CLhc il. il i^ill Xibranj
^.'ovlll (inrnliiia ^iatr Qlnlicc\
5D371
534
SOI 948786 0
hl^ny^
This BOOK may be kept out TWO WEEKS
ONLY, and is subject to a fine of FIVE
CENTS a day thereafter. It is due on the
day indicated below:
OCT 2 1196^
NOV 5 »y^^
SCHLIOH'S
MANUAL OF FORESTRY.
SCHLICH'S
MANUAL OF FORESTEY,
VOLUME II.
SYLVICULTUPvE.
W. SCHLICH, Ph.D.,
C.I.E., F.E.S, F.L.S.,
PRINCIPAL PROFESSOR OF FORESTRY AT THE ROYAL IMDIAX ENGINEERING COLLEGE,
COOPERS hill; LATE INSPECTOR-GENERAL OF FORESTS TO THE GOVERN-
MENT OF INDIA; HONORARY PROFESSOR OF FORESTRY AT THE ROYAL
AGRICULTURAL COLLEGE, CIRENCESTER.
THIRD EDITION. REVISED.
WITH 87 ILLUSTRATIONS.
LOXDOX :
BRADBUEY, AGNEW, & CO. Ld., 10, BOUVEEIE STREET.
1904.
BRADBURY, AONEW, & CO. LD., PRINTERS,
LONDON AND TONBRIDOE.
TABLE OF CONTENTS.
PAGE
INTRODUCTION 1
PART I.— THE FOUND ATIONS OF SYLVICULTURE . 3
Chapter I.— Locality in Relation to Forest Vegetation . . 7
Section I. — The Atmosphere ....... 8
Section II. — Climate 11
1. Heat 12
2. Light 17
3. Moisture 20
4. Air Currents 22
Section JII.— Soil 23
1. Origin of Soil 24
2. Formation of Indigenous Soil . . . . . 24
3. Composition of Soil . . . . . . . 26
4. Physical Properties of Soil ...... 29
5. Classification of Soils . . . . . . . 31
Sectimi IV. — Effect of the Soil upon Forest Vegetation . . 34
Section V. — Effect of Forest Vegetation upon the Locality . . 41
Section VI. — Assessment of the Quality of the Locality . . 45
Chapter II. — Development of Forest Trees 52
1. Shape 52
2. Height Growth 54
.3. Diameter Growth 57
4. Volume Growth 59
5. Duration of Life 62
6. Reproductive Power 64
Chapter III. — Character and Composition of Woods . . 69
Sectimi I. — Pure Woods 69
Section II.— Mixed Woods 71
1. Advantages of Mixed Woods 71
2. Disadvantages of Mixed Woods 73
3. Rules for the Formation of Mixed Woods . . . 74
4. Mixtures of Shade-bearing Species . . . .77
5. Mixtures of Shade-bearing with Light-demanding
Species . . . . . . . • . . 79
6. Mixtures of Light-demanding Species . . .85
39925
VI TAIU.K or CONTENTS.
PAGK
Chapter IV.— Thk Sylviccltur.'VL Svstkms, or Mkthods of
Tkkatmknt 89
Section I. — Description of Systems ...... 90
1. Clear Cutting ill High Forest 90
2. The Shelter-wood Compartment System . 9-3
3. The Shelter-wood Group System 94
4. The Shelter-wood Selection System . . .96
5. The Coppice System 97
G. The Coppice with Standard System . . 99
7. High Forest with Standards 102
8. Two-storied High Forest 103
9. High Forest with Soil-protection Wood . . 104
10. Forestry Combined with the Growing of Field Crops . 104
11. Forestry Combined with Pasture 107
12. Forestry Combined with the Rearing of Game . . 107
Section //.—Choice of System 107
PART II. FORMATION AND REGENERATION OF WOODS. 113
Chapter I.— riacLiMiNAiiv \VoiiK.s 116
Section I. — Choice of Species 116
Section //.—Fencing 122
Section III. — Reclamation of the Soil 129
1. Treatment of an Impermeable Substratum . . 130
2. Treatment of Swampy Ground Generally . . . 131
3. Irrigation of Arid Land 137
4. Treatment of Excessive Accumulations of Vegetable
Matter 138
5. Fixation of Shifting Sands 139
6. Fixation of Unstable Soil on Slopes .... 143
Chapter II.— Artificial Formation of Woods 145
Section I. — Direct Sowing 145
A. Conditions of Success 145
1. Choice of Species 145
2. Quality of Seed 145
3. Quantity of Seed 149
4. Conditions of Germination . . ]51
B. Methods of Sowing 157
1. Broadcast Sowing 157
2. Partial Sowing 162
Section //.-Planting 169
A. Conditions of Success 169
1. Choice of Species . . . ,170
2. Different Kinds of Plants 170
3. Quality of Plants .171
4. Age and Size of Plants 172
TABLE OF CONTENTS. Vll
Chapter II. — continued. page
Section II. — Planting — continued.
A. Conditions of Success — continued.
5. Season for Planting ....... 173
6. Density of Planting 174
7. Distribution of Plants over the Area . . . . 175
8. Number of Plants 181
9. Lifting Plants 183
10. Pruning Plants 186
11. Protection of Plants in Transit ..... 188
12. Preparation of the Soil ...... 190
B. Raising Plants 190
1. Purchase of Plants 190
2. Plants taken from Existing Woods . . . . 191
8. Raising Plants in Nurseries 192
C. Methods of Planting 208
1. Planting with Balls of Earth 210
2. Planting without Balls of Earth 211
3. Mound Planting 2] 9
D. Planting of Slips, Layers and Suckers ..... 220
Chapter III. — Natural Regeneration of Woods .... 223
Section I. — Natural Regeneration by Seed 223
A. Natural Regeneration under Shelter- woods . . . 223
1. The Compartment or Uniform System . . . . 225
2. The Strip System 237
3. The Group System 239
4. The Selection System 243
5. Comparative Merits of the Four Systems . . . 244
B. Natural Regeneration from Adjoining Woods . . . 247
Section II. — Natural Regeneration by Shoots and Suckers . . 250
Chapter IV. — Formation of Mixed Woods 254
1. Formation of Even Aged Mixed Woods . . . . 254
2. Formation of Uneven Aged Mixed Woods . . . 258
Chapter V. — Choice of Method of Formation 261
Section I. — Choice between Direct Sowing and Planting . . 262
Section II. — Choice between Artificial Regeneration and Natural
Regeneration by Seed . . . . . . 266
Section III. — Combination of Several Methods of Formation . 268
PART III.— TENDING OF WOODS 271
Chapter I. — Tending of Woods during Early Youth . . . 276
1. Protection against External Dangers .... 276
2. Preservation of a Proper Density of the Crop . . 278
3. Cleaning of Young Woods 279
4. Preservation of a Proper ^Mixture 280
VI 11 TABLE OF CONTENTS.
PAGE
Chapter II.— Tending of Crowded Woods after Early Age . 281
Section /.—Removal of Dead, Dying, or Otherwise Undesirable
Trees 281
Sectio7i 77.— Pruning 283
Section 777.— Thinning 288
1. General 288
2. The Most Suitable Growing Space 289
.3. The Theory of Thinning 292
4. Thinning of Mixed Woods 296
5. Thinning of Coppice Woods 297
6. Principal Advantages of Thinning 298
7. Execution of Thinnings 299
Chapter III. — Tending of Open Woods for the Production
OF Large Timber 30i)
1. The Theory 390
2. Principal Forms of Treatment 302
3. Execution of the Work 305
PART IV.-SYLVICULTURAL NOTES ON BRITISH FOREST
TREES 307
1. Beech 310
2. Hornbeam 315
3. Oak 319
1. Ash 325
5. Ehn 328
G. Sweet Chestnut 331
7. Maple 334
8. Common Alder 336
9. Birch 340
10. Willow 343
11. Poplar 346
1-J. Lime-tree 349
13. Hazel 351
14. Silver Fir 353
15. Spruce 358
16. Scotch Pine 363
17. Black or Austrian Pine 368
18. Corsican Pine ........ 371
I'J. Weymouth Pine 372
20. Larch 375
21. Douglas Fir 381
INDEX 389
SYLVICULTURE
INTKODUCTION.
Sylviculture literally means the culture of forests, that is
to say, all measures connected with the formation, preserva-
tion and treatment of forests. In practice, however, the word
forestry is used to express and comprise all this, while by
sylviculture, in its narrower sense, is understood the formation,
regeneration and tending of forests, or woods, until they
become ripe for the axe. Sylviculture, in the latter sense,
teaches how a forest, or wood, can be produced and guided to
maturity so as to realise in the most advantageous manner
the object which the proprietor has in view.
The object for which a particular forest is maintained
depends on the will and pleasure of the owner, in so far as his
freedom of action is not limited by rights of third persons, or
by legal enactments. The object itself can be one of many,
and of these the following may be mentioned by way of
illustration : —
1. To yield produce of a definite description, for instance trees
and shrubs of special beauty, or trees giving a certain
kind of timber, or other produce, fit for particular
purposes, such as grass, turpentine, caoutchouc, etc.
2. To produce the greatest possible quantity of wood, or
other produce, per acre and year.
3. To produce the highest possible money return per acre
and year.
4. To produce the highest possible interest on the invested
capital.
5. To produce certain indirect eft'ects ; for instance, to
s. K
Library
_ N. C. St-Lt.(- OollfiiT..
2 INTRODUCTION.
influence the climate, to regulate the drainage of the
country, to prevent landslips or avalanches, to arrest
shifting sands, etc.
In each of these and other eases the particular species of
tree to be grown and the method of treatment are likely to
differ, and it is the business of the forester to select those
species and methods which realise the object of management
most fully and in the most economic manner. More especially,
the forester must always consider what effect the species and
the selected method of treatment are likely to have on the
property, and he must remember that any exceptional strain
put upon the soil for more than a limited period, in order to
realise an exceptional effect, must be followed by a corre-
sponding period of relaxation. Unless this is given, the soil,
in the majority of cases, will deteriorate, and it may ulti-
mately become absolutely sterile. Such an exceptional strain
may suit the special requirements of a particular owner, but
is not in the interest of the general community. Political
Economy teaches, that the correct mode of procedure points to
the careful preservation of the productive powers (or factors)
of any given locality, so as to render possible the production of
the same effect, or an increased one, regularly and indefinitely.
Experience has shown that in forestry the safest method of
preserving the productive powers of a locality consists in
maintaining uninterruptedly a crop of forest vegetation on the
area. The more frequently and the longer the ground is
uncovered and exposed to the full effects of sun and air
currents, the more, in the majority of cases, is the productive
power liable to be reduced.
The subject of Sylviculture will be treated under the
following headings : —
Part I. — The Foundations of Sylviculture.
II. — Formation and Regeneration of Woods.
,, III. — Tending of Woods.
TV.— Sylvicultural Notes on British Forest Trees.
PAKT I.
THE FOUNDATIONS OF SYLVICULTURE.
b2
THE FOUNDATIONS OF 8YLYICULTUEE.
The natural forest vegetation of the various parts of the
earth consists of a large number of species of trees and shrubs,
each of which has its peculiar mode of gro\Yth, and thrives
best under certain conditions. Only a limited number of
species of trees possess the faculty of forming by themselves
healthy and flourishing woods, ^Yhile others will obtain perfec-
tion only if they are mixed with the former. Species are
called ruling, or dependent, according to whether they belong
to the first or second category. Owing to the great number of
species and the ever-changing conditions in different parts of
the earth, it would be altogether impracticable to deal with all
in a book which has for its object to teach the theory of sylvi-
culture. The general principles of sylviculture hold good all
over the world, but the illustrations must be taken from a
limited area. In the present volume they will be taken chiefly
from the timber trees ordinarily growing in Western Europe
on the fiftieth degree of northern latitude, and the countries
immediately to the north and south of it. If the more
important species of timber trees growing in that region are
classified in accordance with what has been said above, the
following lists are obtained : —
Riding Species.
Decidedly ruling. — Silver fir, beech, spruce, Scotch pine.
Conditionally ruling. — Hornbeam, oak, larch, common alder,
birch, willows, Austrian pine, mountain pine, Weymouth
pine, Douglas fir.
Dependent Species.
Of these may be mentioned : Ash, Norway maple, sycamore,
sweet chestnut, poplars, elms, lime, white alder, Cembran
pine, etc.
6 THE FOUNDATIONS OF SYLVICLLTUllE.
Althougli the biological characteristics of these and other
species have been carefully studied for many years past, the
subject has been by no means exhausted, because the factors
which affect the growth of trees vary constantly, and moreover
some of these factors are as yet imperfectly understood. The
experience so far gathered will be found in the succeeding
chapters. It is that experience which must guide the forester
in the selection of species for a particular locality, and of the
subsequent method of treatment.
The subjects which claim more immediate attention will be
dealt with in the following four chapters : —
Chapter I. — Locality in Relation to Forest Vegetation.
,, II. — The Development of Forest Trees.
,, III. — Character and Composition of Woods.
,, IV. — The Sylvicultural Systems.
These are matters which govern all forest operations, not
only the formation, regeneration, and tending of woods, but
also the determination of the yield, the preparation of working
plans, and the ultimate utilisation of the forest produce.
CHAPTEE I.
LOCALITY IN RELATION TO FOREST VEGETATION.
When a plant germinates on the surface of the earth, it
sends its roots into the soil, and its stem into the air. The
soil, assisted hy the subsoil, provides to the plant the means of
stability and nourishment ; the atmosphere overlying the soil
furnishes certain nourishing substances, heat, light, and
moisture. Hence soil, including subsoil, and atmosphere are
the media which act upon forest vegetation, and they together
are in sylviculture called the " localiti/." The active agencies
or factors of the locality depend on tjie nature of the soil and
the climate, the latter being governed by the situation. The
sum total of these factors represents the quality or yield capa-
city of the locality. The forester requires to be well acquainted
with the manner in which soil and climate act on forest vege-
tation, in order to decide in each case which species and method
of treatment are best adapted, under a given set of conditions,
to yield the most favourable results. The detailed considera-
tion of the laws which govern this branch of forestry finds a
place in the auxiliary sciences, such as Physics, Chemistry,
Meteorology, Mineralogy, and Geology. A sufficient know-
ledge of these branches of science is assumed, so that here
only their application to Sylviculture need be considered.
The chapter has been divided into the following sections : —
Section I. — The Atmosphere.
,, II. — Climate.
III.— Soil.
,, IV. — Eliect of the Locality on Forest Vegetation.
,, V. — Effect of Forest Vegetation on the Locality.
,, VI. — Assessment of the Quality of the Locality.
8 LUCALITY AND FOKEST VEGETATION.
Section I. — Tiik Atmosphere.
The earth is surrounded by gaseous bodies, which move
with it, and collectively are termed the atmosphere. Owing
to the weight of its component parts, the atmosphere is densest
close to the surface of the earth, and l)ecomes tliiimer with
increasing distance from the earth passing gradually into space.
The atmosphere consists essentially of the following
substances : —
(1.) Oxygen and Nitrogen.
(2.) Carbon dioxide.
(3.) Water, in various conditions.
(4.) Solid bodies.
(5.) Ammonia and Nitric Acid.
1. O.rijficii (iinl Xili'Dficii.
The chief constituents of the atmosphere are 21 parts of
oxygen and 79 parts of nitrogen in a mechanical mixture, as
well as small quantities of argon, helion, and other substances.
The latter have quite lately been discovered, and it would
be beyond the scope of this book to discuss them licrc. No
chemical process is required to separate oxygen from nitrogen ;
as a matter of fact, all porous bodies possess the faculty of
taking oxygen from the atmosphere, without entering into a
chemical combination with it. Amongst such bodies are the
soil, leaves, bark, and roots of plants. Until a comparatively
late date it was believed that plants could not take nitrogen
direct from the air. It has now been proved tliat certain
plants, including various forest trees, can do this, and further
investigation will doubtlessly lead to additional discoveries in
this respect.
Although tlie leaves of plants take up oxygen, tliey exhale
greater quantities of it under the effect of light ; the latter is
the result of the decomposition of carbon dioxide by the
leaves, which retain the carbon and surrender the oxygen.
Thus, plants are powerful agents in the productit)n of oxygen.
THE ATMOSPHERE. 9
The action of the air in the soil is chiefly two-fold ; it causes
the evaporation of moisture, and the decomposition of organic
matter. The air which penetrates into the fissures and inter-
stices of the soil becomes laden with vapour and carbon
dioxide ; it is then forced out of the soil b}' every rise of
temperature, and replaced bj^ fresh air during cooling. The
extent of this change of air depends on the degree of porosity
of the soil and the daily range of temperature ; the greater
these are, the more rapidly will moisture and organic matter
(humus) disappear. The daily range of temperature is
seriously affected by the degree of protection which the soil
receives from forest vegetation ; it is greatest in fully exposed
soils and smallest in soils under the shelter of a crowded
crop of trees, especially if the foliage offers lateral as well as
vertical shelter against sun and air currents. In the latter
case the humus is generally carefully preserved, in the former
it disappears rapidly.
2. Carhon Dioxide.
About 0*0004 parts of the volume of the atmosphere
consist of carbon dioxide, which is received from a variety
of sources, as combustion or decomposition of plants, the
breathing of animals, volcanoes, spring water issuing from the
interior of the earth, combustion of coal and lignite, from
various minerals, as for instance calcium carbonate. Of these,
the first is by far the most important source of supply.
Plants, except certain parasites and saprophytes, take the
carbon dioxide which they require through their leaves from
the atmosphere. Subsequently, when they die and are decom-
posed, their carbon is converted back into carbon dioxide, and
returned to the atmosphere ; hence plants form an important
link in the movement of carbon dioxide.
3. Moisture.
The atmosphere is the medium through which the dry
land receives the greater part of the necessary moisture.
10 LOCALITY AND FOIIKST VJ-KiKTATlOX.
Sheets of water (the sea, lakes, rivers, etc.) and moist bodies
evaporate moisture, which, as vapour, rises in the atmosphere,
until it is again condensed into water. It either settles as
dew on cool objects, or falls as rain, snow, or hail from the
cloud region to the ground. Plants, being moist bodies, take
part in the circulation of moisture ; they receive it from the
soil through the roots, and evaporate it through the leaves.
In this perpetual circular motion of moisture, several points
are of special interest to the forester. By the action of
heat water is converted into vapour, and consequently
evaporating bodies become drier and cooler, and reduce the
temperature of the surrounding layers of air in their effort
to replace the expended heat. It follows that the rate of
evaporation is, amongst other influences, governed by the
temperature, which depends upon the climate. There is, how-
ever, another reason why the rate of evaporation depends on
the temperature : — The maximum of vapour which saturated
air can hold rises at a more rapid rate than the increase in
temperature. If, for instance, one cubic foot of air is saturated
with vapour when it contains "15 grams of water at freezing
jjoint (32^ F.), it can hold "28 grams at a temperature of
54^ degrees, and "(U grams at 77 degrees. It follows that air
of a high temperature can hold more vapour than at a low
temperature, and yet the relative, humidity may be smaller in
the former case. Hence evaporation is more rapid in summer
than in winter : it is generally also greater during the day
than at night.
4. Solid JUhUcs.
Tlie atmosphere always contains a certain (juaiitity of
organic and inorganic solid ])odies, which are kept in suspen-
sion in conseijuence of their minute size and lightness. AVhen
vapour is condensed and falls to the ground as rain, snow, or
hail, it carries with it a certain ipiantity of these solid bodies,
which differs according to locality ; the mineral part of these
deposits is not inconsiderable compared with that wliicli
CLIMATE. 11
is required annually for the production of timber on a fully-
stocked area. Amongst the substances thus brought to the
ground are calcium carbonate, magnesium carbonate, sodium
chloride, calcium sulithate, ferric oxide, alumina, silica,
organic nitrogenous matter, etc. Direct analysis has shown
that upwards of 800 lb. of these substances have been
deposited on an acre of land in one year, a quantity more
than sufficient to provide for that contained in a heavy
increment of wood laid on during the same period. In other
cases, observations have shown that the quantities deposited
are considerably less than 300 lb. per acre.
5. Ammonia and Nitric Acid.
Limited amounts of these important substances are con-
tained in the atmosphere ; they supply nitrogen to forest plants
in considerable quantities, especially for the formation of seeds.
A certain quantity of ammonia and nitric acid is brought
into the soil by the annual rainfall ; where the latter is
heavy, the quantity of the above substances thus obtained by
the soil may be sufficient for all the requirements of forest
growth, but where it is light, this will not be the case.
As already stated, certain plants (Leguminosse) can take
nitrogen direct from the air by means of tubercles or nodules,
which are produced by microscopic fungi or bacteria. Again,
further investigation may show that mycorhiza, a coat formed
by a fungus outside or inside the root, is connected with the
assimilation of nitrogen by the plant.
Section II. — Climate.
By climate is understood the local peculiarities of the
atmosphere in respect of temperature, degree of clearness,
moisture and rest or motion. As already indicated, the climate
of a locality depends on its situation.
The climate of a locality is of greater influence upon the life
12 LOCALITY AND FOREST VEGETATION.
and growth of plants than the degree of fertiUty of the soil ;
hence it demands the forester's special attention. Generally
speaking, the climate of a locality depends on : —
(1.) Latitude and longtitude, or geographical position.
(2.) Elevation ahove the level of the sea.
(3.) Aspect and gradient.
(4.) Shape of the surface and condition of surroundings.
Each of these affects the heat, light and humidity of a
locality, which are the agencies determining the commence-
ment and course of the annual phenomena of vegetation.
1. IlcaL
Heat affects plant life in various ways. In the first place,
it is necessary for transpiration h}^ the plants and evaporation
from the surface of the earth ; and secondly, it governs the
movement of the air, which produces a thorough mixture of
its different ingredients, as well as that of warm and cold, dry
and moist, clear and hazy air.
The heat required hy plants for transpiration and growth
must he supplied to them hy the atmosphere, either directly
or througli the soil. If these are themselves deficient in heat,
transpiration must cease as soon as the plant has expended
the store of heat which it contains. The latter, however, fre-
quently does not take place until serious damage has l)een done
to the plant, in other words, the temperature of the plant may
he so far reduced that the freezing point is reached, although
the temperature of the surrounding air is still several degrees
above that point.
The only important source of atmospheric heat is the sun ;
hence the temperature of a locality depends in the first place
on its latiiudc. The mean annual temperature decreases with
the distance from the equator because the sun's rays strike the
earth more obli(juely in proceeding iiorth oi* south from the
equator towards the poles. In the centre of Europe and
in the vicinity of the 50th degree of latitude, the tempera-
ture decreases one degree for ul>uut every Ol miles, on
HEAT. 13
proceeding north. The cHmate thus produced is frequently
called the cieof/rajyliieal or solar climate. It exists practically
nowhere on the earth, because it is modified and converted into
the pJiysical or local climate by a series of influences, amongst
which the following deserve attention : —
a. Elevation above the Level of lite Sea.
The temperature falls with elevation above the sea. In
the Alps the fall is one degree for every 300 to 400 feet of
elevation ; it is about 900 times as rapid as the fall caused by
increasing latitude. The effect of elevation upon temperature
is subject to modifications. High plateaux of considerable
extent show a milder climate than that calculated for their
elevation, because the sun's rays are more intense than at the
level of the sea. On the other hand, wind currents exercise a
considerable effect, so that isolated peaks have, as a rule, a
comparatively rough climate.
Cold air, owing to its weight, glides down slopes and may
become stationary in valleys and low land generally, producing
locally and temporarily a low^er temperature than that which
corresponds to the elevation of the locality. Hence in such
localities late and early frosts are more common than in
localities which are under the influence of a free circulation of
the air.
h. Presence of Extenm'e Sheets of Water.
Owing to a difference of temperature, and the consequent
exchange of air between dry land and sheets of water, the
latter cause the climate of the former to be more equable, the
temperature being lower during the day and higher during
the night. It is chiefly for this reason that the longitude of
a locality, by affecting its distance from the ocean or other
extensive sheets of water, influences the local climate.
c. Aspect and Gradient.
The angle at which the sun's rays strike the soil depends on
the aspect of the locality ; hence, in the northern hemisphere,
aspects between south-east and south-west are the warmest,
14 LOCALITY AND FOREST VEGETATION.
and those between north-east and north-west the coldest. The
de«:,'ree of the gradient further niodilies this effect, which also
depends on the latitude.
The aspect atfects the temperature also in exposing a
locality to air currents, or protecting it against them. This
effect may be favourable or the reverse according to the nature
of the air currents.
(I. Pn-scncf or Absence of Forest Vegelaiioii.
Localities, which are bare of vegetation, are struck In- the
full force of the sun's rays, causing the temperature at the
surface of the soil to rise to the highest possible degree. At the
same time, air currents sweep unimpeded over such localities,
causing a rapid change of the atmosphere.
On localities covered with a full crop of forest vegetation
the sun's rays strike the crowns of the trees ; the heat
absorbed by the air at some height above the ground,
penetrates only slowly through the leaf canopy to the layer
of air belo^Y it and thence to the soil. During the night again
the leaf canopy prevents, or at any rate reduces, radiation.
It follows that the air in forests is cooler during the day and
warmer during the night, than the air on bare localities. This
effect is intensified by the fact that the foliage of the trees
impedes the force of air currents.
Direct observations have established the following facts : —
(1.) The climate of wooded countries is more ecjuuble than
that of open countries.
(2.) The mean temperature of soil and air in wooded
countries is somewhat lower than that of soil and air in
bare countries. This reduction of temperature would
ordinarily act beneficially in warm southern countries, while
it may become injurious in cold northern countries where
the temperature is already lower than is desirable.
(3.) The greatest difference occurs in summer, next in
spring, then in autumn, and it is very small in winter. It
follows that in forests the commencement of vegetation in
HEAT. 15
spring is retarded. This may be beneficial in preventing
damage b}' spring frosts, limiting the formation of inferior
spring wood, etc. ; on the other hand it shortens the growing
season, and delays the sprouting of seeds in spring.*
Heat is a most powerful agency in the distribution of plants
on the earth ; the species change with increasing latitude,
elevation and other influences which govern the temperature.
This applies to forest trees as well as other plants.
Attempts have been made to ascertain the absolute sum of
heat required annually by the more important forest trees,
which have been enumerated in the introduction of this part,
but so far the available data are not of much practical use
in sylviculture. Moreover, it is beyond doubt, that mean
temperatures are much less important to forest trees than
the extremes of temperature which occur in a particular
locality, more especially during the growing season.
Something more definite is known of the relative heat
requirements of the several species. According to Gayer this
is as follows : —
It is (jreatest in : Common elm, sweet chestnut, pedun-
culate oak.
Someichat smaller in : Sessile oak, Austrian pine, silver fir,
beech, Weymouth pine, lime, Scotch pine.
Less again in : Norway maple, birch, sycamore, ash, alder,
hornbeam, spruce.
Smallest in : Larch, Cembran jjine, mountain pine.
The different degrees of heat requirement produce many
phenomena of interest to the forester, of which the following
may be mentioned : —
(1.) On the same latitude the several species, if left to
natural selection, are found at different elevations. While
the Cembran pine finds full development near the ujjper
limit of tree vegetation (up to 7,000 feet in the Alps), the
larch and next the spruce prefer a somewhat lower zone ;
lower again appear beech, silver fir and sessile oak, wliile
* For further details on these questions, see Vohime I.
16 LOCALITY AND FOREST VErTETATION.
tlie pedunculate oak and Scotch pine tlouiisli in the low-
lands.
(2.) A species which jnefers a certain altitude in one
locality, will descend towards the level of the sea with
increasing latitude, or ascend with decreasing latitude.
(3.) At the same altitude, the more heat requiring species
will seek the warmer southern aspects, and the less heat
requiring species the cooler northern ones.
(4.) A species, which is naturally found on a northern
aspect at a low elevation, will seek a southern aspect at a
higher altitude.
It must not, however, be overlooked, that the actual dis-
tribution is affected by many other influences besides heat,
and that the above theories are only of an abstract nature.
The effect of frost on the various species is intimately
connected with their heat requirement. Trees suffer, as a
rule, little from winter frosts within the region of their
natural distribution, but frost which occurs during the
growing season may do considerable damage ; especially
during spring (late frosts), immediately after the tender
leaves and shoots have been put forth, and during autumn
(early frosts), before the newly-formed wood has had time to
ripen. Many influences and circumstances contribute towards
the occurrence of late and early frosts. Sometimes they are
caused locally, especially in low lying or confined localities in
consequence of excessive radiation, evaporation, the descent
of cold air from higher localities, and absence of air currents ;
in other cases they are due to cold winds. The several species
vary much in their bearing towards late and early frosts ; in
a general way the following classification will hold good : —
Most sulijtrt to suffer from laic aud carlij frosts arc : Ash,
acacia, sweet chestnut, beech, silver fir.
Somewhat less : Oak, Douglas fir, Norway maple, sycamore,
spruce, alder.
Least: Lime, hornbeam, elm, birch, larch, aspen, Corsican,
Ausli-ian, Weymouth, and Scotch pines.
LIGHT. ]7
The degree of damage depends, apart from the severity of
the frost, on the condition of the leaves and yomig wood, the
general health and vigour of the plants, and whether they
have been suddenly or gradually deprived of shelter.
The damage occurs, generally, during the process of thawing
after freezing. The more rapidly the plant thaws, the greater
will be the damage ; hence it will be greatest on east and
south aspects, and smallest on west and north aspects.
Frost may kill the plant outright, or only the leaves and
tender shoots. It may also cause cracks in the bark, as in
beech, or in the bark and wood, as in oak.
2. Lifjht.
The earth receives light from the sun, the source whence
heat is supplied. With the exception of certain low forms,
all plants require light to enable them to live and grow, as
soon as the available reserve materials have been consumed.
Without light carbon dioxide cannot be decomposed by the
chlorophyll of the plants.
During the process of germination light is not required,
because the embryo is developed by means of substances
deposited in the seed. Similarly, the first starting of vege-
tation in spring can take place with a small amount of
light, because it is done by means of reserve materials
deposited in certain parts of the plant. As soon as these
substances, both in germination and the awakening of
vegetation in spring, have been consumed, light becomes
absolutely necessary for the preparation of new food
materials.
All trees, then, require light for their proper development,
but the necessary quantity has its upper and lower limit.
Not only too little but also too much light can interfere
with the phenomena of growth. Between the maximum and
minimum a degree exists which corresponds with the most
favourable development of a species, and which represents its
normal light requirement. Eegarding the absolute quantity
18 LOCAI.ITY AND Fdl^HST VEGETATION.
of lifiht required by the several species little is known at
present, but much experience has been collected which
demonstrates their relative light requirements. On 'the
whole it is known that certain species cannot thrive unless
the.v enjoj' a large measure of light throughout life, while
others will bear a certain amount of shade. Accordingly,
the former species are termed lijiht dcinandhui, and the
latter sliade hcariuii or tolrnitiiif/. In a general way it may
be said, that trees with a dense crown are shade Ijearing,
and those with a thin crown light demanding, though the
light requirement does not always stand exactly in inverse
proportion to the density of the crown.
Some species, which are shade bearing, require a certain
amount of shelter, or protection, during early youth ; they
have therefore been called " shade demanding." Such a
definition is, however, misleading, as these plants require
protection against heat and cold, and not against light as
such. In young plants of beech and silver lir, for instance,
transpiration frequently reaches such a high degree, if they
are not sheltered, that they lose water more quickly than
they can take it up from the soil, and consequently die.
Hence they require either a thorough wetting of the soil,
or shelter. In tlie former case more water is availal)le,
and in the latter the temperature and thereby the transpi-
ration is reduced. Species are called tender or luirdi/,
according as to whether they require shelter during early
life, or can do without it.
By summing up the available experience of the light
requirements of a number of species, scales have been
prepared by various authors, which, though generally agree-
ing, differ somewhat in details. The following scale begins
with the most light demanding species and finishes with the
most shade bearing. Lime and Weymouth pine stand in the
centre of this scale; the species above them are considered
light demanding, and those below shade bearing, the degree
in each case depending on the distance from the centre line.
LIGHT. 19
(1.) Larch, birch.
(2.) Scotch pine, aspen, willows, Corsican pine.
(3.) Oak, ash, sweet chestnut, mountain pine.
(4.) Elm, common alder, Austrian pine.
(5.) White alder, lime, Weymuutli pine, Norway maple,
sycamore, Cembran pine, hazel, Douglas fir.
(6.) Spruce, hornbeam.
(7.) Beech.
(8.) Silver fir.
(9.) Yew.
The above scale represents only general averages. In reality
the degree of light requirement is subject to considerable
modifications caused by the peculiarities of each locality.
Generally, all species bear more shade on good fresh soil
than on poor dry ground, a fact which is indicated by the
density of the crown. The Scotch pine, for instance, grown
in fresh soils in countries near the sea looks quite different
from the same tree seen in continental countries, and stands
considerably more shade than the latter.
The length of the growing season also influences the
degree to which a tree will stand shade. A certain total
quantity of light is required to complete the annual cycle of
development, hence a more energetic effect of light is wanted
in localities with a short growing season, such as high eleva-
tions, or high latitudes. A species which stands a certain
amount of shade at the level of the sea and in a southern
climate, may become light demanding at a considerable
elevation, or in a northern climate. Again, in foggy air,
under a usually covered sky, or on northern aspects, the
same species stands less shade than in usually clear air,
under a sunny sky, or on southern aspects. In this respect
it must be remembered that the actual intensity of the light
is somewhat greater in high mountains than in low lands.
The health of the trees is also of importance. Strong
healthy plants with a good root system stand more shade,
and for a longer period, than weak plants.
c2
SiO LOCALITY AND FOREST VEGETATION.
Lir!;ht and sliade in relation to tree growth are of the
greatest importance in practical sylviculture, especially in
the regeneration and tending of woods, the composition of
mixed woods, etc. In each of these cases the light require-
ment of the species must be fully considered, or serious
mistakes may be made. The most important period in this
respect is early youth, because at that time several species
require some shelter, either against heat or frost. If that
shelter, on the other hand, is excessive the young trees may
be permanently injured, or even die. When a plant has stood
in shade for some time, the activity of its leaves is reduced,
and it takes some time, after the removal of the shelter, before
the increased light produces increased assimilation and visible
activity, because fresh organs, fitted for the altered conditions,
must be produced. In all such cases it is best to remove the
cover gradually and not all at once. If the plant has stood in
shade for a considerable period, it may be no longer capable of
developing into a tree of normal size. As long as several
strong buds are found, especially near the top, this is not to
be feared, but the recovery of plants witli a few miserable
buds may be considered as hopeless.
8. Moisture.
The Ih-st question for consideration is, whether moisture in
the air is directly necessary or beneficial to plant life. The
investigation of this problem meets M'ith great difiiculty,
because it is often difficult to separate the effect of air
moisture from that of' soil moisture. As a matter of fact,
only meagre data are available as far as trees are concerned.
It is known that some species, such as spruce, alder, maple,
ash, and next to these, silver fir, beech and birch, thrive
generally better in moist than in dry air. It is also a fact,
that spruce appears naturally over extensive areas in high
situations and near the sea shores of northern Europe, that
is to say, in localities with a comparatively moist air, while
MOISTURE. 21
it thrives but indifferently in continental situations with a
dry air. The Scotch pine, on the other hand, appears over
extensive tracts in continental dry climates, and at the
same time flourishes in the moist insular climate of Great
Britain.
Although further investigation is necessary to show whether,
or to what degree, trees take up moisture through their organs
above ground, the atmospheric moisture is of the highest
importance, for the following two reasons : —
(a.) It governs the degree of transpiration from the leaves
of the trees.
(b.) It supplies the soil with water, whence it is taken up by
the roots of the trees.
Apart from the temperature, the degree of transpiration
depends on the degree of saturation of the air ; hence
relatively dry air causes rapid transpiration, while the latter
ceases as soon as the air becomes saturated. The degree
of transpiration, in its turn, governs the rapidity with which
fresh water laden with raw materials is taken up by the
roots.
The soil receives water from the atmosphere in the shape of
precipitations, as dew, rain, snow, hail, and a certain amount
by means of its hygroscopic nature. The quantities differ
enormously in different climates and localities, from almost
nothing to over 500 inches a year. Precipitation cannot take
place unless the air becomes saturated. The phenomena
which favour an increase in the relative humidity, and thereby
induce saturation, are active evaporation and a reduction of
temperature. On the one hand, evaporation causes a reduc-
tion of temperature, and on the other a falling temperature
reduces the degree of evaporation ; the result is, that saturation
and precipitation occur only locally.
As a general rule a low temperature means a high degree of
relative humidity ; hence the latter is greater in winter than
in summer; greater at high elevations than in low lands;
greater in the vicinity of extensive sheets of water than in
22 LOCALITY AND FOREST VROETATION.
contiiK'iitiil {'ouiitries ; n;reater in forest countries than in l»are
tracts.
Direct observations have shown that the rehxtive liuniidily
of forest air is greater than that of open air, the difference
amounting in Central Euroi:)e to as much as 10 per cent,
during summer, and a])Out lialf that amount in winter. The
practical vahie of this fact in sylviculture is, that radiation of
heat is much slower in moist than in dry air; hence tlie
danger of late and early frosts is smaller in the former than
in the latter.
Snow and ice have a considerable effect upon trees. During
early youth snow may protect forest plants against excessive
cold. Afterwards a heavy fall of snow, or the formation of
ice or rime, may break the branches and tops of trees, or even
fell them to the ground.
4. Air Currents.
The atmosphere is, practically, in constant motion. The
principal cause of this is the uneven heating of the earth by
the sun. The heat, which becomes free on or near the surface
of the earth, w^arms the adjoining air and causes it to rise, its
place being taken by colder air from other parts of the earth.
The ascending air, after cooling, sinks again in its tuin. In
this manner a circular motion exists between the equator and
the jioies. Owing to a combination of these currents with the
motion of the earth, modified wind directions are produced.
The prevailing wind directions on the northern hemisphere
are, llicreforc, from the south-west and the north-east,
according as to whether the original current started from the
tropics or the polar region.
A second cause of wind currents, especially of storms or
gales, is the sudden condensation of considerable quantities of
aqueous vapour, which forces air to rush from all sides into
the space of reduced pressure.
Air currents arc of paramount importance to all organic
life on the earth, because they produce a thorough mixture of
SOIL, 23
the constituents of the atmosphere. Without them, the land
would soon lose all moisture. The motion of the atmosphere
ensures a proper distribution of moisture, carbon dioxide,
oxygen and nitrogen over the earth.
Air currents affect forest trees injuriously principally in two
ways : —
(a.) By unfavourably modifying the temperature and
moisture of a locality.
(b.) By injuring, breaking, bending, or overturning them.
Dry winds frequently reduce the moisture of a locality to a
dangerous degree ; moist and cold winds may reduce the
temperature, and thus interfere with the healthy growth of
the trees. Strong winds may break the leading shoots or
side branches, cause trees to assume a curved shape, or even
throw single trees and whole woods to the ground.
The damage done to trees by strong winds differs very
considerably according to species. Shallow rooted trees, like
the spruce, suffer most, while deep rooted trees, like oak or
Scotch pine, are much less affected. The most dangerous
winds in Western Europe are those which blow from south-
west, west, and north-west. Occasionally north-east winds
are also dangerous.
Section III. — Soil.
It has been already stated that plants, and more especially
trees, require a certain layer of soil, into which their roots
penetrate, and which provides them with nourishment and the
means of stability. Wherever this layer of soil is deep enough
to meet the above requirements, the subsoil is only of indirect
importance, but in the case of shallow soils the subsoil has, as
a rule, to undertake part of the ordinary functions of the soil.
Under any circumstances, the subsoil furnishes the materials
from which the mineral parts of the soil are principally
derived. Hence, in speaking of the soil, the subsoil is more
or less included.
:14- LOCALITY AND FOREST VEGETATION.
1. ()ri;iln of Soil.
All soil is origiiiiiUy the result of the disintegration of the
rocks of the earth, ^Yith the addition of certain organic sub-
stances. In some cases the soil now overlies the rock from
which it has been derived, in others it has been carried away
by violent convulsions, or the action of water and air currents,
and deposited again in other places. In the former case the
soil is called " indifie no ks,'' and in the latter " cov^u'." The
most important form of the latter is alluvial soil, formed b}'
deposits near the sea coast, in river deltas and inland by water
courses and lakes, as well as by the action of air currents.
2. Formation of Indigenous Soil.
The formation of soil is due to a variety of agencies, which
are either of a mechanical, chemical, or organic nature.
a. Mi'cJianiml At/rncics.
Amongst these, heat takes the foremost place. The heating
of rocks produces an unequal strain and pressure, which cause
them to burst in various directions. Then, if water penetrates
into the interstices and freezes, it forces the particles asunder,
thus further breaking up the rock. "Water is also a powerful
agency owing to its dissolving action.
h. Clicmiral Afjcn'irs.
Wlien oxygen and water, wliicli contains carbon dioxide
and other acids, come into contact with tlio rock, they form
chemical combinations with its elements. The oxygen acts
especially on the metals (as compounds of iron), forming, by
the addition of water, hydrates of metallic oxides. This
process, accompanied by an increase of volume, destroys the
previous cohesion of the rock. Water containing carbon
dioxide and other acids penetrates the rock, dissolves its
various constituents and carries off various substances, such
as \mo, miignc.sia and jiotash.
FORMATION OF SOIL. 25
The rate of chemical decomposition depends on the tempera-
ture ; the higher the latter, the quicker the decomposition.
Hence it is far more rapid in tropical than in cold climates.
r. Organic Afienriefi.
When mechanical and chemical action have commenced the
decomposition of the rock, organic action sets in. Lichens,
followed by mosses, appear on the surface of the rock, which
further accelerate disintegration by keeping the surface moist.
Next, the roots of these plants penetrate into the finest fissures
and assist mechanical action. In this manner a soil is
gradually formed, which consists of fragments of rock and
remnants of dead plants, suitable for the support of more
highly organised plants, such as grasses and herbs ; these are
followed by shrubs and trees, which penetrate with their roots
deeper and deeper into the rents and fissures of the rock, and
further accelerate disintegration.
When this process has gone on for a sufficient length of
time, the outer part of the earth's crust consists of a layer of
varying depth, which, commencing from below, changes
gradually from the solid rock into broken rock, or brash, then
into smaller pieces of rock, or subsoil, and ultimately into the
formed or surface soil.
At first sight it would appear, that the composition and
quality of the soil depend solely on the composition of the
original rock, out of which it has been formed. This is, on
closer investigation, found to be tlie case only to a limited
extent, because, in the first place, certain important substances,
such as potash, magnesia, lime, may be carried away and lost
during the process of disintegration ; secondly, organic sub-
stances are added ; and thirdly, the fertility of the soil depends
not only on its chemical composition, but also, and often
chiefly so, on its physical properties. All that can be said is,
that certain kinds of rock yield ordinarily a soil of a certain
description, but subject to modifications, which depend on the
peculiarities of each case. On the whole, the attempt of
26 LOCALITY AND FOREST VEGETATION.
estimating the qiialitj^of a soil l)y its geological origin only has
almost invariably failed, since tiie same rock may produce
soils of varying chemical composition and physical properties.
;}. ('i»)ip(>Hiti()ii III' Soil.
Soil consists generally of the following substances : —
(a.) Mineral matter, taken from the decomposed rock, or
carried to the area by water and air currents.
(b.) Organic matter, being remnants of plants and animals,
(c.) AVater, partly liquid, partly in the shape of vapour.
(d.) Gases, such as air, carbon dioxide and ammonia.
A. Mineral Subsf/mces in Ihc Soil.
. The mineral substances form, in the majority of cases, the
greater part of the soil ; they may be arranged into the following
four groups : —
{a.) Earths.
{},.) Salts.
(c.) Acids.
(ii/ imntJd is
formed by the action of an excessive supply of air, or rather
absence of moisture, on certain plants, such as heather.
Acid humus is the result of deeomposition, if there is an excess
of moisture and a deficiency of air in the soil. Only mild
forest humus acts altogether favourably upon forest vegetation.
C. ]Valn:
Water is the most important component part of the soil, as
plant life is impossible without a certain (piantity of moisture.
It affects vegetation principall}" in the following manner : —
{(I.) It assists in the decomposition of the rocks.
(/>.) It assists in the formation of humus, and regulates
botli the admission of air into the soil and its temperature.
(r.) It is an important agent in the process of nourishing
and shaping the plant. More; especially' it carries through
the roots the mineral substances from the soil into the
plant.
However favourably a certain degree of moisture in the soil
may act, an excess of water, especially if stagnant, is always
injurious; it reduces the activity of the soil (by driving out
air), lowers the temperature, increases danger from frost, and
is lial)le to render the soil acid.
The soil receives water from one or more of tlu^ following
sources : —
(1.) From the atmosphere, as dew, rain, snow, hail, or as
vapour condensed by the hygroscopic action of the soil.
(2.) From ground water resting in the subsoil.
PHYSICAL PROPERTIES OF SOIL. 29
(3.) From inundations, whether natural or artiliciaL
Water derived from the atmosphere acts most favourably',
provided the supply is suitably distributed over the different
seasons of the year, and the soil is capable of retaining mois-
ture sufficiently long during dry weather. Where these con-
ditions are wanting, ground water is likely to act more favour-
ably, because it produces a more even degree of moisture in
the upper layers of the soil. Natural inundation water is, in
many cases, objectionable, because it renders the soil too wet
at one time, and too dry at others. Artificial inundation, or
irrigation, produces very favourable results, but it is generally
expensive.
D. Gases.
The gases, such as air, carbon dioxide and ammonia, have
been dealt with in section I. of this chapter. It is only neces-
sary to add, that the amount of air in the soil varies within
wide limits, and that the amount of carbon dioxide depends on
the quantity of organic matter in the soil, and the rate at
which it is decomposed.
4. PJiysical Properties of Soil.
The principal physical properties of importance in sylvi-
culture are the following : —
a. C'o)isisfefic//,
or binding power, the cohesion between the different
particles of the soil. It depends on the chemical composition
of the different parts, the degree of division, and the quantity
of moisture in the soil. Generally, it is greatest in clay and
smallest in sand. An admixture of humus moderates both
extremes.
b. Sliriiikinij,
or the reduction of the volume of the soil imder the process
of drying. It causes cracks in the soil, followed by the
exposure of the roots. Heavy soils crack more than light
soils.
30 LOCALITY AND FOREST VEGETATION.
r. Ca)yiiiiii In hohl Wafer.
It is generally proportional to the percentage of tine earth
and humus in the soil.
>/. HlfijrOftropicill/,
or the capacity of the soil to attract and condense aqueous
vapour from the atmosphere. It depends on the degree of
division of the particles, and on the temperature. The liner
the division, the greater the hygroscopicity ; more vapour is
condensed at a low than at a high temperature. Soils rich in
humus show the greatest hygroscopicity, next clay, then loam,
then lime soils, and it is smallest in sand.
e. TenarHi/ in reUtinhuj Moisture
is greatest in clay soils, moderate in calcareous soils and
smallest in sand.
/. I'lrmeahilitji,
or the capacity to let water pass through, is greatest in sand,
especially if of a coarse grain, and smallest in clay. Humus
soil approaches clay, while calcareous soils and loam stand
about half-way betw^een the two extremes. Stiff clays are
liable to be altogether impermeable ; in many cases the clay of
a mixed soil is gradually carried into the subsoil, where it
forms an impermeal)le layer, frequently bound together by
oxide of iron.
(J. The Power to retain Satta dissolved in Water
depends on the proportion of line earth in the soil.
//. 'Hie ( 'aparitij to liccome Heated
is greatest in sand, and smallest in clay. Calcareous soils
approach sand ; loam approaches clay. Sand and calcareous
soils are generally hot soils, while clay is a cold soil.
/. (li)ierat.
Depth intensities the etliect of the various physical proper-
ties. A depth of 4 feet may be considered as sufficient for
almost any species, and many can do with considerably less.
CLASSIFICATION OF SOILS. 31
Where a sufficient depth of soil is not available, the direct
assistance of the subsoil is called in, especially its degree of
permeability. The depth depends chiefly upon the nature of
the rock and soil, the stratification of the rock, the situation,
and the general shape of the surface of the ground. The
nature of the I'ock governs the rate at which it is disinte-
grated, and the rock may be more or less permeable. An
impermeable subsoil is all the more injurious the nearer it is
to the surface, because it makes the surface soil too wet and
cold at one time, and too dry and hot at others, apart from
the fact that the roots may not find sufficient room for
spreading, or that the stability of trees may be endangered.
A vertical stratification and a much crumpled state of the
rock act most favourably upon the movements of water in the
soil and the penetration of the roots ; a horizontal stratification,
if unaccompanied by crumpling, is generally the least favour-
able form. Low lands have ordinarily deeper soils than high
lands. On ridges and steep slopes the soil is liable to be
washed away, while it is collected in depressions. In the
former places the covering of dead leaves is lialjle to be
blown away by wind.
All physical properties are of special importance through
their action upon moisture. In this respect the chemical
composition of the soil is of less importance than the admixture
of humus and the degree of division of the particles, whether
the latter are fine or coarse grained. It is for this reason
that sand and clay represent, ordinarily, the extremes.
6. Classi/icatioii of Soils.
For the purposes of sylviculture soils may be classified,
either according to their chemical composition, or according
to one or other of their physical properties.
a. Classififutioii according to Chemical Coui/iosi/iu/i.
It is, of course, out of the question to attempt a classifica-
tion according to all component substances, nor is it necessary,
•3-Z
LOCALITY AND FOREST VEGETATION.
because the importance of the four substances, sand, clay,
Hme and humus, outweighs that of all other substances so
much, that the latter need not be taken into account in this
place.
The subjoined table gives the composition of the ten principal
classes of soils (according to Church) : —
Percentage of :
1 NamoorSoil.
Clay.
Cal.-.ium
Carbonate.
Sand.
Organic
Matter.
1 1. Loams or Free Soil
_
20—30 5—10
50—70
2—.".
' 2. Clays
_
over 40 under 5
under 50
2 .-)
3. Clav-sands
,. 3(1
.")
50—70
2— r.
4. Marls
„ 30
.-)— 10
under 50
•2 .-.
5. Peaty Clay
., 30
under :>
„ 50
over 5
a. Sands
niidiT in
")
over 80
2-.-.
7. Calcareous Sands
.. HI
.".— 10
., 70
2—5
j 8. Peaty Sands .
.. 10
under .">
:, 70
over 5
9. Calcareous
.. 10
over 10
50-70
2—5
10. Peats
., 10
under 5
under 50
over 35
Note
.—Lime improves 2. 8, '> and 8.
Draining improves 2, 4, ") and 10.
Irrigation improves 6 and 7.
Soils of sul)ordinate importance are : —
Dolomite, a chalky loam with much magnesium carl)onate.
Gypsum, a soil which is rich in calcium sulphate.
Salt soil, which contains an excessive percentage of salts,
especially sodium chloride.
Farmginous soil, which contains an excessive proportion of
ferric oxide.
According to the preponderance of one or other of the
principal ingredients, numerous subdivisions have been made,
such as sandy, or marly clays ; loamy sand, sandy loam,
marly sand, sandy marl, etc.
Clay, loam and calcareous soil are, as a rule, minerally
strong soils, while sandy soils are less strong, liuiuus soil
may be mild, dry, or sour humus soil ; the lirst acts very
favourably upon tree growth, the two latter unfavourably.
CLASSIFICATION OF SOILS. 33
Soils may also be classified according to the rapidity with
which the humus is decomposed, as : —
Very active soils : Such as dry porous sand and calcareous
soils, in which the decomposition of humus is excessively
quick.
Active soils : Such as moderately moist loamy sand, sandy
loam and loamy marl, in which the decomposition of
humus proceeds at a rate favourable for growth, without
actually exhausting the supply of organic matter.
Moderately active soils : Such as stiff clay, wet soil, heather
soil, where the decomposition is too slow for a healthy
development of most plants.
Inactive soils : Such as peat soil, shifting sand, etc., in
which, either from excess of moisture or absence of
humus and rest, little or no decomposition takes place.
b. Classificafion accordinij to Physiral Properties.
Of the various physical properties the degrees of consistency
and of moisture are of special importance in sylviculture.
According to consistency, soils may be classified in the following
manner : —
Light soils : All soils which contain much coarse grained
sand or much humus.
Loose soils : Such as peat and moor soils, which are elastic
and swell during rainy weather ; they are also much
lifted by frost.
Binding soils : Soils of moderate cohesion, such as fine
grained loamy sands, coarser grained sandy loams,
calcareous soils, especially marl.
Heavy soils : Such as fine grained loam, clay with coarse
sand.
Stif soils : Such as clay with a limited quantity of fine
grained sand.
In classifying soils according to the degree of moisture, a
distinction must be made between the average degree of
s. D
3i LOCALITY AND FOREST VEGETATION.
moisture and the condition of the soil during the growing
season, as set forth in the following arrangement : —
JVet sail : Water flows from it without the application of
pressure. — Even in summer water runs off in drops on
the application of pressure.
Moist .sail : On pressure being applied, water falls in
drops. — During summer the soil does not become dry
beyond one inch below the surface.
Frc'sJt soil : Leaves traces of moisture on the palm of the
hand on being pressed. — During summer it does not
become dry beyond six inches below the surface.
Dnj suil : Has lost the dark colour due to the presence of
moisture, but does not fall to dust on being broken. — In
summer it becomes dry to a depth of 12 inches within
a week after a good soaking rain.
Arid soil : Falls to dust on being broken. — In summer it
dries up to a depth of more than 12 inches within a few
days after a good soaking rain.
Section' IY. — Effect of the Soil li-on Eohest
Vegetation.
In estimating the efifect wliicli differently constituted soils
have upon forest vegetation, and more especially ui)on tree
growth, the forester is guided by the demands made by the
trees upon the soil. Ordinarily the soil sliould provide the
tree with : —
(a.) Stability.
{b.) Space for a suitable spreading of the root system.
{<:.) Moisture, in suitable quantities at all times.
{(l.) Nourishing substances, in sufficient quantities and in a
condition suitable for absorption by the roots.
Any soil which meets these requirements is fertile for sylvicul-
tural purposes, and experience has shown, that fertile forest
soil must possess the following properties : —
(J.) A sufficient depth.
EFFECT OF SOIL ON FOREST VEGETATION. 35
(2.) A suitable degree of porosity.
(3.) A suitable degree of moisture.
(4.) A suitable chemical composition.
1. Siirjirieiif Depth.
The depth is measured by the thickness of the layer of
soil, and of that portion of the subsoil which can be pene-
trated by the roots. In due proportion to depth are the space
available for the root system, the store of nourishing sub-
stances, the stability of the trees, and the state of moisture
in the soil.
The root sj'stem differs considerably in the several species ;
some develop a tap root, which is maintained for a shorter or
longer period, such as oak, elm, Scotch pine, silver fir, maple,
sycamore, ash, lime, larch ; others have strong side roots,
which send down deep going rootlets, such as alder ; others
again go to a moderate depth, as beech, hornbeam, aspen and
birch ; finally some spread altogether near the surface, such
as spruce. The nature, composition and degree of moisture
of the soil modify the root system to some extent, which in
young trees frequently differs from that in older trees.
On the whole, certain species thrive well only in deep soil,
while others can subsist in shallow soil, though they prefer
the former. The best indicator of the depth of soil is the
height growth. A sufficient depth produces full height
growth ; with deficiency of depth the height growth falls oft".
Hess* classifies the trees as follows, in respect of their
demands for depth of soil : —
Species wkicli are satisfied icitli shalloic soils : Spruce,
mountain pine, birch, aspen, mountain ash.
Species ichich require moderate depth : Austrian pine, Wey-
mouth pine, beech, hornbeam, black poplar, tree willows,
alder, horse chestnut.
* Encyklopadie imd Methodologiu der Foist wisseuschaft, by Dr. Kichard
Hess, 1«8S.
D 2
36 LOCALITY AND FOREST VEGETATION.
S2)eci<'s which require fjrcater deptli : Scotch pine, Cembran
pine, elms, Norway maple, sycamore, white poplar.
Species irldclt rcindre (jreatest depth : Silver tir, larch, ash,
lime, sweet chestnut, and especially oaks.
At the same time, the roots of these species go rarely to a
:lepth of 4 feet below the surface, unless they do not find
sufficient moisture in the upper layers of the soil, a case
occurring in countries with a long dry season.
2. .1 suitable Deyree of Porosity.
Neither too firm nor too loose soils are favourable for tree
growth. Too firm soils make the penetration of the roots
difficult, if not altogether impossible, prevent the admission
of the necessary air, interfere with the movement of water,
and incline towards swampiness, accompanied by increased
danger from frost, and by strong shrinking and cracking in
summer. Too loose soils endanger the stability of the trees,
are liable to be carried away by water or wind, suffer from too
rapid drying and too rapid decomposition of the humus, and
the plants growing in it are subject to frost lifting. The best
soils are of middling consistency, such as loam and calcareous
soils with a good layer of humus.
3. A suitable Degree oj Moisture.
By a suitable degree of moisture is here understood that
degree which corresponds to the natural requirement of any
particular species, which it is desired to grow. The more
uninterruptedly that degree is maintained throughout the
growing season, the more favourable will be the development
of the tree.
Apart from climate and subsoil, the condition of the soil
itself, its depth, porosity, the nature and proportion of its
component parts, affect the degree of moisture. The forester
can d(j much, either to preserve moisUue in the soil by
EFFECT OF SOIL ON FOREST VEGETATION. 37
excluding or reducing the agencies which dissipate it, or, if
there is excess of moisture, by accelerating its consumption,
or by draining.
The absolute quantity of moisture required annually by
each species is still under investigation, but experience has
shown, that a fresh soil with, as far as practicable, an even
and constant degree of moisture suits most of the species
enumerated above. For the rest, they may be classified as
follows : —
Most Dwistiire in the soil demand .- Common alder ; next to
this ash, most poplars and willows.
Moist soil like : Cembran pine, hornbeam, elm, lime,
mountain ash, pedunculate oak.
Fresh soil like ; Silver fir, spruce, larch, beech, sessile oak,
Norway maple, sycamore, Weymouth pine sweet
chestnut.
On dry soil thrive : Corsican pine, Scotch pine, Austrian
pine, birch, acacia, aspen.
4. A suitable Chemical Co)nposition.
Apart from water and gases, the soil consists of mineral
and organic substances. These affect the development of the
trees partlj^ by providing nourishment and partly by determin-
ing the physical properties of the soil. Woody plants take by
far the greater portion of their nourishment from the air, more
especially carbon, but a certain portion, including the mineral
substances, is derived from the soil. Hence it is of importance
to ascertain the actual quantities of such substances in the
plant. The contents of mineral substances vary in different
parts of the tree ; thus wood taken from the stem generally
contains less than 1 per cent, of ashes (according to weight),
branches and twigs about 2 per cent., bark alone 2 — 3 per
cent., and leaves and needles from 4 — 6 per cent. Eber-
mayer* gives the following quantities of the more important
* Physioloeische Chemie der Pflanzen, Volume I., patre 701.
;is
LOCALITY AND FOliKST VIUJETATION ,
substiinces, wliit-li aii average (•io[> takes from the soil, per
acre and year : —
Table showing the prixcipai- Mineral Substances taken Annually
BY vAiuous Field and Forest Crops from an Acre of Land.
Dc-scriptioii of Crop.
Total
Qn.iiitity
of Ashes.
KoO. I CaO.
MbO.
P/),.
SOs.
SiO.2.
live, wheat, barley, oats
Leguminous Crops,
various
Colza ....
Clover (hay)
Potatoes
lieet ....
Meadow Hay
Tobacco
Wine ....
Averacre .
Croj)s of Trrr.s. moid ,i„(l
lea res :
Beech, hifrh forest
Silver fir
spruce ,,
Scotch pine ,.
Average .
Cnipg of TrrcK. wood onhj :
Beech, high forest ' .
Oak
Silvei' fir „
Spruce .,
Scetcli ]iine ,,
Birch, high forest
Average .
11,s.
]8(J
173
1 '.»'.)
308
281
820
294
2U
!'.)!>
23.-.
28
44
.52
98
107
164
71
84
lbs.
14
44
39
107
36
36
44
27
41
lbs.
'•*
11
14
27
18
24
18
13
1.5
lbs.
21
27
43
36'
32
28
27
16
24
lbs.
4
9
27
11
14
11
11
12
lbs.
100
9
9
9
8
14
107
7.5
78
43
17
28
11
37
194
123
138
52
126
13
16
8
6
S9
62
24
1.5
10
8
12
10
4
4
4
3
2
.56
8
4.5
6
11
62
10
8
3
29
27
24
17
20
13
12
2-7
6
4
2
2
13
18-7
4
9
8
4
3-7
0-9
3
2
1
2
2-3
0-9
1-8
1-3
0-9
1-2
0-3
0-2
0-9
0-6
0-2
0-1
2-7 '
0-4
v\
0-4
0-9
19
4
9
2
1-4
0-4
1-6
The (lata of this table justify the following conclusions: —
(1.) The substances required by foresttrees are, (i[ualitativel^y,
tlie same as those required by field crops.
(2.) Beech high forest requires for the production of leaves
and wood nearly as much mineral substances as an average
field crop ; it requires more lime, but much less of the rarer
substances, such as potash and phosphoric acid.
(3.) Conifers require smaller quantities, especially Scotch
EFFECT OF SOIL ON FOREST VEGETATION. 89
pine, which is satisfied \Yith about one-fourth of those wanted
by beech.
(4.) For the production of wood alone (excUuhng the leaves)
forest trees require much smaller quantities, than field crops.
Thus beech takes only one-ninth, Scotch pine about jV^h, and
the six species enumerated on an average about J^th of the
quantity required by field crops. Of the rarer substances,
potash and phosphoric acid, trees take, on an average, only
about ij\y^h of the quantity necessary for field crops.
(5.) Almost any soil can furnish a sufiicient quantity of
mineral substances for the production of a crop of trees,
provided the leaf mould (humus) is not removed, and good
soils will continue to do so, even if a certain portion of the
humus is taken away. If, however, the removal of litter is
carried on annually and for a long period, any but really
fertile soils are likely to become exhausted, just as lands, on
which fields crops are grown, cannot as a rule go on for ever
without manuring.
(6.) Poor soils, which are not capable of producing a crop
of broad leaved trees, may yet be able to yield a fair return if
planted with less exacting conifers, especially Scotch pine.
The above conclusions agree with the results of practical
experience. It has been found, that tbe quantity of wood
production is not directly proportionate to the quantity of
mineral nourishing substances in the soil. Again, woods
thrive equally well on soils of the most different geological
origin, while great differences exist in the development of one
and the same species if grown on soils of the same geological
origin. These phenomena are explained by the great im^Dort-
ance of the physical properties of the soil, depth, porosity and
a proper degree of moisture. To ensure a favourable condition
of the physical properties should, therefore, be the forester's
chief aim, and this he can do best by preserving the humus,
especially on middling and poor soils. Humus increases the
depth of the soil, absorbs from the atmosphere considerable
quantities of aqueous vapour, carbon dioxide and ammonia ;
40 LOCALITY AND FOHEST VKOETATION.
it is capal)k' of holding ti large (juantity of water, which
it gradually gives up to the lower layers of the soil ; it
loosens too firm a soil, and gives somewhat more consistency
to a soil which hy itself is too porous ; finally it moderates
the extremes of cold and heat. The poorer a soil the more
important is the preservation of tlie humus, provided it is
not acid.
5. Summarji.
Summarising all the demands which forest trees make on
the soil, it may he said that all species like a soil M-hich is
minerally rich, deep, porous, fresh, warm and rich in humus,
such as a mild loam with a good layer of humus. Some
species find the necessary conditions more on one class of soil
than on another ; for instance, oak, beech, ash, elm, maple,
and Austrian pine, like a certain quantity of lime in the soil,
probably less on account of its chemical composition than of
the physical qualities which an admixture of lime produces.
]\rost coniferous trees, on the other hand, are more frequently
found on loamy and sandy soils.
Though all trees like a good fertile soil, the several species
differ considerably as to the minimum of fertility on which
they can thrive ; that is to say, some are more exacting in
their demands than others. In this respect the following
scale is suggested : —
Least €.ractiii;i air .- Austrian pine, Scotch pine, Weymouth
pine, birch, poplars, tree willows, mountain ash, acacia,
mountain pine, white alder.
Moderately exactimi are : Spruce, Cembran pine, larch,
common alder, lime, osiers, horse chestnut, hazel,
hornbeam, Norway maple, Douglas fir.
Most cxactinfi are : Silver lir, beech, sweet chestnut, sessile
oak, sycamore, ash, elm, and pedunculate oak.
It will be observed that the valuable broad-leaved species
are, on the whole, more exacting than the soft broad-leaved
species and the conifers.
P^FFECT OF FOKEST VEGETATION ON THE LOCALITY. 41
Any classification like that given above must, however, be
received with some caution ; its object is merely to give a
general idea of the subject. In practice deviations occur
constantly, according to the local conditions under which the
trees grow.
Section V. — Effect of Forest Vegetation on the
Locality.
It has been shown in the previous sections that the
condition of the locality governs the growth of forest trees.
It is now necessary to consider the effect of forest vegetation
on the locality, more especially on two of its factors —
humus and moisture. This effect is chiefly produced by the
following two agencies : —
(1.) The protection which growing woods afford to the soil
and adjoining layers of air.
(2.) The humus which is formed by the fall of the leaves,
branches, twigs, flowers, fruits, etc., and by certain
plants growing under the shelter of the trees.
In well stocked, or crowded, woods the crowns of the trees
form a thick leaf canopy, or complete cover overhead. If
the trees are all of the same age and height, the leaf canopy
is at a uniform height above the ground, that height being
at first small, but increasing with age. In woods of uneven
age the cover is of a somewhat different nature ; it consists
of groups of crowns at varying distances from the ground.
In either case the cover overhead protects the soil and
adjoining layers of air against sun and wind ; in even aged
woods more against sun, and in uneven aged woods more
against wind.
Again, the trees shed their leaves, flowers, fruits, and even
branchlets, while mosses and other plants, which thrive
under the shelter of the leaf canopy, die ; thus a layer of
humus on the soil is formed. Finally the roots of the trees
penetrate into the soil and keep it together.
42 LOCALITY AND FORKST VKOETATION.
The shelter from al)ove, tlic linmns on the soil, and the
roots of the trees together prodiu'e certain efTects, wliich may
be summarised as follows :—
(1.) The temperature of tlic soil and the adjoinhi^ air is
lowered during the day and laised during the night ;
hence the extremes of temperature are moderated,
and the climate rendered more equable.
(2.) The mean temperature of the soil and the adjoining
air is lowered. The reduction is greatest in summer,
next in spring, next in autumn, and it is slight in
winter ; it is also greater in the soil than in the
adjoining air.
(8.) The relative humidity of the air is increased, the eva-
poration from the upper layer of the soil reduced, and
precipitation may be increased.
(4.) A favourable degree of moisture in the upper layer of
the soil is maintained.*
(5.) Noxious forest weeds are kept in check.
(6.) A steady and suitable progress in tlie decomposition
of the humus is ensured, whereby the physical
qualities of the soil are improved, or at any rate
maintained.
(7.) An additional supply of organic and nitrogenous
matter taken by the plants from the atmosphere and
brought into the soil by the falling leaves, flowers,
fruits, and twigs, decaying mosses and other plants,
is procured.
(8.) The soil is protected against the mechanical action of
water and air currents.
In order to produce these effects in a high degree, it is
necessary that the leaf canop}' should be dense, so that it
not only keeps out sun and air currents, but also yields a
heavy fall of leaves for the production of humus. Only
* Iicceiit invest if^iit ions niiulc in Russia and in France seem to indicate, tliat
llio level of the i:roiind water in the sod is Inwcied by a itoj) of forest veirctation
in luc;ilitic< witli a small or inodei-ate rainfall.
EFFECT OF FOREST VEGETATION ON THE LOCALITY. 43
certain species of forest trees possess these two qualifications.
During youth most species answer, no doubt, very well ;
with advancing age, however, the crowns are not only lifted
higher and higher from the ground, but most species thin
out considerably. The result is, that the leaf canopy be-
comes more and more interrupted and thinner, followed by a
crop of noxious weeds, or too rapid decomposition of the
humus, accelerated evaporation of the moisture from the
upper layer of the soil, and generally a reduction of the
fertility of the soil. To prevent such results, the forester
must either cut over the woods before the process of thinning-
out has proceeded too far, or underplant such woods, or
cultivate species which are capable of maintaining a complete
cover overhead up to an advanced age.
Amongst the timber trees with which this l)Ook deals,
beech, silver fir, spruce, and hornbeam, are the species
which, above all others, preserve a complete leaf canopy
until, or nearly to, maturity. These are shade bearing
species. All other species are, with certain modifications,
less capable of preserving the factors of the locality ; the
greater their light requirement and the thinner their crowns,
the smaller is their capacity in this respect. Those least
suitable are birch, poplars and acacia ; next willows, larch,
most pines (with advancing age), oak, ash, elm, Norway
maple, sycamore, and alder.
The production of humus from fallen leaves is greater in
woods consisting of broad-leaved species than in coniferous
woods, because the more important broad-leaved species are
deciduous and shed the whole of their foliage every year,
while, with the exception of larch, the conifers are evergreen.
The silver fir sheds about one-ninth of its foliage annually,
spruce about one-seventh, the pines about one-third to one-
fourth. The production of humus from fallen leaves is,
generally speaking, greatest when the rate of height growth
culminates.
The accumulation of humus depends greatly on the
44 LOCALITY ANI> FOREST VEGF/FATION.
rapidity with whicli the leaves are decomposed, a process
which is regulated hj the species, degree of cover overhead,
and the cliaracter of the locality. Generally speaking,
needles decompose more slowly than leaves. Of needles,
those of the larch decompose most quickly, next perhaps
those of Weymouth pine, Scotch pine, and Austrian pine,
last those of silver fir and spruce. Of leaves, those of ash,
alder, hornbeam, lime, and hazel decompose quickly ; more
slowly the leaves of oak, birch, and sweet chestnut. The
leaves of beech stand perhaps half-way, but as beech woods
enjoy a dense shade, their accumulation of humus is much
greater than that found in oak or birch woods. On cal-
careous and sandy soils, humus decomposes more quickly
than on loam and clay soils. It is also more rapid in warm
low lands than in cloudy mountain regions. The most
suitable, or normal, time for the process may be put at two
to three years, when the most favourable results in respect of
quantity and quality of humus are produced,
A few words about each of the more important species
will not be out of place here : —
Beech improves the soil in the highest degree, because it
has a dense crown and yields a heavy crop of leaves, which
decay slowly. Beech woods, if undisturbed, show a thiclcer
layer of humus than woods of any other species.
TlnniJicam approaches beech in this respect, though it
does not equal it.
Lime gives good shade and a heavy crop of leaves, but its
timber is of such inferior quality that it is rarely planted
for economic purposes.
Street eheainnt sheds a heavy crop of leaves, but the leaf
canopy is comparatively incomplete, admitting too much sun.
Oah, ash and iciUoir have too thin a leaf canopy to do
justice, generally speaking, to the locality.
Silver fir and spruce are capable of preserving a dense
cover overhead up to an advanced age.
Erert/reen conifers, other than silver la- and spruce, though
ASSESSMENT OF THE LOCALITY. 45
they may not possess a dense leaf canopy, are often capable
of preserving the fertility of the soil for a certain period,
because under their half shade mosses grow, which protect
the soil just as well as a thick layer of leaves. When the
conifers begin to thin out to some extent, the mosses dis-
appear gradually, except in very moist localities ; hence these
species should' not by themselves be treated under a high
rotation, except in very fertile soils. Of the conifers which
are here referred to, Weymouth pine, Austrian pine, Cembran
pine, and mountain pine have a fairly dense leaf canopy,
and yield a considerable crop of needles, more especially
Weymouth pine. Scotch pine has a thinner crown, and a
tendency to open out after the age of thirty or forty years,
when the moss is liable to disappear and to be replaced
by a crop of grass or heather. At the same time, the
density of the leaf canopy of this tree differs very consider-
ably according to the conditions under which it is grown.
The Scotch pine grown in the moist climate of the British
Isles gives a much denser cover, than when grown in dry
continental climates.
Larch provides but a thin leaf canopy in summer, and is
leafless in winter. It begins to thin out at an early age ;
the moss disappears quickl}', is replaced by grass, and the
needles decay rapidly, so that the tree is unfit for preserving
the fertility of the soil.
The power of preserving the factors of the locality which
is peculiar to the several species, governs their adaptability
to be raised in pure woods, a subject which will be dealt
with further on.
Section VI. — Assessment of the Quality of the
Locality.
It is the duty of the forester to determine, in the case of
any particular locality, which species is best adapted for
H) LOCAMTV AND FoUKST VK(;KTATI()N.
cultivation, so as to realise the objects of the proprietor. In
order to attend to this duty successfully, means must be
provided by which the niiaJitu, or ii'n'hl ((ijxKit;/, of the
locality can be I'eadily ascertained. Various methods have
been i)roposed for this purpose, of which the following two
will be shortly considered here : —
(1.) Assessment according to the severnf fiictors of the
locality.
(2.) Assessment according to a crop of trees already
produced on or near the locality.
"Whenever the second method is possible, it should be
followed ; only in the absence of a forest crop should the
Urst method be adopted.
A third method may be mentioned. It has been pro-
posed to assess the quality of the locality according to the
natural appearance of certain plants, which would depend
either on the presence in the soil of certain substances, or
on certain other conditions of the soil. Though this holds
good to some extent, the method of assessment by itself is
without practical value in sylviculture, but it may be used
as an auxiliary of the method now to l)e described.
1. AsS('tis)H('nt of' the Localiti/ acconliini to its scrinil Factors.
The factors of the locality naturally arrange themselves
into two groups, those of the climate and those of the soil
and subsoil.
As regards climate, it is necessary to ascertain :
(a.) The geograpliical position of the locality, that is to
say, the latitude, and in some cases, the longitude.
(/>.) The local peculiarities of the locality, such as altitude,
aspect, slope, surroundings, temperature, moisture
in the air, rainfall, (exposure to strong, cold or dry
winds, susceptil)ilily to late or early frosts, etc.
All these matters have been dealt with in a previous
section.
ASSESSMENT OF THE LOCALITY. 47
Turning to the soil, the following points, as already
indicated, require attention : —
(«.) The depth of the soil.
(/>.) The degree of porosity.
(e.) The -degree of moisture peculiar to the soil.
{(1.) The chemical composition.
A detailed examination of the factors of the soil is a com-
pHcated and difficult operation, which it is not intended to
describe here. There is, however, a somewhat rough and
ready method, which generally suffices for sylvicultural
purposes, and which will be shortly indicated.
The most convenient way of examining the soil is to dig
a hole, if possible in a spot which promises to yield average
results. On fairly level ground the spot should be selected
on an average part of the area, that is to say, neither in any
small depression nor on any slight elevation which may exist.
In hilly or mountainous localities, separate holes must be
dug on the ridge, the slope and at the bottom of the valley.
The depth of the hole must be at least equal to the depth to
which the roots ordinarily penetrate, that is to say, 8 to 4
feet. Where rock is met at a smaller depth than this, its
stratification and general composition should be ascertained,
as well as its effect upon the regulation of moisture and
the stability of the trees. One side of the hole, at any
rate, should be perpendicular, so that the thickness of the
successive layers of the soil can be measured, in so far as
they are indicated by different colour, different degree of
cohesion, and other outward signs. The depth to which
the soil is coloured dark by humus should be specially
noted.
This operation will show, whether the soil is sufficiently
deep to admit of a proper spreading of the roots, and if not,
the examination of the subsoil will indicate, how far the
latter can make up for the shallowness of the surface soil.
The same operation will indicate, what effect the depth and
nature of the soil have on the degree of moisture. Next
•J8 LOCALITY AND FOHKST VLffKTATlON.
the degree of division, or the nature of the grain of the soil,
must be ascertained. This can be done by shaking a sam-
ple, if necessary of each successive layer, with about three
times its volume of water in a graduated tube, until all parts
are thoroughly separated ; the tube is then placed in a
vertical position and watched. As coarse grains settle more
quickly than fine grains, it follows that the time occupied
compared with the thickness of the deposit indicates the
degree of division of the particles. A high degree of division
indicates a stiff soil, the presence of coarse grains the
reverse, and thus an idea can be formed of the degree of
porosity.
If necessary, the capacity to absorb water, to attract it
from the subsoil, to retain it, and the hygroscopicity of the
soil can be ascertained by special experiments, l)ut in practical
sylviculture they are rarely called for.
The exact composition of the soil can only be ascertained
by means of a chemical analysis. In practice the forester
can easily acquire the faculty of distinguishing in a rough
and ready manner between the several constituents. He
recognises: — Clay by a high degree of cohesion, a fatty
feeling, active absorption of water while emitting a clayey
smell, slow disintegration in water, slow drying followed by
cracking, frequently a grey colour, etc. ; loam by a lesser
degree of cohesion than in the case of clay, rougher feeling,
quicker disintegration in water, and generally a more reddish
colour ; Utuc by active effervescence if treated with an acid,
porosity, light whitish to greyish-white colour, which is, how-
ever, frequently turned red by iron, a rough but line grained
feeling, etc. ; sand by very slight cohesion, grinding between
the teeth, or hard grainy feeling, immediate disintegration
in water and rapid settling down in it, a light, glossy, shiny,
yellowish-white colour, often converted into red by iron, into
white by lime, into black by humus ; humns by its porosity
and light weight, peculiar smell like that of fresh garden
earth, rapid disintegration in water, wliicb remains dark
ASSESSMENT OF THE LOCALITY. 49
coloured for a long time, blackish colour which disappears on
roasting ; iron by red colouring, etc.
In order to recognise more easily the principal constituents
of a soil and their proportion, a sample may be mixed in a
glass tube with about twice its volume of water, well stirred
until completely dissolved, and then allowed to settle. At
the bottom of the glass tube the following deposits will be
observed, beginning with the low^est : —
First : The rougher grains of sand.
Second : The finer grains of sand.
Third: Lime, chalk and the coarser clay.
Fourtli : The finer clay and particles of humus.
The thickness of the layers indicates the proportion of each
substance.
In spite of the most persevering attempts, experience has
shown that the assessment of the locality in the manner
indicated above is always subject to grave errors, because the
various factors may compensate each other, replace one
another, or may be altogether unassessable. To make
matters worse, the factors are rarely the same over exten-
sive areas, but change from one spot to another. On the
whole, the method which has just been indicated can only
serve as a make- shift when no better means of assessment
are available, or as a help in the application of the method
now to be described.
2. Assessment oj the Loecdity according to a Crop of Trees
prodiiccd hy it.
When a locality has already produced a crop of- trees, it
may be assumed that, unless extraordinary events or irregu-
lar treatment have interfered with the development of the
trees, the effects of all its factors have found due expression
in such crop, which is therefore the best guide for the as-
sessment of the quality, or yield capacity, of the locality.
If, for instance, an acre of ground has produced a total
s. t;
50 LOCALITY AND FOREST VEGETATION.
quantity of 5,000 cubic feet of wood in the course of 100
years, the quality, or annual yield capacity, is represented by
^*^^^=oO cubic feet, in other words, by the mean annual
production.
The applicability of this method depends principally on
the following three conditions: —
(a.) That the existing wood has grown up under normal
conditions ; in other words, that no extraordinary dis-
turbing events have occurred which affected the health
and development of the crop, as, for instance, damage
by cattle or deer, insects, fire, theft, removal of litter,
faulty treatment, etc.
(h.) That the factors of the locality have not undergone
any decided change, either for the better or worse,
during the production of the crop ; for instance, the
stock of humus or the degree of moisture may have
been affected by external interference.
{('.) That the existing crop is of a sufficient age to make
sure that the factors of the locality have found a
thorough expression in the same, since a wood may
thrive well up to a certain age and then fall oft' con-
siderably.
Whenever these conditions exist to a fair extent, the
method of assessment is the best which is at the forester's
disposal ; and in its application he need not restrict him-
self to a crop actually growing on the area, but may be
guided by one growing on a neighbouring piece of land,
provided the general conditions are about the same in both
cases.
A great quantity of data bearing on the j'ield capacity of
land under forest has, in the course of time, been collected
and brought together in so-called " Yield Tables,'' that is to
say, tables which indicate the yield which an acre of land
may reasonably be expected to give according to whether it
belongs to one or the other quality.
The details regarding yield tables will be found in
ASSESSMENT OF THE LOCALITY.
51
Volume III. of this Manual,
following data may be given
By ^Yay of illustration the
Total Production of Timber and Firewood in the course of One
Hundred Years, in solid Cubic Feet per Acre.
Species of Tree.
Total
Production on the
I.,oi-Be.st
Quality.
II., or
Medium
III. , or
Lowest
Quality.
Quality.
Silver fir . . .
23,900
16,500
10,700
Spruce ....
22,200
1-t.OOO
7,200
) Datad erived
r.eech ....
L->,200
9,300
4,700
; from numerous
Scotch pine .
13,500
8,500
3.500
and reliable
Oak grown on alluvial
measurements.
soil ....
12,700
9,400
6,200
Larch ....
12.100
6.800
l,S0O
) Data somewhat
Alder ....
!M00
5,400
1,700
[ less
J reliable.
Birch ....
7,900
4,300
1,100
The quantities given for the first quality are the highest
which can be produced, and they are comparable for the
several species ; the same may fairly be said regarding the
figures given for the second, or medium, quality. The quan-
tities given for the third, or lowest, quality are less com-
parable, because the lowest limit suitable for the several
species differs considerably. Of our more common forest
trees, silver fir produces the greatest quantities, and spruce
comes near it. As regards oak it should be noted, that the
figures refer to woods grown on alluvial soil only ; there are
as yet no data available for oak grown on other lands.
Taking Scotch pine as an example, it may be said, that,
if a localit}^ stocked with it has produced 13,500 cubic feet of
woody matter in the course of 100 j^ears, that locality is of
the first, or best, quality or yield capacity ; if it has produced
8,500 cubic feet, it is of a medium quality ; and if the pro-
duction amounts to only 3,500 cubic feet, the quality is of
the lowest, on which that species is ordinarily grown.
The quantities given above include all thinnings taken out
of the woods in the course of the 100 years.
E 2
52
CHAPTER IT.
DEVELOPMENT OF FOREST TREES,
In dealing with the shape and development of forest trees,
it is assumed that the student has already acquired a botanical
knowledge of the several species, so that here only their sylvi-
cultural characteristics need be described, more especially
the shape peculiar to each species, the height, diameter and
volume growth, lease of life, and reproductive power.
1. Shape.
Different species of trees naturally develop different shapes.
Some species, like spruce, silver fir and larch, have a decided
tendency to form a strong stem in preference to the develop-
ment of the crown. Others, like oak, lime and sweet chestnut,
develop their crown in preference to the stem. Some species
are frequently forked, as ash, false acacia, and also elm.
Cembran pine often shows a candelabra-like shape, especially
in stony localities. The actual shape depends, however, on a
variety of influences, amongst which the following may be
mentioned : —
a. GroiriiKj Sp(i
/
A
Y^
r/
/
y\
f
A
(A
/
(y^
y
/
/
■y^:^
^
^
■M
Silvor Fir.
Spruce.
10
L'O
40 '.0 00 70 SO '.10 1110 110 I'JO
AGE, I\ YEARS.
Fig-. 2.— Diap-am illustrating the Diameter Growth of Silver Fir, Spruce, Beech,
and Scotch Pine, on Localities of the First Quality.
increment, a free position increases it ; hence height growth
and diameter growth demand frequently opposite con-
ditions. It is the business of the forester to give the most
profitable growing space ; in other words, to give to the
individual trees from time to time sufficient room to en-
courage diameter growth, without endangering the progress
of the height growth.
The effects of a great surface of foliage and unimpeded
enjoyment of light are very remarkable, when licallhy trees,
VOLUME GROWTH. 59
which have been raised in a crowded wood, are gradually
given more growing space. Such an opening out can,
provided the period of height growth has not come to an end,
produce a revival of the diameter increment, after its
maximum has been passed, due to an increased leaf surface,
or to a greater intensity of action, even if the leaf canopy
is not materially extended. This revival of diameter growth
generally lasts for a number of years, differing according
to species and quality of locality, when it gradually dies away
again. Nor does a tree profit by an excessively large leaf-
surface, because there is a limit, beyond which a tree cannot
assimilate and convert into wood the nourishing elements
available to it.
Where both great height and diameter growth are wanted,
it is best to keep the wood crowded during youth, and to give
only a moderate growing space to each tree until towards the
end of the principal height growth, when the growing space
of each remaining tree should be gradually increased, so
as to develop more extended crowns and greater diameter
growth. This is only possible while height growth is still
going on ; once that has stopped, the thinning out will not be
followed by any appreciable extension of the crowns, which
can only be produced by transferring to it the energy of
height growth. The possibility of such a transfer is longest
preserved in silver fir, spruce, oak, and beech.
4. Volume Growth.
The increase in volume depends on both height and
diameter growth, and that method of treatment which
promotes each in due propoi'tion, must ultimately yield the
largest volume ; in other words, woods should be neither too
crowded, nor too open. In the one case thin tall trees, and in
the other short thick trees would be produced. The most
favourable density of the crop can only be ascertained by
accurate statistics. General experience has shown that the
greatest volume is ultimately obtained, if the woods are
60
DEVELOPMENT OF FOREST TREES.
moderately heavily thinned from their youth onward, hut this
interferes often seriously with the ([uality of the timber.
Ajiart from these general considerations, a great difference
exists in the vohime produced by the several species when
grown in regular woods ; in this respect some of the more
important kinds may, according to the latest investigation, be
l-'ir.
•J4,000
1 —
/
•J-J,000
/
/
y~ -'0,000
{^
y
"A
/
^ ir.ooo
//
f
>2
/
1
y
^ ]-.',0pruce.
Silver Fir.
Uif.-h and
Scotch Pine.
iO CO 70 80
AGE, IN' YEARS.
100 110 120
Fig. 4.— Diagram illustrating the Numher of Trees per Acre at Various Ages, and on
"" Localities of the First Quality, of Spruce, Silver Fir, Beech, and Scotch Pine.
by itself govern the increment produced per acre, because
the latter is represented by the increment per tree multiplied
by the number of trees per acre. For instance, if an acre of
ground can hold 100 mature silver firs, each of which has a
volume of 100 cubic feet, the total volume per acre will be
62 DEVELOPMENT OF FOREST TREES.
10,000 cubic feet ; if an acre can hold 50 mature oak trees,
each \vith a vohime of 150 cuhic feet, the total volume per
acre will be only 7,500 cubic feet, or 2,500 cubic feet less
than in the case of silver lir.
The number of trees which find room on an acre of ground
depends chiefly on
(a.) The light requirement of the species.
{h.) The tendency of the species to develop the crown in
preference to the stem.
(r.) The quality of the locality.
Hence, an acre stocked w4th the light demanding birch,
ash, or spreading oak, contains a smaller number of trees and
a smaller volume than an acre stocked with beech. Again,
larch, and Scotch pine woods contain fewer trees and a
smaller volume per acre than silver fir and spruce woods.
The number of trees per acre on a fertile soil is consideral)ly
smaller than on an inferior soil.
Full details on this question will be found in Volume III. of
this Manual. In the meantime the accompanying diagram
(p. 61) will give a general idea of the number of trees found on
localities of the first quality in the case of spruce, silver fir,
beech, and Scotch pine.
5. Iniration <>/ Li/r.
A great dift'erence exists in the age which the various
species attain ultimately. If grown under conditions which
are in harmony with their requirements, the yew lives for
more than 1,000 years, the oak comes often near that age, if
it does not exceed it ; lime, elm and sweet chestnut reach and
surpass an age of 500 years; beech reaches a similar age
under favourable circumstances, but ordinarily both beech
and silver fir die before that age. A limit of 300 years may
be assigned, to ash, maple, sycamore, spruce, larch, Scotch
pine and hornbeam ; while aspen, birch, alder and willow-
live, under ordinary conditions, little beyond 100 years.
In forestry the trees are, as a rule, cut over Iwig before
DURATION OF LIFE. 63
they have reached the natural lioiit of their life. Never-
theless many cases occur, ^Yhere trees have been grown under
conditions which are not quite in harmony with their
requirements, so that they die, or at any rate fall off in
health and growth long before they would, in the ordinary
course, be cut over ; hence it is of importance to consider the
conditions under w'hich the growth continues to be healthy to
an advanced age.
In the first place, the nourishing organs, crown and roots,
must be able to develop normally in accordance with the
requirements of the tree at the different periods of life ;
in other words, they must be given at all times the
required growing space, without, however, checking their
height growth or interrupting the cover overhead for
a lengthy period of time. Unless a tree is provided with
a sufficient quantity of organs, it will not be able to
overcome successfully internal and external damage which
endangers its life. The power of resistance in this respect
differs considerably in the various species. It is great in
oak, hornbeam, lime, willow, elm, yew, and Cembran pine,
but small in alder, Norway maple, sycamore, beech, spruce.
The second condition of longevity is, that the locality
should offer to the tree all it requires for a proper deve-
lopment. On the whole it may be assumed that, where a
tree is indigenous, it finds all it requires (though this is not
without exceptions). Localities wdth different factors are
liable to be unsuited to the species, either from offering too
little or too much in respect of temperature and moisture, or
insufficient nutriment and depth in the soil, etc. Either case
may be injurious to the development of the tree, and
especially to the quality of the timber produced. For in-
stance, spruce is naturally fond of a cool climate ; by trans-
ferring it to the dry and warm air of the low lands, it
generally grows much more quickly, but does not jdeld
the same quality of timber, is shorter lived, and subject to
more dangers, than in its mountain home.
64 DEVELOPMENT OF FOREST TREES.
Trees raised in fully stocked compact woods do not live as
long as when <,m(j\v]i in the open. Moreover, in that case
various other important considerations must he taken into
account. After having weighed these, the forester decides on
the age limit which is most likelj' to realise the objects of
management.
What the objects of management are, has been indicated in
the Introduction to this volume. They govern the deter-
mination of the rotation, or the time which elapses between
the formation and final cutting over of a wood. Whatever
motives may influence the determination of the rotation from
a sylvicultural point of view, it should be so fixed under the
method of natural regeneration as to admit of a proper
regeneration of the wood, whether by seed or coppice shoots ;
in other words, the wood must l^e cut over while the repro-
ductive power of the species is in an active condition. For
further details regarding the determination of the rotation
the reader is referred to Volume III.
0. llcproductin' Poircr.
The tendency to reproduce the species manifests itself
throughout nature ; in fact the energy devoted to reproduc-
tion is frequently stronger than that bestowed upon the
preservation of life. Forest trees, in obedience to this law,
produce seed during a considerable part of their life, and in
large quantities.
In sylviculture, the reproduction of trees and woods is
effected in two distinct ways, namely : —
{(I.) From seed.
{}).) From shoots which spring from the stool or the roots,
followed, in many cases, by the division of the mother
plant.
a. Iivpr/" 30 — 40 yeitis: Scotch pine, Austrian pine,
Weymouth pine, larch, Norway maple, common alder,
lime, horse chestnut.
.4^ tJte aijc of 40 — 50 ijcarn : Hornbeam, elm, ash,
sycamore.
At the age n)(hicti<)ii in inaiiitniiii'd hci/oiiil an acjc of 40 i/fars
in the cfoif of: Oak, sweet chestnut, hornbeam, elm,
alder.
It ccasrs at an rarliey afjc in : ]jeech, birch, Norway maple,
sycamore, ash.
The conifers have no power of reproduction of this class
worth mentioning. Larch shows best amongst conifers, and
the three needled pines next.
Some species produce only stool shoots, others only root
suckers, and others again both : —
Principalbj stool shoots : Oak, hazel, hornbeam, beech, elm,
sweet chestnut, hme, black poplar, alder, ash, sycamore,
maple, willow, birch.
Princijyalhj root sachcrs : Aspen, white alder, false acacia,
white poplar, and willows.
The age to which stools live differs considerably, according
to species and locality. "While the stools of oak and hornbeam
last for centuries, those of beech are comparatively short lived.
The osiers in the Thames valley, if coppiced annually, are
said to last only about 10 years.
69
CHAPTER III.
CHARACTER AND COMPOSITION OF WOODS.
In sylviculture trees are only in exceptional cases reared in
free positions ; as a general rule they are grown in consider-
able masses, which' form more or less crowded woods. Such
woods may be composed of one species only, or they may
contain a mixture of two or more species ; in the former case
they are called j^ure woods, and in the latter mixed icoods.
Naturally pure woods occur only under certain conditions, as,
for instance, when the factors of the locality suit only one
particular species, or when the vitality and energy of one
species has gradually ousted all others. Species which appear
naturally in pure woods are called gregarious. The bulk of
the pure woods, which exist at present in Europe, are the
result of artificial interference. By far the greater number
of natural woods are mixed.
Section I. — Puke Woods.
Practically, woods are rarely quite pure, because in most
cases specimens of other species, which it was not intended to
rear, make their appearance uninvited. As long as such an
admixture is slight, accidental and not taken into account by
the management, the character of the pure wood may be said
to be preserved.
The principal advantage of pure over mixed woods is, that
they are easier to manage, because the requirements of only
one species have to be considered. On the other hand, they
have often disadvantages as compared with mixed woods,
which will be dealt with in section II.
70 CHARACTKH AND COMPOSITION OF WOODS.
The litness of a s[)ecies to l)t' laisfd in piiie woods depeiuls
on its capacity to preserve, or even improve, the factors of
the locality, in other words, whether the species preserves a
complete leaf canopy to an advanced age, and secures the
accumulation of a sutticient layer of humus. As indicated
in section IV. of chapter I., beech, silver tir and spruce act
most beneficially in this respect, and next to these some of
the pines. Apart from them, several others are frequently
grown in pure woods, such as oak. larch, Scotch pine, birch,
and willows, on account of their great utility.
Of the remaining, or so-called dcpnuh itt species, few are
found in pure woods, and then only under special circum-
stances ; for instance, hornbeam replaces beech in frost
localities, Cembran pine and mountain pine occur at high
elevations, maritime pine on dunes near the seashore, alder
in wet localities, sweet chestnut as coppice for pit wood, vine
stakes, etc. On the whole it may be said, that dependent
species may be grown as pure Avoods in the following
cases : —
(l.^i If the factors of the locality are such that an imperfect
cover and want of humus do not materially injure them ; as
in deep fertile soils, which enjoy an ample and well distri-
buted rainfall, or which are kept moist by ground water or
irrigation.
(2.) If the woods are treated under a short rotation, so that
they are cut over before any excessive interruption of the leaf
canopy has set in ; or if it is intended to underplant them,
when the}' connnence to open out, as in the case of oak, larch,
and Scotch i)ine.
(8.) If the object is to utilise localities which are only lit for
certain species ; for instance, alder and willow on wet soils,
hornbeam in frost localities, etc.
(4.) If only one species linds a ready market, or is reciuired
for a ^|icciiil [)iM'[)ose.
I'i.xcept in such cases, all ilej)eiuU:iil species should he I'aised
in mixed woods.
ADVANTAGEH OF MIXED WOODS. 71
Section II. — Mixed Woods.
A mixed wood may be so arranged that every tree of one
species alternates with a tree of another species, in which
case the mixture is called one hy single trees. Or a group of
trees of one species may alternate with a group of trees of
another species, called a mixture hy groups ; in the latter case
the groups must not be of such extent, that each acquires the
character of a pure wood.- Mixtures may also be arranged in
alternate lines or strips.
Mixed woods may be : —
(a.) Permanent or temporary.
(b.) Even aged or uneven aged.
Temporary mixtures are ordinarily called for in the following
cases : —
(1.) When the intention is to obtain an early return, by the
removal of one of the species, which should in that case be of
rapid growth.
(2.) When a tender species has to be protected (nursed)
during early youth against frost or drought, as beech and
silver fir, and to a less degree oak. In this case a hardy and
fast growing species, such as Scotch pine, larch, birch, is
raised either simultaneously or beforehand, and removed
when the tender species requires no further protection. Near
the sea coast, it is generally necessary to grow first very
hardy trees, so as to establish sufficient shelter ; more
valuable trees may afterwards be introduced between the
nurses.
(3.) When both the above objects are combined.
Permanent mixtures are established, because they are con-
sidered to have advantages over pure woods.
1. Advantages of Mixed Woods,
(a.) Mixed woods admit of a more complete utilisation of the
factors of the locality, and consequently they produce a larger
quantity of wood, if the mixture is suitably arranged. Each
72 CHARACTER AND COMPOSITION OF WOODS.
spot can l)e stocked witli tlie species which is best iulapted
to the factors of the locaUty ; lience iiici"eased production
follows.
{!).) Unless very extensive areas are availal>le, only mixed
woods enable the forester to meet the various demands of the
market. In the case of pure woods, and if a regular annual
yield of each of several species is expected, a complete series
of age gradations is required for each species, which, in the
case of a limited area, would lead" to small annual coupes.
For instance, if the intention is to grow five species on an
area of 500 acres under a rotation of 100 years, each cutting
w^ould extend, in the case of pure woods, over one acre, while
in the case of a mixed wood, the annual cutting may be live
acres in one block.
It has already been stated, that only a few species are lit to
be grown in pure woods. At the same time many of the other
species yield a very superior quality of timber, or valuable
minor produce. All these would more or less disappear under
the system of pure woods, or at any rate they would not thrive
so well and would not develop equally line boles, as if grown
in mixed woods. Large sized timber of many light demanding
species can only be produced by mixing them with shade
bearing, and consequently soil preserving species.
(r.) Many species suffer less from exteriuxl injurious in-
fluences, such as wind, fire, frost, snow, insects, fungi, if
raised in mixture with other more hardy species. — A shallow
rooted species had best be grown mixed with a deep rooted
species. — Conifers are less exposed to damage by fire or
snow, if mixed with broad-leaved species. — Insects are less
dangerous in mixed woods, as they generally attack only one
of several species ; moreover birds, the great insect destroyers,
are more numerous where broad- leaved trees grow, than in
pure coniferous woods. — Damage by fungi to conifers is also
considerably less if they are mixed with broad-leaved species.
— A hardy species mixed with a tender species protects it
against frost, drouglit and injurious air currents.
DISADVANTAGES OF MIXED WOODS. 73
{(1.) Mistakes made in the selection of species can be more
easily rectified in mixed, than in pure woods. The suitability
of a locality for a certain species is not always apparent at the
outset ; in the case of mixed woods the species which is least
suitable can be removed at the time of thinning,
{('.) For the above reasons, mixed woods will, in many cases,
yield better returns than pure woods.
( /".) Finally, mixed woods increase the artistic beauty of a
countr3\
2. Disadvantages of Mixed JVoods.
It is frequently described as a disadvantage of mixed woods,
that their natural regeneration is more difficult, than that of
pure woods. No doubt, different species require different con-
ditions, if natural regeneration is to be successful. More
especially the cover of the mother or shelter trees must be
more open where a light demanding species is to be regener-
ated, than in the case of a shade bearing tender species. The
shelter, for instance, which suits the beech, would probably
kill young oak seedlings. Again, certain species, such as
spruce, produce so much seed, spring up so easily, and would
take possession of so much ground, that other species, like
silver fir and beech, would have little chance of coming up in
sufficient numbers. In the Black Forest, silver fir has fre-
quently to be helped against the beech. These objections
are undeniable, but they are, after all, not of such importance
as might appear at first sight. In the first place, the mother
trees can be so selected, that one species is favoured against
the others. Secondly, the surplus regeneration of any one
species can be removed in the first thinnings. Thirdl}', the
species can be arranged in small groups. Fourthly and
chiefly, the best procedure is, to regenerate naturally with
special reference to one species, and to introduce the others
(as far as necessary) artificially. In the Black Forest, for
instance, silver fir is favoured in the regeneration, and spruce
is, if necessary, afterwards planted in. In this manner the
forester can produce the desired proportion of the several
74 CHARACTER AND COMI'OSITION OF WOODS.
species with almost miithemalicKl accuracy. On the whole,
mixed woods otier substantial advantages over pure woods.
At the same time it must not be forgotten, that the treatment
of pure woods is much simpler, than that of mixed woods.
Hence, the former may be preferable, whenever really competent
managers are not available.
8. Hull's for the. Foniuttii))! of Mixed Woods.
The advantages of mixed woods, which have been detailed
above, will only be realised under certain conditions, the more
important of which are tbe following : —
{a.) The locality must be, a priori, suitable for the favour-
able development of each of the species in the mixture.
{h.) The mixture must be of such a nature, that the factors
of the locality do not suffer ; they must, whenever possible
be improved. This will only be the case if the principal,
or more numerous, species is soil improving. As indicated
above, exceptions occur when woods are treated under a short
rotation, or when the quality of the locality is such, that it
does not require to be assisted by the improving action of the
trees growing on it.
(c.) The mixture must be so arranged that one species does
not oust the others, and establishes a pure wood. The exces-
sive development of one species may be S.
thrives best on loose, warm, deep soils with a f^ood measure
of water in the subsoil ; spruce recjuires moisture near tlie
surface, and it is satisfied with a moderately deep soil. Oak
requires much light, heat and space : the demands of spruce
are more moderate in these respects. Oak is inclined to
develop large branches; spruce grows nioic in lieiglit. Never-
theless, artificial mixtures of the two species are advocated by
some foresters. Oak grows faster than spruce during youth ;
later on spruce passes the oak, and the latter has no chance
if mixed by single trees in even aged woods. It is necessary
to place the oak in ^loups, and even then it does not always
develop satisfactorily. The best arrangement is to plant oak
pure and to bring in the spruce when the oak begins to thin
out. It has, however, been noticed that the oak becomes stag
headed when underplanted with spruce, a phenomenon which
is l)y some foresters believed to be due to the great consump-
tion of water by the spruce ; hence the mixture is only
admissible under favourable conditions, oi- when the spruce
is cut out at a comparatively early age, before it has liad time
to injure the oak.
(}<(k and s'lInT I'lr. — This is a better mixture than that of
oak and spruce, as the two species resemble each other more
in tlieir demands on the locality. Oak requires a start, or it
will 1)6 passed at about middle age and suppressed by silver
fir. The best plan is to plant oak pure, and to bring in silver
fir when the former begins to thin out.
Oak and Jx'ccli. — This is a most suitiiblc niixtui'e, as the two
species stand sufliciently near each other in re8i)ect of locality
and shape ; moreover, they are found natui-aiiy together. The
beech has l)een called the oak's nurse. The oak finds in the
mixture all the advantages of a permanent complete shading
of the ground, accompanied by a heavy fall of leaves, a thick
layer of humus, and freslnujss of the soil; it tliiis iUtains great
height and a clear bole of considerable length.
Tlu! oak requires to have its head free throughout life. It
trrows more (luicklv than beech if the climate a)id soil suit
SHADE BEARING WITH LIGHT DEMANDING SPECIES. 83
it thoroughly in respect of moisture and depth. In such
locahties the mixture may be arranged by single trees. In
the majority of cases, however, the oak is left behind by the
beech, and then the former, in single trees, is lost ; hence the
mixture must be arranged by groups, or all threatening
beeches cut back or removed ; or the oak is given a start, the
beech being brought in when the oak commences to thin out,
that is to say, between the 80th and 50th year, according to
circumstances.
Oak and hoDihi'um. — This mixture may be desirable in
localities which do not suit the beech, as for instance in frost
localities, or moist deep sandy soils of the low lands. The
oak grows quickly enough to hold its own against horn-
beam. In this mixture the hornbeam is frequently treated as
coppice.
(4.) Nortcay maple and sycamore in mixtare wWi more sliade
hearing species. — Such mixtures require a fresh, deep and fertile
soil. During early youth both maple and sycamore grow more
quickly than spruce, silver fir, and beech, but later on they are
passed by the shade bearing species. Hence, it is necessary
to place the maple and sycamore in groups, or to give them
a start in age; by far the best mixture is that with beech.
(5.) Aslt in mixture witlt sJuide bearim/ species. — The best
mixture is ash and beech ; not so good is that of ash and
silver fir, and still less that of ash and spruce.
Ash, like the maples, grows first more quickly than
beech, but is generally passed by the latter later on, hence
it should be placed in groups in the moister parts of the
locality. Where ash occurs pure, it should be underplanted
with beech or hornbeam long before its height growth has
been completed.
(6.) Kim in mixture with sliade hearing species. — Elm does
best in mixture with beech, or perhaps hornbeam. The
mixture of elm with spruce and silver fir is less desirable.
Elm requires a locality with sufficient warmth, or else it will
not develop into a large-sized tree ; it also requires a deep
81 chakacti:r and composition of woods.
fertile soil. Elm grows at first more quickly than beech, but
afterwards it is liable to be passed, hence it must be placed in
groups, or given a start. The groups of elm should subse-
quently l)e underplanted with beech.
(7.) liiirli in iiii.vtiiii' iritli s]iav
the removal of single trees or small groups selected here and
there over the ^Yhole area, and this process goes on through-
out the whole length of the rotation, so that practically no
part of the whole forest is ever at rest. All age classes, from
one year old to the oldest, are constantly represented, by
single trees or small groups, over the whole area, and, theo-
retically, the work of selecting trees for cutting extends at all
times over the whole extent of the forest. In practice, how-
ever, the forest is divided into a number of blocks, which are
gone over in turn, so that cutting returns to the same part
only after the lapse of several years.
//. Kxternal iJanyen^.
Views differ somewhat regarding the extent to which selec-
tion forests are exposed to external dangers, as compared with
the two previously mentioned slielter-wood systems. In the
absence of exact comparative observations it may be stated,
that in respect of drought the selection system acts very
favourably, because only very small plots are, at one time,
exposed to sun and air currents. The same may be said
in the majority of cases, as regards frost. Nothing definite
can be said in respect of damage by insects. As regards
damage by wind, snow, etc., views differ.
'■. Prodwlioii of Wdod.
Here again actual comparative observations are not avail-
able. It has by no means been proved that less wood per
acre and per annum is produced under this than under either
of the two previous systems. Young growth, no doubt,
develops slowly, as it is much interfered with by the adjoin-
ing older trees, but this may be compensated for by a more
active development, when the trees have secured the full
THE COPPICE HYSTEM. 97
enjoyment of light, especially during the more advanced
period of life. There can, however, be no doubt, that less
clean and shorter boles are produced under the selection than
under the compartment system, though the former is specially
suited for the production of large sized timber, as each tree
can be left in the forest until it has reached the desired
dimensions.
d. Effect upon the Factors of the Localitij.
The system secures an almost absolutely equal degree of
protection of the soil throughout the rotation, more especially
as regards the preservation of an even degree of moisture,
which must act beneficially upon production. Protection is
given not only from above, but the uniform mixture of old
and young trees also secures lateral shelter.
On sloping ground rain water is more effectively retained
under this than under any other system ; avalanches also,
the carrying away of fine earth, landslips, etc., are prevented ;
hence protection forests situated in mountains are usually
worked under this system.
5. The Coppice System,
a. Orkjin and Gharctcter.
Most broad-leaved species have the faculty of reproducing
themselves by shoots, which spring either from the roots,
stool, or stem. After severing the whole, or part, of the
stem above ground, the roots and stool develop shoots, which
grow up into poles, and, under favourable conditions, into
trees, thus producing a new generation. This process of
regeneration can, as a rule, be repeated as long as the stool
and roots continue to live.
When the trees are cut over close to the ground, simple or
ordinary coppice is produced, the shoots starting from a point
which is close to, or in, the ground. Generally, several shoots
spring from the same stool, and these stand in clumps, and
s. U
98 THK sYj,Yicri/rri{AL svstkms.
can easily he distinguislied from seedling trees. On well
stocked areas a complete cover is established earlier under
this system than in seedling forests, as the shoots develop
very rapidly during the first few years. A\'lirL'ricrs.
wliicli is best iidapted to any special set f)f conditions. Tliey
may be bi-onglit under the following headings: —
(1.) Suitability of the system to the selected species.
(2.) The permanent preservation or even improvement of
the factors of the locality.
(3.) Protection against external dangers.
(4.) Safety and simplicity of the method of regeneration.
(5.) Quantity and quality of the produce.
(6.) Intensity of management.
(7.) Existence or absence of forest riglits.
1. SiiitaJiilif// (i/ fht' Si/steiit to the si'Icctctl SjiccieH.
This is a consideration of the first importance in all cases,
where it is desired to grow a particular species. In the first
place, coniferous species cannot be treated as coppice woods ;
while several broad-leaved species, such as beech and birch,
possess only a moderate reproductive power by shoots. In all
such cases only the high forest systems are indicated ; beech
and birch at any rate should not be grown in pure coppice
woods. Again, light demanding species with thin crowns are
but badly suited for ordinary simple high forest ; they should
be raised as standards in coppice with standards, or in two-
storied high forest, or with a coppice underwood, or in mixture
with shade bearing species. Such species are also difHcult to
raise under shelter-woods. On the other hand, tender shade
bearers like beech and silver fir are better adapted to the
shelter- wood systems than to the clear cutting system.
Lastly, whenever a system involves two crops of uneven age
on the same area, the overwood must consist of a thin
crowned, that is to say, light demanding species, and the
underwood of a dense crowned or shade bearing species.
2. I'l-ciniydioii <>/ Oir i'artor^i of thr Loralit//.
On general economic principles, forests should be worked
and managed for a sustained yield, and not for a temporary
CHOICE OF SYSTEM. 109
high return ; hence it is necessary to select a system under
which the factors of the locahty are at least maintained, and
if possible improved.
In the case of exceptionally good localities with a rich fresh
soil and a favourable state of moisture and temperature of the
air, any system can be adopted which answers to the other
requirements of the case. On all localities of only middling
quality, and still more so on poor localities, the first considera-
tion must be the preservation of the factors of the locality, or
else a steady deterioration will set in, which may end in
complete sterility. In such cases clear cuttings must be
avoided as much as possible,'and every effort made to keep the
area permanently stocked with a crop of trees ; in other words,
to regenerate under shelter-woods, so as to lead the old crop
gradually over into a new crop. Unless this precaution is
taken, the degree of moisture in the soil undergoes violent
changes, which act most injuriously on production. The
systems best adapted in such cases are the shelter-wood selec-
tion system, the other shelter- wood systems which produce
an uneven aged young wood, the shelter- wood compartment
system, and coppice with standards.
3. Protection against external Daiajers.
It should be the object of a good management to produce
healthy woods, which are capable of resisting successfully the
dangers to which they are exposed during life. Though
species and method of regeneration are of principal importance
in this respect, the system is also of some account.
Where the object is to counteract the eroding effects of
water running down sloping ground, to prevent the occurrence
of landslips, avalanches, or devastation through shifting sand,
woods of uneven age must be the rule, such as are produced
under the shelter-wood selection system, the group system, etc.
Whether uneven aged woods suffer less from wind, snow
and ice than even aged woods is as yet an open question.
In respect of frost, drought and insects, the clear cutting
IKl THE SYLVICUI/rrifAL SYSTEMS.
system yields the worst results, the shelter- wood compartment
system comes next, and then the systems which produce
uneven aged woods, the shelter- wood selection system being
best of all.
On the whole, localities dill'er nuich ; some larely or never
suffer from storms, snow, etc., while others do so every year.
Such peculiarities must be takeri into account in selecting the
system.
4. Sal'ct/i (Old Siiiijilicitj/ ill' till' Mcllniil nj' l!.) On less fertile soils, which necessitate a careful
husbanding of the factors of production, in the case
of some of the species being light demanding, or under
a high rotation, the systems of uneven aged woods are
desirable.
The former produce principally long and clean timber, the
latter greater girth.
In many cases the objects of management favour the pro-
duction of minor produce, and the system must be selected
accordingly. Where tanning bark of oak is wanted, the
system of coppice is in its place. Osier beds require to be
planted in cleared land. The growth of held crops also is
only practicable under the system of clear cutthig ; at the
outside, only a few standards may be left on the ground.
Where grass and grazing is wanted, the woods should be even
aged, or else the cattle will damage the young trees, etc.
(j. Iittcnsity of Manaiiement.
The more valuable the returns of a forest are, the more
intense, or careful and detailed, should be the system of
management.
The capital invested in a forest differs considerably under
different systems, it being composed of the value of the land
plus the value of the growing stock, apart from buildings, etc.,
which would be required under any system. Hence, high
forest requires a much larger capital than coppice, and often
yields a suialler interest on the invested capital than the
latter.
112 THK SVLVU'l J/rri{AL SVSTK.MS.
Artificial regeneration requires a perioilical outlay of cash
for sowing and planting, while natural regeneration can he
etiected without such outlay, though it may involve a con-
siderable loss of time.
The transport of the material is considerably cheaper in
even aged woods than in uneven aged woods, because in the
former case the operations are more concentrated. The same
holds good as regards supervision.
The shelter-wood systems require more skilled labour than
the clear cutting systems. They also make much greater
demands on the intelligence and industry of tlie manager,
because they require higher skill and more constant sujjcr-
vision.
7. Existence or Absence of llojJits.
In many cases the existence of rights necessitates the
selection of a particular system. For instance, where large
timber has to be provided to right-holders the coppice system
would be inadmissible.
8. !Suin)narij.
Every sylvicultural system has its advantages and dis-
advantages, and it is necessary to ascertain in every special
case, whether the balance of tha two tends towards the one or
other system. From a si/lcienlturcil point oj view, the first
point for consideratitm is the general suitability of the system,
and next the continued preservation and, if possible, improve-
ment of the factors of the locality ; temporary, or immediate,
financial considerations should only prevail in so far as they
do not interfere with the two former considerations.
]1.3
PART II.
FORMATION AND REGENERATION OF WOODS.
115
FORMATION AND EEGENERATION OF
WOODS.
The formation of a wood comprises all measures having for
their object the production of a new crop of trees. Such a
crop can spring up from seed, sHps, layers, pieces of roots, or
from stool shoots and root suckers. In some cases the forma-
tion of a new crop is the result of the spontaneous action of
nature, in wdiich case the forester speaks of natural formation
or rcf/encration ; in others, the seed or young plants are brought
on to the land by the action of man, when the process is called
artificial formation. A further distinction must be made as
regards the special kind of material employed in the formation
of a wood. Again, two or more methods of formation may be
combined. And again, a wood may be composed of a mixture
of two or more species. Finally, certain preliminary works
may have to be carried out before the formation of a wood
can be commenced. Accordingly, this part has been divided
into the following chapters : —
Chapter I. Peeliminary Works.
,, II. Artificial Formation of Woods.
,, III. Natural Eegeneration of Woods.
,, IT. Formation of Mixed Woods.
y. Choice of Method of Formation. -
I 2
116
CHAPTER I.
PRELIMINARY WORKS.
Before a wood can be formed certain preliminary matters
must be attended to. Tbese will be indicated in the following
three sections : —
Section I. — Choice of species.
„ II. — Fencing.
,, III. — Eeclamation of the soil.
Section I. — Choice of Species.
The success of forestry depends in the first place upon a
judicious selection of the species of tree which is to be
grown under a given set of conditions. A full considera-
tion of this matter is of great importance, because mistakes
made in the selection of species cannot, as u rule, be recti-
fied until after a considerable lapse of time. Most indigenous
species thrive almost equally well on ordinary soils for a
series of years, while those unsuited for a particular locality
commence falling off only after perhaps 20, 30 or even more
years.
The fall success of a species depends on many things,
amongst which the following deserve special attention : —
(1.) Suitability for the objects of management.
(2.) Adaptability to the desired sylvicultural system.
(8.) Exposure to damage by external causes.
(4.) Suitability of species for the localit}'.
To which may be added.
(").) Desirability, or otherwise, of a periodical change of
siiecies.
CHOICE OF SPECIES. 117
1. Siiitahiliti/ of thr Species for the Objects of Manaijemoit.
The varying objects of management have been indicated on
page 1. Whatever the.y may be in any special case, the
species must be selected so as to do them full justice.
If the object is to grow produce of a definite description,
the species must be capable of yielding it ; it would be useless
to grow yew for hop poles, or poplar for naval construction.
Where the objects of management are governed, or influenced,
by existing forest rights demanding timber or firewood of a
particular species, that tree must be grown. If, on the other
hand, third persons are entitled to trees of certain species,
should they happen to appear on the area, the owner would
not voluntarily cultivate them.
Where the object is to j)roduce the greatest possible quantity
of material per unit of area, that species must be selected
which produces the highest average annual increment.
In gauging the financial desirability of a species, the
quantity and quality of the produce, as well as the expense
of rearing it, must be taken into account. In some cases
only certain species are saleable, while others are without
value. Again, some species produce a much higher percentage
of timber as compared with firewood, than others.
Species with a thin crown are indifi'erently adapted for wind
breaks, whereas the}' may be specially suited for nurses over
a tender crop, or as standards over coppice.
The above instances will suftice to show that the number of
species which may be desirable in any given case is narrowed
down by the objects of management.
2. Adaptability oj tlic Sjiecies to the desired Sylvicultaral
System.
All species of trees can be treated as high forest, but only
a certain number as coppice woods. The conifers of temperate
Europe either do not coppice at all, or very indifi'erently;
even some of the broad leaved species do not yield satisfactory
118 I'HKIJMINAltY WORKS.
resiill.s. Sliadf Itearinj^ .species are not cle.siral)le as standards
in coppice with standards, A selection of species must be
made accordindv.
3. K.rposiirr of ill)' Sjircirn to l)(iin(«ir h// K.ttcnial ('(Iiihch.
The selection of species to be planted is further narrowed
by the degree to which they are exposed to injury by external
causes, as fire, frost, drought, cold winds, strong gales, insects
and fungi. Conifers, for instance, are more exposed to damage
by fire than broad leaved species ; larch and silver fir suffer
much from canker ; spruce is liable to be thrown by wind ;
beech and silver fir are frost tender, while Scotch pine and
birch are frost hardy ; Scotch pine and spruce are more
subject to damage by insects than any other European
species, etc. All these matters influence the clioice of s^^ecies
under a given set of conditions.
4. Sliildhililil of the Species Jor fJie Loeal'ttjl.
From the point of view of Political Economy the improve-
ment, or at any rate the maintenance, of the j-ield capacity of
the land is the most important consideration. AVhether the
owner of a forest be the State or a private jierson. he will find
a system of management recognising that principle to l)e the
most profitable in tlie long lun. Hence it must be the
forester's endeavour to grow species whicli not only suit the
locality, but also tend to improve it.
In the first place the qualitij of the locality must be carefully
ascertained, so as to avoid growing a species whicli has no
chance of thriving on it. This task is by no means an easy
one, because the efiects of some of the factors of the locality
on tree growth are as yet imperfectly understood. The
climatic factors are of special importance; hence the efiects of
the geographical position, altitude, aspect, gradient, cojitour
ami surroundings of the locality upon the temperature, degree
CHOICE OF SPECIES. 119
of moisture and air currents must be carefully considered.
The soil and, if necessary, the subsoil as well must be
examined as to depth, degree of porosity and moisture, com-
position and admixture of humus. The development of any
trees already growing on the locality, or in its vicinity, should
be carefully studied. An investigation of this kind will
generally indicate what species are capable of thriving on a
locality ; it should, however, not be overlooked that any species
found growing naturally on the area are not always those best
adapted for it, because their presence may depend on circum-
stances other than a general suitability of soil and climate :
for instance, a shade bearing species may have ousted a light
demanding one, or a greater power of reproduction may have
enabled one species to drive out another possessed of less
energy in that respect.
As long as the factors of the locality are fairly the same
over the whole area, the latter may be treated in a uniform
manner, but the occurrence of decided differences may
necessitate the selection of different species for difi'erent parts.
Any attempt at uniformity in spite of such differences may
lead to a serious loss in returns.
In order to provide for a continuous preservation of the
fertility of the locality, it is necessary to select species which
give sufficient shelter to the soil and a good supply of humus,
or, at any rate, to mix such species in sufficient numbers with
those which do not shelter the soil. This rule can only be
disregarded in thoroughly favourable localities. Under these
circumstances, species with dense crowns must receive special
attention in making a selection for middling and inferior
localities ; in addition, interference with the fertility of the
soil, such as the removal of leaf mould, excessive grazing,
faulty treatment, etc., must be carefully avoided. Above all,
personal fancy on the part of the forester for a particular
species must be set aside.
Not unfrequently several species are found to be equally well
adapted for a locality. In such cases other considerations
izO PKEJJMINAKY WOKKS.
ninst decide whicli shall be i^rown, or wlietluM- iown) 'llie natural surface line
is represented by a, a, a, a, while b, 1/ are the places where
the turf has been excavated, and c, c, the dyke consisting of
successive layers of turf.
3. W'dodiii I'aUiKj^.
There is an endless variety of wooden palings.
I '^. ^:^ [^ r-a
I I V V V V V V V V V I
Fig. 8 shows a wooden fence, affording protection against
labbits on one half of the diagram. It sufTers under tlie
disadvantage thai all the upi'i.i^lit s))ars nnist be driven into
FENCING.
125
the ground, which Ccauses them to rot. To reduce this danger
the inserted part should be tarred or creosoted. It is far
better to replace the short spars by wire netting.
Frequently wood fences are made in sections, so that they
can be carried from one place to another.
4. Ditches.
Ditches for keeping out animals should be constructed with
a perpendicular wall (a) on the inside and a gentle slope (h) out-
wards (Fig. 9) ; sometimes the perpendicular side is faced by
a stone wall (r) to prevent its falling in. On the whole, ditches
are expensive, if constructed so as to be lasting ; hence in the
majority of cases they are only used as an auxiliary to other
fences, for instance a wooden paling or a wire fence (d).
0. Wire Fences.
Here, again, a great many varieties have been introduced,
some having iron standards and others wooden supports. In
the case of permanent nurseries iron standards may be desir-
able, but in fencing woods, which only require protection for
a limited number of years while under regeneration, wooden
supports will, in the majority of cases, be found cheaper. On
126
PRELIMINARY WORKS.
the whole, for sylvicnhunil purposes, wire fences with wooden
supports are probably more suitable than any other kind.
Fig. 10 represents a fence consisting of wooden supports,
with six wires so arranged as to keep out horned cattle, horses
and sheep ; height 4 feet, a - - - a shows the surface of the
soil ; h and c the two end or straining posts of a section, which
O/
J
d
iw^ u
Fig. 10.
should not be further apart than ()00 feet ; d, d represent
intermediate thinner posts, placed from 5 to 10 feet apart ; h
and r have each six holes bored into them. At h the ends of
the wires are passed through these holes, bent round the post,
and fastened securely to the wires at c. At the other strain-
ing post, c, the wires are strained and fastened by various
contrivances, one of which is shown in tbe illustration. It
consists of a screwed eye-bolt not less than 12 inches long.
The end of the wire is fastened to the eye of the bolt (Fig.
11, a), and the latter passed through the hole in the straining
post. On th(^ other side a nut. h, is screwed on after lirst
inserting a plate or washer, r, to prevent the luit from cutting
hito the wood. J3y turning the nut sufficiently the wire
FENCING.
127
becomes strained. The wires are fastened to the intermediate
posts by staples (Fig. 12). These are driven half-way into
the posts and the wires passed through, before the straining
commences. They are driven home when the straining has
been completed.
Fig. 13 shows a cast-iron straining bracket fastened to a
wooden pillar ; this is worked with a key. It is used instead
of the eye-bolt.
Where rabbits or hares are to be kept out, wire netting may
be added to the lower part of the fence.
Fiff. 12.
Fiff. U
The cost of the materials in England may be estimated as
follows : —
Wire, imperial standard wire gauge, No. 8, about one
shilling per 100 feet ; galvanised, ^ more. Straining bolts,
12 inches long, |- inch diameter, with nut and washer,
tenpence each. Straining brackets (Fig. 13), tenpence each.
Steel staples, per 1,000, 9s. ; galvanised, ^ more. Thus the
iron materials come to about Sd. a yard, or 4d. if galvanised
wire and staples are used. The cost of the posts and of
labour depends on local circumstances.
For nurseries iron fences may be used, to which wire
netting may be added, if necessary. Fig. 14 represents such
a fence. It is 4 feet high, the pillars are 2^ feet in the
ground, and the fence is strong enough to keep out horned
cattle, sheep, goats, hares and rabbits. The straining pillars.
128
I'RELIMINAKY WORKS.
n. are so iirranged as to strain tlu' wires on liolli sides : they
are usually, in this fence, placed 220 yards apart. The stan-
dards, /^ are tee-irons, 1^' x li" x ^'jv", placed 12 feet
apart. The top wire is fT'^lviinised barb No. 4, the three
lower wires No. (> galvanised strand. The netting is li inches
mesh, medium quality; it reaches 3J feet above ground, and
is pegged down 0 inches along the surface outside, to
prevent rabbits burrowing under it. This fence is offered in
the London market for l.s-. -ild. a yard.*
6. C()iiihiiiatio)is.
Frequently two kinds of fences are combined. More par-
ticularly wooden palings or wire fences or even turf dykes
and walls may be added to ditches, or walls and turf dykes
may carry a wire fence or a wooden paling (see Fig. !)).
7. Choirr of Fence. ■
The choice of fence depends chiefly on :
(1.) The time durhig which it is required.
(2.) The species of animal to be kept out.
If an area is to be protected permanently, or at any rate
during a considerable period of time, the fence should be of a
substantial nature, such as a living hedge, wire fence with
* I5y tlic Iron Wire. Wire Hn|)0, and Foiieiiig t'oniiKiny. Westminster.
RECLAMATION OF THE SOIL. 129
iron standards, or stone wall. For a limited number of years,
wooden palings, a wire fence with rough wooden standards, or
a turf dyke will be cheaper.
Protection may be provided against horned cattle, horses,
sheep, goats, and deer by any of the above-mentioned fences.
Where hares and rabbits are to be excluded as well, wire
fences, and often also hedges and wooden palings, require the
addition of wire netting, or a similarly effective arrangement.
In the case of rabbits and hares only, wire netting, with cheap
standards, suffices ; the wire netting must go from 6 to 12
inches below the surface ; a still better arrangement is to lay
it flat on the surface on the outside for 6 to 12 inches and cover
it with soil or turf.
Against ordinary cattle a height of 4 feet is sufficient, but
against deer the fence should be 6 and even 7 feet high.
Section III. — Eeclamation of the Soil.
Soil may be called fertile for sylvicultural purposes, if it
possess sufficient depth, a suitable degree of porosity and
moisture, and a suitable chemical composition. Forest
soil, if undisturbed, will in most cases maintain, or even
acquire, those physical conditions which render regular arti-
ficial tillage unnecessary. Immediately before and during
the formation of a wood, however, certain things may have to
be done to render the soil fit for the growth of trees. These
measures may be divided into the following two groups : —
(rt.) Eeclamation of soil unfit for the growth of trees, and
(h.) Tillage of the soil concurrent with the formation of
a wood.
The latter will be dealt with in connection with the various
methods of starting a wood. Group (a) includes the following
measures : —
(1.) Treatment of an impermeable substratum.
(2.) Treatment of swampy ground generally.
(3.) Irrigation of arid land.
s. K
130 PRELIMINARY WORKS.
(4.) Treatment of excessive laj-ers of vegetable matter.
(5.) Fixation of shifting sand.
(6.) Fixation of unstable soil on slopes.
It would require a volume to itself to deal exliaustivelj-
with these matters; hence, in this place, only a few short
remarks can be made on the more important points.
Those who require more detailed information will find
it in Volume IV. of this Manual and in special works on
the several subjects.
1. Treatment of an Impermeable Suhstratiim.
Impermeable strata in the soil consist in some cases of an
accumulation of cla}', which has bj^ degrees been washed out
of the surface layers and deposited at a certain depth ; in
other cases sand or gravel has been converted into a hard
rock-like mass by the addition of organic matter, clay, or
oxide of iron. Such a stratum is frequently called a jmn. It
may be found at varying depths below the surface ; if at a
depth of 4 feet or more, it does not, as a rule, interfere with
the growth of forest trees, except perhaps on arid unirrigated
ground, but if it occurs nearer the surface it may produce the
following injurious effects : —
(a.) Interference with the development of a proper root
system, followed by small height growth and liability
of the trees to be thrown by strong winds.
{h.) Interference with the movement of water in the soil,
preventing its penetration into the subsoil during wet
weather, and its ascent during dry weather ; in other
words, it may render the soil too wet at one time and
too dry at another.
The remedy is to break through the impermeable stratum,
so as to connect the upper and lower permeable layers of the
soil. According to the nature of the pan and its depth below
the surface one of the following methods of treatment must
be adopted : —
(a.) Deep ploughing.
RECLAMATION OF THE SOIL. 131
(/>.) Trenching.
{(■.) Raising the surface level.
If the lowest part of the pan is not deeper than 18 inches
below the surface and not too hard, ploughing may be adopted ;
the pan, being brought to the surface and exposed to the
atmosphere, soon disintegrates. Pans situated at a greater
depth than 18 inches must be broken through by trenching
with spade, hoe, pick, or crowbar. In either case the operation
is expensive, hence it is usual to treat only part of the area,
in strips, patches, or holes. Strips may be 2 to 3 feet
broad, separated by unbroken ground 4 to 6 feet in ])readth,
so that the actual work is restricted to about one-third of the
area. Patches may be of various sizes, down to holes about
12 inches square.
If the pan is very thick and goes to a greater depth than
3 feet, it may be cheaper to raise a portion of the land by
cutting ditches at intervals and placing the excavated earth
on the intermediate strips, thus providing the latter with
a depth of soil sufficient for the production of trees.
The treatment of impermeable strata is always an expensive
matter, so much so in many cases that the utilisation of the
area becomes altogether unprofitable. In some cases the
expense may be avoided by planting a shallow rooted species
and being satisfied with moderate returns,
2. Treatment of Swampy Ground generally.
Each species thrives best with a definite degree of moisture
in the soil at all times of the year. That degree differs con-
siderably in the case of the several forest trees ; while some
like moist and even wet soil, others will not flourish in such
localities, and none of them in stagnant water. It follows
that an excess of moisture, over and above what is suitable
for a given species, must be removed before a wood is started.
The method of doing this depends on the cause of the excess
of moisture.
A locality becomes swampy if it receives more water than
k2
I.'i2 PRELIMINARY WORKS.
can 1)0 disposed of ]>\ evaporation, lilterinj:^ inio the snl)soil,
or surface drainage. An excess of water may be due to ex-
cessive rainfall, inundation, underground currents, or springs;
in the first two cases the swampiness may be only temporary.
The natural draining away of the excess water may be im-
peded by an insufBcient local gradient, by an impermeable
soil, or by both combined, the last being the usual case.
]3efore removing the surplus water from a swampy piece of
ground, the expense and the effect of drainage on the sur-
rounding lands should be carefully considered. The cost is,
as a rule, considerable and sometimes prohibitive ; draining
a swamp may, especially in a hilly country, seriously reduce
the necessary degree of moisture of adjoining areas, the level
of underground water, the continuous flow of water in the
ordinary water channels, or even the amount of rain and
dew in the neighbourhood. Existing woods, which have
become accustomed to a certain degree of moisture, may
thus be seriously injured.*
If, after full consideration, it has been decided to remove
the excess water, this can be done either by diverting the
water l)efore it reaches the swampy ground, or l)y draining
the latter.
a. Dirrrfiion of Jurrss Wr/fcr.
This is done by embankments in the case of inundation
water coming from rivers in low lands, or by ditches in the
case of spring water or surface drainage coming from higher
ground.
Inundation water moving over the surface of tlie land may
be kept out of a certain locality by a surface embankment ;
if the water moves underground, it can only be stopped by a
substantial underground embankment, such as a stone or
concrete wall.
Spring water and surface drainage in hilly ground is caught
* It is belic-vfd that sonic of ihv finis in tlic Lonjr AValk. Windsor Vixrk.
died in cojisciiuiiici' of (ir!iinat,'t' can ird out sonic tinieajro; after tliese drains
liad. ill consciincncc. bt'eu blocked again, the remaining trees recovered.
RECLAMATION OF THE SOIL.
133
and diverted by runniiif:; a ditcli of suitable dimensions
along the slope of the hill just above the swampy ground.
The ditch intercepts the water and leads it past the swamp.
In cases where the spring is situated in the swampy ground
itself, only draining can meet the evil.
h. Drainage.
A swamp may be drained : —
(1.) By increasing the gradient (or width) of existing water-
courses. This is practicable when the latter pursue a winding
course ; in such a case the course may be straightened, so as
Fiff. 15.
to increase the velocity of the current. This method is only
occasionally applicable.
(2.) By breaking through an impermeable stratum in the
soil, so that the water can j<er into the subsoil (Fig. 15).
Here a represents the water, h and d permeable strata, and
c an impermeable stratum ; e the channel leading from the
swamp to the lower permeable stratum.
(3.) By constructing a series of ditches, or laying down a
series of drainage pipes. The latter are rarely used in
forestry, because they are expensive and liable to be choked
by the roots of the trees. For the same reasons covered
ditches are only rarely employed. The method usually
followed consists in the construction of a series of open
ditches, because they are comparatively cheap, whilst setting
134 PRELIMINARY WORKS.
aside a portion of the area for ditclies does not reduce the
returns.
There may be three kinds of ditches : —
(1.) The collecting ditches, or feeders ;
(2.) The connecting ditches, or leaders ;
(3.) The main drain.
See Fig. IG.
The feeders receive the water from the soil and conduct it
to the leaders, whence it is taken into the main drain. In
some cases the feeders fall directly into the main drain.
The first step in proceeding to drain an area is to take
levels, so as to ascertain accurately the fall of the locality ;
if the area is of some extent, a map showing contour lines
should be prepared. Unless this is done, mistakes are
likely to occur in laying out the system of drains.
The second step is to lay out the main drain, if possible
along the natural line of drainage ; in other words, along the
lowest part of the area. According to the natural fall of the
land, the gradient of the main drain may have to be in-
creased by cuttings, or reduced by giving it a winding course,
so as to secure a suitable fall.
The third step is to lay out a system of feeders, more or
less parallel to each other, at a suitable angle with the
general slope of the country, and to connect them at an
acute angle with the main drain, either directly or through a
leader, which is similarly connected with the main drain.
In laying out such a system of drains, the gradient,
depth, shape and distance from each other require careful
consideration.
The gradient, or fall, should be such that the water is
carried awa}' with sufficient rapidity, without causing injury
to the base and sides of the drains by the scouring action of
the water. AVliere the natural gradient of the ground is in-
sufficient, the base of the drain must bo sunk until the
necessary fall has l)een obtained. A\ here it is too great, tlie
drains must pursue a winding or zig-zag course, so as to
RECLAMATION OF THE SOIL.
135
reduce the fall ; or the base and sides of the drains must be
protected by a facing of stone, or fascines ; in some cases the
base may be terraced.
a, a. Contour lines,
c, c. Wiiter parting.
h. Feeders.
Fig. 16.
c. Leaders.
d. Main drain.
(The figures 170, 160, 150, and 140 give the elevation in feet above sea-level.)
The maximum gradient which is admissible depends on
the nature of the soil. Where the latter is of middling con-
sistency an average fall of 1 per cent, would probably be
136
PRELIMINARY WORKS.
indicated ; on firm soil it may be greater, on loose soil
smaller.
The dcptli of the feeders depends on the depth to which it
is intended to drain the land ; the former must be somewhat
greater than the latter. The depth to which the soil requires
draining may vary from 18 inches to 3 feet, according to the
species to be grown. Ash, hornbeam, and elm can do with
18 inches, while Scotch pine, beech and silver fir, prefer soil
which is drained to a depth of 3 feet.
u
a, a. Natural level of ground.
h. Feeder, four feet deep.
c, c. La}-er.s of soil actually drained.
Fiff. 17.
(/, (/. Layers of .soil not drained.
( Id c. About three itet.
Fig. IS.
a. a. Natural level of ground.
h, b. Leaders (five feet deep), or main drains.
c, c. Feeders. Depth at upper end, 3 ft. G in., at lower end, 4 It. U in.
(In these diagrams tlie height is exaggerated.)
Figs. 17 and 18 illustrate the comparative depth to which
a locality is drained, and that of the feeders and leaders.
The sha2)e of the drains depends on the fall and on the
nature of the soil ; the greater the cohesion of the latter, the
steeper may be the slopes of the sides. In the case of peat,
the sides may be almost perpendicular, in stift' loam they
should I'urui an an<^ie oi' uljout 15 degrees, and they must
become more and more slanting, as the proi)ortiun of sand in
the soil increases. The base of the ditch should be at least
as broad as the spade which is used in making and after-
RECLAMATION OF THE SOIL. 137
wards cleaning it. For the rest, the width of the drain
depends on the body of water which has to be carried away.
The distance between two successive feeders depends on the
permeabihty of the soil, the depth of the ditches, the depth
to which the land is to be drained, and the general fall
of the locality ; it will accordingly range between 30 and
100 feet.
c. Raising the Level of Fart of tlie Ground.
If it is undesirable or impracticable to drain a swampy
area, it may, if the water is of moderate depth, nevertheless
be rendered useful, by excavating part of it and using the
soil so obtained to raise the level of the rest to a sufficient
height so as to render the cultivation of trees practicable.
a — a. Natural level of swampy groiind.
h, h, h. Ridges on which the trees are to be planted.
In such cases the raised parts form generally parallel ridges,
as indicated in Fig. 19.
Such works are expensive, and only species which stand
a good deal of moisture can be grown.
3. Irrigation of Arid Land.
In temperate Europe irrigation is only employed in
nurseries, but in more southern, tropical and arid countries
extensive areas are artificially irrigated for the growth of
forest trees. The details of irrigation must be studied from
a special work on the subject.* In a general way, irriga-
tion may be described as the reverse of draining; thus in
Fig. IG (page 135), d Avould represent the main supply
* For instance. " The Roorkee Treatise on Civil Engineering in India."
Vol. ii., Section x.
138 PRELIMINARY WORKS.
channel, situated in the liighest part of the area, c, c, c
the leaders, and h, h, h the distributing trenches. The
watering of the land may be caused by overflow from the
trenches, or by percolation ; in the latter case the trenches
would only be just filled, and no more.
"Where extensive areas are to be irrigated, the channels and
trenches must be carefully laid out, with a suitable fall, so as
to prevent the bursting of the channels and the silting up of
the trenches.
4. Treatment of Excessive Accumulations of Vegetable
Matter.
Cases occur in which accumulations of vegetable matter
have to be disposed of, before the formation of a wood can
be taken in hand. Such accumulations may be objectionable,
because they are so thick that the seedlings cannot reach the
mineral soil within'a reasonable space of time, and run the risk
of drying up ; or they may have become acid, or bituminous ;
again, they may be accompanied by swampiness, or be liable
to dry up too quickly.
The following cases specially interest the forester : —
a. Peal Bogs.
To render a peat hog fit for the growth of timber trees,
one or all of the following operations must be carried out : —
(1.) Draining.
(2.) Removal of at least a portion of the peat.
(3.) Mixing the peat with mineral soil.
The draining is done in the manner described above ; it is,
however, desirable to do this gradually, so that the layers
of peat may dry by degrees, to prevent the formation of ex-
tensive cracks. The feeders should at first be of moderate
depth, and gradually deepened, until the mineral soil is
reached.
AVhen the layer of peat is sliallow, it can, after draining,
be mixed with the mhieral soil below it, and thus rendered
EECLAMATION OF THE SOIL. 139
fit for the growth of trees ; a good plan is to grow one or two
field crops on the area, before the trees are planted.
If the layer of peat is deep, 3 feet and more, the upper
portion must be removed, and only the remainder mixed with
the mineral soil. The cut peat may be used as fuel, but if
not so required, it may be cheaper to burn the upper layers
in situ when sufficiently dried by the draining, the ashes
being mixed with the soil.
h. Accumulation of Raw Humus.
This may consist of an accumulation of leaves, needles,
weeds, moss and twigs, which, from want of moisture in the
soil, or of heat or lime, has remained undecomposed. The
case only occurs in already existing woods. To cure the evil,
the wood must be thinned heavily, some time before regenera-
tion is contemplated, so as to increase the admission of sunlight
and air currents and accelerate thereby decomposition. If
this measure proves insufficient, part of the humus must be
removed, and the rest mixed with the mineral soil.
c. Dry Mould and Bituminous Humus.
The first is formed by the decomposition of certain lichens
on over- dry soil ; the latter is the result of the decomposition
of heather and various species of Vaccinium. Both are
unsuited for young plants, and they should be removed.
On the whole the cases mentioned under h and c occur
but sparingly.
5. Fixation of Shifting Sand.
Sand of a fine grain, without a sufficient quantity of
binding material such as clay or humus, is liable to be
blown about, and to become moving or shifting sand, which
overspreads adjoining lands. If the supply is kept up, these
shifting masses of sand form regular waves which proceed at
a certain rate in the same direction as that of the prevailing
wind. Shifting sands are most prevalent along sea shores,
140 PRELIMINARY WORKS.
but occur also inluiul. In eitlier case, but especially near the
sea, they are capable of forming considerable accumulations
of sand, reaching a height of 200 feet and even more, which
are called dunes. Before such areas can be brought under
wood, it is necessary to fix them, so as to allow trees to
spring up and lay hold of the soil permanently.
a. Coas/ Dunes.
Along the sea coast the waves constantly throw up sand,
which, after drying, is carried inland by air currents, forming
a series of ridges and valleys in many cases, though not
necessarily, parallel to the sea shore. These sand hills move
steadily forward, being replaced behind by fresh sand thrown
up by the sea. The rate of progress varies considerably
according to circumstances. On the west coast of France it
is said to be about 14 feet a year, but as the process has gone
on for a long period of time, an enormous area comprising
millions of acres has become covered with sand. The further
progress of the evil has been checked only in comparatively
recent times by operations which it is useful to describe
shortly in this place.
The measures which must be taken are : —
(1.) Cutting off a further supply of sand from the sea.
(2.) Fixing the sand temporarily, so as to allow sowing or
planting.
(3.) Growing a crop of trees and bushes, which will per-
manently fix the sand.
(4.) Maintaining permanently a crop of trees and shrubs.
The first of these four measures is based on the fact that,
although air currents are capable of moving the sand along
level and gently sloping ground, they cannot lift it above a
certain height. Hence it is necessary, at a moderate distance
(100 — 300 feet) from high water level, to form an artificial
hill, which is high enough to arrest the forward movement
of the sand, and this is done by the construction of an artificial
dune, generally called the "littoral dune." With Ibis object
KECLAMATION OF THE SOIL.
141
in view a continuous line of paling is erected, consisting of
planks about 6 feet long \)y 6 inches Avide, 1 inch thick, and
pointed at the lower end. The planks are inserted into the
ground to about half their length, an inch apart, the direction
of the line being parallel to the coast. Against this fence the
sand is deposited, a certain portion being forced through the
Fig. 20.
a. Sea level.
b. Paling iu three successive positions.
c. First wattle fence,
d. An additional wattle fence.
e. Original surface of littoral dune.
/, ff. Surface of littoral dune in two subsequent stages.
(The heights are exaggerated.)
interstices and coming to rest in the comparatively quiet air
immediately behind the paling. As soon as the accumulation
of sand approaches the upper ends of the planks they are
pulled up about 3 feet by means of levers, and this process is
repeated until the artificial dune has reached such a height
that no sand can be carried over the top (see Fig. 20).
Simultaneously with the first erection of the paling a wattle
142 rRELTMINARY WORKS.
fence is placed at a convenient distance behind it, to prevent
the sand which has passed through the pahng from being
carried inland ; when the first wattle fence has been entirely
covered, a fresh one is made to replace it. In this way the
dune is forced to adopt a moderate slope on both sides, which
is essential to its permanent maintenance. The latter is
effected by growing on it certain plants which are capable of
living under such conditions. Amongst these the marram
grass, Psamma {Ammoph'da) arcnaria, takes the first place ;
it has the property that, as the sand rises around it, its stalk
grows higher and develops numerous adventitious roots at
the joints. Other plants used for the same purpose are
Eli/nnts arcnarius and Care.v arouivia.
The second measure, or the temporary fixation of the area
covered with sand behind the littoral dune, consists in
covering the area with various materials, such as the
branches of coniferous trees, heather, broom, furze, seaweed,
turf, etc. ; the last, when obtainable, is best. These materials
(except the turf) are kept in their place either by fastening
them down with pegs, or by placing shovelfuls of sand
upon them.
The third measure consists in stocking the temporarily
fixed area with trees, shrubs, and grasses. Of trees the
Scotch pine and the cluster pine (Pin us Pinaster) are specially
adapted ; seed of these may be sown or transplants put in.
Of other plants Psamma arcnaria, Eh/miis arcnarius, Carcx
arenaria, broom {Sarothamnus scoparius), and furze {Ule.v
nana), may be mentioned. It is essential to maintain the
temporary cover until it is replaced by the permanent growth.
On the west coast of France the second and third measures
are done simultaneously. There, a mixture consisting of
9 pounds of cluster pine seed, 8 pounds of broom, and 3^
pounds of I'samiiia arcnaria per acre are sown, and im-
mediately after it the ground is covered with brushwood,
which is kept in its place by occasional shovelfuls of sand.
The })ineK, the broom, and the marram grass come up
RECLAMATION OF THE SOIL.
]43
together, and it is said that the young pines grow all the
better when surrounded by the two other species.
The cost of these operations is considerable, amounting
sometimes to ten pounds per acre and more ; the expenditure
will not be found excessive, if it is remembered that fertile
lands beyond the dunes may thus be protected against being
covered by sand.
I). Inland Dunei<.
These are treated in a manner similar to that described in
the case of coast dunes, with this exception, that the con-
struction of a forward dune,
corresponding to the littoral
dune on a sea shore, may not
be necessary. In many cases
it may suffice to arrest the for-
ward movement of the sand
on the windward side by a
wattle fence until the ground
has been covered with a growth
of trees, shrubs and grasses. The temporary fixation of the
sand is here frequently effected by means of pieces of turf,
which are laid in rows or squares, within which the sowing
or planting is done (Fig. 21).
In the case of both coast and inland dunes it is essential
to keep all domestic animals out of the area, at any rate
for a number of years after it has been fixed, as they disturb
the sand. When the area has been stocked with ti-ees, clear
cuttings must be strictly avoided, the wood being treated
under the selection system, else the work may have to be
done over again.*
6. Fixation of Unstable Soil on Slopes.
Owing to the action of water, soil on sloping ground may
become unstable. Water filtering downwards causes a re-
duction in the cohesion of the different layers of the soil,
* For further details see Volume IV. of this Manual.
144 rRELnriNARY works.
followed by <];raclual deniulation, or landslips. In water
channels the banks may be undermined. The result is a
reduction in the productive power of the slopes, while the
level ground l)elow may be covered with the del)ris brought
from 'above ; at any rate the water channels in the low land
silt up, and give rise to inundations.
The detailed consideration of this subject belongs to Forest
Protection.* It will suffice here to state that the best pre-
ventive measure consists in keeping such ground permanently
under forest growth, from which domestic animals sliould be
excluded.
If a bare area exposed to denudation is to be stocked, it
may be necessary to fix the soil before sowing or planting is
attempted. This is done by regulating the existing water
courses, terracing them, and even erecting wooden or masonry
revetments. Where necessar}-, additional water channels
must be cut to lead off all surplus water into the regular
channels. Cattle of all kinds must be strictly excluded.
The land itself may have to be terraced, or wattle fences may
be erected at suitable intervals. Only after the soil has been
rendered stable can the formation of a wood be commenced.
Works of the above mentioned kinds have been executed on
a large scale in the French, I Swiss and Austrian Alps,
as well as in the Jura.
* For further details see Volume IV. of lliis Manual.
t See " Traite pratique du Reboisenient et du Gazonnement des Montagnc.*,"
by P. Demontzey. Paris : Rothschild, 13, Hue des Saints-Peres.
145
CHAPTER II.
AETIFICIAL FORMATION OF WOODS.
Section I. — Direct Sowing.
By " direct sowing " is understood the formation of a wood
by the sowing of seed directly on the area which it is proposed
to stock. This can be done in various ways. Whatever the
chosen method may be, its success depends on considerations
which hold good, more or less, for all ; hence, the general
conditions of success must be dealt with, before a description
of the different methods of sowing can be given.
A. Conditions of Success.
1. Choice of Species.
The considerations which guide the forester in the selection
of the species to be grown have been given in chapter I. In
this place attention must be drawn to the fact, that under the
system of direct sowing only a moderate amount of protection
can be given to the seed in the ground and to the young seed-
lings which may spring up. Trees with delicate seeds and
seedlings, or expensive seeds, are, therefore, less suited to this
method than hardy species which thrive easily, and especially
those with large seeds.
2. Qualitij of Seed.
It is of paramount importance to use only good seed. The
quality of the seed depends principally on its being perfectly
ripe and on its weight, size, age and origin.
a. Weight and Size.
In the case of one and the same species large heavy seeds
are better than small light ones. The former generally
s. L
146
ARTIFICIAL FORMATION OF WOODS.
possess a greater germinating poNver, and the resulting seed-
lings show a greater power of resistance against external
injurious influences, and a more vigorous development, which
in many species is due to the greater quantity of reserve
materials deposited in the seed. This superiority at the first
start should not be under-estimated, because it is recognisable
long after the seedling stage has been passed. In many cases
the dominating trees grow out of the seedlings which had
the best start.
The actual weight of good seed varies according to locality.
The following figures are given as examples ; they represent
averages for clean seeds without wings calculated from the
best available data : —
Number of Seeds
per pound.
Sweet chestnut 115
Oali, pedunculate
Oak, sessile
130
IGO
Hazel
420
Beech
2,000
Maple (sycamore)
Ash
5,000
6,500
Lime, broad-leaved
5,000
Lime, small-leaved
15,000
Hornbeam
15,000
Common elm .
00,000
Alder, common
300,000
Birch
Silver fir .
Austrian pine .
Weymouth pine
Corsican pine .
. 800,000
10,000
24,000
28,000
. 32,000
Douglas fir
Spruce
. 40,000
. G5,000
Larch
Scotch pine
. 70,000
. 75,000
DIRECT SOWING. 147
b. Age.
The germinating power of seed is greatest immediately
after ripening ; it can be maintained for a shorter or longer
period according to species and treatment. It follows that, the
sooner seed is sown after ripening the better. This becomes
absolutely necessary in the case of elm seed, as it only keeps
for a very short time. The seeds of birch, alder, silver fir,
sweet chestnut, beech and oak may be kept until the following
spring, but on no account should seeds of these species be
used more than six months old. In the case of lime, horn-
beam, maples, ash, larch, spruce and Scotch pine seed up to
two years old may be used ; if older it should be rejected.
When seed is stored it must be kept free from moisture,
and protected against heating by keeping it in an airy locality
and turning it over from time to time.
c. Source.
The source whence seed has been obtained is of importance.
Although trees of all ages can yield excellent seed, as a general
rule it may be said that, the best seed is derived from trees
which are in the prime of life, namely, healthy trees with a
full crown, which have just completed their principal height
growth. At the same time, soil and climate, and especially the
latter, are of greater importance than the age of the trees.
The question has been raised, whether it may be advan-
tageous to obtain from time to time seed from another locality,
as is done in agriculture. This may become desirable when
the trees are affected by disease or by peculiarities which are
transmitted through seed, as for instance twisted fibre ; apart
from such cases, it is probably better not to change the seed.
Trees live for a long space of time, and they accommodate
themselves to a locality, so that home seed is likely to do best.
d. Testing Seeds.
The quality of seeds can be judged by their external and
internal appearance. Good seeds fill up the outer coat, are
l2
148 ARTIFICIAL FORMATION OF WOODS.
of a good rich colour, possess a healthy smell, and look fresh
in the interior when cut open. The percentage of good seed
can, in the case of heavy seeds such as acorns, sweet chest-
nuts and beech nuts, be judged l)y putting them into water,
when those properly developed will sink, while the bad and
inferior ones will rioat on the surface.
When accurate information is required, regular germinat-
ing tests must be applied. These consist in subjecting a
certain number of seeds, usually 100, to conditions which
secure quick germination, namely a steady degree of moisture,
a temperature of 60 — 70 degrees Fahr., and free admission of
air. Any arrangement which secures these conditions will
do ; as instances the following may be mentioned : —
The Pot test. — Fill a shallow, porous flower pot w^ith loose
earth, place the seeds on the earth, cover them with some
moss, maintain an even temperature, and water periodically,
or better still, place the pot inside another containing water.
The seeds should be removed as they germinate, keeping an
account of them day by day.
Tlw Flannel test. — Place the seeds between two pieces of
flannel, or Altering paper, maintain an even temperature, and
water steadily either by a spray or by connecting the flannel
with a dish of water.
Of late years a considerable variety of germinating dishes
have been invented, but it is doubtful whether any of them
surpasses the more primitive tests described above, especially
the flannel and filtering paper tests.
The percentage of seeds tit to germinate differs much, not
only according to species, but also in diti'erent samples of
seed of the same species. Seed may be considered good if
a carefully conducted germinating test gives the following
percentage of germinable seeds :—
Spruce 75 per cent.
Austrian pine . . . |
Scotch pine . • • . ■ . 70 .,
Corsican pine . . . '
DIRECT
SOWING.
Hornbeam
Oak ....
. 65 per cent.
Ash ....
)
Sweet chestnut
. 60 „ „
False acacia .
I
Maple (sycamore and Nor
way)
j
• 55 .,
Weymouth pme
i
Lime ....
. 50 .. ,.
Beech ....
)
Silver fir . . .
.
. 40 .. ..
Larch ....
• 35 ,, ,.
Elm (common and mountain)
[
Alder, common
. 30 ,. ,.
Douglas fir .
)
Birch ....
. 20 „ „
149
3. Qucmtiiy of Seed.
The density of a forest crop should be sufficient, on the one
hand, to give a proper shelter to the soil, and, on the other,
to provide for each tree that gro\Ying space which is best
suited for its proper development. The first object will be
obtained by thick sowing, but in that case the development of
the trees would soon be interfered with ; hence a mean must
1)6 struck ; in other words, the density of the 3'oung crop should
be such that a fair cover overhead will be established within
5 — 10 years after sowing. This consideration governs the
quantity of seed to be sown per unit of area. The actual
quantity depends on the qualit}^ of the seed, the nature of the
soil, the mode of growth of the species, and the dangers to
which the seed and the young seedlings are exposed. Of these
the quality of the seed has already been dealt with.
The Soil. — Almost any soil can nourish a full crop of seed-
lings, so that the chemical composition of a soil becomes of
importance only after the young crop has closed up and the
struggle for existence commenced. Of far greater importance,
150
ARTIFICIAL FORMATION OF WOODS.
durinp; germination and the early stage of life, are a proper
degree of moisture, heat and porosit}-. A dr}-, loose, stony
soil, and again a hard, cold soil, requires more seed than a
fresh soil of middling porosity.
The Mode of Grouth. — In the case of species which are of
quick growth during youth less seed is required, than for
others which grow slowly at first and do not close up for some
time.
External Dangers. — The seeds are liable to be eaten by
animals. Amongst these birds are most injurious. To
protect small seeds against birds they may be coated with red
lead. Mice may be caught in traps or poisoned. The
young seedlings are subject to injury by animals, fungi, the
effects of climate such as frost, drought, excess of moisture,
and they are liable to be choked by weeds. The quantity of
seed to be sown is governed by the extent to which such
injuries may be expected to take place in any given locality.
Although it is, therefore, impossible to give the actual
quantity of seed required in any particular case, the following
figures may be taken as illustrating, under average conditions,
the necessary quantities in the case of broadcast sowing, the
seed being of good quality and clean : —
Oak
Beech
Hornbeam ]
Ash . j
]\raple . ^
Birch .
Elm
Alder .
Silver fir
Larch
Spruce .
Scotch pine
Quantity of Seed in
i'ouiuls |ier Acre.
. 550
. 150
35
30
25
15
10
14
10
G
DIRECT SOWING. 151
In the case of partial sowing the quantity of seed is
proportionately smaller, thus for
Sowing in strips, furrows,
or trenches about 65 — 70 % of broadcast sowing.
,, ,, patches . . 50 ,, ,, ,,
,, ,, pits or holes . 25 — 35 ,, ,, ,,
4. Conditions of Germination.
The process of germination is as follows : —
(1.) Swelling of the seeds.
(2.) Chemical change of the nourishing substances
deposited in the seed.
(3.) Development of the embryo.
The swelling of the seed is due to the absorption of water.
If then a sufficient amount of heat and oxygen are available,
the reserve materials are changed into soluble substances fit
for the formation of new cells ; growth then sets in, which
causes an enlargement of the embryo followed by the bursting
of the shell of the seed and the protrusion of the rootlet.
The conditions for the successful germination of forest
seeds are thus : —
(1.) A constant but moderate supply of water.
(2.) A temperature not lower than 45°, but better from
55—75° Fahr.
(3.) Admission of air, whence the oxygen is derived.
The presence or absence of light is of no importance.
These conditions can easily be provided in the case of
small experiments, but in operations conducted on a large
scale they can only to a certain extent be secured by a
suitable condition of the germinating bed, by the manner
of covering the seed, and by sowing at the most suitable
time of year.
a. The Germinating Bed.
A suitable condition of the germinating bed is of prime
importance ; it is secured by working or loosening the soil, in
152 AUTIFICIAL FOltMATlUN Ol' WOODS.
some instances by draininfi; or irrigating, and in exceptional
cases by manuring.
Loosening the soil secures the following advantages: —
(1.) It enables the roots to spread more readily, and
to penetrate deeper into the ground, thus rendering
the young plant more independent of variations of
moisture in the surface soil.
(2.) It effects a mixture of the different layers of the soil,
thus rendering the nourishing substances more readily
available and causing greater activity in chemical
changes.
(3.) It freely admits air and heat.
(4.) It exercises a favourable effect upon the degree of
moisture in the soil. Rain water penetrates more
readily and to a greater depth, while subsequently,
during dry weather, it rises again by capillary
attraction.
On the other hand the following drawbacks must be
mentioned : —
(1.) On steep slopes loosening the soil may be followed by
denudation, as rain water can more easily carry it
away.
(2.) Frost lifting may occur more frequently.
(3.) It may attract injurious insects, such as the cock-
chafer, the larva? of which are very destructive to
the roots.
The degree of loosening, and the depth to which it may
reach, depend on the original condition of the soil. Hard
or wet soil requires more, naturally loose soil less or no
working.
In some cases the actual process of loosening the soil must
be preceded by the removal of an obstructive surface covering,
such as woody shrubs, weeds, grass, moss, ferns, heather,
raw humus, etc. ; in other cases this is not necessary. The
loo.:ening itself can be done in a variety of ways ; l)y means
of tools, sucli as the plough, harrow, rake, hoe, or spade; l)y
DIRECT SOWING. 153
allowing it to be broken up by swine ; or by a temporary
cultivation of field crops. Whether the one or other is prefer-
able depends on the method of sowing and the cost of the
operation.
Too much moisture may prevent or retard germination,
may obstruct aeration of the soil, or render it cold and cause
the seed to rot. These inconveniences can be prevented either
by a better distribution of the water, or by draining. The
latter plan should be restricted to cases where the moisture is
really excessive, and where no injurious effect upon adjoining
areas is likely to be produced. In forestry it is better to
drain too little than too much ; in manj^ cases the forester
will do well to be satisfied with a species which will grow in
moist or wet soil, rather than endanger the proper develop:-
ment of valuable crops growing on adjoining lands.
Irrigation may become necessary w^here the soil is ex-
cessively dry. It is an expensive operation, and the necessary
outlay will only be recouped in special cases.
Manuring rarely occurs, except in nurseries, because it is
too expensive compared with the increase in the returns
which it is likely to secure.
h. Time of Soicin;].
Nature sows in autumn in the case of most species growing
in temperate Europe, in some cases in summer, and in others
in winter or spring ; hence no absolute guide is given as to
the best time for sowing. Of the naturally sown seed a large
portion, while lying over winter, is eaten by animals, or
perishes through adverse influences of the weather, so that
only a small portion actually germinates in spring. In
artificial sowing the seed must be carefulh' husbanded, hence
it should be done at the most favourable season for germi-
nation, namely, wdien the soil is sufficiently moist and wheu
sufficient heat is available. The best time for sowing in
temperate Europe is during April and May, according to the
local climate.
154 ARTIFICIAL FORMATION OF WOODS.
The above rule is subject to exceptions, because some seeds
will keep in good condition only for a very short period, or
their preservation involves much trouble and expense. The
seed of the elm ripens, on an average, at the end of May or
in the early part of June, and loses its germinating power
very rapidly ; hence it should be sown at once. Birch seed
also should be sown as soon as it ripens, about the beginning
of August. The seed of silver fir ripens in autumn, and, as
it does not keep well, it should be sown at once, and not kept
till spring. Many foresters prefer sowing heavy seeds, like
those of oak, beech and sweet chestnut, in autumn, because
they are bulky and it is expensive to keep them in good
condition over winter. At the same time these heavy seeds
are much exposed to attacks by animals during winter, and
as autumnal sowings germinate early in spring the seedlings
are exposed to late frosts ; hence, sowing them in autumn may
be of doubtful expediency.
In some cases autumn sowings are indicated in localities
which are not accessible until late in spring, such as high
altitudes where snow does not disappear before June. Again,
alder seed is frequently sown in winter, immediately after
harvesting, as it is difficult to keep until spring.
To sum up, it maybe said that in' temperate Europe spring
sowing should be the rule, but that certain species and certain
local conditions demand exceptional treatment.
In other parts of the world, under different climatic con-
ditions, the best time for sowing also varies according to
circumstances. In the Indian plains and low hills the
general rule is to sow at the commencement of the summer
rains, because the seeds will then be assured of a sufticient
supply of moisture, and the seedlings will have time to
establish themselves thoroughly in the ground, before the
next dry season comes round. Sowings on irrigated lands
can be made at other seasons. The seed of some Indian
species does not keep, and indeed the seed of Sal {Sliorm
robusta) often germinates before it falls, and must therefore
DIRECT SOWING. 155
be sown as soon as it ripens. In those regions of the
Himalayas, where snow may lie until late in the spring, both
autumn and sj)ring sowings are made, there being perhaps no
decided balance in favour of the one or the other season.
r. Coverinfi Vie Seed.
The objects of covering the seed are chiefly the following : —
(1.) To protect it against sudden changes of moisture and
temperature.
(2.) To protect it against being eaten by animals, especially
birds, or being carried away by wind or water.
In natural woods large quantities of seed fall to the ground ;
some of it is carried by rain water through the vegetable
covering down to the mineral soil, thus finding conditions
favourable for germination. In artificial sowings the
necessary protection is afforded by covering it with earth
to a certain depth.
The thickness of the covering is of considerable import-
ance ; if too thin, the seed is exposed to attacks by animals,
is liable to dry up or to be injured by frost ; if too thick,
germination is retarded, the seedlings have great difficulty
in pushing through the covering, and germination may
altogether fail for want of sufficient air. The actual thick-
ness depends on the general condition of the seed bed and
the species. It must be thicker in the case of loose or
dry soil, and thinner in firm or wet soil.
The seed of different species requires a different covering.
On the whole, large seeds, such as acorns and chestnuts,
require the thickest covering ; considerably less, the seeds of
beech, maple, hornbeam, silver fir ; less again, those of alder,
ash, Scotch pine, spruce, and larch ; least, those of elm and
birch.
According to experiments made by Baur* on loamy sand
* Late Professor of Forestry at the University of Munich.
156 ARTIFICIAL FORMATION OF WOODS.
the best results were obtained with coverings of llie following
tliickiiess : —
redunciUate oak .... 1-50 inclies.
Beech -75 .,
Sycamore and silver fir . . . 'GO „
Scotch pine and spruce . . . ';jO ,,
Common alder . . . . "40 „
Larch . . . . . '35 ,,
Ehu -12 „
The seed can be covered in various ways, by ploughing
(in the case of acorns), harrowing, raking, light hoeing, or by
scattering fine earth over it. Some small seeds, such as that
of Ficus elastica, need not be covered at all.
<1. Sproutinfi nf the. Seal.
During germination the rootlet is first developed, and then
the stem ; as soon as the latter breaks through the surface of
the soil, the seed is said to sprout. A few European species,
such as oak, sweet chestnut and hazel, leave their cotyledons
below the surface, but the majorit}' bring them above ground.
The interval of time between the sowing and sprouting
depends on the species, the age of the seed, and the conditions
of germination.
S})ccic>i. — Good seed sown in spring, under average con-
ditions, may be expected to sprout after a lapse of time
ranging from a week up to two and even three years. The
following data may be taken as illustrations : —
Poplars and willows . . after about 1 — '2 weeks.
Elm and birch 2 — 3
Scotch pine, black pine,
Weymouth pine, and larch ,. ,, 3 — 4
Spruce, silver fir ,, 3 — 5
Oak, beech, maple, and alder . .. ,. 4 — (>
Ash, lime, hornbeam, and Cembran pine generally after
one year, yew after one and often two and even three years.
DIRECT SOWING : BROADCAST. 157
Age of Seed. — Fresh seed germinates always quicker than
old, the latter sometimes not mitil the second year.
The time of sprouting dej^ends much on the conditions to
which the seed is subject ; a heavy covering retards germina-
tion ; warm soil and sufficient moisture produce quicker
sprouting than cold soil or drought.
Seeds are sometimes specially treated with the object of ac-
celerating the sprouting. Amongst the various methods which
have been recommended the following may be mentioned :
soaking in water, ranging from an hour to a week ; treatment
with lime water or highly diluted hydrochloric acid ; steaming ;
soaking in liquid manure. Apart from the first mentioned,
great care is required in applying the various treatments, else
the seeds may be injured. In the case of large seeds, like
those of teak, collecting them in a heap and keeping them
continuously moist may considerably accelerate germination.
Seeds which germinate only in the second year may be
bedded in sand in a ditch or pit, and sown in the second
spring.
B. Methods of Sowing.
In the course of time a great variety of methods of sowing
have been elaborated. It would be beyond the scope of this
book to describe them all in detail ; moreover they can only
be fully understood by studying them in the field. Hence,
only the more important methods will here be mentioned.
Sowings may be divided into : —
(1.) Broadcast sowing.
(2.) Partial sowing.
1. Broadcast Soicin>oiciii(i iu fiirroics ;
it is specially employed in the case of heavy seeds, which are
sown in the furrow and covered, either by drawing a second
furrow or with the rake or hoe. It admits of a further
reduction of expenditure as compared with regular strips.
//. Soiriny in Patrlu'><.
The seed beds consist of round, oblong, square or rectan-
gular patches of limited extent, scattered as evenly as prac-
ticable over the area. The extent of the patches varies
according to circumstances ; they may l)e of any size, but are
mostly from 1 to 3 feet square, or they assume the shape of
DIRECT SOWING : IN PATCHES.
165
inteiTupted strips, which are from 1 to 2 feet hroacl and
perhaps from 3 to 10 feet long. The distance hetween the
patches depends on the same considerations as in the case
of strip sowing.
The method is cheaper than the regular strip sowing ; it
enables the forester,
on uneven or rock}'
soil, to select the most
suitable spots for the
seed beds, a matter of
greater moment than
a mathematically even
distribution of the
patches.
The working of the
soil is l)est done with the
hoe ; on stony soil hoes
with narrow and very
strong blades are used,
or even the pick ma}'
be required. The seed
is covered with the
rake or by hand, or by
scattering earth over it.
The method is well
adapted for rocky soils,
and localities which
still contain the stumps
and roots of a former
crop of trees. It is
less to be recommended
for wet soil, as the water is likely to collect on the seedbeds ;
this would, on the other hand, be an advantage in localities
with a scanty rainfall. Where a strong growth of tall weeds
is apprehended, the patches must be of sufficient size to
prevent the plants from being overgrown.
Fig. 37.
a, a. Sown patches.
Ififi
AKTIFiriAL FORMATION OF WOODS.
'■. Sorri/ii/ ill Holes, or liibhlimj.
Sowing ill holes means sowing in patches of such Hniited
extent that only a few seeds are sown in each. The soil may
he worked with an ordinary hoe of small size, with a spade or
with specially constructed modifications of tlie latter, such as
the siim-cd spath- (Fig. 38). On stony soil the pick may he
used. The spiral spade is forced into the ground and then
turned round, so that a seed hole filled with loose soil is
produced. The seed is either pressed
into the soil to the required depth,
or placed on the surface and covered
hy hand with a sufficient quantity of
fine earth, which is gently pressed
down.
If the seed hed is still smaller and
consists simply of a narrow hole sufficient
to take one or two seeds, which are
sown without any preparation of the
fsoil, the method is called " ilih]>}iit;i."
The minute holes are made with a peg,
dihbling mallet, dibbling spade, or any
other suitable tool. The instrument is
inserted into the ground to the required
depth, withdrawn, the seed placed in
the opening thus produced, and the latter closed again
either by one or more blows with the instrument, or by
pressure with the foot. In some cases the operation may
l)e done without any instrument at all, by removing a
small (luantity of the surface soil with the foot, inserting
the seed, replacing the previously removed eaith. and pressing
it down.
The luelhod is only admissible on soils wliicli are not
subject to a heavy growth of weeds, which would probably
smother the young seedlings ; moderately sized stones or
gravel do not interfere with the adoption of the method.
Fijr. 3S.
DIRECT SOWING I IN TRENCHES. 167
(L So/ring in 7Vmrhes, or Pits.
In the methods so far described the seed bed is situated
on the same level as the surrounding ground. In the case of
trench and pit sowing it is placed below the ordinary surface
of the ground, at the bottom of a trench or pit, in which
water may collect. The general arrangement of the trenches
or pits is the same as in the case of strips or patches
respectively. Trenches must be level, to prevent their be-
coming water channels. For the same reason they should
be interrupted here and there.
The width of the trenches will, as a rule, not exceed two
feet at the bottom; the depth depends on the requisite
Fi-. 3y.
a. Soil taken out of the trench. b. Trench filled with water.
c. Seed-bed.
amount of water. The distance between the ditches or pits
depends on the same considerations as in strip and patch
sowings.
The trenches may be made with the spade, hoe or pick,
or partly with the plough and the rest with those tools. The
surface soil is kept apart and placed at the bottom of the
trench to serve as a seed bed, or better still, it is at once
placed into the previously made trench.
The seed is sown by hand and covered either by hand or
with a rake. Where the trenches can be filled artificially
with water, or irrigated, the seed is frequently sown on the
upper edge of the ditch (Fig. 39), so that it receives sufficient
moisture by percolation, without being destroyed by an excess
of water. Where irrigation water is not available, and the
168 ARTIFICIAL FORMATION OF WOODS.
rainfcill varial)le, seed may be sown both at tlie bottom of
the ditch and along one of the upper edges. In the case of a
scant}- rainfall the former will succeed, and in case of a wet
3'ear, the latter.
The method is indicated in dvy hot localities, and where
irrigation is practicable. As it is expensive, it should be
adopted only in cases where a cheaper method is not likely to
yield satisfactory results. The pit method is cheaper than
trench sowing, but it frequently yields less favourable results,
and is not applicable where irrigation is contemplated.
e. Sotriiifi on Kiihjes and MouikIs.
This method is the reverse of the one described under d.
It is advisable in the case of wet or heavy soil, the object
being to raise the seed bed above the water level, and to expose
the soil to a more complete action of the air. Mounds are
interrupted ridges, just as patches are interrupted strips. The
ridges or mounds are formed, either by drawing together the
surface soil, or better by excavations. In the case of ridges
the ditches run along either one or both sides ; in the case of
mounds the earth may be taken from an excavation on one
side, or from a trench surrounding the mound.
Where a moderate elevation suffices, parallel ditches may
be dug, and the excavated earth spread evenly over the inter-
mediate spaces, thus forming elevated platforms on wliicli
the seed is sown. See Fig. 19 on page 187.
The seed should be sown densely and not too early in
spring, so as to allow a portion of the moisture to evaporate
before sowing. The tools used are the same as for trench or
pit sowings.
The method is expensive and only indicated in exceplioiuilly
unfavourable localities.
/. ('onthindHdiif'.
It happens not unfre(|U('ntly. that two or more of the
different methods ar(; combined in tlio same locality. Such
fonibiiiations are indicated when the character of the locality
PLANTING 169
changes from place to place ; if, for instance, dry spots alter-
nate with swampy ground, the former may be sown on the
natural level or in ditches, while the latter necessitates sowing
on ridges. Where free soil alternates with stony or rocky
parts, the former may be sown in strips, and the latter in
patches or holes, etc.
Section II. — Planting.
By the term planting is understood in sylviculture the
method of forming a wood by means of plants which have
been raised elsewhere. The success of the operation depends,
as in direct sowing, on many matters, which hold good, more
or less, for the different ways in which the actual planting is
carried out. The business of raising the plants is in itself one
of great importance. Planting with slips, layers, etc., again, is
so different in many ways from the planting of seedlings, that
it will be considered separately. Hence, the subject now
under consideration may be divided into the following four
sub-sections : —
A. Conditions of success.
B. Piaising plants.
C. Methods of planting.
D. Planting of slips, layers, and suckers.
A. Conditions of Success.
This subject may be dealt with under the following
headings : —
1. Choice of species.
2. Different kinds of plants.
3. Quality of plants.
4. Age and size of plants.
5. Season for planting.
6. Density of planting.
7. Distribution of plants over the area.
8. Number of plants per unit of area.
170 AHTIFICIAL FOKMATION oF WOODS.
!). Liftiiif]; plants.
10. I'liining.
11. Protection in transit.
1-J. Preparation of the soil.
1. Clinicc of Sjx'iies.
Reference is invited to what has been said in chapter I.,
section I. of Part II. In addition it remains to be men-
tioned, that planting is admissible in the case of all species,
and that it is specially adapted for those which are tender
during earl}- youth, and which cannot receive sufficient atten-
tion and protection in direct sowings on a large scale ; also to
species the seed of which is expensive, or exposed to dangers
from animals,
2. Dift'i'i-rnt Kinds of Planta.
The plants used in sylviculture are of many kinds, according
to external form, origin, age, etc. No general classification is
possible, since the various groups overlap each other. For
practical purposes the following divisions will prove useful : —
A distinction must, in the tirst place, be made between
plants which have sprung directly from seed, and those which
formed part of an already existing individual ; hence the
division into : —
(1.) Seedling plants.
(2.) Suckers, layers, or cuttings.
All woody plants can be successfully raised from seed, but
only certain species from suckers, layers, or cuttings.
Hooted plmits are distinguished from plants irithoitt mots.
Seedlings, suckers, root cuttings, and layers when they have
become independent individuals, are rooted ; cuttings taken
from the stem or branches are without roots at starting, but
they may i)econie rooted by placing them in a nursery before
putting them out into the forest.
Coniph'tc or htfoiiiplvtc jilanis ; tiie lormer have their roots,
PLAXTIXn: QUALITY OF PLANTS. 171
stem and branches entire, while in the case of the latter parts
of the plants may have been pruned away.
S('cdUu[is or transplants. — The former are plants which are
transferred direct from the seed bed to the forest ; the latter
those which were previously pricked out, once or several
times, in the nursery.
Plants n-ith balls, or lumps of earth in which the roots are
embedded, or plants a-'ithout balls.
Plants may be classified, according to size, as small, middle
sized, and large plants, but the limits of each class differ
according to the kind of plant, as well as to locality an 1
custom.
8. Qnalitu of Plants.
The success of planting operations is governed by the
quality of the plants which are used, just as the success of
direct sowings depends on the quality of the seed. Hence,
only healthy, vigorous plants should be used, which are
likely to bear well the interruption of growth involved in
the transfer from one locality to another, under circumstances
admitting only of a limited amount of attention being paid to
each plant.
The vigour, or growing power, of a plant is indicated by a
normal shape and a healthy appearance. The development
of each part must be in due* proportion to the rest ; the plant
should be neither tall nor thin, nor too short and stout; nor
should the stem be crooked, especially in the case of coni-
ferous plants ; the root system should be ample, with a fully
developed system of rootlets ; the crown should have a healthy
green appearance, and possess numerous well developed buds.
These are the general characteristics of good healthy plants.
At the same time they are subject to some modifications as
regards species, age, and the locality which it is proposed to
plant up. More especially some caution is necessary in trans-
ferring plants from a rich to a poor soil ; from a cool northern
aspect to a hot southern one ; from a low to a high situation ;
from a sheltered to an open spot, etc. ; in other words, what
172 A1{TIF1('IAL FOinrAIIoN OF \V(>(>I»S.
is a good pliiiit for one locality, may l)e only an inditVcifnt
ono for a locality of a different character.
A further niodilication may be introduced o\vin,\' to the
cost of raising the plants and of planting them out. Plants
with naturally extensive root systems either cost much to
plant out, or the roots must be crowded together in an un-
natural position ; from this point of view a compact root
system may be considered as an essential point in a good
plant, though it may not be altogether in proportion to the
stem and crown.
4. A/ Plants.
Plants aged from a few weeks up to ton and more years
may be planted out ; in fact the age is only limited by the
size and weight of the trees, and the mechanical appliances
available for the transfer. In sylviculture only young plants
under ten years of age need be considered. It may be said,
as a general rule, that young plants are best, because the
operation of planting is cheaper, the plants survive more
easily the interruption of growth involved in the change,
and they adapt themselves more readily to new conditions.
The best age for planting out depends on the species and
locality. Quick growing species can be planted out earlier
than slow growing ones. Some tropical species grow so
quickly that the most suitable age for transplanting may
be only a few weeks. In the temperate climate of Europe
yearlings, with the exception of Scotch pine and oak. are
only exceptionally planted out, as they are still too soft and
have incomplete root systems. In the great majority of
cases plants from two to four years old are used, while older
plants are indicated only in the case of a few species, or
where trees of some height are rcMjuired, as in pastures, in
frost localities, for lilling up blanks in already fornied plan-
tations, to become the overwood in coppice with standards,
to enable one species to hold its own against another of
quicker growth, for avenues, etc.
SEASON FOR PLANTING. 173
5. S<'aso)i for Plantinq.
The planting out is, after all, a violent operation, and is
generally accompanied by more or less injury to the root
system, with a temporary interruption of the growth. These
disadvantages can, by special care, be reduced to a minimum,
so that they affect the further development of the plant only
to a limited extent. As long as the root system is completely
embedded in a ball of earth, transplanting can be done at any
time of the year, provided the soil is in a fit condition (neither
frozen, nor too wet or dry). Again, plants, the roots of which
are not embedded in a ball of earth, can similarly be trans-
planted with success, provided the operation is performed
with care ; but as this involves extra expense, it is difficult to
ensure success in the case of large operations ; hence, for
sylvicultural planting, the most favourable season should
always be chosen.
The most favourable season diiiers according to the character
of the locality. In temperate Europe summer should be
avoided, because at that time the plant is in full assimilating
activity and most sensitive to a change of conditions, espcially
to drought. There remains then the period from autumn to
spring. Planting may be done at any time throughout that
period, provided the weather be sufficiently favourable; at the
same time mid-winter is generally the least favourable part of
this period, as frost may be expected, so that practically the
choice lies between autumn and spring. Each of these two
seasons has its advantages and drawbacks, and the question,
whether the one or other is more favourable, has been
much debated.
In the case of autumn planting any rootlets, which have
been injured during the operation, may have been replaced by
the ensuing spring, and the loosened earth settles down again
during winter. On the other hand, the plants are likely to
suffer from severe frost in their new home, or they may be
lifted by alternate frost and thaw, or loosened by the action of
174 ARTIFICIAL FORMATION OF WOODS.
wind. Autiiinn plantin}:; is preferiiMe in the case of localities
which are not accessible until late in spring, or of sj^ecies
which start early in spring.
Spring planting has the advantages that the period of severe
frost is past, and that vegetation begins shortly after planting.
On the whole it is preferable to autumn planting in the
case of most conifers, provided the work can be com[)leted
before vegetation begins. In many cases, especially when the
operations are conducted on a large scale, l)oth spring and
autumn planting have to be done.
Over the greater part of India the most favourable season
of the year is the commencement of the summer rains ; the
plants receive sufficient moisture, and they have the whole
growing season before them to settle down in their new home
and to get strong before the next dry season comes round.
Land which can be irrigated may be planted at any season,
provided the soil is not frozen.
Ij. l)eiisiti/ of Plantiiui.
The general principles which govern the density of direct
sowing apply also here ; that is to say, the cover overhead
Klif)uld ])e estal)lished within a period of from 5 to 10 years.
As plants come on more regularly than seedlings grown on
the spot, a smaller number per acre suffices, than that
required in the case of sowing. For the rest the planting
distance depends on :^-
(a.) The locality, in so far as it iniiuences the percentage
of failures and the vigour of the plants,
(b.) The species, especially its degree of hardiness and
rate of height growth in early youth. Quick growing
species can be planted farther apart than slow growing
species. Oak aiid Scotch pine must be planted dense,
on account of their tendency to branch.
(c.) The age and size of the plants; young and small plants
must be planted closer than old and large ones.
DISTRIBUTION OF PLANTS. 175
(d.) The objects of the plantmg, whether timber or fire-
wood is to be produced ; whether pieces of large
diameter or long boles are the objects of manage-
ment ; whether the wood is to serve as a protection
against landslips, erosion, avalanches, hot or cold
winds, etc.
(e.) The state of the market ; where small produce is
saleable at remunerative rates, dense planting is
indicated ; under the opposite conditions wider planting
is more profitable.
7. Distrihiitinu of Plants over the Area.
The distribution of the plants over the area to be stocked
can be either irregular or regular. The former is done by
eye measure, that is to say, after the average distance between
the plants has been fixed, the planting spots are selected by
eye. This system requires practice.
Kegular distribution is done according to geometrical
figures, the more usual of which are the following : —
(1.) The equilateral triangle, where the planting spots are
at the three coiners of the trinagle (Fig. 40).
(2.) The square, four plants being placed at the four
corners of the square (Fig. 41),
(3.) Equidistant lines or rows, in which case the plants
stand at shorter intervals in the lines than the distance
between the lines ; the plants may be said to occupy
the corners of rectangles (Fig. 42).
(4.) The quincunx form, a modification of the square form,
as will be seen on reference to Fig. 43.
A regular distribution of the plants has the following
advantages over an irregular one : —
(i.) An equal growing space is allotted to each plant,
(ii.) The plants are subsequently easier to find and
protected against being overgrown ; failures are easier
ascertained.
176
AHTIFKIAI, FOiaiATIoN OT WOODS.
(► {
T
1
t 1 •
II
» 1
i 1
Fi-. 40.
Fijr. 41.
• * < ' ♦ • • •
< ► ( > ( ► ( t • > « .
< ► ( ► < ► ( » ( > , .
> i i i i 4 1
( I 1 ► • • < I
o o o o
i t — I — • — ; — i * — I — < ► — I — ( >
o o O o
< t — ; — • — ; — < > — I — i > — \ — < I
<► 1 ( H \ i i \ < ► \ ( i
I I I I
Q O O Q
<» • it • #
Fiff. 42.
Fi-. 43.
(iii.) Tlie area l)et^Yeell the iilaiils can he more iullv utihtsed ;
grass cutting can be allowed at an earlier stage : field
crops uia\- be grown between the lines ; cattle grazing,
where unavoidable, causes less damage, esiiecially if
the plaiits are arranged in lines.
(iv.) In mixed woods the several species can he more
evenly mixed.
DISTRIBUTION OF PLANTS. 177
(v.) Early thinnings are considerably facilitated.
(vi.) The woods can be more easily protected against
damage, especially by injm-ioiis insects, or fire.
(vii.) It is claimed that regular plantings are cheaper to
execute, because the work of distributing and putting
in the plants proceeds in a more systematic manner.
Whether this advantage is realised or not, depends on
the skill of the labourers and the supervision exercised
over the operations.
Against these advantages it must be mentioned that air
currents have more easy access to regular plantations, may
sweep away the fallen leaves or heap them together, and dry
up the soil more rapidly. This disadvantage can be met by
planting shelter belts of trees with branches down to the
ground against the prevailing wind, or, to some extent, by
arranging the planting lines at right angles to the wind
direction. It is also claimed, that irregular planting is
preferable from an aesthetic point of view.
A completely regular distribution is not practicable where
the nature of the soil changes rapidly ; for instance, where
wet swampy spots alternate with dry parts, or where rocks are
scattered over the area ; nor is it necessary on small blanks
scattered over already existing woods.
The comparative merits of the three principal forms of
regular distribution have been much discussed. The triangular
form allots to each plant the most regular growing space,
since every plant is equi-distant from its neighbours ; this
favours an even development of the trees. It admits of a
greater number of plants per acre, and produces the greatest
quantity of material ; the saplings also clear themselves more
readily of their lower branches. On the other hand, it is
more troublesome to lay out and more expensive than the
two other forms.
Line planting has the disadvantage that the cover overhead
is somewhat later established, that the saplings develop
stronger branches on two sides than in the direction of the
S. N
178
ARTIFICIAL FORMATION OF WOODS.
lines, which may be accompanied In- an eccentric shape of the
stem. On the other hand, it admits of the most complete
utiHsation of the Ki"ound between the lines, and facilitates
thinnings and the removal of the material ;• the i)lants are
also easier to find.
On the whole, these advantages and disadvantages are not
of much importance, because after the early thinnings the
three forms stand practically on the same footing. Many
foresters prefer line planting to the two other forms, because
it is easiest to carry out, and perhaps the cheapest. Others
Fig. 44.
prefer the square form, while the triangular form is perhaps
less frequently chosen.
The marking of the planting spots is done with two lines
(or chains), the so-called directhuj liitr and the planthifi line.
The latter is divided according to the planting distance, each
division point being marked in a suitable way, either by a knot,
or by drawing a coloured tape through it. On the directing
line the distance between successive rows is marked in a
similar manner. In the case of square planting the marking
is the same on both lines, but different in triangle and line
planting. In the latter each division of the directing line is
DISTRIBUTION OF PLANTS. 179
equal to the distance between the rows : in triangle planting
equal to the planting distance multiplied by •866.
The lines are of a suitable length, with a pin (or peg) at
each end ; they should be made of hemp and well tarred, to
protect them against moisture. On wet soil a thin chain is
preferable to a line, as the latter is liable to alter its length.
When a large area is to be planted, it is desii-able to sub-
divide it, in the first place, into squares or rectangles, the sides
of which correspond with the lengths of the planting and
directing lines (Fig. 44). After the corners of the squares or
rectangles have been fixed, each plot is treated separately ;
the directing line is stretched along two opposite sides of it
(say a d and h c), and the directing spots marked either by the
insertion of small pegs or by small holes, or two directing
lines may be used and left on opposite sides, until the square,
or rectangle, has been planted; then the planting line is first
stretched along a b, and successively parallel to it until d c
is reached, planting being done as indicated by the marks
on the planting line.
It remains to note that in the case of triangle planting the
planting line must be doubly divided, as the plants in every
two adjoining rows are shifted by half the planting distance ;
or the planting line must be drawn back by half the planting
distance in every alternate row.
The following semi-regular system of planting is much
followed in Great Britain : — The planters are arranged in
line at stated intervals along one edge of the area (Fig. 45,
a h). Each puts in a plant where he stands. The most
reliable planter is placed on one flank at a, and he now
advances a space equal to the fixed planting distance in the
direction of a previously erected mark (flag), puts in a second
plant, advances again the planting distance, puts in a third
plant, and so on, until he reaches the opposite edge of the
area. As soon as the flanking man has advanced twice
the planting distance, the next planter advances one
planting distance, keeping at the original distance from the
N 2
isn
AKTIFiriAT- FORM.\TI().\- OF WOODS.
first mail's line, and puts in a plant. "When the flankinfjj man
proceeds to his fourth planting spot, his neif^dibour proceeds
to his tliird, while the third man advances: and so on. until
^
®
®
A
®
• •
//. Orijjiiiiil po.-itidu of plunieis. v, d. I'osition when the whole oohiiiiii is ii
on. O Fhiukinj;: man, who gives the direction.
the whole column is in motion, forming' a slaiitin.i;- line (r d),
each man taking his direction from his neighbour, who is
always one planting distance ahead of him. "When the last
niiui has reached the oi)posite end of the area, the whole
NUMBER OF PLANTS. 181
column wheels round and works back again, the flanking man
taking his direction from the last row of plants.
The method is exceedingly simple, and yields a degree of
regularity sufficient for most purposes, provided the men are
well trained for the work.
8. Xtuiiher of Plants.
In the case of irregular planting the number of plants
required per acre can be roughly ascertained by dividing with
the square of the average planting distance, given in feet, into
43560 the number of square feet in an acre.
For regular plantations the following calculations apply : —
Line planting : —
Length of area ^ L
Breadth ,, = B
Distance between the rows . . . = d
,, ,, plants in the rows . = d' ;
then the number of rows = , + 1,
and the number of plants in each row = — + 1,
d
hence the total number of plants: —
N = (I; + l)x(B+l) = Ii4B + L+B .
V d / \d' J d X d d d'
Square plantin feet X r, feet = 1,223 1.210
LIFTING PLANTS.
183
9. Lifting Plants.
Plants must be lifted in the nursery with the least
possible damage, especially to the root system, and least of
all to the fine rootlets through which the nourishing sub-
stances are assimilated. These fine rootlets are generally
imbedded in small lumps of
earth, which should not be
shaken off. In the case of
yearlings the rootlets are found
on the taproot or its branches ;
on older plants they are princi-
pally found on the side roots.
The least interference with
the roots occurs, if the plants
are lifted with a ball of earth,
in which the root system is
imbedded ; this method is spe-
cially recommended for very
young or tender plants. In the
case of older plants lifting with
balls and transport become very
expensive, so that, whenever
admissible, they are lifted with-
out balls of earth.
CL Lifting Plant with Balls of
Earth. Fig. 45.
The operation is performed
with a variety of instruments, such as the circular spade,
the hoe, the conic spade and the ordinary spade, according
to the size of the desired ball.
Young plants, up to a foot in height, may be lifted with the
circular spade (Fig. 46), provided the species does not develop
a long taproot at an early age. This instrument, which was
invented by Carl Heyer about 70 years ago, consists of an iron
l,bl. AiniFlCIAL KOKMATIO.N <>r WOODS.
inverted truncated cone, wliicli has in frniit an openin*;
sufficient to admit two fingers, and l)eliind, just above its
upper edge, a small horizontal plate up to which the spade
should be inserted. One of the edges of the front opening is
sharp, the other blunt. The diameter at the lower end
ranges from 2 to 5 inches, according to the desii-ed size of
the ball ; the diameter at the upper end is from i to I
larger, thus producing the shape of an inverted truncated cone
with a circular cross section. The handle and the cross bar
or crutch at the top are best made of wood and not of iron,
because the tool is lighter and the crutch not so cold. The
crutch is firmly attached to the handle by means of three iron
bands, as seen in the illustration ; these are firmly fastened to
the spade. The best length of the crutch is about 20 inches,
and its thickness such as just to fill the hand of the labourer.
The length of the handle depends on the height of the
labourer, but it should not l>e so long as to prevent the man
from using the weight of his body in driving the spade into
the ground.
In using the spade the stem of the plant which is to be
lifted is passed through the front opening until it occupies the
centie of the spade ; then the latter is pressed down vertically
until the plate at th(i l)ack touches the surface of the soil; it is
then turned round by means of the crutch from 180 to 8G0
degrees, and lifted with ball and plant out of the ground ;
holding it then with the left hand, the ball and plant are
pushed out towards the handle with the middle finger of the
right hand, which glides along the ])lunt edge; of the front
opening; if necessary, especially wluni using a larger sized
spade, two fingers are used.
The circular spade is used of various dimensions, with a
minimum diameter of 2 inches at the small end. Spades of
more than 5 inches diameter cannot be recommended, as the
balls are either not severed at the bottom or. even if severed,
do not come out with the spade, but remain /// sifn. l^ven
small spades demand a fairly binding soil, or (dse they will
LIFTIiNG PLANTS.
185
not work satisfactorily. The height of the spade is al)out
equal to the diameter. The ball is cylindrical, the object of
the conical shape of the spade being to facilitate its removal.
The instrument works expeditiously and cheaply ; extensive
areas have been planted with it. The seedlings are obtained
by broad-cast sowing. The instrument is also very useful in
lifting plants and planting them into blanks on areas which
^^
Ficr. 47.
Fisr. 49.
had been previously sown, and where the plants have come
up irregularly.
The hoe is also used for lifting young plants with balls ; it
is inserted from one side so as to get underneath the plant,
which is then lifted up. The operation requires skill, and
even then the method is of doubtful utility, as the balls are
likely to fall to pieces. The ordinary plantinri spade (Fig. 38,
p. KU) and the Trhlt spade (Fig. 32, p. 161) are used for the
I8t; ARTIFICIAL FORMATION OF \VOOl)S.
lifting of larger plants. The operation necessitates four
insertions, and it produces an inverted pyramidal ball. The
scmi-ciiri(l(ir spade (Fig. 47) is also used for lifting larger
plants; it necessitates onlj^ two or three insertions. The
semi-conH-al spade (Fig. 48), invented by Edward Ileyer, is so
constructed that it requires only one insertion, after which it
is turned round its axis, thus separating a ball of earth of an
inverted conical shape. The instrument can be recommended.
On stony soil a heavy, specially strong spade (Fig. 49) is
sometimes used.
h. LifHiifj Plaals without Balls of Kurlh.
This is best done with the two, three or four-pronged fork
(Fig. 35, p. 161), which is inserted from one side and bent
down backward, so that the plant is gently lifted up and
gradually separated from the soil.
Another method is to insert two spades or forks from
opposite sides, in a slanting direction, so that they meet, or
nearly so, underneath the plant ; both spades are then bent
back and the plant lifted.
Sometimes hoes, ordinary oi' pronged, are used, but they
are inferior to spades or forks for lifting plants.
PuUing up plants injures the roots and should be avoided.
10. I'nininii Plants.
As a general rule plants should not be pruned unless it is
absolutely necessary. Every cut produces a wound, exposing
the plant to disease, which may ultimately render it uniit for
the purpose for which it has been grown. Research has
shown that the unhealtiiy condition of timber trees may be
due to spores of fungi entering their tissue through wounds
received at a very early age.
Where woods are grown for fuel, or treated under a short
rotation, tlie above consideration is of comparatively small
importance ; in the case of timber jjlantations, however,
PRUNING PLANTS. 187
which require long periods of time to mature, the forester will
do well to pause before he proceeds to prune his plants.
Healthy plants of moderate size can be produced at such a
low cost, that it is far preferable to throw away badly-shaped
plants than to prune them and risk the introduction of
disease. In the case, therefore, of small and moderate-sized
plants pruning should be avoided. Such plants should be so
grown that a compact root system may be produced which
does not require pruning.
Where large plants are used, pruning may be necessary ; its
execution depends on a variety of circumstances, of which the
following may be mentioned : —
a. Shape and Condition of Plants.
In the ease of plants of a normal shape, especially if the
root system and crown are in proper proportion, pruning is
not necessary. In the reverse case, either the root system or
the crown and even the stem may be reduced in extent ; of
two leaders one may be removed, abnormally strong side
branches shortened, inconveniently long tap or side roots
reduced. The pruning of one part may necessitate the
pruning of the other, so as to establish a due proportion
between them ; if, for instance, the root system has been
pruned but not the crown, portions of the latter may not
receive sufficient nourishment and dry up. Originally normal
plants frequently require pruning, because the root system has
been injured in lifting them.
t). Species.
There is a great difference in the treatment of plants of
different species ; some stand pruning better than others, both
as regards the replacement of the pruned parts and the extent
to which they are exposed to disease.
On the whole, conifers stand pruning badly. Larch is
perhaps an exception, also deodar and Pinus longifoUa, though
they cannot be pruned to the same extent as broad-leaved
188 AHTIFlflAL FORMATION OF WOODS.
species. Tlie latter recover luucli (juicker, especially species
with a strong reproductive power after injury, such as willow,
poplar, oak, hornbeam, elm, alder. Beech and birch, on the
other hand, are less vigorous in this respect. Teak stands
much pruning of the crown, but less of the root system.
c. Lonilili/.
I'nder favourable conditions of soil and climate pruning is
less injurious than in the reverse case. On fertile fresh soil
a comparatively small root system suffices to fulfil the necessary
work of assimilation, and fresh organs are formed in a short
time ; on dry poor soil pruning of the roots must be much
more restricted.
il. Mdiiinr of Viuninij.
In all cases a clean cut should l)e made ; it should be some-
what slanting and not at right angles to the branch or root.
Where a whole branch is taken off, the cut should be Husli
with the stem to insure quick healing by occlusion ; if it is
only shortened, the cut should be made just above a strong
bud.
The operation may be performed with a pruning knife,
pruning scissors, shears, or a light hatchet ; in the latter case
the plant should be placed on a firm support during the
operation, so as to injure the remaining wood and bark as
little as possible.
11. Protection of Pldiita in Traitsit.
During transit plants must be protected against drying u[t
and frost, and this refers more particularly to the root system;
a few minutes of exposure often suffices to kill the liner roots.
The method of protection depends on the kind of plants, the
time during which the plants are in transit, the species, and
tlie climate to which they are exposed ; the drier the latter,
the more carefully must the plants hv. protected.
PROTECTION OF PLANTS IN TRANSIT. 189
Ball plants possess already a good protection in the lump
of earth in which the roots are imbedded. For transport
occupying not more than one day the balls should be packed
close together to prevent their drying up and the earth from
l)eing shaken off. Only in rare cases are such plants carried
over long distances, the cost being too great.
Plants without a ball of earth should be at once protected.
This is best done by dipping the roots immediately after lifting
into soft mud, which forms a thin layer over them ; the plants
should then be tied together in bundles of convenient size.
For transport over short distances, which occupies not more
than one day, the bundles should be placed in baskets, wheel-
barrows, carts or waggons, according to circumstances, the
roots being surrounded by, or imbedded in, moss, grass, or
earth. If the weather is dry and the sun shining, some cover
may also be provided, to prevent the drying up of the foliage.
The moss or grass used to cover them should be moistened,
and this process may be repeated from time to time during
transit.
If the transport extends over several days, further precau-
tions are necessary. The small bundles are, in that case,
bound together into large packages, by arranging the plants
so that the roots are all on one end, well wrapped in wet moss,
grass, &c., and then secured by withes. The whole package
is covered with matting. In the case of small or middle-sized
plants two layers are packed together with the roots in the
centre and the crowns outwards on both sides. Plants packed
in this manner keep fresh for a week, provided they are so
packed that no heating takes place.
On arrival at their destination the plants should be at once
unpacked, and either planted out, or heeled in (bedded in
earth) until they can be planted. The imbedding is best done
by arranging the small bundles in trenches and covering the
roots and part of the stem with moist soil. If necessary,
shelter against the sun or dry winds may also be provided,
and the plants may be watered.
I '.to AirriFlCIAI, FOiniATlON OF WOODS.
12. I'njiarKtioii of tlir Snil.
Only ill very rare cases does the soil require complete
workiiif,' before planting, and in such cases it is done by one
of the methods indicated for direct sowing. As a general rule
planting requires only working at the spots where the plants
are inserted into the ground, or none at all. In sylvicultural
operations conducted on a large scale the worked area of a
planting spot ranges upwards from a few square inches, and
rarely exceeds 2 or 3 square feet. The actual method of
working the soil depends on the methods of planting ; hence
it will be described when dealing with the latter.
B. Raising Plants.
Plants can be procured either by purchase or home produc-
tion ; in the latter case they can be taken from existing woods,
or raised in temporary or permanent nurseries. Although in
the majority of cases plants are purchased or produced in
home nurseries, the third method may in certain cases be
admissible, hence the subject will be divided as follows : —
(1.) Purchase of plants.
(2.) Plants taken from existing woods.
(3.) liaising plants in nurseries.
1. Purchase of Pl<()its.
In former times the necessary plants were, as a general rule,
grown at home, and this is still the case in many countries.
In Great Britain, and latterly also on the Continent, a highly
developed industry of raising plants for sale has been estab-
lished, and in the former country by far the majority of plants
are now-a-days purchased from nurserymen. This system is
very convenient, since the planting operations are not inter-
fered with by want of tlie necessary planting material. Pail-
way communication, also, is now so extended and rapid that
most imi)ortHnt s[)ecies of forest plants can be sent to any
PURCHASE OF PLANTS. 191
part of the country without serious risk to their health and
vigour. The art of raising strong hardy plants has heen so
fully developed hy nurserymen, that almost any description
of plants is procurable at short notice.
Under these circumstances the purchase of plants is quite
justified in Great Britain and in a few other countries, provided
the forester takes care that he receives only good healthy
plants of the description indicated on page 171. He must,
more especially, see that he receives plants with a properly
developed root system — that is to say, one which is full and
compact, but at the same time of a natural shape. It has of
late years become the practice to lay down the seedlings, when
they are pricked out, into shallow trenches, involving the
bending over of the root system to one side ; the result is a
bushy root system altogether lop-sided. If such plants are
put out into the forest, they take years to recover a normal,
healthy shape of the root system, and until this takes place
they have only a limited hold on the ground, and are liable
to be blown over by strong winds. This drawback is often
maintained up to middle age, if not longer. Unless
nurserymen give up that vicious practice, they must be
prepared to see landed proprietors revert to the system of
home nurseries.
In selecting plants care should be taken that they are suited
to the locality where they are to be planted. For fertile locali-
ties at low elevations well grown tall plants are desirable ; for
poor soil, especially at high elevations, short sturdy plants are
preferable. It is generally considered best, if no great diffe-
rences exist between the soil and climate of the nurser}^ and
of the locality where the plants are to be put out.
2. Plants taken from existing Woods.
Where operations are conducted on a small scale, and
nursery plants are not available, the planting material may
be obtained from existing young woods, such as natural
]'M AllTIl'K'IAL FORMATION OF WOODS.
reji;enerations or sowings. In such cases the plants are
taken from the parts which are too thickly stocked, and
consequently they are g(!nerally indifferently developed ; they
are frequently slow in coniiiiL,' on after transplantin;^^ and
rarely yield <^ood results.
;i. lulis'in;! Phiiits in XiirHcrics.
Where plantings are conducted regularly on a large scale,
plants may he raised in home nurseries; and even if the plants
are purchased from nurserymen, it is desirable to have an
auxiliary nursery at home ; hence it is necessary to describe
here, in outline, the establishment and management of
nurseries.
Nurseries may be temporary or permanent ; the former are
used for a few 3'ears onl}', generally to yield the material for
the planting of a particular locality, when they are abandoned
and a new nursery laid out elsewhere ; permanent nurseries
are used for a long series of years. Each has its advantages
and disadvantages. In the case of temporary or shifting
nurseries the cost of transport and the risk of damaging the
plants during transit are smaller ; on the other hand the cost
of laying out is greater, as it recurs every two or three years,
and they do not, as a rule, yield eijually good plants. Tem-
porary nurseries can be established in localities of the same
description as those where the planting has to be done ; hence
they may be desirable where distinct zones of vegetation occur,
especially in mountainous districts, also where the plants are
to be put out with balls.
Permanent nurseries require to be manured from time to
time, but they yield better plants ; they are preferable in the
majority of cases, especially in more level districts, where
large numbers of plants are required year after year, and
where the transport is fairly easy and cheap. There is
l)ractically no ditference in the treatment of temporary and
pernuinent nurseries, except that in the latter case all
arrangenunits are of a more lastiiit/ nature.
RAISING PLANTS IN NUKSERIES. 19:3
a. Clioicp of Site.
The site should be favourable for the growth of the
particular kinds of plants which are required. If only one
species or a few of similar requirements are wanted, a site
can be chosen which agrees with their special requirements as
regards soil and situation. In the majority of cases, however,
plants of differing requirements are to be raised, and it is there-
fore best to choose a site of average conditions.
The most suitable soil is a light or sandy loam. Heavy
clay should be avoided, as it is less suitable than even a light
sandy soil. Good depth is essential, as it insures a more even
degree of moisture.
As regards situation, the site should, if possible, be in the
centre of the area where the planting has to be done ; but if
no suitable locality is there available, it is better to go to a
moderate distance in search of it. The site should be accessible
and easy of control. A gentle slope is best, or an elevated
level plain ; in either case it should not be exposed to danger
from frost, especially late spring frost, fairly sheltered, but
open to the free circulation of air. The aspect depends on
circumstances, especially latitude and elevation. In temperate
Europe the least favourable aspects are probably an eastern or
south-eastern (on account of late frosts) and a southern or
south-western (on account of the rapid evaporation of
moisture).
The site should, if possible, be so chosen, that water can be
led on to it from a spring or stream, or that at any rate
water may be found at a reasonable depth for the construction
of a well.
h. Area.
This depends on the species, the method of treatment, the
number of plants, whether they are pricked out or not, and
the age at which they are finally removed. It is clear that no
general rule can be given. By way of illustration it may be
mentioned that for raising two-year-old seedlings of Scotch
s. o
194- AltTIFU'IAL FOHMATION OF WOODS.
pine or spruce, the area of the nursery should l)e about ^ per
cent, of the area to be annually planted at 4 feet apart ; if the
two-year-old seedlings are pricked out, and remain for another
two years, the nursery should conii)i-ise at least 4 per cent of
the area to be planted annually.
Where broad leaved species are raised, such as oak or beech,
the percentage is higher. It increases very rapidly with the
age of the plants ; for instance in the case of twice pricked out
oaks, which are planted out at the age of 9 j'ears at 10 feet
apart, the area would amount to not less than 30 per cent, of
the area to be planted annually.
r. Shapr.
"Whenever a free choice is possible, the shape of the nursery
should be that of a square or rectangle, because it admits of a
regular rectangular shape being given to the seed beds witliout
waste of area.
'!, »
Larch .
=
•4()
,,
Austrian pine
.
~
-20
Broadcast sowing takes from twice to four times the quantity
of seed required for drill sowing ; hence Gayer's data for
conifers agree fairly well with those given l)y Messrs.
Howden ^: Co.
/. Fr id' in II auf.
In some cases the seedlings are taken direct from the seed
bed to the forest ; in others they are transplanted once or
several times in tlie nursery before they are finally put out.
British foresters call the former " seedling plants," and the
latter " transplants."
Seedling plants which are to go direct to the forest must be
grown roomy in the seed beds, so that they may develop
properly; plants which are to be pricked out in the nursery
may stand closer together in the seed beds.
Pricked-out plants are generally placed in rows, called
" nursery lines." The soil devoted to them must be carefully
, RAISING PLANTS IN NURSERIES. 20^5
prepared, though not perhaps quite to the same extent as that
of seed beds.
The area required for nurser}- Hues depends on the species,
the age of the seedhngs when pricked out, and the time the}''
are to remain in the nursery ; on an average it may be
estimated at 8 to 10 times the area of the seed beds, provided
the plants are one year old when pricked out, and four years
old when put out into the forest.
Seedlings should be pricked out while young. In the tropics
the proper age is sometimes only a few weeks ; in temperate
Europe generally one or two years, according to the nature of
the species and the locality.
When the object is to produce large and strong plants, or a
full and bushy root system, they may be pricked out a second
or even a third time, after an interval each time of one, two
or more years.
• Plants may be pricked out at any time, provided it is done
carefull,y, rapidly, and when the soil is fairly moist. In
temperate Europe the best time for extensive operations is
early spring. Moist weather is desirable during the operation,
else the plants may have to be watered. The lifting and
protection of the plants during transit have been dealt with
above (pages 183 and 188).
The distance between the nursery lines and between the
plants in the lines depends on the size of the plants, their
more or less rapid development, and the time which they are
to remain in the lines. Ordinary two-year-old seedlings of
Scotch pine and spruce, which are to remain for two years in
the lines, may be placed from 3 to 6 inches apart in the lines,
with a distance of 8 to 12 inches between the lines. Larch
plants must be placed somewhat further apart, while for oak
the distances are still greater.
Brown, in " The Forester," recommends the following
distances : —
One- or two-year-old seedlings of oak, ash, elm, and beech,
4 inches apart in the lines, the latter being 24 inches apart.
204
ARTIFICIAr, K(>1;M AIION OK WOODS.
Oiie-vciir-ol.l liircli siH'dlin^'s . = IC. x 2.1 iiidics.
Two-yciU--ol(l larch seedlings. = IS x :{
One- or two-year-old Scotch
pine seedlings . . . = 14 x '2 ,,
^[essrs. Howden c*c Co., Inverness, generally line out the
larch one year old and Scotch pine two years old. They place
them 8 inches apart in the lines, with 1) inches hetween every
two lines.
The pricking out can he done in a variety of ways according
to the description of plants. The more usual methods are,
either to make a separate hole for each plant with a planting
peg, a small hoe, or a garden trowel, or to open trenches,
Fi- ^:5.
into which the i)lants are placed at the proper distance
apart. In either ease the roots should he placed into a
natural position, and the soil well pressed around them.
British nurserymen, in raising plants for sylvicultural
purposes, proceed in the following manner: —
The soil, after having been brought into a suitable condition,
is thoroughly smoothed along the whole length of the conrart-
ment, then a planting line is placed on it, parallel to one side
of the compartment ; then the ground is cut away with a spade
along the line, so that a shallow trench is formed with one
side almost vertical (Fig. n;}, a). Against this side the
plants are placed at the proper distance apart, some earth
pressed around them, then the trench completely filled up,
the earth pressed down once more with the foot, and the whohi
smoothed over (Fig. 58, I/}. Tlieii the i)laiitiiig line is moved
RAISING PLANTS IN NURSERIES.
205
on to the following row and the operation repeated. The
method works very expeditiously, and it is an excellent one in
principle. It has, however, become the practice to make the
trenches so shallow, that the root system of the plants, instead
of assuming a natural position in the ground, is altogether
bent to one side. The result is that the plants develop a lop-
sided root system. It may be easier to put out such plants,
besides saving expense, but the system is certainly not favour-
able to the development and stability of the trees grown from
them. The author has observed, that in many cases trees 30
to -10 years old had not yet established a normal root system,
and that numerous trees are blown down for this very reason.
To produce really good plants, the vertical side of the trench
should not be less than 10 inches deep, so thai the roots go
down straight to that distance (see Fig. 54). The additional
expenditure is not more than about one shilling per 1,000
plants,
III. Choice between Secdlbui Phaih and Transplants.
Each of these two kinds of plants has certain advantages
and drawbacks, and it depends on the circumstances of each
particular case whether the one or other is preferable.
Seedling plants are considerably cheaper than transplants,
as the latter require a larger area, as well as labour in pricking
out and tending. On the other hand transplants are much
superior, as they have more room to develop ; especially the
root system becomes fuller, more bushy and compact.
206 ARTIFICIAL FOHMATION OF WOODS.
For plantinj]; in favourable localities seedling plants may
do as well as transplants ; in unfavourable localities the
latter are preferable ; also when specially larn;e plants are
required.
The choice also depends on tlie species. In the case of
Scotch pine and oak seedlinjj; plants give good results ; in that
of most other species transplants are to be preferred.
A plan sometimes followed consists in classifying the seedling
plants when, say, two years old. The best plants are put out
directly into the forest, the second class plants are pricked out
in the nursery, and the third class, com})rising the weak and
misshapen plants, are thrown aw'ay.
//. Ti'inliiKj Seed Beds and Nurscrij Lini's.
The seeds, as well as the young plants, require a certain
amount of tending, more especially protection against injurious
influences. The details of such tending and protecting are
given under the head of Forest Protection, In this place only
the more important measures directly connected with nursery
work will be indicated.
(1.) The seeds must be protected against birds. These may
be kept off by shooting or frightening. If this is impracticable,
small seeds may receive a coating of red lead, or the beds may
be protected by placing on them thorny brushwood, branches
of coniferous trees, grass, etc., or nets may be spread over
them, resting on supports, so as to keep them at a suitable
distance from the ground. 'J'he latter have tbe disadvantage
that they must be lifted when weeding has to be done. Wire
netting, beiil in a semicircle over tlie seed beds, is most suit-
able ; it needs little sui)[)ort and lasts many years.
Mice, moles and mole crickets often do much damage ; they
must be caught or poisoned. Mice may be caught in pots
buried in llu; i)alhways and half tilled with water ; these
animals are in tbe halul of running heedlessly along the paths,
when tliey fall inl(^ the pots.
RAISING PLANTS IN NURSERIES. 207
Earthworms do damage by dragging small seedlings into
their burrows.
Hares, rabbits, etc., must be kept out by fencing with wire
netting. Squirrels must be shot.
Amongst insects, the cockchafer larvae and the wireworms
are the most destructive in temperate Europe. In both cases
damage is difficult to prevent. Cockchafers are specially fond
of laying eggs in clearings in the forest, such as a nursery ;
and if this be repeated once or twice, it may be necessary to
change the site of the nursery. Almost the only way to meet
the damage in the case of grubs of the cockchafer and the
wireworm is to collect them, or to kill them with gas lime.
(2.) Extremes of climate make themselves felt by frost or
drought.
In the first place a considerable fall of temperature inter-
feres with the proper germination of the seeds, and it may
injure young seedlings. Such damage is prevented by cover-
ing the seed beds with moss, grass, straw, needles, or short
branches of conifers, or by erecting a temporary roof at a con-
venient height over the seed beds. Very delicate seedlings
may be raised under glass. The covering should be removed
during the day and replaced in the evening. Somewhat later
on, alternate freezing and thawing may lift the young plants
out of the ground ; this can be prevented by covering the space
between the lines with moss or sawdust, or by heaping earth
on to the plants. If, nevertheless, it should occur, the plants
must be speedily put back into the ground.
Damage by drought is prevented somewhat in the same
way as that by frost, best by shades, which are placed over-
head, or on the sunny side of the beds. If the dry weather
should last for some time, the beds may have to be watered.
This, if once commenced, must be continued until rain falls.
As watering is expensive, unless it can be done by irrigation
with water obtained from a higher point, it is only done when
absolutely necessary. Many British nurserymen never water ;
tliey prefer taking their chance. In more southern countries
2(IS
AKTIFIC'IAI. FOI'.MATION OF W()f>I)S,
waterinp; frequently l)ecomes a necessity. There, also, protec-
tion u^'ainst hot winds is frequently given by shades placed on
the side whence the wind blows.
(3.) Weeding should be done frequently and thoroughly.
It can be done by hand, or with knives, weeding forks
(Fig. 55), light two- or three-pronged hoes, the Dutch lioe
(Fig. 56), etc.*
The weeding is generally accompanied by some loosening of
the surface soil ; but apart from weeding, periodical working of
the soil between the nursery lines is highly beneficial.
(4.) If the seedlings come up too thick in the seed-beds.
Fi-,'. .55. Fig. o6.
they may be thinned out. In doing tliis, care must be taken
not to disturb the plants which are to remain ; hence the best
plan is to cut off the weakest plants close to the ground with
scissors.
C. — Methods of Planting.
The most important point in planting is to reduce
the
interruption of growth to a minimum, so that the plants may
quickly estal)lish themselves in their new home. How this
object can be realised depends on the description of the plants,
their size, and the conditions of soil iuid cliniate. To meet the
• Figs.
.1 .-Hi liave Imcii tak.'ii fnun r.iM.lcs Cc
Illus
itc'LANTlNG WITH PEG OR STAFF.
2i5
it is frequently necessary to work the soil before planting,
either entirely, or in strips or patches. This can be done
Fig. 65.
with a light plough or the hoe. In such cases the area may
be used for the raising of a field crop before planting.
Pegs of various shapes are used, such as the ordinary
planting pegs (Fig. 62), the planting
dagger (Fig. 63), Buttlar's iron (Fig. 64),
etc. The planting peg is constructed of
wood ; Fig. 63 consists of a wooden peg
with an iron coating up to the handle ;
Buttlar's tool is made entirely of iron,
the handle being covered with leather ;
it weighs about seven pounds.
When using any of these tools the
planter holds a bundle of plants in one
hand and the tool in the other ; he inserts
the tool into the ground (Fig. 65, a),
takes a plant out of the bundle, holds it
between two fingers, withdraws the tool,
inserts the plant into the hole, re-inserts
the tool in a slanting position (Fig. 65, h),
and presses earth on to the plant by push-
ing the peg towards it. The second hole
thus produced (Fig. 65, c), can be filled up by inserting the
tool a third time, or by pressing earth into it with the foot.
216
ARTIFICIAL FORMATION OF WOODS.
In these plantings the root should go down straiglit into
the hole, and not be doubled up. To facilitate the operation
of insertion, and to protect the fine roots against drying,
they are frequently dipped into soft mud as soon as they have
been lifted.
The method is cheap and of great despatch, especially if it
is not necessary to work the soil beforehand. It is specially
adapted for light sandy soil, less for stiff soil, or for a locality
%d
Fi-. G'J.
which is likely to be overrun by weeds. The plants should
not be more than two years old, or else they will have
developed too long side roots. Only seedling plants should
be thus planted.
Where deeper holes are required, or on slony soil, the
planting staff (Fig. GO) may be used. It is a muc-li heavier
tool, weighing about eleven i)ounds, and two men, or a man and
a boy, are required for the operation, one making the holes
and tlie oilier insert ing iliu i)Ianis.
PLANTING : NOTCHING.
217
r. JVo/c/ri/if/.
This method differs from planting with a peg in the shape
of the planting hole, which is that of a notch. The tools
ordinarily used are the planting hatchet (Fig. 67), the notching
spade (Fig. 68), and the ordinary spade. The hatchet is
inserted into the ground with one hand and pulled out again,
thus producing a notch, in which the plant is inserted ; the
Fig. 70. Fig. 71.
notch is closed by knocking the adjoining earth into it with
the thick end of the hatchet ; finally the soil is pressed down
with the feet.
The notching spade is wedge-shaped, and after insertion
into the ground an enlarged notch (Fig. 69) may be produced
by swaying the spade to and fro. The tool requires two
persons, one making the notches, and the other inserting the
plants, filling in, and pressing down the earth with his feet.
The common spade can be used in the same way as the
notching spade, but a much better shape is that exhibited in
218
Airni-UIAL roKMATiON OF WOODS.
Fig. 70 {a, b). It is perfectly straight, willi a sharp ^xjiiil
which easily penetrates into tlie soil. In using this spade
the notch generally has the shape shown in Fig. 70 (c)
(exaggerated). The plant, after insertion into the notch, is
securely fixed in the ground as indicated in the case of
planting with the peg (Fig. Go). This spade is no douht the
hest tool for notching which has heen constructed.
On stiff soil the holes for seedling plants may be made with
a hollow spade, like Fig. 71. It is not necessary to remove
the ball of earth from the spade by hand ; by inserting the
spade for the purpose of making a second hole, the ball of
earth taken from the previous hole is ejected at the top, and
can be used to fill up the hole afterwards. The plant is
inserted as before, and the hole is filled up and the soil
pressed down firmly by means of a peg and the feet.
^ d^__^ ^^^_j|
^
V -' /::=-
Fiir. 72.
In Great Britain notching is done in a somewhat different
way, generally with the ordinary spade, so as to i)roduce a
T-shaped or a triangular notch, mostly the former. The
spade is inserted into the ground (Fig. 72, a), and withdrawn ;
then it is a second time inserted at light angles to the first
insertion and at one end of it (Fig. 72, h) ; next the handle is
bent backwards, thus raising and opening out the edges of the
first notch (Fig. 7*2, r) ; then the plant is slipped in fiom the
MOUND PLANTING. 219
blade of the spade towards the far end of the first notch, the
spade withdrawn and the soil pressed down with the feet, so
as to cause the notches to close completely. The operation
requires two persons, a man and a boy.
The merits of ordinary notching are very much the same
as planting with a peg. As regards the British method of
notching it must be noted that the root system obtains an
altogether unnatural position, it being completely pressed to
one side (compare Fig. 53, h, on page 204). It has already
been pointed out in that place, that often many years pass
before this drawback is overcome. The system as practised
in Britain can yield satisfactory results only under a favour-
able climate and in the case of certain species. It is chiefly
employed in planting Scotch pine and larch plants two to
four years old.
3. Mound Planting.
Apart from wet and swampy localities, planting is sometimes
done on mounds, instead of in pits.
The mounds are formed either by scraping together the
ordinary soil, or by depositing a
basketful of specially prepared soil
at regular intervals. The plant is
inserted into an opening produced
in the centre of the mound, and
then the soil pressed round the
roots until the mound has been ^in- 73.
re-formed. Finally the mound is,
whenever practicable, covered with turf, to protect it against
rapid drying. For this purpose two pieces of turf are placed,
one on the shady side [a), and the other on the sunny side (h),
so that the latter overlaps the former (Fig. 73). In the absence
of tarf, stones may be placed on the mound.
The method is only suited to plants with a shallow root
system, if the mounds are to be of moderate size. It has
yielded good results on soil, such as gravel or hard clay.
:l-20 ARTIFICIAL FORMATION OF WOODS.
where the striking of tlio plants under orJuiary pliintin<^
would have heen douhtful. The expenses are higher than
in the case of pit planting, but not by very much, since the
method contemplates only small mounds.
Where mound planting is adopted against an excessive
degree of moisture in the soil, the mounds must be consider-
ably higher and larger than in the method just desscribed.
The expenditure is further increased if the planting is done on
continuous ridges, prepared as described on page 137.
D. Planting of Slips, Layers and Suckers.
Plants of these kinds are used in the case of species which
do not readily seed, or the seed of which germinates indiffer-
ently, or for the purpose of obtaining at once plants of some
size. Such methods are only auxiliary in temperate Europe,
except in the case of willows and poplars.
1. Slips.
A slip or a cutting is a rootless plant, which consists of a
piece of young green wood taken from the stem or a branch of
a rooted plant ; when inserted into the ground it develops roots
and crown. Poplars and willows are grown in this way.
Slips may retain the leading shoot or be truncated. The
former consist as a rule of stool shoots ; the latter can be
taken from stool shoots or from the branches of older trees,
their length differing from a few inches up to ten or more
feet.
In some cases slips are in the first instance placed into
nurseries until they have become rooted, but they are gener-
ally planted out at once in the forest. The insertion into the
ground can be done in various ways, such as placing the slips
ill furrows and covering llicni by drawing a second furrow
witli the plough ; or they may be placed in ditches, trendies,
l)its, or each slip simply pushed into the ground to the required
ilepth.
PLANTING SLIPS, LAYERS AND SUCKERS. 221
When entire slips are used, onl}' the lower portion is inserted
into the ground ; of truncated slips only a small part remains
above the surface. In order to insure striking and a proper
development, the ends of the slips should be cut sharply- and
smoothly in a slanting direction, and each truncated slip must
contain some buds, of which at least one, or better several,
must be above ground. It is also essential that the bark
should not be injured at the ends; hence pushing the slips
into the ground without a previous opening is only admissible
in very loose soil ; in all other cases they should be planted
with a special iron dibble.
The best time for planting slips is early spring, shortly
Fig. 74.
before the buds begin to swell, though, under favourable circum-
stances, the slips can be planted at other times, even during
the growing season. The roots formed after planting come
from the callus produced at the lower end or from the lenticels
in the bark.
In England the stools of osiers are recruited by slips, which
are mostly entire ; they are planted immediately after the
osiers have been cut, usually in December. On the Continent
truncated slips are used in preference.
2. Layers.
Layers are branches, or stool shoots, which have been bent
down and partly buried in the soil ; they develop roots at the
buried portion, and when this has taken place, they are severed
222 ARTIFICIAL FORMATION OF WOODS.
from the mother tree and represent independent plants ready
to be put out. The formation of roots may be expedited l)y
removing some of the ])ark of the layer below ^M-ound on the
side of the parent tree.
Where large numbers of layers are required, the most suit-
able plan is to produce stools wliich send out numerous shoots.
Each of these shoots is then bent back and fastened into tlie
ground, where it remains until rooted (Fig. 74). In England
lime and elm are generally propagated in this manner.
3. Siirhrrs.
The root from which the sucker has sprung is cut through,
clean and slanting, on both sides of the base of the sucker, the
latter lifted out of the ground and put out into the forest.
The method is rarely used, as disease is likely to be introduced
through the cut ends of the root.
In some cases pieces of roots are planted out, which produce
roots and shoots.
Note. — Grafting and Budding, being outside practical sylvi-
culture, will not be dealt with in this volume.
223
CHAPTER III.
NATURAL REGENERATION OF WOODS.
Natural regeneration can take place by seed, or by shoots
and suckers. Accordingly the subject divides itself naturally
into two parts. Regeneration by seed is applicable to all
species ; that by shoots and suckers applies only to broad
leaved species, since the power of reproduction of conifers by
shoots is either absent altogether, or at any rate so feeble that
it is useless for sylvicultural purposes.
Section I. — Natural Eegeneration by Seed.
By natural regeneration by seed is understood the formation
of a new wood by the natural fall of seed, which germinates and
develops into a crop of seedlings. The trees which yield the
seed are called the mother trees ; they may stand either on the
area which is to be re-stocked, or on adjoining ground.
Accordingly a distinction is made between —
(A.) Natural regeneration under shelter- woods ;
(B.) ,, ,, from adjoining woods.
A. Natural Regeneration under Shelter-woods.
The area is stocked with seed bearing trees, and the new
generation springs up under their shelter ; for some time, at
any rate, the area bears the new crop and part of the old one.
The system is that which occurs in primeval forests. When
a tree falls from old age, or other cause, and an opening is
thus formed in the cover overhead, the seeds falling from the
adjoining trees germinate and develop into seedlings ; these
grow up under the shelter of the older trees, until they in
their turn become mother and shelter trees. In this manner
221 NATIRAL HKdKNEHATION (>F WOODS.
primeval forest, if undisturbed, goes on regenerating itself for
generations. The process is a slow one, as the young crop
will only develop when sufficient light is admitted by the fall
or death of the old trees. In sylviculture it is accelerated by
the artilicial removal of a portion of the old trees, when they
have become lit for economic purposes. By degrees, modifi-
cations have been introduced, which lead to a number of
distinct methods. Of these, the following demand special
notice : —
(1.) The Scleriiiiii Si/stciii.*— The age classes are evenly, or
approximately evenly, distributed over the whole area of the
forest. Throughout its entire extent the oldest, largest, and
diseased or defective trees are year after year, or periodically,
removed, followed b}^ the springing up of new growth in small
patches or single trees.
(2.) The Group Si/steni. — The age classes are distributed over
the forest in groups of moderate extent. The oldest groups
are regenerated first, then the next oldest, and so on, until the
whole forest has been gone over. Some modifications of this
system have been introduced, which will be explained further on.
(3.) The Compartment Si/stem.*^ — The age classes are so far
separated, that each occupies a distinct portion of the area,
representing an even aged, or approximately even aged, wood.
Each wood comprises one or moie compartments, and either
the whole, or one compartment at a time, is regenerated
uniforml}' over the area, so that tlie old crop is re})laced by a
young, fairly even aged wood.
(4.) The Strip Si/strm. — This is a modification of the com-
partment system, each compartment being divided into a
number of strips. As it differs from the compartment system
in some respects, it will be dealt with separately,
* The term selection syxtnn was intiodiicoil in India ; it is perhaps not an
ideal term, since a certain amount of selection is practised in all systems; it
has been retained, as none better is at jirescnt available. The system is called
Frmrlbetrieb, or Pldnterhetrielj, in (Jcrman. and Jurdimige in French.
f Sehlfif/ireiner Jietrieh in (icruian, and mithode jmv eouprx mcrots) vex in
French.
THE COMPAETMENT SYSTEM. 225
The limits between the several systems are not alwa3's
clearly defined, as will be seen further on, but there are certain
general conditions of success which hold good for all. Amongst
these the following may be mentioned : —
(1.) The mother trees must be capable of producing good
seed in sufficient quantity.
(2.) The soil must be in such a condition that it forms a
good germinating bed.
(3.) The young seedlings must have sufficient light to grow
up, and yet, if tender, they must be protected against
external injurious influences.
(4.) The fertility of the locality must be duly preserved by
protecting the soil against the sun and air currents.
These conditions, if not naturally existing, must be produced
l)y timely and judicious interference. The measures adopted
for the purpose consist in —
(«.) Cuttings so executed that they produce the desired
conditions.
{J>.) Artificial preparation of the germinating bed, if this
should he necessary.
The several systems comply with these conditions in
varying degrees. In order to bring out the general character-
istics of the methods, it is desirable to commence with a
description of the compartment system.
1. Tite Comj)artment or Uniform System of Natural
Rer/eneration under SJielter-woods.
The regeneration occurs approximately at the same time
and uniformly over a whole wood, which, for convenience' sake,
is here called a compartment. The area treated at one time
and in a uniform way is called the regeneration area. The
new crop should be created, if possible, by one seed year over
the whole regeneration area ; this, however, succeeds only in
exceptional cases, so that, as a rule, two or even more seed
years are required to complete the regeneration. As a
consequence the regeneration process may extend over a
•226 NATrKAI. HEOENKRATION OF WOODS.
term of ;"). 10. 15, iuid sometimes even more years, resulting' in
a new croj) wliich is only approximately even aged.
The euttiii<;s are made from time to time as required, and
so tliJit the old or shelter- wood gradually makes way for, and
is replaced hy, the new crop, the process heing as uniform as
practicable over the whole regeneration area. These successive
cuttings are, for convenience' sake, generally arranged into
three groups, each of which represents a distinct stage,
namely, —
(a.) The preparatory stage.
(h.) The seeding stage.
(r.) The final stage.
Theoretically speaking, the preparatory and final stages each
comprise several cuttings, and the seeding stage only one,
but their actual number depends on the circumstances of each
case, as will be seen from the description given Ijelow.
/'. /'i/'/it/n//or// Slatjf.
There is a time in the life of every wood which is most
favourable for natural regeneration ; it occurs during the
period of maturity, but differs somewhat in accordance with
the special conditions of each wood. That time is, theoretically
speaking, the best for the process of regeneration, but other
important considerations may not always permit of this
particular period being taken advantage of. Only in rare
cases have the trees at that time reached a profitable size for
economic purposes ; hence, they must be allowed to grow on
for a series of years, and thus pass the most favourable period.
In other cases, where only small material is required, the
objects of management may demand cutting over before the
most favourable period for regeneration has been reached.
Pi very such deviation ci-eates obstacles to successful regenera-
tion. Either the trees are not in the best period of life for the
production of good seed in sufficient quantity, or the soil is
not in the best possible condition to serve as a germinating
bed. It is the object of the pnparatori/ riittiii;is to counteract
THE COMPARTMENT SYSTEM. 227
these and other drawl^acks, which require to he more fully
explained.
i. Preparation of a Suitable Seed Bed.
The soil must he hrought into a condition which ensures a
proper germination of the seed, and enahles the seedlings to
reach the mineral soil with their rootlets within a reasonable
time ; it must be suitably porous and moist. The necessary
measures to ensure this depend on the condition of the wood,
and on the nature of the locality.
In the course of a rotation crowded woods produce con-
siderable quantities of humus, which decomposes at a quicker
or slower rate according to species and other circumstances.
Where, on approaching the period of regeneration, the layer
of humus and leaves is so thick that seedlings cannot reach
the mineral soil w^ithin a few weeks after germination, it must
be reduced before regeneration is attempted. This is done by
removing some of the trees, and thus admitting the sun's rays
and a more active circulation of air, which cause an accele-
rated decomposition of the humus. The severity of the cutting
depends on the original density of the leaf canopy ; dark cover
overhead demands a heavy cutting, a thin cover a light cutting
or none at all. It also depends on the nature of the soil ;
over limestone the humus decomposes rapidly, on cold heavy
soil slowly. Again, the leaves of some trees decompose more
rapidly than those of others.
Situation and the local climate must also be considered.
Where the degree of moisture in the soil and the air is high,
decomposition proceeds at a slow rate ; such localities are
high situations, northern aspects, moist valleys, the shores of
lakes and the sea. In all such cases the preparatory cuttings
must be comparatively heavy.
On the other hand, in localities which are liable to be
overrun by a heavy crop of grass or weeds, the cuttings must
be light, or else the young seedlings will be choked.
Generally, the most suitable condition for germination has
been reached when the covering of the soil has been so far
q2
22S NATTRAL REGENERATION OF WOODS.
reduced that the mineral soil can be seen hero and there
through it, without bein^]; altof^'ether exposed ; the seedliiip;s
will then be able to establish their rootlets in the mineral soil
at an early stage, and thus escape the danger of being killed
off by a subsequent spell of dry weather. Tf. at the conclusion
of the preparatory stage, this condition h;is not been reached,
a portion of the humus and leaves or moss may have to be
removed artificially, or mixed with the mineral soil below.
In many cases the vegetable covering of the soil has been
already too much reduced by a premature interruption of the
leaf canopy, so that the most favourable condition of the seed
bed is past, the soil having becon^e hard and dry, or overrun
by grass and weeds. In such cases further cuttings would
only increase the evil, and must therefore be omitted ; a suit-
able seed bed is in that case secured by working the soil
immediately before or after the seed falls. The working of
the soil may consist merely in removing the weed growtli, or
in hoeing it up either entirely or in strips or patches, causing
it to be broken up by pigs, raking, harrowing, or even ploughing
it with a light forest plough. Generally speaking, this opera-
tion is known as " ir<>undi)ifi the. soil,'' and is considered a most
important cultural measure. At the same time it is expensive,
and should be executed only when necessary.
ii. Stukngthening ihe Shici;ieh Tiikes.
After the ground has actually become stocked with seedlings,
only a certain number of the trees, which formed the original
wood, will remain on the ground to afford shelter to the young
crop and the soil. If all the rest of the wood were removed at
one cutting, so that the above-mentioned shelter trees were
suddenly brought from a crowded into a comparatively open
position, they would probably be thrown by the first gale.
To avoid this they must be i)laced only gradually in a more
open position, so as to obtain a firmer hold of the ground.
This is done by the preparatory cuttings.
The trees which are to form the ultimate shelter-wood must
THE COMPARTMENT SYSTEM. ^29
be selected from the beginning ; they should be trees with
neither exceptionally broadnor narrow crowns, but healthy
trees with medium crowns, and these must be led over gradu-
all}' from a crowded to a more open state. It follows that,
from this ix)int of view, the preparatory cuttings are of more
importance in the case of shallow-rooted species and very
dense woods, than under opjjosite conditions.
iii. Sti.mli.ai iN(i thii I'roductiox uv Sked.
In some cases placing the trees in a more open position has
a beneficial effect upon the production of seed, but this cannot
be always relied on, as frequently such a measure is followed
by increased production of wood instead of seed.
iv. DlsTRIBUTIO.V OF THE YlELl).
If forest trees were in the habit of producing seed regularly
every year, arrangements might be made to place annually
a suitable area into the seeding stage, and thus distribute the
cuttings equally over successive years. As, however, most
forest trees produce abundant seed only after irregular inter-
vals, it is necessary to take full advantage of every such
opportunity and then to bring as large an area as possible
into the seeding stage. If no preparatory cuttings had been
made, such a treatment would lead to an excessive yield in
every seed year, and little or no yield in other years. Hence
preparatory cuttings fulfil the further duty of assisting in the
proper distribution of the yield.
V. NUMBEIl .\.ND C'HAU.VlTEK OF CuTTINGS.
Whether the preparatory stage should comprise one or
several cuttings cannot be determined beforehand; it depends
on the circumstances of each case. Sometimes such cuttings
are altogether unnecessary or undesirable, in others one good
cutting suffices, and in others again two or even more are
required.
The period over which the preparatory stage extends com-
prises sometimes only one or a few years, at other times as
5i80 NATIHAI. UKCiKNKltATKtX OF \V()UJ)S.
much as ten or even more years. In the hitter case the cut-
tings should be light and freciuently repeated. Generally, the
cover should not be interrupted to any considerable extent
during the preparatory stage, except, perhaps, towards the
end of it.
In selecting the trees to l)e cut during this stage, a com-
mencement is made by the removal of diseased trees, and all
species not required or desired for reproduction ; then trees
with bad crowns are chosen, followed by those with excep-
tionally broad crowns, care being taken throughout that the
trees destined for the ultimate shelter-wood are as evenly
as possible distributed over the area, and give the shelter
required for the species under regeneration.
Ji. Sccdinij Sfaiio.
If the process of preparatory cuttings has been allowed to
take its regular course, it will result in the locality being
graduall}^ brought into a condition fit to produce a new crop,
which springs up and occupies the ground. Such is, however,
rarely the case in practice, because the seed years come at
irregular intervals ; hence, to avoid the risk of opening out
the old wood too early, it is desirable to hold back a little with
the preparatoiy cuttings. When a seed year actually comes,
the regeneration area is frequently not quite ready for it, and
it is found necessary to make an additional cutting, which is
called the " seeding cnttinijy 13y this measure all trees are
removed which are not required afterwards for shelter or the
further production of seed.
It is evident that the marking of the seeding cultin<,f should
1)0 made only when the seed is actually on the trees and
sufticiently advanced to be depended on. The cutting can be
made shortly before, during, or after the fall of the seed.
Cases in which this rule may be departed from are compara-
tively rare, for instance, on thoroughly fresh or moist soil, and
in the case of a species which seeds regularly every year.
The important question at this stage is the density of the
THE COMPAKTMENT SYSTEM. ^3l
shelter- wood which remains after the seeding cutting has been
executed. That density must be such as to ensure the most
favourable conditions for the further advancement of the
3^oung crop ; in other words, it must aft'ord sufficient light to
the young crop without exposing it to injury by frost, drought,
or excessive weed growth ; at the same time there must be
sufficient shelter left to affect the general factors of the locality
beneficially.
It will be easily understood that, apart from the species,
the density of the shelter- wood depends on a variety of
circumstances, of which the following may be mentioned : —
i. CuNDITIONS OF THE LOCALITY.
The shelter-wood should afford protection against the drying
up of the soil, frost, cold winds, growth of weeds, and perhaps
also against damage by insects. In localities where the young
crop is threatened by one or more of these dangers, the
shelter-wood must be kept dark; amongst them may be
mentioned poor, loose, stony soils, southerly and westerly
aspects, steep slopes, localities exposed to dry or cold air
currents or to great changes of temperature in spring result-
ing in late frosts, those inclined to a strong growth of weeds,
especially calcareous soils, where wind falls are apprehended,
or where cockchafers and other insects are likely to settle.
Where the opposite conditions prevail, in other words on
generally favourable localities, the shelter- wood may be less
dark, with a comparatively light cover overhead.
ii. Condition of the Shelter-wood.
Old trees have comparatively denser crowns than younger
trees. Tall trees give less shade than short ones. Both
circumstances must be considered in determining the number
of trees to be left for the shelter- wood, so as to produce the
desired density.
iii. Degkee of Prepakation arrived at during the Preparatory Stage.
The higher that degree, the lighter may be the shelter- wood,
other conditions being the same. Whenever the preparation
'2:iZ NATURAL HH(iENEUATK>N Ol" WOODS.
has been insufficient or faulty, it is desirable to keep the
shelter-wood comparatively dark, because the seeding maj'
fail or be incomplete, so that a second seed year must be
awaited before the area becomes completely stocked with a
new crop.
iv. Si'KciKs.
Above all, the nature of the species determines the density
of the shelter-wood. Tender species, especially those of slow
growth during youth, require a dark shelter-wood ; hardy,
light-demanding, quick-growing species a much lighter one.
In the case of the latter, the distance of the shelter trees may
be governed only by the distance to which the seed is naturally
disseminated.
V. t;i;NKi;Ai,i.Y.
The cover of the shelter-wood should be as even as possible
throughout whenever the conditions are uniform over the
whole regeneration area ; if they differ from i)lace to place,
the shelter-wood must be arranged so as to suit the changes.
Along the edges of the wood, especially where exposed to dry,
cold, 01- strong air currents, the shelter-wood should be kept
dark, and it may be even necessary to provide beforehand a
special shelter belt.
As already indicated, the shelter-wood should consist of
healthy trees with moderate-sized elevated crowns. If trees
with low crowns have to be selected, it is useful to prune the
lower branches away to a height of 15 — '10 feet.
The time for making the seeding cutting may be, as stated
above, shortly before, during, or after the fall of the seed ;
it must be concluded and all the material removed before the
seed begins to germinate. In felling the trees care must be
taken not to hijure those which remain as the shelter-wood.
The proper time has now arrived for considering whether
any artificial working of tlie soil is required. Should this be
the case, it can be done as indicated on page 158. Where
root wood is saleable and the removal of the stools desirable
• )n other grounds, the trees conipiised in the seeding cutthig
THE COMPARTMENT SYSTEM. 233
may be grubbed out, thus ensuring a considerable amount of
working of the soil.
If the working of the soil is done after the seed has actually
fallen, the latter is thereby brought into the ground. The
depth of such working depends on the natm-e of the seed ; it
may be deeper for large seed, such as acorns, beechnuts, and
chestnuts, but it must be shallow for small seeds. At this
period the question what to do with any advance growth must
also be decided. Many foresters clear it away, so that the
young crop may be as uniform as possible ; others leave
really heallliy groups of it to form part of the new wood;
ordinary underwood of other species must be removed.
From this time forward the regeneration area must be
carefully protected against the removal of litter, cattle grazing,
and grass cutting.
f. Final Shige.
The final staye comprises the period from the execution
of the seeding cutting until the ultimate removal of the
shelter- wood.
The principal objects of the shelter-wood, after the ground
has been stocked with a crop of seedlings, are to protect the
young growth against various dangers and to preserve tbe
activity of the soil until the new' crop can undertake that duty.
At the same time the shelter-wood will act obstructively as
regards the admission of light and precipitations, and therefore
it must not be left longer than is actually required. Its
removal is effected, so as to meet these various requirements,
by one or several successive cuttings executed at intervals of
one, two, or more years. The rate at which, or the time
within which, the removal takes place depends on various
considerations, such as the following: —
i. Activity of the Soil.
The preservation of a suitable degree of moisture in the
soil is of first importance. Owing to the action taken during the
preparatory- stage, the degree of moisture in the soil may have
■i'-U NATURAL KKdENKHATloN OK \VO()J>S.
been iinj)eiille(l. From tlie moment tliat a new crop lias
actually sprung up, the considerations which prompted the
measures taken during the preliminary stage disappear ; it
becomes the duty of the forester to do his utmost to give to
tlie soil all the slielter available after due consideration of
the reijuirements of the young crop, and to re-establish as
quickh' as possible a fresh and substantial layer of humus on
the ground.
Until the new crop closes overhead, therefore, the old wood
must provide a certain amount of shelter, and the leaves
falling from it will form the nucleus of the new soil
covering. On steep slopes the remaining shelter trees help
also to prevent damage by water rushing down the hill side.
At the same time the cover of the shelter -wood during the
final stage is already much interrupted, and not too much
must be expected from it ; in some cases it may even act
injuriously, as it may deprive the soil of more rainwater and
dew than is preserved by the beneficial action of the crowns
of the trees.
ii. FliusT.
As regards frost, the shelter-wood does good service In-
reducing radiation ; it is less effective against cold air
currents, unless it is supplemented by a dense shelter belt
or wind break along the edges of the wood. Most species are
liable to be injured by frost during early youth, and some
require protection against it for a consideral)le numl)er of
years.
iii. W'l-.Ki.s.
Here again tlie shelter-wood acts beneficially, l)y preventing,
or at any rate retarding, the springing up of weeds, thus giving
time to the new croj) to increase in height before it has to
contend with them.
iv. Inskits.
Experience has shown that damage by insects is in many
cases less pronounced under a shelter-wood than on clear
cuttinitribtttion of tJtc i/icUl over the several 3'ears and the
state of the market frequently interfere with the timely execu-
tion of the cuttings. Similarh', the occurrence of a seed year
may necessitate a suspension of cuttings in the areas stand-
ing in the final stage. These matters are not conducive to a
healthy development of the young crop, but the drawback is
to some extent compensated by the heavy increment laid on by
the shelter trees, which increase rapidly in size and value.
The absolute d it ration of' tin- final stiKjc differs considerably
according to species tUid the special conditions of each locality.
In the case of some light-demanding hardy species, and in
favourable localities, it may not be longer than from three to
five years, while it may extend over 10, 15, and even more
years in the case of tender species, in unfavourable localities,
and where the object is to increase the size and value of the
shelter trees in their ro(miy i)osition.
In executing the fellings in this stage special care must be
taken to avoid injuring the young growth. The trees raustl)e
lopped, if necessary, before felling, and they must be thrown
in that direction in which they are likely to do least damage.
Fellings should not be made during frost unless deep snow is
on the ground, as the young growth is then very brittle. The
material must be taken out of the wood by means which cause
a minimum of damage, and, if possible, before the next growing
season commences.
If, after the reniuval of the last shelter trees, bianl^s of
ai)pi-ecialile extent exist, they must be ai-tilicially tilled up by
THE STRIP SYSTEM. 237
planting strong plants on them, and in some cases perhaps 1)y
sowings.
<1. Mdilcinn the Trcrs for Eoinot'nl.
What has heen said above shows clearly, that the success
of natural regeneration by seed under a shelter-wood chiefly
depends on a suitable composition of the latter during the
several stages of the regeneration period, in other words, on a
careful selection of the trees to be removed. Except in the
case of experienced foresters, this must be carried out when
the effect of the removal of a portion of the trees can be best
judged, namely when the trees are in leaf. In the case of
evergreen species the marking can be done at any time, but
in woods containing deciduous species the marking should be
done in summer or early autumn before the leaves fall. In
carrying out the marking only a narrow strip should be taken
in hand at a time, and the business should be supervised by a
competent and responsible forester.
2. The Strip Sj/stent of Natural Kerieiwration under
Sltelter-woods.
As already mentioned, this system is a modification of the
compartment system. Instead of conducting the regeneration
process uniformly over a whole wood or compartment, the area
is divided into a number of narrow strips, which are taken in
hand, one by one, at such intervals, that generally three strips
are under regeneration at one and the same time ; one being
in the final stage, one in the seeding stage, and a third in the
preparatory stage. As soon as one strip has been completely
regenerated a fresh strip is taken in hand, and so on, until tlie
process is gradually extended over the whole compartment or
wood. In the appended Figs. 75 and 76, the strip marked /'
is in the final stage, that marked s in the seeding stage, the
one marked j^ in the preparatory stage, and the rest of the
area marked ii is forest as yet untouched. The process of
regeneration in each strip is the same as that described in the
238
NATT'RAL REGENERATION OF WOODS.
ciiKe of the compartment system : there are the three stages,
one folh)\vin«.' the ntlier.
N.lUTH.
Eam
NoHTir.
Wkst,
Nothinf^ definite can l)e said re<^'ai-dinn; the breadth of the
strips ; it depends on the species and tlie local conditions.
THE GROT'P SYSTEM. 239
Those wlio advocate the system sa}- that, ordinarily, the
breadth should not exceed the height of the trees. There
is no limit to the length of the strips.
The operation should generally commence on that side of
the wood which is opposite to the prevailing wind direction :
this rule may be overridden by other considerations, for
instance an unfavourable distril)utibn of the age classes.
In some cases the wood may, if necessary, be attacked in
two or more places at the same time.
For the rest, little or no difference exists between this and the
compartment system, except that the area under regeneration
is less concentrated in the former.
3. The Group System of Xatiiml Regeneration under
SJielter-woods.
If a forest is naturally regenerated under the compartment
system it may happen that, after the seed cutting, the area is
not, or only partially, stocked with a new crop. A second
seed year must then be awaited, and in the meantime, the
cover having been thinned, the soil may suffer considerably
under the additional admission of light, so that it may not
present a fit germinating bed when the second seed year
arrives. Extensive working of the soil or artificial forma-
tion has then to step in. With the view of reducing this
drawback to a minimum, foresters hit upon the idea of taking
in hand in the first place only certain limited groups, scattered
over the compartment ; when these have been successfully
regenerated, they proceed with a second set of groups, and so
on, until the whole compartment has passed through the
process of regeneration. In practice, the system has been
further modified : certain groups, as before, are taken first
in hand, and when these have been regenerated, they are
gradually enlarged by regenerating successive narrow bands
around them, and this process is continued until the several
groups merge into each other (Figs. 77 and 78). The time
required for the completion of the process in each wood, or
iO
NATntAI, HEGKXKHATION Ol' WOODS.
compartment, is considerably lonj^Pi- tlian midei' tin- compart-
ment system, and it extends generally over a period of 20 to
50 years, according to species and local conditions.
A wood, while l)einp; regenerated under this system, presents
a varying picture : some" parts of it have been completely
1, 1, 1. Points of attack (j^rmips of advance gniwtli;.
2. 2, 2. I
;j '.i 15 ,
' ' ',' ',' - Successive eiilarffoinciits of groups.
.'), 5, n. I
regenerated, others are more or less advanced in the process,
and others again are as yet untouched, with a complete cover
overhead. When the whole process has been completed the
young wood consists of trees varying in age by 20 to 50
years, according to circumstances ; it is in fact an uneven
aged wood.
THE GROUP SYSTEM.
24.1
a. Selection of Groups.
The time when the different parts of the wood are attacked
depends chiefly on the following considerations : —
i. Advance Growth.
In almost every mature wood groups of young growth are
found, which have sprung up, here and there, before the
Fig. 78. — Elevation of a section along a 6 of Fig. 77, in four
successive stages.
regeneration cuttings have been commenced ; such young
growth is called "advance growth." Under the uniform
s. H
24-^ NATlliAL KEGENEKATIUN OF WOODS.
system it is not iiuich valued, partly because it f,'ives the
youn<; crop an uneven character, and partly because, having
stood for some time under the shade of the old crop, it is not
always capable of developing into healthy full-sized trees ;
hence, it is frequently removed altogether to make room for a
uniform new crop. Under the group system all patches of
advance growth, which are still healthy and capable of
developing into full-sized trees, are carefully husbanded.
They form the nuclei of the first regeneration groups ; the
old trees standing over them are removed when no longer
required, then the groups are enlarged, as indicated above,
by gradually cutting away the immediately adjoining trees in
narrow bands.
ii. DlKFEUEXtKS OV Ann, CUOWIII. CnVKl:, AMI Sl'KCIKS.
Many old woods are naturally of uneven age. In such cases
the oldest parts are first taken in hand, followed by the next
age gradation, and so on.
Again, certain parts, for one reason or another, have not
kept pace in development with the rest, nor are they likely to
make up for it. They should be taken in hand first, so as to
avoid loss of increment.
Frequently certain parts have thiinied out naturally,
followed by an hiterruption of the leaf canopy ; they must
be attacked tirst of all.
In mixed woods, groups of dilierent species may require
regeneration at diti'erent times, ofifering an additional
opportunity for a judicious selection of the groups first
to be taken in hand.
iii. I)ikiart of the
State forests of Germany and France, where natural regenera-
tion is adopted, though there is evidence that it will, in many
cases, he superseded l)y the group system.
The S3'stem partakes of the character of the compartment
system carried out on small compartments ; the danger of
failure over a large continuous area is avoided, and the
shelter-wood is less liahle to be blown down, but tlje
operations are less concentrated.
'■. 7'/ir (//■('>'/) Sijslrtn.
(1.) Tlie drawbacks are, that the operations are scattered
over a largei- area at one and the same time, rendering super-
vision more difficult and the transport of the material more
expensive.
(2.) The principal advantages of this system over the
compartment system are : —
(a.) It insures a more complete preservation of the factoi-s
of the soil ;
(//.) It affords greater security, especially in the case of
shade bearing tender species, as regards the success
of the regeneration, because it is carried out on
small scattered areas at one time, so that failure
in one does not imply failure in the others ;
{<■.) Each group can be taken in hand when the most
favourable moment for regeneration has arrived ;
[(I.) The removal of the shelter-wood causes less damage
to the young crop, as the material can be transported
through the parts of the wood not yet regenerated.
(8.) In summing up, it ma_y be said that the group system
is in its place where the conditions of the locality or of the
crop cliange from place to place, or where extremes of climate
l)revail. It is admirably' adapted for the regeneration of mixed
REGENERATION FROM ADJOINING WOODS. 247
woods, as it affords excellent opportunities for securing a proper
mixture of the several species in the new crop.
Above all, it is specially adapted for the introduction of a
more regular system of working into selection forests.
d. Tlir SclerHon Si/sfem.
Here the drawbacks of the group system are further mten-
sified, without offering sufficient compensation by way of
advantages in other respects. True, the soil is still more
completely protected, but this is generally accompanied by
withholding from the young growth a suital)le measure of
light.
The system is, in Europe, confined to localities where the
uninterrupted maintenance of a crop of forest trees is neces-
sary for the protection of the soil against heavy rain, snow,
wind, etc., in fact for so-called protection forests in high or
steep mountains. It is also useful in forests of specially small
or large extent ; in the former, if the area is insufficient for a
regular division into compartments, and if nevertheless a
certain quantity of timber is required annually ; in very large
forests which are as yet in the first stage of systematic manage-
ment, such as many of the forests of India. It is also prac-
tised, generally in a rude form, where the demand for produce
is as yet much below the supply.
B. Natural Regeneration from Adjoining Woods.
After the area has been clear cut, the seeding is effected by
the seed falling from mother trees, which do not stand on the
cleared area, but alongside of it.
The points which demand attention are the conditions of
success and the merits of the system.
1. C()H(Utio)is of Success,
a. Sufficient Seedin(j of the Area.
The agencies which carry the seed on to the area are air
currents, and in some cases water, or the seed may roll by its
248 NATiHAi. kk(;knej{atiun ov woods.
own weight down a slope. ^Vllen air cunents are the carrying'
agency it is necessary that tlie seed should be sufficiently liglit,
and that when it falls the wind should blow from the right
direction. In this respect the species, the force of the air
current, and the relative position of the regeneration area and
the mother trees are of importance. The seed of some species,
as poplar, is so light that it travels for miles, while that of
others falls straight to the ground. Gayer gives the following
distances for a number of species under the influence of a
moderate air current.
Birch, elm, larch, 4 — 8 times the height of the trees.
Spruce, Scotch pine,
alder .... 3 — 4 ,, ,, ,,
Maple, ash, horn-
beam .... 2 — 3 ,, ,, ,,
Lime, silver fir . . 1 — 2 ,, ,, ,,
Beech and oak, scarcely beyond the reach of the crowns.
In the case of strong winds the distances are proportionately
greater ; instances can be seen in Scotland where Scotch pine
seed has been carried to many times the distances given above.
The distances are also greater, if the mother trees stand at a
higher elevation than the regeneration area.
The direction of the wind during the fall of the seed intro-
duces a great element of uncertainty, as it can only in rare
cases be relied on.
A further complication may arise if the seed sliould fall
during the prevalence of a dry east wind, while, for other
reasons, regeneration should commence in the east and
gradually proceed towards the west.
Ik Siiihihle Coiiililinn of the (Hfrminaliini llrd.
This has often to be provided by working, or woimdiiig the
soil. Where the roots of the trees are grubbed out the soil is
sutiHciently stirred, but where the stools remain in the grou)ul
wo)kiiig may be necessary.
REGENERATION FROM ADJOINING WOODS. 249
c. SecurHij (ujainst crfernal Ddnijcis.
These are chieflj^ frost, drought, and a growth of weeds.
Some protection will be given by the adjoining wood, but the
amount depends on the breadth of the area under regeneration
at one time, and the relative position of the mother trees.
(1. Extent of the (J tear inn .
The smaller the regeneration area is, the more satisfactory
will be the results. On large areas a period of 10. 20, or more
years may be required to complete the new crop, which will
be very uneven, and in the majority of cases artificial sowing
and planting has to step in.
The chances of success are much greater if the regeneration
area has the shape of a narrow strip running along the edge
of the mother trees. The breadth of such strips should not
exceed the height of the mother trees, so that the area may
l^e quickly and fully stocked, and better protection provided
for the young crop against climatic dangers ; the soil keeps
also fresher.
Such protection is further increased if successive clearings
do not adjoin each other, but are separated by older woods.
Sometimes the clearings represent patches situated in the
middle of old woods. Arrangements of this kind lead, how-
ever, to a verj' complicated system of management ; lienee
they occur only where groups of trees have been thrown by
wind or snow, or killed by insects. If patches are cut
purposely, they often lead to the group system described
above.
2. Merits of the System.
Owing to the uncertainty of the seeding and the injuries to
which young tender plants are exposed, the system can be
recommended only under favourable conditions of the locality
and in case of hardy, quick growing species. Damage by
insects, especially the cockchafer, Hylesinus, and Hyhirgus,
further narrows the limits of applicability.
:2o(l NATl'HAL HKGENHHATION OF WOODS.
SkcTION 11. NaTLHAL PiEGKNKItATloN 1!V SllnoTS AND
SUCKKRS.
It lias been explained in Part I.,* that woody plants can
reproduce themselves b}' means of shoots, or suckers, or botli.
Shoots may sprinp; from the stool, after the tree has been cut
over close to the ground, or from the stem and top. if the
cutting is restricted to the side branches and the upper part
of the stem. Accordingly a distinction may be made between
regeneration from the root, stool, or stem. Of these, repro-
duction by stool shoots is b}' far the most important, but as in
many cases it occurs in conjunction with reproduction by
suckers, the two will be dealt with together.
1. Refimeratio)! In/ Sfool SJinotn and Siicl.rys.
As already stated, regeneration follows the cutting over of
the trees. Where stool shoots are wanted, the cutting over
takes place close to the ground, followed by a clump of
shoots which spring either from adventitious buds formed
on the callus near the edge of the cut, or from dormant
buds on the neck of the stool. A similar mode of cutting is
employed where both stool shoots and suckers are wanted.
If only the latter are desired, the stump may be removed, and
only the roots left.
The success of this system of I'egeneration depends on many
things, of which the following require special attention.
Of the species growing in temperate Europe only broad
leaved trees and slirubs are adapted to the method, and even
amongst these great differences exist in regenerative power. t
0. Af/et'f Wooil nl 7'i/nr (>J[ ( 'i/lli/i;/.
Generally, reproduction is most powerful during youth up
to the period of principal height gi-owth,and under favouralde
• Spc paeo fi". i Soo pajzf <>",
REGENERATION BY SHOOTS AND SUCKERS. 251
ircumstances for some time beyond it. Hence the wood must
be cut over for ihe first time at a period not lieyond the end
of the principal height growth. After that, the rotation
depends on the required description of material (firewood,
hop poles, bark of a certain quality, etc.), and the time up to
which the stools are capable of vigorous reproduction.
The increment of coppice woods is also greatest during the
first few' 5'ears after cutting, which may be another reason for
the adoption of short rotations. On the other hand, small
material has of late years so much sunk in price, that the
w^oods are frequently allowed to grow until they are capable of
yielding small timber.
c. SoiinilDOKs nf Sfodh.
Diseased stools often produce diseased shoots, though some
species, as oak and hornbeam, are usually exempt from this
liability ; tlie same holds good in the case of suckers. It
follows that diseased stools should be removed and replaced
by strong plants to produce fresh and sound stools.
The longevity of the stools is closely connected with their
health, which is principally governed by the species and the
character of the locality. A fertile soil and favoural)le climate
increase the longevity. The stools of ash, maple, birch, and
also those of beech, are short-lived, lasting frequently not
longer than two or three rotations ; those of oak and horn-
beam are almost indestructible, and between these extremes
many intermediate stages exist.
d. Man tier of Vtdfiinj.
The cut produced by the removal of the stem is exposed to
the effects of air, moisture and sun, which cause a deteriora-
tion of the wood near the cut through drying up and rot, and
tend to reduce the reproductive power of the stool.
Although this process of deterioration cannot altogether be
prevented, its extent and rapidity can be reduced by careful
cutting. In the first place the size of the cut should not be
252 NATTRAI, HKGKNKHATION OF WOODS.
ton liiif^e, ill the second place it should he smooth, and linally
it slionld he slanting, so that water may not rest on it
(Fig. 79). In the case of large slioots, the cut may he given
a slope from the centre to two sides, or it may receive the
sliape of a cone (Fig. 80). The cut should on no account slope
inwards (Fig, 81) ; it should be made with a sharp billhook or
axe, and not with a saw. If the latter is unavoidable, the cut
should be given a smooth surface with a billhook, axe, or
knife. Another important point is that the bark should not
be severed from the wood around the edge of the cut.
The height from the ground at which the tree is cut over
also influences the success. Except where inundations are
feared, it is preferable to cut close to the ground, and there is
less corky bark on the root neclc : besides, if the shoots appear
^^^^^■'ii^w.v-
Good.
11,,./.
Fi,f.
Fig. -i).
low down, at or a little below the surface, they are more likely
to develop independent roots, and thus ensure greater
longevity of the stool.
In southern countries, where the sun may diy up llie stools.
it may be necessary to cut below the ground, or to cover up
the stools with earth.
c. Season ,if CiiUiiiij.
The best seasmi of the year for cutting is a few weeks before
tlu! buds be^^iii to swell. Various circumstances may, how-
ever, prevent this being done, such as an insuihciency of
labour, the necessity for peeling the wood, etc. ^Vhere labour
is not available to do the whole cutting at the most favourable
period, a part must be done (in Europe) hi the autumn ; tliis
has the drawback that frost during winter frequently separates
REGENERATION BY SHOOTS AND SUCKERS. 353
the bark from the wood of the stool, or that the stools are
killed outright. Again, stools which were cut over in autumn
send out shoots somewhat earlier in spring, and thus render
them more lial)le to be injured by late frosts.
Where the principal object is to obtain bark for tanning,
the cutting must be done during the full flow of the sap, that
is to say, in temperate Europe, in May and the beginning of
June.
/. Standanh.
The reproduction is most complete if the wood is clear cut ;
the more standards are left, the less favourable will be the
crop of shoots and suckers.
2. Rcproduct'uDi hy Stem Slioot!^, or PoJJardiiui.
Pollarding consists in the removal of the crown of a tree,
either leaving the main stem intact or cutting it off at a
certain height from the ground ; in tlie latter case the system
is frequently called topping. The branches may be cut off
close to the main stem, or at a short distance from it, the
latter method being preferable. New shoots spring from the
cuts, and these are again cut after one, two, or more years,
according to the desired size of the produce.
What has been said above regarding species, health of the
mother trees, and manner and season of cutting, holds mostly
good also as regards pollarding. The system is chiefly
employed in the case of willows and poplars ; the former
yield materials for basket work, fascines, hurdles, etc., and
the latter firewood and small sticks for domestic use.
^.04
CHAPTEli l\.
FORMATION OF MIXED WOODS.
The various methods of foniiin;^ }i wood described in tlie
previous chapters of tliis part are appHeable to both pure
and mixed woods. There are, however, certain peculiarities in
the formalii)ii of mixed woods, which it will be necessary to
indicate. As the number of possible mixtures is very larj^e, a
separate reference to each is impossible. It must sufltice to
deal with them in the following groups : —
1. Formation of even aged woods, or in which the ages of
the species in mixture differ so little that they may. for
practical purposes, be considered as even aged.
2. Formation of mixed woods consisting of trees of uneven
age, such as high forest with standards, two-storied
high forest, etc.
1. r'oniiatio)! ()f Ernt At/rd Mi.vcil Woods.
In Fart I. of this volume (i)age 74). it has been explained
that in order to preserve mixtures in which the species are of
the same age, the latter should show nearly the same rate of
height growth throughout life. Whenever this is not the case,
any species sensitive to cover and likely to be outgrown by
associated species must be given a start, while the latter must
be capable of bearing the shade of the former. In the absence
of these conditions the species must be separated, and the
utmost which can be done is to place them in alternating
groups. Even then there is no certainty that in regenerating
such a wood the new crop will show the desired mixture.
At any rate it will be clear that the regeneration of such
woods requires constant attention, lest one species should
oust another.
EVEN AGED MIXED WOODS. 1^55
a. Sowiiu/ and PlanUnfi in Clear Gutting^.
Sowing can be done by mixing the seed of two or more
species, or by sowing one over the other, either direct or
crosswise. The second method must be followed whenever
the seeds require a different covering, that which requires
the deeper one being sown first. Another method is to sow in
alternate strips. Sach sowings are rarely made nowadays,
but recourse is had to planting, as it permits the .mixture
being arranged in any way which may be desired. The
species may alternate by single plants, or by lines, or
strip- or group-wise. Again the proportion of one species
to another can be absolutely fixed. Planting in groups is
specially indicated where the conditions of the soil change
from place to place, as each patch can receive the most suit-
able species. The size of such groups depends on circum-
stances ; if it exceeds a certain limit, the wood can no longer
be considered mixed — it becomes a series of pure woods.
Where a light demanding species is to be mixed with a
shade bearer, the former can be given a start of a few years,
instead of arranging the mixture by groups. In such cases
the mixture is frequently arranged by lines, the light demand-
ing (and generally hardy) species being planted first in alternate
lines, and the shade bearing species (generally tender in early
youth) afterwards in the intermediate lines.
Another way of giving one species a start over another is to
put in plants of different ages.
In some cases one species is raised with field crops, while
the other is planted in, when the cultivation of the field crops
has ceased.
Formerly it sometimes happened that one species was raised
by sowing and the other by planting, but this is rarely done
nowadays.
h. So/ring and Planling under SlifUvr-woinh.
This method is followed in the case of species which are
tender during youtli, especiall}' in respect of frost.
256 FORMATION OF MIXKl) WOODS.
If an old wood exists, and a new mixed wood, consisting of
a tender and a hardy species, is to be created, tlie former may
be sown or planted alone under the shelter-wood ; llien, when
the shelter-wood is no longer required, it is removed, and the
second, hardy species planted in. This method is followed,
for instance, where beech is to be mixed with Scotch pine or
larch.
If no old shelter-wood is available, then the hardy species
is cultivated first, and when it has advanced sufficiently to
provide the necessary shelter, the tender species is intro-
duced. In this way Scotch pine, larch and birch are planted
to serve as shelter- woods (nurses) for beech, silver fir, and oak.
c. Xdiural Rcucncrdiiiin wider S/ielfer-troot/s.
In regenerating a mixed wood it is of first importance that
the shelter-wood should be composed of trees of the several
species in such proportion as to secure the desired mixture in
the new crop. In determining that proportion the relative
reproductive power of the species must be taken into con-
sideration, more especially the size and quantity of the seeds,
the frequency of seed years, the height growth of the species
in early youth, and its capacity of bearing cover ; its degree of
hardiness, the nature of the germinating bed, vIvc,
Already during the last thinnings the cuttings can be so
arranged as to lead to a proper proportion of the mother trees.
This process is continued, and if possible completed, during
the preparatory stage. Under any circumstances it must be
completed by the seeding cutting.
In many cases a great difficulty arises from the fact that
the several species do not seed in the same year. In such
cases the seeding cutting must be made, when that species
seeds which is to form the Inilk of the new crop, or which is
the more difficult to rear ; the other species, if they have
not produced a sufficient proportion of seedlings beforehand,
or fail to do so within a few years afterwards, must receive
artificial assistance.
EVEN AGED WOODS. 257
The arrangement of the cuttings during the final stage
depends on the requirements of the new crop in the several
parts of the wood. Where conflicting interests present
themselves, those of greater importance must prevail.
The trees to be left for the final cutting should belong to
the most wind firm species, to that which is most likely to
increase rapidly in size and value, and if possible to one with
a thin crown.
The above remarks show that it is in many cases a difficult
task to guide successfully the process of refieneration in a
mixed w'ood ; hence a method should be chosen which reduces
the difficulties to a minimum. With this end in view the
several species may be brought together in groups, each of
which can be treated in the manner best adapted to the par-
ticular species. If this should be found insufficient, the
following method must be adopted : —
(I. Natural Rfgeiwralidii coinhiiied u Ith Sowiiiy and Plantiaij.
Natural regeneration alone rarely leads to the desired result ;
only parts are successfully stocked, and sowing and planting
must step in to complete the business. In applying this
method it must be remembered that generally the more
favourable parts of the area become naturally stocked,
leaving the inferior spots blank. If only the latter were
filled up by sowing or planting the species which is deficient
in the naturally regenerated patches, it would be relegated to
the bad spots, while the other species would occupy the better
parts ; hence it is necessary to plant a proper number of the
artificially reproduced species also within the patches already
naturally regenerated.
This method is much used in Europe in the formation of
mixed woods of beech with oak, ash, sycamore, and other
valuable timber trees. In fact it is the best method for such
mixtures. The valuable species are generally introduced by
putting in strong plants ; sowings are also done in the case of
.• s
258 FORMATION OF MIXED WOODS.
shade bearing species, or where the species are arranged in
separate groups.
Another instance is the regeneration of silver 11 r and spruce
woods in the Black Forest. There silver lir is favoured during
the regeneration process, and if an insufficient number of
spruce plants has sprung up, it is afterwards increased by
planting.
2. Formation of Mixed Woods oj Uneven Age.
It has been shown that the preservation of the mixture is
difficult, when the trees ai-e of the same age, or nearl}- so, and
that it requires constant care and attention, lest one species
should be suppressed b}^ another and disappear. Such unre-
mitting attention cannot always be given, apart from the
expense which it involves. Endeavours have been made,
therefore, to devise a method of mixing species which is less
dependent on constant attention, and this has been found in
giving to the mixed species a greater difference of age. Such
an arrangement causes a considerable difference in the ages of
the component parts of the wood. Each of these requires to
be regenerated at its own time, so that the process of regenera-
tion is gone through several times in the course of one rotation,
one part of the wood being regenerated on each occasion.
Many varieties of mixed woods of uneven age have been
evolved, each of which corresponds, more or less, with a
distinct sylvicultural system. Of these the following claim
attention : —
(a.) The group and selection systems.
{h.) High forest with standards.
(o.) Two-storied high forest.
{d.) Mixed coppice with standards.
a. The Grovp and Seler/ion ,^f/s/ems.
Under the group system the regeneration of a wood extends
over a period ranging up to 40 and even 50 years. By first
regenerating the groups consisting of the threatened species,
UNEVEN AGED WOODS. 259
they can be given a start up to 30 or 40 years. After these have
been regenerated, tlie groups consisting of the threatening
species are taken in hand. Taking, for instance, a mixture of
light demanding and shade bearing species, such as oak, larch,
or Scotch pine, ^Yith beech, silver fir or spruce, operations
commence with the groups of the former, and are brought to
a close by a regeneration of the latter.
Again, in a mixture of shade bearers only, such as beech,
silver fir and spruce, the last mentioned is likely to outgrow
the beech and also the silver fir ; hence a sufficient n amber of
groups of beech and silver fir are first established, and then
the groups of the spruce.
In the case of selection forests the differences in age are still
greater, and much can be done on the lines indicated above,
to protect the threatened against the threatening species.
b. Nif/h Forest irith Standards.
If such woods are mixed, the threatened species are selected
for standards, if otherwise suitable for the purpose ; it is
essential that the rotation should not be very high, otherwise
the future standards may suffer l)efore the end of the rotation
has been reached.
c. Two-storied High Forest.
It has been explained in Part I., page 103, that when a high
forest has run through part of the fixed rotation, a portion
of the trees are removed, and a new crop is introduced, which
grows up between the trees remaining of the first crop, the
two being allowed to run through an additional whole rotation.
The difference between the two crops ranges, as a rule, from
20 to 60 years. Here then is an excellent opportunity of pro-
tecting a threatened against a threatening species, the first
crop consisting of the former, and the second of the latter.
In Europe the system is much adopted for the production of
large- sized oak, larch and Scotch pine, also ash, maple and
others, which at a certain age are underplanted with beech,
s2
200 FORMATION OF MIXED WOODS.
silver fir, spruce, hornbeam, sweet chestnut and hazel. This
underpUinting had best be done in the case of larch at the age
of 10 to 20 years, of Scotch pine at 20 to 40 years, and of oak
at 30 to 50 3'ears or even later.
(I. Mixed Coppiro ivilli SfnniJnnls.
This system offers, in the regeneration of the over wood, the
greatest latitude for the protection of threatened species,
whether in single trees or in groups. Although some of the
standards may regenerate themselves naturally, the gieater
part are produced by planting strong plants where mature
standards have been removed.
•261
CHAPTER Y.
CHOICE OF METHOD OF FORMATION.
The choice of method depends on numerous considerations,
such as the sylvicultural system, species, soil, climate, external
dangers, labour, cost, etc. To attempt a detailed exposition
of these matters in reference to the several methods would
not lead to any practical result, since, after all, the choice
depends on the local circumstances of each case. A few
remarks regarding the main groups of methods may, however,
not be out of place. These main groups are : —
(1.) Direct sowing.
(2.) Planting.
(3.) Natural regeneration by seed.
(4.) Natural regeneration by shoots and suckers.
Of these the last-mentioned method refers almost entirely
to coppice woods worked under a short rotation ; it is not
employed where woods are treated under a high rotation,
because in very rare instances only do coppice shoots reach
the same size as seedling trees.
The questions which interest the sylviculturist most are —
(1.) "Whether to sow direct, or plant on cleared areas.
(2.) Whether to regenerate existing woods artificially, or
naturally by seed.
(3.) Whether or not combinations best meet the objects of
management.
These three questions, then, will be shortly discussed in
the following pages.
262 C'HOKK OF MHTHOI* oK FOIOIATION.
Section 1. — Ciioict: ]iET\VKi:N \)in\:ci Sowinc; and I'lanting.
Formerly the artificial formation of woods was chietiy
eflfected by direct sowing, planting being restricted to special
cases where the other method was not likely to succeed. The
reasons for this were, that sowing was considered to be more
certain and cheaper, since it was generally the custom to use
too large transplants. In the course of time the raising of
plants was elaborated, smaller plants were used and the
expense considerably reduced, so that now far more planting
than direct sowing is done. Yet it is not always a foregone
conclusion that planting is better or more suitable than direct
sowing, since many differing conditions and factors affect the
ultimate results. The effect of some of these factors is as yet
somewhat obscure, but in many respects experience has taught
the forester, which of the two methods is preferable under a
given set of conditions. The points of view from which the
choice of method may be approached are manifold, and
amongst these the following deserve attention : —
(1.) Objects of management.
(2.) Desired sylvicultural system.
(3.) Selected species.
(4.) Conditions of locality.
(5.) External dangers threatening the young wood.
(6.) Quality and quantity of available labour.
(7.) Cost.
1. Olijiuts of MdiKKifiiiriit.
The objects of management are shortly indicated on
pages 1 and 2, and it will readily be understood that,
according to circumstances, either planting or direct sowing
may more completely meet them.
Where landscape beauty is the object aimed at, few foresters
would think of adopting direct sowing; where time is an
object and expense of minor importance, the planting of
strong transplants would be most siiitalilc. If the ol)j('ft of
DIRECT SOWING VERSUS PLANTING. 263
management centres in the production of the greatest possible
quantity of small material, with the least possible outlay,
direct sowing would probably yield better results than plant-
ing. Again, for the production of clean timber trees sowings,
with their greater density, in many cases may be more suit-
able than planting, unless the latter be very close and thus
involve a considerable outlay.
Economy in working is one of the leading requirements in
sylviculture. In this respect either sowing or planting may
be preferable, according to circumstances ; experience, how-
ever, shows that where plants of good quality can be raised
at a reasonable outlay, planting yields higher and more
valuable returns than direct sowing, if time be taken into
consideration.
Where the land is required for pasture or grass-cutting,
planting is decidedly preferable, as cattle can be admitted
at an earlier age, while grass-cutting can be commenced
at once.
2. Si/lvicultural System.
The formation of woods to be treated under the pollarding
system, and of osier beds, is best effected by planting. The
same may be said of ordinary coppice woods and the produc-
tion of standards in coppice. In ordinary seedling forests,
either method may be adopted.
3. Species.
The species affects the choice of method in various ways.
In the first place many species produce seed abundantly only
at irregular and often long intervals ; hence continuous opera-
tions can be carried on only by planting, as the production of
nursery plants requires comparatively small quantities of seed,
and this, if necessary, can be obtained from a distance. By
keeping a quantity of reserve plants in the nursery, seedless
years may be tided over without interrupting the work.
Species, the seed of which germinates with difficulty or
slowly, or the seedlings of which are tender in early youth.
2d4- CHOICK OF MKTHOI) OF FORMATION.
should be propagated in llic case of clear cuttings by planting
and not bj' direct sowing. In such cases it is much easier
and cheaper to provide the necessary tending and protection
in a compact nursery than on an extensive forest block. Under
shelter-woods direct sowing may be preferable.
Hardy species, which grow slowly during youth, should be
planted ; those of fast and early development may be sown
direct, if this be desirable on other grounds.
The shape of the root system is also of importance. Species
which develop a compact and comparatively shallow root system
are much easier to plant than those which at once develop a
deep going tap root ; for the latter, direct sowing may be advis-
able. Long tap roots, however, may be pruned, or the seedlings
raised in such a manner that they are forced to develop a
compact root system ; at the same time either alternative may
be of doubtful expediency.
Mixed woods should be established by planting, as a proper
mixture of the species is rarely practicable by direct sowing ;
at any rate some of the species must be planted. Frequently
it is desirable to give one species a start over another, and
this can be done in a satisfactory manner liy tlie use of large
plants.
In the case of some species, as for instance oak, many
foresters maintain that direct sowing gives more vigorous and
better trees, but this depends to a large extent on the soil and
climate, and also on the size of plants used.
If sowing of acorns is not advisable for other reasons, the
planting of one or two years old oak seedlings close together
is likely to yield just as good oak trees as direct sowing.
4. Conditions of Locality.
As a general rule it may be said, that planting is preferable
whenever the conditions of the locality are unfavourable,
especially where extremes of soil and climate prevail, while in
a favourable locality direct sowing may yield eijually good,
and in the ease of some species even better, results.
DIRECT SOWING VERSUS PLANTING. 265
Unfavourable localities are those with a wet, occasionally
inundated, or very moist, heavy, cold soil ; excessively loose,
dry, or poor soils ; those subject to be overrun by a heavy
growth of weeds, or where frost lifting may be expected.
Similarly, planting is far preferable to direct sowing where
extremes of climate prevail, such as in raw, frosty, exposed
localities.
On steep slopes planting is also preferable, but in very
stony soil direct sowing may become a necessity.
5. External Dangers.
Seeds, as well as young seedlings, are subject to attacks by
various animals, against which they can be more eli'ectually
protected in a nursery than in the forest ; hence, on this
account, planting is preferable to direct sowing. As regards
attacks by insects, it is an open question which of the t^vo
methods is preferable. As long as only thoroughly healthy
plants are used and put out with care, they may hold their
own and even do better than seedlings in direct sowings ; but
weak plants, or those which have difficulty in establishing
themselves quickly in their new home, are more subject to
attacks by insects than seedlings grown in situ. The same
often holds good as regards attacks by fungi.
6. Labour.
Unless direct sowings necessitate a thorough working of the
soil, they require less labour than planting. Where labour
is scarce direct sowing, therefore, may prove to be cheaper.
Planting also requires more skilled labour than direct sowing.
7. Cost.
Whether direct sowing or planting is the cheaper method
depends on the price of seed, the extent to which the soil has
to be worked for direct sowings, and the cost of plants. Direct
sowing is generally cheaper, but if seed is expensive and
266 tHOK'K OF METHOD OF FORMATION.
small plants can be utilised, plantin«^' may be the less costly
method of the two.
Section II. — Choice jjetwken Artificial Regenef.ation and
Natural PiECiENERATioN ry Seed.
Sowin<^ and planting can be done under the shelter of the
old wood, or it can follow a clear cutting ; natural regenera-
tion can be done under a shelter-wood, or on cleared areas of
moderate breadth by seed coming from an adjoining wood.
The differences between the two shelter- wood methods are
small, while they are considerable between the clear cutting
and shelter-wood methods. The following remarks refer
chiefly to the latter case.
1. Merits of Artijicial lictinirratio)!.
(I. AiU'ditlaijos.
(1.) Artificial regeneration is independent of the local
occurrence of seed years, since sufficient seed for nurseries,
and frequently also for direct sowing, can always be obtained
from a distance. This being so, the adoption of the method
enables the forester to proceed in a systematic and regular
manner, doing the desired quantity of regeneration year
after year, and providing the market with a steady supply
of produce.
(2.) The full enjoyment of light can be secured at once to
young trees which are hardy.
(3.) The trees develop more rapidly than those originating
1)y natural regeneration, at any rate up to middle age.
}i. iJisddran laiips.
i\.) Sowing and planting are costly. The outlay on the
latter can, however, be considerably reduced l)y planting
small plants according to a simple and cheap melliod.
(2.) "Where artificial regeneration follows clear cutting, tlic
young plants are e.xposed to damage l)y frost, drought, insects
ARTIFICIAL VEHSUS NATURAL llEGENEKATION BY SEED. 2t)7
and weeds in a far higher degree, than if the regeneration is
conducted under a shelter-wood. In fact, tender species must
be raised in the latter way, so that for them clear cutting is
excluded. Insects frequently become formidable to coniferous
woods raised in clear cuttings, while experience has shown
them to be less dangerous to natural seedlings, especially
when these are raised under a shelter-wood.
(3.) In the case of clear cuttings, the laying bare of the
ground for a series of years may seriously affect the fertility
of the soil, so much so that the method is hardly admissible
on inferior soils.
2. Merits of Xatiiral Rrf/eiieration hi/ Seed.
((. Adraiif/ff/ffi.
(1.) Natural regeneration involves less expenditure than
sowing or planting. In some cases the outlay may be abso-
lutely nil, but in most cases some artificial help has to be
given either by working (wounding) the soil, or by sowing
and planting. Still the outlay is considerably smaller. It
must not be overlooked, however, that in the majority of
cases natural regeneration requires much time ; as long as
the shelter trees increase sufficiently in size and quality so as
to make up for any loss on this account, no harm is done,
but where this is not the case, artificial regeneration may be
actually more profitable, since no loss of increment occurs.
(2.) Damage by frost, drought, and weed growth is avoided,
or at any rate considerably reduced. The same may be said
as regards damage by insects, though perhaps not to an equal
extent.
(3.) The activity of the soil is maintained, and, to a
considerable extent, rendered independent of climatic
influences.
(4.) Owing to the greater number of plants per unit of area,
clearer and straighter stems are produced than in plantings,
and also frequently in sowings, though the difference in the
268 CHOICE OF METHOD OF FORMATION'.
latter case is lef4s decided. This adv;iiita,i;c can be nuUitied to
a considerable extent by dense planting and sowing, l)ut in
that case the cost is proportionately increased.
//. I>isinlr(iiil(i)ics.
(1.) The method is more complicated and ditttcult than
artificial regeneration ; hence it demands more skilful
foresters.
(2.) The intermittent nature of seed years produces many
drawbacks as regards the equalisation of the yield and the
control of operations.
(8.) The removal of produce is also more expensive.
3. SunnitiiKj iij).
Neither the arlilicial nor the iiutural method of regeneration
is the best at all times and under all circumstances; only a
consideration of the. local conditions can lead to a sound
decision as to which is preferable in a given case. In forming
such a decision the forester must take chiefly the following
points into consideration :—
(a.) General objects of management.
{}>.) Species to l)e grown.
{(■.) Condition of locality.
{(l.) Available funds.
{e.) Skill and capacity of the stall".
Section III. — Combination of Several Methods of
Formation.
In the preceding pages various artificial and natural
methods of forming a wood have been described. Kach of
these metliods has special advantages under certain condi-
tions. As the latter may, and frequently do, vary within a
narrow extent of area, it follows that two or even more methods
may be employed in the fornuition of a wood, thus secui'ing
greater success and fre(|uently a I'cdiictioii of cxpeiiditin'e.
COMBINATIONS OF SEVERAL METHODS. 269
In fact, in practical sj'lviculture such combinations are tlie
rule and not the exception.
Of the combinations here indicated the following are of
special interest : —
1. Combination of Artificial Formation and Natural
liefieneration by Seed.
Natural regeneration assists artificial formation only in rare
cases, but the reverse constantly happens. Natural regenera-
tions by seed rarely are so complete that they do not require
artificial help, which can be afforded by sowing or planting,
generally the latter. There are always certain parts of the
regeneration area which, for one reason or another, do not
become stocked and have to be planted up. Then it frequently
happens that the ruling species shall be mixed with others
which must be brought in artificially ; or one of the species in
a mixed wood fails to produce seed for a considerable period,
while the other, having regenerated itself, demands the removal
of the mother trees.
In many cases it can l)e foreseen that certain portions of an
area are unfit for natural regeneration ; these may be artificially
stocked at once, even before the natural regeneration of the
remainder has commenced. In other cases a part of the area
may have been deprived of the necessary shelter trees by
natural phenomena ; here artificial shelter- woods may have
to be planted.
From the above remarks it will be seen that artificial and
natural formation may be started at the same time, or the one
may precede the other. In all such cases, blanks in existing
w^oods should be filled up with strong plants of a quick growing
species.
2. Combination of Artificial Formation with Regeneration
by Stool Shoots or Suckers.
This combination occurs constantly in coppice woods, where
stools, which have died or become diseased, are replaced
270 CHOICE OF METHOD OF FORMATION.
artificially In- putting,' in stn)iiy sowing seed, such as acorns or chestnuts.
Only in rare cases are such stools replaced by natural
seedlings.
3. Combination of Xntiirdl Ilef/encration by Seed witli
Rcfjeneration by Stool Shoots and Suckers.
This case may occur in high forest, where the seedling trees
have been injured by frost, game, cattle, mice, hail, etc. ; it
may then be advisable to cut them back in order to get strong
healthy shoots.
The combination occurs further in coppice with standards.
Here it is desirable that the standards should be seedling
trees, and their regeneration may be effected by the seed
falling naturally on the ground.
4. Combination of Artificial Formation witJi Xatnral
Ilef/eneration by Seed and by Slioots.
It occurs in coppice with standards, when a sutttcient
number of the latter cannot be obtained by natural
regeneration.
271
PART III.
TENDING OF WOODS.
27:3
TENDING OF WOODS
When a wood has been established it will, if left undis-
turbed by outside influences, grow on and reach maturity ; the
individual trees will, however, enter upon a lively struggle for
existence, and the ultimate results, in the majority of cases,
will meet only to a limited extent the objects for which the
wood has been established. Moreover, external injurious
effects will make themselves felt, and further reduce the
returns. In order to realise those objects more fully, especi-
ally where a certain class of timber is desired, the growing
wood requires well-directed tending from its formation up to
the time when it is finally cut over. Care must be taken that
the most favourable conditions for growth are secured, and
that the development of the individual trees is so guided as to
produce the desired results ; in other words, the forester must
take measures to preserve the continued activity of the
locality, and to see that the wood has throughout its life a
suitable composition. The subject divides itself natural
into the following two sections : —
(1.) Preservation of the factors of the soil.
(2.) Tending the crop of growing wood.
It is not, however, intended to enter here in detail upon all
the matters which contribute to, or interfere with, the desired
result. The effects of the locality upon forest vegetation, and
vice versa, have been dealt with in Part I. of this volume,
while the protection of the soil and growing wood against
injurious influences will be dealt with in a subsequent volume
on Forest Protection. In this place only the important points
will be shortly indicated, with special reference to the sylvi-
cultural aspect of the subject.
In order that a crop may be fully productive, it is necessary
274 TENi)iN<; OF Woods.
to establish and then to preserve those physical and chemical
conditions of the soil on which a health}' and vigorous growth
depends. The means adopted in agriculture for this i)ur[)ose
are working the soil and manuring. Both are expensive, and
in sylviculture they are only feasible in cases where the
increased returns at least cover the outlay ; they are therefore
either out of tlie question, or can be employed only to a very
limited extent, and the forester must endeavour to accomplish
what is needful by other means. Fortunately timber trees
are far less exacting than field crops, so that the more modest
means at the disposal of the forester suflfice for their healthy
development.
It has been shown on page 34 that the productive power of
the soil in sylviculture depends on : —
(1.) A sufficient depth ;
(2.) A suital)Ie degree of porosity ;
(3.) ,, J, ;i moisture ;
(4.) ,, chemical composition.
For sylvicultural purposes these conditions can be procured
to a sufficient extent by the following simple agencies : —
(a.) The preservation of a suitable cover overhead ;
{b.) The preservation of the natural covering of the soil,
more especially' of humus.
How these affect the soil has been described on page 41.
The principal fact is, that the activity of tlie soil and a vigorous
development of the crop growing on it are intimately con-
nected with each other, and that one exercises a healthful
effect upon the other. At the same time the requirements of
tlie one may be opposed to those of the other, and it must be a
leading principle that the tending of the crop should always
take into consideration ii ])i(ip(u- preservation of the fertility
of the soil.
The above remarks lefer to the case of woods wliich are
fully stocked, in other words, crowded woods. Cases may
INTRODUCTORY. 275
occur, however, where it is desh-able to interrupt the leaf
canopy at a certain age so as to form open woods ; in such
cases separate steps must be taken to preserve the fertihty of
the soil.
Again, during the lirst part of the life of a wood it is subject
to special dangers, most of which disappear later on, when the
attention of the forester must be directed to other matters.
The subject may, therefore, be divided into the following
three chapters : —
Chapter I. — Tending of Woods during Early Yolth.
,, II. — Tending of Crowded Woods after Early
Youth.
,, III. — Tending of Open Woods for the Produc-
tion OF Large Timber.
T I
276
CHAPTER I.
TENDING OF WOODS DURING EARLY YOUTH.
Young woods require special protection against external
dangers until they can shift for themselves ; they must l)e
kept clean, and a proper density or composition of the crop
preserved. iVccordingly the subject will be divided into four
parts.
1. Protection tujaiiDit Kxtenial Ifaiuicrs.
The details of this subject will be found under Forest
Protection. For the present pur])oso the following notes will
suffice.
a. Fire.
Although woods require protection against lire at all i)eriods
of their life, it is specially necessary during early youth.
Protection is atiorded by removing all intiammable matter, or
clearing lire traces around the area and at suitable intervals
in the interior.
In addition, the area must be watched, so that any tires
which occur may be promptly extinguished.
l>. Fras/ (ind Ih-aiijlhl.
\\here regeneration takes place, whether naturally or
artificially, under a shelter-wood, the latter provides the
necessary protection against frost and drought, or, at any
rate, insures a considerable reduction of the danger in either
case. In cultivating cleared areas, shelter for tender species
must be artificially provided by growing simultaneously, or
beforehand, a special shelter-wood, or nurses. The trees
selected for this purpose must be frost-hardy and possess a
thin, or moderately dense crown. The best nurses in tem-
perate Europe are birch. Scotch pine, and larch. Where
EXTERNAL DANGERS. 277
danger fi-oiii late frost is excessive, larcli, owing to its early
sprouting, is less well adapted as a nurse, l)ut it does very
well in all other localities. In moist localities alder and
willows have been similarly used.
The nurses may be distributed evenly over the area, or
placed in alternate lines. They are removed when the tender
species can do without them. Frequently some of the nurses
are retained so as to form a mixed wood.
r. Cold Winds.
The effects of raw, cold winds are often more disastrous
than frost produced locally by radiation. Where they are to
be feared, lateral as well as vertical shelter is required. This
may be given either by adjoining woods of sufticient height
and density, or, in their absence, by artificial shelter belts, or
wind breaks. These must be dense, and they should be
established some time before the area to be protected is placed
under cultivation or regeneration. The species of which wind
breaks consist should if possible be evergreen, and with dense
crowns coming close to the ground, such as spruce.
All alternative measure consists in mixing a hardy species,
such as Scotch pine, with a tender crop. Or the wood is
treated under the selection system, when trees of all ages are
intermixed on the same area. In that case, the middle aged
and younger trees provide lateral shelter for the young growth,
while the old trees give vertical shelter.
In all these cases it is essential that the edges of the wood,
towards the side whence cold winds blow, should always be
kept as dense as possible.
What has been said above applies not only to frost, but also
to drought, more especially in tropical climates, \yhere hot,
dry winds may be even more disastrous than cold winds are
in higher latitudes.
d. Weeds.
In the case of the shelter- wood systems, under regular and
successful management, noxious weeds and objectionable
ilS TEN1>IN(; OF WOODS DTRING EAHI.Y YOT'TH.
species of trees are kept .sufiiciently in check to enalde tlie
young tree growth to make its way up through them. If tliis
is not the case, and in the cultivation of cleared areas, noxious
weeds must be removed wherever they threaten to choke the
young plants, until the latter have reached a sufficient height
to hold their own. Heather, broom, brambles, climbing plants,
l)irch, sallow, etc., may become even more dangerous than
ordinar}' grasses and weeds.
In considering the degree to wliich noxious plants require
to be cleared awaj', it must be remembered that in moderation
they may act beneficially, by sheltering the very young trees ;
hence interference is not called foi- until they actually become
noxious.
r. /iisrr/s (I ml FiiDiji.
These form standing dangers to woods througliout life,
especially where coniferous trees are growMi over extensive
areas. The measures whicli should be adopted to protect
forests against them are taught in Forest Protection. Several
species of both insects and fungi are specially dangerous to
young forest plants. It is the duty of the forester to watch
carefully his regeneration areas, and to destroy all injurious
insects as soon as they appear, so as to prevent the spreading
of the evil. In many cases it is necessary to let areas lie
fallow for a few years, until insects, which breed in the stools
and the refuse of the old wood, have disappeared again. As
an illustration JIiflohiKs ahirth. the pine weevil, may be
mentioned, which frequently becomes disastrous to young
Scotch jiine and spruce woods. In the case of attacks by
fungi, the diseased plants should lie removed and destroyed
as speedily as possible.
2. Prcsrrratioii of y lemoving
the lower branches the vigoui- in tlie upper part may l>e
restored. This case applies specially to oak standards, the
boles of which, exposed to light after a prolonged crowded
position, have developed epicormic l)ranclies.
2. Daiiticra cimncricd icitli Pnnniui.
The removal of dry branches or remnants of hranches is
not, as a rule, conducive to any danger to the life or heallh of
the tree, provided the operation be carried out in a careful way.
On the contrary, it often reduces the danger from rot, because
it facilitates the process of occlusion, or covering over of the
wound by layers of new wood.
Matters are different in the case of green brandies. Here the
wound caused by the removal of the branch frequently causes
rot, because the unprotected open wound offers a tit germinat-
ing bed for the spores (jf fungi ; the wound, on drying, opens
out in rents and cracks, into which rain water may carry the
spores ; the latter germinate and cause decomposition, which
spreads and reduces the value of the stem, or may entirely
destroy it. Several dangerous parasitic and saprophitic species
of fungi thus enter trees.
PRUNING. 285
It is essential, therefore, that the wound should be closed as
quickly as possible and made impermeable to the spores of
fungi and to water. This is effected liy nature through the
process of occlusion, provided the wound does not exceed a
certain size. The time required for this operation depends on
the size of the wound, the vigour of the tree, the manner in
which the wound is made, and above all the species.
Pruning green branches is least dangerous and objectionable
in the case of oak and most conifers which are in vigorous
health, provided the operation is carefully done and the wound
does not exceed 3 inches in diameter. Oak closes the wound
rapidly by occlusion, while wounds on conifers exude turpen-
tine, which protects them to a considerable extent.
As regards other European species the evidence is at present
conflicting. Pruning green branches of poplars, birch and
willows is undesirable, because their wood is liable to rot
quickly. According to Hess some of the important species
may be arranged in the following descending series in respect
of the activity of occlusion : — Broad leaved speeiea : Oak,
beech, hornbeam, lime, ash, maple, birch. Conifers : larch,
silver lir, Scotch pine, spruce. In the case of the last-
mentioned species the pruning away of green branches is,
in the opinion of most foresters, altogether undesirable.
Under any circumstances, the pruning of green branches
should not be undertaken without due consideration of the
advantages which are likely to be realised and the dis-
advantages connected with the operation; this is of special
importance in all cases where the objects of management
centre in the production of large sized timber, which can only
be obtained by permitting the trees to grow and increase for
many years after the pruning has been carried out.
3. Execution of Pruning.
Where the object is to produce valuable timber trees, the
branches should in all cases be cut off close to the main stem,
but without injuring the bark of the latter ; only in this way
286 TENDING OF CROWDED WOODS AFTER EARLY YOUTH.
can quick occlusion of the wound be expected. If the object
be merely to relieve yount; growth of cover overhead, the
above rule may lie neglected.
The work may be done with the knife, hatchet, billhook,
shears, or saw. Cutting instruments produce a smoother
surface of the wound, but, unless very carefully handled,
injuries to the bark of the main stem are likely to occur.
The saw [)i-oduces a less smooth surface, but, if carefully
handled, it does no injury beyond the actual cut. Heavy
branches should first be cut oti' a short distance from the stem,
and then, by a second cut, the remaining stump should be
removed, to ensure the production of an even cut and to avoid
tearing the bark of the main stem.
Saws are used, either in connection with a light ladder, or
they are placed on poles. In the first case pruning can be
carried out to a considerable height. Saws placed on poles
are only effective up to a moderate height, VI to 18 feet.
Of hatchets, that constructed by Courval (Fig. 82) is speci-
ally recommended. Fig. 83 represents a pushing chisel, with
which branches can be removed up to a moderate height.
Fig. 84 is a bow-less saw, and Fig. 85 an ordinary hand saw.
Fig. 86 is a saw in the shape of a bayonet fastened on a pole,
designed by the author ; it cuts with the downward stroke.
Fig. 87 represents Aider's pruning saw, which is also fastened
to a pole. The two last mentioned are specially recommended,
where the use of a ladder is not preferred.
Wounds, which are so large that they are not likely to be
speedily closed by occlusion, must receive a waterproof cover-
ing; this is necessary even in pruning large branches of
coniferous trees.
The most suitable covering consists of a layer of coal tar,
made sufficiently fluid by an addition of oil of turpentine, and
laid on with a brush. The artificial covering will only stick
on when the sap is down ; hence, in temperate Europe the best
time for pruning is autunni and the first half of winter. Dry
branches and snags may be cut off at any time of the year.
PRUNING.
287
Fig. 82.
Fig. S3
Fig. 84.
^
Fiff. Hr
Fi- 86.
Fig. 87
288 TENDING OF CROWDED WOODS AFTER EARLY YOUTH.
provided tlie living tissue of the tree is not injured durinp; the
operation.
According to R. Hartig pruning green branches while the
tree is in sap causes a somewhat rapid decomposition of the
wood near the wound. For this reason also pruning in tlie
first lialf of winter is recommended.
Section III. — Thinning.
1. General.
One of the most important objects in the formation of a
wood is to stock the area sufficiently, so that a complete cover
overhead may be established as early as possible. This is
desirable, not only for the preservation of the soil, but also for
a i)roper development of the trees. In order t) ensure quick
closing overhead it is necessary to bring on to the ground a
much larger number of plants than can find room on it for
any prolonged period. Soon after a complete leaf canopy has
been "established, the trees commence pressing one against the
other, there is not enough growing space for all, and then a
stri(;/(ile for existe)ice sets in. A portion of the trees outgrow
the rest, and they rear their heads up to the full enjoyment
of the light. Between and below them are the rest of the
trees ; some of these still enjoy with their leading shoots light
from above, though they are already dominated trees ; others
have been already left behind to such an extent that they are
actually dei)rived of the direct enjoyment of light, in other words
they are suppressed ; they live on for a shorter or longer period
according to species and other circumstances, and then die.
Thus there are four classes of trees, namely : —
(1.) Dominating trees.
(2.) Dominated trees.
(3.) Suppressed trees.
(4.) Dead and dying trees.
This struggle, if not interfered with, continues whilst height
growth lasts, and it gradually reduces the growing space of
each dominating tree to such an extent, that the hitter cannot
THINNING. 289
develop in the most advantageous manner ; consequently such
trees are likely to assume a thin, lanky shape, so that they
are frequently unable to stand upright, if deprived of the
support of their immediate neighbours. They are liable to be
])ent and broken by wind, snow, or rime. To obviate such a
state of affairs the forester interferes in good time by removing
a portion of the trees ; he tit ins the wood. Thinnings, then,
are cuttings, which have for their object to provide for each
tree left standing that growing space, which is best suited for
its further development according to the objects of manage-
ment. It is necessary to exj^lain this somewhat in detail.
2. TJtc most suitable Groiiing Space.
As the objects of management differ, so must the most
suitable growing space. A})art from this the growing space
differs according to the age of the wood, the species, the soil,
elevation and aspect of the localit3\
a. Objects of Management.
A tree growing in a free position, in complete enjoyment of
vertical and lateral light, will develop a full crown and root
system, and lay on a maximum of volume. This is no doubt
a great point, but it is counterbalanced by serious drawbacks : —
In the first place a wood grown in this fashion does by no
means always produce the greatest volume per acre, as the
total production is represented by the average volume per
tree multiplied by the number of trees per acre. Although
each tree in a crowded wood has a smaller volume than one
grown isolated, yet, owing to the greater number of trees per
acre, a crowded wood may have, and generally has, a greater
total volume per acre than one in which the trees grow
isolated. Secondly, isolated trees are liable to suffer in height
growth and in straightness. In the third place, such trees are
frequently covered with branches low down, and in consequence
they produce less valuable timber. In the case of conifers the
timber is also liable to be of an inferior quality, owing to the
greater breadth of the concentric rings. Last, but not least,
•2t>() TENDIN(; OF CHOWDKl) WOODS AFTKU KAlUA' YOUTH.
open woods cannot preserve the fertility of the locaHty ; hence
they are only admissible on fertile localities, or special
measures must be taken to preserve the fertility of the soil.
These considerations govern the most profitable growing
space in any particular case. It is conceivable tliat under
certain condilions tlie con-f^ct policy is to i-cniove all dead,
suppressed, and dominated trees, and even a portion of the
dominating trees, while in others the dominated and even
suppressed trees may have to be carefully husbanded, so as to
realise the objects of management in the highest possible degree.
Ii. A I It' I if Wood
As the number of trees per acre decreases gradually from
several thousands to a comparativel}' small number at maturity,
it follows that the growing space increases with advancing
age, though not evenly. Statistics collected on this point in
Germany gave the following results foi- pure woods of Scotch
pine, spruce and beech, grown on soils of lirst quality : —
Age of Wood, ill
yeai-s.
Numbei- of Trees,
pel- .acre.
Mean Orowiiig
Space per Tree,
in square feet.
Decrease in the
Number of Trees
during 20 Years.
Increase of Grow
ing Si»ce i«r
Tree, iu per Cent.
L.ScofrhPini':
20
40
1.420
720
80)
(10 J
700
100
(id
870
)
llSj
8.-.0
'J 7
S(l
280
)
IS'.tj
140
60
Kin
170
1
2.-.G)
l°>()
8.-.
11. S,>r,rr:
■JO
LI 80
l.->|
8!)/
1.840
100
(10
510
)
8^1
(•.20
118
.SO
810
14l|
200
(u;
100
220
l'..S)
•.)o
40
111. JWr/,:
20
4(1
2,:.:)0
'.MO
4(;i
Fcio
171
CO
428
1
108,
.-.17
124
SO
24'.)
1
1 7', i
171
70
100
l('>(i
2«2/
88
r.o
THE MOST SUITABLE GROWING SPACE. 291
These data show that :
(1.) The increased requirement of space is very great
between the ages of 20 and 40 years; it then falls
gradually up to the age of 100 years.
(2.) Many trees must be removed during the earlier part of
a wood's life, and comparatively few later on, always
assuming that the area is to remain fully stocked.
r. Speries.
Light demanding species require more space than shade
bearers ; broad-leaved species more than conifers.
The above table shows that the light demanding Scotch pine
requires considerably more growing space than the shade
bearing spruce ; the latter less than the still greater shade
bearer the beech.
Comparing the growing space of Scotch pine, larch, oak,
and birch with that of spruce, beech, and silver fir, the pro-
portion is about 100 to 65.
: Allitude.
Under otherwise equal conditions the number of trees per
acre increases with altitude, at any rate up to a certain eleva-
tion. The statistics of the Black Forest for the three regions
approximately indicated as below 1,200, 1,200 — 2,100, and
2,400 — 3,600 feet, showed the following proportion in the
number of trees : — 100, 126, 244, This law could not be
established above 3,600 feet, because at that height regular
woods disappeared. It was farther noticed that the difference
is more pronounced in the case of shade bearing species and
u 2
^02 TENDING OF CROWDKl) WOODS AFTKU EARLY YOUTH.
during the earlier part of life, tliaii in the case of li^^ht
demanding species and latei" on in life.
/'. .\s/ic< Thnhcr.
Where the production of high-class timber is aimed at,
quantity must to some extent be sacrificed. Trees fit to yield
such timber must answer the following description : —
(1.) The boles must be tall, straight, free of branches, and
as litt'e tapering as possible.
(2.) Differences in the breadth of the concentric rings must
be slight.
(3.) The timber must have a high degree of density.
Boles free from branches and non-tapei'ing are not produced,
if heavy thinnings are made at an early age of the wood ; at
any rate not in the same degree as if the wood were kept
dense, when the lower branches are more rapidly killed for
want of light. Pruning cannot make up for this, though it
can do something.
There is naturally a tendency to produce broader rings
during youth than later on ; heavy thinning at an early age
29(\ TENDING OF CROWDED WOODS AFTER EAUEY YOUTH.
increases the ilitYerence, leading to the formation of trunks
whicli consist of a niimher of broad rin^^'s in the inner i)art,
surroinided by a series of narrow ones. Such timber is for
many purposes of smaller value than if the rings are of
uniform breadth throughout.
As regards the density of the timber, a distinction must be
made between the various species. In the case of those broad
leaved species which have the pores in the spring portion of
the wood, broad rings indicate high density, and narrow rings
comparatively low density ; here, then, heav^y thinnings are
indicated. The same prol)ably holds good for species which
have the pores uniformly distributed over the ring. In coni-
fers, however, the matter is reversed, as in their case broad
rings usually represent low density and narrow rings high
density ; consequently heavy thinnings must be avoided, at
any rate up to a certain age.
On the whole it may be said that, in the production of
higli-class timber, heavy thinnings at an early age should be
avoided. The rule here, according to which the thinnings
are to be made, must run as follows : —
The wood sliould be thinned lightly until towards the end
of the principal height growth. Then the thinnings should
gradually become heavier, so as to assist a selected number
of trees by the gradual removal of all those which are inferior
and diseased ; in other words, the thinning is then done more
in the dominating and dominated trees than in those which
have been left behind in the struggle for existence and no
longer compete ; the latter, if capable of living on, may be left
to assist in the protection of the soil or to act as wind brakes.
This method of thinning is called " eclaircie par le haut "
in French, and " Hochdurchforstung " in German.
4. TJiiintiiKi of Mixed ll^oods.
In the foregoing pages the theory of thinning as applicaljle
to pure woods has been given. Generally, the points aimed
at are to stimulate producticm and to develop the most suitable
THINNING OF MIXED WOODS. 297
individuals for the final crop. In mixed woods a third con-
sideration iDresents' itself in the preservation of a suitable
mixture without interfering with the maintenance of a sufficient
leaf canopy ; this often leads to deviations from the theory as
indicated above.
In the case of mixed woods it may often be necessary to
remove a dominating tree of one species, because it threatens
to suppress a tree of another species, which must be preserved
for the sake of the mixture. To guard against an interruption
of the cover in such cases the dominated and even suppressed
trees must be more carefully husbanded than in pure woods,
until, with the advancing age of the wood, the mixture has
l)een secured. Frequent and light thinnings are in such
cases indicated. Their actual degree depends much on the
light requirements of the more valuable species in mixture.
The operation is facilitated if the several species are mixed by
groups instead of by alternating single trees.
Where a valuable timber species is mixed with a less
valuable one, the former must be favoured from an early age,
so as to bring it to the highest possible development, if neces-
sary at the expense of the less valuable species. As long as
the valuable species is of quicker growth than the other, the
operation is comparatively simple ; but if it is of slower growth,
all individuals of the secondary species which threaten to over-
top it must be cut away, until the principal species is secure.
5. Tliinniiig of Coppice Woods.
These thinnings are conducted according to the same
principles as in high forest, whenever the number of shoots
is so great that there is not enough growing space for all.
More especially in oak coppice the quality and quantity of
bark may be considerably influenced by leaving on each stool
only the two or three best shoots and removing the others.
Such thinnings are generally made in the second half of the
rotation. In coppice with standards, such thinnings are
frequently required to set free seedling plants growing
amongst the coppice.
:2V' s TENDING (»F CROWDED WOODS AFTER EARLY YOUTH.
tl. Principal Adnitttafics of Thinninfis.
The principal advantages of thiDiiings are as follows: —
(a.) They afford the means of guiding the development of a
wood in accordance with the objects of management,
either by producing the iireatest possible quantity, or
the best possible quality of produce ; in some cases
l>oth these objects may be combined.
(b.> They afford the means of preserving a suitable mixture
in the case of mixed woods,
(c.) Danger from insects, fungi, and fire is greatly reduced
by the prompt removal of dead and sick trees,
(d.) They afford the means of strengthening the trees
destined for the final crop against damage by snow,
rime and wind,
(e.) They yield substantial early returns.
The returns from thinnings should not be under-estimated,
especially where the object of management centres in the
production of quantity. According to the yield tables of Weise,
Scotch pine may be expected to yield the following returns
under a rotation of 100 vears : —
Quality Cla^ of Locality.
ri'H-:-> JE s:.".:i: cubic fe#t perj
Intermediate
Retoms, or Final BeTorii*.
Thinnins*.
oTInto--
Tw^li^t^ to
Final !
Total. B*ain»*, in n
WT C*nt.
A.—rtmher and Fagots.
I„ or best
II., or middling
III., or worst .
. ^ 4..>80
2.4 7««
III
.^2
41
17
B.—
r,mber of 3 infhc*
diametrr ami
Kptrard* ami if.
I
n
Ill
3,370
1,820
250
8.130
5.330
2.420
11.300
7.15f»
2.670
41
34
11
Similar infoimation regarding the yield of thinnings in
spruce, silver fir and beech woods will be foimd in Volume III.
EXECUTION OF THINNINGS. 299
7. Exeaition of Thiuninfis.
The advantages of thinnings can l)e fully realised only if
the operations are conducted in a careful and judicious
manner ; in other words they must he attended to by a
competent forester and not left to the wood-cutters.
In young woods, which have as yet a large number of trees
per acre, thinnings should generally be carried out in the
presence of a competent forester ; only where the wood is
absolutely uniform throughout, a sample may be prepared as
a guidance for the workmen, and this only if the latter are
thoroughly reliable and competent. In the more advanced
stages of life each tree to be removed should be marked
separately and in the forester's presence, and this should be
done while the trees are in leaf, so that the effect of the
removal may be properly judged. Special care is necessary
where valuable timber trees are to be produced, where domi-
nating trees are to be removed, and where a proper mixture
of species is to be preserved.
The exposed edges of a wood should be thinned heavily
from an early age onward, so that the remaining trees may
retain their lower branches, and thus be trained to withstand
strong winds. If the wood be subject to the effects of raw,
cold, or dry, hot winds, the exposed edge should be kept as
dense as possible, and an additional strip some distance from
it may be kept in a similar condition.
The best time for the execution of thinnings is winter, but
local circumstances demand deviations from this rule. In
high mountains they must be done in summer, as the localities
are generally inaccessible during winter.
;i(i()
('RAPTKK III.
TENDING OF OPEN WOODS FOR THE PRODUCTION
OF LARGE TIMBER.
1. Thr Theori/.
In the foregoing chapter it lias been shown how thinnings
should he conducted, if the principal part of a wood — the
dominating trees — are to be given increased space and enjoy-
ment of light, followed by increased increment, without, how-
ever, interrupting the leaf canopy to such an extent as to
affect injuriously the continued activity of the soil. Under
this method of treatment the one aim acts antagonistically to
the other, and it is by no meanf^ easy to conciliate the two
interests. Hence the problem presents itself, whether the
better portion of the dominating trees cannot be more com-
pletely isolated, while the soil is protected by other means.
There are other considerations whicli press the subject upon
the attention of the forester. Under the ordinary system, as
described above, the production of large sized timber demands
a higli rotation, and any measures which tend to reduce tlie
latter must be welcome. Experience has shown that by
isolating the trees, timber of a certain size can be produced in
little more than half the time required under tlie method of
continuously crowded woods.
Anotiier point is, that man}', and more especially the light
demanding, species have a natural tendency to open out, or to
form large crowns.
It is of additional importance that under a system of heavy
thiimings, considerably larger intermediate yields are obtained
early in the rotation. This, in conjunction with the more
rapid development of the trees constituting llic liiial cio]).
leads to more favourable Ihiancial results.
THE THEORY. 301
On the other hand, the early isolation of a portion of the
trees has weighty drawhacks. In the case of many species it
affects injuriously the height growth of the trees. Then,
isolated trees maintain their side branches low^ down, and even
develop fresh ones, which for many purposes seriously reduce
the value of the stems. In the case of conifers the quality
of timber also may be lower, owung to the formation of
exceptionally broad concentric rings. Isolated trees are
further liable to form more tapering boles than those grown in
crowded woods. Above all, in the majority of cases a suffi-
cient layer of humus cannot be preserved, its place being taken
by weeds. Moreover, a suital^ie degree of moisture cannot be
maintained. It follows that, except on really fertile soils,
other means must be devised to preserve the continued
activity of the soil. This is done by the introduction of an
underwood, or soil protection wood. But even then it is
found that the extra diameter increment, laid on after isolating
the trees, will hold out only on soils of some quality, while on
indifferent soils it will, after a few years, sink back to its
previous amount.
The general theory of the method of treatment in the case
under consideration may be shortly described as follows : —
Commencing with the first thinnings the most promising
trees are singled out, and these are isolated sufficiently by
increasingly heavy thinnings, so as to permit the introduction
of an underwood. As soon as the latter has established itself,
and is capable of protecting the soil, a further heavy thinning
is made, by which the remaining trees are completely isolated.
Subsequently more thinnings follow, as required by the
extension of the crowns of the trees.
The underwood can be established in a variety of ways,
such as by sowing or planting, by natural seeding, or by
coppicing a portion of the overwood. In some cases the
underwood itself is allowed to grow into timber trees (two-
storied high forest) ; in others it remains a soil protection
wood.
802 TENDIXr, OF OPEN WOODS FOR LARGE TIMBER.
The pnx'cdure differs coiisideral)!}' according to species and
the ol)jects of management. To meet the special requirements
of each case a considerahle numher of modifications have been
ehiborated. Some of these commence with tlie isohition in
early growth, while others during the greater part of the
rotation follow the system described in the last chapter, and
reserve to its latter part the isolation of the more valuable
trees.
Although the treatment has been recommended for almost
all species, it is eas\' to perceive that thinly crowned species,
which are generally light demanding, are better adapted for
the method than those with a dense crown, as the underwood
has a better chance of thriving under the former, and doing
justice to the task which it is called upon to perform. In
Britain the oak, larch, and Scotch pine have, in a rough way,
been treated according to this method for a long time past.
On the Continent the treatment has been elaborated in
comparatively recent times.
2. I'riiicijial Foniis . Isdhttidii of a fi'ir Srlirlnl Tiers, irilhoiif C inlcnroinl.
A limited number of selected trees are placed in a free
position, by removing all surrounding trees which threaten to
interfere with them. The system should be applied only in
case the nuiin part of the wood consists of a species with full
crowns, and where the selected trees are of (juicker height
growth than the rest.
To avoid loss of height growth and the retention of low side
bi-iuiches, the operation sliould not be commenced until
towards the end of the period of principal height growth.
The treatment is specially adapted to mixed woods of beech
and light deniaiidiiig broad leaved s[)ecies, such as oak. ash,
and elm.
PRINCIPAL FORMS OF TREATMENT. 303
b. Prolongatiiiii of the Ratjeiipratioa Period under the
Shelter-wood Systems.
Woods treated under artificial or natural regeneration under
a shelter-wood offer excellent opportunities for the realisation
of the extra increment due to an isolated position of a limited
number of trees. In the same degree as the shelter-wood is
thinned out by successive cuttings, the remaining trees profit
by accelerated increment ; the process can be further extended
by retaining a limited number of trees for an extra term of
years, or by prolonging the regeneration period.
The method is specially adapted to thin crowned, wind firm
trees. Shallow rooted trees are likely to be thrown by wind.
The injurious effect of trees with crowns coming low down
upon the young growth must be mitigated by pruning away
their lower branches.
c. lletention of Standards in Hiyh Forest.
A limited number of the most suitable trees are, after the
wood has been regenerated, retained as standards for part or
the whole of the second rotation, and in some cases even for
a third rotation. Only wind firm species are thoroughly
suited for such treatment, and they should moreover be thin
crowned. The number of standards depends on the density
of their crown and the quality of the soil ; only perfectly
healthy well-formed trees should be chosen, especially those
which have cleared themselves of branches to some height, to
obviate the necessity of pruning. The tending of the proposed
standards may usefully be commenced some time before the
end of the first rotation, as indicated under a.
d. Isolation of Trees in Conjunction a-ith an Underwood.
A wood is uniformly thinned, and an underwood is formed
by sowing, planting, natural seeding, or by coppicing a portion
of the overwood. Thoroughly satisfactory results are obtained
only if the overwood consists of thin crowned and the
y04 tp:ni)Ing of open avoods for lai{(;k timrkk.
underwood of shade beurinj]; species. In temperate Europe,
oak, ash, ehn, hirch, and Scotch i)ine are the species specially
suited for the overwood, and beech, hornbeam, silver iir,
spruce, and in some cases Douglas fir, Weymouth i)ine, sweet
chestnut and hazel for the underwood. Sometimes the under-
wood is itself allowed to grow up into trees ; in other cases,
when consisting of broad leaved species, it is treated only as a
soil protection wood, and is periodically coppiced. Beech
makes the best underwood, as it bears much shade and
improves the soil more than any other species. Silver fir
comes near it. Hornbeam is best in frost localities. Spruce
should be used only in fresh localities, as on dry soil it may
cause the overwood to fall off in growth.
Where the underwood is permitted to attain the size of
timber trees, it is cut with the overwood ; the latter may, how-
ever, ])e retained for two rotations of tlie underwood, thus
producing specially large timber.
A few remarks on the tending of the more important species
will further illustrate the method.
i. Oak as OvEiiwodi).
A fully stocked oak wood is, when the projter time has
arrived, thinned rather heavily at frequent intervals, say
every 5 to 10 years, according to the locality ; during these
operations all trees with a tendency to lag behind are removed,
as well as ill-shapen and diseased trees. At the age of 30 to
60 years, according to circumstances, a specially heavy
thinning is made and the underwood started, beech being best
for the pur])ose. When the underwood has established itself,
say 10 to 15 years afterwards, another heavy thinning is
made, by which the remaining trees are isolated. Subse-
quently more thinnings follow, at moderate intervals, in the
same degree, as the oaks develo}) and llireaten to close up
again.
It is estimated tiuit in this way about 50 oak trees per
acre can be made to reach a diameter in 120 vears, which
THE IMPORTANT SPECIES. 305
in a fully stocked wood they would reach in about 200
years.
ii. Lakch as Ovekwood.
This being a quicker growing and shorter lived tree than
oak, the first specially heavy thinning and underplanting may
be done between the 15th and 30th year. The underwood
should consist of beech. Silver fir is also recommended, but
it grows slowly during the early part of its life. Another
species suitable for underplanting may be found in the
Douglas fir. Possibly Weymouth pine may answer. The
two last-mentioned species are of quick growth.
In this manner about 75 larch trees per acre may be
brought to large timber size in 60 to 80 years.
iii. Scotch Pine as Over-wood.
The heavy thinning and underplanting may take place
between the 20th and 40th year. Beech is an excellent under-
wood, but spruce is also admissible in this case. Douglas
fir and Weymouth pine may do, where the locality is suitable.
The last-mentioned species grow so rapidly, that they will
reach timber size at the same time as the Scotch pine.
iv. Otiieii Species as Overwood.
Ash, elm and sweet chestnut may be treated in a manner
similar to that indicated for oak. Various other species, such
as spruce, silver fir and beech, either pure or mixed, have been
tried and recommended for treatment under this method, but
it would be beyond the scope of this manual to enter into a
discussion of the question, under what conditions and in how
far they are suited for the purpose.
3. Execution of tJic If^orA".
The selection of the trees for removal must be most care-
fully considered, as mistakes made in this respect are difficult
to rectify. The main point is, that almost from the first
thinning the trees likely to form the final crop are favoured
«• X
306 TENDING OF OPEN WOODS FOK LARGE TIMBER.
and trained for their ultimate purpose. They should consist
of the i>est trees which are likely to develop into line, valuable
timber trees of large size ; to enable this favoured portion of
the wood to reach such proportions in the shortest possible
time, mucli of the rest of the wood must be sacrificed. This
should not be done, unless the sacrifice is more than covered
by the special excellence of the final crop, a case which can
be expected to occur only on fairly favourable localities,
which insure a special increment of the isolated trees during a
considerable period of time.
307
PAKT IV.
SYLVICULTURAL NOTES ON BRITISH FOREST TREES.
x2
309
SYLYICULTUEAL NOTES OX BEITISH
FOREST TREES.
The theoiy and practice of sylviculture, as described in this
work, have been ilhistrated by instances taken from the more
important forest trees grown in temperate Europe. For the
sake of reference, it will be found useful to bring these scat-
tered remarks, and other information, together in a set of
notes on each of the trees which are of real sylvicultural
importance in Great Britain and Ireland.
The trees naturally arrange themselves into two groups,
the broad leaved and coniferous species. Of each group the
important shade bearers have been placed first, as the notes
on the light demanders depended on those referring to the
former. Generally, the notes have been made as short as
possible ; if a full account of each tree had been given, this
part would have attained the size of a book. Apart from the
author's own experience, they have been derived from the best
authorities.
The following explanations will be useful : —
(1.) The average specific gravity of air dried wood has
been taken from Hess's " Die Eigenschaften und das
forstliche Yerhalten der wichtigeren in Deutschland
vorkommenden Holzarten.''
(•2.) By volume increment is here understood the mean
annual production per acre in crowded woods calcu-
lated from the increment of the most favourable
rotation.
(3.) The information about insects refers principal!}- to
Britain.
8]<) NOTKS ON HIUTISH FOKKST THKKS.
1. J3bkcii — Fi si/lnitira (L.).
n. mm If.
]3eech yields excellent firewood and very good cliarcoal.
The timber is not of much vahie wliere strength and durabilit}'
are wanted ; it is brittle and short grained. Specific gravity,
air dried, on an average = "74. Under water it lasts well.
Formerly the timber was much used in machinery, especially
by millwrights ; nowadays iron has replaced it for many
purposes. Beech M'ood is still used for furniture, in carpentr}',
turnery, etc., more especially for the manufacture of chairs in
Buckinghamshire and adjoining counties. On the Continent
it is much used for packing cases, barrels, wooden shoes
(sabots) and heels of ladies' boots. It is used also for railway
sleepers, after treatment with antiseptics. The leaves are
used for litter, the nuts as fodder for pigs and deer ; the
seeds yield a superior oil. The wood is rich in potash.
//. /Ji.s/n'buliaii.
It is found in temperate Europe from Norway to the
Mediterranean, or between the 40th and GOtli degree of
latitude, also in Western Asia ; it is apparentl}' indigenous in
England, and found planted in Scotland and Ireland. It is a
tree of the lower mountains and plains ; going up to about
700 feet in Norway, 1,200 feet in Derbyshire, 4,500 feet in the
Alps, and over 0,000 feet on IMount Etna.
r. LardHli/.
Climate. — lieecli is fairly hardy as regards wiiilcr frosL l»ut
very sensitive to late sprhig frosts, wliidi. during early youth,
frequently injure or- even kill it. It stands more shade than
any other indigenous broad leaved species, but somewhat less
than silver fir. It requires a fair amount of moisture in the air,
hence it grows well in the vicinity of the sea and on northern
and eastern aspects, while it disai)pears in the eastern part of
Europe owing to the drier continental climate. It is liable to
l)e thrown by strong winds, but not to aiiv excessive extent.
THE BEECH. 311
Soil. — Beech requires a soil which is at least of middling
depth, of a moderate degree of porosity, fresh and fertile ; it
thrives best on loamy soils, and especially on marls, and on
calcareous soils generally ; also on sandy soils, provided they
are thoroughly fresh and contain water at a moderate depth
in the subsoil. Wet soils are unsuited, and inundations fatal,
to beech.
//. Sk((po and Dei'f'loimienf.
The stem of the beech divides, as a rule, only in the upper
part ; the crown remains oval until towards the end of the
principal height growth, when it becomes flat or rounded off
at the top. Owing to its shade bearing power, the crown
extends far down the stem, if grown in the open. In crowded
woods, the crown occupies about the upper third of the height
of the tree.
The root system extends to a moderate depth, the tap-root
being of no importance after the first 5 or 6 years. Beech is
of slow height growth during the first years of life, compared
with other broad leaved species ; when from 20 to 30 years
old, the rate of height growth increases, so that it outgrows
the other broad leaved indigenous species, as a rule also the
oak, reaching an ultimate height of about 110 feet, and
under specially favourable conditions considerably more. In
Normandy trees up to 170 feet high have been measured.
Spruce, silver fir, larch, Weymouth pine, and Douglas fir
attain, under ordinary conditions, a greater height than beech,
though the silver fir grows slower during early youth.
The volume increment of beech is greater than that of the
other indigenous broad leaved species, but smaller than that
of the principal conifers. According to the latest yield tables
the total production of timber and firewood in the course of
100 years, on a locality of the first quality, should be, in the
case of : —
Silver fir .
=
23890 c'
Scotch pine .
. = 18170 c'
Spruce
=
22180 „
Oak .
. = 12730 „
Beech .
. =
lo230„
:Ui NOTKS ON IWill'lSH FOREST THKES.
If grown in crowded woods, l)eecli rarely reaches an age of
more than 200 years ; in the open, it attains a much greater
age.
I'. Hi'piOihii liri' I'liirrr.
I3eech commences producing full crops of good seed at the
age of ahout 60 years; it yields heavy crops, but full masts
cannot be counted on at shorter intervals than 5 years, and
often 10 to 15 j^ears, according to local circumstances ; partial
masts occur during the intervals. Taking both factors
together, the reproduction of beech by seed is less favourable
than that of most other indigenous species.
Reproduction from the stool is feeble, as compared with
other broad leaved species ; it ceases after the age of 40 j^ears,
and the stools rarely last for more than three or four rotations ;
it is best on marls.
/. ('Iidrdclcr itiiil CoiiijXisiliiin af Wnods.
Beech is eniinenll}' adapted for growing in })ure woods,
since it shades the soil thoroughly up to an advanced age,
maintains and even improves its fertility, and bears much
sliadi . For the same reasons it is e(iually well adapted to
t'urui the principal constituent of mixed woods. Probably no
other species equals it in this respect. Trees like oak, ash,
maple, elm, silver lir, Scotch pine, larch, and also spruce
thrive best when mixed with beech ; in fact this is the case
with almost any species which thrive; on localities suitable
for beech.
//. Siilriiiilhiidl Si/slcinf<.
]3eecli is specially ada[)ted for high forest. It is less well
suited for coppice woods, owing to its feeble reproductive
power from the stool. It iip[)oars as underwood in coppice
with standards. In high forest the rotation should range
between HO and 120 years, in coppice between 20 and
35 years.
In high forest it is grown in even aged and uneven
aged woods ; lar-'e areas are treated as selection woods
THE BEECH. 'U-'i
(Buckinghamshire). It is the best species for underplantiiig
open woods of valuable timber trees.
h. Formdtioii af Woods.
Beech is specially adapted for natural regeneration by seed
under shelter-woods, if the cuttings are arranged in a suitable
manner. Direct sowing and planting can also be done, but
the young crop must be sheltered whenever late frosts and
(brought are apprehended.
The seed ripens in October, and falls shortly afterwards,
retaining its germinating power for about six months. Up to
80 or 90 per cent, have been found to germinate, but it is con-
sidered good seed if at least 50 per cent, germinate. One
pound of seed contains, on an average, about 2,000 nuts.
Direct sowings may be made in autumn, or spring ; in the
former case the seeds are liable to attacks by animals, and
the seedlings, owing to their early sprouting, to damage by
spring frosts ; in the latter case the nuts must be kept in an
airy place or shed, and turned over periodically (during dry
weather towards spring it may be slightly sprinkled with
water to prevent drying up). If sown in spring, the nuts
sprout after four to six weeks. About 150 pounds of seed
per acre are required for broad-cast sowings, and propor-
tionally less for partial sowings. The nuts receive a covering
of three-quarters of an inch on soil of middling density, some-
what more on loose and a little less on heavy soil.
In nurseries, the seed is generally sown in drills. The seed-
lings may be left in the seed bed for two .years, when they
are pricked out in lines, the latter being from 12 to 24 inches
apart, and the plants in the lines from 4 to 8 inches. When the
plants have stood two years in the lines, being then altogether
four years old, they are ready for putting out into the forest.
They are usually planted in pits from 3 to 4 feet apart. For
underplanting, two years old seedlings are frequently used. As
a general rule, the seedlings and young plants require protection
in the nursery against frost as well as against hot sun.
:i\4- NOTES ON HHITISII I'OHEST TltKKS.
It is not desirable to prune beecli plants.
The process of natural regeneration under a shelter-wood is,
on the whole, slow ; one or more preparatory cuttings are
required, and if the soil be not sufficiently prepared at the
advent of a seed year, it must be worked (wounded) ; this
is best done by light hoeing ; the seeding cutting is compara-
tively light, and the cuttings in the final stage are regulated by
the character of the locality and the requirements of the
young crop. Under favourable circumstances the whole
regeneration period may be completed in 10 years, but
frequently extends to 20 years and even more.
i. TcntJiiKj.
Fertiliiii of the Soil. — Fully stocked beech woods preserve
and even improve the fertility of the soil to a greater extent
tlian any other species, owing to their dense foliage up to an
advanced age, and the heavy fall of leaves.
External Dangers. — Late frosts are the greatest enemy
of beech ; during early youth they kill or seriously damage
the plants, and even later on the tender parts of the tree
are liable to suffer ; hence it must be raised under shelter,
which is provided either by the old crop, or by a special
shelter- wood of hardy species, such as Scotch pine, birch, and
larch ; Austrian pine will also do. In natural regenerations,
the edges of the shelter-wood must be kept as dense as pos-
sible to afford protection against cold winds. In tlic culti-
vation of blanks, artificial shelter belts must be grown some
years beforehand, on the side whence the cold winds l)low.
]3eech suffers also from drought while young. Later on it
is more than any other species exposed to blistering of the
bark by the sun ; the bark is also separated from the wood, if
struck by the morning sun after a heavy niglil frost ; hence it
is not well suited for standards, apart t'roiu (lie heavy cover
which the tree gives.
Storms, snow and rime are (mly to a limited extent liiiilful
in l)eech woods.
THE HORNBEAM. 3L5
Cattle and game like to browse beecli ; red deer, hares,
rabbits and mice peel off the bark. Insects rarely do much
damage. The leaves are devoured by lepidopterous larvse,
especially those of DasycJiira pndibunda, and HaJias j^rasinaiia,
and sometimes the polyphagous Llparis monaclia, as well as
by the weevil Orchestes fagi. An ajDhis, Cri/ptocorcus faiji,
sometimes kills old trees. The freshly cut timber is liable
to the attacks of Tomicidte, and other boring beetles.
Of fungi, Pliytophtliora omnivora destroys young seedlings ;
where it appears in large quantities, seedlings cannot be
raised for 5 to 8 years, hence nurseries must be changed,
or used for other species. Nectria ditissima causes canker on
the stem, which may, however, also be the consequence of
frost. The so-called green rot is due to Peziza ceruginosa.
Priuiiitg.— Beech stands pruning better than most other
species, but it is rarely, if ever, done unless the shade injures
other more valuable timber trees.
Thinnings are commenced at the age of 25 to 40 years,
according to locality ; they should be at first moderate, after-
wards heavy.
2. Hornbeam — Carpiniis Befulus (L.).
a. Ufili///.
The hard and heavy wood is an excellent fuel, and it yields
good charcoal. The timber is very tough, and is used in
machinery by the millwright, for wheels, and a variety of
other purposes. Specific gravity of air dried wood = "75.
The ashes are rich in potash. The leaves yield good fodder.
I). Distribution.
It is found in temperate Europe up to the 60th degree
of latitude. Indigenous in England ; planted in Scotland and
Ireland. Goes up to 1,200 feet in the Harz Mountains, and
to about 3,000 feet in the Alps ; generally a tree of the low
lands and low hills.
.'316 NOTES ON RHITISH I'OHKST THKKS.
r. LoikUIij.
Cliiiuitr. — The hornbeam requires only a moderate tempera-
ture, and thrives even in cold moist localities unsuited for
beech. It is one of the most frost hardy species, hut rather
tender as regards summer heat. It stands a considerable
amount of shade, but not so much as beech.
It seems to require a moderately moist atmosphere, and
prefers north and east aspects. It is to some extent lial)le to
be thrown by wind, but resists snow uiul rime ratliei' well.
Soil. — Hornbeam likes a soil which is somewhat loose, of at
least middling depth, thoroughl}' fresh if not moist, and
minerally rich. As regards moisture, it stands between beech
and ash, and in respect of mineral matter in the soil it is not
quite so exacting as beech. Loams, sandy soils rich in liunnis,
and marls suit it best ; here it attains its full development. At
the same time it is found on dry soils, though of inferior
development, and on heavy clay soils ; it frequently replaces
beech in heavy soils and in frost localities.
(/. S//{i/)e ami hcrflo/nnriil.
The stem of the hornbtuini is generally divided into branches
comparatively low down. The general shape of the tree, if
grown in a favourable locality, approaches that of the beech ;
on inferior soils it sinks down to an insigniticant tree, witli a
short bole and large crown. The root system on the whole is
not deep going ; there are strong side roots which reach a
moderate depth.
It grows somewhat quicker than beech during the Ihst
years of life, but it rarely reaches a total height of more than
75 feet.
Its volume inerement is considerably smaller than that of
beech ; nor is hoinbeani so long lived as the latter.
f. Urinodiiclirr I'dii'cr.
Hoinbeani commences beai'ing full crojjs of seed when
about -10 years old, and it seeds plentifully almost every year.
THE HORNBEAM. 317
at any rate every other 3'ear, so that its power of reproduction
by seed is on the whole great.
The reproduction from the stool is excellent ; the shoots
appear at any part which has been coppiced. The stools last for
hundreds of years ; the tree is eminently suited for pollarding.
/. Clutrarh'T (ind Coiii/wsifio/i. of Woo/Is.
Hornbeam appears in pure woods in Eastern Europe, and
also in England (Epping Forest). It is not equal to beech in
its capacity for improving the fertility of the soil, since it has
a lighter foliage, does not maintain a cover overhead so long,
and does not bear so much shade ; the leaves also decompose
more rapidly than those of beech. At the same time, it stands
next to beech in this respect amongst broad leaved species, and
may replace it in localities unsuited for beech.
Hornbeam appears chiefly in mixture with beech and oak,
but also, like the beech, with other species, but not to the
same extent.
//. Sijlvkiiltaral SijstemH.
Hornbeam can be grown as high forest, coppice, or pollards.
It appears as underwood in coppice with standards, and makes
an excellent soil protection wood in open woods of valuable
timber trees. It also makes excellent hedges.
As high forest, it would generally be treated under a
rotation not exceeding 100 years, as coppice from 15 to 35
years, and as pollards from 5 to 10 years.
It. FortiK/fio/i of Woo(/)i.
Hornbeam can be sown, planted, or naturally regenerated ;
the latter is a suitable method. Sowings and plantings do
not require shelter.
The seed ripens in October, and falls from that time until
towards spring ; it keeps its germinating power for two or
three years ; up to 80 per cent, are capable of germinating ; it
is good seed if 65 per cent, germinate. One pound contains
on an average about 15,000 clean seeds without wings.
818 NOTES ON BRITISH FOREST TREES.
The seed germinates only in the second spring, that is to
say about eighteen months after ripening. The best treat-
ment consists in bedding it mixed with sand in a ditch,
stirring it from time to time, and sowing it in the spring
of the second year. About 35 pounds of seed per acre are
required for broadcast sowings ; it requires a covering of about
^ to f of an inch.
In nurseries the seed should be sown in drills ; the
seedlings may be pricked out when one year old. Plantings
are done with plants three years old and upwards, the plants
being put about 4 feet apart. They stand pruning well.
The tree can also be propagated by cuttings, Avhich may l)e
several feet long ; the latter method may ])e employed for
hedges. In regenerating hornbeam naturally by seed, the
seeding cutting is mucli heavier than for beech, while the
remaining shelter-wood may be removed much more rapidly,
owing to the hardy nature of the tree.
/'. Teiidhitj.
Hornljeam is well adapted to maintain the fertility of the
soil, but not to the same extent as beech. It is little
threatened by external dangers ; the tree is frost hardy, but
during youth liable to suffer from continued drought. Inun-
dations affect it little. Game and cattle browse the leaves, and
mice peel the bark, which is also sometimes done by red deer.
The damage heals, however, quickly.
The hornbeam rarely suffers from insect attacks. The
species infesting it are much the same as those of the beech.
In addition, the larva) of the Winter moth, Chcimatohia
l)nim(it((, strip the hornbeam of its young leaves.
Fiouji : — KxoascHs rarj)iiii produces witch's broom ; canker
on stems and branches is produced either by Xectria (Utissiina,
or by frost.
On the whole, hornbeam woods re(iuire little tending. The
tree stands any amount of pruning. The thinnings are done
on lines similar to those referring to beech durhig the first
THE OAK. 319
half of life ; afterwards hornbeam thins out naturally more
rapidly than beech.
3. Oak — Qiierciis (Tournef.).
The two species of oak which will be dealt with are the
English or pedunculate oak = Quercus jjedunculata, Ehrb., and
the sessile-flowered o&k = Que>-cus sessilijiora, Salisb. From a
sylvicultural point of view they are so much alike that they
may be taken together, any differences being specially noted.
a. Utility.
Oak timber is the most valuable of the indigenous species ;
it is heavy, hard, very durable, and splits well ; it makes
a good fuel. It is used for many purposes, in shipbuilding,
housebuilding, implements, machinery, manufacture of casks
(as split wood), railway sleepers, in fact for any purpose where
a strong durable timber is required. The bark yields an
excellent tanning material. The acorns are good fodder for
pigs and deer, and are also used for tanning and dyeing.
Specific gravity of air dried wood : Pedunculate oak = '76,
sessile-flowered oak ■= '1^.
b. Distribi'fioit.
Pedunculate Oak. — All over Europe up to the 60th degree
of latitude, in North Africa, and eastwards to Syria. It is a
tree of the low lands, but goes up to 1,500 feet elevation in
England, to 3,000 feet in the Alps, and to 4,500 feet in Greece.
It is indigenous in England, Ireland, and in Scotland up to
Sutherland; it ascends to 1,350 feet in the Highlands.
Sessile Oak. — Does not go beyond the 54th degree of
latitude, but rises higher in the hills, up to 4,000 feet in the
Alps, and to more than 6,000 feet on Mount Etna. Somewhat
more a tree of the low hills than the pedunculate oak, but
becomes a tree of the low lands in the northern part of
Europe.
820 NOTES ON ninrisH forest trees.
The pt'dunculate oak is much more fi-equent in Britain
than tlie sessile oak, ])ut the latter is common in Wales.
r. LoidJih/.
Cliiiutfc. — Oak requires warm air; it suffers from late frosts,
l)ut not so much as beech, as it sprouts later in sprin^,' ; it
also suffers from severe winter frosts. It is a light demanding
species, which should have its head free to the full enjoyment
of light. It does not require much moisture in the air. It is
more storm-lirm than any other indigenous species.
The sessile oak requires somewhat less warmth in the air than
the pedunculate species ; hence it goes higher in mountains.
.S'f)/7. — Oak requires a soil which is deep, at least fresh,
warm, and fertile ; it accommodates itself to moist soil, and is
not very sensitive as regards inundations. Fertile loamy soils
cause its highest development, but it is also found on cla , and
on sandy soil if it is sufficiently moist. On the whole it is
one of the most exacting indigenous species. It thrives better
on southern than on northern aspects.
The sessile oak is somewhat less exacting as regards fertility,
and requires a little less moisture in the soil ; hence it is found
in poorer and drier soils than the pedunculate oak. If grown
as coppice, the oak is less exacting than if grown as a tinibei-
tree.
f nirtisi'lhi. The bark is sought
and badly gnawed by the hornet. The Coss'nhf readily attack
it, ZcKzera preferring the saplings to any other food plant.
The bark-beetles, ILih'ainHs fraxini and cnniatiis, kill sickly
trees ; the former also attacks the upper branches of healthy
trees and kills them in a few years.
Cankerous spots in the bark may ])e caused by Xictria
(Utissima.
The thinnings of ash woods should be such as to enable the
tree to lay on diameter increment, in other words to give it a
liberal growing space at all times, and especially with
advancing age,
i). Elm — Ulmus (L.).
The following two species will here be noticed : —
(1.) The common elm= Ulmus campestna, Sm.
(2.) The Scotch, wych or mountain e\vQ.= UhnH>i nioitUina,
Sm.
a. Vlilili/.
Elm yields a coarse timber which is hard, moderately
heavy, difficult to split, very durable, even when exposed
to become alternately wet and dry. Specific gravity of air
dried common elm', mean = '73, of mountain elm = -(il). It
is used for a great variety of purposes in rural districts,
by the carpenter, joiner, wheelwriglit, turner, boat-builder,
and others. It yields a fair firewood, and the leaves are
good foddei-. The ashes yield excellent potash.
h. hislrlbiilion.
Common Kim. — Central and South I'hirope, North Africa
and Siberia ; goes up to 4,000 feet in the Alps. It is found
in England up to an elevation of l,r)00 feet in Derbyshire,
THE ELM. 329
also in Ireland, rarer in Scotland. Introduced into Britain,
where it does not, as a rule, bear fertile seed.
Wych Elm. — Europe and Siberia. Indigenous in Britain,
going north to Sutherland, also in Ireland. Ascends to 1,300
feet in Yorkshire.
r. LomlUij.
Climate. — Elm requires a mild climate, but is not sensitive
to late frost. It is a light demanding tree, but less so than
oak and ash. It is only fairly storm firm, and the branches
of old trees are easily broken.
Soil. — Elm demands a deep, fairl}' porous, moist and fertile
soil to do well ; hence it is mostly found on alluvial soils in
low lands and valleys. The wych elm is somewhat less
exacting than the common elm.
(]. Shnpr anil IkTelopinenf.
The elm divides into branches at about half its height.
The crown of the common elm is narrow and tends upwards ;
the wych elm has a broader crown. The root system consists
of a tap-root with numerous side roots ; at an advanced age
the system becomes somewhat more shallow. It grows quicker
than oak, but rather slower than ash, and reaches an ultimate
height of about 110 feet ; the common elm under specially
favourable conditions up to 125 feet. It attains a consider-
able diameter.* It is a long lived tree, reaching an age of
500 or even more years.
('. Reprodurtive Power.
The elm commences producing seed plentifully at the age of
about 40 years. The crops are heavy and occur about every
2 or 3 years ; in Britain the seed of the common elm very
rarely ripens. On the whole the reproductive power by seed
is great. Both elms have a great reproductive power from
the stool, there being stool shoots and suckers ; they also
* The author has seen, at Schimsheim, in Ehenish Hessia. a cuniiiiou ehii tree
of fourteen feet diameter measured at three feet from the ground.
330 NOTES ON HKITISH FoUKST TKE1-«S.
reproduce well by stem shoots. Trees upwards of 40 years
old when cut over still reproduce well from the stool.
/. ( linruitcr ami Comi>osilion of Woods.
VA\\\ is not well suited for pure woods. It does much better
mixed with beech and hornbeam ; it is also grown with oak,
ash, alder, and others, not unfrequently in coppice with
standards. It holds its own against these species, except
beech, which may outgrow it during the second half of life.
If pure, elm should be underplanted like oak.
//. Si/lririilhirdl Sijsfcms.
High forest, standards in coppice, coppice, and pollards.
//. Fornuilinn of Woods.
The elm is generally planted ; the plants are either raised
from seed, or they consist of suckers or layers. As the seed
of the common elm does not ripen in Britain, it is generally
propagated in the latter way in this country.
The seed ripens in May to June and falls almost immedi-
ately ; it keeps its germinating power only for a short time,
and must be sown at once. If 80 per cent, germinate, it is
considered good seed. There are about 60,000 seeds to the
pound. In nurseries the seed is best sown broadcast and very
slightly covered with fine earth, one-tenth of an inch being
sufficient ; it germinates after 2 — 3 weeks. The seedlings
may be placed in nursery lines in the following spring, and
they are fit to be put out after another year, though they
frequently remain longer in the nursery.
The methods of obtaining layers and suckers have been
shortly indicated on page 221.
i. Tnidinii.
The elm, being hardy and grown mixed with other species,
does not recpiire nnu-li tending. Cattle and deer do damage
by itrowsing, but llie damage is quickly healed. Insects and
THE SWEET CHESTNUT. 331
fungi do a moderate amount of damage. The elm suffers
from two scale-insects, Schizoneura lanigera and Lecaniiun
vagabunchnn ; the latter lives on the stems of saplings, destroy-
ing large patches of bark. Elms have been much injured by
two bark-beetles, Hylcsinns vittatas in Central Europe, and
Scolytus Geoffroyi {destructor, 01.). The latter is exceedingly
harmful to the mihealthy elms growing near large towns ; it
also attacks trees in the open country, selecting weak spots,
generally the extremities of old branches, at the summit of
the tree, and working down the trunk year by year. Of funyi
nothing need be mentioned.
Elm generally holds its own against the species with which
it is usually mixed, except perhaps beech, but from middle age
upwards it must be given a liberal growing space by thinning
aw'ay the other species to a sufficient extent.
6. Sweet Chestnut — Castanea resca (Gsertn.).
a. Uiility.
The chestnut yields a fairly hard, moderately heavy timber,
specific gravity air dried = '61, splits well, durable. Used
for building, in carpentry, staves for wine casks, vine stakes,
hop poles, pit timber, etc. It is not a very good firewood, but;
the charcoal is much appreciated by blacksmiths. The bark
is used for tanning. The fruit is eaten.
h. /Jis/n'buf/o/i.
Asia, Europe, North America. In Europe it is indigenous
in the south and west ; introduced into Britain, where the
fruit rarely ripens fully. It rises to 2,800 feet in the Alps.
In its natural home the chestnut is a tree of the lower hills
and mountains, preferring northern and eastern aspects,
rarely found in the low lands.
r. Locality.
Climate. — Kequires a mild climate, is tender against late
and eai'ly frost and also severe winter cold ; drought also does
•Viz NOTKS ON liHlTISH FoHKST TUKKS.
not suit it. Cliestmit is a light demanding tree, but less so
than oak. During youth it stands some shade, so that it
thrives under Scotch pine woods. Later on in life it becomes
more light demanding. It is storm firm.
Soil. — Chestnut likes a deep, porous, fresh and fertile soil.
It can grow in rather dry soil if deep, but avoids wet localities.
A loam}' sand suits it best ; it does not like heavy soil, and
avoids calcareous soils.
'/. Slmije (till I hi-rcldiuiicnl.
Chestnut has a straight stem, wliicli. Ikjwi-vit, branches at
a moderate height. If space permits, it produces a broad
ci'own, which is fairlj^ dense. The root system is deep going,
resembling that of the oak.
The height growth during youth is somewhat more rapid
than that of oak, but it does not reach the same height as the
latter. It attains a very large diameter.* It is a long lived
tree, reaching an -age of more than 500 years.
r. li)'iii(iduilirr Power.
Chestnut comes into full bearing at the age of about
50 years. Full seed years occur every "2 or 8 years, though
some seed is produced almost annually.
The reproductive power from the stool is very great ; even
the stools of trees up to 100 years old, when cut over, yield
shoots ; the stools last a long time.
f. ('hiiracirr anil Cdiii/ivsHinn nf Wnods.
The chestnut is not very suitable for growing in pure woods
as high forest, as it opens out about the same time as the oak,
though not to the same extent. Such woods require under-
planting, it is, however, grown pure as coppice. It does
well in mixture with beech and oak as high forest ; in coppice
• A cliestniit tree uii Mount Klii:i is reported to have a i:irtli of about
•2m feet (Dohiiur-Xoljbej.
THE SWEET CHESTNUT. 388
it is grown mixed with many species, as beech, oak. ash. ehn
maple, lime, birch, hazel, willow, aspen, etc.
If. Sulririillural Si/steiua.
High forest, standards in coppice, but chiefly coppice. In
Southern Europe it is much grown as a fruit tree in open
woods. As high forest it is treated under a rotation gener-
ally not exceeding 100 years, as coppice under one of 5 to 80
years, according to the size of the required material.
//. Formation of Woods.
Direct sowing is done, but chiefly planting. The chestnuts
ripen in October and fall immediately. They retain their
germinating power for about six months. Of good chestnuts
not less than 60 per cent, should germinate. One pound
contains about 115 chestnuts.
Direct sowings should be made in spring, as the chestnuts
are liable to be eaten by mice if sown in autumn ; they should
not be sown too early, as the young seedlings are tender
against late frosts. The chestnuts should be covered with
about 1^ inches of soil ; they germinate after five or six weeks.
The treatment of chestnut in nurseries is similar to that
described for oak (page 323).
/. Tendiwi.
Young chestnuts must be protected against late and early
frosts, either by sheltering them artificially or by raising
them in sheltered localities. They also require protection
against cattle and deer, which browse them. Further on in
life chestnut suffers much from frost cracks.
Damage by insects and fungi is not of much importance.
The only part of the sweet chestnut liable, as a rule, to damage
by insects is the fruit, the crop of which may be much lessened
by the internal-feeding larvfe of species of Carpocapsida
among the Tortrkcs.
The chestnut stands pruning well.
Thinnings are made as in the case of oak.
.'331 NOTES ON inaTisn torkst treks.
7. Maplk — Acer (h.).
The followiiif,' two species are <];ro\vii as forest trees in
Britain : —
(1.) The great maple, or sycamore = Arrr Paciulo-pJatauua, L.
(2.) The Norway m[iYi\e= Acrr pldtonnidcs, L.
//. niJi/i/.
The white or yellowisli-white timber of tlie two maples is
moderately heavy (sycamore, sp. gravity, air dried = 'r)7,
Norway maple = "74), hard, fairly durable under cover, but of
short duration in the open. It has great heating power, but
is not an agreeable fuel for domestic purposes. It is used by
the joiner, for finer wheelwright's work, carving, mathematical
instruments, rollers in cotton mills, and a variety of other
purposes. The leaves yield good fodder.
The timber of the sycamore is somewhat preferred to that
of the Norway maple.
h. hiHiiilnilioii.
Siicaiiiiirc. — ]\riddle Europe and "Western Asia. Goes higher
in mountains than the beech ; up to 5,000 feet in the Alps.
I'rolxibly introduced into Britain.
Xoriraj/ Maple. — Europe ; goes further north than the
sycamore, up to (52° of latitude ; it does not go in mountains
as high as the sj'camore ; to about 4,000 feet in the Alps. Not
indigenous in Britain.
r. IjintlHi/.
C/n»«7<'.— The maple generally makes small demands on the
temperature, but it suffers a good deal from late frosts, and
also from excessive heat ; it is hardy as regards winter cold.
As regards light requirement, it stands al)Out half-way between
light demanders and shade bearers. Maple is a storm firm
tree. The Norway maple is specially adapted for cultivation
by the seaside ; it is somewhat more a tree of the plains than
the sycamore ; it also suffers somewhat less from late frosts.
.s:o?L— Maple requires a deep, fresh and fertile soil : Norway
THE MAPLE. 335
maple can do with somewhat less fertile soil than sycamore,
also with less moisture, but stands a higher degree of it than
the other maple.
d. Shape and Development.
The stem of the maple, though straight, divides rather low
down into branches ; it forms large oval crowns if grown in
the open, which are of moderate density. In crowded woods
the maple develops a tall, cylindrical stem, with a small
crown restricted to the upper part of the stem. The root
system is deep-going. Maple at first shows quick height
growth, which falls off comparatively early, so that it is liable
to be passed by beech, though it may ultimately reach the same
height. Both maples reach a large diameter, and a great age.
e. Reproductive Poiver.
Sycamore produces full crops of seed after the age of 40
years, Norway maple a few years earlier ; they are not very
heavy, and occur about every other year. On the whole the
reproductive power by seed is good ; that from the stool is
moderate, and the stools do not last long.
/. Character and Composition of Woods.
Though maple is fairly well adapted for pure woods, it is
generally mixed with other species, especially beech, also oak,
and even conifers.
(/. Sylvicuttiirdl Systems.
High forest, standards in coppice, and coppice.
h. Formation of Woods.
Maple is generally planted, though it reproduces naturally
wherever it has a chance.
The seed ripens in September to October ; it falls in
October and into the winter months. The germinating
power disappears rapidly after the following spring. Good
seed should show a germinating percentage of at least 55.
One pound of seed of sycamore contains about 5,000 seeds, of
Norway maple somewhat more.
•■}-5f ]VoO(h.
Pure woods of alder are found in moist or wet localities,
where a sheltering of the ground is either not essential or
even undesirable. It is also found in mixture with other
species, especially with asli, birch, elm, or oak, generally
occupying tlie moister parts of the woods.
//. Sijirinillunil Syslcms.
Alder is mostly treated as coppice, either by itself or as
underwood under standards. It is also found in high forest ;
in that case rarely pure but generally in mixture with other
species. As coppice it is treated under a rotation up to 40
years ; in high forest under one of 50 to 80 years. Coppice
slioots reach about the same height as seedling trees.
//. FarindlUni nf Wuoda.
Alder woods are generally formed by planting, and then
either coppiced, or, if treated as high forest, replanted. The
plants are sometimes raised from cuttings and layers, but
generally from seed.
The seed ripens in October, and falls from November until
spring. It maintains its germinating power for about one
year ; if 80 per cent, germinate, it is considered good seed,
but frequently a much smaller percentage is lit to germinate.
One pound contains about 800,000 seeds.
For direct sowings about 15 })ouiids of seed would be
required i)e)" acre, but su(di sowings are rarely made, ; the
THE COMMON ALDER. 339
seeds should receive a light covering of not more than one-
third of an inch, and they germinate, if sown in spring, after
4 to 6 weeks.
In nurseries a moist part should be chosen for the seed
beds ; at any rate they must be kept moist after sowing. The
seed is sown broadcast. When one year old, the seedlings
may be pricked out, and left one or two years in the nursery
lines.
The planting is mostly done in pits.
/. Tending.
Alder does not require much tending. When quite young
it is liable to suffer from frost lifting, owing to the moist con-
dition of the soil where it is usually grown. This can be
prevented by covering the space between the plants ; any
plants actually lifted must be promptly put back into the
ground.
Considerable danger may threaten alder from the drying
up of the subsoil owing to a change in the level of the ground
water. Such danger must, as far as practicable, be avoided,
by preventing the water from being drained away. At the
same time inundation may do much damage, especially if it
occurs after a wood has been coppiced, and if the water
covers the stools, or if sheets of ice form over young
plantations.
Insects and fungi do little damage. The foliage of alder
may be injured by Tortrix larv?e, or by the plant-beetles,
Agelasticd-aliii and Lina cenea, both uncommon in England.
The bark of young alders is attacked by a weevil, Cryptor-
rJiynduis lapathi, which breeds in their stems. Older trees
are bored by the Cossidce and one or two Sesias.
Of fungi Nectria ditissima may cause cankerous formations,
and Pnhipnrus sulphureus red rot in the stem. Exuascus
borealis causes witch's broom, and several other species of this
genus are found on the leaves and flowers.
z2
;J4II NOTES ON BRITISH FOREST TREES.
9. Birch— 7>'< ////'* aJIxi (L.).
(f. run III.
The timber is fairly lieavv, specilic gravity of air dried
^vood = •()8, moderately hard, does not split well, of small
dural)ility ; good firewood, is also converted into charcoal
for the manufiicture of gunpowder. The timber is used by
joiners, wheelwrights, for coarse ciirvings ; in Britain exten-
sively used for bobbins, also for herring barrels. The branches,
and still more young shoots and trees, are used for withes,
brooms, etc. The bark is used for tanning and the manufac-
ture of small vessels and boxes.
b. I)ishihi(li(in.
It is chiefly found in Northern and Eastern Europe ; also
in Northern Asia and in North America (a variety). In
Europe between 47'^ and 70 latitude. It is indigenous in
Great Britain and Ireland. It is a tree of the low lands, lower
hills, and even mountains. It grows up to 2,500 feet in
Scotland, in the Alps to over 5,000 feet.
r. LoaiUtji.
CliiiKite. — It requires but a low temperature, is frost hardy,
and not particular as regards heat. It is highly light de-
manding, almost as much as larch. It likes moist air. To
some extent thrown by storms. Sutlers somewhat from snow
and rime. It prefers south or west aspects.
Suil. — Birch requires only a shallow soil, with a moderate
amount of moisture ; it is not exacting as regards mineral
comi)osition. Although loamy sand suits it best, it* accommo-
dates itself to all sorts of other soils. It is found on soils
ranging from poor, dry sandy soil to swampy ground, but
avoids stiff clay and calcareous soils.
'/. S//i>/i'- fiinl llcrfliiinHiiil,
The hteiu is generally wavy or undulating, and divided into
branches in the upper part. The trown assumes an elli})tic
THE BIRCH. 341
shape, and is thin. The branches are often drooping. The
root system is weak and shallow.
It grows quickly from the l)eginning, l)ut rarely reaches a
height of 100 feet, generally not l)eyond 70 or 80 feet. Its
volume growth is smaller than that of most other important
forest trees. Its life seldom exceeds 100 years.
p. Rcjiroductivc Poiirr.
Birch begins producing full crops of seed when about 25
years old ; they recur every two or three years and sometimes
annually, and are heavy. On the whole, the reproductive
power by seed is very great. The light seed is easily carried
about, and young birch springs up wherever there is room
for it, owing to the accommodating power of the species.
The reproductive power from the stool is weak ; the shoots
spring chiefly from the root neck ; the stools are Hal)le to die
after two or three rotations.
f. (Jhararler and ('onijjosiiiu/t of Woodn.
Owing to its thin crown and great light requirement birch
is not well suited for pure woods ; nevertheless it appears
pure over extensive tracts in Northern Europe (Eussia,
Scandinavia, and Britain), owing to its great reproductive
power and accommodating character, which enables it to grow
in localities where other species would not thrive, or where
it outstrips them. In such localities its preservation is
justified.
In other localities it should be mixed with species with
dense crowns, such as beech. It is not so well suited for
mixture with conifers, as it injures them Ijy the whip-like
action of its slender branches.
//. Si/h'indlvral Systems.
High forest, also standards in coppice ; little suited for
coppice. Excellent shelter wood over a tender species ;
planted in shelter belts and wind breaks. Useful for filling
342 NOTES ON BRITISH FOREST TREES.
l)laiiks in existing woods. It is treated under a rotation of 10
to ()0 3'ears in high forest, and of 15 to 20 years as coppice ;
for the production of withes it may be cut over after 3 to a
years, according to circumstances.
Ii. Formation of 'Wtmls.
They can be formed artificially or naturally. The seed
ripens from the end of August to October, according to
locality, and commences falling soon afterwards up to
February. It maintains its germinating power for (5 to
12 montiis. It is considered good seed if 20 per cent, of
it germinate. One pound of clean seed contains something
like 800,000 seeds.
Direct sowing is rarely done. Broadcast sowings would
require about 30 pounds of seed per acre, which should be
very thinly covered, only about one-eighth of an inch. The
seed germinates after 2 to 3 weeks. Seed which has ripened
early in the autumn may germinate in the same year : other-
wise it lies dormant till spring.
In nurseries the seed is sown broadcast and covered by
sprinkling a little earth over it. The one year old seedlings
may be pricked out and left for one or two years in the
nursery lines, according to requirements. On the Continent
one or two year old plants are used for planting.
Birch can easily be regenerated naturally under a very
small number of mother trees. Generally it appears wherever
it has a chance of springing up, and the forester has more to
fight against it than to favour it.
/. Tr)iillii;l.
Fcrtilit/i of .S'o/7.— Eaily opening out and a thin crown do
not enable the birch to act beneficially upon the soil ; hence
it should not be grown pure, except on localities where more
valuable trees will not thrive.
KxtcDud Danfji'i-H. — Birch, being very hardy, requires no
tending against climatic infiuences : the damage done by snow,
THE WILLOW. 348
rime, and storms is moderate. It is less nibbled by cattle
and deer than almost any other broad leaved tree. It is
attacked by mistletoe.
Insects. — The leaves support a very large number of larvse,
which, as a rule, are not gregarious. Injury is occasionally
caused by the following species : — Lipar'is dispar, and monacha ;
Eriogaster lanestris, Pi/;i(era hucephala. llhiinchites betuhe
and its allies cut and roll up the leaves. The young stems
are injured or killed by the larvae of species of Agrilas and
Sesia, and by Zeuzera ascidi. The goat-moth, Cossus, lives in
older trees, which are also liable in some localities in X.
Europe to suffer from the burrows of a bark-beetle, Sculi/tas
Ratzehurgi.
Birch has no serious enemies amongst fungi. Exoascus
targidus produces witch's broom ; Poli/punts bctidiuns, red rot ;
P(dijponts hcvigatas, white rot.
Birch is rarely pruned. Thinnings are regulated naturally,
as the weaker individuals are speedily suppressed by a
moderate number of dominant trees per acre. In mixed
woods the more valuable species require, during youth, to be
protected against the birch, as the latter generally grows
quicker.
10. Willow — Scdix (Tournef.).
Of the numerous species of Willow only the following four
need be mentioned here : —
(a.) Common sallow, or goat willow = .S'a/y',i- caprea, L.
(/>,) White willow = Salix olba, L.
{<■.) Crack willow, or withy = Scdix frag ills, L.
(d.) Common osier = Salix viminalis, L.
The willows yield a soft light timber which is little prized,
except for some special purposes, as for cricket bats ; their
principal value consists in yielding withes and materials for
basket work, cask hoops, etc. The wood is not good fuel, but
may l)e converted into charcoal for the manufacture of gun-
powder. The bark is used for tanning. The osier yields the
•*{ll NOTES ON BTITTISH FOHKST THKKS.
liirgest quantity of material for basket work, Imt xarioiis other
species are grown for the same purpose.
'/. Common Sallow.
The sallow occurs all over Europe, North and West Asia,
Himalayas, It is found in Great Britain up to Inverness, and
in Ireland. It ascends to 2,000 feet in the Highlands and to
about 5,000 feet in the Alps.
It is a tree of the low lands and outer hills, prefers a fresh
soil, but can do even with dry soil ; appears on calcareous
soils. The tree is little exacting in respect of climate and
hardy. It is light demanding, of quick growth, and has
a thin crown which cannot do justice to the soil.
It is treated as coppice wood, under a rotation of 10 to 15
years, having a good reproductive power from the stool; yields
firewood, withes and fascine wood. It appears plentifully in
high forest, but is generally removed in the cleanings and
early thinnings.
The seed of this willow ripens in May or June, and must be
sown at once, as it does not preserve its germinating power.
Sowings of willow are, however, never made in sylviculture.
The tree is propagated b}' cuttings. These are cut, from a foot
in length and upwards, from the previous year's wood, though
older wood may also be used. The cuttings may be placed into
a nursery for one year, or planted out at once. Unless the soil
is very loose, holes should be made, into which the cuttings are
planted. The area should be kept clear of weeds, and the
surface soil loosened between the cuttings.
It is nibbled by cattle and deer, and peeled by mice.
h. Whilr Willoir.
Europe, North Africa, North and AVest Asia, North-West
India. It is planted in all parts of Great Britain and Ireland,
generally along the banks of rivers. It likes fresh, loose soil,
especially of a loamy nature, but is not very exacting ; is light
demanding, grows rai)idly, has a thin crown, and is hardy.
THE WILLOW. '6i.b
The white willow is hest adapted for pollarding (topping),
less suited for coppice. It also appears in high forest amongst
other species. As pollards, it is worked under a rotation of
three to six years ; the material is used for fascines, cask
hoops and basket work.
It is propagated by cuttings, which may be five and six
feet long, so as to produce a tree in the shortest possible
time.
As regards animals, see common sallow.
r. ('rark Willoir.
Europe, North and West Asia. Planted along river banks
and low land generally ; likes moist or wet soil, especiall^^
loamy sands ; light demanding, thin foliage ; grows rapidly ;
hardy, but suffers from snow and rime ; good power of
reproduction by shoots.
It is suited for pollarding and coppice, and is treated like
the white willow ; the shoots are not suited for basket work,
as they are liable to crack.
(I. Common Osier.
Eussia, North Asia ; cultivated throughout Europe. It is
extensively grown in osier beds, which are generally established
along river banks and other low lying parts of the country, on
loose, moist, sandy soil ; it is, however, exacting as regards
general fertility of the soil. It is light demanding, with a
thin crown ; grows rapidly ; fairly hardy, but suffers sometimes
from frost, insects and fungi.
The osier is treated as coppice. The rotation depends on
the desired material, and ranges from one to six and even
eight years. Material for fine basket work is obtained by
cutting annually. Reproduction is powerful, but the stools do
not last for more than perhaps 15 years, and fre(|uentl3' not so
long.
The osier is propagated by cuttings as described for the
common sallow. In England the cuttings consist frequently
846 NOTES OX BRITISH FOREST TREES.
of whole shoots, of which only about one foot of the lower end
is inserted into the s^'onnd ; the}' are planted immediately
iiflei- (•uttin<^'.
Ill Sir Is 1)1/11 n'ai/fi lu Williiirs i/niny/lh/.
Willows generally are injured l)y numerous insects, which
are common to most species. The wood, chiefly of Salir allxt,
is much attacked by Aromia moschata, Lamia tc.rtor, and other
Longicorn beetles, and by the ,c;oat-moth, Cossiis. The leaves
are attacked by various liombi/ces, as lAparis saliris and
Piliict'])liaht ; by sawfly larv?e, and by plant-beetles,
esi)ecially the species of PIn-afora and Galcnica. These are
very injurious to Salix riiitiii(ili>!, as are the leaf binding larvae
of Earias rliJomna. The twigs are injured by Sesi'uhc and by
gall-gnats (Cccidoiin/'uhf). A weevil, Cri/ptorrJii/iicJiiis lapatJii,
destroys the bark and shoots, especially of S. riiuinalis.
Of finifii, several species of Melampaora produce a rust
which causes the leaves to die. Poli/ponis xiilpJnircns \n-o-
duces red rot in the wood.
11. Vovh\R—P()})i(h(^ (Tournef.).
The following three species must be mentioned : —
(«.) Aspen = PopiiJiis tremida, L.
{!).) White poplar, or abele = Popnlits alha, h.
(c.) Black poplar = Popidiis )ii;ira, L.
f/. Aspeji.
i. Utimty.
The aspen yields a soft light timber, of small durability in
the open ; average specific gravity = '51 ; heating power small.
It is used sometimes under cover for buildings, for packing
and cigar cases, rough cooperage, inner work of carriages,
manufacture of matches, and of paper. The charcoal is used
in the manufacture of gunpowder. The bark is used in
taiining and dyeing (for the latter purpose also the leaves).
THE POPLAR. 847
ii. DrsTKiBrnoN.
Europe, North Africa, North Asia. Indigenous in Great
Britain and Ireland. Ascends to 1,600 feet in Yorkshire ; to
4,000 feet in the Tyrol. Found over extensive areas in North-
East Europe.
iii. LdCALiTV.
Climate. — Hardy against frost and drought. Highly light
demanding, likes moist air, subject to be thrown by storms.
Soil. — Grows almost anywhere, except on very poor dry
sand ; moist loamy sand, rich in humus, suits it best. It is
generally very accommodating.
iv. Shape and Devkloi'Mknt.
It develops a tall stem with a thin crown, reaching a
maximum height of about 110 feet. It is of quick growth and
short lived, rarely reaching an age of more than 100 j-ears.
V. ReI'KODUCTIVE Poweu.
Great by seed ; sends out numerous root suckers.
vi. C'HAllACTEK ANU COMPOSITION OF WoODS, SyLVICULTUIIAL SYSTEMS.
Earely pure. Usually appears in high forest in mixture
with other species, also occasionally as standards in coppice.
Generally cut out in thinnings, as it becomes ripe in about 50
to 60 years, or threatens to injure the more valuable species.
vii. Formation of Woods, Dangeks, Tending.
Aspen is generally propagated by root suckers, sometimes
by layers ; cuttings strike less well. It springs up readily
from seed in open spaces, and in young woods of other species.
The young trees are nibbled by deer, also peeled. Subject to
much injury by insects. Eequires no special tending.
Ik White Poplar.
Europe, North Africa, North and West Asia, N. W.
Himalayas. Indigenous in Great Britain and Ireland.
'3J-S NOTES ON lililTISH I'OKKST THKKS.
Timber li^'ht. soft, spei-itic .t^ravity = -45 ; used for similar
purposes as tliat of aspen, hut more valued.
Found in low lands and river vallej's, likes deei), loose,
moist soil, more exacting than aspen. Growtli quick, some-
times reaching a height of 100 feet and a diameter of 1 foot
in 40 — 50 years ; stem straight ; is light demanding ; foliage
somewhat denser than that of aspen. Eeproductive power
good, especially root suckers.
Best propagated by root suckers, less well by cuttings.
Treated as pollards, less suited for coppice. Occasionally
standards in coppice.
r. Hhirk Poplar.
Europe, North Asia ; not indigenous in Britain, but planted.
Timl)er light, soft ; specific gravity = "45 ; most valued next
to tlial of wliite poplar, and used for similar pur^joses.
Appears in low lands and river valleys. Thrives on any
soil, if loose and moist ; does not like heav}^ soils. Grows
rapidly, developing a straight stem, light demanding, hardy.
Eeproductive power good by stool shoots and root suckers.
Best propagated by cuttings of various length. Treated as
pollards, sometimes standards in coppice.
IiiticctH iiijiiriotis to poplars (lowralhj : —
The leaves of young poplars of all species are much
devoured by larvic, which are not gregarious, except those of
Dicraiiiira and Lij)((ris .s7///r/.s-. The plant-beetles, Linn jkijuiH
and trciinihc (an aspen feeder), also attack them. A Longicorn
beetle, Saperda popnlneci, breeds in the twigs of young aspens,
causing gall-like swellings and crippling the growth of the
plant. Its congener, Sapcrda (■(irrluirhia. breeds in the stems,
chiefly of black poplar, from f) to 20 years old, and is a great
hindrance in many places to growing the tree. \'arious clear-
wing moths, especiall,y Sesla apij'ormiii, and the goat-moth,
Cossii.s, feed in the wood, often in company with Sapcrda.
Oi/iniiii, Mrlainpsora species produce a rust on the leaves.
The mistletoe is fre(jueiitly f(jund on poplars.
THE LIME-TREE. 84-9
12. Lime-Tree or Linden — Tilia (L.).
Two species of lime-tree have to be mentioned : —
(1.) Small leaved lime-tree = Tilui parrifolia, Ehrh.
(2.) Broad leaved lime-tree = 7't//a r/raiulifolin, Ehrh.
The former is the more important forest tree. An inter-
mediate species is Tilia intcnnedia, D.C.,or Tilia europcea, L.,
in Britain called the common lime-tree.
a. Utility.
The wood of the lime-tree is very light and soft, little
durable, and of small heating power. Specific gravity about
•45.
The timber is not fit for building purposes, but is used for
tool handles, by joiners and coach-builders, for carving, piano
sounding boards, cigar boxes, and for paper manufacture ;
young shoots are used for withes. The charcoal is used as
crayons and for the manufacture of gunpowder. The bark
yields bast for ropes, mats, packing, etc. The flowers yield a
medicinal tea.
The timber of the small leaved species is somewhat denser
than that of the broad leaved lime-tree.
Ii. iJisfrilnitii)//.
The small leaved species occurs in Europe from the 62"^ of
latitude southwards. North and West Asia ; goes up to 3,300
feet in the Tyrol. The broad leaved species is indigenous in
Middle Europe and West Asia; goes up to 2,800 feet in
the Tyrol.
Neither species is indigenous in Britain.
r. Locatitij.
Climate.— The lime-tree is frost tender, and still more
sensitive against drought. It is by some considered a light
demander, by others a shade bearer ; practically it occupies a
middle position in this respect. It is fairly storm firm.
35U NOTES ON BUITISH FOREST TREES.
Sail. — A deep, thoroughly fresh if not moist, fertile soil.
The small leaved lime-tree is somewhat less exacting as
regards hoth climate and soil.
//. S/t(t/ii' 1 1 IK I hrrcloiniiint.
When grown in the open, the lime-tree forms a fairlv tall
tree with side branches coming low down the stem. In
crowded woods it develops a tall cylindrical stem, with the
crown reduced to its upper part. The root system is deep
going. It is of quick height growth during youth, subse-
quently similar to beech, reachmg about the same height. It
attains a large diameter and a very great age.
c. Ii('iiru(luilii'i' I'dirir.
The lime-tree commences producing full crops of seed after
the age of 30 years, and they occur about every other year,
showing a fair reproduction by seed. Reproduction from the
stool is excellent, and the stools last a long time.
f. ('Ii(iii(rlcr ami Cuinpiislllun nf Wands.
The lime-tree is, owing to its dense foliage, well suited for
pure woods, but, as the timber is of inferior (juality, it is not
so grown, except in some parts of Xorth-Eastern Europe (the
small leaved species). As a rule it is found mixed with other
broad leaved trees.
J. SijIrkuUuial Suslvnis.
High forest, and coppice either simple or under standards
of other species. It makes a good soil protection wood, and is
also pollarded.
//. F(iniiii(iroLlvclive Power.
It bears full crops almost every yeai-, commencing at an age
of about 10 years. The reproductive power from the stool is
good, and the latter last long. The shoots start mostly below
the surface.
f. Character of Woods.
It has a beneficial effect upon the soil.
//. Sjilriridlural jSi/sle/iis.
It is generally grown as coppice, as underwood under
standards, soil protection wood under oak, also suitable for
hedges.
//. Fonnalidii of Woods.
From seed, or by layers.
The fruits ripen in September, and fall from October
onwards ; they retain their germinating power for about six
months. The nuts must be well covered with earth and
protected against mice.
/. Ti'ihliHil.
The young plants must Ix; protected against cattle, deer
and rabbits.
THE SILVER FIR. 353
Hazel is not often seriously injured by insects. The cater-
pillars of some BoDtljyccs and Geometrce thin the leaves
occasionally. The species of Balaninus at times greatly reduce
the crop of nuts.
The branches show cankerous places, which may be due to
Nectria ditissima.
14. Silver Fm = Abies ijectinata (D.C.).
a. Ufilify.
The timber is light, specific gravity of air dried wood on an
average = "48 ; soft, easily worked and splits well ; lasts well
in dry localities, less so if exposed to w^eather. Timber of
quickly grown trees is less durable than that of slowly grown
trees such as are produced in crowded woods. It is used in
Britain for a variety of purposes, principally as boards, planks,
rafters, and small boxes for packing strawberries. Used for
the manufacture of paper. Strasburg turpentine is obtained
from this tree.
//. Disfrihufioii.
It is found naturally in temperate Europe between the 36°
and 52° of latitude. It is not indigenous in Britain ; said to
have been introduced about 300 years ago (1603 according to
Brown). In its natural home it is a tree of the lower
mountains, ascending to 2,500 feet in Central Germany, over
4,000 feet in the Alps, and 6,000 feet in the Pyrenees.
r. Locality.
Climate. — Silver lir requires a fairly warm climate, and
stands in this respect near the beech. It is subject to injury
by late and early frosts, and is also tender as regards drought.
It stands a great amount of shade, even more than beech ; in
fact, more than any other forest tree mentioned in this part.
It requires a certain amount of moisture in the air, but not so
much as spruce. Northern and eastern aspects suit it best.
It is fairlv storm firm.
.•i54- NOTES ON BRITISH FOREST TREES.
,S',>//. — Silver lir requires a deep, fresh and fertile soil,
rather binding than loose. Loamy soils suit it best, though
it will do well on sandy soils, if fresh. Dry or acid soils do
not suit it.
il. Slnijir (Hill l)i'Vrloinm-iil.
The silver lir develops a slrai«^ht and undivided stem,
occasional forking excepted, with comparatively thin branches.
The crown maintains a conical shape until the height growth
has been completed, when the top becomes Hat ; in free
standing trees it extends almost down to the ground, and even
in crowded woods to nearly one-half the length of the stem.
It has a fairly deep going root system.
Silver tir is of very slow height growtli during the lirst 10 to
15 years of life, then the rate increases to such an extent that
it reaches ultimately a greater height than any other British
forest tree except spruce and the recently introduced Douglas
tir. Woods of an average height of 120 feet are frequently
seen, and single trees occasionally attain a height of 150 feet.
In volume increment silver tir is probably only surpassed
by the Douglas tir. Silver fir rarely reaches an age of more
than 800 years.
r. Rt'iiiiKhirlirr Poircr.
Silver iir produces full crops of seed from the 70th year
onwards. Such crops are but light, and in favourable
localities they occur at intervals of two to three years. On
the whole the i-eproductive power by seed is not great. Repro-
duction from the stool may be said to be nW.
/'. (lidraricr (did Coiiiiiusilioii nf Woods.
Silver lir is excellently suited for pure woods; it has a
dense foliage, and maintains a cover overhead to an advanced
age, under ^Yhich a thick growth of moss springs up, thus
preserving a suitable degree of nu)istur(; in the soil.
It also forms a suitable stock with which other valuable
timber trees, such as spruce, larch, Scotch pine, oak, etc.,
may be mixed. It is most frequently found mixed with spruce.
THE SILVEK FIR. 355
as it has the same shape and approxnnately the same height
growth. Silver fir, being deeper rooted, protects the spruce
from being thrown by storms. Another most excellent
mixture is silver fir and beech, as they make similar
demands on the locality. Oak in mixture with silver fir
does well, provided the former has a decided start to prevent
being outgrown. Silver fir is a very useful species for under-
planting oak, larch, and Scotch pine, when these species
commence to thin out, while they afford to the young silver
fir the necessary shelter against late and early frosts and
drought.
//. Sijlvicultnral Systems.
Silver fir is only adapted for high forest, more particularly
for the shelter-wood systems with natural regeneration by
seed. If grown on blanks it requires nurses to protect it
against frost and drought while young. It may be seen
occasionally as standards in coppice, but this is not advisable,
owing to its dense foliage. As it does not reproduce from the
stool, it cannot be grown as coppice ; it makes, however, good
hedges.
Silver fir is generally worked under a rotation of 100 to
140 years.
//. Fonniitioii of Woodx.
Silver fir is, even more than beech, adapted for natural
regeneration under a shelter- wood. Direct sowing and
planting should be done under a shelter- wood ; if this is
not available it must be supplied artificially, otherwise the
young trees will suffer from late and early frost, and possibly
also from drougbt and insects.
The seed ripens in September to October, in England
towards the end of the latter month. As the seed falls at
once, the axis of the cone alone remaining on the tree, the
cones should be gathered as soon as ripe. Tbe seed rarely
keeps its germinating power for more than six or seven
months. If 40 per cent, germinate it is considered good seed.
A A 2
356 NOTES ON BRITISH FOREST TREES.
One pound of seed contains about 10.000 clean ^^ni'mi^ with-
out wings.
Direct sowings may l)e made in si)ring or autmnn. tlie latter
season being on the whole preferable, as the seed is diilicult
to keep. If spring sowings are decided on, the seed must be
kept in an airy loft and occasionally turned. Spring sowings
sprout after three to five weeks. About -10 pounds of seed per
acre are required for l)roadcast sowings ; it receives a cover of
about two-thirds of an inch. Sowings in patches under the
shelter of existing woods are more frequent than broadcast
sowings.
In nurseries the seed may be sown in drills, or broadcast :
the seedlings should remain for two years in the seed l)ed, and
two years and upwards in nursery linos. In Kngland they
are rarely put out under live years old; the })lants may be
placed :-3 to 4 feet apart. The young plants generally retjuire
protection against frost and drought.
The silver iir is best regenerated naturally under a shelter-
wood, the selection and group system being perhaps even
better suited to it than the compartment system. The process
of regeneration is a slow one. In most mature silver fir woods
groups of advance growth are found, where operations may be
commenced. By removing the shelter trees standing over
such advance growth, and gradually the adjoining trees,
regeneration extends all round, and the groups expand until
they ultimately merge into each other. In this way the
regeneration period of a wood may extend over 30, 40, and
even 50 years. The old trees, being gradually placed into an
open position, increase rapidly in diameter, volume and value.
At the same time they should be removed when the young
crop demands it.
/. Tc/u/in;/.
FcriHitij oj Soil. — Silver lir, if treated i)roperly, is an
excellent preserver of the fertility of the soil.
Kxtcnial J)(ui'j(rn. — The young trees requije shelter against
THE SILVER FIR. 357
frost and drought for 10 and sometimes even 20 ^-ears. This
is given either by the mother trees or by an artificial shelter-
wood of larch, Scotch pine or birch. This period passed, the
tree is comparatively free from danger. Storm and snow may
do damage, but not nearly so much as in the case of spruce.
Cattle and deer nibble it, and the latter sometimes peel it, but
it heals such damage easier than the other conifers. Squirrels
bite off the leading shoots.
Insects are, on the whole, not very destructive. Two species
of Tortrix (T. iiinnuaiui and riifiniifrana) destroy the needles
and shoots, especially in Central Europe. A weevil, Pissodes
})ice(e, peculiar to this species, is destructive chiefl}^ to sickly
trees. The wood-wasps {Sirci^ and some T<»mcld(f' bore into
the wood, especially when newly felled. A scale insect is
likely to attack young silver fir, whenever it is grown without
shelter.
Mistletoe is frequently found on silver fir, perforating the
wood and reducing its value.
Of Fumji, J'^cidiiim datintim, Lk., must be mentioned,
which causes witches' broom and canker on the silver fir ;
this evil occurs sometimes on a large scale. To meet it the
diseased stems should be cut out as soon as possible. Of
other fungi, Pliytophthora omnivora, Pestalozzia Hartif/ii,
Agariciis mdh'tts and Tminetes radiciperda may be mentioned,
but they do less damage than in the case of spruce.
The silver fir stands j)r»»/??_r/ well.
If silver fir is mixed with other species, it should be care-
fully watched, as it is liable to be outgrown and injured owing
to its slow growth during early youth.
Thinnings rarely need commence before the 25th or 80th
year ; they should be light until the woods enter the last third
of their life, when they should be heavy, so as to cause the
remaining trees to increase rapidly in diameter. Throughout
the thinnings, and especially the early ones, all trees infected
with canker should be removed, even if by so doing the leaf
canopy should be temporarily interrupted ; in many cases it
•"55 S NOTES ox r.lUTTSII FOREST TREES.
in;iy hv possil)l(' to romovc (lie witches' l)rooin Ijefnrc llie stem
lias l)ecoinp infected.
15. Common ok Norway Spruck = Picca cxcclm (Link.).
o. llillln.
Tlie timber of the spruce is light, with an average specific
gravity of '45 ; soft and splits well : somewhat more durable
than that of silver fir. It is known in fjritain as white ]^)altic
pine, the principal tree of the European timber trade, and
used for a great variety of purposes, chiefly in the shape of
boards, planks, and scantlings. The timber grown in Britain
is frequently of inferior quality, owing to its rapid growth in
insufficiently stocked woods. It yields a fair fuel, and is used
for the manufacture of paper. The bark is used for tanning.
The tree yields turpentine.
//. l)isiribi M.nu' ivas.,11 |,, believe thai t liis is i.leiil ieal willi Chrrnirs Inriri^!.
tlio insect l)rct'rt»//('/-.s. — Scotch pine requires no protection
against frost or drought ; frost lifting may occur in early
youth. It suffers, however, very much from snow and rime,
and Scotch pine woods are much exposed to fires ; to protect
them against the latter regular fire traces must be cleared,
and a strict watch kept during dry weather over the use of
fire in the woods and in their vicinity. The tree is not much
sul)ject to be thrown by wind, except on a shallow soil over an
impermeable stratum ; its branches and top are, however,
liable to be broken.
Scotch pine is nibbled by cattle and game, but rarely
peeled. Eabbits do much damage by peeling the bark of
young trees near the ground, and squirrels by peeling them
later on in the upper part. The number of these animals
should be reduced by shooting, or trapping in the case of
rabbits.
Scotch pine is liable to a greater variety of insect injuries
than any other tree, especially when grown on poor soil.
Seedlings are destroyed by wire-worms, Tipula larvae, and
milhpedes, also by chafer-grubs. Young plants (2 to o years)
are injured by root-feeding bark-beetles {Hijhistrs), and they
are gnawed by numerous weevils, especially Hijlohius ahietis,
which kills a large number. The needles are destroyed by
the larvae of LijMiris nionaelia, Fidoiua, Trachea, and other
moths, Lnplii/i lis pint and other sawflies ; and on the
Continent by Gastropaelia pini, which frequently kills the
trees, lletinia larvae cripple the terminal shoots, which are
also thinned out by Hylurgus pinipevda. Many weevils,
Pissodes, Magdalinus, Tomicus hidentatus, etc., live in the bark
;it)S NOTKS ON liJMTISII 1-CtKKST THKKS.
and twigs. Tlie Siriciihr and Lon^Mcorn beetles live in and
destroy tlie wood.
Fnmji prey upon ScDtcli pine to a very considerable extent.
Phi/lopliihoia o/iinironi kills very young seedlings. Young
plants and trees up to an age of about 30 years lose tlieir
needles after becoming yellow or brown ; the cause of this has
not yet been satisfactorily explained, though in many cases a
fungus (Ili/stcriiini I'iiiastri) is present, and may occasion the
disease, which is termed Schiitte in German. Both Anaricioi
iiiellciis and Trametes laduipcrda do much damage. Peridcr-
iniuiii pini causes canker by drying up the bark and cambium
all round tbe tree, and kills the part above it ; such trees
are called "' foxy " in England. ^Vilite rot is produced by
'PraiiiitcH pini ; red rot b}' Poliijtonia iap(>r(tiiii>; and mollis ; a
bluish-black rot b}' Ceraatoma pilijrnim.
Pni)ii)ifi of green branches cannot be recommended; dry
branches may be removed. Occlusion is slow.
ThinniiKjH may be commenced between the ages of 15 to "20
years, according to circumstances ; they should be light and
irequently repeated until middle age. If it is then decided to
underplant the Scotch pine, the thinnings must become
heavier ; if not, they should continue to be moderate, so as to
preserve as complete a cover as practicable. At the same
time, trees are constantly dying off from various causes, such
as insects and fungi, or they are broken by snow and rime.
Such trees must be removed as speedily as possible ; hence
dry wood cuttings are more frequent in Scotch pine woods
tlian in anv other.
17. Jjlack oil AusTiUAN I'lNK ^ Pitnis Luiuio (Poir.), var.
anstriara.
ii. nmiij.
The Austrian pine yields a light soft wood, which is very
rich in turpentine, and very durable. Specilic gravity, air
diicd, = "5H. It is a good building timbei', and in its natural
THE AUSTRIAN PINE. 369
home the tree yields more turpentine than any other European
conifer. The needles are used in the manufacture of an
article which comes into commerce as " forest wool."
//. Disfrihvtinn.
Lower Austria, Hungary, Croatia, Dalmatia and the south-
eastern Alps, where it ascends to about 4,500 feet. Introduced
into Britain during the last century.
c. Loi'iilitfi.
Climate. — The tree is frost hardy and not sensitive to
drought. It demands light, but stands more shade than the
Scotch pine, standing between that tree and the Weymouth
pine. It prefers dry air, and is storm firm. Suffers much
from snow and rime, even more than Scotch pine.
Soil. — It likes a moderately deep, porous and fairly moist
soil, which need not be fertile. In its natural home it is
chiefly found on calcareous soils, especially over dolomite
formations, but it thrives almost equally well on any other
formation. Its demands on fertility and moisture are even
less than those of the Scotch pine, so that it grows on shallow,
dry soils, even on rocks. It is considered one of the least
exacting of the European timber trees.
(/. Simpe and Development.
The tree develops a straight stem ; the crown is similar to
that of the Scotch pine, but fuller, stronger and denser. Its
height growth is somewhat slower than that of the Scotch
pine, and it does not, as a rule, exceed a height of 75 feet, at
any rate when grown beyond its natural home. The root
system is strong, and similar to that of Scotch pine. The
volume growth is smaller than that of Scotch pine. It is said
to attain a great age in its natural home.
e. Reprodiutive Power.
The tree commences producing full crops of seed after it has
passed an age of 30 years, and they occur every 2 to 3 years,
s. B B
370 NOTES ON BRITISH FOREST TREES.
f. Cliurorli'r and Co/iijiosilion of Wooi/s.
The Austrian pine appears in extensive pure woods in its
natural home, and it is better suited to be so grown than the
Scotch pine, because it has a denser crown, whicli sliades the
soil better, preserves a complete leaf canopy to a more
advanced age, and acts beneficially on the fertility of the
locality. It can be mixed with the same species as Scotch
pine, but demands more protection against being outgrown
and suppressed. It does not require underplanting to the
same extent as Scotch pine.
I/. StjJvknJtural Systems.
High forest with clear cutting, but also the shelter-wood
systems. It can be used as nurses over and between lender
species ; makes a good wind break along the edges of woods.
h. Formation of Woods.
Planting is the rule, but sowing and natural regeneration
under a shelter- wood, or by adjoining woods, are also practised.
The seed ripens at the end of October in the second year,
and falls towards and during the following spring. It retains
its germinating power for 2 to 3 years. Of good seed 70
per cent, should be capable of germinating. About 24,000
clean seeds go to the pound.
The treatment of the seed and seedlings in the nursery is
the same as for the Scotch pine.
/. Tend'nKj.
This is similar to that of the Scotch pine. The Austrian
pine is exposed to the same dangers as the Scotch pine, but in
a less degree ; from snow and rime it suffers, however, some-
what more. It has the same insect enemies as Scotch pine,
but is less frequently injured. A snail {BuUmus delictus) is an
especial foe to young plants, which it kills by eating the last
year's needles in spring.
THE CORSICAN PINE. 371
Fungi are the same as tliose found on the Scotch pine, but
they do less damage.
18. CoRsicAN Pine — Piiins Laririo, var. Corsicaiia (Poir).
rf. Tlilihi.
Similar to that of the Austrian pine.
b. Dislribution.
Corsica, Sicily, Calabria, Spain, Greece, South Piussia,
generally the south of Europe. Introduced into England
about the year 1815. In its natural home the Corsican pine
is a tree of the mountains.
c. Lor/, and
THE LAECH. 375
older ones by the gnawing and breeding of a weevil, Pissodes
pini, as well as by a woolly aphis Cryptococcus, sp. A bark
beetle, Tomicus hideiitatus, is occasionally injurious.
The Weymouth pine suffers from many of the fungi which
attack Scotch pine, but in a less degree. Agar'uus melleus and
Trametes radiciperda, however, do more damage, as they
frequently kill young trees of this species.
The woods should be kept crowded so as to kill off the lower
branches, hence thinnings must be light until the height
growth falls off. The dry branches remain for a long time on
the stem, and it is desirable to remove them. Cutting oft"
green l)ranches cannot be recommended, because it causes the
stems to grow unevenly.
20. Larch — Larix europcea (D.C.).
a. Utilify.
The timber is moderately heavy, average specific gravity,
air dried, = '62, soft, splits fairly well, very durable, lasting
longer than any other coniferous timber grown in Britain ; it
yields good firewood.
Larch is the best coniferous timber grown in Britaui, for
construction above and below ground ; it is also used for ship
building. Li Britain it is used for a great variety of purposes ;
it is much prized for railway sleepers, mining purposes, and
makes ah excellent fencewood. Its price per cubic foot is
generally about double that of Scotch pine timber. The bark
is used for tanning and dyeing. It yields Venetian turpentine.
h. Distrihufion.
The homes of the larch are the Alps, the Carpathian and
Moravian mountains, and Siberia, the latter being now
considered a separate species. It has been cultivated in many
countries, so that it is now found all over Europe between
about the 42nd and 58th degrees of latitude. Larch is a true
mountain tree ; it is generally found in the Alps between
;i7t) NOTES ox BRITISH FOKP]ST TREES.
3,000 and 0,000 feet elevation, l)ut goes up to 7,000, tliat is to
say to the upper limit of tree growth. It is said to have l)een
introduced into Britain in 1629 (Brown). Its cultivation in
Scotland was commenced about the year 17'25.. the Duke of
Athol having begun planting it over extensive areas about
that time. It is found in the Highlands up to about 2,000 feet
elevation, though its cultivation above 1,500 feet frequently
does not pay under present conditions.
r. LonilUy.
Climate. — Larch can do with a lower mean annual tempera-
ture than any other timber tree mentioned in this part. It
suffers from drought, is hardy against frost in its natural
home, but liable to suffer somewhat from late frosts in low
lands owing to its very early sprouting in spring. It is
highly light demanding, and requires to liave its head free
throughout life. The climatic conditions required by larch
have been much discussed. The majority of foresters believe
that it prefers a dry atmosphere, a free and airy position, and
northern and eastern aspects. It is more storm firm than
almost any other conifer.
Soil. — Larch requires a deep, fairly porous, and moderately
fresh soil ; it avoids wet as well as drj' soil. It is fairly
exacting as regards the general fertility of the soil ; loamy
soil containing a good proportion of potash and lime suits it
best ; in its natural home it is much found on stony soils,
provided they are fresh.
The natural home of the larch enjoys only a short growing
season, with a late and very short spring and comparatively
hot clear summer. These are conditions which seem to suit
it. Britain, on the other hand, shows a much longer growing
season, especially a long spring, a moister atmosphere and a
more cloudy summer — in other words conditions which are
altogether different from those prevailing in the natural home
of llie larch. It is not nstonishing, therefore, that this vahiublc
THE LARCH. o77
tree, although it grows most vigorously, suiters excessively
from disease in Britain, as will be indicated under /.
'/. SJiape and Dcrclnimu'iil.
Larch has an undivided stem, with a conical thin crown ;
where the tree is exposed to wind the lower part of the stem
is frequently curved. In crowded woods the branches aie
restricted to the uppermost part of the stem. It develops a
tap root and generally a fairly deep going root system.
It is a quick height grower from the beginning and until it
has reached nearly its full height, w^hich may under favourable
circumstances be placed at about 120 feet. As regards volume
increment it stands between the firs and the pines.
Ordinarily it would not exceed an age of 300 years, though
it is said in the Alps sometimes to reach double that age.
<-. ReiiniiliirUi'fi Poircr.
Full seed j^ears connuence at the age of about 3U years ;
they are light, and may be expected every 8 to 5 j^ears. A
certain quantity of seed is produced almost every .year. On
the whole, the reproductive power by seed is moderate.
Larch possesses a certain power of reproduction by shoots,
but this is of no practical value in sylviculture.
/'. (Jharacter ami Cinniinsiliun of Wnuds.
Larch preserves a sufticient cover overhead only for a limited
period, generally not exceeding 30 years, when it begins to
thin out admitting sun and air currents, which cause the
fallen needles to decompose quickly, and the previous growth
of moss to make way for grass. Hence, it is not suited for
pure woods except on fertile soils or under specially favour-
able climatic conditions. It is far preferable to mix larch into
other species with a dense foliage, such as beech, silver fir and
spruce,* against which it holds its own. Id Britain it is also
* If Euvthtr investigation should show that Chermes laricis and ahietis are
the same insect, a mixture of siiruce and larch may ])ecome uiidesira])lc.
378 NOTES ON UKITISH FOREST TREES.
mixed with oak, chestnut and Scotch pme, but these niixtuies
are not good ones in themselves ; if they are nevertheless
employed, the reason is to be found in the fact that these
three species are more valuable as timber trees than the
above mentioned shade bearing species, and because in the
moist climate of Britain a departure from the rules, which
guide the forester in arranging mixtures, is more permissible
tlian in dry Continental countries.
Whenever larch is grown pure, it should be underplanted
at the age of 15 to 30 years with one of the shade bearing
species mentioned above. In addition, the Douglas fir may
be suggested for this purpose, because it stands sufficient shade
to grow under a thin larch wood, it requires some protection
during early youth, is a fast grower, and yields valuable
timber. Even the Weymouth pine may do for underplanting
the larch, provided the latter is strongly thinned beforehand.
//. Sijlvimltvre Sijstcms.
Larch is treated as high forest, as standards over coppice,
and it is frequently grown as a shelter- wood over and between
tender species. In high forest it may be treated under a
rotation of GO years and upwards, according to the size of
timber required. It is useful to fill blanks in existing woods,
owing to its rapid growth.
//. Formnlion of WooiU.
Larch may be planted on clear cuttings ; rarely sown ; in
favourable localities it can also be naturally regenerated. Care
in selectioji of sites is essential, to })revent disease being brought
about by unfavourable soil and climate.
The seed ripens in October or November, and begins to fall
in the following spring ; some of it remains in the cones until
the spring of the second year, or even longer. The empty
cones renuiin for several yeais on the trees. The germinating
power is maintained from 2 to 1 years. If 85 per cent.
THE LARCH. 379
germinate it is considered good seed. One pound of seed
contains about 70,000 clean grains.
Direct sowings are made in spring, about 14 pounds of seed
per acre being required for broadcast sowings ; it receives a
covering of about one-tbird of an incb, and it germinates
after tbree or four weeks, if the seed is fresh ; okl seed
germinates very irreguhirly. Direct sowings are rarely made.
In nurseries the seed may be sown broadcast or in drills.
British nurserymen generally sow broadcast, about one pound
of seed per 100 square feet of seed-bed. The seedlings are
pricked out when one year old, or not at all. Plantings are
done with two-year-old seedlings, or with transplants after
they have stood one or two years in the nursery lines. Older
plants are rarely used. In Britain the method of planting is
generally notching ; pit planting is also done. Planting must
be done early in spring, or in autumn, as the larch sprouts
very early. The i)lants need not be placed closer than
4 feet apart.
Owing to its great light requirement the tree is not really
suited for natural regeneration by seed ; but if this is
attempted, the mother trees must be placed far apart, or
the area clear cut in strips, allowing the seed to fall on them
from adjoining woods. The method is only successful under
favourable circumstances. At any rate, a second seed year
should not be awaited, but all areas not stocked by the first
seed year should be planted up.
Owing to the great damage by Pcziza {Dasijscypha) Will-
hnnmii, the larch should in future be introduced singly into
other woods, especially beech woods.
'/. Tendinii.
FcrtiUtif of Soil. — Pure woods protect the soil sufficiently
only for about 25 to 30 years ; hence they should be under-
planted.
External Dangers. — In its natural home larch is hardy ; it
suffers little from late frosts, and also not much from drought.
•380 NOTKS ON LtPilTISH I'OKEST TREES.
The damage done by snow and rime is of moderate extent,
and the tree is very storm firm. In Britain it is not so storm
firm, especially if the soil should be saturated with water at
the time of a gale ; it also suffers somewhat more from late
frosts, because it sprouts much earlier.
Roebuck and deer do a great deal of damage lo larch by
injuring the bark, which is also peeled by rabbits. Squirrels
peel the top shoots. Hence the tree should be protected
against these animals by fencing and shooting.
Larch is much exposed to attacks by insects and fungi,
and these dangers are much greater in countries where it has
been artificially introduced. The larch is especially attacked
by minute moths, as Coleopliora laricclla, which hollows out
the needles, and Aniyreathia hev'ujatcUa, and several Tort rices.
The " larch-bug," Cliermes larUis, is very injurious. Numerous
bark-beetles live in the larch in common with other conifers.
Fungi. — PJu/fophthora omnicora kills the young seedlings.
Peziza {Dnsyscypha) Willhommii eats away the bark and cam-
bium, causing canker ; this disease has now become so prevalent
in many parts of Britain that the further production of the tree
has become altogether problematic. AgaricuH i}idlcu>i kills the
roots ; Trametes pini destroys the wood, leaving white spots ;
Polyporus salphiireus produces red rot.
Pruniufj. — The larch stands [)runing well, but the operation
affords an entrance for fungi, especially Peziza Willkommii ;
hence it should be done very sparingly. It is much better to
grow the larch so that the lower branches die oft' and fall
naturally.
Tliiiniinf/s must begin earl}-. They should be light until
the time has come for miderplanting, when they must be
heavy, leaving only healthy, vigorous, well formed trees
as the overwood which are to develop into large timber trees.
Of late the Japanese larch, Ltirix le))f<>Ie})is, has been much
reconniiended. Up to dale lliei-e is no proof whatever that it
will do better than tlie European lan-li. On the contrary,
there are indications that the latter catches u}) and pass(!S the
THE BOFGLAS FIE. 381
former in height at the age of about 25 or 30 years, and that
it is less branchy and straighter at that age. Again, canker
has ah-eady been observed on the Japanese larch, so that it is
impossible to say whether it will be more resistant against
disease than the European larch.
21. Douglas Fir — Pseudotsmia Douglasli (Carr).
(The "Red Fir or Oregon Pine of North America.)
The Douglas fir is a native of the western part of North
America, where it is found between latitudes 31° and 55°
and longitudes 104° and 130°.* It is considered the most
valuable forest tree of North America, owing to its rapid
growth, great dimensions and the excellence of its timber.
The latter is said to be equal to that of larch, while trees of
over 300 feet in height, with a corresponding diameter, are
said to exist. The tree was introduced into Britain in 1826
(Brown), and the experience so far gained singles it out as a
most promising timber tree for this country ; hence it was
considered desirable to add it to the present list.
The sylvicultural data at present available are not yet
sufficient to give a complete set of notes on the treatment of
the Douglas fir in Britain. Numerous experimental plantations
have been established in this country and on the Continent,
some of which are upwards of 40 years old (apart from single
trees or groups of greater age), and the following remarks are
based upon observations made in these, and on the informa-
tion supplied by Dr. H. Mayr, in his interesting work on " The
Forests of North America," 1890. t
a. Locality.
The Douglas fir reaches its greatest perfection on the slopes
and in the moist valleys of the Cascade Mountains in Oregon
* According to Professor C. S. t>argent.
t Dr. Mayr, a Bavarian Forest Officer, and now Professor of Forestry at
Munich, visited Nortli America twice since 1885, and spent altogether seven
months in its forests. He largelv utilized Professor Sargent's investigations.
882 NOTES ON BRITISH FOREST TREES.
and Washington, and in the coast districts of British Cokimbia,
a[)]ji-oximately bet^Yeen the 40th and 50th degrees of hititnde.
These territories have an annual rainfall of about 65 inches,
with a moist atmosphere, the climate being comparativel}'
mild. As regards soil, it appears that a deep, fertile, and at
least fresh, sandy loam suits the tree best. Under the most
favourable conditions it here attains a height of about
300 feet. It seems to avoid stiff clay and also poor, sandy
soils as well as chalk soils.
In the mountains of Montana, with a comparatively small
rainfall of about 24 inches and a dry atmosphere, the Douglas
fir reaches, if grown on the most suitable soil, a height not
exceeding 150 feet, which however is also the limit in the
coast districts, if the tree is grown on moderately fertile soil.
On poor soil, even in the latter districts, the maximum height
is frequently found to be 100 feet or even less.
From these data it appears that the Douglas iir, if it is to
do well, requires a moist climate and a deep, fertile, fresh or
moist soil, especially light loam. It accommodates itself to a
different climate and soil, but the heiglit growth falls off in
due proportion.
In its natural home the Douglas fir is said to be very hardy ;
in Montana it is exposed to great winter cold, and is found
growing without shelter. In the coast districts, with a long
growing season, it is said to suffer from early frost. In
Britain it has on the whole been found hardy.
Two distinct varieties are now recognised, known in
Britain as the Pacitic or fast growing variety, and the
Colorado or slower growing variety. The former is liable to
suffer from early autumn frosts in the north of England
and in Scotland ; hence its cultivation can be recommended
for the south and west of England and Ireland. The
Colorado variety is hardier, and is, therefore, preferred for
cultivation in the north. It has, however, been observed
that it sprouts earlier in spring, and is, ilKu-ofore. soniowhat
more exposed to damage by spring frosts.
THE DOUGLAS FIR. 8S.8
To what extent the Douglas fir ma}' be considered storm firm
in Europe will depend on further experience ;, in Scotland
many trees only 30 years old, grown in fairly crowded
plantations, have been throwai. In exposed localities the
leading shoots suffer to an excessive extent.
German foresters seem to consider the Douglas fir to be a
moderately light demanding species. The author is more
inclined to class it as a moderate shade bearer, standing near
spruce, or still nearer the Himalayan deodar.
h. Sliape and Developmeni.
The Douglas fir develops a straight undivided stem, except
that in some localities the first 6 feet from the ground are
curved. Grown in the open the crown covers the whole stem
and comes down almost to the ground; the stems of such trees
are very tapering. If grown in crowded woods in its natural
home, the lowest portion of the stem is exceptionally stout ;
the crown forms a sharp cone confined to the upper half of
the stem, w^iilst the bole is described as of a remarkably
cylindrical shape, at least as much as that of the European
silver fir. A regular wood* which the author examined in
1888 was 32 years old ; in this all the trees were excessively
tapering, giving a form factor t of *39 for timber only (over
3 inches diameter at the thin end). Since then the form
factor has risen to "tt-l.
The growth of the Douglas fir is exceedingly fast. At the
same time it varies enormously according to climate and soil.
According to Mayr, a wood 80 years old and grown under the
most favourable conditions showed an average height of about
133 feet, or an average annual height growth of nearly 20 inches.
The Taymount plantation shows an average height growth of
about 22 inches.
In Montana, according to Mayr, the Douglas fir shoM'S a
height growth of about 10 inches on an annual average, or
* Taymount. on the estate of the Earl of Mansfield. Scotland ; area = 8 acres,
t For " Form Factor" see Volume III.
•SSI. NOTKS ON lUtTTTSH FOKKST TREES.
about one-half of tliat in tlie coast districts. Fncler any
circumstances, as far as experience goes at present, the
Douglas iir, if planted in suitable localities, outgrows all
European limber trees. The tree also attains a great diameter :
the average diameter of mature trees, 200 feet high, in the coast
districts is given as about () feet, and in Montana as about
2^ feet. It follows that the volume increment is very great.
Experience up to date shows that it exceeds the fastest growing
of European trees to a considerable extent, as the following
data will show : — The Taymount plantation yielded the
following data in 1R88:—
Age = 82 years (including the age of the plants when
put out).
Number of trees per acre . . . = 202
Mean diameter =12 inches
Mean height ..... =60 feet
Volume, excluding all material under 8
inches diameter . . . = 3,738 cubic feet
Mean annual production . . . =117 ,, ,,
Sample areas measured in the same wood l)y Mr. Pitcaithley
in 1903 showed the following results : —
Age -47 years
Numl)er of trees per acre . . . = 202
Mean diameter =15 inches
Mean height =79 feet
Volume = 10,218 cubic feet
Mean annual production . . . =217 ,, .,
The plantation was too heavily thinned in 1887. since when
no further thinning had been made.
The Taymount plantation consists of tlie Pacific variety.
The Colorado variety is not likely to yield anything lil