies     together    with 

Grasses    and    Clovers    are    the    dominant 

plants  in  a  meadow.      In  moist  meadows 

the   Bulbous   and  the  Creeping  Buttercup 

are    the    two    most    common    species    of 

Ranunculus :    the   former    may    be    recog- 
nised   by   the    turned    back    sepals  ;    the 

latter    by    the    middle   lobe    of    the   leaf, 

which  projects  beyond  the  others  and  by 

the  creeping  stem.    The  Small  Daisy  (Bellis  FIG.  24.— Self-heal  (Prunella 

perennis)  grows  very  close  to  the  ground, 


FIG.  23. — Meadow  Saxifrage  (Saxifraga 
granulata). 


VEGETATION  OF  MEADOWS  AND  PASTURES        63 

and  flowers  nearly  the  whole  year  round  ;  the  large  Ox-eye  Daisy 
flowers  with  the  hay. 

The  plants  growing  in  a  meadow  have  certain  resemblances 
in  structure  ;  these  may  be  regarded  as  the  characters  by  which 
they  have  adapted  themselves  to  their  surroundings. 

1.  They  are  mostly  perennial.     This  is  true  of  most  of  the 
meadow  grasses,  and  it  is  interesting  to  note  that  where  a  grass 
is  naturally  an  annual,  as  the  Italian  Rye  Grass,  it  may  become 
a  perennial.     The  red  and  white  Clovers,  the  Bird's-foot  Trefoil, 
the  Buttercup,  the  Knapweed,  the  Yarrow  are  all  perennials. 

2.  Many  meadow  plants  have  something  of  the  nature  of 
creeping  underground  stems, — stolons,  or  rhizomes,  which  pro- 
duce a  carpet  of  vegetation. 

3.  The  leaves  are  thin,   flat,  broad,   and  smooth  ;  those  of 
the  meadow  grasses  have  stomata  on  both  sides,  and  they  never 
roll  up  as  those  of  xerophytic  grasses  do.     This  structure  of  the 
leaf  allows  of  free  transpiration  and  assimilation. 

In  Switzerland  the  Meadow  Plant  Communities  have  been 
classified  by  Schroter  according  to  the  type  of  meadow ;  thus 
u  dry  meadow,"  "  wet  meadow/'  etc.  Another  classification — 
and  one  to  be  preferred — is  based  on  the  dominant  grass  or 
dominant  plant  other  than  the  grass ;  thus  there  is  the  Festuca, 
the  Poa,  the  Agrostis  associations  among  the  grasses,  and  the 
Carex,  the  Orchis  among  other  flowering  plants.  In  Gloucester- 
shire, where  these  meadow  plant  associations  have  been  now 
observed  for  some  few  years,  it  is  found  that  in  certain  parts  of 
the  county  the  Cowslip  is  almost  absent ;  whilst  in  other  parts 
it  may  be  considered  the  dominant  plant,  and  associated  with 
it  in  many  meadows  is  the  Early  Purple  Orchis.  In  these 
meadows  we  should  have  a  Cowslip-Orchis  association ;  in 
some  parts  of  the  county  the  Daffodil  is  the  dominant  plant, 
not  the  Cowslip.  One  great  difficulty  in  mapping  out  Plant 
Communities  in  meadows  lies  in  the  fact  of  the  succession  of 
plants.  For  instance,  the  Early  Purple  Orchis  may  be  domi- 
nant in  spring  ;  a  month  or  two  later  the  Green-winged  Orchis 
may  be  the  dominant  species,  and  in  late  summer  yet  another 
group  of  plants  will  be  in  flower.  In  England,  very  little  work 
has  as  yet  been  done  on  Meadow  Plant  Communities. 


64  THE  BOOK  OF  NATURE  STUDY 

PASTURE  LAND. — It  is  difficult  to  draw  a  hard-and-fast  line 
between  a  meadow  and  a  pasture,  especially  in  this  country, 
where  the  same  land  may  be  grown  for  hay  in  one  year  and  the 
next  left  for  grazing.  There  seems  to  be  a  general  consensus 
of  opinion  that  land  which  is  mown  should  be  called  a  meadow 
and  that  a  pasture  is,  strictly  speaking,  land  which  is  grazed ; 
the  terms  "  mowing  meadow  "  and  "  grazing  meadow  "  have 
been  applied  to  land  that  is  both  mown  and  grazed.  Speaking 
generally,  a  pasture  is  higher  and  drier,  and  its  vegetation  is 
shorter  and  more  open  than  that  of  the  meadow. 

Farmers  often  speak  of  permanent  and  temporary,  or  seed, 
pastures.  Soil  which  is  too  light  to  maintain  a  good  pasture 
for  any  length  of  years  is  very  often  devoted  to  seed  pasture, 
and  in  the  present  condition  of  agriculture  it  is  considered  that 
the  best  system  of  farming  is  to  have  from  one-sixth  to  a  quarter 
of  the  land  thus  laid  down.  Permanent  pasture  is  land  which 
is  always  under  grass.  In  ecological  work  the  terms  "artificial" 
and  "natural  pasture''  are  more  generally  used.  Natural  pasture 
has  been  defined  as  primitive  grassland  without  heath  plants  ;  it 
is  permanent  pasture,  for  it  has  never  been  anything  else  but 
grazing  land.  Where,  however,  a  permanent  pasture  has  been 
-artificially  made,  as  when  land  originally  a  heath  or  moor  has 
been  converted  into  pasture,  it  would  from  the  ecological  point 
of  view  be  considered  artificial  pasture.  All  those  grazing  lands, 
with  the  ridge  and  furrow,  which  indicate  ploughed  land,  would 
come  under  the  term  "artificial  pasture."  The  fact  is,  that 
there  is  comparatively  little  natural  pasture  in  our  islands, 
especially  in  Scotland.  The  chalk  downs  of  Wiltshire,  the  oolitic 
limestones  of  the  Cotswolds,  and  the  Permian  limestones  are  the 
best  examples  in  England. 

A  good  grazing  pasture  should  have  its  surface  covered  with 
a  level  and  uniform  turf  of  nutritious  Grasses  and  Clovers  ;  there 
should  not  be  clumps  of  brown  herbage  here  and  there.  Grasses 
which  form  a  leafy  underground,  such  as  the  Sheep's  Fescue 
and  the  Meadow  Grass,  should  be  planted,  in  order  to  secure 
a  thick  "  bottom  growth,"  as  it  is  called.  Great  and  regular 
attention  has  to  be  paid  to  the  manuring  of  grazing  land.  If 
the  grasses  are  so  manured  as  to  produce  a  coarse  growth  they 


VEGETATION  OF  MEADOWS  AND  PASTURES       65 

will  be  less  nourishing.      Nitrogenous  manures  should  not  be 

applied  to  permanent  grazing  pastures.     If  the  animals  grazing 

on  them  are  fed  with  corn  and  oilcake,  then  it  is 

sufficient  to  supplement  the  animal  droppings 

with   some  non-nitrogenous  artificial   manure, 

such  as  kainit,  or  basic   slag.     Thistles  ought 

to  be  cut  down  twice  in  the  year,  directly  they 

appear  above  ground  in  the  spring  and  before 

the  time  of  flowering  in  the  late  summer ;    if 

they  gain  a  footing  in  a  pasture  they  deprive 

the  grass  of  nourishment.     The  ox  pastures  of 

Leicestershire    are    some    of    the    best   in    the 

country.      It   is    stated    that    all    the   manure 

they  receive  is  five  to  six  hundredweight  of 

common  salt  to  the  acre,  applied  in  the  autumn 

about  every  seventh  year.      Care   is  taken  to 

spread    the    animal    droppings   constantly,   in 

order  to  prevent  uneven  grazing. 

Natural  pasture  can  often  be  distinguished 
from  artificial  by  the  wild  plants  growing  on  it. 
Several  different  grasses  are  found  in  it,  and 
each  season  has  its  own  appropriate  flora,  so 
that  there  is  a  regular  succession  of  plants  re- 
placing each  other.  Further,  in  wet  years 
certain  plants  are  prominent  ;  in  dry  ones 
certain  others.  There  is  consequently  a  great 
deal  to  observe  in  the  vegetation  of  any  bit 
of  natural  pasture.  The  nature  of  the  soil, 
whether  hard  limestone,  or  chalk,  or  sand,  etc., 
should  be  noted ;  then  the  dominant  grass  to- 
gether with  the  sub-dominant  species ;  and 
lastly,  the  other  plants  belonging  to  each 
season  of  the  year.  The  plants  that  flower 
at  the  same  time  should  be  recorded,  and  it 
will  be  found  on  comparing  one  year  with  FIG.  25.— sheep's 

, ,  J.-L          i  •    /       i  i  i      Fescue  (Festuca  ovind). 

another    that    the    chief    plants   succeed  each 

other  in  a  regular  order.     The  colouring  of  the  pasture  at  each 

season  is  worth  noting  :    in  the  spring,  the  bright  green  of  the 

VOL.  V. 5 


66 


THE  BOOK  OF  NATURE  STUDY 


closely  cropped  grass  contrasts  strongly  with  the  sombre  colouring 
of  a  heather  moor,  or,  it  may  be,  with  the  rough  appearance 
of  a  grass  heath. 

The  natural  herbage  of  pastures  differs  considerably,  according 
to  the  nature  of  the  rock  or  soil  on  which  it  is  growing.  In  many 
localities  it  is  possible,  for  example,  to  contrast  the  pasture  of 
chalk  or  sandy  land  with  the  alluvium  or  clay  of  the  lower  levels. 
Much  useful  observation  may  be  made  and  intelligent  interest 
aroused  by  endeavouring  thus  to  correlate  the  character  of  the 
vegetation  with  that  of  the  soil.  Of  course,  some  plants  spread 
with  almost  every  type  of  soil,  but  others  will  be  found  restricted 
to  particular  kinds.  The  study  of  a  sandy  field  on  the  one  hand, 
and  a  chalk  pasture  on  the  other,  will  not  fail  to  prove  interest- 
ing and  instructive. 

LIMESTONE  PASTURE. — The  vege- 
tation of  dry  limestone  pastures 
includes  the  following  plants :  the 
most  common  grasses  are  the 
Sheep's  Fescue,  the  Fine  Bent  Grass, 
and  the  Cock's-foot.  Besides  these, 
Agrimony,  the  Woodrush,  Thyme, 
Milkwort,  Eyebright,  Salad  Burnet, 
Knapweed,  Hawkweeds,  Flax, 
Yellowwort,  and  certain  Orchids 
occur.  Ladies'  Fingers  (Anthyllis 
Vulneraria)  is  very  characteristic  of 
the  chalk  districts. 

The  Sheep's  Fescue  (Festuca 
ovina)  is  the  most  common  grass 
on  elevated  natural  pastureland  and 
mountain  slopes.  It  varies  con- 
siderably according  to  situation  and 
exposure,  being  sometimes  not  more 
than  two  or  three  inches  high,  while 
under  more  favourable  circumstances 
the  flowering  stems  may  reach  a  foot 
in  height.  It  is  a  densely  tufted 


FIG.  26.— Lady's  Mantle 
(Alchemilla  vulgaris). 


grass,  with  very  slender  leaves,  the 


VEGETATION  OF  MEADOWS  AND  PASTURES        67 


upper  ones  of  which  are  rolled.  The  spikelets  are  sharply  pointed, 
or  they  may  have  very  short  awns.  There  are  several  varieties 
of  this  grass,  and  it  is  not  easy  to  differentiate  them  (see  Fig. 
25).  The  Hard  Fescue  grows  taller  than  the  others,  and  belongs 
to  moister  soils ;  the  Red  or  Creeping  Fescue  has  red  sheaths  to 
the  lower  leaves,  and  belongs  to  poor,  stony  land. 

The  Field  Woodrush  (Luzula  campestris)  is  found  in  almost 
every  kind  of  pasture  land.  It  differs  from 
the  Common  Rush  (genus  Juncus)  in  its 
grasslike  leaves,  which  are  often  fringed 
with  a  few  long  white  hairs.  The  flowers 
of  this  species  are  six  or  eight  together  in 
clusters,  the  perianth  is  brown  with  bright 
coloured  shining  edges.  This  is  one  of  the 
first  plants  to  flower  in  pastures  in  spring  ; 
it  grows  low,  and  is  easily  distinguished 
from  the  surrounding  grass  by  the  brown 
colour  of  the  inflorescence.  The  Lady's 
Mantle  is  a  perennial  with  large  radical 
leaves,  which  form,  as  it  were,  a  small  cup 
or  saucer  that  contains  drops  of  rain  or 
dew.  The  rain  does  not  wet  the  leaf,  but 
touches  it  at  the  base,  where  a  tuft  of 
hairs  prevents  it  running  down  the  leaf- 
stalk. The  flowers  have  no  petals. 

The  Wild  Thyme  is  also  a  low  growing 
plant,  readily  recognised  by  its  character- 
istic scent  and  the  dense  tuft  of  purple 
flowers  covering  the  wiry  stems.  The 
flowers  are  two-lipped,  resembling  those 
of  the  Deadnettle  in  structure,  but  they  are' very  much  smaller. 
The  leaves  are  small  with  a  few  hairs  on  each  side.  It  flowers 
the  whole  summer  from  about  June  onwards. 

The  Flax  (Linum  catharticum]  is  a  very  characteristic  pasture 
plant.  It  has  a  slender  stem,  not  more  than  six  or  eight  inches 
high,  with  small  leaves  opposite  each  other,  and  small,  pure 
white  flowers  on  slender  stalks.  There  are  other  species  of  the 
genus,  such  as  the  flax  from  which  linen  is  obtained,  which  have 


FIG.  27.— Cathartic  Flax 
(Linum  catharticum). 


68 


THE  BOOK  OF  NATURE  STUDY 


pale  blue  flowers,  but  these  are  less  common,  although  they  too 

belong  to  limestone. 

An  interesting  plant,  on  account  of  the 
arrangement  of  its  leaves,  often  found  on 
oolitic  limestone,  is  the  Yellowwort.  The 
two  leaves  join  at  the  base  to  form  a  ring 
round  the  stem,  which  thus  appears  to  pass 
through  them.  They  are  greenish  grey  in 
colour,  and  the  flowers  a  bright  yellow.  The 
blossoms  are  closed  when  the  sun  is  not  shin- 
ing, and  they  remain  on  the  plant  long  after 
they  have  faded, — in  fact,  until  the  seed 
vessel  splits  them  up. 

Certain  Orchids  belong  to  pastures,  and 
very  often  to  a  limited  area  of  the  pasture. 
This  seems  to  be  a  characteristic  of  Orchids 
as  a  rule ;  they  are  often  abundant,  but  local. 
The  Spotted  Orchis  (0.  maculata)  is  common 
in  early  spring ;  in  summer  the  Frog  Orchis 
(Habenaria  viridis)  and  the  fragrant  Haben- 
aria  are  found  in  hilly  limestone  pastures. 
The  flower  of  an  Orchid  differs  in  many  re- 
spects from  other  flowers.  It  has  one  stamen 
which  is  united  with  the  ovary  ;  this  latter 
structure  is  usually  twisted,  and  appears  to 

be  at  first  sight  the  stalk  of  the  flower.     The 

pollen    grains   are    united  together  in    masses, 

which    adhere    to    the    insect's    proboscis     as 

they  are  touched.     This  is  easily  seen  by  in- 
serting a  sharp  pointed  pencil  into  the  spur  of 

the  corolla.     In  this  way  cross-pollination  takes 

place.      The   Frog;   Orchis  has  brownish   green 

u  j  i_  •    -L.J-    -      i-        !_•    i_       AU       FlG-    29.— Flower    of 

flowers,  and  grows  about  eight  inches  high;  the      anOrchid<  />Lower 


FlG.  28.— Yellowwort 
( Chlora  perfoliata). 


petal ;  /,  petals  ;  s, 
sepals  ;  //,  pollen 
bags. 


lip  petal    (labellum)   is  three -lobed   and   hangs 
straight  down ;  the  other  leaves  of  the  perianth 
arch  over  like  a  hood.     The  Fragrant  Haben- 
aria is  bigger,  and  may  be  even  two  feet  in  height.     The  purple 
flowers  are  borne  on  a  long  spike,  and  the  spur  of  the  lip  is 


VEGETATION  OF  MEADOWS  AND  PASTURES        69 

slender.  A  very  small  Orchid  found  in  September  on  limestone 
pastures  is  the  Autumnal  Lady's  Tresses  (Spiranthes  autumnalis). 
The  flowers  are  white  with  a  scent  of  almonds ;  the  leaves  are 
rosette-like,  and  not  more  than  an  inch  long. 

In  pasture  land  lately  reclaimed  from  muddy  salt  marshes, 
as  in  the  Levels  of  Somerset,  many  maritime  aquatic  plants  occur.. 
In  older,  drier  pastures  the  aquatic  plants  will  be  fewer,  and  the 
Field  Thistle  becomes  a  troublesome  weed. 

SANDY  PASTURE. — On  sandy  pastures 
the  Restharrow,  the  Stork's  Bill,  the  Stone- 
crop,  the  Heath  Bedstraw  (Galium  saxatile) 
and  patches  of  Gorse  are  the  most  char- 
acteristic plants. 

The  Restharrow  is  a  very  variable  plant. 
In  sandy  soil  it  is  more  thorny  than  when 
growing  inland ;  in  these  dry  situations 
many  of  the  small  branches  end  in  a  thorn. 
The  flowers  are  of  a  beautiful  pink  colour  ; 
the  "  standard  "  is  large,  and  the  filaments 
of  the  stamens  are  all  united  in  a  sheath. 

ALPINE  PASTURE — The  term  "  Alpine 
Pasture  "  is  usually  applied  by  botanists 
to  natural  pasture  which  is  situated  at  an 
altitude  of  over  2000  feet.  The  most 
abundant  grass  is  the  Blue  Moor  Grass,  so  FIG.  30.— Restharrow 
called  from  the  colour  of  the  spikes,  which 

get  a  bluish  tinge  in  a  congenial  habitat.  The  roots  descend  very 
deeply  into  the  soil,  in  order  that  the  grass  may  get  a  footing  and 
not  be  blown  or  washed  away  ;  the  stems  are  six  inches  to  a  foot 
high,  and  the  spike  of  flowers  about  an  inch  long.  The  stamens 
have  orange-yellow  anthers,  tipped  with  purple  ;  the  stigmas 
are  very  long.  The  time  of  flowering  varies  from  April  to  May 
or  June,  according  to  the  altitude.  Alpine  plants  are  found  along 
the  sides  of  streams  in  Alpine  pastures  ;  but  above  2000  feet, 
where  Alpine  pastures  are  situated,  vegetation  is  at  the  best 
scanty. 


^o  THE  BOOK  OF  NATURE  STUDY 

Sometimes  plants  which  belong  distinctly  to  the  lowland  are 
found  in  Alpine  pastures,  in  sheltered  spots  under  the  lee  of  rocks. 
Those  who  are  within  reach  of  the  fells  in  the  Lake  district 
might  keep  records  of  the  lowland  plants  found  above  2000  feet. 
The  following  list  is  given  by  Mr.  Lewis. 

Adoxa at  2480  feet. 

Wood  Sorrel   .        .'-'.'.         .         .        .  ,,  2500     ,, 

Herb  Robert ,,  2300     „ 

Water  Avens „  2250     ,, 

Wild  Angelica         ...  .  „  2100     „ 

Slender  St.  John's  Wort         .         .         .  „  2200     „ 

THE  DRAINAGE  OF  GRASSLAND. — The  level  of  the  ground 
water  is  of  great  importance  to  plants.  By  ground  water  is 
meant  the  layer  of  water  situated  above  some  impermeable  layer  ; 
for  instance,  a  sandy  or  gravelly  pasture  may  be  situated  on  a 
geological  layer  of  clay,  there  will  be  a  layer  of  ground  water 
between  the  pasture  and  the  clay.  The  level  of  this  ground 
water  varies  with  the  nature  of  the  soil,  and  to  some  extent  with 
the  season,  and  it  is  found  that  vegetation  varies  with  the  level 
of  the  ground  water.  Warming  quotes  Feilberg's  observations 
on  the  sandy  plains  near  Skagen  in  Jutland.  When  the  ground 
water  in  summer  is  at  a  depth  of  three  inches,  Juncus  vegetation 
and  meadow-moor  prevail ;  at  six  inches  Mosses  and  Sedges  are 
dominant,  but  Grasses  begin  to  occur  ;  at  nine  inches  these  are 
dominant ;  cereals  thrive  when  the  water  is  at  a  depth  of  from 
eighteen  to  twenty-four  inches  ;  at  from  thirty  to  forty,  Xerophytes 
reign. 

Drainage  is  essential  for  several  reasons.  If  soil  is  water-logged 
the  roots  are  confined  to  the  surface  layer ;  they  cannot  penetrate, 
for  they  must  have  air,  and  if  the  spaces  between  the  particles 
of  soil  are  filled  with  water  they  cannot  be  filled  with  air.  The 
following  experiment  shows  how  much  air  dry  soil  may  contain. 
Estimate  the  volume  of  a  glass  vessel  by  noting  how  many  cubic 
centimetres  of  water  are  necessary  to  fill  it.  Dry  the  vessel 
thoroughly,  and  fill  it  with  soil  which  has  been  thoroughly  dried 
in  the  sun  or  in  an  oven.  Then  pour  water  into  it,  noting  how 


VEGETATION  OF  MEADOWS  AND  PASTURES       71 

many  cubic  centimetres  the  soil  will  soak  up.  If  the  soil  is  dry  it 
will  be  found  that  it  takes  up  about  one-half  of  the  water  that  was 
poured  into  the  empty  vessel,  and  the  bubbles  of  air  can  be  seen 
coming  out  on  the  surface  as  the  soil  gets  thoroughly  soaked. 
Roots  cannot  penetrate  into  a  waterlogged  soil,  on  account  of  the 
want  of  air.  It  follows  that  in  a  season  of  drought,  when  the  level 
of  the  ground  water  will  be  altered,  that  plants  whose  roots  do 
not  extend  below  the  surface  will  suffer,  perhaps  even  die,  from 
want  of  water  ;  whereas  in  a  thoroughly  drained  soil  they  would 
have  penetrated  some  three  feet,  and  would  therefore  suffer  less 
from  the  drought.  Drainage  also  increases  the  temperature  of 
the  soil.  The  attention  paid  to  drainage  is  of  comparatively 
recent  date  in  many  districts.  Up  to  the  end  of  the  eighteenth 
century,  what  is  known  as  the  "  open-field  "  system  existed.  In 
Traill's  Social  England  an  open-field  farm  in  Wiltshire  is  thus 
described:  "  In  shape  it  was  generally  long,  narrow,  and  oblong, 
hemmed  in  between  the  downs  and  the  stream,  and  often  stretch- 
ing three  miles  in  length.  At  one  end  stood  the  cluster  of  mud- 
built,  straw-thatched  cottages,  each  with  its  yard,  or  small 
pasture,  for  horses,  calves,  or  field  oxen.  In  the  lowest  part  of 
the  land,  if  possible  along  the  banks  of  the  stream,  lay  the  per- 
manent meadows.  These  were  fenced  off  in  strips  and  balloted 
for  by  the  tenants,  and  held  in  separate  ownership  from  Candlemas 
or  from  Lady-Day  to  Midsummer  Day  or  hay  harvest.  As  soon 
as  the  grass  was  mown  and  the  hay  carried,  the  meadows  once  more 
became  open  common  pasturage,  and  so  remained  till  they  were 
once  more  allotted  and  put  up  for  hay.  Beyond  the  meadows 
lay  the  three  great  tillage  fields.  Each  of  the  three  fields  was 
cut  up  into  acre,  or  half-acre  strips,  divided  from  each  other 
by  narrow,  rough,  bush-grown  balks  of  unploughed  turf.  The 
complete  holding  of  each  village  was  so  distributed  that  each  man 
had  a  third  of  his  holding  in  each  of  the  three  fields.  Drainage  was 
impossible,  for  if  one  man  drained  his  land  or  scoured  his  courses 
his  neighbour  blocked  his  outfalls.  .  .  .  The  scab  was  rarely 
absent  from  the  common  fold,  or  the  rot  from  the  ill-drained 
field"  (vol.  v.  pp.  102-105). 

The    celebrated    grazier    Bakewell    was   one  of    the    first    to 
irrigate    his    meadows    about    the    middle    of    the    eighteenth 


72  THE  BOOK  OF  NATURE  STUDY 

century.  The  work  of  Arthur  Young  practically  put  an 
end  to  the  open-field  system.  It  is  estimated  that  between 
1830  and  1870  some  three  million  acres  of  heavy  land  were 
drained. 

The  present  appearance  of  rural  districts  with  pastures  and 
meadows  separated  from  each  other  by  hedges  is  entirely  different 
from  the  type  of  scenery  that  must  have  existed  when  the  "  open- 
field"  system  was  prevalent.  In  early  writers  there  is  no  mention 
of  hedges,  now  so  characteristic  a  feature  of  our  landscape. 
Under  the  Saxons,  meadowland  used  to  lie  open  from  hay  harvest 
to  the  following  spring.  When  the  grass  began  to  grow  the  cattle 
were  driven  out  and  the  meadow  fenced  round  and  divided  into 
as  many  equal  shares  as  there  were  families  in  the  village  ;  each 
man  had  his  own  haytime  and  housed  his  own  crop  ;  that  done, 
the  fences  were  thrown  down  and  the  meadow  became  again 
common.  Under  the  Normans,  the  open  fields  were  merely 
roughly  marked  off  by  turf  balks,  not  by  hedges.  The  first 
attempt  at  enclosing  the  waste  lands  of  the  manor  was  made 
in  Edward  Hi's  reign,  but  not  at  all  generally,  and  it  is  not  until 
the  sixteenth  century,  with  the  publication  of  Fitzherbert's 
Book  of  Surveying,  that  the  recommendation  to  cut  up  the 
land  into  small  fields,  each  surrounded  by  its  separate  hedge,  is 
definitely  recommended.  The  two  counties  that  adopted  this 
advice  were  Essex  and  Suffolk  ;  outside  these,  England  remained 
almost  totally  unenclosed  until  the  eighteenth  century.  The  state 
of  things  is  very  different  to-day.  The  fields  are  often  so  small 
and  the  hedges  and  the  hedgerow  trees  so  numerous,  that  a  good 
deal  of  land  is  incapable  of  profitable  cultivation.  In  very  small 
fields  with  large  trees  the  roots  of  the  trees  may  penetrate  so 
far  as  to  rob  the  crops  of  the  manure  intended  for  them.  They 
may  screen  the  sun  and  wind  too  much  from  the  hay  or  corn  that 
is  being  harvested.  They  prevent  satisfactory  drainage.  It  was 
calculated  about  thirty  years  ago  that  the  hedgerows  in  England 
and  Wales  occupy  not  less  than  one  million  and  a  quarter  acres  ; 
if  the  estimate  included  the  area  occupied  by  the  roots,  it  would 
be  three  millions. 

The  references  to  hedges  in  the  poetry  of  Wordsworth,  who 
wrote  many  of  his  nature  poems  during  the  last  years  of  the 


VEGETATION  OF  MEADOWS  AND  PASTURES        73 

eighteenth  century  or  the  beginning  of  the  nineteenth,  are  there- 
fore of  special  interest.  In  "  Tintern  Abbey  "  he  writes — 

"Once  again  I  see 

These  hedgerows,  hardly  hedgerows,  little  lines, 
Of  sportive  wood  run  wild." 

Does  this  denote  that  these  hedges  had  but  lately  been  planted 
in  1798,  the  date  of  the  poem?  In  "Margaret"  he  speaks  of 
"two  tall  hedgerows  of  thick  alder  boughs/'  and  in  "Lucy 
Gray"  of  "a  broken  hawthorn  hedge." 

At  the  present  time  the  Hawthorn  is  the  shrub  most  commonly 
planted  in  hedges  ;  the  Privet  is  also  common,  and  amongst 
hedgerow  trees  and  shrubs  may  be  mentioned  the  Elm,  the  Ash, 
the  Hazel,  the  Crab  Apple,  Elder,  Guelder  Rose,  Dogwood, 
Spindle  tree,  Rose.  In  autumn  the  berries  of  many  of  these  are 
conspicuous  from  their  bright  colouring,  which  attracts  birds,  and 
thus  the  seeds  are  dispersed.  The  haws  of  the  Hawthorn,  the 
hips  of  the  Rose,  the  dark  red  berries  of  the  Guelder  Rose,  the  red 
pod  of  the  Spindle-tree,  which  on  opening  exposes  the  orange- 
coloured  coat  of  the  seeds,  are  well  known  hedgerow  fruits.  Hedges 
are  sometimes  so  overgrown  that  it  is  difficult  to  say  whether 
the  dominant  plant  is  Hawthorn  or  some  other  shrub,  such  as 
Hazel ;  but  it  is  generally  possible  to  decide  if  a  sufficient  length 
of  hedge  is  examined.  The  plants  that  conceal  the  original  hedge 
are  mostly  climbing  The  Blackberry,  the  Clematis,  the  Con- 
volvulus, the  Vetches,  the  Woody  Night-shade,  in  order  to  get 
light,  clamber  up  to  the  top  of  the  hedge,  which  in  those  parts  of 
the  country  where  hedges  are  not  too  frequently  trimmed  is  a 
regular  tangle  of  climbing  plants.  Many  an  observation  may  be 
made  on  the  manner  in  which  the  plant  climbs,  whether  by  twisting 
its  stem  or  its  leaf-stalk,  or  by  prickles  or  by  the  development 
of  tendrils.  The  direction  of  twining  plants,  such  as  the  Black 
Bryony,  should  be  noted. 

The  herbaceous  vegetation  of  a  hedgerow  depends  on  several 
factors  : — 

i.  The  degree  of  moisture.  If  a  ditch  or  a  stream  is  situated 
at  the  bottom  of  the  hedgebank,  plants  which  like  a  damp  situation 
will  be  found.  (See  p.  40.) 


74  THE  BOOK  OF  NATURE  STUDY 

2.  The  degree  of  shade.     In  walking  along  a  country  lane 
the  hedgerow  plants  on  each  side  are  often  very  different.      In 
the  month  of  June,  on    the  shady  side  of  a  lane,  the  following 
plants  were  noticed  :  Germander  Speedwell,  Herb  Robert,  Hedge 
Garlick,  Black  Bryony,  Red    Campion,  Buttercup    (Ranunculus 
acris),  Bedstraws,  Stinging  Nettle,  Dog  Rose ;  whilst  on  the  oppo- 
site side  it  was  only  possible  to  find  the  Mouse-Ear  Hawkweed, 
Thyme,  a  species  of  Geranium,  and  the  common  Bird's-foot  Trefoil. 

3.  The  position  of  the  hedge  with  regard  to  the  pasture  or 
field  and  the  road.    The  vegetation  of  a  hedge  between  two  pastures 
does  not  vary  as  much  as  that  of  a  hedge  between  arable  land 
and  a  road.     The  weeds  of  arable  land  will  be  found  on  one  side  of 
such  a  hedge  ;  on  the  other  the  material  with  which  the  road  is 
mended  will  affect  the  plants  in  the  hedge,  for  it  alters  the  nature 
of  the  soil.     Thus  it  has  been  found  in  the  Fen  district,  where 
the  roads  are  often  repaired  with  chalk,  that  plants  foreign  to  the 
district  have  been  introduced.     As  a  rule  there  are  no  hedges 
in  the  Fen  country,  but  where  there  are  hedges  along  high  roads, 
as  in  the  western  and  midland  counties,  it  is  easy  to  note  the 
difference  in  the  vegetation  of  the  two  sides  of  the  hedge.     Where 
pastures  and  meadows  are  separated  by  stone  walls  instead  of 
hedges,  the  vegetation  is  xerophytic  in  character.     In  Cornwall, 
the  wall  flora  contains  many  not  very  common  plants,  such  as 
Valerianella,  Subterranean  Clover,  Field  Madder,  and  Trigonella. 

In    conclusion,    the    following    observations  on  pasture   and 
meadow  vegetation  may  be  suggested  :— 

1.  The  succession  of  Plant  Associations. 

2.  The  difference  of  the  time  of  flowering.     In  meadows,  kept 
for  hay,  the  plants  flower  more  or  less  together ;  in  pastures,  the 
time  of  flowering  is  different,  one  species  succeeding  another. 

3.  The  general  character  of  the  vegetation  in  each  case.     On 
the   whole,  that  of   the   pasture,   especially  if  natural  and  not 
artificial,  is  more  xerophytic  than  that  of  the  meadow. 

4.  The  hedgerow  vegetation.     The  difference  in  the  flora  of 
hedges  situated  between  two  meadows  or  pastures,  and  between 
a  road  and  a  pasture  or  meadow,  is  worth  noting. 

BIBLIOGRAPHY. — A.  D.  Hall,  Rothamsted  Experiments  ;  Buchanan,  A  Country 
Reader.     Part  II. 


?•;  •' .-,-—      .; 


CHAPTER  IV 

THE  WEEDS  OF  CULTIVATION 

IN  walking  over  such  tracts  of  country,  as  the  South  Downs,  it 
is  possible  to  notice  traces  of  the  ridge  and  furrow,  which  possibly 
point  to  the  fact  that  at  one  time  the  land  was  under  the  plough. 
In  the  thirteenth  and  fourteenth  centuries  there  could  not  have 
been  much  less  Wheat  grown  than  there  is  at  present,  and  there  may 
have  been  more  ;  for  in  those  days  the  population  was  fed  on  the 
food  grown  in  England  and  wheaten  bread  formed  a  considerable 
part  of  the  peasant's  diet.  Towards  the  end  of  the  fourteenth, 
and  during  the  fifteenth,  century,  when  wool  was  very  much  in 
demand  and  labour  scarce,  the  acreage  of  land  devoted  to  pasture 
increased  considerably.  Sheep-keeping  was  at  that  time  the  most 
profitable  part  of  farming.  In  1436  the  growing  of  corn  had  so 
decreased  that  politicians  became  alarmed,  and  an  Act  was  passed 
to  keep  up  the  price  of  corn  and  thus  encourage  tillage.  Up  to  the 
end  of  the  eighteenth  century,  wool  was  one  of  the  chief  sources  of 
profit  to  the  English  farmer,  and  England  was  then  mainly  a 
pasture  country. 

The  work  of  Arthur  Young  in  agriculture,  coinciding  as  it  did 
with  the  industrial  revolution  that  was  taking  place  owing  to  the 
introduction  of  machinery  in  manufacturing  districts,  rapidly 
changed  the  methods  of  farming.  Waste  land,  and  much  of  the  land 
that  had  been  held  in  common,  was  brought  under  wheat  cultiva- 
tion. Prices  fluctuated  during  the  Napoleonic  wars  from  about 
635.  to  1155.  the  quarter.  In  those  days  it  paid  to  grow  wheat. 
With  the  beginning  of  the  nineteenth  century  may  be  compared 
its  closing  years,  which  witnessed  a  remarkable  shrinkage  in  the 
amount  of  wheat  grown.  In  1871  there  were  in  England  three 
and  a  quarter  million  acres  under  wheat ;  in  1901,  only  about  a 
million  and  a  half.  England  is  now  dependent  on  other  countries 
for  her  food  supply,  and  is  again  mainly  a  pasture  country. 


75 


76 


THE  BOOK  OF  NATURE  STUDY 


Wheat  is  grown  successfully  when  the  average  July  temperature 
is  at  least  56°  F.  and  the  rainfall  below  thirty-three  inches.  More 
wheat  is  grown  in  England  than  in  Scotland  ;  more  in  the  south 
than  in  the  north.  The  line  of  the  northern  limit  of  wheat  passes 
through  Britain.  There  is  also  a  well-marked  limit  in  altitude, 
but  this  varies  with  the  slope  of  the  hills.  Mr.  R.  Smith  gives 
five  hundred  feet  as  the  limit  on  the  northern  slopes  of  the  Pent- 

lands  near  Edinburgh,  and  seven  hundred 
on  the  south-eastern  slopes;  in  Yorkshire, 
wheat  grows  well  at  an  altitude  of  six  or 
seven  hundred  feet. 

WHEAT,  AN  "  INDICATOR  "-PLANT.  —  In 
ecological  observations  Wheat  has  been 
taken  as  an  indicator-plant.  It  is  found, 
for  instance,  that  certain  trees  and  weeds 
do  not  ascend  higher  than  the  Wheat  line. 
It  has  been  observed  that  the  lowland  oak 
woods  within  the  Wheat  zone  have  a 
richer  vegetation  than  oak  woods  above 
the  Wheat  limit.  The  same  holds  good 
with  the  weeds  of  arable  land.  Of  sixty- 
three  out  of  one  hundred  weeds  found  in 
Yorkshire  to  be  common  to  arable  land, 
only  forty-two  occur  above  the  Wheat 
line.  The  Common  Poppy,  the  Wild 
Radish,  Field  Pansy  (Viola  arvensis),  the 
Corn  Cockle,  Sow-Thistle,  Spurge,  Shep- 
herd's  Needle  are  some  of  the  most  pro- 
minent  in  the  wheat  zone.  Certain  aquatic 
plants,  such  as  the  Bur-reed  (Typha  lati- 

folia)  and  the  Common  Reed  (Phragmites  communis)  are  distributed 
over  the  same  area  ;  whilst  others  belong  entirely  to  marshy 
ground,  where  wheat  cannot  be  grown.  The  Corn  Cockle  (Lychnis 
Githago)  is  a  remarkably  handsome  plant,  with  a  peculiar  calyx, 
which  has  long,  green  linear  lobes  projecting  beyond  the  petals. 
The  fruits  of  the  Wild  Radish  and  the  Pansy  are  worth  noticing  : 
that  of  the  Radish  is  jointed  by  transverse  partitions  into  as  many 


FIG.SI.—  Corn  Cockle  (£ydfc 
Githago}. 


THE  WEEDS  OF  CULTIVATION 


77 


portions  as  there  are  seeds,  and  it  dehisces  transversely ;  that  of 
the  Pansy  also  opens  to  let  out  its  seeds,  and  splits  at  the  midrib 
into  three  valves,  each  containing  a  row  of  seeds,  which  are  forced 
out  several  feet  by  the  walls  of  the  valve  coming  together  as  the 
fruit  gets  dry.  The  Shepherd's  Needle  is  in  some  respects  unlike 
most  of  the  Umbelliferse.  It  is  sometimes  called  Venus'  Comb, 
from  the  shape  of  the  fruit,  which  is  nearly  two  inches  long 
and  resembles  a  comb,  the  edges  being 
fringed  with  teeth. 


FIG.  32.— Shepherd's  Needle  (Scandix 
Pecteri). 


FIG.  33.— Black  Medick 
(Medicago  lupulind). 


In  discussing  the  weeds  of  arable  land  it  is  almost  impossible 
to  say  which  weeds  are  associated  with  any  particular  crop,  for 
at  the  present  time  there  is  a  regular  rotation  of  some  three  or 
four  crops  on  all  cultivated  land.  At  Rothamsted  Experimental 
Station,  however,  a  certain  field  has  been  grown  continuously  in 
wheat  for  more  than  fifty  years,  and  the  weeds  that  havegiven  most 
trouble  on  the  unmanured  plots  are  the  Black  Bent  Grass  (Alo- 
pecurus  agrestis]  and  the  Black  Medick.  Of  those  two,  the  Bent 
Grass  is  by  far  the  greater  pest ;  the  Black  Medick,  indeed,  is  of 


78  THE  BOOK  OF  NATURE  STUDY 

some  use,  for  being  a  leguminous  plant  it  enriches  the  soil  with 
nitrogen,  and  may  in  this  way  help  to  supply  the  want  of  manure. 
In  appearance  it  is  not  unlike  the  small  yellow  Clover,  but 
may  be  distinguished  from  it  by  the  fruit,  which  is  black  and 
spirally  twisted.  Another  difficulty  in  associating  certain  weeds 
with  particular  crops  is  caused  by  the  impurity  of  seed.  Weeds 
are  constantly  introduced  with  the  seed  sown.  Thus  Charlock,  so 
common  in  Potato,  Corn,  and  other  tields,  has  a  seed  very  like  that 
of  the  turnip  or  rape,  and  might  be  easily  introduced  with  either 
crop  ;  the  Dodder  is  so  often  mixed  with  Clover  that  in  England 
an  ounce  of  Dodder  in  a  ton  of  clover  is  considered  permissible. 
In  most  continental  countries  there  are  seed-testing  stations  under 
Government  control,  in  order  to  test  the  germinating  power  of  the 
seed,  and  to  ensure  its  purity  and  genuineness.  This  is  of  great 
practical  use  to  the  farmer,  for  if  he  knows  that  the  seed  he  is 
sowing  has  only  a  germinating  value  of  75  per  cent,  instead  of  95, 
he  can  increase  the  quantity  sown  in  a  given  area  and  thus  save 
loss.  At  the  seed  station  in  connection  with  the  Royal  College 
of  Science,  Dublin,  some  fifteen  hundred  samples  a  year  are  tested, 
and  the  quality  of  the  flax  seed  sown  in  Ireland  has  distinctly 
improved  since  the  establishment  of  the  station. 

ROTATION  OF  CROPS. — The  rotation  of  crops  in  farming  is  due 
to  the  fact  that  different  plants  make  a  different  demand  on  the 
soil.  There  are  certain  substances  that  all  plants  require  for  food  ; 
some  are  obtained  from  the  air,  others  from  the  soil,  but  the 
quantity  required  by  each  plant  varies.  Clover  needs  a  great  deal 
of  potash,  wheat  comparatively  little  ;  on  the  other  hand,  wheat 
needs  silica.  As  long  as  the  "  open-field  "  system  lasted  it  was 
impossible  to  have  a  rotation  of  crops,  in  which  roots,  such  as 
Turnips,  should  form  an  element.  Up  to  the  end  of  the  eighteenth 
century  each  village  farm  had  attached  to  it  three  great  tillage 
fields,  and  the  usual  practice  was  to  sow  one  with  Wheat  or  Rye  ; 
the  second  with  Barley,  Oats,  Beans  or  Peas,  whilst  the  third  lay 
fallow.  Thus,  even  then,  there  was  a  rotation  of  crops,  but  a 
limited  one.  Arthur  Young,  writing  in  1768,  remarks  that  Clover 
and  Turnips  were  unheard  of  in  many  parts  of  the  country,  and 
even  as  late  as  1811  they  were  still  almost  unknown  in  Wiltshire. 


THE  WEEDS  OF  CULTIVATION  79 

Now  roots  form  a  regular  element  in  the  rotation  of  crops  ;  the 
order,  however,  varies  in  different  parts  ;  in  Norfolk,  Turnips  are 
followed  by  Barley,  Barley  by  Clover,  and  Clover  by  Wheat. 

In  order  to  ascertain  the  substances  that  a  plant  requires  for 
food,  its  ash  maybe  analysed.  Then  the  soil  in  which  it  is  proposed 
to  grow  it  should  also  be  analysed,  and  any  deficiency  of  the 
substances  necessary  to  the  plant  should  be  made  good  by  appro- 
priate manure.  The  amount  of  humus  in  soil  may  be  ascertained 
by  first  drying  and  weighing  the  soil,  then  burning  it,  and  weighing 
again.  By  means  of  sieves,  with  meshes  of  a  different  size,  the 
amount  of  silt-clay,  gravel,  and  sand  can  be  roughly  estimated. 
Silt-clay  passes  through  a  mesh  of  0-05  mm.,  leaving  the  sand  and 
gravel  in  the  sieve.  This  residue  is  then  sifted  in  a  sieve  with  a 
mesh  of  i  mm.,  the  sand  passing  through  whilst  the  gravel  remains. 
A  definite  weight  of  dried  soil  must  be  taken  to  begin  with,  and  at 
each  stage  the  residue  must  be  dried  and  weighed.  In  this  way 
the  percentage  of  sand,  clay,  etc.  can  be  determined.  The  terms 
"  marl  "  and  "  loam  "  are  constantly  used  in  any  rough  classifi- 
cation of  soils.  A  marl  is  a  mixture  of  lime  and  clay  ;  a  loam,  of 
clay  and  sand. 

All  good  soils  contain  a  certain  amount  of  clay,  which  is  richer 
in  plant  food  than  any  other  part  of  the  soil,  and  it  also  has  the 
power  of  fixing  certain  substances  required  by  the  plant.  Clay 
also  retains  water,  and  needs  good  drainage  and  admixture  with 
sand,  or  lime,  or  ashes,  etc.  to  increase  its  porosity. 

CERTAIN  WEEDS  CHARACTERISTIC  OF  CERTAIN  SOILS. — The 
majority  of  plants  seem  able  to  grow  on  most  soils,  provided  they 
can  get  the  water  they  require.  This  seems  to  show  that  it  is  the 
physical,  rather  than  the  chemical,  properties  of  the  soil  which  are 
of  the  greatest  importance  to  the  plant.  The  one  exception  to  this 
rule  is  lime,  which  many  plants  appear  either  to  love  or  hate ;  it  is 
for  this  reason  that  it  is  preeminently  possible  to  speak  of  a  chalk 
flora.  On  light  calcareous  soils  it  is  found  that  Sainfoin  and 
Lucerne  are  valuable  crops  for  purposes  of  fodder.  Amongst  the 
weeds,  which  are  commonly  found  on  soils  with  a  good  proportion 
of  calcium  carbonate,  may  be  mentioned  Fumitory  (Fumaria 
officinalis)  and  the  Dove's-foot  Geranium  (G.  molle). 


So 


THE  BOOK  OF  NATURE  STUDY 


Fumitory  is  characteristic  of  cornfields,  and  is  easily  recognised 
by  the  very  delicate  leaves  and  irregular,  curiously  formed  pink 

flowers,  tipped  with  purple.  The  leaf- 
stalks act  the  part  of  tendrils,  and  coil 
round  the  stems  of  adjacent  plants. 
Each  flower  has  two  sepals,  which  soon 
fall  off.  There  are  four  petals,  the 
upper  one  being  prolonged  into  a  spur, 
the  two  inner  ones  being  joined  to- 
gether at  the  tip.  The  six  stamens  are 
arranged  in  two  bundles  of  three  each. 
Geranium  molle  has  downy  leaves  and 
small  pink  flowers  with  deeply  notched 
petals ;  the  flower-stalks  are  shorter 
than  the  leaves,  and  each  bears  two 
flowers. 

Many  leguminous  plants  do  not 
grow  well  on  sandy  soils ;  Lupins  and 
Gorse  are  exceptions.  The  barren 
sandy  heaths  of  East  Prussia  have 
been  reclaimed  and  rendered  fit  for 
cultivation  by  growing  Lupins  and 
ploughing  in  the  green  crop.  At  the  Royal  Agricultural 
Society's  farm  at  Woburn  the  experiments  made  with  Gorse 
on  the  coarse  sandy  soil  seem  to  show  that  it  might  become  a 
valuable  fodder  crop.  In  ecological  work,  the  presence  of  Gorse 
may  almost  invariably  be  taken  as  indicative  of  a  sandy  layer 
of  soil,  even  where  the  underlying  geological  layer  is  of  a  different 
character.  Amongst  crops,  Potatoes  and  Carrots  are  best 
adapted  for  sandy  soils,  provided  sufficient  manure  is  given.  The 
most  common  weeds  of  these  soils  are  the  Poppy,  the  Spurreys, 
and  the  Cornflower.  The  bright  scarlet  blossoms  of  the  Poppy, 
the  blue  Cornflowers,  and  the  pink  Sand-Spurrey  form  a  striking 
contrast  to  the  yellow  Corn.  There  are  two  species  of  Poppy : 
the  Common  Field  Poppy  (Papaver  Rhceas}  has  flowers  of  a  deeper 
colour  than  those  of  the  long-headed  species  (P.  dubium)  ;  but 
the  chief  difference  is  in  the  fruit,  which  is  much  shorter  and 
stouter  than  that  of  P.  dubium.  The  unfolding  of  the  petals, 


FIG.  34. — Fumitory  (Fumaria 
officinalis). 


THE  WEEDS  OF  CULTIVATION  81 

which  have  been  crumpled  in  bud,  is  worth  watching  ;  they  look 
so  tumbled  when  the  sepals  first  open,  yet  they  spread  themselves 
out  perfectly  smoothly.  The  opening  of  the  fruit  by  pores  just 
below  the  lid  formed  by  the  stigmas  should  also  be  observed  ;  the 
seeds  are  thrown  some  distance  from  the  parent  plant,  and  thus 
dispersed. 

The  Cornflower  has  very  large  outer  florets,  whose  work  it  is 
to  attract  insects.  The  inner  disc  florets  are  the  perfect  ones, 
making  both  pollen  and  seed.  Another  of  the  Compositae,  common 
in  cornfields  on  sandy  as  well  as  calcareous  soil,  is  the  Corn  Marigold, 
in  which  all  the  florets  are  of  a  deep  golden  yellow.  This  belongs 
to  the  same  genus  as  the  Ox-eye  Daisy,  but  does  not  grow  as  large 
and  has  not  white  florets.  The  Corn  Spurrey  (Spergula  arvensis) 
grows  about  six  or  eight  inches  high.  It  has  very 
narrow  leaves,  apparently  whorled,  and  very  minute 
white  flowers  with  undivided  petals.  The  Sandwort 
Spurrey  (Spergularia  rubra)  is  found  near  the  sea. 
It  is  a  more  creeping  plant  than  the  other,  and 
usually  has  pink  flowers. 

Certain  weeds  are  characteristic  of  rich  loams. 
The  most  common  are  the  Groundsel,  the  Chick-   FlG  35.^.A  floret 
weed,    the    Sowthistle,   two   or   three   species    of      of  Groundsel, 


Veronicas,  a  species  of  Spurge  (Euphorbia  Peplus\      cal^  ;  °*  ovar>r  ; 

A  ^     TV  IT?  i  4.1,     r  A     i          J/»    stigmas  ;    «, 

and  the  Pimpernel.  Every  one  knows  the  Groundsel,  staminai  tube. 
which  is  practically  ubiquitous.  There  are  seldom 
any  ray-florets,  all  the  flowers  being  tubular.  The  involucre 
consists  of  two  rows  of  bracts  tipped  with  black,  the  outer  row 
being  shorter  than  the  inner  one.  The  calyx,  as  in  most  of  the 
Compositae,  is  represented  by  hairs,  which  form  the  feathery 
pappus  after  the  flower  has  withered.  The  petals  and  stamens 
are  five  in  number,  and  the  stamens,  being  joined  together  by 
their  anthers,  form  a  tube  through  which  the  stigmas  pass.  Self- 
pollination  takes  place  as  the  stigmas  are  pushing  their  way  up 
through  the  staminai  tube  ;  the  stamens  dehisce  inwards  and 
the  pollen  grains  fall  on  the  stigmas.  Small,  inconspicuous 
flowers  of  this  kind  are  not,  as  a  rule,  dependent  on  cross- 
pollination,  although  this  may  take  place  occasionally. 

The  Chickweed  (Stellaria  media}  is  almost  as  common  as  the 

VOL.  V.  —  6 


82 


THE  BOOK  OF  NATURE  STUDY 


Groundsel.  It  is  found  in  allotments,  and  practically  in  all  fairly 
rich  cultivated  ground.  It  may  be  distinguished  from  other 
Chickweeds  by  the  ovate  leaves  and  by  the  hairy  line  which  runs 
along  its  stem,  shifting  from  side  to  side  at  each  node. 

The  Sowthistle  (Sonchus  arvensis}  is  common  in  cornfields,  and 
may  be  recognised  by  the  long,  lanceolate  leaves,  curved  down- 
wards and  bordered  by  small  prickly  teeth.  The  flower-heads 
are  large,  of  a  bright  yellow.  A  still  more  common  weed  of  arable 

land  is  another  species  (Sonchus  oleraceus), 
which  has  rather  smaller  flower-heads  with 
pale  yellow  florets. 

The  Speedwell  most  commonly  found  in 
cultivated  ground  is  Veronica  agrestis,  which 
may  be  distinguished  from  other  species 
most  closely  resembling  it  by  the  narrow 
sepals  and  the  white  lower  petal  of  the 
corolla.  In  allotments  the  Germander 
Speedwell,  the  largest  of  the  Veronicas,  is 
common.  The  structure  of  the  flower 
should  be  examined,  for  in  many  respects 
it  differs  from  the  other  genera  of  the 
Scrophulariaceae.  There  are  only  four 
petals  and  two  stamens,  which  are  placed 
laterally.  The  complete  number  of  stamens 
in  this  order  is  five,  as  in  Mullein  ;  many 
genera,  however,  have  only  four,  and  in 
some  cases,  as  in  the  Figwort,  a  scale  re- 
presents the  fifth  stamen.  The  reduction  of 
stamens,  from  six  to  two,  reaches  its  lowest  limit  in  the  Speedwells. 
The  lower  petal  is  generally  larger  than  the  others,  and  forms  a 
landing-place  for  the  flies  which  pollinate  the  flower.  The  stigma 
stands  straight  up  in  the  middle  of  the  flower,  and 
is  touched  by  the  fly  before  the  stamens,  and  by  a 
different  part  of  its  body.  In  trying  to  get  the 
honey,  which  is  secreted  by  the  gland  below  the 
ovary,  the  insect  comes  in  contact  with  the  stamens, 
from  which  it  gets  the  pollen  to  carry  to  another 
flower.  The  Scarlet  Pimpernel  (Anagallis  arvensis) 


FIG.  36. — Germander 
Speedwell  (  Veronica 
Chamcedrys). 


FIG.  37.— Fruit 
of  the  Scarlet 
Pimpernel. 


THE  WEEDS  OF  CULTIVATION 


is  found  in  cornfields,  creeping 
along  the  ground.  When  the  corn 
has  been  cut,  the  plant  is  in  fruit, 
and  its  dehiscence  should  be  noted. 
It  splits  transversely,  allowing  the 
top  to  be  lifted  off  like  a  lid.  The 
majority  of  capsules  split  longi- 
tudinally, therefore  this  transverse 
dehiscence  is  interesting.  The 
bright  scarlet  flowers  expand  only 
in  fine  weather,  hence  the  name 
Poor  Man's  Weather-glass  has  been 
given  to  the  plant.  The  Petty 
Spurge  (Euphorbia  Peplus)  is  an 
annual.  The  peculiarity  of  structure 
in  the  Spurges  is  that  each  appar- 
ent stamen  is  a  flower,  for  each 
has  a  minute  scale  at  its  base.  The 
cup-shaped  structure,  which  at  first 
sight  may  easily  be  taken  for  a  . 

FIG.    38.  —  Petty    Spurge    (Euphorbia 

corolla,   is   an  involucre   furnished     pepius\  s,  Staminate  flowers  •,  p,  Pis- 

with    four    Or    five    teeth    and   with       tillate  flower  ;  g,  glands  ;  *»,  involucre. 

brownish  yellow  glands.  The  pistillate  flower 
in  the  centre  has  a  three-celled  ovary ;  the 
styles  are  three,  and  the  whole  flower  hangs 
down.  In  the  Spurges  then,  what  appears  to 
be  a  single  flower  is  an  inflorescence.  All  the 
Spurges  have  a  milky  juice  which  is  often 
poisonous.  Many  well-known  foods  are  pre- 
pared from  plants  belonging  to  this  order. 
Tapioca  comes  from  the  West  Indian  Cassava. 
There  are  two  species  of  Cassava  common  in 
the  West  Indies.  The  root  of  the  Sweet 
Cassava  is  eaten  as  a  vegetable  ;  the  Bitter 
Cassava  is  highly  poisonous,  but  a  flour  is 
prepared  from  it  by  extracting  all  the 
poisonous  juice,  and  out  of  this  the  thin 

Fir,  39.— Field  Pennycress   £  J,  ,.,         ... 

i  arveme)         Cassava  cakes,  which  visitors  to   the  West 


84 


THE  BOOK  OF  NATURE  STUDY 


Indies  know  so  well,  are  made.  The  Croton  plants  and  the 
Castor-oil  plant  belong  to  the  same  order,  the  Euphorbiaceae. 

In  walking  by  the  edge  of  an  oat-field  one  of  the  most  conspicu- 
ous plants  in  the  month  of  June  is  the  Bladder  Campion  ;  its  white 
blossoms  stand  out  strikingly  against  the  yellow  Corn.  It  resembles 
the  White  Campion,  but  differs  from  it  in  the  swollen  bladder-like 
calyx,  and  its  flowers  are  open  during  the  day,  whilst  the  White 

Campion  (Lychnis  vesper- 
tina)  does  not  open  until 
the  evening. 

The  Penny  cress  (Thlaspi 
arvense)  is  also  a  denizen  of 
cornfields.  The  fruits  are 
massed  together  in  a  long 
raceme,  each  capsule  has  a 
very  broad  wing,  reminding 
one  a  little  of  the  garden 
Honesty.  The  wing  is  deeply 
notched  at  the  top,  and  there 
is  a  minute  style  in  the 
notch.  (See  Fig.  39.) 

On  clay  soils  the  Corn 
Buttercup  (Ranunculus  ar- 
vensis)  is  very  common  in 
cornfields  ;  it  is  also  found 
abundantly  on  calcareous 
soils.  The  special  feature 
of  this  plant  is  its  fruit, 
which  distinguishes  it  from 

:orn  Buttercup  (Ranunculus  ar^ensis}.    ^   Qther   spedes   Qf    Ramm_ 

culus.  The  carpels  are  prickly.  The  Field  Mint  (Mentha  arvensis) 
is  also  troublesome  on  clay  soils.  As  a  rule  weeds  are  not  so 
numerous  on  clay  soils  as  on  many  others,  owing  to  the  close 
texture  of  the  soil.  In  good  seasons,  that  is,  when  there  is  a 
certain  amount  of  rain,  so  that  the  clay  does  not  get  hard  and 
dry,  some  crops,  especially  Beans,  Mangolds,  and  Wheat,  do  very 
well.  If  the  season,  however,  is  very  dry  the  plants  are  in  danger 
of  not  getting  enough  water  from  the  subsoil,  and  then  their 


THE  WEEDS  OF  CULTIVATION 


growth  is  stopped  and  the  crop  is  poor.  A  weed  that  is  often 
found  in  great  quantities  along  the  edge  of  a  Bean-field  is  the 
Gromwell  (Lithospermum  arvense).  This  plant  grows  about  a  foot 
high,  and  is  covered,  as  the  majority  of  the  Boraginacese  are, 
with  hairs.  The  flowers  are  small  and  white,  and  the  nut-like 
fruits  very  hard. 

The  number  of  weeds  found  in  cultivated  land  is  said  to  be 
about  280.  Of  these,  only  about  100 
are  found  above  the  limit  of  Wheat 
cultivation,  i.e.  above  500  feet  in  the 
Highlands.  Many  of  the  species  which 
belong  to  the  Wheat  zone  cease  to  be 
prominent  above  the  Wheat  line,  and 
become  casuals.  If  seed  grain  from 
another  district  is  used,  weeds  are 
often  imported  with  it,  and  may, 
under  these  circumstances,  spread 
from  a  lower  to  a  higher  altitude, 
holding  their  own  for  a  time,  but 
they  cannot  stand  the  stress  of  com- 
petition and  soon  die  out.  Light, 
calcareous  soils  are  apt  to  be  more 
weedy  than  clay,  or  sandy,  soils. 

The  only  classification  of  weeds  of 
arable  land  that  can  be  given  in  the 
present  state  of  our  knowledge  is 
based  on  soils  ;  for,  as  has  been 
already  said,  the  only  way  of  ascer- 
taining whether  there  is  a  relation 
between  the  crop  and  the  weeds 
would  be  by  having  experimental  plots,  planted  year  after 
year  with  the  same  crop,  to  which  the  same  kind  of  manure 
was  given  season  after  season.  It  is,  indeed,  possible  to  give 
the  weeds  belonging  to  the  Wheat  zone  ;  but  it  must  be  re- 
membered that  this  includes  at  least  two  or  three  crops  in 
addition  to  Wheat. 

The  following  lists  are  not  meant  to  be  mutually  exclusive  ; 
some  weeds,  such  as  Groundsel,  Shepherd's  Needle,  and  Chickweed 


FlG.  41. — Corn  Gromwell  (Litho- 
spermum arvense}. 


86 


THE  BOOK  OF  NATURE  STUDY 


(Stellar ia  media)  grow  almost  everywhere.  Many  of  those  given 
as  belonging  to  calcareous  soils  are  also  found  on  loams,  and  vice 
versa.  Of  course,  in  actual  practice  the  result  of  adding  lime  and 
manures  to  arable  soils  is  to  modify  the  "  weed  flora  "  that  they 
bear. 

CLASSIFICATION  OF  SOME  COMMON  WEEDS  ACCORDING  TO  SOIL. 


SANDY  SOILS. 

CLAY  SOILS. 

LOAMS. 

CALCAREOUS  SOILS 

Cornflower 

Black  Bent  Grass 

Chickweed 

Fumitory 

Corn  Marigold 

Field  Mint 

Groundsel 

Dove's-foot  Gera- 

Spurrey 

Wild  Carrot 

Stinking  Mayweed 

nium 

Sandwort  Spurrey 

Corn  Buttercup 

Sowthistle 

Convolvulus  Poly- 

Horsetail 

Goose  Grass 

gonum 

Field  Speedwell 

Bladder  Campion 

Wild  Poppy 

Scabious 

Petty  Spurge           i  Shepherd's  Needle 

Pimpernel 

Radish 

Henbit 

Poppy 

Chicory 

PRACTICAL  OBSERVATIONS. — Arable  land,  if  left  uncultivated, 
would  revert  to  heath.  The  first  stage  would  probably  be  a 
return  to  rough  grass  occurring  in  patches,  together  with  such 
plants  as  Ragwort  and  Crosswort.  The  former  plant  sometimes 
establishes  itself  to  the  exclusion  of  any  other.  If  the  soil  is 
sandy  the  Grass  associations  might  in  time  be  conquered  by 
Bracken  and  then  by  Heather.  As  was  seen  in  the  last  chapter, 
natural  pasture  may  be  defined  as  grassland  without  heath  plants. 
If  uncultivated  arable  land  reverts  to  grassland  it  is  practically 
only  a  step  further  back  to  grass  heaths,  and  thence  to  heather 
moors,  or  woodland.  Thus  the  vegetation  of  a  district,  if  undis- 
turbed by  man  and  animals,  is  always  changing,  one  species  after 
another  being  ousted,  until  at  last  the  one  best  adapted  to  the 
environment  creeps  in  from  elsewhere,  establishes  itself,  and 
holds  its  own.  It  is  the  purpose  of  vegetation  maps  to  register 
some  of  these  changes. 

In  making  observations  on  arable  land,  the  extent  to  which 
Wheats  and  Oats  are  cultivated  should  be  noted.  In  Scotland, 
Oats  are  grown  wherever  land  is  cultivated  at  all.  An  altitude 


THE  WEEDS  OF  CULTIVATION  87 

of  1250  feet  is  reached  in  the  Highlands,  and  in  some  parts  there 
are  traces  of  former  cultivation  as  high  as  1500  feet.  A  list  of 
weeds  in  the  Wheat  zone,  and  of  those  in  the  Oat  zone,  might  be 
made  ;  it  will  be  found  that  some  are  found  at  the  higher  altitude 
of  the  Oat  belt  which  are  not  present  in  the  lower  Wheat  area.  A 
map,  with  the  height  above  the  sea  level  marked,  could  be  drawn 
and  the  Wheat  and  Oat  fields  inserted,  and  coloured  to  show  the 
difference  in  the  altitude  at  which  the  two  crops  will  grow. 

The  effect  of  farming  operations  on  weeds  and  their  influence 
on  the  Plant  Associations  that  occur  would  form  an  interesting 
series  of  observations  from  year  to  year.  To  get  approximately 
accurate  results,  it  would  be  necessary  to  keep  records  of  the 
ploughing  and  manuring  of  the  field,  the  kind  of  manure  given, 
and  the  rotation  of  crops.  A  complete  list  of  the  weeds  found 
each  month  should  be  kept  and  compared  from  year  to  year, 
or  from  season  to  season.  After  four  or  five  years  it  would  be 
possible  to  note  whether  the  same  weeds  occurred  year  after 
year,  if  the  same  manure  was  used.  Where  the  crop  and  the 
manure  vary  from  year  to  year,  it  would  seem  likely  that  the 
constant  presence  of  certain  weeds  is  due  to  the  character  of  the 
soil.  The  presence  of  certain  weeds,  year  after  year,  in  conse- 
quence of  ploughing  operations,  would  indicate  some  relation 
between  the  life  of  the  plant  and  the  greater  depth  of  soil  through 
which  the  roots  could  penetrate ;  ploughing,  for  instance,  would 
probably  increase  the  number  of  weeds  with  a  deep-rooted  system. 
One  result  of  the  constant  ploughing  to  which  arable  land  is  natur- 
ally subjected  is,  that  many  of  the  weeds  are  annuals  ;  the  weeds 
of  meadows  and  pastures,  undisturbed  by  the  plough,  are,  as  has 
been  stated,  perennials. 

The  result  of  leaving  ground  fallow  for  a  year  and  its  effect 
on  the  next  crop  may  be  observed.  Experiments  at  Rothamsted 
on  Wheat  plots  showed  that  the  produce  of  Wheat  after  fallow  is 
considerably  higher  when  it  is  grown  continuously,  partly  owing 
to  the  fact  that  there  are  fewer  weeds. 

The  effect  of  a  wet  or  dry  season  is  best  realised  by  keeping 
a  weather  chart,  which  should  show  the  temperature  and  the 
hours  of  sunshine.  These  can  usually  be  checked  from  the  records 
of  the  meteorologist  of  the  district.  The  rainfall  and  degrees  of 


88  THE  BOOK  OF  NATURE  STUDY 

frost  should  be  also  entered.  The  date  of  cutting  the  hay,  of  the 
ripening  of  Wheat  or  Oats  should  be  recorded.  If  these  charts 
are  kept  and  compared  from  year  to  year,  the  effect  of  climatic 
changes,  which  are  perhaps  the  most  important  factor  in  the 
cultivation  of  Wheat  and  other  cereals,  can  be  estimated.  It  is 
quite  possible,  in  agricultural  districts,  to  have  charts  of  this  kind 
kept  by  even  the  lower  classes  in  a  school.  The  date  of  the  flower- 
ing of  the  different  weeds  found  in  fields  may  also  be  observed  ; 
in  this  way  children  come  to  associate  certain  plants  with  the  reap- 
ing of  Corn.  Even  those  who  live  near  a  town  can  observe  a 
great  deal  in  the  market  gardens,  so  common  in  the  neighbourhood 
of  towns. 

BIBLIOGRAPHY.— A.  D.  Hall,  Rothamsted  Experiments ;  A.  D.  Hall,  The  Soil. 


THE    SCHOOL    GARDEN 

BY  J.  E.  HENNESEY, 

Formerly  Principal  of  the  Lady  Warwick  Agricultural  School. 
Author  of  "  The  School  Garden." 

CHAPTER    V 
GENERAL 

THE  School  Garden  is  no  new  institution.  Comenius,  who  lived 
in  the  seventeenth  century,  recommended  that  every  school 
should  possess  its  own  garden,  where  the  scholars  could  learn  to 
love  trees  and  flowers  and  herbs,  and  be  taught  something  of 
their  life-stories.  A  little  later,  Francke,  who  had  an  asylum  at 
Halle  for  orphan  children,  laid  out  a  school  garden  in  which  the 
children  could  employ  their  leisure  time  with  pleasure  and  profit. 
Rousseau,  Pestalozzi,  and  Froebel  all  did  something  to  help 
forward  the  movement.  Pestalozzi,  who  had  established  on  his 
estate  at  Neuhof  a  home  for  orphans,  laid  down  the  principle  that 
the  farm  was  to  be  the  central  point  of  his  educational  work,  and 
that  his  pupils  were  to  be  instructed  at  work  and  through  work. 
While  the  idea  that  children  should  receive  instruction  by  and 
through  their  environment  was  thus  kept  alive,  it  was  not  until 
about  forty  years  ago  that  the  particular  method  of  instruction 
now  under  consideration  began  to  spread  widely.  In  the  years 
1869  and  1870  a  law  was  passed  by  the  Austrian  Government 
requiring  that  where  possible  a  garden  and  ground  for  agricultural 
demonstrations  should  be  attached  to  every  rural  school,  and 
that  wherever  natural  history  formed  a  part  of  a  school  curric- 
ulum the  instruction  should  be  based  on  material  provided  from 
a  school  garden  specially  arranged  for  the  purpose.  Since  the 
date  of  passing  of  this  law  it  is  stated  that  more  than  18,000 
school  gardens  have  been  established  in  Austria-Hungary.  Much 


90        THE  BOOK  OF  NATURE  STUDY 

valuable  help  has  been  given  by  the  Styrian  Horticultural  Society, 
which  has  annually  distributed  to  the  schools,  free  of  charge, 
large  quantities  of  seeds  and  cuttings.  Though  not  to  the  same 
extent  as  in  Austria,  the  School  Garden  has  firmly  established 
its  position  as  a  valuable  educational  instrument  in  Germany, 
France,  Belgium,  Switzerland,  Sweden,  and  Russia.  In  England, 
State  aid  is  given  to  instruction  in  School  Gardens  whether  attached 
to  elementary  schools  or  continuation  schools,  and  the  number 
of  such  gardens  has  increased  greatly  during  the  past  ten  years. 

This  general  increase  is  mainly  due  to  the  recognition  in 
present-day  educational  methods  of  the  fact  that  the  most  valuable 
and  lasting  results  are  obtained  from  teaching  gained  by  the 
pupil  through  his  own  observation  and  activity.  For  such 
teaching  the  School  Garden  offers  the  widest  scope,  because  it 
brings  the  pupil  into  direct  contact  with  a  large  variety  of  natural 
phenomena  from  the  observation  of  which  inferences  may  be 
drawn.  Moreover,  the  School  Garden  affords  an  occupation  for 
children  which  fosters  in  them  a  sense  of  the  beauty  of  nature, 
makes  them  self-reliant,  promotes  neatness,  and  tends  to  make 
them  healthier.  These  physical  and  moral  results  are  equally  as 
important  as  the  educational  ones  (using  the  word  "  educational  " 
in  its  narrower  sense).  The  economic  aspect,  again,  must  not  be 
overlooked.  Dexterity  in  the  use  of  garden  tools  and  appliances, 
exact  knowledge  of  the  "  how  "  and  "  when  "  in  planting  garden 
crops,  and  of  the  quantities  of  the  various  crops  obtainable  from 
a  garden,  are  a  valuable  possession  to  any  one,  but  more  especially 
to  those  who  live  in  a  country  district. 

In  this  country,  School  Gardens  fall  roughly  into  three  classes, 
namely,  day-school  gardens  for  boys,  day-school  gardens  for 
girls,  and  evening-school  gardens  for  adults  or  for  boys  who  have 
left  school.  Instruction  in  day-school  gardens,  whether  for  boys 
or  girls,  will  aim  at  the  general  intellectual  development  of  the 
scholars.  In  the  evening-school  gardens  the  first  place  will  be 
given  to  the  acquirement  of  such  methods  of  practical  working  as 
will  result  in  the  production  of  abundant  crops  of  good  quality. 
The  arrangement  of  the  instruction  in  the  case  of  girls  will 
naturally  take  account  of  the  facts  that  they  are  physically  not 
so  strong  as  boys,  and  that  when  they  are  grown  up  it  will  be 


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FIG.  42. — School  garden  attached  to  an  Elementary  Day  School  in  a  large  town. 
Note  the  collection  of  British  trees,  and  the  Garden  of  Refuge  which  con- 
tains a  collection  of  the  rarer  wild  plants  of  the  district. 


92  THE  BOOK  OF  NATURE  STUDY 

their  business  to  attend  to  the  flower  garden  and  window  garden 
rather  than  to  the  vegetable  garden.  At  the  same  time,  there  is 
no  reason  why  girls  should  not  be  taught  how  to  grow  strawberries, 
apples,  raspberries,  gooseberries,  currants,  and  salad  plants. 

The  instruction  should  in  all  cases  include  sketching,  drawing 
to  scale,  calculations,  elementary  science  and  composition,  but 
no  separate  time-table  for  these  sections  should  be  drawn  up, 
for  the  course  in  gardening  covers  them  all,  and  an  efficient 
teacher  may  be  trusted  to  allocate  the  proper  amount  of  time  to 
each  part  of  the  work.  The  sketching  will  deal  with  plants  and 
parts  of  plants  ;  with  operations,  such  as  grafting  ;  with  appliances 
or  with  areas,  such  as  dimensioned  sketch  plans  of  gardens  and 
beds.  Drawing  to  scale  will  be  for  the  most  part  confined  to  the 
plans  of  gardens  and  beds,  or  to  sectional  drawings  of  a  tool- 
house,  hot-bed,  frame,  and  so  forth.  Calculations  will  cover 
areas  of  beds  (whether  circular,  rectangular,  or  triangular) ; 
weights  and  volume  of  seed  and  produce  ;  weights  of  artificial 
manures  and  farmyard  manure  employed  ;  cost  of  seed,  labour, 
rent,  and  appliances  ;  value  of  produce  ;  average  yields  ;  percen- 
tages. It  is  highly  important,  more  especially  in  the  case  of 
country  lads,  that  full  attention  should  be  given  to  the  quantitative 
side  of  the  work.  It  is  very  desirable  that  some  instruction  should 
be  given  in  the  chemistry  of  air,  water,  and  carbon,  otherwise 
it  is  not  possible  for  the  pupils  to  understand  how  a  plant  feeds 
and  breathes.  In  addition,  some  attention  should  be  given  to 
evaporation,  solution,  filtration,  specific  heat  and  the  thermometer, 
atmospheric  pressure  and  the  barometer.  The  soil  of  the  garden 
should  be  air  dried,  and  its  texture  approximately  determined.  The 
whole  of  this  work  in  elementary  physics  and  chemistry  can  be 
carried  out  with  quite  inexpensive  apparatus.  If  there  is  insufficient 
apparatus  to  provide  a  set  for  each  boy,  the  class  should  be  formed 
into  groups,  and  each  group  should  perform  the  experiments. 
The  pupils  should  themselves  perform  each  little  investigation. 
What  a  boy  finds  out  for  himself  becomes  a  part  of  his  mental 
equipment ;  experiments  which  he  sees  the  teacher  perform  make 
but  a  comparatively  feeble  impression  on  his  mind,  while  mere 
lecturing  by  the  teacher  is  frequently  not  only  a  waste  of  time 
but  may  be  positively  harmful. 


SCHOOL  GARDENS  93 

The  associated  course  of  work  thus  briefly  outlined  is  intended 
for  pupils  beginning  work  in  the  School  Garden  at  about  the  age 
of  twelve.  It  will  extend  over  two  years,  and  elementary  science 
will  be  taken  in  the  second  year.  So  far  as  children  under  twelve 
are  concerned,  the  associated  work  need  not  extend  beyond 
sketching,  brushwork,  nature  knowledge  based  on  the  objects 
of  the  garden,  and  simple  composition. 

It  may  be  useful  at  this  point  to  give  an  example  of  the 
method  for  combining  sketching,  drawing  to  scale,  and  calcula- 
tions with  the  garden  work.  Suppose  the  object  about  which 
the  instruction  is  to  be  grouped  is  a  hot-bed.  Having  made 
the  hot-bed  and  placed  the  frame  in  position,  each  boy  should 
make  a  sketch  of  the  whole,  showing  all  the  essential  features. 
With  a  measuring  stick,  notched  so  as  to  measure  to  a  quarter 
foot,  he  will  then  take  all  the  dimensions,  that  is  to  say,  the 
length,  breadth,  and  depth,  at  front  and  back  of  the  frame.  These 
dimensions  as  they  are  taken  off  will  be  entered  on  the  sketch. 
The  boys  will  then  go  into  the  classroom  and  draw  a  plan  and 
elevation  of  the  whole.  In  this  particular  case  not  many  calcula- 
tions of  practical  value  can  be  based  on  the  work,  but  the  boys 
might  be  asked  to  determine  (a)  the  area  of  the  base  of  the  manure 
heap,  (6)  the  area  of  the  base  of  the  frame,  (c)  the  number  of  cubic 
feet  of  air  contained  inside  the  frame. 

For  day-school  gardens  it  is  desirable  for  a  number  of  reasons 
that  the  teacher  should  be  a  member  of  the  ordinary  school  staff, 
for  he  will  maintain  better  discipline,  he  will  be  in  touch  more 
nearly  with  the  pupils,  and  he  will  more  efficiently  carry  out  the 
associated  instruction  than  would  a  visiting  teacher.  Besides, 
it  is  an  excellent  thing,  more  especially  in  a  rural  school,  for 
one  member  of  the  staff  at  least  to  be  thus  brought  into  close 
contact  with  one  aspect  of  rural  life  and  work. 

SECTIONS  OF  THE  SCHOOL  GARDEN 

The  best  methods  of  growing  all  the  common  vegetables 
must  of  necessity  be  the  first  consideration,  because  physical 
well-being  is  a  preliminary  to  all  work  and  thought.  A  nursery 
for  young  plants  must  also  be  provided.  The  great  increase  in 


94 


THE  BOOK  OF  NATURE  STUDY 


recent  years  in  fruit  consumption  in  this  country,  the  profitable- 
ness of  fruit  growing,  and  the  large  importations  of  fruit  from 
the  Colonies  and  the  United  States,  all  point  to  the  advisability 
of  establishing  a  fruit  plot.  In  rural  schools  it  is  an  excellent 
plan  to  set  aside  one  portion  of  the  garden  for  specimens  of 
agricultural  plants,  manurial  demonstration  plots,  and  for  a  set 
of  plots  illustrating  a  rotation  of  agricultural  crops.  All  persons 
who  have  had  experience  of  rural  education  will  recognise  the 
importance  of  giving  boys  adequate  practice  in  the  identification 
of  species  and  varieties  of  agricultural  plants  and  seeds.  So  far 


FIG.  43. — Arrangement  of  a  school  garden  suitable  for  boys  of  eleven  to 
fourteen  years  of  age.     Individual  plots. 

as  the  specimen  plots  are  concerned,  it  will  be  sufficient  if  just 
a  clump  of  each  be  sewn,  the  area  covered  by  each  specimen 
being  about  one  square  foot,  with  a  space  of  six  inches  between 
each  clump.1 

It  may  be  here  mentioned  that  in  German  school  gardens  a 
small  collection  of  injurious  arid  poisonous  plants  is  regarded  as 
an  important  feature,  while  in  a  few  school  gardens  in  this  country 
the  teachers  have  succeeded  in  establishing  a  complete  collection 
of  British  trees.  Last  but  not  least,  flowers  should  be  grown, 
and  a  special  border  set  apart  for  that  purpose.  A  collection 

1  A  better  way,  perhaps,  especially  for  clovers  and  grasses  is  to  sow  in  drills,  each  drill 
being  about  three  feet  in  length. 


SCHOOL  GARDENS  95 

of  perennials  can  be  gradually  acquired,  by  gift  as  often  by  pur- 
chase, and  such  a  collection  will  be  a  constant  source  of  interest 
to  the  teaching  staff  and  to  visitors,  as  well  as  to  the  scholars. 
It  may  perhaps  be  said  that  to  suggest  the  provision  of  school 
gardens  containing  the  six  sections  specified  above  is  a  counsel 
of  perfection.  This  may  be  a  sound  contention  so  far  as  town 
gardens  are  concerned,  because  of  the  high  price  of  urban  land 
and  the  frequently  inconvenient  distribution  of  the  small  quantity 
available.  In  country  places,  however,  provided  that  the  school 
staff  and  the  local  managers  are  in  earnest,  there  should  be  no  diffi- 
culty in  hiring  the  half  acre  or  so  of  ground  necessary  for  obtaining 
the  fullest  possible  value  from  a  well  planned  course  of  work. 
The  garden  should  be  a  place  in  which  not  only  the  boys  and 
girls,  but  also  their  teachers,  parents,  and  friends,  can  find 
pleasure,  interest,  and  profit. 


CHAPTER    VI 

SELECTION  OF  SITE  AND  PRELIMINARY  OPERATIONS 

FOR  convenience  in  carrying  out  the  practical  work  and  the 
associated  indoor  work  it  is  important  that  the  garden  should  be 
near  the  school  building,  and,  provided  that  it  can  be  securely 
fenced  in,  it  is  desirable  that  it  should  be  open  to  the  view  of 
those  passing  by  in  the  road  :  the  interest  and  sympathy  of  people 


FIG.  44  — Diagram  showing  how  the  direction  of  slope  of  the  surface  of  the  soil  affects 
the  quantity  of  heat  and  light  received  from  the  sun. 

living  in  the  neighbourhood  is  thus  stimulated.  The  garden 
must  also  be  near  a  satisfactory  water  supply,  as  the  necessity 
for  fetching  water  from  a  distance  takes  up  valuable  time  and 
tends  to  disorganise  the  work.  The  best  soil  available  should  be 
secured,  as,  although  there  are  some  advantages  in  watching  the 
gradual  amelioration  of  a  piece  of  unfertile  ground,  these  advan- 
tages are  more  than  counterbalanced  by  the  discouraging  slowness 
of  the  process  in  the  case  of  very  light  or  very  heavy  soils.  The 
garden  ground  should  be  either  horizontal  or  should  have  a  gentle 
slope  south-east,  south-west,  or  west.  A  slope  towards  the  north, 


ROYAL  HORTICULTURAL  SOCIETY'S  GARDENS,  WiSLEY 
The  Rose  Pergola:    Students  at  Work 


ROYAL  HORTICULTURAL  SOCIETY'S  GARDENS,  WISLEY 
A  Class  in  the  Laboratory 


SELECTION  OF  SITE 


97 


is  a  great  disadvantage.  The  reason  for  this  will  be  obvious  from 
a  consideration  of  the  accompanying  sketch  (Fig.  44). 

It  will  be  seen  that  if  SPN  represents  a  piece  of  ground  one 
half  of  which  slopes  from  the  ridge  P  in  the  southerly  direction 
PS,  and  the  other  half  slopes  in  the  northerly  direction  PN, 
while  the  area  of  the  ground  on  the  two  slopes  is  the  same,  the 
total  amount  of  sunlight  and  heat  which  falls  on  the  ground  and 
is  represented  by  RNSQ,  is  not  equally  divided  between  the 
two  slopes — more  than  half  (represented  by  OPSQ)  falling  on 
the  southern  slope,  and  a  correspondingly  diminished  quantity 
(represented  by  OPNR)  falling  on 
the  northern  half.  The  angle  of 
incidence  of  the  sun's  rays  is  in- 
creased where  the  ground  has  a 
southern  slope,  and  this  is  in  fact 
equivalent  to  a  change  in  latitude. 
If  the  garden  ground  is  horizontal 
it  must  not  be  in  an  exposed  situa- 
tion, for  it  is  impossible  to  obtain 
satisfactory  results  when  plants  are 
open  to  cold  sweeping  winds  from 
the  north  or  east.  If  such  a  situa- 
tion is  unavoidable,  steps  should 
be  taken  at  the  outset  to  provide 
shelter  in  those  directions  either 
by  planting  a  thickset  hedge  of 

quickly  growing  plants  or  by  making  a  plantation  of  trees  to  form 
a  wind-break.  For  the  purpose  of  increasing  the  educational  value 
of  the  garden  the  latter  is  the  better  plan,  because  a  variety  of  trees 
may  be  employed  which  will  afford  useful  material  for  nature-study 
lessons.  A  very  good  arrangement  would  be  to  plant  one  row  of 
British  trees  on  the  outside,  and  on  the  inner  side  of  these,  alter- 
nating with  them,  a  row  of  plum  trees,  which  are,  for  the  most 
part,  very  hardy  and  cold  resisting.  While  on  the  subject  of  trees, 
it  may  be  useful  to  point  out  that  large  trees  like  the  oak,  elm,  ash, 
and  beech  cover  a  very  considerable  area  both  above  and  below 
ground ;  their  dense  foliage  intercepts  a  great  deal  of  the  rainfall 
which  evaporates  from  the  surfaces  of  the  leaves  instead  of 

VOL.  V.  —  7 


FIG.  45. — An  Error  in  Planting.  Show- 
ing the  mistake,  or  result  of  planting 
too  near  to  large  trees  or  shrubs,  as 
the  roots  of  the  latter  rob  the  plants 
of  food.  A,  herbaceous  plants ;  B, 
tree  roots. 


98  THE  BOOK  OF  NATURE  STUDY 

reaching  the  ground,  while  their  roots,  which  extend  sometimes 
to  a  distance  horizontally  of  twenty  or  thirty  feet,  abstract 
large  quantities  of  water  and  plant  food  from  the  area  embraced 
by  them.  The  garden  should  therefore  be  so  situated  that  it  is 
not  nearer  than  the  distance  mentioned  to  forest  trees  of  con- 
siderable size. 

The  best  soil  for  a  garden  is  a  medium  loam,  that  is  to  say, 
a  soil  containing  about  50  per  cent,  of  soil  particles  intermediate 
in  size  between  the  large  grains  (sand)  and  the  very  fine  ones 
(clay),  which  possess  a  diameter  of  only  from  one-hundredth 
to  one-thousandth  of  a  millimetre.  A  sandy  soil  is  characterised 
by  its  warmth,  porosity,  feeble  power  of  holding  capillary  water, 
inability  to  "  bind/'  and  deficiency  of  mineral  salts.  While, 
therefore,  on  the  one  hand  it  is  easy  to  work  and  produces  early 
crops,  it  tends  on  the  other  hand  to  become  parched,  and  soluble 
plant  food  is  readily  washed  through  it  into  the  subsoil.  A 
clay  soil  is  cold,  tenacious,  and  heavy  in  working  ;  water  passes 
through  it  only  very  slowly.  Owing  to  the  fineness  of  its  con- 
stituent particles  it  is  always  moist,  at  any  rate  just  below  the 
surface.  It  absorbs  and  retains  certain  mineral  matter  from 
aqueous  solutions.  Roughly  speaking,  very  light  soils  are  satis- 
factory only  in  moist  seasons,  and  very  heavy  soils  only  in  fairly 
dry  ones.  To  improve  the  water-holding  capacity  of  a  light  soil, 
plenty  of  decayed  vegetable  matter  should  be  worked  into  it, 
and  the  same  substance  only  slightly  decayed  will,  if  worked  into 
a  heavy  soil,  tend  to  provide  air  spaces  and  thus  make  it  more 
porous.  Heavy  soils  are  also  as  a  rule  improved  by  liming. 

The  same  considerations  as  those  mentioned  apply  to  the 
underlying  rock.  Soils  situated  on  sand,  gravel,  or  chalk  are 
warm  and  well  drained,  those  resting  on  clay  are  cold  and  apt 
to  become  waterlogged.  Hence  where  the  underlying  soil  is 
composed  of  clay  the  garden  must  be  drained.  The  main  drain, 
at  a  depth  of  three  and  a  half  feet,  should  run  down  the  centre 
of  the  garden  and  into  a  water  course  ;  the  subsidiary  drains 
should  be  at  a  depth  of  three  feet.  The  accompanying  sketch 
(Fig.  46)  shows  the  arrangement.  If  the  expense  is  considered 
too  great  a  main  drain  at  a  depth  of  two  and  a  half  feet,  with 
subsidiary  drains  at  a  depth  of  two  feet  may  be  laid,  but  this 


PRELIMINARY  OPERATIONS 


99 


means  bringing  the  drain  pipes  perilously  near  the  spade  when 
trenching  operations  are  in  progress,  and  should  only  be  adopted 
when  the  soil  is  exceptionally  heavy. 

\Yhether  a  main  drainage  system  is  installed  or  not,  it  is 
essential  on  almost  any  soil  except  the  very  lightest  that  provi- 


FIG.  46. — Drainage  system  for  a  stiff  soiL 

sion  should  be  made  for  carrying  off  the  surface  water.  As  the 
cultivated  ground  will,  in  a  year  or  two,  be  at  a  higher  level  than 
the  paths,  the  surplus  surface  water  will  tend  to  run  into  the 
paths,  and  the  surface  drains  are  therefore  most  conveniently 
laid  in  the  paths.  These  surface  drains  are  very  simply  made, 
and  there  is  no  reason  why  the  boys  should  not  themselves 


loo  THE  BOOK  OF  NATURE  STUDY 

construct  them.  After  the  paths  have  been  taken  out,  and 
before  they  are  gravelled,  a  trench  should  be  taken  out  in  the 
middle  of  each  path,  eight  inches  wide  and  six  inches  deep.  The 
trench  is  then  filled  in  with  good  sized  pieces  of  broken  brick 
and  flints.  When  covered  in  with  gravel  the  interstices  between 
the  bricks  or  flints  will  provide  a  passage  for  water.  The  trenches 
must,  of  course,  have  a  slight  slope,  and  the  main  trend  will  run 
to  a  watercourse  of  some  kind.  The  sketch  (Fig.  47)  shows  a 
section  of  a  path  thus  constructed. 

Assuming  that  a  piece  of  agricultural  land  is  taken  for  the 
school  garden,  the  ground  must,  after  having  been  drained  (if 
necessary),  be  trenched.  In  the  case  of  an  evening-school  garden 
this  work  ought  to  be  done  by  the  pupils.  It  is,  however,  too 
heavy  work  for  young  boys,  and  must  therefore,  in  the  case  of 


SURFACE  Of  GARDEN 

SURFACE  OF  PATH 


* 

FIG.  47. — Section  of  garden  path  showing  how  it  should  be  drained  and  gravelled. 

day-school  gardens,  be  carried  out  beforehand  by  men.  It  is 
not  desirable,  except  in  the  case  of  an  old-established  garden 
possessing  a  deep  soil,  to  bring  the  subsoil  to  the  surface.  Hence, 
where  agricultural  land  has  been  taken,  the  following  method 
of  trenching  it  should  be  adopted.  The  ground  is  marked  out 
by  means  of  the  measuring  stick  into  rectangles  a  yard  wide, 
and  running  the  whole  length  of  the  garden,  as  in  the  annexed 
figure  (Fig.  48). 

The  whole  of  the  soil  in  the  rectangles  AD  and  CF  is  taken 
out  to  one  spade's  depth,  and  wheeled  to  the  other  end  beyond 
JK.  Similarly,  a  second  spade's  depth  of  soil  is  taken  out  of 
rectangle  AD  and  wheeled  to  the  other  end.  As  this  is  not  to 
be  brought  to  the  surface  of  the  soil,  it  must  be  kept  separate 
from  the  soil  of  the  top  spit  already  removed.  The  bottom  of 
the  trench  AD  is  then  dug  over,  and  this  rectangle  has  thus  been 
dug  to  a  depth  of  three  spades.  Next,  the  second  spade's  depth 


PRELIMINARY  OPERATIONS' :  '*' ' 


101 


of  soil  is  transferred  from  the  rectangle  CF  to  the  rectangle  AD, 
and  finally  the  top  spit  of  the  rectangle  EH  is  used  to  fill  up  the 
rectangle  AD.  This  series  of  operations  is  then  repeated  in  the 
rectangles  CF  and  EH,  and  so  on  in  successive  rectangles  until 
JK  is  reached,  when  there  will  be  two  rectangles  at  that  end, — 
one  deficient  of  soil  to  the  extent  of  one  spade's  depth  and  the 


FIG.  48. — Arrangement  of  ground  for  full  trenching. 

other  deficient  to  the  extent  of  two  spades'  depth.     These  will 
be  filled  with  the  soil  first  removed  from  the  other  end. 

Although  boys  will  not,  as  a  rule,  carry  out  this  operation 
of  full  trenching  when  the  garden  is  being  formed,  they  should, 
if  possible,  see  it  done,  and  should  make  a  sketch  and  write  a 
description  of  it.  Later,  when  the  garden  is  well  established, 
every  boy  should,  once  in  his  course,  take  part  in  the  operation. 
The  preliminary  trenching  having  been  completed,  we  now  have 
to  consider  fencing  and  path-making.  This  work  is  not  beyond 


102  THE  BOOK  OF  NATURE  STUDY 

the  strength  of  boys  of  twelve  to  fourteen.  For  fencing  there 
is  no  better  plant  than  the  Whitethorn.  This  can  be  bought  in 
quantities  very  cheaply.  The  plants  should  be  set  into  the 
ground  in  a  double  row,  the  rows  being  six  inches  and  the  plants 
at  half  that  distance  apart.  The  planting  should  be  done  at 
the  end  of  October.  Of  other  plants  used  for  fencing,  mention 
may  be  made  of  Privet,  which,  however,  does  not  make  a  suffi- 
ciently strong  fence ;  and  Beech,  which  while  making  a  strong  and 
handsome  fence,  is  slow  in  growth,  especially  on  soils  other  than 
sand  or  chalk.  For  very  light  soils  the  quickest  growing  plant 
is  perhaps  the  Laurel.  If  cuttings  (hedge  trimmings  will  do) 
of  Laurel  are  inserted  in  a  small  trench  in  October  to  a  depth  of 
about  four  inches  they  will  readily  root,  and  form  a  fairly  satis- 
factory fence  in  two  or  three  years  time. 

The  number  of  paths  required  will  depend  on  the  size  of  the 
garden  and  the  variety  of  its  arrangement.  In  a  garden  of  a 
considerable  size  there  should  be  one  main  path  three  feet  in 
width,  with  subsidiary  paths  two  feet  in  width.  Where,  in  addi- 
tion to  vegetable  portions,  there  are  flower  borders,  agricultural 
specimen  plants,  agricultural  demonstration  plots,  and  a  fruit 
plot,  there  should  be  paths  running  alongside  each  of  them. 
The  paths  should  be  made  by  the  boys.  For  this  purpose  the 
outlines  of  the  paths  are  marked  out  with  stakes,  and  the  soil  is 
then  taken  out  to  a  depth  of  three  inches.  This  soil  may  either 
be  scattered  over  the  rest  of  the  garden  or  used,  as  a  bottom 
for  compost  or  manure  heaps.  Next  the  surface  drains  are  made 
as  described  on  page  100  ;  and  lastly,  the  material  for  the  paths 
is  filled  in  and  well  trodden  or  rolled  down.  This  material  may 
be  either  gravel  or  preferably  cinders  or  "  brise  "  from  the  gas 
works,  mixed  with  a  little  slaked  lime  to  cement  the  whole.  Well 
made  paths  add  greatly  to  comfort  in  getting  about  the  garden. 
It  may  be  desirable  to  provide  an  edging  to  the  main  path.  This 
is  sometimes  made  with  ornamental  tiles,  or  with  bricks  stuck 
endwise  into  the  ground  ;  or  box  may  be  planted,  but  this  is 
objectionable,  because  it  affords  a  hiding-place  for  slugs.  Probably 
the  best  edging  is  one  made  of  boards  seven  inches  wide  by  three- 
quarters  of  an  inch  in  thickness.  These,  after  being  tarred,  are 
let  into  the  ground  to  a  depth  of  three  inches  and  secured  in 


EQUIPMENT  103 

position  by  being  nailed  to  short  posts,  two  inches  square  and 
eighteen  inches  long,  driven  into  the  ground  until  flush  with  the 
upper  edge  of  the  planks.  The  cost  of  this  edging  is  about  sixpence 
per  yard,  or  say,  one  pound  for  a  single  main  path.  It  will  save 
a  great  deal  of  trouble  in  keeping  the  path  clean  and  the  garden 
neat. 

The  equipment  required  for  a  school  garden  will  vary  with 
the  age  of  the  pupils,  and  with  the  variety  of  the  work  done  in  it. 
In  elementary  school  gardens  each  boy  should  have  a  set  of 
tools,  consisting  of  a  spade,  fork,  rake,  Dutch  hoe  and  trowel. 
Each  tool  of  each  set  should  have  a  number  burnt  or  cut  on  it 
for  purposes  of  identification.  The  cost  of  each  set  will  be  about 
twelve  shillings.  In  addition,  for  general  use  there  should  be 
provided  two  or  three  draw  hoes,  a  barrow,  two  watering  cans, 
three  garden  lines,  a  thermometer,  wooden  labels,  flower-pots, 
and  bast,  costing  altogether  about  two  pounds.  If  possible  a 
spraying  machine  costing  thirty  shillings,  and  a  budding  knife, 
should  also  be  provided.  Some  kind  of  storehouse  must  be 
provided  for  the  tools  and  materials  used  in  the  garden,  and  for 
this  purpose  a  wooden  shed,  ten  feet  long,  five  feet  wide,  and  six 
feet  to  the  eaves,  is  sufficient.  A  portable  shed  of  this  size  can 
be  bought  for  about  two  pounds.  For  more  advanced  work, 
however,  it  is  a  great  convenience  if  a  larger  shed,  to  be  used  as 
a  potting  and  store  shed  as  well  as  a  toolhouse,  can  be  provided. 
A  shed  measuring  sixteen  feet  by  ten  feet,  and  provided  on  one 
side  with  a  bench  two  feet  wide,  and  a  shelf  six  inches  wide, 
will  cost  about  five  pounds.  If,  as  is  strongly  recommended, 
a  hot-bed  is  used  for  raising  seedlings  and  striking  cuttings,  a 
frame  with  one  or  two  lights  will  be  required,  and  this  will  cost 
from  one  to  two  pounds,  according  to  size. 

Besides  the  equipment  above  mentioned,  certain  materials 
will  be  required  for  carrying  out  a  good  course  of  work  in 
gardening.  Chief  of  these  are  manure  (farmyard  and  artificial), 
sand,  leaf-mould,  leaves,  and  loam.  The  best  farmyard  manure 
is  that  of  the  horse.  This  should,  if  possible,  be  obtained  in  the 
green  (that  is  unfermented)  state,  when  it  consists  of  unde- 
composed  straw  saturated  with  urine  from  the  animals  and 
mixed  with  their  dung.  In  this  state  it  can  be  used  for  making 


104 


THE  BOOK  OF  NATURE  STUDY 


a  hot-bed,  and  afterwards,  when  spent,  can  be  spread  over  the 
beds.  The  cost  of  farmyard  manure  is  from  two  shillings  and 
sixpence  to  five  shillings  per  tumbril  load,  weighing  about  one 
ton.  Of  artificial  manures  the  only  ones  required  are  :  (a)  super- 
phosphate of  lime  and  steamed  bone  flour,  which  should  as  a 
rule  be  applied  together,  because  the  bone  flour  helps  to  dilute 
the  acidity  of  the  superphosphate  ;  (6)  nitrate  of  soda  ;  (c)  sulphate 
of  potash ;  (rf)  sulphate  of  ammonia.  Clean  white  sand  will  be 
required  for  making  up  potting  mixtures,  and  also  for  bulb 
planting.  Leaf  mould  can  be  obtained  from  the  surface  of  the 
ground  under  trees.  Dead  leaves,  which  are  required  for  the 
hot-bed,  can  always  be  gathered  from  the  roadside  in  November. 
Another  ingredient  of  the  potting  mixture,  termed  by  the 
gardener  "  yellow  loam,"  is  obtained  by  cutting  sods  from  the 
surface  of  an  old  pasture  or  from  the  grassy  edges  of  the  road 
and  piling  these  in  a  heap  where  the  grass  is  left  to  decay  for 
three  or  four  months. 


ALLOCATION   OF   THE   GROUND   TO   THE   STUDENTS 

As  has  already  been  stated,  it  is  generally  desirable  in  the 
case  of  girls  that  their  work  should  be  confined  to  the  cultivation 
of  flowers,  salad  plants,  herbs,  and 
fruit.  For  outdoor  flowers  various 
corners  of  the  garden  or  playground 


FIG.  49.— Preparing  Ground  for  Borders.  A,  soil  FIG.  50.  —  Herbaceous  Borders.  A, 
well  broken  up  ;  B,  soil  generously  manured  ;  path  ;  B,  B,  borders  ;  C,  C,  boundary 
C,  loosened  sub-soil.  of  borders. 

may  be  assigned  to  individual  pupils,  but  if  the  girls'  class  is  a  fairly 
large  one  an  herbaceous  border  should  be  formed,  four  or  five  feet 


ALLOCATION  OF  GROUND 


105 


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PERENNIALS    ANNUALS    BULBS  AND  ROSETREES 

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ECONOMI 

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FIG.  51. — An  industrial  garden  suitable  for  evening  schools,  cultivated  co-operatively. 


106  THE  BOOK  OF  NATURE  STUDY 

in  width,  and  long  enough  to  provide  a  length  of  not  less  than 
eight  or  ten  feet  for  each  worker.  The  whole  border  will  be 
arranged  beforehand  on  a  harmonious  plan  which  takes  account  of 
the  sizes  of  the  mature  plants  and  the  colours  of  their  flowers,  but, 
subject  to  this,  each  girl  will  work  independently  of  the  rest 
of  the  class.  In  addition  to  this  outdoor  cultivation,  all  girls 
ought  to  be  taught  the  management  of  the  commoner  indoor 
plants  and  window  plants.  Further,  every  school  garden, 
whether  for  the  instruction  of  boys  or  of  girls,  should  provide 
for  flowers  being  grown.  Quite  young  children,  from  the  age  of 
eight  up  to  twelve,  may  have  little  plots  assigned  to  them  in 
which  they  can  grow  and  tend  bulb  plants  and  hardy  annuals. 
In  the  case  of  boys  aged  from  twelve  to  sixteen  it  has  been  usual 
to  assign  a  plot  to  each  boy,  or  to  a  senior  and  junior  boy.  The 
advantage  of  this  individual-plot  system  is  that  a  spirit  of 
emulation  is  roused,  and  boys  are  ready  to  work  on  their  plots 
out  of  school  hours  when  this  is  necessary.  It  is  easier,  moreover, 
for  the  teacher  to  detect  the  shortcomings  and  mistakes  of 
individual  workers.  On  such  a  system  each  boy  should  have 
not  less  than  one  rod,  and  preferably  one  and  a  half  to  two  rods, 
to  cultivate.  The  minimum  of  area  assigned  to  each  boy  at  this 
age  should  be  three-quarters  of  a  rod.  Where  a  junior  and  a 
senior  boy  cultivate  a  plot  jointly  the  minimum  area  should  be 
one  and  a  half  rods.  The  individual  plot  system  has,  however, 
two  drawbacks.  In  the  first  place,  the  English  character  is  averse 
to  co-operative  work,  although  it  is  generally  recognised  that 
one  of  the  most  important  qualities  to  be  fostered  in  members 
of  a  rural  community  is  the  spirit  of  mutual  self-help.  If  this 
spirit  is  to  be  encouraged  it  is  urged,  by  some  persons  of  experi- 
ence in  rural  education,  that  a  beginning  should  be  made  during 
school  life.  Further,  the  school  garden  should,  inter  alia,  be  a 
model  of  what  a  private  garden  should  be.  The  vegetable  beds 
should  be  arranged  so  as  to  provide  a  satisfactory  rotation  of 
crops.  Corners  should  be  occupied  by  flowering  shrubs,  unsightly 
spaces  should  be  screened  by  trees  or  bushes,  and  the  garden  as 
a  whole  should  be  pleasing  to  the  eye. 

Now,  it  is  difficult,  if  not  impossible,  to  form  a  school  garden 
arranged  on  the  plot  system  which  shall  comply  with  this  con- 


ALLOCATION  OF  GROUND  107 

dition  of  being  a  model  garden,  and  in  too  many  instances  the 
school  garden  is  a  spot  devoid  of  interest  and  even  positively 
ugly.  Little  rectangular  beds  of  cabbages,  onions,  beet,  potatoes, 
and  so  on,  in  monotonous  succession,  bounded  by  bare  palings 
and  walls,  make  a  picture  the  reverse  of  educational.  The  weight 
of  expert  opinion  seems  to  be  on  the  side  of  individual  work,  so 
far  as  da}^school  gardens  are  concerned,  but  as  a  compromise  the 
possibility  is  suggested  of  laying  out  the  garden  in  single  large 
beds,  there  being  one  bed  of  each  crop,  but  assigning  particular 
rows  to  particular  boys.  In  this  way,  while  the  garden  would 
present  the  appearance  of  an  ordinary  garden,  each  boy  would 
still  have  his  own  sets  of  plants,  for  the  management  of  which 
he  would  be  entirely  responsible. 

If  the  co-operative  method  is  not  adopted  in  the  case  of  day- 
school  gardens,  it  is  highly  desirable  that  evening-school  gardens 
should  be  cultivated  in  common.  The  teaching  here  will  lean 
more  to  the  utilitarian  and  commercial  side.  Grading,  packing, 
and  marketing-*  of  produce  might  be  taught,  and  this  can  only 
be  done  satisfactorily  when  the  garden  is  cultivated  in  common. 
The  industrial-school  garden  affords  a  valuable  instrument  for 
the  instruction  of  the  younger  members  of  the  rural  population 
in  the  essentials  of  co-operation,  and  should  be  a  fitting  intro- 
duction to  the  more  complex  co-operative  methods  which  are 
generally  recognised  as  necessary  to  ensure  success  in  the  manage- 
ment of  small  holdings. 

Figs.  42,  43,  and  51  show  the  arrangement  of  the  beds 
adopted  in  three  distinct  types  of  schools. 


CHAPTER  VII 
TILLAGE  OPERATIONS  AND  MANURING 

IN  order  that  seeds  may  germinate  the  seed  bed  must  supply  to 
them  warmth,  moisture,  and  oxygen.  Subject  to  this  supply 
the  seedling  plant  requires  nothing  else  until  it  has  exhausted 
the  store  of  food  material  contained  in  the  seed.  When  that 
point  is  reached  the  plant  begins  to  draw  upon  the  soil  for  mineral 
substances,  in  a  soluble  condition,  containing  nitrogen,  phosphorus, 
sulphur,  potassium,  iron,  magnesium,  and  calcium.  Of  these 
seven  elementary  substances,  four,  namely,  sulphur,  iron, 
magnesium,  and  calcium,  are  nearly  always  present  in  the  soil  in 
sufficient  quantity,  although  not  necessarily  in  a  soluble  condition. 
On  the  other  hand,  nitrogenous,  phosphatic,  and  potassic  com- 
pounds tend  to  become  deficient  in  the  soil,  and  must  therefore 
be  supplied  either  by  means  of  farmyard  manure  or  by  such 
artificial  manures  as  nitrate  of  soda,  sulphate  of  ammonia 
(nitrogenous),  superphosphate  of  lime,  steamed  bone  flour,  basic 
slag  (phosphatic),  sulphate  of  potash,  and  kainit  (potassic). 
Nitrogenous  manures  appear  to  encourage  vegetative  growth 
and  the  production  of  foliage.  The  chief  nitrogenous  artificial 
manure  is  nitrate  of  soda,  and  as  this  substance  is  readily  soluble 
in  water  it  should  be  applied  to  the  soil  in  spring,  when  it  will 
be  absorbed  quickly  by  the  roots  of  the  growing  plants,  and  there 
will  not  be  the  same  risk  of  loss.  Experience  shows  that  about 
three  pounds  per  rod  may  be  applied  with  advantage  in  most 
cases.  Basic  slag  and  steamed  bone  flour  become  soluble  only 
slowly,  and  may  therefore  be  applied  in  the  autumn  at  the  rate 
of  four  pounds  per  rod.  Sulphate  of  potash  is  the  most  suitable 
potassic  manure  for  the  garden.  Like  nitrate  of  soda,  it  is  soluble 
in  water,  and  should  therefore  be  applied  in  the  spring,  at  the 
rate  of  two  pounds  per  rod.  It  frequently  gives  good  results 
with  potatoes  and  strawberries.  Whether  the  garden  soil  would 


TC8 


TILLAGE  OPERATIONS  AND  MANURING          109 

be  benefited  by  the  application  of  these  artificial  manures  is  a 
question  which  should  be  determined  by  experiment,  and  for 
this  purpose  one  or  two  rows  of  each  crop  should  be  separately 
treated. 

Lime,  in  the  form  of  marl,  ground  limestone,  or  freshly  slaked 
lime,  may  generally  be  applied  with  advantage  at  intervals  of 
about  four  years.  Lime  tends  to  be  washed  by  rain  from  the 
upper  soil  into  the  subsoil.  In  soil  which  has  been  heavily 
manured  with  farmyard  manure  or  decayed  vegetation  for 
some  years  there  is  generally  an  accumulation  of  organic  acids, 
especially  humic  acid,  which  may  seriously  affect  the  healthy 
action  of  the  roots  and  arrest  the  work  of  the  soil  bacteria.  In 
such  a  case  the  application  of  lime  will  neutralise  the  free  acid 
of  the  soil  and  render  the  soil  sweet. 

Of  almost  greater  importance  than  the  chemical  character 
of  the  soil  is  its  physical  condition,  and  this  is  capable  of  almost 
indefinite  improvement  by  tillage  properly  carried  out  at  the 
proper  time,  and  by  the  application  of  decaying  vegetable  matter 
and  lime.  Digging,  hoeing,  raking,  and  pressing  are  the  four 
chief  methods  employed  in  gardening  for  the  improvement  of 
the  physical  condition  of  the  soil,  and  these  will  now  be  con- 
sidered in  some  detail. 

The  object  of  digging  is  to  provide  a  moderately  firm  soil 
in  which  the  roots  of  the  plants  can  spread  freely,  and  to  admit 
air,  moisture,  and  carbonic  acid,  which  act  chemically  upon 
the  insoluble  reserve  mineral  matter  of  the  soil,  rendering  it 
available  for  absorption  by  the  roots.  Boys  should  be  instructed 
how  to  hold  the  spade  properly,  how  to  use  their  strength  to 
the  best  advantage  in  driving  the  spade  into  the  ground  and  in 
lifting  the  soil,  and  how  to  place  the  soil  so  as  to  have  a  fairly 
level  surface.  The  method  of  full  trenching  has  been  already 
described.  Bastard  trenching,  or  double  digging,  consists  of 
cultivating  the  soil  to  a  depth  equal  to  that  of  twice  the  spade's 
depth.  As  in  full  trenching,  the  ground  to  be  double  dug  is 
marked  off  into  rectangles  one  yard  wide  (see  Fig.  52). 

The  whole  of  the  top  spit  in  the  rectangle  ACDB  is  dug  out, 
placed  in  a  wheelbarrow,  and  transferred  to  the  other  end  of 
the  plot  beyond  GH.  The  second  spit  of  ACDB  is  then  dug 


no 


THE  BOOK  OF  NATURE  STUDY 


K 


over.  Next,  the  top  spit  of  the  rectangle  CEFD,  is  dug  out  and 
transferred  to  rectangle  ACDB,  the  second  spit  of  CEFD  is  then 
dug  over.  This  series  of  operations  is  repeated  on  successive 
rectangles  until  GH  is  reached,  when  the  top  spit  of  ACDE  is 
used  to  fill  up  the  rectangle  GHLK.  The  effect  of  the  operation 
thus  is  that  the  soil  has  been  thoroughly  stirred  to  two  spades' 
depth,  but  no  subsoil  has  been  brought  to  the  surface.  The 
reason  for  not  bringing  the  subsoil  to  the  surface  is  that  it  is 
frequently  incompletely  aerated,  and  not  suitable  for  a  seed 
A B  bed.  Where,  how- 
ever, a  garden  has 
o  been  established 
some  years  it  will 
F  be  an  advantage  to 
deepen  the  soil,  as 
distinct  from  the 
subsoil,  by  bring- 
ing the  second 
spade's  depth  to 
the  surface. 

In  the  process 
of  digging  the  soil 
is  loosened  so  as  to 
permit  the  plant 
roots  to  forage 
freely  throughout 
the  soil  which  is 


H 


FIG.  52. — Arrangement  of  ground  for  bastard  trenching. 


within  their  reach.  This  is  specially  important  in  the  early 
stages  of  growth  when  any  circumstance  which  tends  to  check 
the  growth  of  the  plant  has  a  particularly  harmful  effect.  When 
the  plant  is  thoroughly  established  in  the  soil  it  is  able,  and  in 
fact  does,  send  down  its  roots  far  below  the  level  reached  by 
spade  cultivation.  In  the  process  of  digging,  moreover,  atmos- 
pheric oxygen  is  introduced  into  the  soil  spaces,  and 
provision  is  thus  made  for  the  supply  of  oxygen  to  the  roots, 
without  which  they  would  die.  Oxygen  is  required  too  for  the 
bacteria  in  the  soil,  which  in  a  number  of  ways  are  necessary 
for  fertility.  Any  substances  not  fully  oxidised,  as,  for  example, 


TILLAGE  OPERATIONS  AND  MANURING          in 

sulphides  and  lower  oxides  of  iron,  are  converted  by  oxygen 
into  harmless  sulphates  and  higher  oxides.  In  a  soil  which 
has  been  loosened  by  digging,  water  percolates  more  freely.  The 
exposure  of  fresh  surfaces  to  the  action  of  atmospheric  oxygen, 
carbonic  acid,  and  water  results  in  bringing  into  solution  small 
quantities  of  mineral  salts  necessary  to  plant  life,  and  this  is 
assisted  by  the  mechanical  effect  of  alternations  of  heat  and 
cold  on  the  soil  particles.  This  mechanical  effect  is  especially 
marked  in  the  case  of  frost  action,  and  for  this  reason  autumn 
digging  is  of  great  importance.  Water  expands  about  one- 
twelfth  of  its  volume  on  freezing,  and  the  result  is  that  any 
compound  particle  of  soil  containing  interstitial  water  is,  on 
exposure  to  a  temperature  at  or  below  the  freezing-point  of  water, 
subjected  to  a  powerful  disintegrating  force  far  exceeding  any 
that  can  be  directly  exercised  by  an  implement  of  tillage.  The 
results  of  this  disintegration  are  most  marked  on  strongly  cohesive 
clay  particles,  which  after  exposure,  first  to  frost  and  subsequently 
to  a  higher  temperature,  break  down  and  form  a  tilth  exceed- 
ingly suitable  for  a  seed  bed.  It  is  important  that,  when  such  a 
surface  has  been  produced,  there  should  be  no  subsequent  tillage 
which  will  destroy  the  tilth.  The  surface  should  be  touched 
only  with  the  rake  or  hoe.  It  is  desirable  in  autumn  tillage  to 
expose  as  large  a  surface  of  the  soil  as  possible  to  the  action  of 
frost,  and  hence  ground  dug  at  this  period  of  the  year  with  the 
intention  of  leaving  it  until  the  spring  should  be  as  rough  as 
possible.  The  more  lumpy  it  is  the  greater  will  be  the  area 
exposed  to  frost  action.  For  rather  heavy  soils  the  process  of 
ridging  in  the  autumn  may  be  adopted.  This  operation  is  carried 
out  by  means  of  the  spade,  and  consists  in  digging  out  a  series 
of  parallel  rectangles  equal  in  width  to  twice  that  of  the  spade, 
and  laying  the  soil  thus  dug  out  in  a  series  of  parallel  ridges 
occupying  the  centre  line  of  each  rectangle.  Only  a  moderate 
depth  of  soil  should  be  thus  dealt  with,  otherwise  the  ridges  will 
be  too  large  to  be  raked  down  in  the  spring.  Apart  from  the 
mechanical  result  obtained  by  ridging,  the  exposure  of  a  large 
volume  of  surface  soil  to  a  low  temperature  will  result  in  the 
destruction  of  many  grubs  of  hurtful  insects. 

In  considering  the  mechanical  effect  of  change  of  temperature 


ii2  THE  BOOK  OF  NATURE  STUDY 

on  soil,  it  must  be  borne  in  mind  that  the  soil  does  not  consist 
of  particles  of  a  uniform  size,  that  the  particles  are  coated  with 
films  of  water,  and  that  the  particles  are  cemented  together  with 
a  small  quantity  of  a  colloidal  substance.  When,  therefore,  a 
mass  of  soil  is  exposed  to  alternations  of  cold  and  heat,  there 
are  different  pressures  in  different  directions,  which  cause  the 
mass  to  split,  not  into  its  ultimate  particles,  but  into  compound 
particles,  and  it  is  the  production  of  these  compound  particles 
which  constitutes  one  of  the  principal  objects  promoted  by 
tillage. 

Next  to  the  spade,  the  hoe  is  probably  the  most  generally 
important  garden  tool.  There  are  two  main  kinds  of  hoes,  the 
draw  hoe,  which,  as  the  name  indicates,  is  used  by  pulling  it 
towards  the  worker,  and  the  Dutch  hoe,  in  which  a  pushing 
motion  is  adopted.  The  latter  is  probably  the  more  generally 
useful  for  schoolboys.  The  most  obvious  use  of  the  hoe  is  for 
severing  the  roots  of  weeds.  The  draw  hoe  is  also  used  in  ridging 
up  rows  of  plants,  and  sometimes  for  making  drills  for  seeds. 
In  a  dry  season,  whether  in  spring  or  summer,  the  production  with 
the  hoe  of  a  surface  mulch  of  loose  soil  is  of  great  benefit  in 
preventing  evaporation  by  sun  and  wind  of  water  from  the  soil. 
The  shallow  coating  rapidly  becomes  dry,  but  it  protects  the 
under  undisturbed  surface  from  evaporation,  and  thus  preserves 
the  store  of  moisture  in  the  soil. 

It  may  be  useful  at  this  point  to  notice  the  effect  on  soil 
moisture  of  treading  the  soil  down.  This  effect  is  twofold.  In  the 
first  place,  the  firmer  and  more  even  surface  has  less  tendency 
than  a  loose  surface  to  become  dried  by  sun  and  wind  ;  in  the 
second  place,  the  consolidation  of  the  soil  by  treading  promotes 
the  passage  of  water  upwards,  the  drier  soil  being  brought  into 
closer  contact  with  the  moister  subsoil.  Thus  the  result  is  a 
better  supply  of  moisture  just  below  the  surface,  which  supply 
is  necessary  for  the  germination  of  shallow  drilled  seeds.  The 
effect  of  treading  is  only  temporary,  and  a  firmly  pressed  soil,  in 
the  long  run,  loses  more  water  by  evaporation  than  a  looser  soil, 
but  this  does  not  matter  so  long  as  the  object  of  an  immediate 
supply  of  moisture  to  the  seed  and  the  tender  seedling  is  secured. 


Draivn  by  Lilian  Stannard 


A  ROCK  GARDEN 


CHAPTER  VIII 

MULTIPLICATION  OF  PLANTS 

SEEDS. — THE  commonest  method,  whether  in  nature  or  in  the  field 
and  garden,  for  increasing  the  number  of  plants  is  by  seeding,  and 
on  this  account,  and  also  because  seeds  lend  themselves  to  a 
variety  of  simple  but  instructive  experimental  work,  it  is  desirable 
that  the  boys  or  girls  should  make  some  preliminary  observations 
of  the  conditions  of  germination,  and  on  the  germinative  capacity 
of  various  species  of  seeds.  For  this  purpose  it  is  best  as  a  rule  to 
select  large  seeds,  such  as  those  of  the  Broad  Bean,  Pea,  or  Scarlet 
Runner.  For  the  study  of  the  structure  of  a  seed,  peas  may 
be  soaked  in  water  for  a  few  hours  in  order  to  soften  them, 
and  then  dissected,  so  as  to  show  the  seed  coat,  the  seed  leaves, 
the  plumule,  and  the  radicle.  Drawings  should  be  made.  To 
show  the  changes  resulting  from  germination,  other  seeds  should 
be  placed  between  pieces  of  moist  blotting  paper  or  flannel,  and 
kept  in  a  fairly  warm  room.  If  some  of  the  seeds  are  just  covered 
with  sand  in  a  flower  pot,  and  kept  moist  and  warm,  the  way 
in  which  the  seedling  roots  itself  in  the  soil  can  be  studied.  To 
show  the  effect  of  temperature,  one  set  of  seeds  may  be  placed 
in  a  cold  room  and  the  other  in  a  warm  room  ;  the  conditions 
being  otherwise  the  same,  the  growth  in  the  latter  case  will  be 
much  more  rapid.  It  is  a  little  more  difficult  to  demonstrate  the 
necessity  for  oxygen,  but  if  a  supply  of  carbon  dioxide  is  available 
this  may  be  done  by  moistening  the  seeds,  placing  them  at  the 
bottom  of  a  flask,  and  passing  the  washed  gas  through  the  flask 
for  a  quarter  of  an  hour.  The  flask  is  then  quickly  corked,  and 
should  be  kept  in  a  warm  place. 

It  is  easy  and  instructive  to  determine  the  germinative 
capacity  of  various  samples  and  species  of  seeds.  To  do  this, 
we  take  an  exact  and  convenient  number  of  seeds  (fifty  or  one 
hundred),  place  them  between  two  pieces  of  flannel  or  blotting 

VOL.   V. — 8 


U4  THE  BOOK  OF  NATURE  STUDY 

paper  on  a  tile  which  lies  in  a  dinner  plate  containing  a  little 
water.  The  whole  is  left  in  a  warm  place  (60°  to  65°  Fahr.) 
for  not  less  than  ten  days,  care  being  taken  that  the  water  in 
the  plate  is  replenished  if  necessary,  and  that  the  flannel  or 
blotting  paper  is  maintained  in  a  moist  condition  without  being 
soaked.  At  the  end  of  the  period  the  number  of  germinated 
seeds  is  counted  and  expressed  as  a  percentage.  The  experiments 
will  be  more  instructive  if  a  variety  of  seeds  are  dealt  with.  For 
example,  three  pupils  might  work  with  Carrot  seed  (these  are 
really  fruits),  three  with  Parsnip  seed  (also  really  fruits),  three 
with  Cabbage  seed,  three  with  Peas,  and  so  on.  By  arranging 
for  at  least  three  samples  of  one  kind  of  seed  to  be  tested  the 
accuracy  of  the  work  is  ensured,  while  the  natural  differences  in 
germinative  capacity  of  the  various  seeds  will  also  be  brought 
out.  Thus  it  will  probably  be  found,  in  the  case  of  samples  of 
average  excellence,  that  the  percentage  of  germinated  Cabbage 
seed  will  be  about  three  times  that  of  the  Parsnip  seed,  and  that 
Carrot  seed  comes  somewhere  about  midway  between  these.  If 
a  sufficiently  large  number  of  species  are  observed  an  interesting 
table  of  results  can  be  constructed. 

For  practice  in  identifying  seeds  the  teacher  should  keep 
as  many  different  sorts  of  seeds  as  he  can  procure,  in  small  pill 
boxes,  to  be  distributed  occasionally  to  the  class.  The  supply 
will  require  to  be  replenished  every  second  year  as  a  rule,  because 
old  seeds  lose  their  brightness  and  plumpness  if  kept  longer  than 
that  time.1 

1  The  writer  finds  that  Messrs.  Sutton  &  Sons,  of  Reading,  supply  seeds  of  the 
following  species  and  varieties  in  small  glass  tubes  with  metal  caps  at  three  shillings 
per  dozen  tubes.  Small  bags  of  seeds  for  refilling  the  tubes  are  supplied  by  them  at 
one  smiling  and  sixpence  per  dozen  bags. 

Achillea  Millefolium  Festuca  elatior 

Agrostis  stolonifera  ,,         heterophylla 


Alopecurus  pratensis 
Anthoxanthum  odoratum 
Avena  elatior 

flavescens 


Bromus  inermis  Lolium  italicum 
„        Schraederi  ,,       perenne 

Cynosurus  cristatus  „        annuum 

Dactylis  glomerata  Phleum  pratense 

Festuca  duriuscula  Poa  aquatica 


ovina 

ovina  tenuifolia 

pratensis 

rubra 


SEEDS 


The  soil  of  a  seed  bed  must  be  composed  of  fairly  fine  particles, 
neither  too  loose  nor  too  compact ;  it  must  be  moderately  moist, 
and  must  be  at  a  temperature  (which  varies  with  different  species 
of  seeds)  suitable  for  germination.  If  excess  of  water  be  present 
it  is  clear  that  the  interspaces  of  the  soil  will  be  occupied  by 
water  to  the  exclusion  of  air,  which  is  essential  both  for  germination 
and  for  root  growth.  If  the  soil  is  not  sufficiently  fine  the  seed 
may  find  its  way  too  deeply  into  the  soil,  and  also  the  roots  of 
the  seedling  plant  may  fail  to  come  into  sufficiently  close  contact 
with  the  soil  particles  to  obtain  from  them  the  full  necessary 
supply  of  mineral  food. 

Definite  rules  respecting  the  depth  at  which  various  seeds 
should  be  sown  cannot  be  given,  but,  speaking  generally,  the 
smaller  the  seed  the  more  shallow  should  it  be  planted.  Very 
fine  seeds  should  be  just  covered  with  soil,  while  peas  and  beans 
may  be  covered  to  a  depth  of  one  and  a  half  to  two  inches. 


Poa  nemoralis 
,,  pratensis 
,,  trivialis 
,,  serotina 
Elymus  arenarius 
Ammophila  arundinacea 
Trifolium  pratense 

„  „      perenne 

„          repens  perenne 

,,          hybridum 
Medicago  lupulina 
Trifolium  minus 

„          incarnatum 

,,  „      var.  album 

Vicia  sativa 
Cichorium  Intybus 
Faba  vulgaris 
Pisum  sativum  arvense 
Carum  Carui 
Ervum  Lens 
Melilotus  alba 
Medicago  sativa 
Lotus  corniculatus 
Lotus  major 
Beta  vulgaris 


Brassica  Rapa 

„       oleracea  capitata 

„  „        var.  caulo-rapa 

„       campestris,  var.  Napus 

Daucus  Carota 

Pastinaca  sativa 

Sinapis  nigra 

Spergula  arvensis 

Ornithopus  sativus 

Trigonella  Fcenum-grsecum 

Onobrychis  sativa 

Cytisus  scoparius 

Ulex  europaeus 

Anthyllis  Vulneraria 

Lupinus  luteus 
„       hirsutus 

Linum  usitatissimum 

Poterium  Sanguisorba 

Plantago  lanceolata 

Polygonum  Fagopyrum 

Zea  Mays 

Petroselinum  sativum 

Cannabis  sativa 

Sorghum  saccharatum 
„         vulgare 


Brassica  campestris 

Messrs.  Toogood,  of  Southampton,  are  also  prepared  to  supply  schools  with  tubes 

of  seeds  at  a  cheap  rate. 


n6  THE  BOOK  OF  NATURE  STUDY 

The  multiplication  of  plants  by  means  of  seeds  is  a  sexual 
method  of  reproduction, — that  is  to  say,  it  involves  the  union  of 
two  cells  produced,  so  far  as  flowering  plants  are  concerned, 
in  the  stamen,  or  male  portion  of  a  flower,  and  the  carpel,  or 
female  portion  of  the  flower,  respectively.  The  other  method 
of  multiplication  of  plants  is  by  vegetative  reproduction,  which 
involves  the  separation  from  the  parent  plant  of  a  portion  of 
its  leaf-stem  or  root,  such  portion  developing  roots  and  thus 
becoming  a  new  plant.  The  act  of  separation  may  be  the 
result  of  the  natural  growth  of  the  plant,  or  it  may  be  effected 
artificially. 

THE  CORM. — This  is  really  a  short  underground  thickened  stem 
coated  with  membranous  scales.  To  understand  the  method  of 
reproduction,  dig  up  Crocuses  (Crocus  verni)  in  the  spring,  after 
the  flowers  have  died  down,  and  note :  (a)  at  the  base,  the 
adventitious  roots,  with  possibly  the  remnants  of  the  corm  of 
the  preceding  year;  (b)  above  these,  the  corm  of  the  year, 
which  is  now  shrivelled,  owing  to  its  reserve  substances  having 
been  partly  used  up  in  producing  the  leaves  and  flowers  which 
have  just  withered  ;  (c)  the  new  corm,  which  will  be  mature  by 
the  end  of  the  summer,  and  which  is  being  stored  with  food 
material  for  the  growth  of  the  leaves  and  flowers  of  the  succeeding 
season.  With  the  corm  of  the  Garden  Crocus  compare  the  corm 
of  the  Gladiolus. 

THE  TUBER. — This  is  also  a  stem,  usually  underground,  and 
possessing  small  membranous  scale-leaves  from  whose  axils 
buds  arise.  Dig  up  a  young  potato  plant  in  the  early  summer, 
and  note  that  the  tubers  are  swollen  portions  of  underground 
stems.  Select  a  very  small  tuber,  and  with  the  aid  of  a  magnifying 
glass  make  out  the  scale-leaves  near  the  "  eyes  "  of  the  tuber. 

THE  BULB. — A  bulb  consists  of  a  relatively  short  stem  which 
is  enveloped  by  a  number  of  fleshy  scale-leaves.  The  essential 
difference  between  a  bulb  and  a  corm  is  that  the  reserve  material 
is  in  the  former  stored  in  the  scale-leaves,  and  in  the  latter  in 
the  stem.  Dig  up  a  growing  Onion,  Hyacinth,  or  Tulip,  and 


THE  RUNNER  117 

cut  a  vertical  section  of  the  whole  plant,  noting  the  roots,  short 
stem,  scale-leaves,  and  foliage-leaves. 

THE  RUNNER. — Good  examples  of  these  are  found  in  the 
Strawberry  and  Creeping  Crowsfoot.  The  runner  is  a  creeping 
stem  with  long  internodes.  At  the  nodes  are  produced  a  tuft  of 
shoots  and  adventitious  roots.  These  roots  attach  themselves 
to  the  soil,  and  the  internode  ultimately  decays. 

The  above  are  the  principal  ways  in  which  a  plant  reproduces 
itself  vegetatively.  The  chief  artificial  methods  of  vegetative 
reproduction  are  effected  by  means  of  division,  layers,  cuttings, 
grafting,  and  budding. 

Nearly  all  woody  plants  at  some  period  or  other  in  their 
growth  give  rise  to  branches  from  underground  points  in  their 
stems.  These  branches  grow  in  an  oblique  direction  towards  the 
surface,  and  when  they  reach  it  develop  leaves  above  ground  and 
adventitious  roots  underground.  Such  a  growth  is  very  appro- 
priately termed  a  "  sucker/'  since  it  frequently  robs  the  parent  of 
nourishment.  Ultimately  the  portion  of  the  stem  which  connects 
the  sucker  with  the  parent  plant  rots  away,  but  this  process  is 
hastened  by  the  gardener,  who  cuts  through  the  sucker  at  a  point 
below  its  roots.  This  method  of  increasing  the  number  of  plants 
is  commonly  employed  in  the  case  of  perennial  flowering  plants. 
For  purposes  of  study,  note  the  suckers  of  Raspberry,  Rose,  and 
Plum  trees.  Dig  out  the  soil  around  one  of  these,  so  as  to  see 
that  the  sucker  arises  from  a  subterranean  portion  of  the  stem, 
and  to  observe  the  adventitious  roots. 

If  we  cut  off  a  portion  of  the  stem  of  a  plant,  insert  the  cut 
portion  in  the  soil,  and  keep  it  moist  and  warm,  the  cutting  will 
in  most  cases  "  strike/'  That  is  to  say,  adventitious  roots  will  be 
formed  at  the  node  immediately  above  the  cut,  provided  this  node 
is  covered  by  the  soil.  A  similar  formation  of  roots  can  be  induced 
in  the  severed  leaves  of  Begonias  and  Gloxinias,  and  in  the  roots 
of  Pelargoniums.  Moreover,  it  is  not  necessary  to  separate  the  stem 
completely  from  the  parent  plant,  for  if  the  stem  is  bent  downwards 
and  one  portion  of  it  partly  cut  through  and  covered  with  soil, 
adventitious  roots  may  be  produced.  Detailed  examples  will  now 
be  given  of  the  ways  in  which  these  facts  are  utilised  in  gardening. 


n8 


THE  BOOK  OF  NATURE  STUDY 


CUTTINGS. — Two  distinct  classes  of  cuttings  must  be  dis- 
tinguished, namely,  cuttings  of  woody  stemmed  plants  and  cut- 
tings of  soft  stemmed  plants.  Woody  stems,  as  a  rule,  contain 
a  larger  store  of  reserve  food  material  than  do  herbaceous  stems. 
Moreover,  in  the  case  of  the  former  less  water  is  lost  by  transpira- 
tion from  the  stem.  The  propagation  of  woody  plants  by  this 
method  is  therefore  a  rather  simpler  operation  than  in  the  case 
of  plants  with  herbaceous  stems.  For  illustrative  purposes  any 
of  the  following  plants  may  be  selected  :  Privet,  Whitethorn,  Lilac, 
Lavender,  Barberry,  Syringa  (Philadelphus),  or  Laurel.  Select  a 


FIG.  53. — Propagating  Roses  from 
Spring  Cuttings.  A,  cutting  with 
a  heel,  severed  beneath  a  joint ;  B, 
point  of  cutting  retained  ;  C,  the 
cutting  inserted. 


FlG.  54. — Propagating  Roses  from 
Autumn  Cuttings.  A,  suitable 
shoot ;  B,  cutting  prepared  for 
insertion ;  C,  cutting  inserted, 
with  its  base  on  a  layer  of  sand. 


portion  of  the  garden  where  the  soil  is  good  and  has  been  recently 
cropped.  There  should  be  no  undecomposed  farmyard  manure  in 
it.  Mark  off  a  rectangular  portion  four  feet  wide  and  twelve  feet 
long.  This  will  be  sufficient  for  a  hundred  cuttings.  Dig  over 
the  rectangle  a  week  or  a  fortnight  before  the  cuttings  are  to 
be  inserted,  so  as  to  give  the  soil  time  to  settle,  and  just  before 
planting  tread  the  soil  all  over  so  as  to  make  it  firm.  With  the 
aid  of  the  garden  line  trace  four  lines  on  the  bed  at  a  distance 
of  one  foot  apart,  and  along  these  lines  make  small  trenches  about 
four  inches  deep,  and  so  that  one  side  of  each  trench  is  strictly 
vertical.  To  provide  for  aeration  and  drainage  in  the  case  of  a 
heavy  soil,  sprinkle  a  layer  of  sand  along  the  bottom  of  the  trench. 


CUTTINGS  119 

In  taking  the  cuttings  do  not  sever  them  from  the  parent  plant 
by  means  of  a  knife,  but  break  off  side  shoots  close  to  the  main 
shoot,  so  as  to  leave  what  gardeners  call  a  "  heel,"  i.e.  an  oval- 
shaped  base.  Trim  the  ragged  edges  of  this  base,  and  place  the 
trimmed  shoots  upright  in  the  trench,  taking  care  that  the  base 
is  pressed  firmly  against  the  sanded  bottom.  Having  thus 
carefully  placed  all  the  cuttings  in  position,  at  a  distance  from 
each  other  of  six  inches,  shovel  the  earth  into  the  trench,  with 
the  foot  treading  it  firmly  against  the  cuttings,  and  then  rake 
lightly  between  the  rows.  This  operation  is  carried  out  in  the 
early  autumn.  In  the  following  spring  one  or  two  cuttings  may 
be  dug  up  for  examination,  and  after  shaking  off  the  soil  from 
the  base  the  adventitious  roots  should  be  noted,  and  a  drawing 
made.  Note  also  the  protective  callus,  partly  covering  the  cut 
surface  and  produced  by  the  cambium.  By  the  following  spring 
—that  is  to  say,  about  twenty  months  from  the  date  of  planting 
—a  good  mass  of  roots  will  have  been  produced,  and  the  plants 
will  be  ready  for  placing  in  their  permanent  quarters.  In 
removing  them  the  ball  of  earth  enclosed  by  the  roots  should 
be  disturbed  as  little  as  possible.  The  rooted  cuttings  of  Thorn 
and  Privet  may,  if  necessary,  be  used  for  making  a  hedge,  and 
for  this  purpose  should  be  planted  in  a  double  row  at  a  distance 
of  three  inches  between  the  plants  and  six  inches  between  the 
rows.  The  Syringa,  Laurel,  or  Lilac  plants  may  be  planted  in 
corners  of  the  garden.  The  Lavender  plants  may  either  be  dis- 
tributed among  the  students'  plots  or  used  to  make  a  Lavender 
bed,  in  which  case  they  are  planted  in  rows,  giving  them  a  space 
of  fifteen  inches  each  way.  It  will,  of  course,  be  understood 
that  it  is  not  essential  when  planting  the  cuttings  to  set  apart 
a  separate  bed  for  the  purpose,  as,  if  thought  fit,  each  pupil  may 
plant  half  a  dozen  on  his  or  her  own  individual  plot. 

As  indicated  above,  the  propagation  of  herbaceous  perennials 
by  cuttings  requires  rather  more  skill  and  attention.  The  soil 
must  be  fertile  and  well  drained,  and  we  shall  require  the 
assistance  of  the  hot-bed  to  promote  adequate  root  formation 
before  the  winter  comes  on.  The  operation  should  be  effected 
rather  earlier  than  in  the  case  of  woody  perennials,  and  not  later 
than  the  middle  of  September.  Six-inch  flower  pots  may  be 


120 


THE  BOOK  OF  NATURE  STUDY 


conveniently  employed,  and  these  are  half  filled  with  pieces  of 
broken  pot  to  ensure  free  access  of  air,  and  over  this  is  spread 

a  thin  layer  of  decayed  leaves.  Into 
the  pots  is  firmly  pressed  a  potting 
mixture  composed  of  two  parts  of 
"  loam,"  two  parts  of  leaf -mould, 
and  one  part  of  sharp  white  sand. 
With  a  sharp  knife  take  the  cuttings 
from  strong  side  shoots  just  below 
a  node,  and  trim  off  the  lower  leaves 
from  the  cutting.  Five  or  six  such 
cuttings  may  be  planted  in  a  six- 
inch  pot.  In  planting  them,  the 
essential  point  to  observe  is  to  make 
FIG.  55.— Propagation  by  Cuttings,  sure  that  the  soil  is  pressed  firmly 
A,  cuttings  in  a  pot ;  B,  pots  of  against  the  base  of  the  cutting. 

cuttings  in  a  frame.  ATT-.-U  n    J--U-LI  t,    t 

With  a  small  dibble  as  many  holes 

are  made,  equidistant  from  each  other  and  from  the  circumference 
of  the  pot,  as  there  are  cuttings.  In  the  case  of  small  cuttings, 
such  as  those  of  Lobelia,  these  holes  should  be  only  about  one  to 
one  and  a  half  inches  in  depth.  Insert  the  cuttings  one  by  one, 
and  as  each  is  placed  in  the  hole  insert  the  dibble  in  the  soil  a 
little  on  one  side,  so  as  to  press  the  soil  firmly  against  the  length 
and  base  of  the  cutting. 

Herbaceous  cuttings  have  little  reserve  food  material  in  their 
stems  and  leaves,  and  tend  also  to  lose  relatively  considerable 
quantities  of  water  by  transpiration  from  the  leaves  and  stem. 
If  too  much  water  is  thus  lost  before  the  cutting  produces  roots 
it  will  wilt  and  die.  Subsequent  treatment  aims  accordingly  at 
reducing  transpiration  and  at  inducing  rapid  formation  of  roots. 
The  three  conditions  which  favour  root  formation  in  these  circum- 
stances are  warmth,  moisture,  and  oxygen  at  the  cut  surface. 
When  the  cuttings  have  been  planted  we  water  them  well,  and 
transfer  to  a  hot-bed.  The  hot-bed  must  have  been  prepared  some 
days  beforehand.  At  least  two  loads  of  good  horse  manure  is 
required  even  for  a  small  frame.  A  rectangular  area  one  foot 
longer  and  one  foot  wider  than  the  frame  is  marked  on  the 
ground,  and  covered  with  a  layer  of  manure.  This  is  well  trodden 


CUTTINGS  121 

down,  and  a  thin  layer  of  dead  leaves  is  then  sprinkled  over  it. 
The  alternate  layers  of  manure  and  leaves  are  repeated  until  all 
the  manure  has  been  utilised.  It  is  important  that  the  heap 
should  be  trodden  down  as  firmly  as  possible.  The  object  of 
this,  and  also  of  the  leaves,  is  to  reduce  the  rate  of  fermentation, 
and  thus  to  maintain  a  moderate  temperature  for  a  considerable 
period.  The  rise  in  temperature  is  in  effect  an  oxidation  of  the 
substance  of  the  manure  heap  through  the  agency  of  various 
species  of  bacteria.  By  treading  the  heap  down  we  reduce  the 
amount  of  air  in  the  heap,  and  so  reduce  the  speed  of  oxidation. 
The  action  of  the  leaves  is  mainly  one  of  dilution.  On  the  heap 
thus  prepared  the  frame  is  placed,  and  inside  is  spread  a  layer 
of  ashes  to  a  depth  of  three  inches,  in  which  we  can  plunge  the 
pots  to  a  suitable  depth  for  a  steady  supply  of  warmth  to  the 
cuttings.  During  the  first  two  or  three  days  there  will  be  a 
considerable  rise  in  temperature,  as  observed  by  means  of  a 
thermometer  placed  inside  the  frame,  and  most  of  the  oxygen 
in  the  heap  will  be  used  up.  When  this  stage  is  reached  the 
fermentation  processes  depend  mainly  on  the  infiltration  of  air 
from  the  outside,  the  processes  therefore  slacken  in  intensity, 
and  the  temperature  falls  a  little.  At  the  end  of  about  five 
days  from  the  time  of  making,  the  temperature  is  steady,  and 
the  pots  containing  the  cuttings  may  be  plunged  in  the  ashes. 
To  reduce  transpiration,  the  atmosphere  of  the  frame  must  be 
maintained  moderately  moist  by  watering,  and  for  the  same 
reason  direct  sunlight  must  be  excluded.  For  the  first  fortnight 
the  frame  is  opened  an  inch  for  half  an  hour  daily  to  admit 
air.  The  plants  are  then  gradually  hardened  off  by  partly  opening 
the  frame  during  the  warm  part  of  the  day,  and  finally  are 
transferred  to  the  greenhouse  or  room  where  the  temperature 
throughout  the  winter  is  not  allowed  to  fall  below  40°  Fahr. 

If  a  hot-bed  is  not  available,  cuttings  may  also  be  taken  in 
the  spring,  although  in  that  case  the  time  available  for  the 
plant  to  establish  itself  before  flowering  is  shorter.  Pinks,  such 
as  the  Clove  Pink  and  "  Mrs.  Sinkins "  Pink,  may  be  treated 
in  this  way.  The  method  of  taking  and  of  potting  the  cuttings 
is  the  same.  Indeed,  cuttings  of  Pinks  may  be  planted  out  at 
once  on  the  border,  provided  this  is  well  shaded  from  the  sun. 


122 


THE  BOOK  OF  NATURE  STUDY 


The  cuttings  are  taken  in  March,  planted  at  a  distance  of  one 
foot  from  each  other,  and  well  watered. 

PROPAGATION  BY  DIVISION.  —  This  is  a  very  simple  operation. 
Experience   shows    that  the  smaller    perennial   herbaceous  and 

woody  flowering  plants  are  at  their 
best  during  the  first  three  or  four  years 
after  planting.  At  the  end  of  that 
time  the  plant  usually  deteriorates 
from  a  horticultural  point  of  view. 
It  will  have  become  straggling  and 
"  leggy/'  and  the  proportion  of  flowers 
to  the  size  of  the  plant  will  have  de- 
creased. Part  of  this  effect  is  due  to 
the  natural  growth  of  the  plant,  and 
part  to  exhaustion  of  the  available 
mineral  matter  in  the  soil.  In  these 

FIG.    56.-  Lifting    and    Dividing        .  .  . 

Clumps.    Roots  A,  A  are  not    circumstances  it  is  desirable  to  transfer 
broken  when  a  fork  is  used;    the  plant  to  another  position,  and  at 


several  portions,  each  of  which  may 
be  separately  planted.  The  original  plant  is  dug  up  with  a  fork, 
and  it  will  then  be  found  that  adventitious  roots  will  have  been 
produced  on  the  underground  portions  of  most  of  the  shoots. 
These  may  be  torn  apart  with  one's  hands,  the  coarser  shoots 
being  discarded  and  the  younger  ones  trimmed  and  replanted, 
care  being  of  course  taken  that  each  shoot  selected  for  replanting 
bears  some  roots.  Propagation  by  division  should  be  carried  out 
in  October,  when  the  plant  is  entering  upon  its  resting  stage. 

LAYERING.  —  This  is  an  operation  intermediate  between 
propagation  by  cuttings  and  propagation  by  division.  In  the 
former  case  adventitious  roots  are  developed  after  the  cutting 
is  taken  ;  in  the  latter  case,  before  the  separation  from  the  parent 
plant.  In  layering  we  induce  the  formation  of  adventitious 
roots  in  a  shoot  by  partially  severing  the  shoot  from  the  parent. 
The  essence  of  the  method  consists  in  cutting  partly  through  a 
shoot,  just  below  a  node,  and  then  bending  the  shoot  down, 


LAYERING 


123 


fastening  it  to  the  ground  by  means  of  a  peg  of  some  kind,  and 
then  covering  the  cut  portion  with  moist  soil.  Roots  are  pro- 
duced at  the  node,  and  when  well  developed  the  shoot  may  be 
completely  cut  through  and  planted  out.  A  very  large  number 
of  specie's  of  plants  may  be  propagated  in  this  way,  and 
the  students  should  be  encouraged  to  experiment  on  a  variety 
of  herbaceous  plants,  shrubs,  and  bushes,  not  necessarily  confining 
themselves  to  plants  of  the  garden.  They  should  notice  that 
the  farm  labourer,  when  making  or  renovating  a  thorn  hedge, 
makes  use  of  the  two  methods  of  propagation,  by  cuttings  and 
by  layers.  The  period  which 
should  be  allowed  to  elapse  be- 
tween layering  and  separating 
the  rooted  shoot  is  different  for 
different  sorts  of  plants.  Gener- 
ally speaking,  herbaceous  plants 
may  be  layered  in  July,  and  the 
shoots  taken  off  in  September. 
Woody  shrubs  should  be  layered 
in  autumn,  and  not  severed  until 
the  following  August  or  Septem- 
ber. For  detailed  description 
we  may  select  the  propagation 
of  Carnations,  which  is  usually 
effected  by  layering  at  the  end  of 
July.  We  require  for  the  purpose 

a  really  sharp  knife,  a  small  quantity  of  potting  soil,  and  small 
wooden  pegs  such  as  may  be  easily  cut  from  any  hedge.  A 
vigorous  side  shoot  should  be  chosen,  and  after  trimming  off  the 
leaves  from  the  lower  portion  of  it  a  node  convenient  for  pegging 
down  should  be  selected.  An  oblique  cut  is  then  made  in  the 
shoot  commencing  a  little  distance  below  the  node  and  extending 
through  the  middle  of  the  stem  up  to,  but  not  through,  the  node. 
The  shoot  is  next  bent  down  so  that  the  cut  portion  rests  firmly 
on  a  small  pressed-down  heap  of  the  potting  soil,  and  is  there 
pegged.  It  is  then  covered  with  some  more  of  the  potting  soil, 
also  firmly  pressed  down,  and  the  mass  of  soil  thoroughly 
moistened.  The  parent  plant  is  also  well  watered,  and  the 


FIG.  57.— Layering  Carnations.— A,  old 
plant ;  B,  young  layer ;  C,  shows  the 
cut  made  with  a  sharp  knife,  lip  of  stem 
kept  open  with  small  pebble  ;  D,  special 
compost ;  E,  border  soil. 


124  THE  BOOK  OF  NATURE  STUDY 

watering  must  be  repeated  every  few  days  if  the  weather  is  dry. 
Under  these  conditions  adventitious  roots  are  produced  at  the 
node  within  a  month,  and  in  two  months'  time  from  the  date  of 
layering  these  roots  will  be  sufficiently  well  developed  to  permit 
of  the  separation  of  the  shoot  from  the  parent.  The  rooted 
shoot  is  then  potted  in  good  potting  soil,  and  placed  in  a  cold 
frame  or  on  a  window-sill.  Care  must  be  taken  during  the  first 
few  days  after  potting  that  the  plant  is  not  exposed  to  conditions 
which  favour  much  transpiration,  otherwise  the  plant  will  lose 
more  water  than  can  be  supplied  by  the  roots,  and  will  wilt. 
The  potting  mixture  should  not  be  dry,  and  the  plant  should 
not  be  watered  for  the  first  four  days  after  potting.  During  the 
winter  the  plants  are  kept  preferably  in  the  cold  frame  and 
protected  from  frost.  If  a  cold  frame  is  not  available  the  young 
plants  may  be  kept  indoors  during  the  winter,  and  planted  out  in 
the  beds  at  the  end  of  March  ;  or  again,  the  layered  cuttings  may 
be  planted  out  in  a  sheltered  bed  out  of  doors  in  the  autumn,  but 
they  will  then  require  to  be  protected  with  matting  during 
severe  winter  frosts. 


CHAPTER    IX 

VEGETABLE  CULTURE 

AN  abundant  supply  of  good  fresh  vegetables  throughout  the  year 
is  essential  for  health,  and  therefore,  whatever  other  departments 
of  horticultural  work  are  undertaken  in  the  school  garden, 
vegetable  culture  ought,  except  in  the  case  of  a  school  in  the 
centre  of  a  large  urban  area,  to  take  the  first  place. 

Continuity  of  supply  is  important,  and  the  young  student 
should  therefore  be  so  instructed  that  he  may  have  exact 
information  as  to  the  time  of  planting  and  the  length  of  the 
period  during  which  the  ground  is  occupied  by  the  various  crops 
commonly  grown  in  the  vegetable  garden.  He  should  thus  be 
able  to  say  at  once  what  crops  may  be  expected  to  be  occupying 
the  garden  at  any  time  of  the  year.  It  is  only  when  the  worker 
has  clear  and  exact  knowledge  under  these  heads  that  he  is  able 
to  utilise  the  ground  at  his  disposal  to  full  advantage,  and  to 
provide  a  satisfactory  supply. 

It  is  of  some  importance  to  arrange  for  a  rotation  of  crops, 
though,  provided  the  garden  soil  is  good,  this  is  not  so  necessary 
as  in  the  case  of  farm  crops.  In  a  good  rotation  of  crops  a  shallow 
rooted  plant  is  succeeded  by  one  which  roots  deeply ;  and 
further,  plants  of  closely  allied  species  should  not  succeed  each 
other,  for  the  reason  that  closely  related  plants  frequently  make 
similar  demands  on  the  mineral  constituents  of  the  soil,  and  also 
harbour  the  same  fungoid  and  insect  enemies. 

The  pupils  may  with  advantage  receive  some  instruction  on 
the  food  values  of  the  various  vegetables  cultivated  by  them, 
and  if  the  school  possesses  some  equipment  for  chemistry  they 
may  be  taught  how  to  isolate  and  examine  some  of  the  most 
important  common  constituents.  Microscopic  sections  of 
vegetable  tissue  may  be  examined  for  cellulose,  starch,  protoplasm, 
and  oil  drops.  The  most  abundant  constituent  of  most  vegetables 


126  THE  BOOK  OF  NATURE  STUDY 

is  water.  To  determine  this  amount  very  roughly,  a  very  thin 
slice  of  potato,  apple,  radish,  etc.  may  be  weighed  on  the  ordinary 
balance  used  in  schools  for  elementary  chemical  and  physical 
determinations.  The  slice  is  then  strung  on  a  knitting  needle 
and  placed  in  an  air  oven  maintained  at  a  temperature  of  about 
110°  for  some  hours.  A  very  great  decrease  in  weight  owing 
to  loss  of  water  will  be  observed.  The  results  may  be  compared 
with  those  obtained  similarly  in  the  case  of  slices  of  Brazil  nuts 
or  chestnuts.  The  results,  though  rough,  will  sufficiently  indicate 
the  difference  in  water  contents.  Nuts  and  seeds  contain  from  i 
to  10  per  cent,  of  water,  while  juicy  fruits  and  vegetables  contain 
from  50  up  to  over  90  per  cent. 

Of  the  carbohydrates,  starch  is  present  to  the  extent  of  10 
to  14  per  cent,  in  Potatoes,  while  sugars  are  present  to  about 
the  same  amount  in  ripe  Apples,  Pears,  Grapes,  Strawberries,  and 
Raspberries.  Parsnips  and  Carrots  contain  6  to  10  per  cent, 
of  sugar,  and  Sugar  Beet  contains  15  per  cent.  To  show  the 
presence  of  starch,  peel  a  potato,  and  then  grate  it  on  a  nutmeg 
grater,  allowing  the  grated  portion  to  fall  on  a  piece  of  fine 
muslin  stretched  over  a  glass  jar  or  jug.  By  washing  the  grated 
mass  with  water  the  starch  grains  are  carried  through  into  the 
glass  vessel,  while  the  cellulose  remains  on  the  muslin  as  a  soft 
whitish  mass.  If  the  starch  is  allowed  to  settle  and  the  liquid 
decanted  the  finely  granular  character  of  starch  can  be  easily 
made  out.  Starch  grains  from  various  vegetables  may  be 
examined  under  the  microscope  and  their  appearance  compared. 

Sugars  can,  of  course,  be  detected  in  ripe  fruit  by  the  taste, 
and  their  presence  demonstrated  chemically  by  warming  a  little 
of  the  filtered  expressed  juice  with  Fehling's  solution.  Crystals 
of  sugar  may  also  be  obtained  by  boiling  Carrots,  Parsnips,  or 
Sugar  Beet  in  water,  crushing  the  boiled  mass,  filtering,  and 
evaporating  the  filtrate  to  small  bulk. 

The  presence  of  oil  in  nuts  is  best  shown  by  means  of  thin 
sections  mounted  in  water  and  examined  under  the  microscope. 
Or  we  may  imitate  the  process  of  manufacture  of  agricultural 
"  oilcake,"  by  crushing  seeds  of  rape  or  of  flax,  which  contain 
30  to  40  per  cent,  of  oil.  Many  of  the  proteid  substances  of  plants 
are  soluble  in  water,  and  like  white  of  eggs  are  coagulable  by  heat. 


VEGETABLE  CULTURE  127 

To  demonstrate  the  presence  of  proteid,  we  may  therefore  crush 
succulent  vegetable  tissue,  filter  the  expressed  liquid  into  a  test 
tube  and  warm,  when  a  whitish  precipitate  will  be  produced.  The 
mineral  substance  of  plants  is  contained  in  their  ashes,  part  of  which 
is  soluble  in  water  and  part  (carbonate  of  lime,  etc.)  insoluble. 

To  grow  heavy  crops  of  vegetables  of  good  quality  the  con- 
ditions of  moisture,  temperature,  aeration,  presence  of  mineral 
food  in  an  available  form,  and  absence  of  injurious  substances 
from  the*  soil,  must  be  met.  The  ground  must  therefore  be 
trenched,  unless  this  has  been  done  in  the  previous  year,  and 
well  manured.  The  best  manure  is  farmyard  manure,  this  being 
a  general  manure  ;  that  is  to  say,  it  contains,  either  in  an 
immediately  available  form  or  in  a  form  which  will  gradually 
become  available  within  a  few  months,  those  three  chemical 
elements  which  are  essential  to  plant  life  and  are  shown  by 
experience  to  be  easily  removable  from  the  soil.  These  three 
elements  are  nitrogen,  phosphorus,  and  potassium.  The  four 
remaining  elements  (sulphur,  iron,  calcium,  and  magnesium) 
are  in  practically  all  cases  present  in  sufficient  quantity.  Apart 
from  the  fact  of  its  being  a  general  manure,  farmyard  manure 
keeps  a  heavy  soil  open,  and  thus  ensures  the  presence  of  air 
and  the  passage  of  water.  When  partly  decomposed  under 
the  action  of  soil  bacteria,  it  gives  rise  to  a  dark,  powdery 
substance  termed  humus,  which  possesses  the  property  of  retain- 
ing moisture,  and  consequently  farmyard  manure  is  equally 
valuable  from  its  physical  effect  on  light  sandy  soil.  Stable 
manure  is  drier  and  more  easily  fermentable  than  manure  from 
the  cowshed  or  pigstye.  The  former  is  therefore  the  most  suitable 
for  very  heavy  soils,  and  the  two  latter  for  sandy  soils.  For 
intermediate  types  of  soils  the  difference  in  the  behaviour  is  so 
slight  as  to  be  negligible.  A  soil  which  has  not  previously  been 
used  as  a  garden  ground,  or,  having  been  so  used,  is  in  poor 
condition,  should  receive  a  heavy  dressing  of  farmyard  manure. 
For  farm  purposes,  twenty  tons  per  acre  is  an  average  dressing. 
For  a  garden,  the  soil  of  which  is  poor,  this  amount  may  be  doubled. 
The  ordinary  two-wheeled  farm-cart  will  hold  about  a  ton  of 
farmyard  manure,  and  this,  therefore,  is  the  quantity  which 
may  be  applied  to  every  four  rods  of  the  garden.  This  will  be 


128  THE  BOOK  OF  NATURE  STUDY 

in  no  way  an  exceedingly  heavy  dressing.  If  the  soil  is  heavy 
and  is  to  be  trenched  in  the  autumn,  the  manure  may  with 
advantage  be  mixed  with  the  bottom  layer  of  each  trench.  It  will 
keep  the  soil  open  to  a  good  depth  below  the  surface.  Light  sandy 
soils  are  very  porous  to  heavy  rains,  and  there  is  risk  on  such 
soils  of  valuable  soluble  matter  being  washed  into  the  subsoil  in 
the  winter  and  ultimately  removed  in  the  drainage  waters.  On 
light  soils,  therefore,  the  farmyard  manure  is  best  applied  in 
the  spring,  just  before  the  principal  crops  are  put  in.  There  is 
obviously  no  necessity  to  take  special  precautions  to  keep  sandy 
soils  open,  and  the  manure,  after  being  spread  on  the  surface, 
should  in  these  cases  be  simply  dug  under.  It  will  then  be 
within  reach  of  the  roots  of  the  young  plants.  Old  garden  ground 
is  generally  very  rich  in  humus,  owing  to  the  decay  of  many 
generations  of  plant  roots.  If,  as  is  generally  the  case,  the  humus 
contains  much  humic  acid,  the  soil  is  distinctly  acid,  and  un- 
favourable to  root  and  bacterial  activity.  Humic  acid  is  best 
neutralised  by  a  dressing  of  lime.  The  lime  may  be  in  the  form 
of  very  finely  ground  limestone,  or  better,  quicklime  may  be 
put  in  small  heaps  on  the  garden,  and  just  sufficient  water 
added  to  slake  it,  when  the  lumps  of  quicklime  (thus  converted 
into  calcium  hydrate)  will  break  into  a  fine  powder,  which  should 
be  immediately  spread  over  the  surface  of  the  soil  and  raked, 
or  gently  forked  in.  About  one  bushel  of  lime  per  rod  may  be 
applied.  There  is  not  much  danger  of  an  over-accumulation  of 
humic  acid  in  most  soils  with  sandy  or  gravelly  subsoils,  for  such 
soils  are  sufficiently  aerated  to  permit  the  roots  and  bacteria  to 
flourish.  Light  soils  are,  however,  often  benefited  by  a  dressing 
of  marl  or  other  calcareous  clay,  and  this  dressing  may  profitably 
be  applied  every  six  or  eight  years. 

Farmyard  manure  may  in  many  cases  be  usefully  supple- 
mented by  artificial  mineral  manures,  namely,  nitrate  of  soda, 
sulphate  of  ammonia,  or  nitrate  of  lime  (nitrogenous),  super- 
phosphate of  lime,  or  bone  flour  (phosphatic) ,  and  sulphate  of 
potash  or  kainit1  (potassic).  The  experimental  data  respecting 

1  Kainit  is  mined  from  deposits  occurring  at  Stassfurt  and  elsewhere  in  Germany, 
and  is  composed  of  sulphates  of  potassium  and  magnesium  together  with  chlorides  of 
potassium,  magnesium,  and  sodium. 


VEGETABLE  CULTURE  129 

** 

the  quantity  to  be  applied  and  the  crops  to  which  they  may  be 
applied,  as  well  as  respecting  the  kinds  of  soils  in  which  they  will 
benefit  particular  sorts  of  plants,  are  not  at  present  sufficiently 
complete  for  any  full  and  detailed  rules  to  be  laid  down  as  to  the 
use  of  artificial  ^manures  on  garden  crops.  Generally  speaking, 
nitrates  favour  the  production  of  foliage,  potash  the  production 
of  carbohydrates,  while  phosphates  appear  to  improve  the  quality 
of  the  crop.  Nitrate  of  soda  certainly  tends  to  produce  heavier 
crops  of  cabbages,  and  sulphate  of  potash  in  most  soils  and 
seasons  gives  an  increased  crop  of  potatoes.  Kainit  is  not  so 
good  for  garden  crops,  since  the  considerable  amount  of  magnesium 
which  it  contains  (and  possibly  the  chlorine  also)  appears  to 
exert  a  harmful  effect.  Kainit  may,  however,  be  applied  in 
autumn  on  rather  heavy  soils  which  contain  grubs,  for  it  acts 
as  an  insecticide  as  well  as  a  manure. 

There  is  a  considerable  field  for  simple  experimental  work 
in  school  gardens  on  the  effect  of  various  artificial  manures, 
and  teachers  are  recommended  to  arrange  trial  plots  or  trial 
rows  with  this  object  in  view.  The  quantity  of  artificial  manures 
to  be  applied  may  vary  between  two  and  five  pounds  per  rod. 
Most  of  them  are  fairly  soluble  in  water  (nitrate  of  soda  is  readily 
soluble),  and  they  are  in  consequence  best  applied  as  a  top 
dressing  to  the  young  growing  crop. 

Of  other  manures  used  in  the  vegetable  garden  we  may 
mention  liquid  farmyard  manure,  which  is  a  valuable  form  for 
application  to  cabbage  plants.  Soot  is  sometimes  used  as  a  top 
dressing,  partly  for  the  nitrogen  which  it  always  contains,  and 
partly  to  prevent  attacks  from  slugs.  If  a  bag  of  soot  is  sus- 
pended in  a  tub  of  water,  a  weak  nitrogenous  solution  is  obtained, 
which  may  be  used  for  watering  young  tender  plants.  Guano 
(nitrogenous  and  phosphatic)  is  frequently  applied  as  a  top  dressing 
to  flowers,  but  is  seldom  used  for  manuring  vegetables. 


ARRANGEMENT  OF  THE  VEGETABLE  BEDS. 

As  a  rule  the  rows  of  vegetables  should  run  north  and  south,  be- 
cause in  this  way  only  shall  we  secure  that  each  individual  plant 
receives  its  fair  share  of  sunlight.  For  purposes  of  change  of  ground, 

VOL.   V. — 9 


130  THE  BOOK  OF  NATURE  STUDY 

the  garden  or  (on  the  individual-plot  system)  the  plot  may  be  re- 
garded as  divided  into  three  approximately  equal  portions.  On  the 
first  we  should  grow  leguminous  plants,  such  as  Broad  Beans,  Dwarf 
Beans,  Scarlet  Runners,  and  Peas ;  on  the  second,  Parsnips,  Carrots, 
and  Beet ;  and  on  the  third  portion,  Onions,  Cabbages,  Potatoes, 
and  Turnips.  In  the  following  year  the  positions  of  these  three 
portions  would  be  interchanged.  A  small  portion  of  ground 
must  be  reserved  for  salad  plants,  such  as  Mustard  and  Cress, 
Radishes  and  Lettuces,  while  a  few  flowers  may  be  planted  along 
the  border.  A  small  common  nursery  bed  will  be  required  for 
Cabbages  or  other  crops  requiring  transplanting.  It  is  highly 
important,  if  strong  healthy  plants  are  desired,  that  seeds  should 
always  be  thinly  sown,  whether  in  drills  or  in  beds,  and  for  the  same 
reason  thinning  must  be  carried  out  at  an  early  stage,  and  trans- 
planting, where  required,  should  be  done  as  soon  as  the  plants 
are  big  enough  to  handle,  that  is  to  say,  when  they  are,  roughly 
speaking,  a  couple  of  inches  high. 


THE  CABBAGE  AND  ITS  VARIETIES 

The  Cabbage,  Savoy,  Brussels  Sprout,  Borecole,  Brocoli,  and 
Cauliflower  are  all  derived  from  a  common  parent,  the  Wild 
Cabbage  (Brassica  oleracea),  which  may  be  found  growing  in  the 
south  of  England,  in  Denmark,  and  elsewhere  in  North-West 
Europe.  The  wild  form  most  closely  resembles  the  cultivated 
variety,  Kohlrabi.  The  differences  in  form  between  the  various 
varieties  above  mentioned  depend  upon  differences  in  the  develop- 
ment, either  of  the  stem,  the  inflorescence,  or  the  axillary  buds. 
In  the  case  of  White  and  Red  Cabbage  and  of  the  Savoy  Cabbage, 
the  internodes  of  the  stem  are  short,  and  the  terminal  bud  becomes 
greatly  enlarged,  giving  rise  to  a  closely  packed  head  of  large 
leaves.  The  Savoy  differs  from  the  White  Cabbage  only  in  the 
fact  of  the  leaves  being  wrinkled.  The  internodes  of  the  stem 
of  the  Brussels  Sprout  are  well  developed,  and  the  axillary  buds 
remain  small  and  compact,  like  miniature  Cabbages.  In  Borecole, 
these  buds  branch  into  elongated  leaves.  Brocoli  and  Cauli- 
flowers differ  only  in  the  fact  of  the  latter  being  rather  less  hardy. 
In  both  the  "head"  is  an  inflorescence,  produced  in  the  first 


^  THE  CABBAGE  131 

year  instead  of  the  second,  and  with  much  thickened  branches. 
Cabbages,  Savoys,  Brussels  Sprouts,  and  Borecole  contain  a  very 
high  percentage  of  water  (about  90  per  cent.),  and  their  value  as 
food  depends  mainly  upon  the  fact  that  they  furnish  an  abundant 
winter  supply  of  gre^en  food-stuff.  They  are  all  sown  on  a  seed 
bed,  from  which  they  are  transplanted  as  soon  as  the  young 
plants  are  big  enough  to  be  handled.  The  seed  should  be  sown 
quite  thinly  on  a  fine  seed  bed  previously  watered  if  at  all  dry. 
Thick  sowing  gives  rise  to  weak,  leggy  plants.  The  permanent 
bed  must  be  deeply  dug  and  well  manured,  as  all  members  of  the 
Cabbage  tribe  are  heavy  feeders.  Brocoli  may  be  sown  in  almost 
any  month ;  Brussels  Sprouts  are  usually  sown  in  March,  April, 
and  May  ;  Cauliflowers  are  unable  to  withstand  frost.  Subject  to 
these  remarks,  we  may  say  that  there  are  two  principal  periods 
during  which  the  varieties  of  Brassica  oleracea  may  be  sown, 
namely,  in  March  for  a  winter  supply,  and  in  June  for  a  spring 
supply.  In  planting  out,  the  rows  are  marked  with  the  garden 
line,  and  the  young  plants  dibbled  in,  care  being  taken,  as  with 
the  transplanting  of  all  small  young  plants,  that  the  young  plant 
reaches  the  bottom  of  the  hole.  The  distance  between  the  rows 
should  be  two  feet,  and  this  also  should  be  the  distance  between  the 
plants  in  the  rows,  except  that  in  the  case  of  the  spring  Cabbages 
the  distance  in  the  row  may  be  reduced  to  fifteen  or  eighteen 
inches.  Brocoli,  though  much  hardier  than  Cauliflowers,  surfer 
also  to  some  extent  when  exposed  to  lengthy  periods  of  frost 
succeeded  by  a  rapid  thaw.  Hence  it  is  usual  to  "  heel  "  Brocoli, — 
that  is,  to  bend  them  over  towards  the  north  on  the  approach  of 
bad  weather,  the  object  being  to  prevent  a  too  speedy  thawing 
by  the  sun.  Cabbages  require  to  be  well  watered,  and  they  are 
also  benefited  by  doses  of  liquid  manure  (farmyard)  applied  close 
to  the  roots.  To  preserve  the  soil  moisture  from  evaporation  a 
good  surface  mulch  should  be  maintained  by  means  of  the 
Dutch  hoe.  In  the  following  list  are  given  the  names  of  the  best 
kinds. 

Brocoli — Winter  White,  for  spring  sowing. 

King  of  the  Brocoli,  for  May  sowing. 

Cauliflower — Walcheren,  Sutton's  Purity. 

Brussels  Sprouts — Aigburth. 


132  THE  BOOK  OF  NATURE  STUDY 

Cabbage    Sprouts — Ellams    Early,   Enfield    Market,    Daniel's 

Defiance. 
Savoy  Sprouts — Drumhead,  Perfection. 


THE  POTATO  (Solanum  tuberosum) 

This  vegetable  is  indigenous  in  Chili,  where  it  grows  in  the 
wild  state  at  considerable  heights  above  the  sea  level.  For 
this  reason,  probably,  the  cultivated  Potato  is  found  to  thrive 
on  the  uplands  in  this  country.  The  Spaniards  introduced  it 
into  North  America  from  Chili,  and  Sir  Walter  Raleigh  brought 
it  to  England  late  in  the  sixteenth  century.  The  Potato  plant 
possesses  a  green  herbaceous  aerial  stem,  and  a  short  rhizome 
with  closely  clustered  tuberous  branches  which  constitute  the 
edible  part.  On  the  tubers  are  depressions  arranged  spirally, 
called  the  "  eyes,"  and  in  the  "  eyes  "  are  a  number  of  buds. 
As  in  the  case  of  an  aerial  stem,  the  "  eyes  "  are  more  numerous 
at  the  apex  of  the  tuber.  The  tubers  if  exposed  to  light  develop 
chlorophyll  and  turn  green.  The  tubers  are  classified  by  the 
growers  into  three  divisions,  namely  :  the  round,  the  oval,  and 
the  kidney  shape.  The  tubers  contain  from  18  to  20  per  cent, 
of  starch,  and  it  is  on  the  proportion  of  this  substance  that 
their  value  for  food  depends.  Other  things  being  equal,  the  best 
Potatoes  are  those  containing  abundance  of  starch  grains  packed 
in  large  cells  with  thin  cell  walls. 

The  fruit  of  the  Potato  plant  is  a  berry  containing  numerous 
seeds.  New  varieties  are  obtained  by  sowing  the  seeds  produced 
by  cross  fertilisation  and  propagating  the  tubers  for  four  years, 
when  they  are  large  enough  for  their  value  for  food  purposes 
to  be  determined.  The  tubers  of  the  first  year  are  only  about 
as  large  as  peas.  Potatoes  are  grown  in  immense  quantities  in 
Ayrshire  and  in  Lincolnshire.  The  total  annual  production  in 
the  United  Kingdom  is  about  eight  million  tons. 

The  Potato  is  propagated  by  means  of  the  tubers.  Now,  the 
tuber  is  a  part  of  the  stem,  and  hence,  since  the  life  of  a  plant 
is  limited,  it  follows  that  propagation  by  this  method  cannot 
be  continued  for  an  indefinite  period.  It  follows  from  this  that 
any  given  variety  must  after  a  time  die  out,  and  as  a  matter  of 


THE  POTATO  133 

fact  all  the  varieties  in  cultivation  thirty  years  ago  have 
disappeared.  Twenty-five  to  thirty  years  is  therefore  the 
maximum  duration  of  a  variety.  Owing  to  the  special  methods 
of  rapid  propagation  now  adopted  when  good  varieties  have  been 
raised,  the  duration  of  life  has  been  considerably  shortened,  and 
about  ten  to  fifteen  years  is  the  average  duration  of  life  of  the 
varieties  now  in  use.  The  best  "  seed  "  Potatoes  are  found  to 
be  medium  sized  tubers  (what  gardeners  call  the  "  big-little  "  ones) 
with  shallow  "  eyes "  and  smooth  skins.  Sometimes  larger 
tubers  are  cut  into  two  or  three  pieces  (each  piece,  of  course,  with 
an  "  eye  ")  for  planting  ;  but  these  do  not  give  such  good  results, 
probably  because  of  the  loss  by  evaporation  of  water  across  the 
cut  surface,  which  naturally  hinders  the  growth  of  the  shoot. 
Numerous  experiments  in  various  parts  of  England  have 
demonstrated  the  fact  that  the  largest  yields  are  obtained  from 
seed  procured  either  from  Scotland  or  from  Ireland.  The 
experiments  conducted  by  the  Lancashire  County  Council  showed 
an  increase  of  from  one  to  four  tons  per  acre  in  the  case  of  seed 
obtained  from  Scotland,  as  compared  with  seed  obtained  from 
the  south  of  England.  The  seed  Potatoes  should  be  procured 
early  in  the  spring,  and  should  be  at  once  "  boxed."  That  is  to 
say,  they  are  placed  in  shallow  boxes,  each  box  containing  one 
layer  of  tubers,  and  kept  in  a  shed  or  stable,  where  an  even 
temperature  high  enough  to  cause  the  tubers  to  sprout  is 
maintained.  The  sprouting  must  proceed  in  the  light,  so  as  to 
produce  short  internodes,  and  must  be  so  managed  that  short 
internodes  are  developed  at  the  time  for  planting.  Stems  with 
long  internodes  have  fewer  points  from  which  tuber-producing 
stems  can  arise.  All  but  the  two  strongest  shoots  should  be  rubbed 
off  just  before  planting.  In  the  Lancashire  experiments  above 
referred  to,  sprouted  tubers  gave  an  increased  yield  of  nearly 
two  tons  per  acre  over  the  unsprouted  tubers.  The  best  soil 
for  Potatoes  is  a  deep,  light  loam,  well  drained,  possessing  a  rich 
store  of  well  decayed  organic  matter.  It  is  important  that  the 
soil  should  be  open  enough  to  allow  full  expansion  of  the  tubers. 
Cold  undrained  clay  and  peat  soils  are  the  most  unsuitable  of  all. 
Potatoes  of  the  best  quality  are  not  produced  when  the  soil 
contains  much  undecomposed  farmyard  manure,  and  hence  the 


±34  THE  BOOK  OF  NATURE  STUDY 

best  procedure  is  to  manure  the  preceding  crop  rather  heavily 
with  farmyard  manure,  and  to  apply  to  the  Potato  crop  only 
artificial  manure.  If  farmyard  manure  is  applied  to  the  Potato 
ground,  the  application  should  be  made  in  the  preceding  autumn, 
and  the  manure  dug  in  at  that  time.  If  farmyard  manure  only 
is  applied,  the  quantity  should  be  about  one  cartload  (i.e.  one 
ton)  per  eight  rods  ;  but  if,  as  is  best,  a  dressing  of  artificial  manure 
is  also  given,  this  quantity  should  be  sufficient  for  sixteen  rods. 
The  artificial  manures  should  be  complete, — that  is  to  say,  they 
should  supply  nitrogen,  potash,  and  phosphoric  acid,  and  this  is 
secured  by  a  dressing  at  the  rate  per  rod  of  i  Ib.  of  sulphate  of 
ammonia,  3  Ib.  of  superphosphate  of  lime,  and  i  Ib.  of  muriate 
of  potash.  On  many  garden  soils  rich  in  nitrogen  the  amount 
of  sulphate  of  ammonia  may  be  reduced  by  one-half.  The  three 
artificial  manures  here  recommended  should  be  mixed  together 
immediately  before  planting,  and  sown  broadcast  across  the 
Potato  drills. 

For  a  succession  of  crops,  early,  mid-season,  and  late  plantings 
are  made.  For  early  Potatoes  (which  are  consumed  in  an  immature 
state)  the  best  varieties  at  the  present  time  are  Sharpe's  Victor, 
Button's  Ringleader,  Sir  John  Llewellyn,  and  Ashleaf.  These 
should  be  planted  in  the  middle  of  March.  Main  crop  varieties 
for  planting  from  the  middle  of  April  to  the  early  part  of  May 
are  :  Main  Crop,  Windsor  Castle,  Up-to-Date,  Snowdrop,  Flour- 
ball,  Factor,  Abundance,  British  Queen,  and  Sutton's  Triumph. 

Heavy  soil  should  be  ridged  up  in  the  autumn,  and  the  ridges 
may  then  be  raked  down  level  in  spring,  and  lightly  dug  over 
just  before  planting.  Light  soils  should  be  double  dug  in  spring. 
The  ground  having  been  dug  and  levelled  with  the  rake,  shallow 
trenches,  about  seven  inches  deep  and  two  feet  apart,  are  made 
with  the  spade  and  garden  line,  and  the  artificial  manures  are 
then  sown.  Next,  the  tubers  are  carefully  planted  with  the 
sprouts  pointing  upwards,  the  distance  between  the  tubers  being 
twelve  to  fifteen  inches.  The  soil  is  then  raked  into  the  trenches. 
In  about  a  month  the  tops  of  the  stems  will  show  above  the 
surface,  and  so  soon  as  the  rows  can  be  clearly  seen  we  should 
hoe  between  them  so  as  to  preserve  the  soil  moisture  at  what 
is  usually  a  dry  period  of  the  year.  A  little  later,  when  the 


THE  CARROT  135 

stems  are  four  inches  above  ground,  the  rows  should  be  earthed 
up  with  the  draw  hoe.  The  object  of  the  earthing  up  is  to  keep 
the  rhizomes  in  the  dark.  Rhizomes  exposed  to  light  become 
ordinary  green  stems  and  do  not  produce  tubers.  The  earthing 
up  must  be  repeated  about  a  month  later.  The  chief  qualities 
required  in  a  good  variety  of  Potato  are  shallow  "  eyes,"  power 
of  resisting  disease,  good  flavour  and  appearance  when  cooked, 
and  good  keeping  properties.  The  main  crop  Potatoes  are  ready 
to  be  dug  up  when  the  aerial  stems  have  begun  to  die  down.  They 
are  dug  up  with  the  fork,  separated  into  three  portions,  according 
to  size,  namely,  for  cooking,  for  seed,  and  for  pig  feeding.  If 
any  disease  has  appeared  the  stems  should  be  dried  and  burnt. 

To  store  Potatoes,  they  are  piled  in  any  convenient  spot  on  a 
bed  of  straw,  and  are  also  covered  with  straw.  A  trench  is  then 
dug  out  all  round  the  pile,  and  the  earth  taken  from  it  is  used 
for  the  purpose  of  covering  the  straw.  The  thickness  of  this 
covering  depends  on  the  locality,  the  point  being  that,  as  frost 
destroys  the  Potato  for  cooking  purposes,  the  Potatoes  must  be 
adequately  protected  from  frost.  The  thickness  of  the  soil 
covering  must  therefore  not  be  less  than  three  inches.  It  may 
be  more. 

The  cultivation  of  the  Potato  lends  itself  to  a  variety  of 
simple,  interesting,  and  important  experimental  work.  It  is 
therefore  recommended  that  every  year  in  the  school  garden 
comparative  tests  should  be  made  :  (a)  of  new  varieties,  or  (6)  of 
various  kinds  and  amounts  of  manures,  or  (c)  of  sprouted  as  against 
unsprouted  seed,  or  (d)  of  differences  in  distances  and  depths  of 
planting,  or  (e)  different  sizes  of  "  seed "  and  cut  tubers  as 
compared  with  uncut  tubers. 

THE  CARROT  (Daucus  Carota) 

The  Carrot,  together  with  the  Parsnip,  Celery,  and  Parsley, 
belongs  to  the  natural  order  Umbelliferae.  The  Wild  Carrot  is  a 
roadside  plant  found  in  most  parts  of  the  country.  Generally  it 
is  an  annual,  but  occasionally  it  is  a  biennial,  storing  up  reserve 
material  in  the  form  of  starch  in  the  first  year,  and  utilising 
this  store  for  the  production  of  the  fruit  in  the  second  year.  By 


136  THE  BOOK  OF  NATURE  STUDY 

taking  advantage  of  this  occasional  habit,  and  by  sowing  the 
seed  of  late  flowering  plants  in  the  autumn,  Vilmorin  succeeded 
in  producing  a  biennial  strain  resembling  the  cultivated  varieties. 
The  fruit  of  the  Carrot  is  a  schizocarp,  the  ripe  carpels  of  which 
split  into  mericarps,  each  containing  one  seed.  It  is  the  meri- 
carps  which  are  sown  by  the  gardener.  The  edible  portion  of 
the  Carrot  is  the  large  conical  taproot,  made  up  of  the  hypocotyl 
and  the  primary  root.  At  its  lower  end  this  taproot  thins  out 
into  a  long  cordlike  portion,  which  extends  to  a  very  considerable 
distance  into  the  soil.  A  cross  section  of  the  taproot  shows  a  red 
rind  and  a  yellow  core.  The  rind  is  the  bast  and  cortex;  the 
core  is  the  wood.  The  cells  of  the  tissues  of  the  core  are  neither 
lignified  nor  fibrous  during  the  first  year,  except  in  the  case  of 
plants  which  have  reverted  to  the  ancestral  habit  by  "  running 
to  seed."  The  reserve  material  of  the  cultivated  plant  is  not 
starch  but  sugar,  and  this  is  stored  to  the  extent  of  4  to  8  per 
cent,  in  the  tissues  of  the  rind.  It  is  the  endeavour  of  seeds- 
men to  produce  strains  with  a  maximum  of  rind,  since  the  pro- 
portion of  sugar  is  dependent  on  the  proportion  of  rind. 

The  most  suitable  soil  for  the  growth  of  Carrots  is  a  rather 
light,  well  drained  loam.  The  presence  of  undecomposed  farm- 
yard manure  tends  to  the  production  of  forked  roots,  and  con- 
sequently, as  in  the  case  of  the  Potato,  it  is  the  preceding  crops 
which  should  be  well  manured.  Since  it  is  the  mericarps  which 
are  sown,  germination  is  slower  than  in  the  case  of  true  seeds. 
It  is  therefore  best  to  damp  the  mericarps  a  few  days  before 
sowing  so  as  to  soften  their  walls.  It  is  also  usual  to  mix  the 
"  seed  "  with  sand,  so  as  to  ensure  a  thin  distribution.  A  soil 
which  has  been  well  worked  for  the  preceding  crop  and  is  on  the 
light  side  will  require  only  to  be  dug  over  in  March.  From  the 
end  of  that  month,  and  successionally  if  desired,  in  April  and  May, 
the  seed  may  be  sown.  The  ground  having  been  first  trodden, 
not  too  heavily,  and  then  raked  over,  shallow  drills  are  made 
with  the  draw  hoe  one  inch  deep  and  one  foot  apart ;  after  sowing 
thinly  the  soil  is  lightly  raked  over  the  drills.  When  the  young 
plants  are  two  inches  high  they  should  be  thinned  out.  This 
thinning  may  be  so  conducted  that  at  first  the  plants  are  four 
inches  apart.  When  big  enough  to  be  used  for  soups  and  stews, 


THE  PARSNIP  137 

every  other  plant  may  be  drawn,  thus  leaving  eight  inches  be- 
tween those  plants  which  will  constitute  the  autumn  main  crop. 
Keep  the  Dutch  hoe  going  between  the  rows  during  the  hot  dry 
weather,  and  water  if  necessary.  The  main  crop  is  gathered  in 
the  latter  half  of  October,  the  fork  being  used  for  loosening  them 
in  the  ground,  so  as  to  avoid  snapping  the  roots  in  the  region  of 
thicker  growth.  They  should  be  stored  in  a  dry  place  in  ashes  or 
sand.  For  this  purpose  a  layer  of  sand  is  placed  on  the  ground 
in  a  corner  of  a  shed,  and  on  this  a  layer  of  roots  is  placed,  over 
this  layer  is  spread  another  layer  of  sand  an  inch  thick,  and  so 
on.  Among  the  best  varieties  are,  James'  Scarlet  Intermediate, 
Early  Nantes,  Early  Horn,  and  Veitch's  Model. 

For  experimental  work,  the  pupils  should  examine  the  flower, 
schizocarp,  and  mericarp.  They  should  compare  the  times  of 
germination  of  dry  and  damped  mericarps.  They  should  grow 
seedlings,  and  should  also  dig  up  young  plants  about  two  months 
old  and  observe  the  root  system.  They  should  also  examine  the 
taproot  of  a  second  year  plant  (or  of  a  plant  which  has  "  bolted  "), 
comparing  it  with  that  of  a  one-year-old  unbolted  plant. 


THE  PARSNIP  (Pastinaca  sativa) 

Much  of  what  has  been  said  about  the  Carrot  applies  also  to 
the  Parsnip.  Its  ancestor  is  a  common  roadside  annual  or  biennial 
plant  possessing  a  small  taproot.  Professor  Buckman,  of  the 
Cirencester  Royal  Agricultural  College,  was  able  by  cultivation 
and  selection  of  the  wild  variety,  extending  over  a  few  genera- 
tions, to  increase  the  size  of  the  taproot  and  to  fix  the  biennial 
character,  so  as  to  produce  the  "  Student,"  a  variety  quite  suitable 
for  garden  cultivation.  The  edible  portion  is  a  taproot  formed 
of  the  hypocotyl  and  main  root.  The  taproot  may  be  conical,  or 
short  and  bulbous.  It  contains  about  80  per  cent,  of  water, 
4  per  cent,  of  sugar,  and  3  per  cent,  of  starch.  The  percentage 
of  sugar  increases  slightly  through  the  growing  period  at  the 
expense  of  the  starch.  These  two  carbohydrates,  of  course,  con- 
stitute reserve  stores  on  which  the  plant  draws  during  its  second 
year  of  growth  for  the  increase  in  the  stem  and  the  production  of 
flower  and  fruit.  The  fruit  is  a  schizocarp,  the  mericarps  of 


138  THE  BOOK  OF  NATURE  STUDY 

which  constitute  the  "  seed."  Each  mericarp  contains  a  seed. 
The  essential  oil  contained  in  canals  in  the  fresh  mericarps  give 
the  seed  a  characteristic  smell  which  is  absent  from  two-year-old 
seed.  Parsnips  will  do  well  on  heavier  soil  than  is  suitable  for 
Carrots.  The  bed  should  be  manured  and  double  dug  in  autumn, 
and  left  rough.  Early  in  March  it  should  be  raked  down  and 
the  seed  sown  thinly  in  dry  weather  in  drills  made  with  the  draw 
hoe,  at  a  distance  of  fifteen  inches  apart,  so  as  to  give  sufficient 
room  for  the  leaves.  The  seed  is  then  covered  in  by  means  of 
the  rake.  When  the  young  plants  are  two  inches  high  they 
should  be  thinned  out  so  as  to  stand  nine  inches  apart.  Parsnips 
are  best  not  stored,  but  dug  up  as  required  for  household  use  in 
late  autumn  and  winter.  The  varieties  are  not  numerous,  and  of 
these  the  best  for  home  consumption  are  The  Student  and  Tender 
and  True. 

THE  BEET  (Beta  maritima) 

The  ancestor  of  this  vegetable  is  the  wild  perennial  Beet, 
which  is  found  abundantly  on  our  sea-coasts.  It  belongs  to  the 
natural  order  Chenopodiacese.  Under  cultivation  it  is  a  biennial. 
The  edible  portion  is  the  conical  or  napiform  hypocotyl  and 
main  root.  The  cell  sap  is  rich  in  sugar.  The  "  seeds "  are 
really  fruits,  each  containing  one  true  seed.  The  plant  being 
a  halophyte,  it  is  benefited  by  a  thin  manuring  with  common 
salt,  or  with  seaweed.  In  cookery  it  may  be  used  either  as  a 
vegetable,  a  salad,  or  a  pickle.  Like  the  Carrot,  it  tends  to  fork 
if  the  soil  contains  undecomposed  farmyard  manure.  The  bed 
should  be  double  dug  in  the  previous  autumn,  raked  down  at  the 
end  of  March,  and  the  seed  sown  from  April  to  June  if  a  succession 
is  desired,  but  the  main  sowing  should  be  made  at  the  beginning 
of  April.  Drills  are  made  with  the  draw  hoe  one  inch  deep,  and 
at  a  distance  apart  of  one  foot.  When  about  two  inches  high 
the  plants  should  be  thinned  out  to  a  distance  of  eight  inches, 
and  as  the  Beet  is  injuriously  affected  by  dryness  the  thinning 
should  be  effected  in  showery  weather.  For  the  same  reason 
the  surface  soil  should  be  kept  in  a  powdery  condition,  and  in 
very  dry  weather  water  or  liquid  manure  should  be  supplied. 
Salt  may  be  given  as  a  thin  top  dressing  during  showery  weather 


THE  TURNIP  139 

in  June  or  July.  The  roots  may  be  pulled  and  stored  at  the 
end  of  Ocotber,  and  special  care  should  be  taken  not  to  injure 
the  main  root,  which  "bleeds"  freely.  Special  attention  must 
be  devoted  to  storage  in  a  cool  place,  where  the  roots  will  not  be 
exposed  to  evaporation.  The  method  followed  is  the  same  as 
that  recommended  for  Carrots,  except  that  the  stored  roots 
must  be  protected  from  frost  by  a  good  covering  of  straw  or 
litter.  The  best  varieties  are  Dell's  Crimson,  Crimson  Ball, 
Button's  Globe,  and  Cheltenham  Green  Top. 


THE  TURNIP  (Brassica  Rapa) 

The  White  Turnip  of  the  garden  differs  from  the  agricultural 
Swede  Turnip  in  the  colour  of  its  flesh.  The  Garden  Turnip  also 
has  no  "  neck,"  and  its  leaves  are  grass  green  in  colour  as 
compared  with  the  glaucous  green  leaves  of  the  Swede.  The 
Turnip  is  a  biennial,  and  the  part  consumed  is  the  "bulb,"  which 
is  composed  of  the  primary  root  and  the  hypocotyl.  All  but 
the  outer  portion,  one-eighth  of  an  inch  in  thickness,  of  the 
bulb,  consists  of  wood,  composed  of  non-lignified,  thin-walled 
parenchyma.  The  bulb  contains  approximately  90  per  cent,  of 
water,  5  per  cent,  of  sugar,  0*5  per  cent,  of  proteid,  0*5  per  cent. 
of  fibre,  and  0*3  per  cent,  of  fat.  The  maximum  proportion  of 
sugar  and  of  proteid,  and  the  minimum  proportion  of  water, 
occur  when  the  bulb  has  reached  maturity.  After  germination  the 
cotyledons  of  the  seedling  plants  come  above  ground,  and,  like 
ordinary  foliage-leaves,  carry  on  the  work  of  assimilation.  It 
is  important  at  this  stage  to  hasten  the  development  of  the  hairy 
first  foliage-leaves,  since  the  smooth  seed-leaves  are  particularly 
susceptible  to  attack  by  the  Turnip  beetle.  This  acceleration  of 
growth  is  best  secured  by  dressing  the  bed  at  the  time  of  sowing 
with  a  thin  coat  of  superphosphate  of  lime. 

During  the  second  year  of  growth  the  very  short  stem 
bearing  the  rosette  of  first  year  leaves  elongates  considerably 
and  produces  the  inflorescence.  The  flowers  of  the  White  Turnip 
are  bright  yellow.  Those  of  the  Swede  are  pale  yellow.  The 
fruit  is  a  siliqua.  When  ripe  the  two  carpels  dehisce  upwards, 
exposing  the  seeds  which  are  borne  on  the  placenta  and  replum. 


140  THE  BOOK  OF  NATURE  STUDY 

The  Turnip  thrives  best  in  a  light  loamy  soil  and  in  a  moist 
season.  Drought  is  fatal,  and  hence  watering  must  be  carefully 
attended  to. 

For  a  succession  of  crops  the  seeds  may  be  sown  from  the 
beginning  of  March  to  the  end  of  July.  Manure  may  be  put  on 
before  sowing,  and  the  seed  bed  must  be  well  worked.  By  means 
of  the  draw  hoe  and  garden  line  shallow  drills  are  made,  not 
more  than  two  inches  deep,  and  at  a  distance  apart  of  one  foot. 
In  a  moist  season  germination  and  growth  are  rapid,  and  in  three 
weeks  from  sowing  the  rows  will  be  ready  for  thinning,  which 
in  the  case  of  small  beds  may  be  done  by  hand  picking,  or  in 
larger  quantities  by  means  of  the  hoe.  For  home  consumption, 
medium  sized  bulbs  are  better  than  large  ones,  and  hence  it  will 
be  sufficient  to  leave  a  space  of  eight  inches  between  the  plants. 

"  Cardinal "  is  a  good  early  variety,  while  "  All  the  Year 
Round"  is  satisfactory  for  main  crop  sowings.  Roots  maturing 
in  November  should  be  stored  in  sand  or  ashes  for  winter 
consumption. 

THE  RADISH  (Raphanus  sativus) 

Cultivation  of  this  crop  is  very  simple.  The  principal  thing 
is  to  ensure  rapid  growth  so  as  to  avoid  the  development  of  woody 
fibre  in  the  xylem  tissue,  which  constitutes  the  edible  portion. 
Hence  a  deep  mellow,  rich,  well  worked  seed  bed  is  necessary. 
Sowings  may  be  made  broadcast,  commencing  in  a  sheltered 
position  in  February,  and  continuing  through  the  summer  at 
intervals.  Thinning  can  be  effected  in  the  process,  of  pulling 
the  most  forward  roots  for  consumption,  i.e.  provided  the  seed 
was  thinly  sown. 

In  town  schools  where  garden  ground  is  not  available  the 
seeds  may  be  sown  in  boxes,  provided  that  good  soil  can  be 
procured  for  the  boxes,  and  that  the  soil  is  kept  fairly  moist. 

THE  ONION  (A  Ilium  Cepa) 

A  vertical  section  of  an  Onion  plant  shows  a  very  short  stem 
wrapped  over  with  thickened  scale-leaves.  It  is  therefore  a  bulb. 
Usually  the  plant  is  a  biennial,  but  occasionally  individual  plants 


THE  ONION  141 

live  for  more  than  two  years.  The  reserve  food  material  stored 
during  the  first  year  in  the  scale-leaves  is  utilised  in  the  second 
year  for  the  production  of  the  inflorescence.  The  pungent  smell 
of  the  Onion  is  due  to  the  presence  of  a  volatile  sulphur-containing 
oil. 

The  plant  requires  for  its  full  development  a  rich,  moist, 
fine  seed  bed.  The  bed  is  preferably  manured  and  ridged  up  in 
the  preceding  autumn.  The  ridges  are  levelled  down  in  March, 
and  the  ground  is  then  trodden  firm.  After  the  surface  has  been 
raked  fine  the  seed  is  sown  thinly  in  drills,  one  foot  apart  and 
one  inch  deep.  Give  a  dusting  of  soot,  if  this  can  be  readily 
procured,  and  then  rake  over  lightly.  The  rows  must  be  thinned 
until  the  young  plants  stand  singly  at  a  distance  of  six  or  eight 
inches  apart.  The  thinnings  may  be  consumed  as  salad.  If 
the  ground  is  very  dry  during  the  summer  it  should  be  watered.  It 
should  also  be  kept  as  free  from  weeds  as  possible.  Towards 
the  end  of  the  summer  the  leaves  begin  to  turn  yellow,  and  they 
should  then  be  trodden  over  carefully,  so  that  they  lie  horizontally. 
This  operation  assists  in  the  production  of  larger  bulbs,  and  at 
the  same  time  gives  full  play  to  the  ripening  effect  of  the  sun's 
rays.  In  September  the  bulbs  will  be  ready  to  be  taken  up. 
They  should  be  laid  out  to  dry  and  harden  in  the  sun,  and  when 
this  is  accomplished  they  may  be  tied  together  in  bunches  and 
hung  up  in  a  cool  dry  place  and  kept  free  from  frost.  Giant 
Rocca,  James'  Long  Keeping,  and  Bedfordshire  Champion  are 
good  varieties.  Ailsa  Craig  produces  exceptionally  large  bulbs, 
and  is  therefore  very  common  at  horticultural  shows.  Its  quality 
is,  however,  not  nearly  so  good  as  the  varieties  recommended. 

A  rather  different  culture  is  required  in  the  case  of  Tripoli 
Onions.  These  are  sown  in  drills  in  August,  and  are  transplanted 
in  March  for  spring  Onions. 

THE  LEEK  (Allium  porrum)  and  THE  SHALLOTT 
(A  Ilium  ascalonicum) 

are  closely  allied  to  the  Onion.  Leek  seed  may  be  sown  broad- 
cast and  very  thinly  on  a  nursery  bed  in  March.  When 
the  young  plants  are  about  four  inches  high  they  must  be 


142  THE  BOOK  OF  NATURE  STUDY 

transplanted  to  V-shaped  trenches,  eight  inches  deep  and  two 
feet  apart.  The  plants  should  be  one  foot  apart.  They  should 
be  lightly  watered  from  time  to  time,  and  when  firmly  rooted 
and  grown  sufficiently  to  appear  well  above  the  surface  of  the 
ground,  the  trenches  should  be  carefully  filled  in.  As  the  plants 
continue  to  grow  in  height  the  earth  should  be  ridged  round 
them.  The  object  of  this  treatment  is  obviously  similar  to  that 
adopted  in  the  case  of  Celery,  and  aims  at  the  production  of  well 
blanched  tender  bulbs.  Musselburgh  is  the  best  variety. 

The  Shallot  is  a  perennial.  Some  of  the  lateral  buds  produce 
shoots  which  form  small  buds,  and  a  bed  of  Shallots  therefore 
shows  a  series  of  groups  of  bulbs  arranged  circularly  round  the 
main  bulb.  It  is  these  smaller  bulbs  called  "  cloves  "  which  are 
usually  employed  for  "seed,"  though  the  Shallot  may  also,  of 
course,  be  propagated  from  true  seed.  The  "  cloves  "  are  planted 
in  drills  in  March,  the  drills  being  one  foot  apart  and  the  cloves 
at  six  inches  in  the  drills.  Gather  and  dry  in  September  as  in  the 
case  of  Onions. 

CELERY  (Apium  graveolens) 

In  order  that  the  stems  of  this  plant  may  be  fit  for  consumption 
it  is  essential  that  they  should  be  as  free  as  possible  from  woody 
fibre  and  be  well  blanched.  This  object  is  secured  by  planting  in 
trenches  and  subsequently  earthing  up  at  intervals  as  the  plants 
develop.  A  soil  rich  in  farmyard  manure  is  essential.  The 
seeds  are  sown  in  March  in  rich  soil  and  transplanted  to  the 
trenches  in  July,  at  a  distance  apart  of  nine  to  twelve  inches. 
The  trenches  are  prepared  by  taking  out  the  soil  to  a  depth  of 
fifteen  inches  by  fifteen  inches  in  width.  A  heavy  dressing  of 
well  rotted  manure  is  then  dug  into  the  bottom  of  the  trench 
and  thoroughly  mixed  with  the  soil.  On  the  top  of  this  is  spread 
some  of  the  soil  removed  from  the  trench  to  a  depth  of  about 
three  inches,  and  in  this  soil  the  young  plants  are  carefully  set. 
As  the  plants  grow  in  height  they  are  earthed  up  from  time  to 
time,  and  particular  attention  must  be  given  to  watering  at  the 
roots  ;  neither  water  nor  soil  should  be  allowed  to  get  between 
the  stems.  They  are  dug  up  as  required  during  the  winter.  A 
good  variety  is  Incomparable  White. 


PARSLEY,  SPINACH,  LETTUCE  143 

PARSLEY  (Carum  petroselinum) 

This  plant  belongs  to  the  same  order  as  Celery.  The  seed, 
which  takes  some  weeks  to  germinate,  may  be  sown  thinly  at  any 
time  from  April  to  July  in  drills  one  foot  apart.  The  plants  are 
thinned  to  a  distance  of  six  inches  apart.  A  small  proportion  of 
the  shoots  will  produce  flowers  and  seed  in  the  following  year, 
but  the  plant  may  be  regarded  for  practical  purposes  as  a  perennial, 
and  unless  the  climate  is  rigorous  may  be  allowed  to  stand  for 
at  least  two  seasons.  Parsley  grows  satisfactorily  in  almost  any 
moderately  good  garden  soil. 

SPINACH  (Spinacia  oleracea) 

This  plant,  belonging  to  the  Goosefoot  order,  is  cultivated 
for  its  leaves.  The  most  useful  variety  is  the  winter  or  prickly 
Spinach,  since  this  comes  into  use  at  a  time  of  the  year  when 
there  is  some  shortage  in  the  supply  of  a  variety  of  green  vege- 
tables. Cultivation  is  very  simple.  A  moist,  well  drained,  rich 
soil  is  required,  and  in  this  the  seed  should  be  sown  very  thinly 
in  August,  in  rows  fifteen  inches  apart.  The  plants  are  thinned 
to  a  distance  of  six  inches  apart,  and  if  the  weather  is  subsequently 
dry,  water  or  liquid  manure  should  be  given  at  the  roots  from 
time  to  time.  The  crop  will  be  ready  for  gathering  from  the 
beginning  of  November. 

THE  LETTUCE  (Lactuca  saliva) 

Small  patches  of  this  valuable  salad  plant  may  be  sown  from 
March  till  the  end  of  August  on  a  warm  moist  bed.  If  sown 
very  thinly  and  in  very  small  patches  it  is  not  necessary  to  trans- 
plant. It  will  be  sufficient  merely  to  pull  out  and  consume  the 
largest  plants  as  required.  Cultivation  on  a  larger  scale  involves 
transplanting  into  rows  one  foot  apart  with  a  distance  of  nine 
inches  between  the  plants.  If  desired  we  may,  instead  of  sowing 
in  patches,  sow  thinly  in  drills,  thinning  out  to  the  proper  distance. 
The  treatment  for  Cos  and  Cabbage  Lettuces  is  the  same,  with  the 
exception  that  the  plants  of  the  former  variety  must,  when  large 


i44  THE  BOOK  OF  NATURE  STUDY 

enough,  be   tied  round  with   string   or  bast,   so  as   to   prevent 
bolting,  and  to  blanch  the  inner  leaves. 


CRESS  (Lepidium  sativum) 

This  is  best  grown  in  boxes,  and  is  therefore  equally  as  suitable 
for  cultivation  in  town  as  in  country  schools.  Any  small  wooden 
box  may  be  used.  The  box  should  be  filled  with  a  mixture  of 
good  garden  soil  and  leaf-mould  pressed  firmly  down,  and  so 
that  its  surface  is  about  one  inch  from  the  top  of  the  box.  The 
seed  is  sown  thickly  on  the  surface,  a  little  soil  is  sprinkled  thinly 
over  them  and  gently  pressed  down.  The  box  is  then  covered 
over  with  paper  until  the  seedlings  begin  to  appear.  The  Cress 
will  be  ready  for  cutting  in  ten  days  or  a  fortnight  from  the  time 
of  sowing.  In  the  early  part  of  the  spring  the  Cress  boxes  should 
be  kept  in  the  schoolroom.  Later  they  may  stand  out  of  doors. 

BEANS  AND  PEAS 

These  plants  belong  to  the  natural  order  Leguminosae  and  the 
sub-order  Papilionaceae.  They  all  possess  the  power  of  assimilat- 
ing free  nitrogen  from  the  mixture  of  gases  present  in  the  soil 
spaces.  This  they  do  through  the  agency  of  the  Bacterium 
radicicola  with  which  they  have  a  symbiotic  relationship.  If 
one  of  these  plants  is  carefully  dug  up  by  the  roots  and  well 
washed  until  free  from  soil  particles  there  will  be  seen  on  the 
roots  numerous  small  round  pink  or  white  bodies  varying  in  size 
from  a  pin's  head  to  a  small  pea.  These  are  the  nodules.  A 
cross  section  of  a  nodule  when  mounted  or  viewed  under  the 
microscope  shows  a  central  mass  of  parenchymatous  cells  packed 
with  rod-shaped  and  Y-shaped  bacteria.  When  the  plant  gets 
old  the  nodules  become  disintegrated,  and  the  bacteria  become  free 
in  the  soil.  When  new  plants  are  grown  in  the  soil  the  bacteria 
make  their  way  through  the  root  epidermis  and  again  give  rise 
to  the  nodular  excrescences.  Thus  in  a  soil  rich  in  this  species 
of  bacterium,  leguminous  plants  are  independent  of  the  nitrates 
present  in  the  soil;  and  further,  owing  to  the  accumulation  of 
nitrogenous  compounds  in  the  roots,  such  plants  may  leave  a 


2  I 


I  I 

r^  C 


BEANS  AND  PEAS  145 

soil  richer  in  nitrogen  after  the  crop  is  gathered  than  before  it 
was  planted.  It  is  for  this  reason  that  wheat,  which  requires 
an  abundant  supply  of  nitrogen,  does  best  as  a  rule  when  it  follows 
a  clover  crop.  During  the  past  few  years  numerous  experiments 
have  been  made  in  seeding  with  Bacterium  radicicola  soils  which 
were  poor  in  nitrogen  and  poor  in  this  particular  micro-organism. 
Various  preparations  of  soil  containing  the  bacteria  in  abundance 
have  been  put  on  the  market  under  the  name  of  Nitragin,  Nitro- 
bacterine,  etc.  In  a  number  of  cases  in  this  country  and  in 
America  it  is  stated  that  increased  crops  have  resulted  from  the 
dressing.  The  careful  experiments  on  Peas  carried  out  by  Chitten- 
den  at  the  Royal  Horticultural  Society's  Experimental  Gardens 
at  Wisley  seem  to  show,  however,  that  the  inoculation  of  legum- 
inous crops  with  Nitrobacterine  in  ordinary  garden  soil  is  not 
likely  to  prove  beneficial.1 

Beans  and  Peas,  regarded  from  the  point  of  view  of  food,  are 
remarkable  for  their  high  nitrogenous  contents.  They  contain 
14  per  cent,  only  of  water,  50  per  cent,  of  carbohydrates  (starch 
and  sugar),  and  over  20  per  cent,  of  proteid.  They  also  contain 
considerable  quantities  of  salts  of  potassium  and  calcium.  Peas 
and  Beans  thus  contain  a  bigger  proportion  of  food  material  than 
any  other  vegetable,  and  for  persons  of  robust  digestive  powers 
approach  meat  in  their  value  as  suppliers  of  nitrogen. 


THE  DWARF  FRENCH  OR  KIDNEY  BEAN  (Phaseolus  vulgaris) 

This,  like  the  Scarlet  Runner,  is  much  less  hardy  than  the 
Broad  Bean  or  Pea,  and  it  is  therefore  not  safe  to  sow  the  seeds 
earlier  than  the  last  week  in  April.  Even  at  that  date  the  bed 
should  be  in  a  sheltered  and  sunny  position.  The  soil,  which 
must  be  good,  should  have  been  manured  in  the  preceding  autumn, 
as  this  plant  does  not  thrive  in  soil  containing  undecomposed 
farmyard  manure.  For  sowing  the  seeds,  make  a  shallow  drill 
with  the  draw  hoe  one  and  a  half  inch  deep,  drop  two  or  three 
seeds  at  intervals  of  six  inches,  and  leave  one  and  a  half  foot 
between  the  rows.  If,  when  the  young  plants  show  above  ground, 

1  See  "  Contributions  from  the  Wisley  Laboratory,  No.  IV.     The  Inoculation  of 
Leguminous  Crops,"  Journ.  of  the  Roy.  Hort.  Soc.  1908. 
VOL.  v. — 10 


146  THE  BOOK  OF  NATURE  STUDY 

the  weather  is  very  dry,  they  will  be  benefited  by  a  good  watering. 
It  is  important  that  throughout  growth  the  soil  should  be  kept 
moist,  and  this  can  best  be  secured  by  maintaining  a  good  surface 
mulch  of  loose  soil  with  the  hoe. 


THE  SCARLET  RUNNER  (Phaseolus  multiflorus) 

The  time  and  method  of  planting  are  much  the  same  as  in  the 
case  of  the  Dwarf  Bean,  except  that  the  seeds  are  sown  in  a  double 
row  in  a  drill  ten  to  twelve  inches  wide.  The  plants  will  grow 
to  a  height  of  six  or  seven  feet.  When  the  plants  are  three 
inches  above  ground  they  must  be  staked  with  stout  poles 
seven  feet  high.  Like  the  Dwarf  Bean,  the  plants  require  an 
abundance  of  moisture,  and  they  should  therefore  be  mulched 
with  manure  or  by  hoeing. 


THE  BROAD  BEAN  (Vicia  Faba) 

This  is  a  very  hardy  plant,  which  will  succeed  on  almost  any 
soil,  though  it  is  most  productive  on  a  stiffish  clay.  It  is  better 
to  plant  in  rows  rather  than,  as  is  usually  done,  in  plots.  The 
seeds  are  sown,  at  the  end  of  February  or  the  beginning  of  March, 
in  drills  ten  inches  wide  and  three  inches  deep  made  with  the  draw 
hoe.  A  double  row  is  sown  on  either  side  of  the  drill,  the  distance 
between  each  seed  being  about  six  or  eight  inches.  As  soon  as 
the  flowers  drop  off  and  the  pods  begin  to  form  the  tip  of  each 
plant  is  pinched  off.  This  procedure  is  found  to  result  in  the 
production  of  better  filled  pods. 

THE  PEA  (Pisum  sativum) 

The  Pea  thrives  best  in  a  deep  rich  soil,  and  requires  abundance 
of  light  and  air.  Hence  the  soil  should  be  trenched  and  well 
manured  before  planting,  and  the  rows  should  run  north  and 
south,  and  should  not  be  close  together  or  overshadowed  with  other 
tall-growing  crops.  Peas  are  hardy  like  the  Broad  Bean,  and  the 
main  crop  sowing  may  be  made  at  the  beginning  of  March. 
Successional  sowings  may  be  made  in  April  and  May.  A  shallow 


THE  PEA  147 

trench  eight  inches  wide  and  two  inches  deep  is  made  with  the 
draw  hoe,  and  over  this  the  seeds  are  sprinkled  thinly  at  the 
rate  of  one  pint  of  Peas  to  every  ten  yards  of  the  drill.  Peas 
suffer  very  much  from  the  depredations  of  mice  and  birds,  and  to 
protect  them  from  these  it  is  well  to  moisten  the  seeds  with  water 
and  then  to  dust  them  with  red  lead  just  before  sowing.  After 
the  soil  has  been  raked  over  the  drills,  black  thread,  to  which  white 
feathers  have  been  tied,  should  be  stretched  over  the  drills  with 
the  object  of  scaring  the  birds.  Or,  instead,  pieces  of  fine  wire 
netting  fourteen  inches  wide  and  three  feet  long  may  be  bent  into 
the  form  of  an  arch  and  laid  over  the  drills.  As  soon  as  the  young 
plants  are  two  to  three  inches  high,  the  rows  should  be  earthed  up 
on  either  side.  Dwarf  varieties,  such  as  American  Wonder,  will 
not  require  further  treatment,  but  the  tall  maincrop  kinds,  such 
as  Telephone,  Telegraph,  Marrowfat,  Autocrat,  and  Early  Giant, 
will  require  to  be  carefully  staked  with  trimmed  branches  of 
larch  or  fir,  four  to  five  feet  high. 


CHAPTER  X 
FRUIT  CULTURE 

BOTANISTS  define  a  fruit  as  consisting  of  the  ovary  and  whatever 
other  parts  of  the  flower  persist  at  the  time  the  seed  is  ripe.  A 
number  of  plants,  however,  such,  for  example  as  the  Tomato, 
Cucumber,  Vegetable  Marrow,  Peas,  and  Beans,  are  classed  by 
horticulturists  as  vegetables,  although  the  edible  portion  com- 
plies with  this  definition.  Horticulturally,  only  those  fruits 
which  are  juicy  and  contain  considerable  quantities  of  sugars  and 
organic  acids  (malic,  citric,  and  tartaric)  are  regarded  as  coming 
under  this  category.  The  common  hardy  fruits  of  the  British 
Isles  include  Apples,  Pears,  Plums,  Damsons,  Cherries,  Medlars, 
Gooseberries,  Currants,  Raspberries,  Strawberries,  Blackberries, 
Loganberries  ;  and  it  is  noteworthy  that,  excepting  Medlars,  Goose- 
berries, and  Currants,  all  these  fruits  are  members  of  the  great 
natural  order,  Rosaceae,  characterised  by  the  regular  perigynous 
flower,  the  gamosepalous  five-sepalled  calyx,  the  polypetalous 
five-petalled  corolla,  the  many  stamened  androecium,  and  the 
apocarpous  gynoecium.  Among  the  less  hardy  fruits  which 
nevertheless  in  some  parts  of  the  country  may  be  satisfactorily 
grown  out  of  doors  in  sheltered  positions,  are  the  Fig,  Grape, 
Nectarine,  Peach,  and  Apricot. 

Of  the  fruits  above  mentioned  the  following  only  are  generally 
suitable  for  cultivation  in  a  school  garden  : — 

The  Apple  (Pyrus  Malus),  the  Pear  (Pyrus  communis),  the 
Plum  (Prunus  domestica),  the  Cherry  (Prunus  Cerasus),  the  Goose- 
berry (Ribes  Grossularia)  the  Currant  (Ribes  rubrum  and  Ribes 
nigrum),  and  the  Strawberry  (Fragaria  vesca).  It  is  suggested, 
however,  that  in  school  gardens,  where  there  are  facilities  for  the 
training  of  Blackberries  along  wire  fences,  some  experimental 
work  might  be  carried  on  in  the  direction  of  the  domestication 

and  improvement  of  this  fruit.     It  would  appear  that  there  is 

148 


FRUIT  CULTURE  149 

considerable  scope  for  cultivation  of  the  Blackberry,  and  it  would 
be  interesting  work  to  study  the  effect  of  cultivation,  pruning, 
and  manuring  on  some  of  the  thirty-four  species  or  sub-species 
of  Rubus  fruticosus  described  in  the  British  Flora.  (Consult 
Bentham  and  Hooker,  British  Flora.) 

It  is  to  be  hoped  that  in  course  of  time  a  portion  of  every 
school  garden  will  be  devoted  to  fruit  culture.  The  fact  that 
the  hardy  British  fruits  can  be  profitably  grown  in  perfection 
in  this  country  with  ordinary  attention  and  skill,  considered  in 
connection  with  the  further  fact  that  between  four  and  five 
million  of  bushels  of  apples  alone  are  yearly  imported  into  this 
country,  point  to  the  desirability  of  the  further  increase  in  the 
area  devoted  to  fruit  culture.  According  to  the  returns  of  the 
Board  of  Agriculture,  the  total  area  of  land  under  cultivation  in 
Great  Britain  is  about  fifty-six  million  acres,  of  which  about  a 
quarter  of  a  million  acres  are  orchards  and  one  hundred  thousand 
acres  are  under  small  fruit  (Currants,  Gooseberries,  and  Straw- 
berries). The  greatest  amount  of  orchard  ground  is  found  in  the 
counties  of  Worcester,  Hereford,  Gloucester,  Somerset,  Devon, 
and  Kent,  but  it  must  be  remembered  that  all  but  the  last  named 
are  mainly  cider-producing  counties.  In  small  fruit  Kent  easily 
heads  the  list  with  some  twenty-two  thousand  acres.  Next 
come  Worcestershire,  Herefordshire,  Hants,  Cambridge,  Norfolk, 
Essex,  Middlesex,  and  Surrey.  There  can  be  no  doubt  that 
while  the  soil  of  some  of  these  counties,  such  as  Hereford,  Wor- 
cester, Somerset,  Devon,  and  Gloucester,  are  especially  suitable 
for  Apple  culture,  there  is  no  county  in  which  the  area  under 
fruit  culture  could  not  be  profitably  increased.1  There  appears 
to  be  a  considerable  need  for  soil  surveys  in  each  county  for  the 
purpose  of  ascertaining  what  soils  and  formations  are  specially 
suitable  for  the  cultivation  of  various  fruits. 

In  deciding  what  varieties  to  plant  of  a  particular  fruit,  it 
is  desirable  to  ascertain  from  other  growers  in  the  neighbourhood 
and  from  local  nurserymen  what  kinds  have  been  found  to  succeed 
best  in  the  locality.  As  in  the  case  of  the  numerous  varieties 
of  potatoes,  differences  of  soil,  situation,  and  climate  have  a 

1  Consult  the  Journal  of  the  Roy.  Hort.  Soc.,  vol.  xxx.,  1906;  also,  "The  Report  of 
the  Departmental  Committee  upon  the  Fruit  Industry  of  Great  Britain."     (Cd.  2589). 


150  THE  BOOK  OF  NATURE  STUDY 

remarkable  effect  on  the  quality  and  even  appearance  of  the 
fruit.  Subject  to  this,  the  following  lists  supply  information 
respecting  the  best  varieties  of  fruits  possessing  the  essential 
characteristics  of  quality,  fertility,  good  growth,  and  hardiness. 
The  varieties  are  arranged  in  the  order  in  which  they  become 
ready  for  use. 

APPLES  FOR  COOKING 

Early  White  Transparent  .  .  August 

Lord  Grosvenor  .  .  .  September 

Pott's  Seedling  .  .  .  September 

Stirling  Castle  .  .  .  October 

New  Hawthornden      .  .  .  November 

Warner's  King  .  .  .  October  to  December 

Beauty  of  Kent  .  .  .  November  to  January 

Bismarck         ....  December  and  January 

Bramley's  Seedling      .  .  .  December  to  March 

Prince  Albert  .  .  .  January  and  February 

Newton  Wonder          .  .  .  February  and  March 

DESSERT  APPLES 

Mr.  Gladstone  .  .  .  August 

Irish  Peach      ....  August 

Devonshire  Quarrenden  .  .  September 

Worcester  Pearmain    .  .  .  September 

James  Grieve  ....  October 

Cox's  Orange  Pippin    .  .  November  to  January 

Lord  Hindlip  ....  January  to  April 

All  the  above  Apples  may  be  grown  as  bushes  on  the  Paradise  stock,  or  as 
half-standards  on  the  Crab  stock. 

PEARS  FOR  COOKING 

Pitmaston  Duchess      .  .  .     October  and  November 

Catillac  ....     January  and  February 

DESSERT  PEARS 

William's  Bon  Chretien            .  .  September 
Louise  Bonne  de  Jersey        .  .  October 
Doyenne  du  Cornice  (in  shel- 
tered positions)         .             .  .  October  and  November 
Emile  d'Heyst              .             .  .  November 


FRUIT  CULTURE  151 

PLUMS  FOR  COOKING 

The  Czar          ....     August 

Victoria  .  .  .     August  and  September 

Pond's  Seedling  .  .  .     September 

DESSERT  PLUMS 

Early  Transparent  Gage        .  .  September 

Count  Althann's  Gage              .  .  September 

Bryanston  Gage           .            .  .  September 
Coe's Golden  Drop  (in  sheltered 

positions)     .            .            .  .  September 

CHERRIES  FOR  COOKING 
The  Kentish  The  Morello 

DESSERT  CHERRIES 
Early  Rivers  May  Duke  Black  Eagle 

RASPBERRIES 
Superlative  Hornet  Baumforth's  Seedling 

CURRANTS 

White  Dutch  (white) 
Raby  Castle  (red) 

Lee's  Prolific  (black)  .  .         On  light  soils 

Boskoop  Giant  (black)  .        Stated   by   some   Growers   to   be   less 

subject    to    attack    by    the    Black 
Currant  mite 

GOOSEBERRIES  FOR  COOKING 
Crown  Bob  Keepsake  Whinham's  Industry 

GOOSEBERRIES  FOR  DESSERT 

Yellow  Champagne  Red  Champagne 

Warrington  Whitesmith 

STRAWBERRIES 

Royal  Sovereign          .  .        Early 

President         .  .  .        Midseason 

Black  Prince    .  .  .        Midseason.     Small  but  best  for  flavour. 

Givon's  Late  Prolific  .  .        Late 

Sir  Joseph  Pax  ton       .  .        Midseason.    The  chief  market  variety, 

but  not  so  good  in  flavour 


152  THE  BOOK  OF  NATURE  STUDY 

The  following  general  notes  on  planting  apply  for  the  most 
part  to  all  the  bush  and  tree  fruits  mentioned  above.  They 
indicate  the  present  practice  as  followed  by  the  most  experienced 
growers.  Readers  should,  however,  consult  the  reports  issued 
from  the  Woburn  Experimental  Fruit  Station  under  the  super- 
vision of  the  Duke  of  Bedford  and  Mr.  Spencer  Pickering.  Their 
results  are  not  in  harmony  with  the  common  practice  as  regards 
planting,  and  go  to  show  that  a  method  of  planting  which 
seriously  checks  the  tree's  root  system  may  give  a  better  result 
as  regards  fruit  production.  Further  experiments  in  methods  of 
planting  in  a  variety  of  soils  and  climates  are  required,  and  such 
experiments  are  very  suitable  for  inclusion  in  a  course  of  evening 
school  gardening. 

NOTES  ON  PLANTING 

(i)  Bushes  and  trees  should  be  planted  when  in  the  resting 
stage,  and  preferably  in  October  and  November. 

(ii)  Do  not  expose  the  roots  to  evaporation  in  the  air. 

(iii)  Cut  off  with  a  clean  cut  all  torn  roots,  and  also  cut  off  all 
large  roots  which  tend  to  grow  vertically  downwards. 

(iv)  In  preparing  the  hole  in  which  the  tree  is  to  be  planted 
see  that  it  has  a  diameter  at  least  one  foot  longer  than  the 
diameter  of  the  mass  of  roots. 

(v)  Dig  out  the  hole  to  a  depth  varying  with  the  kind  of  tree 
or  bush  to  be  planted,  but  such  that,  when  covered  in  the  tree, 
will  be  at  the  same  depth  in  the  soil  as  when  it  was  taken  up  by 
the  nurseryman.  This  will  generally  mean  a  depth  of  about  one 
foot.  Having  removed  the  soil  to  this  depth,  dig  over  the  under 
soil  so  as  to  provide  a  well  broken  substratum ;  over  this  spread 
a  little  of  the  top  soil. 

(vi)  Place  the  tree  in  position,  spread  out  the  roots  so  that 
they  may  occupy  their  natural  position,  and  carefully  crumble 
over  them  some  more  soil,  taking  care  that  it  is  worked  in  between 
the  roots  and  is  in  close  contact  with  them.  Shovel  in  a  little 
more  soil  so  as  to  cover  them  and  tread  it  down  lightly.  Fill 
in  the  remainder  of  the  soil  and  again  tread  it  down,  but  not 
hard.  There  should  be  no  farmyard  manure  or  pieces  of  turf  in 
contact  with  the  roots  of  the  newly  planted  tree.  When  all  the 


THE    APPLE  153 

soil  has  been  filled  in  it  should  be  two  or  three  inches  above  the 
ground  level,  so  as  to  avoid  the  formation  of  a  pit  as  it  subsides. 

(vii)  Water  well,  unless  the  soil  is  naturally  well  supplied 
with  moisture. 

(viii)  Drive  a  stout  stake  firmly  into  the  ground  close  to  the 
tree,  and  tie  the  tree  to  it  with  tarred  string.  This  will  support 
the  tree  against  the  autumn  and  winter  gales.  The  string  should 
be  examined  from  time  to  time  to  make  sure  that  it  is  not  chafing 
the  bark. 

(ix)  If  there  are  any  rabbits  within  reach  they  are  almost 
certain  to  nibble  the  bark  of  the  tree  in  hard  weather.  It  is 
therefore  important  in  such  a  case  to  protect  the  tree  with  wire 
netting.  This  can  only  be  done  effectively  by  surrounding  the 
tree  or  the  plantation  with  narrow  meshed  wire  netting  four 
feet  high,  sunk  into  the  ground  to  a  depth  of  six  inches,  and  having 
another  six  inches  underground  bent  at  right  angles  to  the  plane 
of  the  main  piece  and  pointing  away  from  the  tree.  If  this 
precaution  is  not  taken  the  rabbits  may  burrow  an  entrance 
under  the  netting. 

(x)  Keep  down  all  weeds  round  the  young  trees,  and  maintain 
a  surface  mulch  with  the  hoe,  so  as  to  prevent  evaporation  of 
moisture. 

THE  APPLE 

The  Apple  is  an  improved  form  of  the  Wild  Crab  which  is 
found  growing  in  hedgerowrs  in  all  parts  of  Great  Britain.  On 
account  of  its  productivity  and  high  content  (12  to  15  per  cent.) 
of  sugar,  starch,  and  organic  acids  it  is  the  most  valuable  of 
the  British  fruits.  Although  it  may  be  profitably  grown  on 
almost  any  soil,  except  a  very  shallow  topsoil  resting  on  gravel 
or  chalk,  it  thrives  on  a  somewhat  heavy  loam,  and  there  is 
reason,  moreover,  to  suppose  that  such  a  soil,  containing  a  relatively 
high  percentage  of  ferric  oxide,  is,  ceteris  paribtis,  the  best  of  all. 

New  varieties  of  Apples  are  obtained  by  cross  fertilisation 
of  existing  varieties  and  subsequent  sowing  of  the  pips  of  the 
resulting  fruits.  Owing  to  the  effects  of  reversion,  however,  not 
more  than  one  in  a  thousand  of  the  seedlings  will  produce  fruit 
even  passably  good  in  flavour  and  quality.  Multiplication  of 


154  THE  BOOK  OF  NATURE  STUDY 

trees  may  be  effected  by  grafting, — that  is  to  say,  by  the  insertion 
on  the  stem  of  a  portion  of  a  shoot  possessing  a  number  of  buds. 
The  stem  is  called  the  stock,  and  the  inserted  shoot  the  scion. 
When  the  operation  is  properly  carried  out  scion  and  stock 
become  organically  connected  through  the  union  and  subsequent 
development  of  the  cambial  tissues.  The  stock,  through  which 
water  and  mineral  substances  are  supplied  to  the  scion,  to  that 
extent  exercises  an  influence  on  the  latter,  so  that  we  speak  of 
strong  and  weak  stocks  ;  very  rarely  the  scion  assumes  some 
of  the  morphological  characters  of  the  stock,  but  generally 
speaking  stock  and  scion  retain  their  individual  characteristics. 
Three  kinds  of  stocks  are  available  for  use,  namely,  the  Crab, 
the  Paradise,  and  the  "  Free  stock."  The  Crab  is  a  strong, 
somewhat  deeply  rooting,  hardy  tree,  and  is  used  if  standard 
trees  are  required, — that  is  to  say,  tall  trees  with  a  clean  stem  up 
to  a  height  of  five  feet.  Standard  apple  trees  on  the  Crab  stock 
come  into  bearing  some  ten  years  from  the  time  of  grafting,  and 
remain  productive  for  from  forty  to  seventy  years.  The  Paradise 
stock  is  believed  to  be  an  Asiatic  variety  of  the  wild  apple.  It 
is  dwarf  in  habit,  has  a  short  tap  root  and  numerous  fibrous 
surface  feeding  rootlets.  Apple  trees  on  this  stock  are  dwarf 
(10  feet  high),  come  into  bearing  four  years  from  the  time  of 
grafting,  and  remain  productive  for  from  twenty  to  twenty-five 
years.  For  these  reasons  orchards  of  trees  on  the  Paradise  are  now 
much  more  frequently  planted  than  those  on  the  Crab  stock.  Free 
stocks  result  from  sowing  the  pips  of  varieties  of  cultivated  apples. 
They  are  sown  in  drills  in  the  autumn ;  when  two  years  old  the 
seedling  trees  are  transplanted  into  good  soil  at  a  distance  apart 
of  two  feet  all  round.  They  may  be  grafted  in  the  succeeding 
year.  Trees  on  such  stocks,  while  possessing  fibrous  surface 
feeding  roots,  are  intermediate  as  regards  size,  vigour,  and 
longevity  between  the  Paradise  and  the  Crab.  One  or  two  such 
seedling  trees  should  be  grown  in  the  school  garden.  There 
are  various  slightly  differing  methods  of  grafting,  namely,  whip 
and  tongue  grafting,  saddle  grafting,  and  crown  grafting.  The 
principle,  is  however,  the  same  in  all,  and  depends  upon  the  close 
juxtaposition  of  the  cambial  layers  of  stock  and  scion  with 
protection  from  the  atmosphere.  The  most  suitable  method 


THE   APPLE  155 

for  school  gardens  is  that  of  whip  and  tongue,  and  the  procedure 
is  as  follows. 

For  the  stock  we  may  select  either  the  Crab,  the  Paradise,  or 
the  Free  stock.  Crabs  may  be  found  in  the  hedges.  Paradise 
stocks  may  be  bought  from  nurserymen  at  about  thirty  shillings 
per  thousand,  or  ninepence  the  dozen.  Free  stocks  may 
be  raised  from  seed  as  described  above.  The  young  stocks 
should  be  planted  in  autumn  at  such  a  distance  apart  (say  two 
feet)  as  will  permit  the  grafting  operations  to  be  conveniently 
carried  out.  The  scions  are  obtained  by  cutting  off  from  the 
cultivated  trees  of  the  varieties  which  it  is  desired  to  propagate 
unbranched  shoots  eighteen  inches  in  length.  These  are  taken 
off  in  November  or  December,  tied  in  bunches,  and  the  cut  ends 
buried  in  the  soil  to  a  depth  of  three  or  four  inches.  About  the 
end  of  March1  the  stocks  will  show  by  the  swelling  of  the  buds 
that  the  spring  awakening  is  at  hand,  and  that  the  time  for  grafting 
is  ripe.  The  scions  are  taken  up,  and  with  a  sharp  knife  a  clean 
oblique  cut  is  made  across  each  one,  exposing  an  elliptical  surface 
two  inches  in  its  longer  diameter.  A  surface  corresponding  in 
size  is  similarly  exposed  by  cutting  the  stock  at  a  height  from  the 
ground  of  about  six  inches.  Next,  two  vertical  slits  are  made  on 
the  stock  and  on  the  scion  respectively  in  such  a  way  that  one 
tongue  on  each  fits  into  the  slit  in  the  other.  The  scion  is  then 
dovetailed  on  to  the  stock,  the  whole  carefully  bound  round 
with  bast,  and  the  bast  covered  with  grafting  wax  to  exclude  air 
and  moisture  (see  Fig.  59).  If  the  operation  has  been  successful 
the  buds  of  the  scion  will  open  and  produce  shoots  in  the  normal 
way,  and  the  bast  may  then  be  removed.  The  young  grafted 
trees  may  be  transplanted  into  their  permanent  quarters  in  the 
November  next  but  one  following.  Before  actually  trying  their 
hand  at  grafting  an  apple  tree  (and  the  same  applies  to  budding), 
beginners  should  practise  the  operation  on  small  pieces  of  green 
twigs  of  any  kind. 

Crown  grafting  (see  Fig.  58)  is  a  variety  of  grafting  practised 
where  the  diameter  of  the  stock  is  considerably  greater  than  that 

1  It  is  probable  that  grafting  might  with  advantage  be  deferred  till  rather  later. 
Some  men  of  great  practical  experience  hold  that  if  the  operation  is  carried  out  towards 
the  end  of  April  there  are  fewer  failures,  and  more  vigorous  trees  are  obtained. 


156 


THE  BOOK  OF  NATURE  STUDY 


FIG.  5S.-Crown  Grafting. 


of  the  scion.     It  is  a  method  specially  applicable  in  the  renova- 
tion of  old  standard  trees  of  poor  varieties.     Two  or  three  stout 

branches  (say  two  inches  in  diameter)  of  the 
stock  are  severed  with  a  slightly  oblique 
cut.  On  each  of  the  stumps  longitudinal 
incisions  two  inches  in  length  are  made 
in  the  bark.  The  bark  is  then  opened  by 
means  of  the  handle  of  the  budding  knife 
along  one  side  only  of  the  incision.  This 
will  serve  to  grip  the  scion  and  hold  it  in 
position.  The  other  side  is  left  untouched, 
and  the  scion  must  be  so  shaped  that  one 
portion  of  its  bark  and  cambial  layer  fits 

aS   dOSely   aS   POSsible   aSainst    the    PerPen- 

dicular  undisturbed  edge  of  the  incision. 
The  scions  having  been  inserted,  the  whole  is  bound  round  with 
bast  and  covered  with  grafting  wax.  . 

Where  considerable  numbers  of  young  trees  of  a  particular 
variety  are  required  there  may  be  a  difficulty  in  obtaining  the 
requisite  number  of  scions  for  grafting.  In  such  cases  it  is  more 
economical  and  just  as  effective  to  bud  the  trees  instead  of 
grafting  them.  Apples,  Pears,  Cherries,  Plums,  and  Roses  may 
be  propagated  readily  by  this 
method.  The  operation  is  car- 
ried out  at  the  end  of  July.  A 
T-shaped  incision  (see  Fig.  60) 
is  made  in  the  bark  of  the  stock 
and  the  bark  slightly  opened 
with  the  handle  of  the  budding 
knife  to  admit  the  bud.  The 
bud,  which  must  be  a  vegeta- 
tive one,  is  taken  from  about 
the  middle  of  a  shoot  of  the 
current  year.  To  cut  out  this 
bud,  an  oval  incision  is  made  in 
the  bark  which  surrounds  it, 
and  then  by  means  of  a  scooping  cut  the  bud,  bark,  and  a  small 
portion  of  the  underlying  wood  are  cut  out.  The  whole  length 


FIG.  59.— Whip  and  Tongue  Grafting. 


THE  APPLE 


157 


T 


of  the  excised  portion  should  not  exceed  one  inch.  The  small 
piece  of  adhering  wood  is  then  carefully  picked  out  without 
disturbing  the  bud  itself,  and  the  bud  is  inserted  under  the 
bark  at  the  T-shaped  cut,  and  bound  round  with  bast.  If  the 
operation  has  been  successful,  union  of  the  tissues  takes  place 
rapidly,  and  the  bast  may  be  removed  at  the  end  of  three  weeks' 
time. 

General  rules  for  the  planting  of  apple  trees  have  already 
been  given.  Where  a  number  of  trees  are  to  be  planted  it  is 
important  to  give  sufficient  space  for  the  admission  of  light  and 
air,  taking  care  at  the  same  time  that  there  is  no  waste  of  ground. 
The  trees  should  be  planted  in  rows  running  north  and  south. 
Standard  trees  must  be  at  a  distance  of  twenty  feet  apart,  dwarf 
trees  at  a  distance  of  eight 
feet.  As  the  standard  trees 
will  not  come  into  bearing 
for  some  years,  the  ground 
between  them  may  be  occu- 
pied by  Currant  and  Goose- 
berry bushes.  It  is  best 
that  the  orchard  ground 
should  be  kept  quite  free 
from  grass  and  weeds.  In 
this  way  only  can  the  trees  be  fed  with  manure  and  a  surface 
mulch  maintained  with  the  hoe.  If,  however,  some  of  the  ground 
must  be  under  grass,  at  least  a  circular  space  eight  feet  in 
diameter  must  be  kept  bare  round  each  tree.  If  grass  is  allowed 
to  grow  close  to  the  stem  of  newly  planted  trees,  the  demands 
which  it  makes  on  the  moisture  and  mineral  matter  of  the  soil 
will  cause  serious  permanent  injury  to  the  trees.  In  cultivating 
the  ground  around  fruit  trees  it  should  be  borne  in  mind  that  the 
tree  is  largely  fed  from  the  soil  through  its  fibrous  surface  roots, 
and  that  any  operation  which  injures  these  will  affect  the  fruitful- 
ness  of  the  tree.  Hence  the  cultivation  must  be  shallow.  On 
light  open  soils  the  Dutch  hoe  may  be  used  for  keeping  the  surface 
free  from  weeds  and  in  a  loose  condition.  On  heavier  soils  the 
fork  or  spade  must  be  used,  but  the  soil  should  not  be  disturbed 
to  a  greater  depth  than  two  to  three  inches. 


FlG.  60.— Budding.  A,  Incision  ;  B,  bud  ; 
C,  bud  inserted  ;  D,  Bud  fastened  in  and 
bound  with  bast. 


158  THE  BOOK  OF  NATURE  STUDY 

Very  little  experimental  work  has  been  carried  out  on  the 
effect  of  the  manuring  of  fruit  trees.  It  appears  probable,  how- 
ever, that  any  excess  of  soluble  plant  food  in  the  soil  may  result 
in  an  increased  vegetative  activity  of  the  trees,  accompanied  by  a 
diminution  in  the  amount  of  fruit  produced.  In  fairly  fertile 
soils  it  would  seem  that  it  is  sufficient  to  apply  in  summer  a 
moderate  dressing  of  farmyard  manure.  This  would  supply  food 
to  the  surface  roots  just  at  the  time  when  the  fruit  is  forming, 
and  would  also  serve  to  keep  the  soil  moist  and  cool.  Very  light 
soils  containing  relatively  small  quantities  of  available  mineral 
food  might  be  benefited  by  a  spring  top  dressing  of  superphos- 
phate of  lime  and  sulphate  of  potash,  at  the  rate  of  one  pound 
of  each  forked  into  the  soil  over  one  rod  of  ground  round  each 
tree.  This  would  be  in  addition  to  the  summer  mulch  of  farm- 
yard manure. 

Apple  trees  must  be  pruned.  It  is  only  by  pruning  that  the 
proper  shape  of  the  tree  is  maintained,  that  the  branches  are 
prevented  from  crossing  each  other,  that  the  tree  is  kept  open 
to  sun  and  air,  and  that  the  maximum  of  fruit  production  is 
attained.  There  are  two  main  seasons  for  pruning,  namely,  in 
December,  January,  or  February,  and  at  the  beginning  of  August. 
If  we  examine  an  apple  tree  in  the  winter  we  can  readily  make  out 
the  following  points.  First,  we  find  long  slender  shoots  bearing 
numerous  small  vegetative  buds.  If  we  follow  the  shoot  down 
from  the  tip  we  observe  a  group  of  rings  which  marks  the  position 
of  the  bud  of  the  previous  spring  from  which  the  twig  sprang. 
The  portion  of  the  twig  which  lies  between  the  rings  represents, 
therefore,  one  year's  growth.  Below  the  first  group  of  rings  we 
shall  find  at  a  short  distance  a  second  group,  lower  still  a  third 
group,  and  so  on ;  each  portion  between  two  groups  of  rings 
representing  a  year's  growth.  In  this  way  we  can  determine  the 
age  of  any  particular  portion  of  a  branch.  Besides  the  long 
slender  twigs  we  shall  observe  also  relatively  stout  branches  only 
from  one  to  four  inches  in  length,  each  terminated  by  a  large 
greyish  bud.  These  are  the  fruit  spurs,  and  the  large  buds  are 
bloom  buds  which  will  develop  fruit.  Some  of  these  spurs  are 
natural  spurs,  others  are  induced  artificially  by  the  pruning. 
If  two  shoots  are  too  close  together  or  are  growing  across  each 


THE  APPLE  159 

others'  paths,  one  of  them  should  be  severed  at  a  point  just  above 
the  rings.  Strong  shoots  must  be  shortened  by  cutting  off  about 
one-fourth  of  their  length,  medium  shoots  must  be  similarly 
shortened  to  one-half  their  length,  while  very  weak  shoots  must 
be  cut  back  to  a  point  two  buds  removed  from  the  rings.  In 
all  cases  the  shoot  is  cut  through  just  above  a  vegetative  bud, 
and  the  particular  bud  selected  must  be  so  situated  that  the 
twig  resulting  from  it  will  grow  in  such  a  direction  that  it  will 
keep  the  tree  open  and  will  not  interfere  with  the  growth  of 
other  twigs  and  branches.  As  a  rule  this  direction  should  be 
centrifugal. 

Summer  pruning  consists  in  pinching  out  those  shoots  of 
the  current  season's  growth  which  are  not  required  for  the  growth 
of  the  tree.  The  shoots  are 
shortened  so  as  to  leave 
only  about  four  buds. 

Trees  which  send  down 
deeply  into  the  soil  one  or 
more  large  roots  generally 
exhibit  exuberant  vegetative 
growth,  accompanied  by 
greatly  diminished  fruit-pro- 
ducing power.  To  remedy 
this  condition  of  affairs  the  The  codling  moth  and  caterpillar' 

tree  should  be  root  pruned ;  that  is  to  say,  we  must  endeavour 
to  encourage  the  production  of  more  fibrous  roots  by  severing 
the  above-mentioned  thick  roots.  The  operation  is  effected  in 
November.  A  circle  of  about  three  feet  radius  is  described 
round  the  tree  as  centre,  and  a  trench  is  taken  out  all  round 
to  a  depth  of  three  "  spits."  The  earth  from  the  top  spit 
is  put  in  one  heap,  that  from  the  second  in  another,  and  that 
from  the  lowest  in  a  third.  In  taking  out  the  third  spit  the 
spade  is  worked  obliquely  inwards  so  as  to  remove  the  earth 
under  the  centre  of  the  tree  and  expose  all  large  roots.  These 
are  cut  through  with  the  spade,  care  being  taken  not  to  disturb 
more  than  can  be  helped  the  large  mass  of  soil  which  is  adhering 
to  the  finer  roots.  The  earth  is  then  replaced  in  the  reverse 
order  to  that  in  which  it  was  taken  from  the  trench.  At  the 


160  THE  BOOK  OF  NATURE  STUDY 

end  of  the  operation  it  may  be  found  that  the  mass  of  earth 
round  the  roots  is  rather  deeper  in  the  ground  than  before.  To 
avoid  this  we  may,  in  the  case  of  smallish  trees,  before  remov- 
ing the  soil  from  under  the  centre,  lay  a  stout  pole  across  the 
circle  and  fasten  the  tree  to  it  with  a  rope.  This  will  prevent 
sinking. 

THE  PEAR 

The  Pear  is  propagated  by  grafting  scions  on  Quince  stocks 
in  the  same  manner  as  in  the  case  of  the  Apple.  The  Quince,  as 
regards  depth  of  rooting,  is  intermediate  between  the  Paradise 
and  the  Crab  stocks.  Hence  the  Pear,  for  this  reason,  requires 
a  somewhat  deeper  soil  than  is  required  for  dwarf  apple  trees. 
For  school  gardens,  and  indeed  for  all  small  gardens,  cordon 
pears  are  the  most  suitable.  They  may  be  trained  either  against 
a  wall  or  to  a  stake,  or  on  wires  stretched  between  fence  posts. 


PLUMS  AND  CHERRIES 

The  fruit  is  a  drupe,  consisting  of  a  hard  endocarp  enclosing 
the  seed,  a  juicy  mesocarp,  and  a  thin  epicarp.  Both  Plums 
and  Cherries  thrive  best  on  a  rather  light  soil  well  stocked  with 
available  plant  food  and  containing  lime.  Propagation  is  effected 
by  budding  or  by  grafting.  The  stock  for  Plums  is  either  the 
Mussel  Plum  or  the  St.  Julien  Plum.  For  Cherries,  two  species 
of  the  Wild  Cherry  (Prunus  Cerasus),  are  used,  namely:  Prunus 
Cerasus  for  the  Morello  and  Duke  type,  and  Prunus  Avium  (the 
Gean)  for  the  Heart  and  Bigarreau  varieties. 

THE  RASPBERRY 

This  fruit  is  indigenous  to  the  British  Isles,  and  may  often 
be  found  growing  luxuriantly  and  fruiting  abundantly  in  low-lying 
moist  plantations.  The  brownish  stems  (the  "  canes ")  arise 
from  buds  on  an  underground  root-stock  ;  they  mature  in  the  first 
year,  produce  the  leafy  fruiting  shoots  in  the  second  year,  and 
then  die  in  the  autumn.  Hence  at  that  season  all  dead  canes 
should  be  cut  out.  The  fruit  is  a  collection  of  small  one-seeded 


THE  GOOSEBERRY  161 

drupes.  The  Raspberry  requires  a  moist  rich  soil,  and  succeeds 
well  in  a  slightly  shaded  position.  The  canes  should  be  planted 
in  the  autumn  in  rows,  leaving  a  distance  of  four  feet  all  round 
between  the  plants.  They  are  best  trained  to  wires ;  failing  these 
they  must  be  loosely  tied  up  to  stakes.  The  first  spring  after 
being  planted  the  canes  must  be  cut  down  to  a  height  of  one  foot. 
The  ground  should  be  mulched  with  manure  in  winter,  and  kept 
well  stirred  with  the  Dutch  hoe  in  summer.  The  roots  are  very 
near  the  surface,  and  hence  the  ground  must  not  be  either  dug 
or  forked.  Propagation  is  effected  either  by  means  of  seeds  or 
by  taking  rooted  suckers  from  the  root-stock. 

A  valuable  hybrid,  the  Loganberry,  has  been  obtained  by 
crossing  the  Raspberry  with  the  Blackberry.  In  habit  of  growth 
the  Loganberry  resembles  the  Blackberry,  while  its  rather  acid 
fruit  is  like  a  very  large  red  Raspberry,  and  is  produced  in  great 
abundance. 

THE  GOOSEBERRY 

All  the  cultivated  varieties  are  derived  from  the  wild  Ribes 
Grossularia,  which  is  an  indigenous  bush  in  the  north  of  England, 
bearing  small  yellow,  hairy,  succulent  berries. 

To  obtain  new  varieties  of  Gooseberries  the  plants  must  of 
course  be  grown  from  seed.  The  ordinary  method  of  propagation 
is  by  cuttings.  To  obtain  these,  strong  shoots  of  the  year,  about 
fifteen  inches  in  length,  are  cut  off  close  to  the  parent  stem.  All 
except  the  top  five  buds  are  removed,  and  we  thus  obtain  a  bush 
on  a  good,  clean  stem  about  one  foot  in  height.  The  cuttings 
are  planted  in  a  shallow  vertical  walled  trench  about  eighteen 
inches  apart,  preferably  in  a  light  sandy  soil,  and  if  such  a  soil 
is  not  available  sand  should  be  thickly  sprinkled  along  the  bottom 
of  the  trench.  When  all  the  cuttings  have  been  placed  in  the 
trench,  in  a  vertical  position  the  soil  is  shovelled  into  the  trench 
and  trodden  firmly,  so  that  it  is  pressed  close  to  the  bases  of  the 
cuttings.  In  the  winter  next  but  one  following,  the  four  shoots 
which  will  have  sprung  from  the  cutting  must  be  shortened 
to  one  half  their  length,  and  in  the  summer  following  the  lateral 
shoots  from  these  must  be  pinched  back.  In  the  autumn  when 
the  cutting  is  two  years  old  the  young  bushes  are  transplanted 


VOL.  V. — II 


162  THE  BOOK  OF  NATURE  STUDY 

to  their  permanent  quarters,  where  they  should  have  a  space  all 
round  them  of  six  feet  from  bush  to  bush.  In  the  winter  following 
transplantation  the  lateral  shoots,  which  were  pinched  back  in 
the  summer,  must  be  shortened  to  one  inch.  The  object  of  this 
treatment  is  to  produce  an  open  bush  with  numerous  vigorous 
fruiting  spurs,  and  to  allow  subsequent  increase  in  size  by  annual 
extension  of  new  wood  without  choking  the  bush.  The  fruit  is 
borne  mainly  on  the  spurs,  but  also  partly  on  the  new  wood.  A 
fairly  cool  climate  suits  the  Gooseberry  best,  and  hence  it  is  seen 
to  perfection  only  in  Scotland  and  the  north  and  midlands  of 
England. 

The  plantation  should  be  mulched  with  farmyard  manure  in 
the  autumn.  In  cultivating  the  ground  round  the  bushes  care 
should  be  taken  to  avoid  injury  to  the  fibrous  roots,  which,  as  in 
the  case  of  the  Raspberry,  lie  very  close  to  the  surface.  The  hoe 
is  the  best  implement  to  use. 

For  school  gardens,  where  space  is  a  consideration,  Gooseberries 
may  be  better  sown  perhaps  on  cordons.  The  preparation  of 
these  is  too  difficult  a  matter  for  youthful  gardeners,  and  the 
Cordons  should  therefore  be  bought  from  a  nurseryman.  They 
are  trained  to  bamboo  poles  fastened  to  a  wire  trellis.  Four 
shoots  only  should  be  maintained  for  bearing  and  extension.  All 
other  shoots  should  be  summer  pinched  and  cut  back  to  one 
inch  in  length  in  winter. 

THE  CURRANT 

Of  these  there  are  three  kinds— the  White,  the  Red,  and  the 
Black  Currant.  The  ancestral  plant  is  the  (probably)  indigenous 
Wild  Currant  (Ribes  rubrum),  which  occurs  frequently  in  Scotland 
and  the  north  of  England.  As  in  the  case  of  the  Gooseberry,  while 
new  varieties  are  raised  from  seed,  propagation  of  existing  varieties 
is  effected  by  cuttings  taken  in  the  autumn.  Strong  side  shoots 
are  taken  nine  to  fifteen  inches  in  length.  About  an  inch  of  the 
upper  part  of  the  shoot  is  removed,  and  also  all  but  three  top  buds. 
The  method  of  planting  the  cuttings  is  the  same  as  that  recom- 
mended in  the  case  of  Gooseberry  cuttings.  The  form  of  bush 
to  be  aimed  at  is  one  standing  on  a  clean  stem  four  to  six  inches 


THE   STRAWBERRY  163 

high  bearing  six  main  branches.  To  secure  this  the  three  shoots 
arising  from  the  three  buds  left  on  the  cutting  are  shortened 
back  to  four  inches  in  the  next  winter  but  one  from  the  time 
of  planting  the  cutting,  and  in  the  following  spring  all  but  two 
of  the  buds  on  each  of  these  three  shoots  are  removed.  The 
bushes  may  be  transplanted  to  their  permanent  quarters  in  the 
autumn  when  two,  or  preferably,  three  years  old,  a  distance  of 
five  feet  being  allowed  between  each  pair  of  bushes. 

The  subsequent  winter  pruning  of  Black  Currants  differs  from 
that  required  by  White  and  Red  Currants  owing  to  the  fact  that 
the  fruit  of  the  Black  Currant  is  borne  mostly  on  the  young  wood, 
while  that  of  Ribes  rubrum  is  borne  on  wood  two  to  four  years  old. 
Currants  thrive  best  on  a  fairly  moist  rich  loam,  and  they  will 
produce  an  abundant  crop  of  fruit  even  in  a  north  aspect,  although 
for  the  production  of  the  maximum  of  sugar  in  the  berries  plenty 
of  sunlight  is  required.  The  ground  is  manured  and  cultivated 
in  the  same  way  as  that  occupied  by  Gooseberries.  On  light 
soils  Currants  are  benefited  by  occasional  watering  with  soapy 
water. 

THE  STRAWBERRY  (Fragaria  vesca) 

This  occurs  in  the  wild  state  in  woods  and  on  hedge  banks 
throughout  Europe,  Northern  Asia,  and  North  America.  The 
Hautboy  (Fragaria  elatior),  a  wild  British  variety,  is  distin- 
guished from  the  common  Wild  Strawberry  by  its  large  fruit,  its 
greater  height,  and  the  smaller  number  of  its  flowers  and  runners. 
Two  other  varieties  are  known,  namely,  the  North  American 
Fragaria  virginiana  and  the  South  American  Fragaria  chiloensis. 
The  Strawberry  is  a  perennial  plant  possessing  a  short  tufted  stock, 
from  which  thin  stolons  are  produced,  which  root  and  form  new 
plants  at  each  node.  The  very  numerous  modern  varieties  now 
in  cultivation  are  derived  from  crosses  between  the  varieties 
above  mentioned.  A  vertical  section  of  the  pseudo-fruit  shows 
that  it  is  composed  of  small  carpels  inserted  on  a  much  enlarged 
juicy  conical  receptacle. 

The  propagation  of  the  Strawberry  is  easily  effected  by  means 
of  rooted  runners.  The  usual  method  adopted  is  as  follows. 
The  ground  round  the  plants  is  loosened  with  a  fork  so  as  to 


164  THE  BOOK  OF  NATURE  STUDY 

provide  a  suitable  rooting  medium.  It  is  then  watered,  and  pieces 
of  brick,  tile,  or  stones  are  laid  on  the  runners  to  assist  the  roots  in 
attaching  themselves  to  the  soil.  To  obtain  vigorous  young  plants 
it  is  necessary  that  all  the  nourishment  passing  along  the  stolon 
from  each  parent  plant  should  be  devoted  to  the  support  of  one 
offspring  only,  and  consequently  we  encourage  the  stolon  to  root 
at  the  first  node,  and  as  soon  as  rooting  has  taken  place  cut  off 
the  loose  end.  In  dry  weather  frequent  watering  of  the  rooted 
plants  will  be  necessary.  They  will  be  ready  for  separation 
from  the  parent  towards  the  end  of  August,  and  they  should  be 
planted  out  in  their  permanent  quarters  at,  or  very  shortly  after, 
that  date.  In  taking  them  up  a  trowel  is  used,  and  care  should 
be  taken  not  to  break  the  ball  of  soil  in  which  the  roots  are  em- 
bedded. If,  for  any  reason,  the  bed  cannot  be  got  ready  in  time, 
the  plants  may  be  planted  in  trenches,  allowing  two  to  three 
inches  between  the  plants  and  one  foot  between  the  trenches. 
They  are  then  transplanted  in  March. 

The  best  kind  of  soil  for  Strawberries  is  a  rich  loam  inclining 
to  sandy.  Strawberries  do  not  thrive  on  a  heavy  clay.  They 
are  rather  exacting  in  their  main  requirements,  which  are  sunlight, 
moisture,  and  an  abundance  of  plant  food  in  the  soil.  The  straw- 
berry bed  must  have  been  trenched  or  heavily  manured  with 
farmyard  manure.  With  a  garden  line  and  measuring  stick  the 
young  plants  are  accurately  set  in  rows  at  a  distance  of  eighteen 
inches  between  the  plants  and  two  feet  between  the  rows.  The 
depth  of  planting  is  such  that  the  ball  of  earth  on  the  roots  is  just 
covered.  As  soon  as  the  planting  of  the  bed  is  completed  the 
soil  should  be  well  watered.  The  bed  will  require  no  more  atten- 
tion until  the  spring,  when  it  should  be  hoed.  As  soon  as  the 
flowers  have  dropped  off,  a  dressing  of  soot  or  lime  should  be 
carefully  applied  to  the  soil  all  round  the  plants,  so  as  to  prevent 
attacks  by  slugs,  and  immediately  after  a  mulching  of  long  strawy 
stable  manure  should  be  applied.  The  summer  rains  will  soon 
wash  this  clean,  and  the  plant  will  thus  be  fed  at  the  time  when 
the  fruit  is  forming.  The  strawy  coating  will  also  serve  to  preserve 
the  soil  moisture.  Water  must  be  given  from  time  to  time  if  the 
weather  is  very  dry,  and  it  is  also  desirable  a  few  weeks  before 
the  fruit  is  ripe  very  lightly  to  fork  over  the  soil  between  the 


THE   STRAWBERRY  165 

rows.  There  is  a  very  considerable  difference  in  the  date  of 
ripening  in  different  parts  of  the  British  Isles.  For  example, 
in  the  great  strawberry  district  lying  to  the  north-east  of  South- 
ampton, the  season  is  two  to  three  weeks  in  advance  of  the 
Cambridgeshire  and  Bedfordshire  season,  and  the  former  conse- 
quently monopolises  the  markets  of  the  important  northern 
industrial  centres  of  consumption,  such  as  Glasgow,  Belfast, 
and  Manchester. 

The  Strawberry  plant  produces  abundantly  only  in  its  second 
and  third  year  of  growth.  Beginning  with  the  fourth  year  there 
is  a  diminution  of  productiveness,  and  this  diminution  becomes 
more  and  more  marked  in  each  succeeding  year.  It  is  so  easy 
to  obtain  new  plants  from  the  old  ones,  as  described  above,  that 
there  is  no  excuse  for  the  retention  of  the  old  plants  beyond  their 
fourth  season,  and  at  the  end  of  that  period  at  latest  a  new  bed  in 
a  different  part  of  the  garden  should  be  formed. 


CHAPTER   XI 


FLOWERS 

IN  every  school  garden  should  be  grown  vegetables,  fruit,  and 
flowers.  The  first  two  are  of  such  economic  and  industrial  im- 
portance that  they  must  have  the  lion's  share  of  space,  thought, 
and  work ;  but,  on  the  other  hand,  flowers  have  an  aesthetic,  moral, 
and  educational  value  so  great  that  equally  they  should  be  re- 

garded  as  an  essential  in  the 
school  garden.  Small  children 
eight  to  twelve  years  of  age 
should  have  each  a  small 
plot  of  about  a  square  yard 
in  area.  Some  of  such  plots 
would  be  side  by  side,  either 
in  the  vegetable  garden  or  so 
as  to  form  little  borders  under 
the  school  walls.  Others 
would  occupy  various  corners 

°f «« sch°o1  premises-  In 

clumps  of  Annuals;  B,  shows  how  to  arrange     girls'       Schools      every      effort 
smaller  clumps ;   C,  shows  how  to  arrange     should   be    made    to    establish 

a  herbaceous  border-  not  less 

than  four  and  not  more  than 
ten  feet  in  width.  A  length  of  about  six  feet  of  such  a 
border  might  be  allocated  to  each  girl.  One  would  also  like 
to  see  a  herbaceous  border  in  every  boys'  school  garden,  whether 
belonging  to  a  day  school  or  to  an  evening  school.  Hitherto 
it  appears  that  the  exigencies  of  time,  space,  and  money 
have  been  regarded  as  obstacles.  They  are,  nevertheless,  not 
insuperable  or  even  serious  obstacles.  It  is  sometimes  urged 
that  local  education  authorities  and  school  authorities  have 
insufficient  funds  to  permit  of  indulgence  in  what  is  regarded 


166 


HARDY   ANNUALS  167 

as  the  luxury  of  flower  culture.  But  this  is  not  a  particularly 
valid  objection,  since  penny  packets  of  seeds  both  of  annual  and 
perennial  flowers  can  now  be  bought,  and  each  packet  frequently 
contains  enough  seed  to  supply  the  requirements  of  four  workers. 
Further,  the  scholars  themselves  could,  in  many  cases,  bring 
roots  of  perennials,  and  where  there  are  large  gardens  in  the 
neighbourhood,  their  owners  would  probably  be  pleased  to  make, 
out  of  their  superfluity,  donations  of  bits  of  plants  to  the  school 
garden.  Failing  a  herbaceous  border,  a  narrow  strip  of  each 
vegetable  or  fruit  plot  bordering  on  a  path  should  be  utilised  for 
flower  culture,  and  corners  of  the  garden  might  be  occupied  with 
a  few  of  the  easily  grown  ornamental  and  flowering  shrubs,  such 
as  Bamboos,  Ceanothus,  Choisya  ternata,  Butcher's  Broom, 
Periwinkle,  Almond,  Golden  English  Yew,  Buddlea  globosa, 
Broom,  Lilac  or  Syringa,  Flowering  Currant,  Shrubby  Spireas, 
and  so  on. 

It  is  not  possible  to  give  detailed  cultural  directions  for  all 
the  exceedingly  numerous  varieties  of  flowers  and  shrubs  which 
might  quite  well  be  grown  in  a  school  garden.  We  must  be 
contented  for  the  most  part  with  some  general  observations  and 
directions,  and  refer  the  reader  to  the  books  mentioned  in  the 
Bibliography  for  more  complete  information. 

HARDY  ANNUALS 

An  annual  is  a  plant  whose  life  is  limited  to  a  single  season. 
The  seed  is  sown  in  the  autumn  or  spring,  leaves,  flowers,  fruit 
and  seed  are  produced  in  the  following  summer,  and  in  the 
autumn  the  plant  dies.  Hardy  annuals  are  those  the  seedlings 
of  which  can  be  grown  in  the  open  air.  Half-hardy  annuals 
are  raised  in  pans  or  boxes  in  the  greenhouse  or  on  the  hotbed, 
and  are  planted  out  of  doors  in  June,  when  all  fear  of  prolonged 
low  temperature  during  the  night  is  at  an  end.  If  early  blooms 
of  hardy  annuals  are  required  many  of  them  may,  like  their 
half-hardy  brethren,  be  raised  in  gentle  heat.  For  outdoor 
sowing  the  end  of  March  is  the  best  time.  The  seed  bed  should 
be  as  fine  as  possible,  because  the  seeds  as  a  rule  are  very  small, 
and  in  rough  ground  would  either  not  be  in  sufficiently  close 


168 


THE  BOOK  OF  NATURE  STUDY 


contact  with  the  soil  particles,  or  would  sink  too  deeply  into 
the  soil.     They  are  best  sown  in  circular  patches  about  a  foot 


FlG.  63. — How  to  raise  tender  annuals. 
A,  a  hotbed  ;  B,  cocoa-  nut  fibre,  ashes, 
or  soil ;  C,  seedlings  in  pots  and  pans  ; 
D,  seedlings  in  boxes. 


B 

FIG.  64. — Annuals.  Thinning-out  seedlings. 
A,  watering  clump  of  seedlings  before 
thinning  is  done  ;  B,  the  result  of  thin- 
ning-out. Plants  growing  sturdily. 


and  a  half  in  diameter,  or  in  rows.  The  ground,  having  been 
dug  a  few  weeks  previously,  is  lightly  scratched  with  a  kind 
of  circular  motion  of  the  rake,  and  over  this  the  seeds  are  scattered 
evenly  and  very  thinly,  fine  soil  is  then  sifted  or  sprinkled  over 

the  seeds  and  lightly  pressed  down 
on  them.  Roughly  speaking,  the 
seeds  should  be  covered  with  soil  to 
a  depth  equal  to  their  own  diameter. 
Very  small  seeds  may  be  mixed  with 
a  little  fine  dry  sand  to  ensure  even 
and  thin  distribution.  If  sown 
thickly  the  seedlings  compete  for 
air,  moisture,  and  food,  and  suffer 
in  the  struggle.  If,  in  spite  of  all 
precautions,  the  seedlings  are  too 
thick,  they  must  be  carefully  thinned 

FiG.6S.-Annuais.  Staking.  \  shows  about  a  fortnight  after  they  appear 
how  to  stake  weakly  -  growing  above  the  surface,  and  in  any  case 
annuals  in  clumps ;  B,  shows  how  they  must  be  thoroughly  thinned 

to  stake  tall -growing  annuals ;  C,        i_  i  •       i       i  •    i  ITTI 

shows  how  to  prepare  the  tall  stakes!    Whel\  ab°Ut   &tl   mCh    ^       When 

which  should  be  painted  dark  green,   thinning  is  completely  the  plants  left 


BIENNIALS 


169 


standing  should  be  dotted  about  the  circle  at  a  distance  from 
each  other  of  six  inches  more  or  less,  according  to  the  height 
and  diameter  of  the  full-grown  plant.  If  the  plants  are  not  thus 
ruthlessly  thinned  we  shall  get  weak,  straggling,  unsightly  speci- 
mens, producing  few  blooms. 

The  following  is  a  list  of  suitable  hardy  annuals,  classified 
according  to  the  approximate  height  of  the  mature  plants. 


Sweet  Alyssum 
Dwarf  Nasturtium 


Six  inches 

Silene  pendula 
Virginian  Stock 


Aubrietia 


Bartonia  aurea 
Candytuft 
Collinsia  bicolor 
Eschscholtzia 
Linum 
Gaillardia  picta 


Twelve  inches 

Godetia 

Larkspur 

Love-in-a-mist 

Lupin 

Mignonette 

Nemophila 


Phlox  Drummondii 
Iceland  Poppy 
Saponaria 
Sweet  Scabious 
Sweet  Sultan 


Clarkia 


Eighteen  inches 
Coreopsis  Drummondi 


Tagetes 


Lupins 
Shirley  Poppy 


Twenty-four  inches  and  more 

Sunflower 
Sweet  Peas 


Convolvulus 


BIENNIALS 

A  biennial  plant  lives  for  two  years.  Leaves  and  stems  are 
produced  in  the  first  year,  and  flowers  in  the  second  year.  The 
seeds  are  sown  in  a  nursery  bed  in  May.  As  soon  as  they  can 
be  handled  they  are  transplanted  to  a  second  bed  in  rows,  allow- 
ing 6  inches  all  round  each  plant.  In  the  September  of  the 
same  year  they  are  again  transplanted,  this  time  to  their  permanent 
quarters.  The  most  suitable  biennials  for  growth  in  the  school 
garden  are  Wallflowers  (18  in.),  Sweet  Williams  (18  in.),  Fox- 
gloves (36  in.),  Canterbury  Bells  (36  in.),  and  Cornflowers  (24  in.). 


170 


THE  BOOK  OF  NATURE  STUDY 


HARDY  PERENNIAL  HERBACEOUS  PLANTS 

Many  of  these  may  be  easily  raised  from  seed  sown  in  the 
early  summer,  and  it  is  suggested  that  half  a  dozen  species  should 
thus  be  raised  in  the  school  garden  each  year.  Boxes  or  pans  are 
rilled  with  a  mixture  of  equal  parts  of  leaf-mould  and  sand 
loam,  previously  moistened.  The  seeds  should  be  sown  very 
thinly,  and  just  covered  with  the  fine  sifted  mixture  which  is 
lightly  pressed  down  over  them.  The  pans  or  boxes  are  placed 
in  a  sheltered  position,  and  care  must  be  taken  that  the  soil 
is  kept  moist,  but  not  wet.  If  the  thinning  has  been  thorough 

the  young  plants  may  be  left  in 
the  pans  until  ready  for  planting 
out  in  permanent  quarters  in  the 
following  spring.  Or,  as  in  the 
case  of  biennials,  they  may  be 
planted  out  from  the  pans  into 
good  soil  in  a  well-sheltered  posi- 
tion in  September,  being  again 
transplanted  in  the  spring.  Of 
perennials,  wrhich  may  be  grown 
from  seed  without  much  difficulty, 
the  following  are  the  best  :  - 
Campanulas,  Delphiniums,  Geum, 
perennial  varieties  of  Coreopsis, 
Flax,  Lobelia  and  Gypsophylla, 

Jacob's    Ladder,    Lychnis   chalcedonica,    Malva   moschata,    and 
Salvias. 

It  would  be  a  difficult  matter  to  name  all  the  hardy  perennials 
which  might  be  grown  in  a  school  garden,  and  since,  as  has  been 
more  than  once  hinted  in  these  pages,  the  school  garden  may 
have  to  depend  for  a  supply  on  gifts  from  kind  sympathisers, 
a  list  is  hardly  necessary.  It  may  be  useful,  however,  to  some 
readers  if  we  transcribe  here  a  list  of  fifty  best  hardy  perennials 
which  was  given  in  the  Times  of  i8th  April  1908.  These  are 
beautiful  plants,  suitable  for  a  border,  quite  hardy,  easily  grown, 
and  perennial  for  some  years. 


FlG.  66.— Planting.     A,  right  depth 
to  plant ;  B,  too  deep. 


HARDY  PERENNIALS 


171 


A  Selection  of  Fifty  of  the  Best  Hardy  Perennials. 


Delphinium  Belladonna 

Madonna  Lily 

Lilium  testaceum 

Paeony  (the  Bride) 

Aquilegia  coerulea 

Anchusa      italica      (Dropmore 

variety) 
Campanula      persicifolia,     var. 

Grandiflora 
Platycodon    grandifiorum,   var. 

Mariesii 

Oenothera  macrocarpa 
Centaurea  montana 
Nepeta  mussimi 
Armeria  cephalotes  rubra 
Polemonium  reptans 
Erigeron  speciosus 
Oriental  Poppy  (Goliath) 
Gypsophylla  paniculata 
Thalictrum  aquilegifolium 
Geranium     ibericum     platypet- 

allum 

Potentilla  nepalensis 
Coreopsis  lanceolata 
Galega  officinalis 
Tradescantia  virginica 
Trollius  asiaticus 


Statice  latifolia 

Pentstemon  barbata,  var.  Torreyi 

Hollyhocks 

Anemone  japonica 

Iris    pallida    Dalmatica    (Princess 

Beatrice) 
Viola  (Florizel) 
Pink  (albino) 
Phlox  (Coquelicot) 
Michaelmas  Daisy  (Aster  acris) 
Funkia  Sieboldii 
Haemerocallis  Thunbergii 
Kniphofia  caulescens 
Veronica  amethystina 
Linum  perenne 
Yucca  filamentosa 
Scabiosa  caucasica 
Spiraea  Aruncus 
Epilobium  angustifolium 
Sidalcea  Listeri 
Malva  moschata  alba 
Hypericum  moserianum 
Erodium  manescavi 
Saxifraga  lasiophylla 
Tiarella  cordifolia 
Incarvillea  Delavayi 


After  perennials  have  been  established  a  few  years  they  are 
generally  benefited  by  being  transplanted,  and  advantage  should 
be  taken  of  this  at  the  time  to  obtain  an  increased  number  of 
plants  by  division  of  the  roots  or  root-stock. 


BULBS 

Except  for  window  boxes,  bulbs  are  not  very  suitable  for  the 
school  garden,  for  the  reason  that,  in  the  first  place,  they  are,  com- 
pared with  seeds,  rather  expensive ;  and  in  the  second  place,  if 
left  in  the  soil  through  the  summer,  in  order  that  the  bulbs  may 
mature  for  next  year,  the  masses  of  decayed  leaves  give  a  rather 
untidy  appearance  to  the  garden.  As  a  rule  they  should  only 


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be  grown  in  a  garden  where  a  feature  is  made  of  the  herbaceous 
border.  For  such  use  the  Narcissus  is  at  once  the  most  beautiful 
and  the  easiest  of  culture.  The  bulbs  should  be  planted  in  the 
autumn,  in  clumps  about  a  foot  in  diameter.  A  circular  hole  is 
scooped  out  in  the  soil  to  a  depth  of  about  three  inches.  If 
the  soil  is  heavy  a  layer  of  sand  a  quarter  of  an  inch  deep  should 
be  sprinkled  over  the  bottom,  and  on  this  the  bulbs  should  be 
placed  at  regular  intervals  in  a  circle,  and  then  covered  with 
soil.  At  the  end  of  March  the  tips  of  the  leaves  will  appear 
above  the  surface,  and  in  the  second  half  of  April  the  flowers 
will  be  in  full  bloom.  The  period  of  blooming  extends  over  two  or 

three  weeks.  If  the  soil  is  heavy 
and  rather  poor,  few  new  bulbs 
will  be  produced,  and  there  is 
therefore  no  object  in  such  a 
case  in  allowing  the  plants  to 
stand  in  the  soil.  In  better  and 
lighter  soils  the  maturation  of 
the  new  bulbs  proceeds  until 
the  height  of  summer,  when  the 
leaves  will  begin  to  die  down. 
The  bulbs  should  then  be  dug 
up,  laid  out  in  the  sun  to  dry, 
and  stored  prior  to  replanting  in 
October. 

There  are  numerous  kinds  of  Narcissus.  The  most  suitable 
perhaps  are  :  Barri  Conspicuus,  Emperor,  Sir  Watkin,  and  Poeticus 
Ornatus. 

ROSES 

Two  or  three  Roses  should  be  grown  in  every  school  garden, 
if  only  for  the  sake  of  practice  in  the  art  of  budding.  The  details 
of  the  manipulation  have  been  given  already  under  the  head 
of  the  Apple,  and  it  only  remains  here  to  deal  with  the  question 
of  the  stock,  and  the  subsequent  treatment  of  the  budded  Rose. 
Two  kinds  of  stocks  are  employed— the  wild  English  Dog  Rose 
and  the  Manetti  stock.  The  Wild  Rose  is  a  suitable  stock  for 
almost  any  kind  of  Rose,  the  Manetti  only  for  certain  sorts.  The 


FIG.  67.— Depth  at  which  to  plant  differ- 
ent Bulbs.  A,  Snowdrops,  Crocuses, 
or  Scillas  ;  B,  Jonquils,  Tulips,  etc.  ; 
C,  Hyacinths  ;  D,  Narcissi,  Gladioli, 
etc. ;  E,  Liliums. 


ROSES  173 

scholars  should  obtain  the  stocks  from  the  hedgerows  in  late 
October  or  November.  Any  clean-growing  young  briars  with  a 
good  root  system  will  do.  A  few  of  these  should  be  brought 
into  the  garden  and  planted  in  rows,  leaving  a  space  of  one  to 
one  and  a  half  feet  all  round  each  stock.  The  operation  of  bud- 
ding is  carried  out,  as  in  the  case  of  the  Apple,  at  the  beginning 
of  August.  For  Dwarf  Roses  (and  these  are  more  suitable  for 
practice  than  standards)  the  surface  soil  is  scraped  away  from 
the  base  of  the  stock,  in  order  that  the  bud  may  be  inserted  as 
low  down  as  possible  on  the  stem,  thus  diminishing  the  possi- 
bility of  the  production  of  suckers.  The  bud  having  been  taken 
and  inserted,  nothing  more  remains  to  be  done  except  to  release, 
at  the  end  of  a  month,  the  bast  or  worsted  thread  used  to  keep 
the  bud  in  position.  In  March  following  the  stock  is  cut  off 
at  a  joint  two  or  three  inches  above  that  from  which  the  inserted 
bud  is  now  growing.  In  the  October  following  the  bushes  are 
transferred  to  their  permanent  quarters.  A  hole  is  dug  one  foot 
in  diameter  and  one  foot  deep,  and  into  the  bottom  of  this  is 
worked  some  well-decayed  leaf-mould  and  dung.  In  this  the 
Rose  is  placed  at  such  a  depth  that  the  roots  are  within  two  inches 
of  the  surface. 

Roses  of  one  kind  or  another  may  be  grown  on  almost  any 
soil  except  a  very  raw  heavy  clay.  That  they  will  grow  and 
bloom  well  on  a  thin  sandy  soil  is  evidenced  by  the  fine  dis- 
play of  Roses  which  may  be  seen  in  the  summer  in  the  gardens 
of  the  Royal  Horticultural  Society  at  Wisley.  On  such  a 
soil,  however,  cow  dung  and  loam  must  be  well  worked  into 
the  soil  around  the  Rose  bush,  as  Roses  are  "  heavy  feeders," 
and  the  bushes  must  be  mulched  each  year  with  the  same 
manure. 

For  bushes,  plant  Edith  Gifford,  Caroline  Testout,  Madame 
Fernet  Ducher  ;  for  arches  and  walls,  William  Allan  Richardson, 
Crimson  Rambler,  Dorothy  Perkins. 

SWEET  PEAS 

In  a  school  garden  not  provided  with  a  greenhouse  or  frame, 
Sweet  Peas  may  be  sown  during  March,  April,  and  May  for  a 


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THE  BOOK  OF  NATURE  STUDY 


succession  of  blossoms.  A  deeply  cultivated  soil,  well  stocked 
with  plant  food,  and  fairly  retentive  of  moisture,  is  required  for 
the  best  results.  The  seeds  may  be  sown  either  in  circular  clumps 
or  rows.  In  either  case  the  soil  is  taken  out  to  a  depth  of  about 
two  inches,  and  the  seeds  are  planted  separately  at  a  distance 
apart  of  from  two  to  three  inches.  They  are  covered  with  soil 
to  a  depth  of  one  inch.  To  protect  them  from  attacks  by  birds, 
pieces  of  black  thread  to  which  white  feathers  are  fastened  at 
intervals  should  be  stretched  across  the  bed.  Slugs  are  trouble- 
some at  the  time  the  young  plants  show  above  ground,  and  a  good 


FIG.  68. — Sweet  Peas.  Sowing  seeds  in 
drills.  A,  A,  drills  14  in.  wide,  2  in. 
deep ;  B,  space  between  drills,  6  ft. 
wide. 


FIG.  69.— Sweet  Peas.  Sowing  seeds 
in  clumps.  A,  A,  circles  drawn 
42  in.  in  diameter ;  B,  circles  4  ft. 
apart ;  C,  holes  for  seeds  or  plants. 


dressing  of  soot  should  therefore  be  given.  As  soon  as  the  plants 
are  four  inches  high  they  must  be  supported  with  small  twigs, 
and  when  six  or  eight  inches  high  they  must  be  staked  with 
longer  twigs  (four  feet  or  more  in  height).  Drought  is  very 
injurious,  and  it  is  therefore  important  to  maintain  a  good  sur- 
face mulch  with  the  hoe  during  the  period  of  growth,  and 
to  give  a  top  dressing  of  rotted  manure  at  the  time  of  flower- 
ing. There  are  numerous  varieties.  Among  the  best  are : 
Dorothy  Eckford  (white) ;  Black  Knight  (bronze) ;  Navy  Blue, 
Countess  Cadogan  and  Lord  Nelson  (blue)  ;  Prima  Donna, 
King  Edward,  Mars  and  Adonis  (pinks  or  reds)  ;  Henry  Eckford 
(orange). 


GERANIUMS  175 

GERANIUMS 

It  is  not  a  very  difficult  matter  to  raise  geraniums  from  seed. 
The  seeds  are  sown  in  pans  containing  a  mixture  of  equal  parts 
of  loam  and  sand.  If  a  spent  hotbed  is  available  the  seeds  may 
be  sown  in  March.  If  there  is  no  hotbed  the  sowing  must  be 
done  at  the  end  of  April  and  the  pans  kept  indoors.  Germina- 
tion takes  place  quickly,  and  after  thinning,  the  young  plants, 
when  two  inches  high,  are  transferred  to  separate  pots  in  which 
they  must  be  kept  indoors  through  the  following  winter. 

The  ordinary  method  of  propagation  is  by  means  of  cuttings 
taken  either  in  July  or  in  March.  For  summer  cuttings,  good 
strong  side  shoots  are  taken  off  with  a  clean  cut,  trimmed,  and 
firmly  inserted  in  somewhat  sandy  soil  in  a  sheltered  position 
out  of  doors.  Care  must,  as  usual,  be  taken  that  the  base  of 
the  cutting  is  in  close  contact  with  the  soil.  Root  formation 
proceeds  rapidly,  and  at  the  beginning  of  October  the  rooted 
cuttings  will  be  ready  to  be  taken  up,  potted,  and  stored  for 
the  winter,  either  in  a  frame  or  indoors. 

In  the  case  of  spring  cuttings,  the  slips  are  taken  off  old  plants 
kept  over  from  the  previous  summer.  Gentle  heat,  however,  is 
required  for  these  spring  cuttings,  and  consequently  the  method 
cannot  be  adopted  unless  the  school  garden  possesses  a  heated 
greenhouse  or  a  hotbed. 

Window  geraniums  planted  in  pots  may  be  kept  through  the 
winter  (as  is  done  by  cottagers)  in  any  room  the  temperature 
of  which  during  the  winter  nights  does  not  fall  to  a  lower 
temperature  than  40°  F.  Where  it  is  desired  to  keep  summer 
bedded  Geraniums  through  the  winter,  they  are  best  packed  closely 
with  the  earth  round  their  roots  in  boxes,  which  are  then  stored 
in  some  place  free  from  frost. 

THE  HERBACEOUS  BORDER 

The  mainstay  of  the  herbaceous  border  is  a  variety  of  soft- 
wooded  hardy  perennial  plants.  These  are  supplemented  by 
such  spring  flowering  bulbous  plants  as  Snowdrops,  Squills, 
Crocuses,  Irises,  and  Narcissus,  by  annuals,  and  by  a  few  small 


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THE  BOOK  OF  NATURE  STUDY 


compact  rooting  bushes  and  shrubs,  such  as  Lavender,  Rosemary, 
and  Dwarf  Roses.  The  aim  should  be  to  supply  a  continuous 
variety  of  bloom  and  greenery  from  spring  to  autumn,  to  arrange 
contrast  of  colour  and  form,  and  yet  to  maintain  a  plan  under- 
lying the  maze  of  plants.  While,  generally  speaking,  the  smaller 
plants  are  placed  towards  the  front  of  the  border,  and  the  taller 
ones  towards  the  back,  this  should  not  be  done  with  mathematical 
accuracy.  The  tallest  plants  should  not  be  quite  at  the  back, 
and  some  of  the  smaller  plants  should  be  placed  between  or  even 
behind  the  line  of  the  taller  ones.  The  shrubby  plants  above 
mentioned  should  constitute  the  skeleton  of  the  border,  and 
should  be  planted  in  a  regular  slightly  zigzag  line,  at  intervals 
along  its  length.  The  clumps  of  bulbs  should  not  be  planted  in 

isolated  groups,  but 
near  some  plant  or 
shrub  which  will  act 
as  a  background  to 
them  when  they  are 
in  flower.  The  front 
part  of  the  border 
may  be  occupied  by 
Pinks,  Sweet  Alys- 
sum,  Aubrietia,  Saxi- 
frage, Pansies,  Violas, 
Dwarf  Larkspurs,  arranged  irregularly  but  at  equal  intervals.  Be- 
hind these  and  between  the  shrubs  would  come  the  tall  perennials. 
The  clumps  of  annuals  will  be  similarly  arranged,  approximately 
according  to  height,  among  the  permanent  occupants  of  the  border. 
Above  all  things,  do  not  crowd  the  border,  but  let  every  plant, 
or  group  of  plants,  occupy  a  distinct  space,  with  intervals  between 
sufficient  to  cultivate  with  the  Dutch  hoe.  Neatness  is  essential, 
and  there  can  be  no  neatness  when  the  plants  are  jostling  each 
other. 

PLANTS  IN  WINDOWS 

For  town  schools,  and  for  all  girls'  schools,  whether  in  town 
or  country,  window  gardening  is  an  excellent  means  of  developing 
an  interest  in  flower  culture.  Window  boxes  may  be  constructed 


FlG.  70.— End  view  of  plants  in  borders, 
border  ;  B,  back  of  border. 


A,  front  of 


PLANTS  IN  WINDOWS  177 

very  cheaply  by  the  scholars.  The  dimensions  of  the  window 
sill  should  be  taken  and  a  local  timber  merchant  asked  to  supply 
half-inch  deal  boards,  nine  inches  in  width  and  of  a  length  rather 
less  than  that  of  the  sill.  These  can  then  be  nailed  together  to 
form  a  box  and  painted.  The  best  colour  is  green,  though  for 
trailing  plants,  such  as  Ivy  Geranium,  white  looks  very  well,  pro- 
vided the  box  is  freshly  painted  each  year.  Probably  a  brace 
and  bit  can  be  borrowed  for  the  purpose  of  boring  the  drainage 
holes  in  the  bottom  of  the  box.  In  a  box  two  feet  long  by  nine 
inches  wide,  eight  or  ten  such  holes,  half  an  inch  in  diameter, 
should  be  bored  irregularly,  so  as  not  to  produce  a  tendency  to 
split.  In  the  bottom  of  the  box  place  a  layer  of  broken  flower 
pot,  or  failing  these,  any  pieces  of  broken  brick,  or  even  stone. 
Over  this  layer  sprinkle  a  thin  coating  of  dead  leaves,  or  of  broken 
turf,  so  as  to  prevent  the  soil  from  getting  down  amongst  the 
drainage  pieces.  The  best  soil  available  should  then  be  filled 
in,  to  within  an  inch  of  the  top,  and  gently  pressed  down.  Good 
garden  soil  should  be  used,  and  this  may  with  advantage  be 
mixed  with  a  little  clean  white  sand,  in  the  proportion  of  about 
three  spadefuls  of  garden  soil  to  one  spadeful  of  sand — rather 
more  sand  for  bulbs  and  less  for  other  flowers.  If  well  rotted 
turf  can  be  had  a  little  of  this  mixed  with  the  soil  will  help.  It 
is  important  to  secure  good  open  soil  for  the  window  box,  because 
the  sides  of  the  window  box  are  practically  non-porous  to  air 
and  water,  and  therefore  if  a  heavy  soil  were  used  the  roots  would 
not  be  able  to  obtain  their  proper  supply  of  air.  For  systematic 
window  gardening  we  require  at  least  two  boxes  for  each  sill, 
one  for  spring  and  the  other  for  summer  plants.  The  spring 
window  box  is  prepared  in  the  autumn,  and  for  the  purpose  we 
rely  mainly  on  bulbs.  In  it  plant  bulbs  of  Narcissus,  such  as 
Narcissus  poeticus  and  Barrii  conspicuusJ  These  in  clumps  of 
three,  the  distance  between  the  bulbs  in  a  clump  being  about 
one  inch,  and  the  distance  between  the  clumps  about  three  inches. 
In  the  spaces  between  the  clumps  plant  similarly  other  clumps 
of  Snowdrops,  Anerriones,  Scillas,*  and  yellow/  purple,  and  white 
Crocuses.  These  bulbs  will  give  a  succession  of  bloom  through 
February,  March,  and  April. 

For  the  summer  box  there  is  a  "practically  unlimited  choice 

VOL.  V. 12 


178 


THE  BOOK  OF  NATURE  STUDY 


of  plants.  If  a  hotbed  has  been  made  in  February  we  can  raise 
early  seedlings  of  most  of  the  better  hardy  annuals,  and  these 
can  be  transplanted  into  the  window  box  in  March.  They  must 
not  be  exposed  to  the  cold  air  all  at  once,  but  must  be  gradually 
hardened  by  taking  them  out-doors  for  a  short  time  each  day 
when  it  is  sunny  and  warm.  For  the  rest  of  the  time  the  box 
must  be  kept  inside  in  a  light,  moderately  sunny,  airy  place.  By 
the  middle  of  April,  unless  the  weather  is  cold  and  windy,  the  box 
may  be  placed  permanently  outside. 

If  we  have  no  hotbed,  the  young  plants  must  be  raised  in 

a  sheltered  warm  part  of  the 
garden,  the  seeds  being  sown  in 
March.  Speaking  generally,  it  is 
not  desirable  for  school  purposes 
to  purchase  plants  raised  else- 
where. It  is  much  better  for  the 
pupils  to  be  acquainted  at  first 
hand  with  the  full  history  of  the 
plants  they  are  handling.  Hardy 
perennial  and  biennial  plants  in- 
tended for  the  window  box  should, 
of  course,  be  raised  in  seed  beds 
in  the  preceding  late  spring  or 
FIG.  71.— Bulb-growing  in  glasses,  and  in  early  summer,  transplanted  into 

fresh  beds  in  autumn,  and  again 
transplanted  in  March  into  the 
window  box. 

Instead  of  window  boxes  we  may  use  large  flowerpots,  and 
almost  everything  which  has  been  said  above  will  apply  also  to 
this  method  of  window  gardening.  Annual  creepers  may  be 
made  especially  effective  if  sown  thinly  in  large  flower  pots,  and 
trained  to  climb  up  trellis  work  (or  any  home-made  support) 
placed  on  either  side  of  windows  or  doors.  Some  of  these  grow 
with  extraordinary  rapidity,  and  produce  an  abundance  of  flowers 
and  foliage.  For  this  purpose  employ  Canariensis,  Hop,  Con- 
volvulus, and  climbing  Nasturtium.  The  seeds  are  sown  in  early 
March,  in  pots  six  to  eight  inches  in  diameter,  containing  good 
soil.  As  soon  as  the  young  plants  are  up  they  must  be  thinned, 


Moss  fibre  in  vessels  without  drain- 
age. Receptacles  suitable  for  Narcissi, 
Tulips,  and  Snowdrops. 


TOWN  GARDENING  179 

and  the  thinning  should  be  repeated  a  week  or  two  later,  so  as 
to  leave  not  more  than  four  plants  situated  at  approximately 
equal  distances  from  each  other.  A  single  plant  would,  in  fact, 
be  sufficient,  but  it  is  advisable  to  allow  for  contingencies. 


TOWN  GARDENING 

The  principal  difficulties  which  arise  in  gardening  in  towns 
are  want  of  space,  poverty  of  soil,  and  unsuitable  atmospheric 
conditions.  The  first  is  insuperable,  the  second  can  be  removed 
by  tillage  carried  out  at  the  proper  time,  and  by  the  use  of  well 
rotted  stable  manure.  Adverse  atmospheric  conditions  are  due 
in  part  to  the  fact  that  the  air  of  large  towns  contains  relatively 
large  quantities  of  sulphuric  acid  and  carbon,  which  when 
deposited  choke  the  pores  and  injure  the  texture  of  the  leaves 
of  the  plants.  Further,  the  dust  and  soot-laden  atmosphere 
hinders  the  passage  of  sunlight.  These  effects  are  most  marked 
during  the  winter,  when  there  is  a  greatly  increased  domestic 
consumption  of  coal  and  gas,  coupled  with  a  decrease  in  the 
amount  of  light  and  heat  received  from  the  sun.  From  this  it 
follows  that  the  plants  which  suffer  most  are  those — the  hardy 
perennials — which  remain  out  of  doors  the  whole  year  round. 

Many  annuals  and  bedding  plants  may  be  grown  almost  as 
successfully  in  town  gardens  as  in  country  and  semi-urban  districts. 
The  following  have  shown  themselves  best  able  to  resist  the 
adverse  conditions  attaching  to  a  garden  in  a  large  town  : — 
Coreopsis,  Sunflower,  Marigold,  Nasturtium,  Scabious,  Clarkia, 
Nigella,  Lupin,  Sweet  Pea,  Mignonette,  Virginia  Stock,  Sweet 
Alyssum,  Larkspur,  Hop,  Canariensis,  Convolvulus,  Candytuft, 
Snowdrop,  Crocus,  Hyacinth,  Narcissus,  Iris,  Pink,  Auricula,  Poly- 
anthus, Wallflower,  Aubrietia,  Arabis,  Hardy  Ferns,  Ivy,  Virginia 
Creeper,  Forsythia,  Pyracanthus,  Cotoneaster. 


CHAPTER  XII 


INSECT  AND  FUNGOID  ENEMIES  OF  GARDEN  CROPS 

PROBABLY  every  plant  supplies  either  food  or  shelter  or  both 
to  one  or  more  insects  or  other  animals  and  fungi,  and  where, 
as  in  the  farm  garden  or  orchard,  plants  are  growing  in  greater 
numbers  than  is  the  case  on  land  not  cultivated,  the  abundance 
of  the  food  or  shelter  thus  provided  encourages  the  multiplication 

of  objectionable  guests.  In 
the  United  States  of  Amer- 
ica, where  fruit  plantations 
frequently  extend  to  hun- 
dreds of  acres,  it  is  a  matter 
of  life  and  death  for  the 
fruit  grower  to  take  all 
possible  precautions  against 
a  fungus  or  insect  obtaining 
a  foothold  on  his  planta- 
tions. In  this  country, 
generally  speaking,  crops 
are  not  cultivated  on  so 
large  a  scale,  and  the  neces- 
sity for  combating  the 
spread  of  insect  and  fungoid  enemies  is  not  yet  fully  and  generally 
recognised,  although  the  losses  yearly  in  one  crop  or  another  are 
sufficiently  serious. 

In  order  to  wage  war  successfully  with  plant  pests  it  is 
essential  to  possess  a  complete  knowledge  of  the  life-history  of 
the  pest,  so  as  to  know  where  it  is  lurking  at  each  stage  of  its 
existence,  and  at  what  stage  it  can  best  be  attacked.  The  number 
of  such  pests  is  considerable ;  probably  many  have  not  yet  been 
recorded,  and  in  the  case  of  many  of  those  which  have  been 
recognised  as  causing  injury  to  crops,  we  are  not  yet  in  possession 

180 


FIG.  72. — The  Winter  Moth. 


COMMON  VAPOURER  MOTH  181 

of  all  the  important  facts  as  to  their  lives  and  habits.  It  is  not 
beyond  the  powers  of  school  children  to  study  the  life-histories 
of  a  few  of  the  commoner  noxious  insects,  and  such  a  study,  if 
carried  out  with  thoroughness  on  some  of  those  which  are  quite 
common,  can  be  made  highly  instructive  and  interesting.  An 
investigation  can,  for  instance,  be  made  of  the  life-history  of  the 
common  winter  moth ;  and  this,  if  completely  carried  out, 
establishes  a  sort  of  type  in  the  mind  of  the  young  observer. 
The  life-histories  of  fungi  involve  the  use  of  the  microscope,  and 
is  not  so  suitable  a  subject  for  school  study,  although  it  is  desirable 
to  encourage  the  young  students  to  look  for  blotches  and  dis- 
colorations  on  leaves  and  shoots.  These  are  frequently  attributed 
by  gardeners  and  farmers  to  frost  and  cutting  winds,  when  they 
are,  in  fact,  the  outcome  of  attacks  by  fungi  or  aphides. 

Prevention  is  better  than  cure,  and  fortunately  there  are  a 


FIG.  73. — Common  Vapourer  Moth,  with  Caterpillar  and  wingless 
female  Moth. 

number  of  ways  in  which  attacks  may  be  forestalled.  For 
example,  if  the  soil  is  turned  up  in  the  autumn,  any  insect  larvae 
or  pupae,  which  may  be  buried  in  it,  will  be  exposed  to  the 
weather  and  killed,  or  will  be  eaten  by  the  birds.  Insectivorous 
birds,  such  as  the  titmouse  or  the  starling,  should  therefore 
be  encouraged.  Again,  although  fungi  and  insects  can  usually 
maintain  themselves  on  more  than  one  species  of-  plant,  the 
chances  are  that  if  ground  occupied  one  summer  with  a  given 
species  of  plant  is  occupied  the  following  summer  with  a  different 
species,  or,  better  still,  with  a  plant  belonging  to  a  different  order, 
the  insect  or  fungus  which  throve  on  the  former  will  be  starved 
out  by  the  latter.  Hence  regular  change  of  cropping  is  necessary. 
Crops,  which  owing  to  bad  tillage,  unfavourable  weather,  or 
poverty  of  soil,  are  not  growing  vigorously,  are  not  in  a  position 
to  resist  the  attack  of  fungi,  and  crops  in  the  seedling  stage  are 
also  very  frequently  the  victims  of  attack. 


182 


THE  BOOK  OF  NATURE  STUDY 


When  the  pest  has  established  itself  in  quantity  the  remedial 
operations  include  spraying,  and  in  some  cases  handpicking  or 
trapping. 

Aphides,  scale  insects,  and  beetles  feed  during  both  the  larval 
and  adult  stages  ;  moths  and  sawflies,  during  the  larval  stage 
only.  In  combating  insect  attacks,  the  eggs  and  chrysalids  may 
be  destroyed  in  the  winter,  the  larvae  in  the  summer.  Moss, 
lichen,  and  dead  bark  afford  shelter  to  the  eggs  during  the  winter, 
and  consequently  care  should  be  taken  to  keep  the  trunks  of 

fruit  trees  as  clean 
as  possible.  Fungi 
frequently  make 
wounds  and  cut  sur- 
faces their  point  of 
attack  in  the  case 
of  fruit  trees,  and 
such  surfaces  should 
therefore  be  cauter- 
ised with  tar  if 
fungus  pests  are  pre- 
valent. 

For  spraying,  on 
a  small  scale,  a  knap- 
sack sprayer  is  re- 
quired, costing  about 

FIG.  74.— Small  Ermine  Moth  and  Caterpillar.  Moth  twice  thirty  shillings.  Such 
natural  size ;  larvae  and  web  about  natural  size.  (By  Q  Sprayer  delivers  the 
permission  of  the  Board  of  Agriculture)  Solution  in  a  fine 

mist,  which  coats  leaves,  twigs,  and  stem,  but  is  not  in  suffi- 
cient quantity  to  run  off  the  plant  and  so  be  wasted  or  injure 
the  roots.  Spraying,  if  done  at  all,  must  be  done  with 
thoroughness,  and  the  jet  must  therefore  be  directed  to  all  sides 
of  the  stem,  and  also  the  under,  as  well  as  the  upper,  sides  of 
the  leaves. 

WINTER  WASH. — This  may  be  applied  to  fruit  trees  every 
second  or  third  year.  It  will  remove  moss  and  lichen,  and  kill 
a  good  many  eggs  and  chrysalids.  It  should  be  applied  in 


FIG.  75.— The  Pear  Sawfly— 
Erlocampa  (enlarged). 


SUMMER  SPRAYING 

February.     The  following   recipe  is  recommended  : — Soft  soap, 
\  Ib. ;  paraffin,  5  pints ;  caustic  soda,  2  Ibs. ;  water,  9^  gallons. 

Caustic  soda  in  solution  attacks  the  skin  of  the  hands,  and 
may  cause  serious  wounds.  In  handling  this  solution,  therefore, 
leather  or  rubber  gloves  should  be  worn.  The  mixture  must  be 
continually  stirred,  otherwise  the  soap  and  the  paraffin  will  rise  to 
the  surface  of  the  liquid. 

A  simple,  but  not  so  generally 
effective,  winter  wash  for  apple  trees 
is  made  by  employing  a  mixture  con- 
taining 15  Ibs.  of  quicklime,  2  Ibs.  of 
common  salt  in  8  gallons  of  water. 
The  salt  is  dissolved  in  the  water,  the 
quicklime  is  slaked  just  before  using 
by  adding  to  it  just  so  much  water  as 
will  cause  it  to  crumble  into  finely 
powdered  slaked  lime.  It  is  then 
stirred  into  the  salt  solution,  and  the 
mixture  painted  on  to  trunk  and 
branches  with  a  large  brush. 

SUMMER  SPRAYING. — While  winter 
washing  should  be  regarded  as  a 
matter  of  routine  in  fruit  planta- 
tions, summer  treatment  should,  as 
a  rule,  only  be  done  when  a  serious 
insect  or  fungus  attack  is  imminent. 
Different  pests  are  injured  or  de- 
stroyed by  different  substances,  and 
in  different  ways.  Lead  arseniate  pro- 
bably poisons  the  insects,  paraffin 
either  poisons  or  corrodes  them.  Carbon  bisulphide  injected  into 
the  soil  destroys  the  grubs,  soft  soap  stops  up  the  breathing 
pores.  Fungi  can  be  effectually  removed  only  by  treating  them 
at  regular  intervals  with  a  solution  of  either  copper  sulphate  or 
sulphide  of  potassium,  which  destroys  the  spores.  It  is  obviously 
beyond  the  scope  of  this  book  to  go  into  this  matter  in  greater 
detail.  It  will  be  sufficient,  perhaps,  to  give  here  detailed 


184  THE  BOOK  OF  NATURE  STUDY 

accounts  of  the  life-histories  of  a  few  pests,  the  preventive  and 
remedial  treatment  of  which  is  established  on  a  sure  foundation. 

THE  WINTER  MOTH. — The  essential  fact  on  which  the  treat- 
ment of  this  insect  pest  depends  is  that  the  females  have  only 
rudimentary  wings,  and  in  consequence  are  unable  to  fly.  Male 
and  female  emerge  from  the  pupae,  at  the  earliest,  in  October. 
The  females  crawl  up  the  stems  of  the  Apple  trees  to  join  the 
males,  after  which  they  lay  their  eggs  on  twigs,  branches,  or 
trunk  of  the  tree,  in  any  convenient  crevice.  The  caterpillars  are 
hatched  from  the  eggs  in  March,  and  begin  to  feed  on  the  leaves 
of  the  tree.  They  are  "  loopers,"  measuring  nearly  an  inch  in 
length,  and  bright  green  in  colour  with  pale  lines.  They  leave 
the  tree  in  June,  bury  themselves  in  the  ground  and  pupate, 
emerging  as  moths  in  October  or  November.  The  remedy  is  to 
prevent  the  female  from  crawling  up  the  trunk,  and  this  is  effected 
by  grease  banding,  which  consists  in  tying  round  the  tree  trunk  a 
band  of  grease-proof  paper  six  inches  wide  and  coating  this  with 
cart  grease.  The  band  should  be  placed  not  far  from  the  surface 
of  the  soil,  since  eggs  may  be  laid  quite  low  down  on  the  trunk 
of  the  tree.  When  the  females  attempt  to  crawl  over  the  grease 
band  they  stick  on  it  and  may  be  removed  and  destroyed.  Since 
the  moths  begin  to  emerge  from  the  pupae  in  October  it  is  plain 
that  the  grease  bands  must  be  put  on  in  the  last  week  of 
September. 

THE  GOOSEBERRY  SAWFLY.  -  -  The  sawfly  emerges  from  the 
ground  in  April  and  May,  and  lays  its  eggs  on  the  under  surface  of 
the  leaves  ;  the  caterpillars  hatched  from  these  eggs  begin  to  con- 
sume the  leaves  in  May,  and  may  defoliate  the  whole  bush.  The 
caterpillars  when  young  are  green  with  black  spots  ;  when  fully 
grown  some  of  the  segments  are  orange  coloured,  and  the  cater- 
pillar is  then  nearly  an  inch  long.  They  then  go  into  the  ground 
and  construct  cocoons.  From  some  of  these  sawflies  are  produced 
in  about  twenty  days  ;  others  remain  in  the  soil,  pupate  in  spring, 
and  produce  the  April  and  May  sawflies.  To  destroy  the  pests 
rake  gas  lime  into  the  soil  round  the  tree  in  March.  To  destroy 
the  caterpillars,  spray  the  tree  with  an  emulsion  of  paraffin  oil 


THE  CURRANT  GALL  MITE         185 

made  up  in  the  proportions  of  6  Ibs.  of  oil  to  10  gallons  of 
water. 

THE  CURRANT  GALL  MITE  (Big  Bud). — Attacks  of  this  pest 
cannot  be  mistaken.  The  buds  appear  large  and  round  instead 
of  being  pointed,  and  if  opened  and  examined  with  a  good  magni- 
fying glass  will  be  found  to  contain  large  numbers  of  white  mites. 
The  mites  begin  hatching  in  March,  and  from  May  to  June  lay 
their  eggs  in  the  buds,  from  some  of  which  mites  are  hatched  the 
same  summer,  while  others  remain  unhatched  until  the  following 
spring.  Some  of  the  mites  also  remain  in  the  buds  through  the 
winter,  and  others  hide  in  the  roots.  There  is  no  certain  remedy 
other  than  picking  off  and  burning  infested  buds,  or  in  bad  cases 
digging  up  and  destroying  the  whole  bush.  In  some  cases,  how- 
ever, it  is  stated  that  the  pest  has  been  destroyed  at  the  time  of 
emerging  from  the  previous  year's  buds  in  March,  April,  and  May 
by  dusting  the  bushes  at  fortnightly  intervals  with  a  mixture  of 
powdered  quick  lime  and  flowers  of  sulphur,  in  the  proportion 
by  weight  of  one  of  the  former  to  two  of  the  latter. 

THE  POTATO  DISEASE. — The  commonest  and  most  serious 
disease  from  which  Potato  plants  suffer  is  that  caused  by  a  fungus 
called  Phytophthera  infestans.  The  disease  appears  every  year, 
and  apparently  no  variety  is  capable  of  resisting  it,  although  it 
is  stated  that  some  varieties  suffer  less  than  others.  The  first 
symptoms  of  disease  should  be  looked  for  between  the  last  week 
of  June  and  the  first  week  of  August,  when  the  mycelium  of  the 
fungus  may  be  found  in  white  patches  on  the  under  surface  of  the 
leaves.  The  hyphae  penetrate  into  the  tissues  of  the  leaves, 
feeding  on  the  nutritive  material  which  should  go  to  nourish  the 
plant,  and  pass  down  through  the  stalks  into  the  tubers.  The 
leaves  show  brown  blotches  under  the  patches,  and  in  severe 
cases  the  whole  of  the  plant  above  ground  becomes  dark  brown 
and  gives  out  an  offensive  smell.  Besides  the  branches  which 
grow  down  into  the  stem  of  the  plant,  other  branches  grow  out 
through  the  stomatic  openings  on  the  under  side  of  the  leaves. 
These  produce  conidia  containing  spores.  When  the  conidia  are 
ripe  they  drop  off,  are  blown  about  by  the  wind,  and  ultimately 


i86  THE  BOOK  OF  NATURE  STUDY 

burst,  scattering  the  spores,  which,  if  conditions  of  warmth, 
moisture,  and  presence  of  the  host  plant  are  favourable,  germinate 
and  give  rise  to  fresh  infection.  Continuity  of  the  life  of  the 
fungus  is  maintained  by  means  of  resting  spores,  which  remain 
dormant  during  the  winter  and  resume  growth  in  the  following 
summer. 

To  prevent  the  disease,  care  should  be  taken  to  burn  all  diseased 
leaves  and  stalks.  Diseased  tubers  may  be  fed  to  pigs  after  being 
first  thoroughly  cooked  by  boiling. 

Fortunately,  the  disease  may  be  successfully  combated  in  its 
early  stages  by  spraying  the  plants  with  Bordeaux  mixture,  and 
as  the  disease  is  so  common  it  is  advisable  to  spray  all  Potato 
crops  whether  the  presence  of  the  fungus  has  been  observed  or 
not.  Bordeaux  mixture  is  made  as  follows.  Dissolve  10  ounces 
of  crystalline  copper  sulphate  in  half  a  gallon  of  water.  Take 
half  a  pound  of  quicklime  and  slake  it  by  adding  water  to  it  a 
little  at  a  time  until  the  lime  becomes  hot  and  crumbles  to  a 
powder.  When  cool  add  to  it  12  to  15  gallons  of  water  in  a  tub 
and  stir  once  or  twice.  Allow  to  settle,  and,  when  clear,  measure 
out  8J  gallons  of  the  lime  water  and  mix  it  with  the  copper  sul- 
phate solution.  Add  sufficient  water  to  make  up  to  10  gallons. 
Copper  sulphate  solution  cannot  be  made  in  a  metal  vessel  owing 
to  the  chemical  action  which  would  take  place.  A  wooden  tub 
should  be  employed.  For  spraying  use  a  knapsack  sprayer,  and 
in  applying  the  jet  of  liquid  endeavour  to  get  as  much  as  possible 
on  the  under  surfaces  of  the  leaves.  For  this  purpose  one  operator 
should  direct  the  spray  while  a  second  turns  up  the  leaves  with  a 
stick.  The  first  spraying  should  be  carried  out  at  the  beginning 
of  July,  and  should  be  repeated  once  or  twice  at  fortnightly 
intervals. 

BIBLIOGRAPHY 

GENERAL  GARDENING.— (a)  Thompson's  Gardeners'  Assistant,  published  in 
six  volumes  at  8s.  each,  or  in  two  volumes  at  253.  each,  (b)  Sanders,  Encyclopedia 
of  Gardening.  35.  6d.  (c)  Board  of  Agriculture  :  Sectional  volumes  of  Leaflets, 
namely—"  No.  5.  Fruit  Trees  and  Farm  and  Garden  Crops."  Percival,  Artificial 
Manures  and  how  to  use  them  in  the  Garden,  Orchard,  and  Allotment.  6d. 

SPECIAL  SECTIONS  OF  GARDENING. — (a)  Wythes,  The  Book  of  Vegetables.  2s.  6d. 
(b)  Thomas,  The  Book  of  the  Apple.  2s.  6d.  (c)  Arnott,  The  Book  of  Bulbs.  2s.  6d. 
(d)  Report  of  the  Departmental  Committee  on  Fruit  Industry.  Cd.  2589.  4jd. 


BIBLIOGRAPHY  187 

INSECT  AND  FUNGOID  PESTS; — (a)  Pearson,  The  Book  of  Garden  Pests.    2s.  6d. 

(b)  Pickering  and  Theobald,  Fruit  Trees  and  their  Enemies,    is.  6d.     (c)  Various 
issues  of  the  Journal  of  the  South- Eastern  Agricultural  College,  Wye.  6s.  per  volume. 
(d)  Board  of  Agriculture  :  Sectional  Leaflets,  Nos.  9,  10,  n,  and  12. 

TECHNICAL  BOTANY. — (a)  Percival,  Agricultural  Botany.    8s.  6d.     (b)  Sorauer, 

Plant  Physiology. 

SOIL  SCIENCE. — (a)  Warington,  Physical  Properties  of  Soil.  (b)  Hall, 
The  Soil. 

GARDENING  FOR  SCHOOLS. — (a)  Hennesey,  The  School  Garden,  is.  (b)  Jones, 
Plant  Life :  Studies  in  Garden  and  School.  35.  6d.  (c)  Rankin,  School  Gardening. 
is.  6d.  (d)  Weathers,  Guide  to  School,  Cottage,  and  Allotment  Gardening.  2s.  6d. 

(c)  United  States  Bureau  of  Education  :  School  Gardens.     (/)  Board  of  Educa- 
tion, Educational  Pamphlets  :  The  Education  of  the  Cottage  Gardener  (Dymond). 


THE    WORK    OF    THE    SOIL 

BY  A.  D.  HALL,  M.A.,  F.R.S., 

Director  of  the  Experimental  Station  at  Rothamsted. 

CHAPTER  XIII 

THE  ORIGIN  OF  SOILS 

IN  order  to  understand  how  the  soil  has  come  into  being  it  is 
desirable  to  find  some  comparatively  fresh  excavation,  like  a  stone 
quarry,  preferably  one  situated  a  little  way  up  the  sloping  side 
of  a  valley,  so  that  the  layer  of  soil  covering  the  rock  may  not  be 
too  deep.  The  rock  exposed  in  the  quarry  may  be  road  stone, 
building  stone,  chalk,  or  even  nothing  more  than  hard  clay  or 
sand, — in  any  case,  much  the  same  sequence  will  be  visible.  At 
the  bottom  of  the  quarry  will  be  seen  the  native  rock,  showing, 
except  in  such  cases  as  basalt  or  granite,  a  distinct  bedded  struc- 
ture of  layer  superimposed  upon  layer,  often  varying  in  colour  or 
hardness  from  band  to  band.  Nearer  the  surface  the  structure 
of  the  rock,  whether  massive  or  bedded,  begins  to  fail ;  fractures 
become  common  until  the  layers  consist  of  loose  stones,  though 
they  are  still  lying  in  the  positions  they  occupied  before  the 
breaking  up  took  place.  A  little  higher  the  stones  become  smaller 
and  are  separated  by  intervals  filled  with  loose  disintegrated 
rock,  often  a  mere  coarse  sand;  higher  still,  the  loose  material 
is  greater  in  amount  than  the  stones,  which  now  lie  scattered 
about  in  what  fairly  may  be  termed  soil,  since  all  the  structure  of 
the  underlying  rock  has  disappeared.  Nearer  the  surface,  again, 
the  soil  gains  still  more  on  the  stones,  which  in  some  cases  dis- 
appear entirely ;  finally,  at  the  top,  there  is  a  darker  layer,  six 
inches  to  a  foot  or  more  in  thickness,  which  constitutes  the  soil 
proper  as  distinct  from  the  subsoil,  this  name  being  given  to  the 
fine  material  below. 


A   QUARRY   IN   THE   HYTHE   BEDS    (Lower   Greensand) 

Showing  the  passage  of  hard  calcareous  rock  into  soil. 
A  sedentary  soil  (/.  188) 

(From  the  author's  book,   The  Soil,  published  by  John  Murray) 


THE  ORIGIN  OF  SOILS  189 

As  a  rule  certain  changes  of  colour  accompany  the  passage 
from  rock  into  soil  that  has  just  been  described  ;  not  infrequently 
the  rock  possesses  some  shade  of  dark  olive  green  or  grey  or  black, 
and  only  begins  to  show  yellow  or  brown  stains  and  rusty  marks 
along  the  fractures  at  a  higher  level ;  the  fine  broken-down  rock, 
which  gradually  becomes  the  subsoil,  is  nearly  always  of  an  ochre 
colour — yellow,  brown,  or  red — which  becomes  darker  or  duller  as 
it  passes  into  the  soil.  According  to  the  nature  and  situation  of 
the  rock,  the  transition  just  described  may  extend  over  as  much  as 
twenty  feet,  or  may  be  complete  in  two  or  three  ;  indeed,  on  the  high 
downs  hard  unbroken  chalk  may  be  found  only  a  foot  below  the 
surface,  and  soil  and  subsoil  together  may  not  be  more  than  six 
inches  thick.  The  important  feature  is  that  the  rock  passes  by  in- 
sensible gradations  into  the  soil,  and  that  no  sharp  line  of  separa- 
tion can  be  drawn  at  any  point  in  the  passage.  Not  infrequently, 
however,  a  different  sequence  may  be  observed  :  the  rock  surface 
ends  abruptly  without  any  of  the  breaking  up  described  above ; 
instead,  it  is  overlaid  by  a  bed  of  clay  or  sand  or  gravel  of  entirely 
different  character,  which  in  its  turn  passes  by  insensible  degrees 
into  the  soil.  Leaving  such  cases  alone  for  the  present,  the 
quarry  merits  further  examination  to  ascertain  by  what  agencies 
the  change  from  rock  into  subsoil  and  soil  has  been  effected. 

If  the  weather  has  not  been  dry  for  too  long  a  period  it  will  be 
seen  that  even  the  hardest  and  most  uniform  rock  near  the  base 
of  the  quarry  is  still  traversed  by  a  number  of  up-and-down  cracks, 
the  "  joints  "  of  the  stone,  and  that  water  works  along  these 
joints,  as  their  discoloured  edges  demonstrate.  Higher  up  the 
joint  cracks  become  more  numerous  and  a  little  wider,  the  edges 
are  also  somewhat  rounded,  as  though  the  water  oozing  along 
them  had  softened  and  removed  a  little  of  the  sides  ;  moreover, 
down  some  of  them  fine  roots  of  trees  and  other  strong  growing 
plants  will  be  found  to  have  wandered.  As  these  roots  are  traced 
upwards  they  become  thicker,  and  evidently  exert  a  certain  amount 
of  pressure  outwards,  thus  widening  the  crack  and  bursting  the 
stone. 

The  mechanical  effect  of  the  roots  is  obvious  enough,  that  of 
the  water  is  rather  more  subtle  ;  in  some  cases  the  water  will 
appear  to  have  dissolved  away  the  cement  which  binds  together 


igo  THE  BOOK  OF  NATURE  STUDY 

the  grains  of  sand  making  up  the  original  sandstone  rock.  Other 
rocks,  the  basalts  and  granites,  for  example,  under  the  influence 
of  water,  simply  grow  rotten,  like  an  old  exposed  piece  of  iron 
covered  with  layer  after  layer  of  rust ;  they  pass  by  insensible 
gradations  into  clay,  whereas  limestones  keep  a  firm  surface  but 
seem  to  have  largely  melted  away  into  thin  layers  of  sticky  clay. 

Here,  then,  are  two  of  the  agents  making  soil  out  of  rock 
— roots  to  burst,  water  to  rot  and  dissolve  ;  the  work  of  a  third 
great  agent — frost — will  be  most  in  evidence  if  an  old  face  of  the 
quarry  be  examined  just  after  a  thaw.  Failing  that  a  visit  may 
be  paid  to  an  old  brick  or  stone  wall,  especially  one  backing  against 
a  bank  that  will  keep  plenty  of  moisture  in  the  wall.  After  the 
frost  has  departed  the  ground  at  the  foot  of  the  quarry  face  or  the 
wall  will  be  covered  with  fragments  of  stone  or  brick  which  have 
obviously  only  just  fallen  away  from  the  clean  broken  faces  above. 
It  is  easy  to  show,  by  tightly  tying  in  the  cork  of  a  bottle  filled 
with  water  and  exposing  it  in  a  frosty  night,  that  water  expands 
considerably  in  the  act  of  turning  into  ice ;  and  further,  that  it 
exerts  a  pressure  on  whatever  resists  this  expansion  such  as  very 
few  materials  can  withstand.  The  stones  or  bricks  of  the  wall, 
and  even  the  stones  a  little  below  the  surface  of  the  ground,  are 
generally  saturated  with  water;  they  become  rent  open  as  the 
water  expands  on  freezing  and  fall  in  pieces  as  it  thaws  again. 
Thus  the  expansion  of  water  on  freezing  must  be  added  to  its  dis- 
solving and  rotting  powers  as  one  of  the  agencies  reducing  rocks 
to  soil,  although,  since  frost  in  this  country  rarely  penetrates  the 
ground  to  a  greater  depth  than  a  foot  or  eighteen  inches,  it  is  in 
the  upper  layers,  the  soil,  that  its  disintegrating  action  is  most  felt. 
These  agencies — roots,  water,  and  ice — may  at  first  sight  appear  too 
slow  and  trivial  to  have  been  capable  of  forming  four  or  five  feet  of 
soil  and  perhaps  ten  or  twelve  feet  of  rotten  stone,  but  it  is  only 
necessary  to  look  at  an  old  castle  or  unrestored  church  to  realise 
how  active  the  "  tooth  of  time  "  can  be.  Five  hundred  years 
carves  into  the  most  fantastic  shapes  the  face  of  even  the  hardest 
building  stones,  stones  which  have  been  kept  comparatively  dry  by 
exposure  instead  of  being  buried  in  the  wet  ground,  where  also 
roots  are  at  work.  Yet  many  periods  of  five  hundred  years  have 
elapsed  since  our  present  layer  of  soil  began  to  be  made,  since  the 


THE  ORIGIN  OF  SOILS  191 

land  surface  upon  which  we  now  live  either  emerged  from  the  sea 
or  was  left  as  naked  rock  on  the  melting  of  its  last  covering  of 
glacial  ice.  As  a  matter  of  fact,  the  soil  covering  we  see  on  the 
side  of  the  hill  is  only  a  fraction  of  that  which  has  been  formed 
from  the  rock,  because  the  soil  is  always  creeping  down  the  hill- 
side and  being  washed  away  by  the  river  below.  In  time  of 
heavy  rain  this  is  obvious  enough,  every  little  drainage  gulley 
in  the  fields,  each  spring  and  streamlet  well  above  the  main 
river,  are  charged  with  turbid  water ;  the  river  itself  is  not  only 
heavily  laden  with  sediment  washed  from  the  land,  but  is  pushing 
along  its  bed  sand  and  gravel  and  even  stones  of  considerable  size. 
The  broad  truth  that  rivers  have  carved  out  their  own  valleys, 
and  that  the  material  they  remove  is  not  rubbed  off  the  solid 
rock,  but  is  the  soil  into  which  the  rock  has  first  of  all  passed 
by  the  action  of  the  weather,  itself  indicates  that  the  soil-making 
process  must  have  been  a  far  greater  one  than  can  be  measured 
by  the  amount  of  soil  actually  existing  to-day. 

Having  thus  seen  that  in  times  of  heavy  rain  a  great  deal  of 
the  soil  which  had  been  previously  formed  gets  washed  into  the 
rivers,  it  is  instructive  to  collect  some  of  this  rapidly  flowing 
turbid  water  and  let  it  settle  down  in  a  clear  glass  in  order  to 
get  an  idea  of  the  nature  and  amount  of  the  sediment  that  is  being 
transported.  In  most  cases,  when  the  water  is  drawn  from  a  fair 
sized  river  in  not  too  violent  a  state  of  flood,  the  material  will 
take  some  days  to  settle  down,  and  will  then  form  a  sticky  deposit, 
which,  however,  is  not  wholly  clay,  because  it  feels  a  little  gritty 
when  rubbed  between  the  fingers.  It  consists,  in  fact,  of  the  finest 
particles  of  the  soil ;  the  stones,  the  gravel,  and  even  the  coarser 
sand  have  been  left  behind  or  are  being  pushed  more  slowly  along 
the  river  bed.  It  will  be  dark  coloured,  because  it  has  been  chiefly 
washed  off  the  surface  layer  of  the  soil  containing  vegetable  matter, 
and  if  it  is  dried  and  heated  in  an  open  dish  the  presence  of  this 
vegetable  matter  will  become  evident  by  the  charring  smell. 

As  to  the  fate  of  this  solid  matter  suspended  in  the  fast 
running  water,  there  can  be  but  little  doubt :  much  of  it  evidently 
finds  its  way  down  into  the  sea,  and  is  there  deposited  as  the 
mud  flats,  sand  banks,  and  shoals  which  impede  the  mouth  of 
many  of  our  rivers.  If  the  tides  and  currents  off  the  mouth  of 


192  THE  BOOK  OF  NATURE  STUDY 

the  river  are  not  such  as  will  shift  the  deposit  into  deeper  waters, 
the  material  gradually  accumulates  and  forms  new  land,  so  that 
the  river  mouth  is  always  moving  seaward.  Along  the  Channel 
and  on  the  east  coast  of  England,  most  noticeably  in  the  Wash, 
the  land  is  always  steadily  gaining  on  the  sea  by  means  of  the 
detritus  washed  down  by  the  rivers. 

Some  of  the  material,  however,  does  not  reach  the  sea,  but 
accumulates  along  the  river  course  ;  nearly  all  rivers,  as  soon  as 
their  early  mountainous  rush  is  over,  will  be  found  flowing  quietly 
between  broad  level  meadows,  which  are  apt  to  be  covered  from 
time  to  time  with  flood  water.  On  examining  the  soil  beneath 
one  of  these  meadows  it  will  be  found  to  be  practically  identical 
with  the  silt  deposit  which  had  previously  settled  out  from  the 
glassful  of  turbid  river  water.  Careful  examination  of  the 
meadow  will  also  as  a  rule  show  that  its  level  rises  very  slightly 
towards  the  water's  edge,  the  actual  river  bank  being  generally 
elevated  a  few  feet  farther.  In  consequence,  when  a  flood  occurs 
and  the  turbid  flood  water  invades  the  meadows,  it  is  there  some- 
what pounded  up,  and  does  not  simply  flow  back  into  the  river 
when  its  level  falls.  Instead  the  flood  water  sinks  through  the 
soil  or  oozes  back  under  ground  into  the  river  bed ;  but  in  so  doing 
it  leaves  behind  on  the  surface  of  the  meadow  the  load  of  silt  it 
was  carrying  before.  After  a  flood  has  subsided  the  grass  of  the 
river  meadows  will  be  found  all  sticky  and  muddy,  and  the  whole 
surface  of  the  meadow  has  really  been  raised  to  a  very  small  extent 
by  the  deposit  left  behind.  Thin  as  the  layer  may  seem,  the  whole 
soil  below  the  water  meadow  has  been  deposited  in  this  way  ; 
it  is  made  up  of  earth  washed  down  from  some  district  higher  up 
the  river's  course,  flood  after  flood  it  has  grown  and  thickened 
until  it  has  gradually  spread  across  the  valley.  The  river  may 
still  be  seen  cutting  away  its  banks  in  places  and  removing  what  it 
has  previously  deposited,  but  provided  that  the  slope  of  the  valley 
is  getting  flatter  so  that  the  river  is  decreasing  in  velocity  as  it 
gets  nearer  the  sea,  it  will  always  be  leaving  behind  more  than  it 
takes  away  and  gradually  increasing  the  thickness  of  the  soil  over 
the  stretch  of  meadows.  Because  the  river  sediment,  however,  has 
been  derived  from  rocks  higher  up  in  the  valley,  and  because  it  has 
been  subjected  to  a  certain  amount  of  sorting  by  the  running  water, 


A  QUARRY  IX  CHARXWOOD  FOREST  SHOWING  GLACIAL  DRIFT,  A,  RESTIXG 

OX  NEW  RED  SAXDSTOXE,  B,  WHICH  ITSELF  RESTS  UPON 

AN  OLD  SYENITE,  C 

The  soil  is  derived  from  the  glacial  drift.     A  soil  of  transport  (p.  193). 


THE  ORIGIN  OF  SOILS  193 

the  coarser  particles  being  carried  only  by  the  swifter  streams  and 
dropped  as  soon  as  the  velocity  falls,  it  is  probable  that  it  will 
not  resemble  the  soil  we  have  already  examined  on  the  flanks  of 
the  valley,  a  soil  which  had  grown  out  of  the  rock  beneath  it. 
There  is  bed  rock  beneath  the  river  meadow  soil  if  we  cut  down 
deep  enough,  but  when  we  do  find  the  point  of  junction  the  change 
from  the  rock  to  soil  is  clear  and  sharp,  for  the  river  silt  has  been 
deposited  on  a  clean  rock  surface,  usually  of  an  entirely  different 
character.  We  are  now  dealing  with  one  of  the  cases  alluded 
to  before,  where  the  soil  has  not  grown  out  of  the  rock  beneath  it, 
but  has  been  carried  from  a  distance  and  deposited  by  water  or 
some  kindred  agency,  giving  rise  to  a  "  soil  of  transport "  or 
"  drift  soil,"  as  it  is  termed,  to  distinguish  it  from  the  "  seden- 
tary "  soil  which  has  been  formed  where  it  lies.  A  soil  of  trans- 
port may  be  similar  to  the  rock  below  it  if  it  happens  to  have 
been  originally  derived  from  another  area  of  similar  rock,  or  it 
may  be  entirely  different — as  a  rule  the  change  from  rock  into 
soil  is  sharp  and  distinct.  A  soil  of  transport  is  usually  further 
distinguishable  by  its  uniform  character ;  as  one  descends  there 
is  no  increase  in  the  number  of  the  larger  fragments  of  rock, 
etc.,  which  characterise  the  lower  depths  of  a  sedentary  soil. 
River  meadow  soils,  indeed,  are  much  of  a  type  all  over  the 
country ;  they  are  a  little  lighter  or  a  little  heavier  according 
to  the  nature  of  the  rocks  in  the  river  basin,  and  they  vary 
in  their  behaviour  towards  crops  with  the  depth  of  the  water 
and  the  existence  or  not  of  a  bed  of  gravel  below  the  surface  ; 
they  are  classed  generally  as  alluvial  soils.  On  the  flanks  of  the 
valley,  above  the  present  alluvial  level,  areas  more  or  less  extensive 
are  often  seen,  covered  with  sand  or  gravel  or  brick  earth,  which 
have  obviously  been  originally  water-borne  into  their  present  posi- 
tion; these  are  the  remains  of  old  alluvial  deposits  which  formerly 
filled  the  valleys,  but  have  been  very  largely  removed  through 
certain  geographical  or  climatic  changes  that  have  altered  the 
rainfall  and  so  caused  a  newer  valley  to  be  carved  out  of  the  old 
alluvian.  Again,  over  great  parts  of  the  north  and  midlands  of 
England  the  surface  of  the  country  is  covered  with  deposits,  often 
of  great  thickness,  which  have  been  transported  by  moving  ice 
during  the  last  glacial  epoch  ;  it  depends  rather  upon  the  thickness 

VOL.  V. — 13 


I94  THE  BOOK  OF  NATURE  STUDY 

and  uniformity  of  the  glacial  deposit  whether  the  soils  formed 
from  them  shall  be  termed  sedentary  or  soils  of  transport.  Other 
true  "soils  of  transport "  are  wind  borne,  though  almost  the  only 
examples  we  see  of  them  in  this  country  are  the  soils  that  have 
grown  up  on  the  inland  side  of  the  tracts  of  sand-dunes  which  border 
some  parts  of  the  coast.  A  peat  bog,  though  entirely  unlike  the 
strata  upon  which  it  may  be  resting,  has  yet  been  formed  in  situ, 
and  must  be  classified  as  sedentary.  The  causes  which  lead  to  such 
a  formation  will  be  considered  later. 

It  is,  in  fact,  impossible  to  draw  any  entirely  satisfactory  line 
of  distinction,  for  soils,  however  sedentary  they  may  be  in  their 
origin,  are  always  in  motion,  and  often  in  the  end  acquire  the 
character  of  soils  of  transport.  As  an  example  it  is  instructive  to 
compare  two  neighbouring  fields,  one  arable  and  the  other  old 
pasture,  on  any  soil  where  stones  are  abundant,  as,  for  example, 
on  the  chalky  soils  of  the  south  and  east  of  England  or  the  boulder 
clayland  of  the  north  and  midlands.  The  arable  land  will  be 
seen  to  be  covered  with  stones,  and  even  if  they  have  been  worth 
picking  off  they  are  as  abundant  as  ever  soon  afterwards,  until 
the  old  farmers  aver  that  they  "grow."  In  reality,  the  soil 
is  being  constantly  stirred  by  the  plough,  and  as  the  soil 
settles  down  again  the  washing  rains  carry  down  the  fine 
particles  and  leave  on  the  top  the  stones  they  cannot  move. 
You  have  only  to  look  at  some  spot  where  a  water  pipe  drips 
on  to  a  bed  of  bare  soil  to  understand  how  on  arable  land  the 
stones  are  always  working  to  the  surface. 

On  the  old  pasture  alongside  not  a  stone  is  to  be  seen,  and  if  a 
trench  be  cut,  the  surface  soil  of  the  pasture  will  be  found  to  be 
fine  mould  free  from  stones,  down  to  a  depth  depending  upon  the 
age  of  the  pasture.  Yet  the  arable  land  and  the  pasture  started 
alike,  it  is  the  action  of  the  earthworms  that  has  gradually  brought 
the  stones  below  the  surface  of  the  pasture  land.  Earthworms  are 
always  at  work  bringing  up  fine  soil  from  below  and  ejecting  it  in 
the  form  of  worm-casts  on  the  top  of  the  present  surface,  and 
small  as  the  amounts  brought  up  may  seem  to  be,  the  action  is 
yet  so  continuous  that  when  the  casts  are  spread  over  the  surface 
the  layer  raised  each  year  possesses  a  measurable  thickness.  In 
this  way  stones  and  any  other  objects  lying  on  the  surface  of 


THE  PROPERTIES  OF  SOILS  195 

grassland  gradually  come  to  be  buried ;  year  by  year  they  get 
deeper  as  the  fine  earth  is  carried  up  from  beneath  them  and 
deposited  above,  until  at  last  they  reach  the  depth  below  which 
the  worms  do  not  work.  The  reality  of  this  burying  action,  and 
even  the  rate  at  which  it  takes  place,  can  often  be  detected  on  an 
old  pasture  or  a  lawn  by  opening  a  trench;  at  a  slight  depth 
may  be  seen  a  thin  layer  of  chalk  or  cinders  which  represents  an 
application  of  lime  or  ashes  to  the  surface  of  the  grassland  some 
years  previously.  If  the  date  of  this  application  has  been  re- 
corded it  is  easy  to  calculate  the  rate  at  which  it  has  been  sinking, 
or  rather,  at  which  it  has  been  buried  by  the  action  of  the  earth- 
worms ;  in  this  way  Darwin  was  able  to  show  that  in  one  case 
materials  had  sunk  three  inches  in  fifteen  years,  and  in  another, 
seven  inches  in  twenty-nine  years. 

THE  PROPERTIES  OF  SOILS. 

In  order  to  arrive  at  a  proper  understanding  of  the  nature 
and  behaviour  of  different  kinds  of  soil  in  the  field  it  is  now 
necessary  to  do  a  few  simple  experiments,  experiments  which 
do  not  call  for  any  elaborate  apparatus,  but  which  become 
particularly  instructive  if  they  are  made  quantitative  by  the 
use  of  a  balance  and  some  of  the  more  common  accessories 
of  a  laboratory.  In  the  first  place,  it  will  be  necessary  to 
collect  a  few  specimens  of  soil  by  making  a  hole  so  as  to 
lay  bare  a  face  of  the  soil,  and  then  taking  out  with  a  trowel 
vertical  slices,  nine  inches  deep  for  the  soil,  and  from  ten  to 
eighteen  inches  for  the  subsoil,  until  two  or  three  pounds  have  been 
collected.  Samples  are  wanted  from  an  alluvial  meadow  (soil 
and  subsoil),  from  heavy  clay  and  light  sandy  arable  land  (soil 
and  subsoil),  from  peaty  land  (soil  only).  The  soils  should  be 
spread  out  on  sheets  of  brown  paper  and  left  to  dry  naturally  in  a 
room ;  they  should  be  turned  from  time  to  time  and  crumbled 
between  the  fingers  when  they  are  just  beginning  to  dry, — there 
is  a  certain  stage  in  the  drying  of  a  clay  soil  when  it  can  be  easily 
reduced  to  a  powder,  a  process  which  is  a  matter  of  some  difficulty 
if  the  soil  is  once  allowed  to  get  thoroughly  dry.  The  soils  can 
then  be  stored  away  in  bottles  or  tins.  There  will  now  be  wanted 


196  THE  BOOK  OF  NATURE  STUDY 

a  balance,  a  beaker  or  two,  a  pestle  made  by  sticking  a  small 
rubber  bung  on  the  end  of  a  glass  rod,  and  two  sieves,  the  first 
of  the  finest  woven  brass  wire,  100  meshes  to  the  inch,  and  the 
other  made  by  cutting  out  a  square  from  the  bottom  of  a  tin 
box  and  replacing  it  by  soldering  on  a  piece  of  perforated  zinc 
with  holes  A-  of  an  inch  ( =  i  mm.)  in  diameter. 

Throw  the  soil  on  to  this  sieve,  and  when  you  have  shaken  as 
much  as  possible  of  the  fine  earth  through  put  the  sieve  under 
the  tap  and  let  the  water  drip  on  its  contents,  which  will  be 
the  stones  contained  in  the  soil  together  with  a  good  many 
hard  lumps  of  earth,  especially  with  a  clay  soil.  However, 
these  will  break  up  in  the  water  and  after  a  little  shaking  under 
the  tap  will  wash  away  and  leave  behind  the  clean  stones  and 
fine  gravel  more  than  i  mm.  in  diameter,  together  with  a 
few  fragments  of  roots  and  vegetation.  The  stones  and  gravel 
should  be  dried  and  examined  to  see  what  they  are  made  of, 
whether  they  are  water  worn  or  angular,  etc. ;  we  can  also  take 
their  weight  and  find  what  proportion  they  constitute  of  the 
original  soil,  though  the  results  will  not  mean  very  much  when 
the  soil  contains  large  stones. 

From  the  fine  earth  that  passed  the  sieve,  five  grams  are  now 
weighed  out  and  put  into  a  beaker  on  the  side  of  which  you  have 
made  a  mark  three  inches  from  the  bottom.  Add  a  little  water  to 
the  soil  and  churn  it  up  into  a  smooth  thin  paste  with  the  rubber 
pestle,  add  more  water  until  the  beaker  is  full  to  the  mark  ;  give  a 
good  stir  and  let  the  contents  settle  for  one  minute  exactly,  then 
pour  the  muddy  water  steadily  and  quickly  into  a  jar  without 
disturbing  the  sediment  collected  at  the  bottom  of  the  beaker. 
Churn  up  again  with  the  pestle,  fill  to  the  mark  with  water  as 
before,  and  again  wait  one  minute  before  pouring  off  the  turbid 
top  liquid.  Repeat  these  operations  until  the  top  liquid  becomes 
clear  during  the  minute's  wait,  because  the  only  material  now 
left  in  the  beaker  is  so  coarse  grained  that  it  will  fall  to  the  bottom 
in  less  than  a  minute.  It  will  now  be  seen  that  by  this  process 
the  soil  has  been  separated  into  clean  sand  that  lies  in  the  beaker 
and  finer  clay  like  stuff  which  has  been  poured  away  in  the  turbid 
top  liquid.  Keep  a  j  ar  full  of  this  turbid  water  for  a  few  days ;  it  will 
settle  down  very  slowly,  but  when  it  does  clear  pour  off  as  much 


THE  PROPERTIES  OF  SOILS  197 

of  the  water  as  possible  and  examine  the  layer  at  the  bottom. 
It  will  be  found  to  be  scarcely  gritty,  but  almost  greasy  to  the  touch, 
indicating  that  it  is  made  of  very  fine  particles  ;  on  drying  it  will 
shrink  and  crack  and  form  a  hard  cake.  Now  take  the  beaker 
with  the  sand  in  it,  put  it  in  the  oven,  and  when  it  is  dry  brush 
out  the  sand  (it  will  be  quite  loose  and  show  no  tendency  to 
cake)  on  to  the  fine  sieve,  and  weigh  the  two  portions,  the 
coarse  sand  which  is  retained  and  the  fine  sand  which  passes 
through.  Now  tabulate  the  results  : — 

5  grams  taken =  100  per  cent. 

Coarse  sand,  0*23  grams  .  .  =  4-6  „ 
Fine  sand,  3*61  grams  .  .  =  72*2  „ 
Clay  and  silt  (by  difference)  =  23*2  „ 

Repeat  this  experiment  for  both  soil  and  subsoil  of  the  clay  and 
sandy  arable  land,  and  set  out  all  the  results  side  by  side. 

The  process  just  described  is  a  rough  version  of  the  accepted 
method  of  analysing  a  soil  mechanically  by  grading  it  into  its 
constituent  particles  of  clay  and  sand  of  various  sizes.  If  even  the 
simple  appliances  required  are  not  available,  a  good  deal  of  infor- 
mation can  be  got  by  adding  a  spoonful  of  each  of  the  powdered 
soils  to  separate  tea-cups,  rubbing  them  up  with  water  as  de- 
scribed and  pouring  off  the  turbid  water,  using  the  finger  as  a 
pestle,  and  finally  collecting  the  sand  remaining  at  the  bottoms  of 
each  cup  on  separate  sheets  of  paper  for  comparison  by  the  eye. 

On  examining  the  results  it  will  be  seen  that  the  sandy  soil  is 
not  all  sand,  but  that  a  fair  amount  of  clay  and  fine  silt  can  be 
washed  away  from  it,  also  that  the  clay  soil  often  contains  a 
considerable  proportion  of  fine  sand.  We  never  find  a  purely 
clay  soil,  and  only  on  the  most  barren  of  heaths  will  the  sandy 
soils  contain  less  than  10  per  cent,  of  clay  and  silt.  Next,  we 
shall  see  that  the  sandy  soil  and  its  subsoil  are  much  alike  as 
regards  the  proportion  of  sand  and  clay  they  contain,  but  that 
the  surface  layer  of  the  clay  soil  is  distinctly  more  coarsely 
grained  and  contains  a  higher  proportion  of  sand  than  the  sub- 
soil. This  difference  between  soil  and  subsoil  is  due  to  the  rain 
washing  away  the  finest  particles  and  leaving  the  coarser  ones 
behind,  just  as  we  have  seen  the  flint  stones  are  left  on  the  top 


198  THE  BOOK  OF  NATURE  STUDY 

of  an  arable  field ;  the  difference  is  less  seen  in  the  sandy  soil, 
because  it  contains  so  little  of  the  very  finest  stuff  that  can  wash 
through  the  soil. 

By  repeating  such  experiments  on  a  variety  of  soils  we 
may  learn  that  they  all  consist  fundamentally  of  mixtures  of 
clay  and  sand  of  various  grades  ;  in  clays  and  heavy  soils  the 
finest  particles  predominate  and  there  is  very  little  coarse  sand 
to  keep  the  soil  open ;  in  the  really  barren  sands  the  coarse  sand 
predominates,  but  there  are  many  sandy  soils,  made  up,  however, 
of  the  finest  grades  of  sand,  which  are  fertile  enough.  What  a 
farmer  calls  a  good  free  working  loam  is  generally  found  to  consist 
of  a  well  balanced  mixture  of  the  finer  grades  of  sand,  bound  to- 
gether by  clay  and  kept  open  by  a  sufficiency  of  coarse  particles. 

Having  thus  learned  something  of  the  constitution  of  soils,  it 
becomes  possible  to  begin  to  interpret  their  behaviour  towards 
water.  Take  five  ordinary  glass  funnels,  fit  them  with  filter 
papers  or  plug  them  with  a  little  cotton  wool,  and  pack  on  to 
four  of  them  fifty  grams  each  of  the  dry  powdered  sandy,  clay, 
peaty,  and  alluvial  soils  respectively.  Pour  on  to  each  an 
equal  volume  of  water,  one  hundred  cubic  centimetres  will  serve, 
and  catch  in  beakers  the  water  that  runs  through  ;  note  the 
time  taken,  and  the  amount  passing  through  in  each  case.  In 
the  fifth  funnel  take  another  fifty  grams  of  clay  soil,  but  work 
it  up  into  a  paste  with  a  little  of  the  100  c.c.  of  water  before 
putting  it  on  the  filter,  and  then  add  the  rest  of  the  water. 
The  peat  and  clay  soils  retain  the  most  water,  the  alluvial  soil 
coming  between  them  and  the  sand;  the  percolation  will  be 
slowest  with  the  clay  soil,  while  it  will  hardly  take  place  at 
all  with  the  clay  that  had  been  first  of  all  pulped  up  in  a  wet 
condition.  This  shows  how  the  rain  falling  on  a  sandy  soil 
finds  its  way  downwards  very  quickly,  little  being  retained 
by  the  soil  for  the  needs  of  the  plant,  so  that  a  light  sandy 
soil  easily  suffers  from  drought ;  it  also  shows  how  a  peaty 
soil  retains  a  great  deal  of  water  while  allowing  the  excess 
to  move  through  it  pretty  quickly.  On  a  clay  soil,  however, 
because  it  is  made  up  of  very  fine  particles,  both  a  large  pro- 
portion of  water  is  retained  and  the  movements  through  the  soil 
are  very  slow  ;  moreover,  the  slowness  of  percolation  is  enormously 


THE  PROPERTIES  OF  SOILS  199 

increased  if  all  the  little  clusters  of  fine  particles,  which  gradually 
form  in  clay  by  the  action  of  the  weather,  etc.,  are  first  of  all 
broken  up  by  kneading  the  soil  in  a  wet  state.  The  amount  of 
water  retained  by  a  soil  depends  upon  the  extent  of  the  surface  of 
the  particles  that  get  wetted,  and  for  an  equal  weight  of  matter 
the  finer  the  grains  are  the  greater  will  be  their  total  surface. 

But  percolation  downwards  is  not  the  only  motion  of  the  soil 
water  ;  it  is  able  also  to  move  upwards  in  the  same  way  as  it  will 
gradually  wet  the  whole  of  a  towel  of  which  only  the  extreme 
end  is  actually  dipping  into  water.  To  illustrate  this  action, 
separate  by  means  of  the  fine  sieve  some  sand  into  fine  and 
coarse  particles  respectively ;  take  four  wide  glass  tubes  eighteen 
inches  or  two  feet  long,  tie  a  little  fine  muslin  over  the  bottom 
or  plug  them  with  cotton  wool  and  fill  them  with  the  coarse 
and  fine  sand,  the  alluvial  and  the  clay  soil  respectively. 
Then  stand  the  muslin-covered  ends  an  inch  deep  in  water, 
and  note  hour  by  hour  the  extent  to  which  water  has  risen  in 
each,  finally  plotting  the  results  on  a  piece  of  squared  paper. 
The  motion  is  much  quicker  in  the  sand  than  in  the  clay,  but 
in  the  coarse  sand  it  extends  only  for  a  few  inches.  In  the 
fine  sand  the  water  rises  much  farther,  while  in  the  clay,  slow 
as  the  motion  is,  it  will  continue  until  the  whole  contents  of  the 
tube  are  wet.  Now  these  observations  can  be  applied  to  the 
study  of  soils  ;  at  some  depth  below  the  surface  there  is  always 
a  layer  saturated  with  water,  the  level,  in  fact,  at  which  water 
stands  in  the  wells  sunk  thereabouts,  and  even  when  this  "  water 
table  "  is  at  some  considerable  depth  the  subsoil  a  few  feet  down 
is  none  the  less  highly  charged  with  water.  During  a  drought, 
as  the  surface  soil  loses  its  moisture,  the  water  will  begin  to  rise 
from  the  wet  layers  below  in  virtue  of  the  property  of  capillarity 
or  surface  tension  that  we  have  just  illustrated.  When  the  soil 
is  damp  each  particle  is  surrounded  by  a  thin  film  of  water  in  a 
state  of  tension,  so  that  it  exerts  a  pull  on  other  water  with 
which  it  may  be  in  contact,  the  pull  being  greater  the  thinner 
and  more  stretched  the  film  may  be.  Hence  a  particle  with  a 
thin  film  will  draw  water  from  a  thicker  film  which  it  touches. 
As  long  as  the  thin  films  of  water  coating  the  soil  particles 
remain  continuous  and  unbroken,  water  will  always  creep  from 


200 


THE  BOOK  OF  NATURE  STUDY 


wetter  to  drier  places,  whether  the  motion  has  to  be  directed 
upwards,  downwards,  or  sideways.  And  the  greater  the  surface 
exposed,  as  in  the  fine  grained  soils,  the  greater  will  be  the 
water-moving  power ;  but  when  the  particles  are  very  small 
indeed,  as  in  a  clay  soil,  the  rate  of  motion  becomes  extremely 
slow,  because  of  the  friction  of  the  water  moving  between  the 
very  fine  grained  particles.  It  is  this  capillary  power  in  soils 
which  keeps  plants  growing  during  a  drought ;  they  would 
quickly  use  up  all  the  water  which  the  soil  immediately  round 
the  roots  had  retained  were  not  the  surface  soil  constantly 


C.M. 
40 

FINE  SAND 

•  

• 

30 

: 

^—-' 

— 



^  g  ••  •" 

20 

/ 

^ 

LOAM   „ 

,,  " 

ID 

,'* 

COARSE  SAM 

*  *•** 

^—— 

CLAY 
^—  

^-—  

-  —  

0 

L---  1 

^—  —  ' 

2  456  HOURS 

FIG.  77.— Rate  of  rise  of  water  in  different  soils,  due  to  capillarity  or  surface  tension. 

lifting  water  from  the  wetter  layers  below.  Sandy  soils  suffer 
badly  from  drought,  because  both  water  retaining  power  and 
capillary  lifting  power  are  low  ;  clay  soils  can  stand  a  short 
drought  because  they  retain  so  much  water,  but  when  this  is 
exhausted  they  can  only  renew  their  supplies  very  slowly,  and 
also  begin  to  lose  further  by  the  big  cracks  that  form.  The 
best  soils  for  keeping  crops  growing  during  drought  are  loams 
mainly  composed  of  very  fine  sand ;  their  water-retaining  power 
may  not  be  high,  but  the  particles  possess  sufficient  surface  to 
lift  water  rapidly,  and  yet  are  not  so  small  as  to  offer  resistance 
to  its  movement. 


THE  PROPERTIES  OF  SOILS  201 

For  the  next  experiment  procure  a  piece  of  good  clay  ;  failing 
any  in  the  neighbourhood,  buy  a  few  pounds  of  modelling  clay. 
Knead  a  piece  up  and  beat  it  into  a  little  brick  an  inch  or  so 
square  in  section  and  about  five  inches  long,  mark  two  points 
on  the  surface  exactly  ten  centimetres  apart,  and  put  the  brick 
aside  in  a  warm  place  to  dry.  Make  up  a  second  brick,  but  before 
you  knead  up  the  clay  incorporate  with  it  as  fully  as  possible  a  few 
cubic  centimetres  of  milk  of  lime,  again  mark  off  a  length  of  ten 
centimetres  on  the  surface.  Moisten  some  of  the  clay  soil  used  in 
the  previous  experiments  by  adding  overnight  about  20  per 
cent,  of  its  weight  of  water,  and  with  it  build  up  another  brick, 
this  time  knocking  the  clay  about  as  little  as  may  be  consistent 
with  pressing  it  firmly  together  into  brick  form.  When  the 
three  bricks  have  dried  it  will  be  found  from  the  relative  position 
of  the  marks  that  they  have  all  shrunk  considerably,  the  raw  well 
kneaded  clay  most  of  all.  Then  compare  the  hardness  of  the 
three  bricks  by  breaking  them  between  the  fingers  ;  the  soil 
breaks  and  crumbles  without  much  difficulty,  whereas  the  clay 
proper  is  extremely  hard  and  tough,  though  the  tenacity  of  that 
which  had  been  worked  up  with  lime  has  been  much  reduced. 
These  then  are  essential  properties  of  clay, — shrinkage  on  drying 
and  tenacity  of  the  dried  mass  ;  they  are  linked  with  its  impervi- 
ousness  to  water  and  its  plasticity  in  a  wet  state,  and  all  depend 
upon  the  fineness  of  grain  of  the  particles  making  up  the  clay. 
Each  property  is  most  pronounced  when  the  fineness  of  grain  is 
fully  developed  by  kneading  the  clay  in  a  wet  state.  The  particles 
of  a  piece  of  clay  that  has  been  subjected  for  a  time  to  the  action 
of  the  weather  gradually  rearrange  themselves  under  the  alternate 
wettings  and  dryings,  freezings  and  thawings,  and  unite  into 
loose  groups,  so  that  the  whole  mass  simulates  a  coarser  grained 
material  which  shrinks  less  on  drying  and  is  then  more  easily 
powdered. 

Since  compounds  of  lime  act  upon  the  clay  in  a  similar  way 
by  causing  the  finest  particles  to  clot  together,  it  is  necessary 
to  examine  our  soils  a  little  both  as  to  the  amount  of  lime 
they  contain  and  their  behaviour  towards  that  substance.  The 
most  universal  compound  of  lime  is  the  carbonate,  which  exists 
in  a  comparatively  pure  state  as  chalk  or  limestone  and  when 


202  THE  BOOK  OF  NATURE  STUDY 

strongly  heated  parts  with  its  carbonic  acid  to  pass  into  the 
state  of  quicklime.  Quicklime  in  its  turn  has  a  great  attraction 
for  water  and  carbonic  acid ;  it  greedily  takes  up  water  to 
become  slaked  lime,  and  slaked  lime  will  quickly  absorb  car- 
bonic acid  to  go  back  to  carbonate  of  lime.  Pour  a  little  dilute 
hydrochloric  acid  upon  a  piece  of  chalk  in  a  dish,  there  is  a 
violent  effervescence  due  to  the  carbonic  acid  expelled  by  the 
stronger  hydrochloric  acid  ;  repeat  the  same  experiment  with  the 
different  samples  of  soil,  some  of  them  will  be  sure  to  effervesce  a 
little,  but  with  others  the  bubbles  of  carbonic  acid  will  be  barely 
perceptible  because  when  there  is  less  than  about  i  per  cent, 
of  carbonate  of  lime  in  the  soil  the  carbonic  acid  dissolves  in  the 
liquid  as  fast  as  it  is  set  free.  Take  a  little  of  the  fine  clay  or 
even  of  the  clay  soil,  rub  it  up  into  a  paste  with  water,  and  then 
make  up  two  large  jars  of  turbid  clayey  water,  using  distilled 
or  rain  water ;  add  to  one  of  them  a  little  lime  or  a  few 
cubic  centimetres  of  clear  lime-water  and  put  the  jars  aside 
to  stand.  As  before,  they  will  take  some  time  to  clear,  but  the 
lime  in  the  one  jar  will  bring  about  a  much  more  complete  and 
earlier  clearing,  as  though  it  had  transformed  the  clay  into 
coarser  particles  more  of  the  nature  of  fine  sand.  It  is  now 
easy  to  understand  why  the  brick  worked  up  with  lime  gave 
various  indications  of  having  been  rendered  more  coarsely 
grained,  such  as  its  reduced  shrinkage  on  drying ;  the  lime  com- 
pounds have  the  power  of  making  the  finest  clay  particles  bunch 
up  together  or  "  flocculate,"  until  they  behave  like  a  smaller 
number  of  larger  ones.  All  the  soluble  salts  of  lime  act  thus, 
sulphate  of  lime  or  gypsum,  for  example,  and  carbonate  of  lime, 
because  it  becomes  so  readily  bi-carbonated  and  dissolved  by  the 
carbonic  acid  in  the  soil  water. 

Flocculation  of  the  clay  particles  is  not,  however,  the  only 
action  brought  about  by  the  carbonate  of  lime  we  have  recognised 
in  the  soil ;  it  also  behaves  as  an  anti-acid  or  neutraliser  of  the 
injurious  acids  which  are  often  produced  by  the  decay  of  organic 
matter  in  the  soil.  Moisten  a  little  of  the  peaty  soil  and  leave 
it  for  some  time  in  contact  with  a  piece  of  blue  litmus  paper  ; 
as  a  rule  the  litmus  will  be  reddened  by  the  acids  contained  in 
the  decaying  vegetable  matter  of  the  peat.  Now  grind  up  a 


THE  PROPERTIES  OF  SOILS  203 

little  chalk  and  mix  it  with  the  peat  before  applying  it  to  the 
litmus  paper  ;  the  red  colour  of  the  litmus  will  be  changed  again 
back  to  blue.  Soils  derived  from  chalk  or  limestone  often 
contain  large  proportions  of  carbonate  of  lime,  and  the  presence 
of  a  little  is  necessary  to  the  building  up  of  a  fertile  or  even  of  a 
healthy  soil,  though  sands  and  clays  are  to  be  found  in  which  it 
can  hardly  be  detected. 

One  other  constituent  which  plays  an  important  part  in 
the  soil,  the  organic  matter  or  humus,  the  debris  of  vegetable 
origin,  has  already  been  noticed  as  giving  the  soil  proper  rather 
a  darker  colour  than  the  subsoil.  Weigh  out  into  porcelain 
basins  about  ten  grams  each  of  the  clay  soil  and  subsoil,  the 
alluvial  soil  and  subsoil,  and  the  peat  soil,  each  of  which  had 
been  put  into  the  oven  for  a  few  hours  previously  to  get 
thoroughly  dry,  then  char  them  for  some  hours  over  a  Bunsen 
burner,  or  best  of  all  in  a  muffle  furnace.  At  first  the  colour 
of  the  soil  will  darken,  but  gradually  it  will  change  to  a 
bright  red  as  the  whole  of  the  carbonaceous  matter  burns  away. 
After  cooling,  re-weigh  the  dishes ;  the  loss  of  weight  represents 
the  organic  matter,  though  it  includes  also  a  certain  amount  of 
water  that  was  previously  in  chemical  combination  with  the  clay 
and  kindred  constituents  of  the  soil.  However,  by  far  the  larger 
part  of  the  loss  is  due  to  the  organic  matter,  and  from  the  ex- 
periment it  will  be  safe  to  conclude  that  the  peaty  soil  contains 
an  exceptional  amount  of  humus,  and  that  clay  soils  generally 
contain  more  than  sandy  ones.  Soils  also  are  always  much  richer  in 
humus  than  the  subsoils,  except  in  the  case  of  alluvial  soils,  which 
do  not  differ  much  in  composition  from  their  subsoils,  because 
both  have  been  alike  washed  from  other  land,  carried  down  by  the 
stream,  and  redeposited.  The  smell  given  off  in  the  early  stages 
of  charring  by  any  of  these  soils  suggests  the  presence  of  nitro- 
genous compounds,  but  this  can  be  better  demonstrated  by 
mixing  with  some  of  the  soil  in  a  separate  dish  before  heating  a 
little  soda-lime  or  even  lime  itself;  the  smell  of  ammonia  will 
soon  be  palpable,  and  its  presence  may  be  confirmed  by  holding  a 
reddened  litmus  paper  in  the  escaping  gases.  Without  pushing 
the  matter  further,  all  soils  can  be  shown  to  possess  a  store  of 
organic  matter  containing  nitrogen — the  humus  as  it  is  some- 


204  THE  BOOK  OF  NATURE  STUDY 

times  called — which  constitutes  the  chief  reserve  of  fertility  in  the 
soil. 

It  has  been  demonstrated,  however,  in  previous  chapters  that 
the  plant's  roots  can  only  take  in  nutriment  which  is  dissolved  in 
the  water  present  in  the  soil,  yet  none  of  the  substances  hitherto 
described  as  making  up  the  soil — the  sand,  the  clay,  the  chalk, 
the  humus — are  capable  of  dissolving  in  water.  As  a  matter  of 
fact,  the  actual  substances  which  go  to  feed  the  plant  exist  in 
comparatively  small  quantities  in  the  soil,  and  at  any  time  only 
traces  of  them  are  present  in  the  soil  water,  though  they  may  be 
constantly  renewed  as  they  are  removed  by  the  plant.  Take  the 
small  quantities  of  water  which  have  percolated  through  soil 
in  a  previous  experiment,  filter  if  need  be,  and  evaporate  them 
carefully  to  dryness  in  a  clean  porcelain  basin — a  very  small 
quantity  of  saline  residue  will  be  left  in  the  basin,  but  it  repre- 
sents the  nutrient  materials  which  were  immediately  available  for 
plants  living  in  those  soils.  It  would  be  going  beyond  our  present 
object  to  examine  this  residue  in  any  detail,  but  one  of  the  con- 
stituents is  of  so  much  importance  that  it  cannot  be  entirely 
passed  over.  It  is  well  known  that  nitre  in  some  form  or  other- 
either  the  saltpetre  that  is  extracted  from  Indian  soils,  the  nitrate 
of  soda  which  comes  from  Chile,  or  the  nitrate  of  lime  which  can 
sometimes  be  scraped  off  old  walls  of  buildings — is  in  certain 
places  a  product  of  the  soil,  and  can  be  extracted  from  it  on  a 
commercial  scale.  To  a  small  extent  one  of  these  nitrates 
is  present  in  all  fertile  soils.  The  most  sensitive  test  to  apply 
is  a  solution  of  di-phenylamine  in  sulphuric  acid,  and  if  a  little 
of  this  be  poured  on  to  the  dry  soil  residue  in  the  porcelain  basin 
it  will  assume  an  intense  blue  colour,  just  the  same  colour  as 
will  be  obtained  by  pouring  the  solution  on  a  tiny  crystal  of 
nitre  in  another  basin  (di-phenylamine  must  only  be  used  as  a 
test  with  dry  or  nearly  dry  substances).  This  nitrate  represents 
the  final  soluble  state  of  the  nitrogenous  humus  previously  re- 
cognised in  the  soil;  it  is  in  this  form  the  plants  supply 
themselves  with  the  nitrogen  they  want.  At  first  sight  it  is  not 
exactly  easy  to  understand  how  the  dark  carbonaceous  matter 
of  the  soil,  though  it  does  contain  nitrogen,  can  ever  pass  into 
substances  like  nitre,  and  indeed  in  the  laboratory  the  task  of 


WATER  RETAINED  BY  EQUAL  WEIGHTS  OF  VARIOUS  SOILS 

I  =  a  coarse  sand,  2  =  peaty  soil,  3  =  alluvial  loam,  4  =  clay,  5  =  clay  after 
puddling,  in  which  case  the  bulk  of  the  water  has  not  percolated  (/.  198). 


PHOTOGRAPHS  OF  CULTURES  OF  SOIL  ORGANISMS 

1  =  Moulds  growing  in  medium  containing  ammonium  salts  but  no  cal- 

cium carbonate  (p.  206). 

2  =  Flask  in  which  algae  have  appeared;   notice  the  bubbles  of  oxygen. 

3  =  Medium  without  nitrogen  in  which  azolobacter  has  developed. 


EXPERIMENT  TO 
ILLUSTRATE 
THE  RISE  OF 
WATER  IN  SOILS 
BY  CAPILLAR- 
ITY OR  SUR- 
FACE TENSION 

1  =clay, 

2  =  loam, 

3  =  fine  sand, 

4  =  coarse  sand. 

Photograph  taken  twenty- 
four  hours  after  starting 
the  experiment  (/.  199). 


THE  PROPERTIES  OF  SOILS  205 

converting  the  one  compound  of  nitrogen  into  the  other  by 
purely  chemical  means  would  be  a  matter  of  some  difficulty. 
This  brings  to  the  front  another  aspect  of  the  soil,  one  difficult 
to  verify  by  simple  personal  observations,  but  one  that  requires 
to  be  appreciated  before  a  proper  understanding  of  some  of  the 
simplest  problems  of  soil  management  can  be  reached.  The 
soil  is  not  merely  a  frame-work  of  sand  and  clay,  in  which  the 
plants  anchor  themselves  by  their  roots,  and  from  which  they 
draw  water  and  a  certain  amount  of  nutriment  circulating  in  that 
water ;  it  is  also  a  swarming  laboratory  of  minute  living  agents 
—moulds,  bacteria,  and  kindred  organisms — some  of  which  are 
always  preparing  the  food  for  the  higher  plants,  while  others 
are  wasting  it  or  are  injurious  in  other  ways.  A  few  simple 
experiments  can  be  made  to  illustrate  the  living  nature  of 
the  soil ;  all  that  is  necessary  is  the  preparation  of  a  litre  of 
a  nutrient  solution  containing  0*1  gram  of  magnesium  sulphate, 
0*2  gram  of  potassium  phosphate,  and  0*1  gram  of  sodium 
chloride. 

Thoroughly  clean  six  small  flasks,  and  add  100  centimetres 
of  the  nutrient  solution  to  each  ;  to  three  of  them  also  add  one 
gram  of  sugar;  to  the  other  three  add  0*1  gram  of  ammonium 
sulphate ;  then  to  one  flask  in  each  set  add  about  half  a  gram  of 
calcium  carbonate.  Plug  the  mouths  of  the  flasks  fairly  tightly 
with  cotton  wool,  put  them  all  in  a  vegetable  steamer,  and  heat 
them  up  to  the  temperature  of  boiling  water  for  half  an  hour 
or  so.  The  heating  sterilises  the  contents,  and  as  the  cotton 
wool  plugs  exclude  all  further  entry  of  organisms  no  change  will 
take  place  inside  the  flask,  though  the  air  has  free  access  through 
the  cotton  wool.  When  the  flasks  are  quite  cold  get  ready  a 
small  quantity  of  fresh  soil,  say  from  a  garden,  and,  lifting  out 
the  plug  of  cotton  wool  for  a  moment,  drop  in  with  a  spatula  a 
piece  of  soil  about  as  big  as  a  hazel  nut  and  replace  the  plug. 
Now  take  two  of  the  flasks  without  calcium  carbonate,  one 
with  and  the  other  without  sugar,  and  heat  it  up  to  boiling- 
point  for  two  or  three  minutes,  repeating  this  operation 
on  the  following  day.  The  double  boiling  will  effectually 
sterilise  the  contents  of  the  two  flasks,  which  will  now  serve 
as  checks  containing  dead  instead  of  the  living  soil  in 


206 


THE  BOOK  OF  NATURE  STUDY 


the  others.     The  scheme  of  the  experiment  is  best  summarised 
in  a  table. 


Contents  alike  as  regards 

Treatment 

No. 

Nutrient  Solution 

after  Soil 

Result. 

and  Soil. 

added. 

i 

+  Ammonium 

Boiled. 

Nil. 

sulphate. 

2 

.  . 

.  . 

Some  moulds,  some- 

times nitrates. 

3 

.  . 

+  Calcium  car- 

. . 

Nitrates  formed. 

bonate. 

4 

+  Sugar. 

, 

Boiled. 

Nil. 

5 

+  Sugar. 

.  . 

.  . 

Some  moulds. 

6 

+  Sugar. 

+  Calcium  car- 

. . 

Gas  and  brown  scum, 

bonate. 

eventually  nitrates. 

Place  the  flasks  aside  in  a  warm  dark  cupboard  and  examine 
those  containing  sugar  after  a  week  or  ten  days  has  elapsed.  The 
liquid  in  the  flask  without  carbonate  of  lime  will  be  all  covered 
with  moulds,  mostly  white  in  colour,  but  others  that  are  green 
and  black  and  even  pink  may  also  be  in  evidence.  The  contents 
of  the  flask  containing  carbonate  of  lime  will  show  a  very  different 
growth,  probably  a  dirty  skin  much  blown  with  bubbles  of  gas. 
Replace  this  flask  in  the  cupboard  for  examination  in  two  or  three 
months'  time.  The  soil  introduced  has  evidently  started  very 
considerable  actions,  which  are  further  of  an  entirely  different 
type  according  as  carbonate  of  lime  had  been  added  or  not. 
The  soil,  in  fact,  contains  a  great  variety  of  organisms,  some  of 
which  flourish  best  in  a  slightly  acid  medium,  while  others  can 
only  develop  where  it  is  kept  neutral.  That  it  is  the  living 
soil  which  starts  these  changes  is  seen  from  the  absence  of  action 
in  the  check  flask  which  had  been  heated  after  the  addition  of 
the  soil. 

The  other  three  flasks  should  be  left  for  a  month,  and  then  a 
little  of  the  clear  liquid  in  each  must  be  evaporated  in  a  basin 
and  tested  with  di-phenylamine  for  nitrates.  Here  again  there 
will  be  no  evidence  of  action  in  the  flask  which  has  been  heated 
after  the  addition  of  the  soil,  and  of  the  other  two,  inoculated 
with  living  soil,  only  the  one  containing  carbonate  of  lime  will 


THE  PROPERTIES  OF  SOILS  207 

show  any  marked  reaction  for  nitrates ;  in  the  other  a  few  moulds 
will  be  growing,  and  nitrates  may  be  found  if  the  added  soil  had 
contained  much  calcium  carbonate.  The  soil  contains  bacteria 
which  slowly  change  other  compounds  of  nitrogen  like  ammonia 
into  nitrates,  but  which  can  only  work  in  a  solution  kept  neutral 
by  the  presence  of  a  base  like  carbonate  of  lime. 

If  the  liquid  in  flask  6  be  also  examined  when  two  or  three 
months  have  elapsed  it  will  show  a  reaction  for  nitrates,  although 
no  nitrogen  compound  had  originally  been  added  to  the  flask. 
The  nitrogen  it  contains  has  been  gathered  from  the  atmosphere 
by  the  bacteria  forming  the  brown  skin  first  appearing,  the  trans- 
formation of  which  into  nitrate  is  the  later  work  of  another  group 
of  bacteria. 

A  good  example  of  the  cycle  of  changes  through  which  nitro- 
genous materials  in  the  soil  are  always  passing  may  be  obtained 
by  making  up  another  flask  of  nutrient  solution  as  previously 
described,  and  adding  to  it  both  the  half  gram  of  calcium  carbonate 
and  0-2  of  a  gram  of  peptone  (one  of  the  most  complex  nitrogenous 
compounds),  inoculating  with  soil  as  before.  At  the  end  of  a 
week  or  so  evidence  of  the  first  change  to  take  place — putrefaction 
—will  be  obtained  from  the  smell  of  the  flask,  while  the  liquid 
will  be  seen  to  be  turbid  with  the  numbers  of  putrefactive  organ- 
isms that  have  developed.  After  another  week  or  fortnight 
the  putrefactive  smell  will  be  exchanged  for  a  faint  smell  of 
ammonia,  the  formation  of  which  represents  a  still  further  step 
in  the  break  down  of  the  peptone.  Again,  leave  the  flask  in 
the  dark  for  a  month  and  its  contents  will  begin  to  show  the 
reaction  for  nitrates,  which  are  now  being  produced  from  the 
ammonia.  Now  bring  the  flask  into  the  light  for  some  weeks  ; 
in  time  a  green  growth  of  algae  will  appear,  accompanied  by 
the  evolution  of  oxygen  when  the  light  is  bright.  At  the  same 
time  both  nitrates  and  ammonia  will  have  disappeared  from 
the  liquid  ;  they  have  been  reconverted  into  protein  in  the  sub- 
stance of  the  algae.  Thus  after  the  bacteria  have  taken  the 
original  protein  and  reduced  it  step  by  step  to  nitrates  the  plant 
steps  in,  and  by  the  aid  of  the  energy  of  light  rebuilds  another 
complex  protein. 

It  is  impossible  at  this  stage  to  discuss  with  any  particularity 


208  THE  BOOK  OF  NATURE  STUDY 

the  various  groups  of  organisms  at  work  in  the  soil ;  some  of 
them  convert  such  materials  as  farmyard  manure,  roots,  leaves, 
and  the  like  into  humus  and  simple  compounds  like  the  nitrates 
upon  which  plants  can  feed.  Others  rob  the  higher  plants  of  the 
food  that  is  in  the  soil  and  use  it  for  their  own  nutriment,  although 
in  the  end  it  must  be  returned  into  circulation  for  the  use  of  the 
plant.  One  great  group  of  bacteria,  amongst  which  are  those 
forming  the  brown  skin  in  flask  6,  enrich  the  soil  by  gathering 
nitrogen  from  the  atmosphere,  whilst  others  waste  the  nitrogenous 
compounds  present  in  the  soil  by  converting  them  back  to  gas. 
Others  give  rise  to  substances  hurtful  to  the  growth  of  plants ; 
others,  fortunately  more  rare,  are  capable  of  setting  up  disease  in 
human  beings  if  they  find  entrance  through  a  wound.  The  relative 
predominance  of  one  or  other  group  depends  upon  many  con- 
ditions,—upon  the  warmth  of  the  soil,  its  degree  of  moisture  and 
aeration,  its  supply  of  this  or  that  nutrient  material,  etc. ;  in  fact, 
bacteria  are  influenced  by  much  the  same  set  of  factors  as  are  the 
higher  plants.  Without  bacteria  in  the  soil  the  growth  of  our 
crops  would  be  practically  impossible,  and  many  of  the  common 
operations  of  cultivation  and  management  are  unconsciously 
directed  towards  effecting  some  change  in  the  bacterial  actions 
in  the  soil  that  will  eventually  result  in  benefit  to  the  plant. 

THE  CHARACTERISTICS  OF  DIFFERENT  SOILS 

It  has  already  been  seen  how  different  kinds  of  rock  give 
r&e  to  sedentary  soils  of  various  types,  which  again  in  their  turn, 
after  sorting  by  the  river,  result  in  one  or  two  distinct  alluvial 
soils  ;  it  is  interesting  and  often  valuable,  from  the  farming  and 
gardening  point  of  view,  to  study  what  kind  of  vegetation  is 
associated  with  each  type  of  soil.  We  have  seen  how  the  water- 
retaining  powers  of  soil  vary  with  the  materials  from  which  it  is 
made ;  its  water-retaining  power  will  affect  its  temperature  and  a 
dozen  other  factors,  rendering  it  more  suitable  for  one  plant  than 
for  another.  Differences  of  chemical  composition  act  in  the  same 
way.  In  consequence,  wherever  plants  have  free  play,  as  on  un- 
cultivated land  or  a  meadow  or  amongst  weeds  of  arable  land, 
the  vegetation  varies  very  greatly  in  passing  from  one  type  of 


CHARACTERISTICS  OF  DIFFERENT  SOILS         209 

soil  to  another,  and  plants  may  be  used  as  guides  in  deciding 
upon  the  nature  and  fertility  of  a  given  piece  of  land. 

The  photograph  shows  typical  samples  of  turf  taken  from 
two  of  the  experimental  plots  at  Rothamsted,  which  have  been 
receiving  a  different  kind  of  manure  every  year  for  half  a 
century  before  the  photograph  was  taken.  The  great  contrast 
in  the  character  of  the  vegetation  in  the  two  plots  has  been 
brought  about  solely  by  a  difference  in  the  nature  of  the  nitrogen 
compounds  supplied  ;  one  compound  has  favoured  certain  species 
of  grass  which  have  become  dominant,  while  in  the  other  case 
a  different  set  of  species  have  been  brought  to  the  front  by  the 
particular  manure  that  has  been  given  so  repeatedly. 

It  is  not  so  much  that  the  variations  in  composition,  chemical 
or  physical,  between  different  soils  are  sufficient  to  prevent  the 
growth  of  a  given  plant  in  one  place  while  encouraging  it  in 
another  ;  on  the  contrary,  the  differences  are  so  small  and  the 
adaptability  of  most  plants  so  great  that,  as  we  see  in  gardens, 
the  same  plants  will  flourish  on  almost  all  varieties  of  soil.  In 
nature,  however,  the  wild  plant  has  not  the  scope  and  freedom 
possessed  by  the  garden  plant ;  food  is  scarcer  and  there  is  an 
enormous  competition  for  it,  under  which  conditions  a  given 
species  only  requires  to  receive  a  slight  advantage  over  its  neigh- 
bours to  become  dominant,  while  the  least  disadvantage  will 
rapidly  cause  it  to  be  pushed  off  the  field  altogether.  The 
plant  lives  in  a  state  of  fierce  competition,  neighbours  are 
encroaching  on  every  side,  some  by  their  roots  trying  to  rob 
it  of  food  and  water,  others  by  their  superior  height  depriv- 
ing it  of  light.  Every  year  the  crowding  is  intensified  by  the 
vast  number  of  new  seeds  that  are  shed  and  by  the  way  each 
plant  colony  tries  to  push  into  fresh  ground.  How  severe  this 
competition  becomes  may  be  seen  from  the  fact  that  our  domes- 
ticated plants,  either  of  farm  or  garden,  are  rarely  able  to  get  a 
footing  outside  cultivated  land,  and  indeed  only  continue  to 
exist  there  as  long  as  they  are  kept  free  from  the  competition  of 
weeds.  Even  wheat,  with  its  vigour  and  adaptability  to  all 
sorts  of  conditions  of  soil  and  climate,  is  soon  crowded  out  by  our 
native  weeds,  as  may  be  seen  from  the  following  account  of  an 
experiment  at  Rothamsted.  "  In  1882  about  an  acre  of  the 

VOL.  V. — 14 


210  THE  BOOK  OF  NATURE  STUDY 

upper  end  of  the  Broadbalk  field,  which  had  then  been  carrying 
wheat  for  forty  years  in  succession,  was  not  harvested ;  the  crop 
was  allowed  to  stand  and  shed  its  seed  without  cultivation  of 
any  kind.  In  the  following  season  a  fair  quantity  of  wheat  came 
up  on  this  part  of  the  field,  but  gradually  got  weaker  as  the  season 
advanced  and  the  weeds  increased  their  hold  on  the  land. 

"  The  wheat  was  still  left  to  struggle  on  without  cultivation, 
and  by  the  fourth  season  only  three  or  four  stunted  plants  could 
be  found,  each  carrying  but  one  or  two  grains  in  the  ear.  With 
these  the  wheat  disappeared,  and  has  never  been  seen  again  in 
that  part  of  the  field/ ' 

From  this  example  it  may  be  understood  how  strenuous  is 
the  competition  existing  in  any  meadow  or  hedge  bottom,  and 
how,  if  the  conditions  become  ever  so  slightly  less  favourable 
to  one  species  than  to  its  neighbours  it  has  very  little  chance  of 
surviving,  except  sparsely  and  locally  where  some  accident  restores 
the  balance  in  its  favour.  The  differences  which  render  one  kind 
of  soil  suitable  to  a  given  plant  or  cause  it  to  be  displaced  by  a 
kindred  species,  are  often  very  small  indeed,  so  that  it  becomes 
difficult  to  ascertain  their  exact  nature.  For  example,  in 
most  districts  of  England  that  are  not  too  near  the  depredations 
of  large  towns  few  flowers  are  so  plentiful  as  the  Primrose  ;  every 
copse,  every  bankside,  the  edges  of  every  ditch  are  full  of  them. 
Yet  here  and  there  areas  may  be  found  where  every  condition 
seems  to  be  suitable,  yet  the  Primrose  is  either  entirely  absent  or 
is  only  found  in  rare  patches  ;  in  the  woods  its  habitual  com- 
panions, the  Wood  Anemone  and  the  Bluebell,  may  be  common 
enough,  and  outside  in  the  open  fields  Cowslips  may  be  abundant, 
but  the  Primrose  itself  is  wanting. 

Many  reasons  may  be  advanced  for  this  erratic  distribution 
but  as  yet  the  author  has  not  found  any  one  that  is  valid, 
and  similar  cases  occur  everywhere.  Always,  however,  the 
element  of  competition  is  of  more  moment  than  any  direct  en- 
couraging or  injurious  effect  of  the  soil  itself  upon  the  plant. 
To  take  an  example,  one  of  the  most  striking  cases  of  local  dis- 
tribution of  a  British  plant  is  the  way  the  Yellow  Horned  Poppy 
is  confined  to  the  otherwise  almost  bare  shingle  banks  round  our 
coasts ;  one  would  suppose  it  must  love  the  salt  spray  and  the 


CHARACTERISTICS  OF  DIFFERENT  SOILS         211 

wind,  and  the  fierce  alternations  of  heat  and  cold  on  those  barren 
wastes.  Yet  if  some  of  its  seed  be  sown  in  an  ordinary  garden 
soil  it  will  grow  with  a  vigour  and  lavishness  which  show  that 
it  prefers  a  fat  soil  and  an  easy  life  as  much  as  other  plants  do. 
The  Horned  Poppy  is  not  established  on  the  shingle  because  it 
likes  either  the  food  or  the  climate,  but  because  it  can  there 
escape  from  a  killing  competition ;  inland  it  is  soon  crowded 
out  by  stronger  forms  of  vegetation,  out  on  the  shingle  its  long 
tap  root  enables  it  to  keep  alive  when  all  other  plants,  even  the 
grasses,  are  unable  to  obtain  any  nutriment. 

It  does  not  love  the  shower  nor  seek  the  cold, 
This  neither  is  its  courage  nor  its  choice 
But  its  necessity  in  being  old. 

The  study  of  the  local  distribution  of  plants  and  their  associa- 
tion with  particular  types  of  soil  is  one  of  great  interest,  which 
may  be  taken  up  single  handed  in  almost  any  part  of  Great  Britain  ; 
it  is  also  one  in  which  real  and  needed  contributions  to  knowledge 
may  be  made  by  the  solitary  worker.  The  requisites  will  include 
a  sheet  of  the  geological  survey  of  the  district,  which  can  be 
obtained  through  any  post  office,  though  care  should  be  taken 
to  order  what  is  termed  the  "  drift  "  map,  which  shows  the 
superficial  deposits  giving  rise  to  "  soils  of  transport,"  as  well  as 
the  underlying  solid  deposits  which  give  rise  to  "  sedentary 
soils  "  wherever  they  come  to  the  surface.  This  map  will  show 
how  many  different  types  of  soil  may  be  expected  to  occur  in  the 
area  under  examination,  and  typical  examples  should  be  studied 
by  washing  into  sand  and  clay,  and  by  testing  with  acid  for 
carbonate  of  lime,  until  their  essential  characters  are  known.  Two 
formations,  geologically  quite  distinct;  as  shown  on  the  map,  may 
give  rise  to  soils  that  are  identical  for  all  working  purposes ; 
on  the  other  hand,  the  sedentary  soils  derived  from  one  and  the 
same  formation  may  alternate  between  sand  and  clay,  or  be 
calcareous  in  one  band  and  short  of  lime  in  another.  But  in 
a  general  way  the  soils  will  follow  the  geological  map,  although 
in  order  to  make  sure  of  the  boundaries  and  to  supplement  the 
information  conveyed  by  the  map,  it  is  often  necessary  to  carry 
a  long  auger  wherewith  to  bore  out  a  little  soil  from  a  depth 


212  THE  BOOK  OF  NATURE  STUDY 

of  eighteen  inches  or  so.  By  examining  this  with  acid  or  by 
rubbing  it  up  with  water,  to  see  whether  it  is  clayey  or  sandy, 
it  can  generally  be  allotted  to  one  or  other  of  the  formations  in 
question.  The  acidity  or  otherwise  of  the  soil  to  litmus  paper 
should  also  be  tested  in  the  field,  and  notes  should  be  kept  on 
a  point  that  is  not  indicated  either  by  the  map  or  the  examina- 
tion of  the  soils  in  the  laboratory,  i.e.  the  wetness  or  dryness  of 
the  land,  and  whether  the  wetness  is  due  to  a  local  spring  or  to 
a  high  level  of  the  ground  water.  A  few  preliminary  walks  will 
give  a  general  idea  of  the  distribution  of  the  vegetation  and  will 
indicate  certain  species  as  suitable  for  detailed  study.  A  small 
selection  should  be  made  from  these  —  one  for  the  hedgerows, 
another  for  the  woods,  a  characteristic  grass  and  a  cornfield 
weed— and  future  walks  should  be  wholly  directed  to  recording 
the  frequency  or  absence  of  these  particular  species  from  in- 
dividual pieces  of  land.  The  records  should  be  laid  down  on  a 
rough  tracing  from  the  geological  map,  which,  when  the  area  has 
been  thoroughly  traversed,  will  at  once  show  if  any  correlation 
exists  between  the  nature  of  the  soil  and  the  occurrence  of  the 
particular  species. 

In  considering  the  vegetation  of  different  soils  the  factors 
that  have  chiefly  to  be  taken  into  account  are,  on  the 
physical  side,  the  supply  of  water,  and  on  the  chemical,  the  acidity 
or  alkalinity  of  the  soil.  Plants  are  often  described  as  lime  loving 
or  lime  hating,  and  though  in  some  cases  the  carbonate  of  lime 
in  the  soil  may  have  a  direct  effect  for  good  or  evil  upon  the  plant, 
the  really  dominant  factor  is  whether  the  soil  contains  enough 
carbonate  of  lime  to  keep  it  in  a  neutral  or  even  a  positively  alkaline 
condition.  As  regards  water  supply,  plants  which  frequent  soils 
habitually  short  of  water  have  devised  various  methods  for  reduc- 
ing transpiration  ;  the  leaf  is  often  constructed  so  as  to  expose  a 
minimum  of  surface,  or  is  covered  with  hairs  or  coated  with  wax, 
hence  the  hoary  glaucous  appearance  the  vegetation  of  a  really 
dry  region  usually  presents.  Storage  organs  like  bulbs  have  been 
devised  to  carry  other  plants  through  regularly  recurring  periods 
of  drought.  Although  these  structures,  designed  to  save  trans- 
piration, are  commonly  found  on  plants  growing  in  dry  areas, 
they  also  occur  where  one  would  least  expect  them,  on  plants. 


CHARACTERISTICS  OF  DIFFERENT  SOILS         213 

living  on  water-logged  peaty  land  or  on  salt  marshes.  By 
reducing  transpiration  they  reduce  the  intake  of  water,  which  is 
necessary  when  the  soil  water  contains  injurious  substances,  as 
it  does  in  the  peat  bogs  and  the  salt  marshes. 

Keeping  these  general  principles  in  mind,  we  may  now  review 
briefly  the  characteristics  of  some  of  the  main  soil  types  and 
the  vegetation  associated  with  them. 

CLAY  SOILS. — There  exist  wide  differences  in  structure  between 
the  various  soils  that  are  commonly  called  clays.  A  soil  which 
is  in  the  main  composed  of  very  fine  sand  without  any  admix- 
ture of  coarser  particles,  bound  together  by  only  10  to  15  per 
cent,  of  what  may  be  termed  true  clay,  will  be  so  sticky  and 
wet  that  it  will  be  regarded  as  a  clay ;  yet  under  cultivation  it 
will  behave  in  many  respects  differently  from  the  heavy  soils 
which  on  examination  show  30  to  50  per  cent,  of  true  clay. 
The  most  pronounced  clay  soils  occur  in  the  Midlands  and  south 
and  east  of  England  ;  in  these  districts  the  Kimmeridge,  Oxford, 
London  and  Weald  clay  formations  give  rise  to  extremely  heavy 
soils  ;  whereas  in  regions  of  higher  rainfall  the  soils  become  so 
much  more  washed  free  of  their  finest  particles  that  their  texture 
is  distinctly  lighter.  As  clay  soils  are  distinguished  both  by  their 
power  of  retaining  water  and  their  imperviousness  to  percolation, 
it  follows  that  they  are  generally  wet  throughout  the  winter 
months,  when  the  rainfall  is  greater  than  the  evaporation.  As 
the  spring  advances  such  soils  are  slow  to  warm  up  because  of 
the  water  with  which  they  are  laden ;  for  not  only  does  water 
require  more  heat  than  soil  to  raise  its  temperature  by  a  given 
amount,  but  also  it  is  always  withdrawing  heat  from  the  land  as 
it  evaporates.  To  evaporate  a  pound  of  water  requires  more  than 
thirty  times  the  heat  necessary  to  warm  it  up  from  freezing-point  to 
summer  temperature,  and  even  this  latter  amount  is  five  times  as 
great  as  would  be  wanted  to  heat  a  pound  of  soil  to  the  same 
extent.  In  consequence,  clay  soils  are  cold  and  tend  also  to  cool 
the  air  in  contact  with  them,  and  the  less  the  water  is  able  to 
get  away  from  them  the  cooler  they  remain  ;  drainage  therefore 
warms  a  clay  soil  by  freeing  it  of  water  more  rapidly  and  keeping 
down  the  level  of  permanent  wrater,  thus  reducing  the  capillary 


214  THE  BOOK  OF  NATURE  STUDY 

rise  to  the  surface,  and  the  consequent  evaporation  and  cooling. 
Their  coldness  causes  clay  soils  to  be  late  and  slow  growing  in  the 
spring  ;  they  are  therefore  unsuited  to  market  gardening  where  a 
quick  succession  of  crops  is  aimed  at.  As  a  set-off  they  hold 
their  growth  well  into  the  summer,  and  do  not  suffer  from  short 
droughts ;  a  long-continued  drought,  however,  punishes  the  plants 
on  a  clay  soil  very  severely,  because  when  once  the  original  stock 
of  water  is  exhausted  its  renewal  by  capillarity  is  very  slow.  The 
shrinkage  of  the  clay  on  drying  also  results  in  deep  and  wide  cracks, 
which  further  aggravate  the  loss  of  water.  If  a  field  section  of  a 
heavy  clay  soil  be  examined  it  will  be  seen  that  the  plants  are 
comparatively  shallow  rooted,  partly  owing  to  the  difficulty  of 
penetration,  and  partly  to  the  abundance  of  water  that  is  usually 
present.  This  shallowness  of  the  root  system  contributes  to  the 
injurious  effect  of  a  long  drought  on  a  clay  soil.  Just  as  a  clay 
soil  is  late  to  start,  in  the  autumn  its  cooling  is  correspondingly 
slow,  and  in  consequence  plants  continue  to  grow  longer  on  clay 
than  on  sandy  soils  ;  in  some  cases  this  is  an  advantage,  in  others 
maturity  is  apt  to  be  deferred  until  bad  weather  sets  in.  Owing 
to  the  expense  and  uncertainty  of  spring  cultivation  on  clay 
soils  they  have  very  largely  been  laid  down  to  grass  since  the 
fall  in  agricultural  prices,  but  very  often  they  will  not  grow 
good  grass,  because  of  the  deficient  aeration  brought  about  by 
the  setting  together  of  the  soil  that  occurs  a  few  years  after 
the  arable  cultivation  has  ceased.  It  is  not  until  a  stock  of 
humus  has  been  built  up  and  the  soil  has  become  thereby 
once  more  open  and  friable  that  grass  really  does  well  on 
these  heavy  soils.  The  typical  crops  of  strong  land  are  Wheat, 
Beans,  and  Mangolds  ;  of  these  large  crops  can  be  grown,  and 
of  good  quality.  Certain  weeds  are  troublesome  — "  Black 
Bent  Grass "  and  "Field  Mint  "  in  the  arable  land,  but  as  a 
rule  weeds  are  not  abundant  on  cultivated  clay  land.  In  the 
pastures  "  Dyers  Weed/'  Buttercups,  and  the  thorny  form  of  the 
"  Rest-Harrow  "  are  common  weeds  ;  with  many  plants  spines  and 
thorns  become  strongly  developed  on  clay  land.  Owing  to  the 
lack  of  aeration  in  the  soil  the  grasses  are  apt  to  develop  a  stoloni- 
ferous  surface-rooting  habit,  and  "Bent  Grass "  —the  stoloni- 
ferous  creeping-rooted  form  of  "  Agrostis  alba  " — often  usurps 


CHARACTERISTICS  OF  DIFFERENT  SOILS         215 

nearly  the  whole  of  the  pasture.  The  characteristic  tree  of  clay 
land  is  the  Oak,  and  to  a  less  degree  the  Hornbeam;  conifers 
often  grow  well,  especially  those  which  like  a  soil  inclined  to 
acidity,  for  clay  soils  as  a  rule  contain  little  carbonate  of  lime. 
On  the  banks  and  waste  places  the  Wild  Carrot  and  the  Teazle 
are  among  the  plants  that  are  rather  characteristic  of  clay  land, 
as  also  is  the  Primrose. 

SANDY  SOILS. — Sandy  soils  may  be  found  of  all  degrees  of 
intensity,  varying  from  fine  sandy  loams,  excellent  for  cultivation, 
to  soils  almost  devoid  of  fine  particles  and  worthless  for  farming. 
Common  land  is  occasionally  situated  on  clay  but  the  majority 
of  tracts  of  unenclosed  common  or  heath  or  forest  consist  of  sands 
so  light  that  they  have  never  been  considered  worthy  of  bringing 
into  cultivation,  but  have  been  left  clothed  with  their  natural 
vegetation  of  Gorse  and  Heather.  Such  soils  are  generally  found 
to  be  also  devoid  of  carbonate  of  lime  ;  in  consequence  they 
accumulate  more  humus  than  would  be  expected  from  their 
openness  and  warmth,  especially  where  the  drainage  is  imperfect. 
On  examining  a  section  of  a  really  sandy  soil  it  will  be  observed 
that  the  roots  of  the  vegetation  are  abundant  and  penetrate  com- 
paratively deeply  ;  as  a  rule  also  it  will  be  seen  that  the  sand 
for  nine  or  ten  inches  down  has  been  bleached  by  the  removal 
of  the  brown  oxide  of  iron  which  is  the  chief  colouring  matter 
of  all  soils.  Below  the  bleached  portion  comes  a  thin  band  or 
pan  of  dark  coloured  oxide  of  iron,  dissolved  and  redeposited  from 
the  sand  above  ;  this  bleaching  and  iron  pan  occur  only  in  soils 
short  of  carbonate  of  lime.  Being  so  coarse  grained  and  free  from 
water,  sandy  soils  warm  up  rapidly  and  are  early  ;  if  plenty  of 
manure  can  be  given  they  induce  very  rapid  growth,  and  so  are 
well  suited  to  market  gardeners  and  small  holders.  They  do  not 
maintain  their  vegetation  well  through  the  summer,  but  growth 
is  again  rapid  with  the  cooler  and  moister  days  of  the  early  autumn. 

Among  the  cereal  crops,  barley  answers  best  on  sandy  land ; 
grass  is  generally  poor,  the  "  Soft  Brome  "  being  a  very  character- 
istic species,  while  the  "  Wavy-Hair  Grass  "  is  a  common  weed  of 
arable  sandy  land.  Among  trees  the  Spanish  Chestnut,  the  Silver 
Birch,  Holly,  and  several  of  the  conifers  are  generally  associated 


2i6  THE  BOOK  OF  NATURE  STUDY 

with  the  lighter  soils,  as  are  Gorse  and  Broom  among  shrubs. 
Foxgloves,  Bracken,  and  Heather  are  typical  plants.  Ornithopus 
and  one  or  two  vetches  are  common,  though  the  majority  of 
leguminous  plants  do  not  grow  freely  when  carbonate  of  lime 
is  lacking.  Among  weeds,  Spurrey,  the  small  Sorrel  Dock,  Corn 
Marigold,  and  Knawel  are  characteristic  ;  the  two  former  being 
particularly  indicative  of  lack  of  carbonate  of  lime  in  the  soil. 

CALCAREOUS  SOILS. — Not  all  soils  derived  from  chalk  or  lime- 
stone are  calcareous,  even  though  the  rock  may  be  found  unaltered 
a  very  short  distance  below.  Carbonate  of  lime  is  so  readily 
dissolved  by  natural  waters  charged  with  carbonic  acid  from  the 
soil  that  in  many  cases  it  has  been  washed  out  of  the  thin  layer 
of  surface  soil  existing  on  some  of  the  calcareous  formations. 
Hence  it  is  necessary,  when  studying  the  vegetation  of  an  area 
resting  on  chalk  or  limestone,  to  make  certain  of  the  presence 
or  absence  of  carbonate  of  lime  in  an  ostensibly  calcareous  soil 
before  drawing  any  conclusions  from  the  occurrence  of  a  given 
plant. 

Calcareous  soils  are  generally  dry,  warm  and  early  ;  most 
leguminous  plants  flourish  well  on  them,  notably  Lucerne  and 
Sainfoin  in  the  warmer  parts  of  the  country.  They  are  healthy 
for  stock,  though  snails,  slugs,  and  certain  insect  pests  are  trouble- 
some to  crops,  and  in  the  pastures  worms  are  always  specially 
abundant. 

The  most  characteristic  features  of  the  vegetation  on  calcareous 
soils  are  its  extreme  variety  and  floriferousness ;  on  no  other  soil 
can  so  many  brilliantly  coloured  and  strongly  scented  flowers 
be  found  at  all  periods  of  the  year.  The  Beech,  Yew,  and  Wild 
Cherry  are  typical  trees  ;  the  hedgerows  are  full  of  characteristic 
shrubs  like  Dogwood,  the  Mealy  Guelder  Rose  or  Wayfaring  tree, 
Clematis,  the  Beam  tree,  and  Sweetbriar.  Juniper  occurs  on  the 
open  downs,  as  also  does  Box  in  the  few  cases  where  it  is  truly 
wild.  The  Horseshoe  Vetch,  Burnet,  the  Dropwort,  some  of  the 
gentians,  various  orchids,  and  Sheep's  Scabious  and  many  labiates 
are  almost  confined  to  calcareous  pastures ;  while  Chicory  and 
Wild  Parsnip  are  common  in  waste  places.  Several  grasses  are 
confined  to  calcareous  soils,  as  are  several  ferns  to  calcareous 


CHARACTERISTICS  OF  DIFFERENT  SOILS         217 

rocks  ;  in  fact,  the  whole  vegetation  is  one  of  the  most  interesting 
to  study.  A  few  plants  also  refuse  to  grow  on  calcareous  soils; 
among  these  the  most  widely  known  are  Rhododendrons  and  some 
of  the  Heaths. 

ALLUVIAL  SOILS. — On  the  alluvial  soils  the  richest  land  of 
the  country  is  to  be  found,  though  often,  as  it  is  subject  to  floods 
or  has  permanent  water  but  a  short  distance  below  the  surface,  it 
is  not  suitable  to  arable  cultivation  but  remains  in  permanent 
pasture.  The  fertility  of  these  soils  is  due  to  the  fact  that  neither 
coarse  sand  nor  clay  predominate  in  them ;  they  consist  of  a 
very  even  mixture  of  particles  of  other  soils  that  have  been  graded 
by  running  water.  Moreover,  the  subsoil,  as  deep  as  the  deposit 
extends,  is  enriched  with  humus,  because  it  has  once  been  soil. 
There  is  generally  a  sufficiency  of  carbonate  of  lime  ;  indeed, 
without  it  really  rich  soil  is  hardly  possible. 

The  rich  pastures,  and  it  is  only  on  alluvium  as  a  rule  that 
true  "  fattening  "  land  is  to  be  found,  are  largely  covered  with 
Rye-grass,  to  which  they  owe  their  shining  effect  in  the  sunshine  ; 
on  drier  poorer  areas  Crested  Dogstail  and  Squirreltail  Grass  are 
common.  The  spots  where  the  drainage  is  deficient  are  generally 
marked  by  coarse  tufts  of  Aira,  or  by  the  presence  of  Rushes  and 
the  small  sedges  known  to  the  farmer  as  Carnation  Grass. 

The  characteristics  of  the  alluvial  soils  are  also  shared  by 
certain  loams  that  are  of  sedentary  origin  ;  these  are  the  typical 
soils  of  arable  cultivation,  however  they  may  have  arisen — well 
tempered  mixtures  of  sand  and  clay,  not  too  stiff  to  hinder  percola- 
tion and  yet  fine  enough  both  to  retain  water  and  lift  it  by  capil- 
larity. They  also  contain  sufficient  carbonate  of  lime  to  remain 
healthy  and  work  freely.  Several  weeds  are  characteristic  of  these 
soils,  and  are  generally  regarded  as  signs  of  fertile  land  in  good 
cultivation, — such  are  Chickweed  and  Groundsel,  Fat  Hen,  Stink- 
ing Mayweed  and  Sow  Thistle,  the  Speedwells  and  the  small 
Spurges,  Pimpernel,  and  Goose  Grass.  The  typical  tree  of  the 
loamy  soils  is  the  Elm,  while  good  land  is  also  generally  indicated 
by  strong  Hawthorn  hedges,  clean  and  free  from  lichen. 

On  the  low-lying  alluvial  soils  spots  can  often  be  found  where 
either  through  insufficient  drainage  or  the  occurrence  of  springs, 


2i8  THE  BOOK  OF  NATURE  STUDY 

the  level  of  the  ground  water  remains  permanently  near  the 
surface.  When  this  is  the  case  a  deposit  of  peat  or  peaty  soil 
will  begin  to  accumulate,  because  the  stagnant  water  cuts  off 
all  supply  of  air  from  the  soil.  Thereupon  the  roots  and  other 
vegetable  debris  begin  to  decay  in  an  entirely  different  fashion 
from  that  normally  experienced  by  such  material  when  in  contact 
with  air,  as  may  be  seen  by  comparing  a  dead  branch  rotting 
away  on  the  surface  of  the  ground  in  a  wood  with  a  similar  branch 
that  has  been  buried  many  years  in  the  mud  of  a  pond.  The  black 
humus  material  that  forms  from  vegetable  matter  in  the  absence 
of  air  is  generally  acid  in  character,  and  is  accompanied  by  a  deposit 
of  oxide  of  iron,  which  in  peaty  boggy  land  forms  a  thin  film  over 
the  water  of  the  ditches  and  stains  their  banks  with  rust.  Con- 
siderations of  space  will  not  allow  of  any  detailed  account  of  the 
flora  of  peaty  and  boggy  land,  but  a  student  should  attempt 
to  discriminate  between  the  flora  cf  the  acid  true  peat  soils  and 
the  mild  peaty  or  boggy  areas  occurring  where  the  water  is 
naturally  charged  with  carbonate  of  lime. 

THE  PRINCIPLES  OF  CULTIVATION 

In  the  cultivation  of  the  land  the  prime  object  of  both  farmer 
and  gardener  is  the  preparation  of  a  good  seed  bed,  but  what 
constitutes  a  good  seed  bed  is  easier  perhaps  to  feel  than  to  define. 
It  should  consist  of  some  five  or  six  inches  of  friable,  mellow 
soil,  naturally  worked  down  into  fine  grains.  It  should  rest  on  a 
firm  basis  and  be  compact  in  itself,  because  it  contains  neither 
rough  unbroken  clods  nor  large  vacant  spaces.  On  any  but 
the  lightest  soils  the  preparation  of  a  seed  bed  must  begin 
before  the  winter,  by  ploughing  or  digging  up  the  ground  so 
as  to  leave  it  in  a  rough  state  to  the  action  of  the  successive 
frosts  and  thaws.  Even  during  this  preliminary  work  strong 
land  should  not  be  moved  nor  trampled  upon  when  it  is  wet, 
otherwise  the  clay  gets  into  the  puddled  or  tempered  condition, 
whereupon  it  remains  very  sticky  when  wet  and  dries  into  hard 
clods.  The  subsoil  as  well  as  the  soil  should  be  moved,  when- 
ever the  expense  can  be  faced ;  but  on  most  soils  care  should 
be  taken  only  to  stir  the  subsoil  without  bringing  it  up  to 


THE  PRINCIPLES  OF  CULTIVATION  219 

the  surface.  There  is  a  popular  quasi-moral  idea  that  the  good 
soil  lies  below,  and  that  a  little  hardy  spade  work  and  deep 
ploughing  to  bring  it  to  the  top  will  do  wonders  towards  restor- 
ing and  enriching  the  land.  In  the  surface  soil,  however,  rest 
the  sources  of  fertility — the  humus,  which  is  the  chief  store  of 
plant  food,  and  the  bacteria  which  prepare  it  for  the  plant.  If 
they  are  buried  and  so  rendered  unavailable,  years  of  work  and 
manuring  may  be  needed  to  bring  the  subsoil  into  condition, 
and  store  it  with  humus  and  bacteria.  On  clay  land  in  par- 
ticular the  subsoils  are  harsh  and  infertile,  and  may  even  contain 
substances  injurious  to  growth.  It  is  good  to  loosen  and  break 
up  the  subsoil  so  as  to  let  in  the  air  and  destroy  any  pans  just 
below  the  surface,  thus  rendering  it  easier  for  the  roots  of  vegeta- 
tion to  get  down  deeply.  Valuable,  however,  as  a  deep  soil  is, 
it  should  be  deepened  very  gradually  by  setting  the  plough  only 
half  an  inch  or  so  lower  year  by  year.  For  the  same  reasons,  while 
it  is  desirable  that  a  garden  should  be  trenched  over  deeply,  so  as 
to  extend  the  layer  available  for  roots,  in  all  cases  the  surface  soil 
should  be  restored  to  its  old  position  as  the  top  layer.  Subsoiling 
or  trenching  should  be  done  as  early  as  possible,  to  give  the  earth 
time  to  settle  down  again  ;  otherwise,  if  the  subsoil  is  left  open, 
vegetation  will  suffer  from  drought,  because  the  loose  texture  and 
the  many  gaps  break  the  connection  with  the  subsoil  water  and 
hinder  its  capillary  rise  to  the  roots  of  the  crop. 

The  year's  round  of  cultivation  begins,  then,  with  digging  or 
ploughing  before  the  winter,  by  which  means  the  alternate  freezings 
and  thawings  the  soil  experiences  will  not  only  crumble  down  the 
clods  into  a  natural  fine  tilth,  but  will  also  draw  the  finest  clay 
particles  together  and  give  the  soil  a  better  texture.  At  the  same 
time,  the  rough  surface  retains  more  of  the  winter  rainfall,  which 
is  absorbed  and  works  down  into  the  subsoil  instead  of  running 
off,  as  much  of  it  does  when  the  land  is  left  hard  and  trampled  by 
the  removal  of  the  last  crop.  Even  in  Britain,  where  we  may  seem 
to  have  rainfall  enough  all  the  year  round,  it  is  yet  desirable  to 
conserve  as  much  as  possible  for  the  summer  crops,  provided 
that  we  can  get  it  down  into  the  subsoil  and  leave  the  soil  proper 
in  a  reasonably  dry  condition.  Except  in  the  wettest  years  and 
situations,  our  crops  are  more  often  checked  and  reduced  by  a 


220  THE  BOOK  OF  NATURE  STUDY 

want  of  water  than  by  its  excess.  The  weathering  which  a  soil 
receives  by  its  exposure  during  the  winter  in  a  rough  condition 
also  helps  to  render  some  of  the  plant  food  more  available,  but 
these  chemical  actions  are  secondary  in  importance  to  the  effect 
upon  the  texture  of  the  soil. 

When  the  year  has  turned,  an  early  opportunity  should  be 
taken  to  move  the  soil,  which  will  have  become  a  little  set  by 
the  beating  of  the  winter's  rains  ;  if  it  is  sandy  or  a  light  loam 
there  need  be  little  delay,  because  a  day  or  two  without  rain  will 
dry  it  sufficiently  for  working,  and  even  if  it  does  get  trampled 
about  a  little,  the  late  frosts  will  easily  bring  it  into  condition 
again.  But  on  the  heavy  soils  and  on  the  pure  clays  it  is  necessary 
to  wait  and  watch  for  an  opportunity  very  carefully,  because 
one  careless  cultivation  when  the  land  is  still  wet  will  easily  undo 
all  the  good  work  of  the  winter's  exposure,  by  tempering  the  clay 
into  a  paste  from  which  it  has  no  longer  a  chance  of  recovering. 
As  soon  as  the  east  winds  begin  such  kneaded  clay  will  dry  into 
the  toughest  lumps,  which  no  amount  of  cultivation  will  ever 
reduce  to  a  proper  seed  bed ;  even  though  they  are  rolled  and 
knocked  into  little  pieces  they  remain  still  hard  and  unkind. 
But  if  the  right  moment  be  caught,  this  first  spring  cultivation 
breaks  up  the  surface  soil  and  leaves  it,  still  perhaps  rather  rough, 
but  lying  loose  upon  the  firmer  unmoved  land  below. 

As  long  as  the  land  is  solid  and  there  is  a  continuity  between 
the  surface  and  the  subsoil  the  top  layer  will  tend  to  remain  wet, 
although  it  may  be  constantly  losing  water  by  evaporation. 
Water  can  always  rise  by  capillarity  through  compact  earth  in 
which  soil  grain  touches  soil  grain  and  the  water  film  is  con- 
tinuous ;  but  after  cultivation  the  loose  earth  that  is  left  on  the 
surface  is  cut  off  from  the  subsoil  water  by  its  imperfect  contact 
with  the  firm  layer  below,  and  can  therefore  begin  to  dry.  At  the 
same  time  as  the  surface  soil  drys  it  becomes  warm  ;  as  long  as 
it  remains  wet  through  its  connection  with  the  subsoil  the  sun's 
rays  does  little  towards  raising  its  temperature,  because  they  are 
spent  in  bringing  about  the  evaporation  of  the  water  instead  of 
turning  to  heat  in  the  soil  itself.  But  not  only  does  the  early 
cultivation  enable  the  surface  to  dry  and  warm,  it  also  saves  the 
subsoil  below  from  losing  its  stock  of  water  by  evaporation.  The 


THE  PRINCIPLES  OF  CULTIVATION  221 

capillary  rise  only  goes  on  as  far  as  the  soil  is  compact,  it  does 
not  extend  to  the  surface  layer,  which,  dry  itself,  is  exposed  to 
the  sun  and  wind;  all  the  loss  that  can  take  place  is  the  small 
evaporation  of  subsoil  water  into  the  interstices  of  the  soil  resting 
upon  it.  Such  a  layer  of  loose  soil,  which,  although  it  may  become 
dust  dry  itself,  serves  as  a  screen  and  protection  against  the 
evaporation  of  the  subsoil  water,  is  often  called  a  "  soil  mulch," 
because  it  serves  the  same  purpose  as  the  mulches  of  straw  or 
leaves  or  grass  clippings  used  by  a  gardener.  Soil  mulches  become 
of  increasing  importance  as  the  season  advances  and  evaporation 
increases  with  the  higher  temperatures  and  the  longer  days ;  it  is 
the  function  of  the  hoe  to  establish  and  maintain  such  mulches. 

The  remaining  acts  of  husbandry  in  spring  are  all  directed 
towards  making  the  seed  bed,  the  number  of  cultivations  necessary 
being  determined  by  the  fineness  of  the  seed.  The  aim  of  each 
successive  cultivation  is  to  work  the  soil  down  into  a  finer  condi- 
tion, to  get  it  more  and  more  compact  below,  yet  to  leave  a  fine 
layer  of  loose  material  on  the  surface.  Below  the  loose  layer  the 
soil  must  be  both  fine  and  compact  and  rest  firmly  on  the  subsoil, 
otherwise  the  rise  of  subsoil  water  by  capillarity  will  be  slow 
and  imperfect  and  the  crop  will  suffer  from  drought ;  it  must 
also  be  fine,  or  the  small  seeds  will  be  buried  at  all  sorts  of  depths, 
so  that  some  will  be  dried  up  before  they  make  roots  and  others 
will  be  exhausted  before  they  can  reach  the  surface.  The  top  inch 
or  two  of  soil — the  soil  mulch — must  be  kept  loose  and  powdery 
to  protect  the  rest  from  evaporation  ;  its  value  may  easily  be  seen 
by  treading  firmly  in  a  few  places  on  a  newly  made  seed  bed. 
After  a  day  or  two  the  footprints  will  become  and  remain  visibly 
damper  than  the  rest  of  the  land,  so  that  they  must  be  suffering 
a  constant  loss  of  water.  It  is  at  this  stage — the  preparation  of 
the  seed  bed — that  the  skill  of  the  farmer  and  gardener  most 
shows  itself ;  by  experience  he  knows  just  the  right  stage  and 
wetness  or  dryness  when  cultivation  will  be  effective, — a  little 
too  wet  and  on  strong  land  the  result  would  be  disastrous  for  the 
rest  of  the  season,  a  little  too  dry  and  the  clods  will  not  crumble, 
so  that  the  labour  is  wasted. 

When  the  sowing  stage  is  reached  and  the  seed  has  been  put 
in  and  covered  at  its  appropriate  depth,  the  next  operation  is 


222  THE  BOOK  OF  NATURE  STUDY 

generally  to  roll ;  indeed,  if  the  weather  remains  dry,  rolling  is 
generally  repeated  at  intervals  until  the  plant  is  up  and  for  a 
little  time  after.  The  object  of  rolling  is,  of  course,  to  consoli- 
date the  land,  especially  the  surface  layer,  a  condition  which 
facilitates  the  rise  of  water  from  the  subsoil  until  it  is  brought  up 
to  the  very  surface  which  has  been  made  firm  and  smooth.  Con- 
sequently there  is  loss  by  evaporation,  accompanied  by  a  little 
cooling  due  to  the  evaporation,  but  these  two  disadvantages 
have  to  be  faced  in  view  of  the  necessity  of  maintaining  a  proper 
supply  of  water  for  the  small  seeds  or  tiny  seedlings.  The  plant 
is  at  the  most  critical  stage  of  its  existence,  and  everything  must 
be  done  to  keep  it  going,  even  though  the  waste  of  subsoil  water 
may  be  disproportionate  to  the  growth  at  the  time.  In  gardens 
it  is  often  possible  to  check  the  evaporation,  which  is  most  intense 
during  the  strong  easterly  winds  and  bright  sun  occurring  in 
most  of  our  springs,  by  erecting  wind  screens  or  even  by  strew- 
ing a  few  light  fir  boughs  and  the  like  over  the  seed  bed.  In  dry 
wind-swept  districts  it  is  astonishing  to  see  the  marked  benefit 
that  young  vegetation  derives  from  even  the  most  trifling  wind- 
break. As  soon,  however,  as  the  plants  are  well  above  ground, 
hoeing  should  begin,  so  as  to  establish  a  mulch  and  save  the  loss 
of  water  and  consequent  cooling  from  all  the  unoccupied  land 
between  the  plants.  This,  indeed,  constitutes  the  routine  of 
cultivation  for  the  rest  of  the  season,  to  maintain  the  firmest 
possible  soil  round  the  roots  of  the  plant,  and  to  keep  renewing 
the  loose  surface  mulch  with  the  hoe.  An  old  gardener  used  to 
say  that  he  watered  his  plants  with  a  hoe,  and  indeed  if  the 
cultivation  is  only  good  enough,  artificial  watering  will  rarely 
be  needed.  In  one  sense  many  gardens  are  over  cultivated ; 
it  is  never  necessary  to  trench  the  soil  deeply  every  year  or  even 
every  other  year;  to  do  so  only  results  in  a  loose  condition  of 
the  subsoil,  from  which  the  crops  will  begin  to  suffer  in  the 
shortest  drought.  The  commonest  fault  to  be  seen  in  the 
management  of  the  soil  in  gardens  is  this  over  looseness  of  the 
subsoil  as  distinct  from  the  loose  mulch  on  the  surface.  A  gardener 
will  sometimes  show  you  with  pride  that  he  can  thrust  his  stick 
in  his  beds  up  to  the  handle, — it  has  all  been  waste  of  labour 
that  has  left  things  worse  than  they  were  before,  waste  only  to 


THE  PRINCIPLES  OF  CULTIVATION  223 

be  repaired  by  more  waste  in  the  shape  of  copious  waterings 
whenever  a  dry  spell  comes.  Watering,  however,  cannot  always 
be  avoided,  but  whenever  necessary  it  should  be  thorough  ;  a 
little  sprinkling  only  brings  up  the  capillary  film  of  subsoil  water 
to  the  surface  and  increases  the  loss  to  the  soil  in  consequence — 
what  is  necessary  is  a  good  soaking  to  renew  the  stock  of  subsoil 
water.  Then  a  mulch  should  be  strewn  over  the  wet  ground  or, 
on  the  next  day  as  soon  as  the  surface  is  dry,  the  hoe  should  be 
set  to  work  to  establish  a  soil  mulch  and  save  the  water  that 
has  been  added  from  evaporation  except  by  way  of  the  plant. 

One  last  point  in  connection  with  management  calls  for  a 
little  discussion  of  principles,  and  that  is  the  protection  of  some- 
what tender  plants  against  frost.  The  actual  degree  of  cold 
attained  in  this  country  is  rarely  in  itself  sufficient  to  kill  a  plant 
like  a  Tea-Rose, — the  plant  does  get  killed  sometimes,  but  it  is 
by  drought  rather  than  by  cold  If  there  is  a  covering  of  snow 
to  keep  the  plant  in  a  moisture-laden  atmosphere  (and  even  at 
temperatures  below  the  freezing-point  snow  is  always  evaporating 
and  giving  off  moisture)  the  plant  rarely  suffers,  however  low  the 
temperature  may  sink.  Below  the  snow  the  plant  remains  sound, 
but  the  real  mischief  is  done  when  a  strong  drying  wind  blows  over 
a  frozen  ground  unprotected  by  snow.  When  the  soil  is  at  or 
near  freezing-point  the  plant's  roots  cease  to  take  in  any  water,  so 
that  if  evaporation  is  at  the  same  time  going  on  from  the  surface 
of  the  stems  and  branches  there  is  nothing  to  repair  the  loss, 
and  the  plant  may  dry  up  completely  and  be  killed.  In  the 
same  way  the  sun  is  said  to  hurt  a  frozen  plant  by  thawing  it 
too  quickly  ;  it  is  not  the  thawing  that  does  any  harm,  it  is  the 
additional  drying  effect  of  the  sun  when  the  plant  is  already 
almost  without  sap,  and  when  the  roots  are  still  too  cold  to 
bring  in  any  water  from  the  soil.  In  protecting  plants  for  the 
winter  the  great  thing,  then,  is  to  shelter  them  as  much  as 
possible  from  the  drying  effects  of  the  wind ;  plants  cannot  be 
made  appreciably  warmer,  however  much  they  may  be  wrapped 
up,  but  wind  screens  made  of  spruce  branches,  bracken,  even  dead 
leaves  and  loose  straw,  will  check  the  dangerous  evaporation 
caused  by  either  wind  or  sun.  If  the  conditions  get  very  bad,  or 
if  a  cherished  plant  still  unprotected  gets  frozen  and  the  sun 


224  THE  BOOK  OF  NATURE  STUDY 

comes  out,  bravely  syringe  it  with  water  and  bundle  some  loose 
stuff  into  its  dripping  head,  for  the  same  reasons  as  a  nursery- 
man advises  that  a  bundle  of  plants  which  come  to  hand  in  a 
frozen  condition  should  be  soaked  with  water  and  then  buried. 

It  is  impossible  to  do  more  than  indicate  the  principles  that 
underlie  some  of  the  main  operations  of  the  farmer  and  the 
gardener  ;  the  important  thing  to  realise  is  that  some  reason 
generally  exists  for  practices  that  are  the  outcome  of  experience 
and  traditions  that  extend  back  to  Adam.  It  is,  however,  neces- 
sary to  distinguish  between  the  undoubted  secular  tradition  and 
occasional  errors  and  misinterpretations  which  obtain  a  wide 
currency  because  of  their  plausibility  or  the  authority  of  their 
originator.  Both  kinds  of  opinion  claim  to  speak  with  the  weight 
attaching  to  the  practical  man  who  knows ;  to  form  a  judgment 
it  is  necessary  to  reason  out  which  of  the  two  conflicting  views 
best  fits  in  with  the  general  scheme  of  knowledge.  The  cultivator 
who  has  at  the  back  of  his  mind  the  few  broad  principles  we 
have  indicated  about  the  movements  of  water  in  the  soil,  the 
relations  of  root  extension  to  the  water  in  the  soil,  and  of 
evaporation  to  cooling,  will  be  able  continually  to  rationalise  his 
observations  in  the  field  and  garden,  and  will  little  by  little 
become  able  to  piece  them  into  a  scheme  consistent  both  with 
itself  and  with  the  experience  of  others. 


END    OF   VOL.   V. 


Printed  by  MORRISON  &  GIBB  LIMITED,  Edinburgh 


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