Crops and Methods for Soil Improvement
by Alva Agee · English · Gutenberg #23682 · 336,646 chars · public domain (US)
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Title: Crops and Methods for Soil Improvement
Author: Alva Agee
Release date: December 2, 2007 [eBook #23682]
Language: English
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Produced by Steven Giacomelli and the Online Distributed
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CROPS AND METHODS FOR SOIL IMPROVEMENT
THE MACMILLAN COMPANY
NEW YORK . BOSTON . CHICAGO
DALLAS . SAN FRANCISCO
MACMILLAN & CO., Limited
LONDON . BOMBAY . CALCUTTA
MELBOURNE
THE MACMILLAN CO. OF CANADA, Ltd.
TORONTO
[Illustration: Alfalfa and Corn in Indiana.]
CROPS AND METHODS
FOR SOIL IMPROVEMENT
By
ALVA AGEE, M.S.
HEAD OF DEPARTMENT OF AGRICULTURAL EXTENSION
ACTING DEAN AND DIRECTOR OF THE SCHOOL OF
AGRICULTURE AND EXPERIMENT STATION OF
THE PENNSYLVANIA STATE COLLEGE
_ILLUSTRATED_
New York
THE MACMILLAN COMPANY
1912
_All rights reserved_
Copyright, 1912,
By THE MACMILLAN COMPANY.
Set up and electrotyped. Published November, 1912.
Norwood Press
J. S. Cushing Co.--Berwick & Smith Co.
Norwood, Mass., U.S.A.
CONTENTS
CHAPTER I
PAGES
INTRODUCTION 1-11
In lieu of preface 1
Natural strength of land 2
Plant constituents 2
Organic matter 4
Drainage 6
Lime 7
Crop-rotation 8
Fertilizers 9
Tillage 10
Control of soil moisture 11
CHAPTER II
THE NEED OF LIME 12-22
The unproductive farm 12
Soil acidity 13
The rational use of lime 14
Where clover is not wanted 16
Determining lime requirement 17
The litmus-paper test 19
A practical test 20
Duration of effect 21
CHAPTER III
APPLYING LIME 23-35
Forms of lime 23
Definitions 24
The kind to apply 26
The fineness of limestone 27
Hydrated lime 27
Stone-lime 28
Ashes 30
Marl 31
Magnesian lime 31
Amount per acre 32
Time of application 34
CHAPTER IV
ORGANIC MATTER 36-45
Office of organic matter 36
The legumes 38
Storing nitrogen 39
The right bacteria 41
Soil inoculation 42
Method of inoculation 43
CHAPTER V
THE CLOVERS 46-58
Red clover 46
Clover and acid soils 47
Methods of seeding 48
Fertility value 49
Taking the crops off the land 51
Physical benefit of the roots 52
Used as a green manure 52
When to turn down 53
Mammoth clover 54
Alsike clover 55
Crimson clover 56
CHAPTER VI
ALFALFA 59-70
Adaptation to eastern needs 59
Fertility and feeding value 60
Climate and soil 61
Free use of lime 62
Inoculation 62
Fertilization 63
A clean seed-bed 64
Varieties 65
Clean seed 65
The seeding 66
Seeding in August 67
Subsequent treatment 68
CHAPTER VII
GRASS SODS 71-79
Value of sods 71
Prejudice against timothy 72
Object of sods 74
Seeding with small grain 75
Seeding in rye 76
Good soil conditions 77
CHAPTER VIII
GRASS SODS (_Continued_) 80-89
Seeding in late summer 80
Crops that may precede 81
Preparation 83
The weed seed 84
Summer grasses 85
Sowing the seed 85
Deep covering 86
Seed-mixtures 88
CHAPTER IX
SODS FOR PASTURES 90-97
Permanent pastures 90
Seed-mixtures 91
Blue-grass 91
Timothy 92
Red-top 92
Orchard grass 93
Other seeds 93
Yields and composition of grasses 93
Suggested mixtures for pastures 94
Renewal of permanent pastures 96
Destroying bushes 96
Close grazing 97
CHAPTER X
THE COWPEA 98-107
A southern legume 98
Characteristics 99
Varieties 99
Fertilizing value 100
Affecting physical condition 101
Planting 101
Inoculation 103
Fertilizers 103
Harvesting with livestock 104
The cowpea for hay 104
As a catch crop 106
CHAPTER XI
OTHER LEGUMES AND CEREAL CATCH CROPS 108-119
The soybean 108
Fertility value 109
Feeding value 109
Varieties 110
The planting 111
Harvesting 112
The Canada pea 113
Vetch 113
Sweet clover 115
Rye as a cover crop 116
When to plow down 117
Buckwheat 118
Oats 119
CHAPTER XII
STABLE MANURE 120-128
Livestock farming 120
The place for cattle 121
Sales off the farm 122
The value of manure 124
The content of manure 125
Relative values 126
Amount of manure 127
Analysis of manure 128
CHAPTER XIII
CARE OF STABLE MANURE 129-138
Common source of losses 129
Caring for liquid manure 130
Use of preservatives 131
Spreading as made 132
The covered yard 133
Harmless fermentation 135
Rotted manure 135
Composts 136
Poultry manure 137
CHAPTER XIV
THE USE OF STABLE MANURE 139-148
Controlling factors 139
Direct use for corn 140
Effect upon moisture 141
Manure on grass 142
Manure on potatoes 143
When to plow down 144
Heavy applications 144
Reenforcement with minerals 145
Durability of manure 147
CHAPTER XV
CROP-ROTATIONS 149-158
The farm scheme 149
Value of rotation 150
Selection of crops 151
An old succession of crops 152
Corn two years 153
The oat crop 154
Two crops of wheat 154
The clover and timothy 154
Two legumes in the rotation 155
Potatoes after corn 156
A three-years' rotation 157
Grain and clover 158
Potatoes and crimson clover 158
CHAPTER XVI
THE NEED OF COMMERCIAL FERTILIZERS 159-170
Loss of plant-food 159
Prejudice against commercial fertilizers 160
Are fertilizers stimulants? 161
Soil analysis 162
Physical analysis 163
The use of nitrogen 164
Phosphoric-acid requirements 165
The need of potash 166
Fertilizer tests 167
Variation in soil 168
CHAPTER XVII
COMMERCIAL SOURCES OF PLANT-FOOD 171-187
Acquaintance with terms 171
Nitrate of soda 171
Sulphate of ammonia 178
Dried blood 173
Tankage 174
Fish 175
Animal bone 175
Raw bone 177
Steamed bone 178
Rock-phosphate 178
Acid phosphate 180
Basic slag 183
Muriate of potash 184
Sulphate of potash 185
Kainit 185
Wood-ashes 185
Other fertilizers 186
Salt 186
Coal-ashes 187
Muck 187
Sawdust 187
CHAPTER XVIII
PURCHASING PLANT-FOOD 188-197
Necessity of purchase 188
Fertilizer control 189
Brand names 191
Statement of analysis 191
Valuation of fertilizers 193
A bit of arithmetic 194
High-grade fertilizers 196
CHAPTER XIX
HOME-MIXING OF FERTILIZERS 198-208
The practice of home-mixing 198
Effectiveness of home-mixing 198
Criticisms of home-mixing 199
The filler 202
Ingredients in the mixture 203
Materials that should not be combined 207
Making a good mixture 207
Buying unmixed materials 208
CHAPTER XX
MIXTURES FOR CROPS 209-219
Composition of plant not a guide 209
The multiplication of formulas 209
A few combinations are safest 210
Amount of application 211
Similarity of requirements 213
Maintaining fertility 215
Fertilizer for grass 216
All the nitrogen from clover 218
Method of applying fertilizers 218
An excess of nitrogen 219
CHAPTER XXI
TILLAGE 220-229
Desirable physical condition of the soil 220
The breaking-plow 221
Types of plows 221
Subsoiling 223
Time of plowing 223
Method of plowing 224
The disk harrow 225
Cultivation of plants 227
Controlling root-growth 227
Elimination of competition 228
Length of cultivation 229
CHAPTER XXII
CONTROL OF SOIL MOISTURE 230-236
Value of water in the soil 230
The soil a reservoir 231
The land-roller 232
The plank-drag 233
The mulch 233
Mulches of foreign material 234
Plowing straw down 235
The summer-fallow 235
The modern fallow 236
CHAPTER XXIII
DRAINAGE 237-246
Underdrainage 237
Counting the cost 238
Where returns are largest 239
Material for the drains 239
The outlet 240
Locating main and branches 240
The laterals 241
Size of tile 241
Kind of tile 242
The grade 243
Establishing a grade 243
Cutting the trenches 244
Depth of trenches 245
Connections 245
Permanency desired 246
ILLUSTRATIONS
Alfalfa and Corn in Indiana _Frontispiece_
Facing Page
A Good Crop for a Poor Soil 4
Red Clover on Limed and Unlimed Land 20
Turning down Organic Matter with a Gang Plow 36
Red Clover on the Farm of P. S. Lewis & Son,
Pt. Pleasant, W. Va. 51
Alfalfa on the Ohio State University Farm 61
Curing Alfalfa at the Pennsylvania
Experiment Station 68
A Heavy Grass Sod in New York 73
Good Pasture Land in Chester County, Pa. 90
Sheep on a New York Farm 96
The Cowpea Seeded at the Last Cultivation of Corn
in the Great Kanawha Valley, W. Va. 106
Texas Calves on an Ohio Farm 121
In the Fertile Miami Valley, Ohio 126
Concrete Stable Floors 131
Corn in the Ohio Valley 140
Penn's Valley, Pennsylvania 151
In the Shenandoah Valley 155
Plat Experiments 167
In the Lebanon Valley, Pennsylvania 189
On the Productive Farm of Dr. W. I. Chamberlain
in Northwestern Ohio 210
Deep Tillage 222
Making an Earth Mulch in a New York Orchard 233
Drain Tile 239
The Lure of the Country 246
CROPS AND METHODS FOR SOIL IMPROVEMENT
CHAPTER I
INTRODUCTION
In Lieu of Preface.--This book is not a technical treatise and is
designed only to point out the plain, every-day facts in the natural
scheme of making and keeping soils productive. It is concerned with the
crops, methods, and fertilizers that favor the soil. The viewpoint, all
the time, is that of the practical man who wants cash compensation for
the intelligent care he gives to his land. The farming that leads into
debt, and not in the opposite direction, is poor farming, no matter how
well the soil may prosper under such treatment. The maintenance and
increase of soil fertility go hand in hand with permanent income for
the owner when the science that relates to farming is rightly used.
Experiment stations and practical farmers have developed a dependable
science within recent years, and there is no jarring of observed facts
when we get hold of the simple philosophy of it all.
Natural Strength of Land.--Nearly all profitable farming in this
country is based upon the fundamental fact that our lands are
storehouses of fertility, and that this reserve of power is essential
to a successful agriculture. Most soils, no matter how unproductive
their condition to-day, have natural strength that we take into
account, either consciously or unconsciously. Some good farm methods
came into use thousands of years ago. Experience led to their
acceptance. They were adequate only because there was natural strength
in the land. Nature stored plant-food in more or less inert form and,
as availability has been gained, plants have grown. Our dependence
continues.
Plant Constituents.--There are a few technical terms whose use cannot
be evaded in the few chapters on the use of lime and fertilizers. A
plant will not come to maturity unless it can obtain for its use
combinations of ten chemical elements. Agricultural land and the air
provide all these elements. If they were in abundance in available
forms, there would be no serious soil fertility problem. Some of their
names may not interest us. Six or seven of these elements are in such
abundance that we do not consider them. A farmer may say that when a
dairy cow has luxuriant blue-grass in June, and an abundance of pure
water, her wants are fully met. He omits mention of the air because it
is never lacking in the field. In the same way the land-owner may
forget the necessity of any kind of plant-food in the soil except
nitrogen, phosphoric acid, potash, and lime. Probably the lime is very
rarely deficient as a food for plants, and will be considered later
only as a means of making soils friendly to plant life.
Nitrogen, phosphoric acid, and potash are the three substances that may
not be in available form in sufficient amount for a growing crop. The
lack may be in all three, or in any two, or in any one, of these plant
constituents. The natural strength of the soil includes the small
percentage of these materials that may be available, and the relatively
large stores that nature has placed in the land in inert form as a
provision against waste.
The thin covering of the earth that is known as the soil is
disintegrated rock, combined with organic matter. The original rock
"weathered," undergoing physical and chemical change. A long period of
time was required for this work, and for the mixing and shifting from
place to place that have occurred. Organic matter has been a factor in
the making of soils, and is in high degree a controlling one in their
production of food.
Organic Matter.--Nature is resourceful and is constantly alert to
repair the wastes and mistakes of man. We may gain fundamental truth
about soil fertility through observance of her methods in restoring
land to a fertile condition. Our best success comes only when we work
with her. When a soil has been robbed by man, and has been abandoned on
account of inability to produce a profitable crop, the first thing
nature does is to produce a growth of weeds, bushes, briers, or aught
else of which the soil chances to have the seeds. It is nature's effort
to restore some organic matter--some humus-making material--to the
nearly helpless land. Vegetable matter, rotting on and in the soil, is
the life-giving principle. It unlocks a bit of the great store of inert
mineral plant-food during its growth and its decay. It is a solvent.
The mulch it provides favors the holding of moisture in the soil, and
it promotes friendly bacterial action. The productive power of most
farming land is proportionate to the amount of organic matter in it.
The casual observer, passing by farms, notes the presence or absence of
humus-making material by the color and structure of the soil, and
safely infers corresponding fertility or poverty. Organic matter is the
life of the soil.
[Illustration: A good crop for a poor soil.]
A great percentage of the food consumed by Europe and the Americas
continues to come out of nature's own stores in the soil, organic and
inorganic, without any assistance by man except in respect to selection
of seeds, planting, and tillage. The percentage grows less as the store
of original supplies grows less and population increases. Our science
has broadened as the need has grown greater. We have relatively few
acres remaining in the United States that do not require intelligent
treatment to insure an adequate supply of available plant-food. The
total area that has fallen below the line of profitable productiveness
is large. Other areas that never were highly productive must supplement
the lands originally fertile in order that human needs may be met.
When soils have been robbed through the greed of man, nature is
handicapped in her effort to restore fertility by the absence of the
best seeds. Man's intelligent assistance is a necessity. Successful
farming involves such assistance of nature that the percentage of
vegetable matter in the soil shall be made high and kept high. There
must be such selection of plants for this purpose that the organic
matter will be rich in fertility, and at the same time their growth
must fit into a scheme of crop production that can yield profit to the
farmer. Soils produce plants primarily for their own needs. It is a
provision of nature to maintain and increase their productive power.
The land's share of its products is that part which is necessary to
this purpose. Skill in farming provides for this demand of the soil
while permitting the removal of a large amount of animal food within
the crop-rotation. Lack of skill is responsible for the depleted
condition of soils on a majority of our farms. The land's share of the
vegetation it has produced has been taken from it in large measure, and
no other organic matter has been given it in return. Its mineral store
is left inert, and the moisture supply is left uncontrolled.
Helplessness results.
Drainage.--Productive soils are in a condition to admit air freely. The
presence of air in the soil is as necessary to the changes producing
availability of plant-food as it is to the changes essential to life in
the human body. A water-logged soil is a worthless one in respect to
the production of most valuable plants. The well-being of soil and
plants requires that the level of dead water be a considerable distance
below the surface.
When a soil has recently grown trees, the rotting stump roots leave
cavities in the subsoil that permit the removal of some surplus water,
and the rotted wood and leaves that give distinctive character to new
land are absorbents of such water. As land becomes older, losing
natural means of drainage and the excellent physical condition due to
vegetable matter in it, the need of drainage grows greater. The
tramping of horses in the bottoms of furrows made by breaking-plows
often makes matters worse. The prompt removal of excessive moisture by
drains, and preferably by underdrains, is essential to profitable
farming in the case of most wet lands. The only exception is the land
on which may be grown the grasses that thrive fairly well under moist
conditions.
Lime.--The stores of lime in the soil are not stable. The tendency of
lime in most of the states between the Missouri River and the Atlantic
seaboard is to get out of the soil. There is no evidence that lime is
not in sufficient quantity in most soils to feed crops adequately, but
within recent years we have learned that vast areas do not contain
enough lime in available form to keep the soil from becoming acid. Some
soils never were rich in lime, and these are the first to show evidence
of acidity. In our limestone areas, however, acid soil conditions are
developing year by year, limiting the growth of clover and affecting
the yields of other crops.
The situation is a serious one just in so far as men refuse to
recognize the facts as they exist, and permit the limiting of crop
yields, and consequently of incomes, through the presence of harmful
acids. The natural corrective is lime, which combines with the acid and
leaves the soil friendly to all plant life and especially to the
clovers and other legumes that are necessary to profitable farming.
Nature is largely dependent upon man's assistance in the correction of
soil acidity.
Crop-rotation.--A good crop-rotation favors high productiveness. One
kind of crop paves the way nicely for some other one. The land can be
occupied by living plants without any long intermissions. Organic
matter can be supplied without the use of an undue portion of the time.
The stores of plant-food throughout all the soil are more surely
reached by a variety of plants, differing in their habits of
root-growth. The injury from disease and insects is kept down to a
minimum. There is better distribution of the labor required by the
farm, and neglect of crops at critical times is escaped. The
maintenance of fertility is dependent much upon the use of a legume
that will furnish nitrogen from the air. A permanently successful
agriculture in our country must be based upon the use of legumes, and
crop-rotations would be demanded for this reason alone if none other
existed.
Fertilizers.--When a crop is fed to livestock, and all the manure is
returned to the land that produced the crop without loss by leaching or
fermentation, there is a return to the land of four fifths of the
fertility, and a good form of organic matter is supplied. A portion of
the crops cannot be fed upon the farm, or otherwise the human race
would have only animal products for food. The welfare of the people
demands that a vast amount of the soil's crops be sold from the farms
producing them. This brings about a dependence upon the natural stores
of plant-food in the soil, which become available slowly, and upon
commercial fertilizers.
There has been a disposition on the part of many farmers to regard
fertilizers only as stimulants, due to the irrational use of certain
materials, but a good commercial fertilizer is a carrier of some or all
of the necessary elements that we find in stable manures. They may
carry nitrogen, phosphoric acid, or potash,--any one or two or the
three,--and the three are the constituents that usually are lacking in
available forms in our soils. Examples of the best modern skill in
farming may be found in the rational selection and use of commercial
fertilizers.
Tillage.--Man's ability to assist nature in the work of production
finds a notable illustration in the matter of tillage. Its purpose is
to provide right physical condition of the soil for the particular
class of plants that should be produced, while destroying the
competition of other plants that are for the time only weeds. Most
soils become too compact when left unstirred. The air cannot enter
freely, plant-roots cannot extend in every direction for food, the
water from rains cannot enter easily, there is escape of the moisture
in the ground, and weathering of the soil proceeds too slowly. The
methods used in plowing, harrowing, and later cultivations fix the
productive power of a soil for the season in large measure.
Control of Soil Moisture.--The water in the soil is a consideration
that has priority over plant-food in the case of agricultural land. The
natural strength of the soil is sufficient to give some return to the
farmer in crops if the moisture content is right throughout the season.
The plant cannot feed unless water is present; the process of growth
ceases in the absence of moisture. One purpose of plowing is to
separate the particles of soil to a good depth so that water-holding
capacity may be increased. When the soil is compact, it will absorb and
hold only a very limited amount of moisture. We harrow deeply to
complete the work of the plow, and the roller is used to destroy all
cavities of undue size that would admit air too freely and thus rob the
land of its water. Later cultivations may be given to continue the
effect of the plow in preventing the soil from becoming too compact,
but usually should be required only to make a loose mulch that will
hold moisture in the ground, and to destroy the weeds that would
compete with the planted crop for water, food, and sunshine.
CHAPTER II
THE NEED OF LIME
The Unproductive Farm.--When a soil expert visits an unproductive farm
to determine its needs, he gives his chief attention to four possible
factors in his problem: lack of drainage, of lime, of organic matter,
and of available plant-food. His first concern regards drainage. If the
water from rains is held in the surface by an impervious stratum
beneath, it is idle to spend money in other amendments until the
difficulty respecting drainage has been overcome. A water-logged soil
is helpless. It cannot provide available plant-food, air, and warmth to
plants. Under-drainage is urgently demanded when the level of dead
water in the soil is near the surface. The area needing drainage is
larger than most land-owners believe, and it increases as soils become
older. On the other hand, the requirements of lime, organic matter, and
available plant-food are so nearly universal, in the case of
unproductive land in the eastern half of the United States, that they
are here given prior consideration, and drainage is discussed in
another place when methods of controlling soil moisture are described.
The production of organic matter is so important to depleted soils, and
is so dependent upon the absence of soil acidity, that the right use of
lime on land claims our first interest.
Soil Acidity.--Lime performs various offices in the soil, but farmers
should be concerned chiefly about only one, and that is the destruction
of acids and poisons that make the soil unfriendly to most forms of
plant life, including the clovers, alfalfa, and other legumes. Lime was
put into all soils by nature. Large areas were originally very rich in
lime, while other areas of the eastern half of the United States never
were well supplied. Within the last ten years it has been definitely
determined that a large part of this vast territory has an actual lime
deficiency, as measured by its inability to remain alkaline or "sweet."
Many of the noted limestone valleys show marked soil acidity. There has
been exhaustion of the lime that was in a state available for union
with the acids that constantly form in various ways. The area of soil
thus deficient grows greater year by year, and it can be only a matter
of time when nearly all of the eastern half of this country will have
production limited by this deficiency unless applications of lime in
some form are made. When owners of soil that remains rich in lime do
not accept this statement, no harm results, as their land does not need
lime. On the other hand are tens of thousands of land-owners who do not
recognize the need of lime that now exists in their soils, and suffer a
loss of income which they would attribute to other causes.
Irrational Use of Lime.--Some refusal to accept the facts respecting
soil acidity and its means of correction is due to a prejudice that was
created by an unwise use of lime in the past. Owners of stiff limestone
soils learned in an early day that a heavy application of caustic lime
would increase crop production. It caused such flocculation of the fine
particles in their stiff soils that physical condition was improved,
and it made the organic matter in the soil quickly available as
plant-food. The immediate result was greater crop-producing power in
the soil, and dependence upon lime as a fertilizer resulted. The
vegetable matter was used up, some of the more available mineral
plant-food was changed into soluble forms, and in the course of years
partial soil exhaustion resulted. The heavy applications of lime,
unattended by additions of organic matter in the form of clover sods
and stable manure, produced a natural result, but one that was not
anticipated by the farmers. The prejudice against the use of lime on
land was based on the effects of this irrational practice.
There are land-owners who are not concerned with present-day knowledge
regarding soil acidity because they cannot believe that it has any
bearing upon the state of their soils. They know that clover sods were
easily produced on their land within their remembrance, and that their
soils are of limestone origin. As the clovers demand lime, these two
facts appear to them final. The failures of the clovers in the last ten
or twenty years they incline to attribute to adverse seasons, poor
seed, or the prevalence of weed pests. They do not realize that much
land passes out of the alkaline class into the acid one every year. The
loss of lime is continuous. Exhaustion of the supply capable of
combining with the harmful acids finally results, and with the
accumulation of acid comes partial clover failure, a deficiency in rich
organic matter, a limiting of all crop yields, and an inability to
remain in a state of profitable production.
Lime deficiency and its resulting ills would not exist as generally as
is now the case if the application of lime to land were not expensive
and disagreeable. These are deterrent features of wide influence. There
continues hope that the clover will grow successfully, as occasionally
occurs in a favorable season, despite the presence of some acid. The
limitation of yields of other staple crops is not attributed to the
lack of lime, and the proper soil amendment is not given to the land.
Where Clover is not Wanted.--The ability to grow heavy red clover is a
practical assurance that the soil's content of lime is sufficiently
high. When clover fails on account of a lime deficiency, the work of
applying lime may not be escaped by a shift in the farm scheme that
permits the elimination of clover. The clover failure is an index of a
condition that limits the yields of all staple crops. The lack of lime
checks the activity of bacteria whose office it is to prepare
plant-food for use. The stable manure or sods decompose less readily
and give smaller results. Soil poisons accumulate. Mineral plant-food
in the soils becomes available more slowly. Physical condition grows
worse.
The limitations of the value of manure and commercial fertilizers
applied to land that has a lime deficiency have illustration in an
experiment reported by the Cornell station:
The soil was once a fertile loam that had become very poor. A part was
given an application of lime, and similar land at its side was left
unlimed. The land without lime and fertilizer of any kind made a yield
of 1824 pounds of clover hay per acre. A complete fertilizer on the
unlimed land made the yield 2235 pounds, and 15 tons of manure on the
unlimed land made the yield 2091 pounds.
Where lime had been applied, the unfertilized land yielded 3852 pounds
per acre, the fertilized, 4085 pounds, and the manured, 4976 pounds.
The manure and fertilizer were nearly inactive in the acid soil. The
lime enabled the plants to obtain benefit from the plant-food.
Determining Lime Requirement.--It is wasteful to apply lime on land
that does not need it. As has been said, the man who can grow heavy
clover sods has assurance that the lime content of his soil is
satisfactory. This is a test that has as much practical value as the
analysis of a skillful chemist. The owner of such land may dismiss the
matter of liming from his attention so far as acidity is concerned,
though it is a reasonable expectation that a deficiency will appear at
some time in the future. Experience is the basis of such a forecast.
Just as coal was stored for the benefit of human beings, so was lime
placed in store as a supply for soils when their unstable content would
be gone.
The only ones that need be concerned with the question of lime for
soils are those who cannot secure good growths of the clovers and other
legumes. Putting aside past experience, they should learn whether their
soils are now acid. Practical farmers may judge by the character of the
vegetation and not fail to be right nine times out of ten. Where land
has drainage, and a fairly good amount of available fertility, as
evidenced by growths of grass, a failure of red clover leads
immediately to a strong suspicion that lime is lacking. If alsike
clover grows more readily than the red clover, the probability of
acidity grows stronger because the alsike can thrive under more acid
soil conditions than can the red. Acid soils favor red-top grass rather
than timothy. Sorrel is a weed that thrives in both alkaline and acid
soils, and its presence would not be an index if it could stand
competition with clover in an alkaline soil. The clover can crowd it
out if the ground is not too badly infested with seed, and even then
the sorrel must finally give way. Where sorrel and plantain cover the
ground that has been seeded to clover and grass, the evidence is strong
that the soil conditions are unfriendly to the better plants on account
of a lime deficiency. The experienced farmer who notes the inclination
of his soil to favor alsike clover, red-top, sorrel, and plantain
should infer that lime is lacking. If doubt continues, he should make a
test.
The Litmus-paper Test.--A test of fair reliability may be made with
litmus paper. A package of blue litmus paper can be bought for a few
cents at any drug store. This paper will turn pink when brought into
contact with an acid, and will return to a blue if placed in
lime-water. A drop of vinegar on a sheet of the paper will bring an
immediate change to pink. If the pink sheet be placed in lime-water,
the effect of the lime in correcting the acidity will be evidenced by
the return in color to blue.
To test the soil, a sample of it may be put into a basin and moistened
with rain-water. Several sheets of the blue litmus paper should be
buried in the mud, care being used that the hands are clean and dry.
When one sheet is removed within a few seconds and rinsed with
rain-water, if any pink shows, there is free acid present. Another
sheet should be taken out in five minutes. The rapidity with which the
color changes, and the intensity of the color, are indicative of the
degree of acidity, and aid the judgment in determining how much lime
should be used. If a sheet of the paper retains its blue color in the
soil for twenty minutes, there probably is no lime deficiency. The test
should be made with samples of soil from various parts of the field,
and they should be taken beneath the surface. One just criticism of
this test is that while no acidity may be shown, the lime content may
be too low for safety.
[Illustration: Red clover on limed and unlimed land.]
A Practical Test.--The importance of alkalinity in soils is so great,
and the prevalence of acidity has such wide-spread influence to-day,
limiting the value of the clovers on a majority of our farms, that a
simple and more convincing test is suggested here. Every owner of land
that is not satisfactorily productive may learn the state of his soil
respecting lime requirement at small expense. When a field is being
prepared for seeding to the grain crop with which clover will be sown,
a plat containing four square rods should be measured off, and
preferably this should be away from the border to insure even soil
conditions. A bushel of lump-lime, weighing eighty pounds, should be
slaked and evenly distributed over the surface of the plat of ground.
It can be broadcasted by hand if a spreader is not available, and mixed
with the surface soil while in a powdered state. The plat of ground
should be left as firm as the remainder of the field, so that all
conditions may be even for the test. The appearance of the clover the
following year will determine whether lime was needed or not. There is
no reason why any one should remain in doubt regarding the lime
requirement of his fields. If income is limited by such a cause, the
fact should be known as soon as possible.
Duration of Effect.--Soil acidity is not permanently corrected by a
lime application. The original supply failed to prove lasting, and the
relatively small amount given the land in an application will become
exhausted. The duration depends upon the degree of acidity, the nature
of the soil and its crops, and the size of the application. Experiments
at the Pennsylvania experiment station have shown that an application
only in sufficient amount to correct the existing acidity at the time
of application will not maintain an alkaline condition in the soil,
even for a few months. There must be some excess at hand to unite with
acids as formed later in the crop-rotation, or limings must be given at
short intervals of time to maintain alkaline conditions.
Experience causes us to assume that enough lime should be applied at
one time to meet all requirements for a single crop-rotation of four,
five, or six years, and, wherever lime is cheap, the unpleasant
character of the labor inclines one to make the application in
sufficient amount to last through two such rotations. It is a
reasonable assumption, however, that more waste results from the
heavier applications at long intervals than from light applications at
short intervals. In any event need will return, and soil acidity will
again limit income if applications do not continue to be made.
CHAPTER III
APPLYING LIME
Forms of Lime.--There is unnecessary confusion in the mind of the
public regarding the forms of lime that should be used. If amounts
greatly in excess of needs were being applied, the form would be a
matter of concern. There would arise the question of soil injury that
might result from the use of the lime in caustic form. Again, if
pulverized limestone were used, a very heavy application would bring up
the question of coarseness in order that waste by leaching might be
escaped. Most farms needing lime do not have cheap supplies, and the
consideration is to secure soil alkalinity at a cost that will not be
excessive. Freight rates and the cost of hauling to the fields, added
to first cost of the lime, limit applications on most farms to the
necessities of a single crop-rotation which includes clover, or, at the
most, to two crop-rotations. Under these circumstances it is best to
let cost of correction of soil acidity determine the form of lime to be
used.
The material that will render the soil friendly to clover for the least
money is the right one to select. We need to be concerned only with the
relative efficiencies of the various forms of lime, as measured in
terms of money. That which will most cheaply restore heavy clover
growths to the land is the form of lime to be desired. The contentions
of salesmen may well be disregarded as they produce confusion and delay
a work that is important to the farmer.
Definitions.--The use of the various forms of lime will become general,
and the terms employed to designate them should be understood. They
vary in their content of acid-correcting material, and their correct
names should be used with accuracy.
_Stone-lime_, often called lump-lime or unslaked lime, or calcium oxide
or CaO, is a form widely known, and may be taken as a standard. It is
the ordinary lime of commerce, and is obtained by the burning of
limestone. One hundred pounds of pure limestone will produce 56 pounds
of stone-lime (CaO).
_Pulverized lime_, often called ground lime, is stone-lime after being
pulverized to permit even distribution. When it is fully exposed to the
air or moisture, it slakes and doubles in volume.
_Hydrated lime_, often called slaked lime, is a combination of
stone-lime and water. The water causes an increase in weight of 32 per
cent, 56 pounds of stone-lime becoming 74 pounds of the hydrate.
_Pulverized limestone_, often called carbonate of lime, is the unburned
limestone made fine so that good distribution may be possible.
_Air-slaked lime_, often called carbonate of lime, is stone-lime or
hydrated lime combined with carbonic acid from the air, and thereby
increased in weight. Fifty-six pounds of stone-lime, or 74 pounds of
hydrated lime, become 100 pounds of air-slaked lime.
_Agricultural lime_, or land-lime, may embrace anything that the
manufacturer of lime chooses to market. It may be reasonably pure
unslaked lime, or it may have less value than a finely pulverized pure
limestone. There is a custom of grinding the core, or partially burned
limestone of the kiln, together with impurities removed from builders'
lime, and with this may be put some air-slaked lime. Some manufacturers
market under this name a lime of excellent value. There is no standard,
and one should not pay more than a finely pulverized pure limestone
would cost unless he knows that the content of fresh burned lime is
high.
The element with which we are concerned in any of these forms of lime
is calcium. It is the base whose union with the acids destroys the
latter. It should be obvious that the addition of water to stone-lime,
which adds weight and causes 56 pounds of the stone-lime to become 74
pounds of hydrated lime, adds no calcium. Likewise the change to the
air-slaked condition adds no calcium, but again adds weight.
The Kind to Apply.--If a soil contains free acid, the amount of calcium
needed is definite. The form of lime that can supply the need in that
particular field at least expenditure of money and trouble is the one
to be selected. A ton of stone-lime, or pulverized lime, can correct as
much acid as 2640 pounds of hydrated lime or 3570 pounds of pulverized
limestone, if all the original material was pure.
In other words, if the value of a given weight of pulverized limestone
is placed at 100, the value of the same weight of hydrated lime would
be 132 and the value of stone-lime would be 180, when each was finely
divided and distributed throughout the surface soil.
The Fineness of Limestone.--Experiments at the Pennsylvania experiment
station have shown that limestone has practically immediate
availability in an acid soil if all of it has ability to pass through a
screen having 60 meshes to the linear inch. Much of the limestone
meeting this test doubtless is fine enough to pass through an 100-mesh
screen. The requirement that a 60-mesh screen be used in testing is a
satisfactory one to the buyer that wants immediate results in the
field. A coarser product must be used in larger amount per acre, as
only the fine particles are available at once, and the object of the
application is to correct all the acidity. Where a coarse product,
containing some fine particles, can be used at such a low price per ton
that the application may consist of a large number of tons per acre,
the practice may be commended, but the essential thing is immediate
results, and only finely divided limestone can give them. Any long
railway or wagon haul makes a heavy application of coarsely pulverized
limestone inexpedient.
Hydrated Lime.--Many salesmen are too enthusiastic in their claims for
hydrated lime. It has advantages over pulverized limestone, stone-lime,
and pulverized lime, and there are disadvantages. The buyer of
pulverized limestone pays for the haul on 100 pounds of material to get
the 56 pounds of lime carried, while 74 pounds of the hydrate furnish
the same amount of actual lime, if all of it is a hydrate. While the
hydrate contains less strength than the stone-lime, it is in good
physical condition for distribution, and the stone-lime must be slaked.
The buyer will bear in mind, moreover, that much of the stone-lime
which is burned on farms comes from limestone that is not very pure,
and all impurity is waste. Most manufacturers of the hydrate locate
their costly plants where the limestone is relatively pure. Prudent
business reasons dictate such a course. A careful manufacturer of
hydrated lime takes out imperfectly burned and other faulty material
with screens. These advantages have some weight, but the fact remains
that a ton of pure stone-lime has considerably more acid-correcting
power than a ton of the hydrate.
Stone-lime.--Stone or lump-lime is composed of the 56 per cent of a
pure limestone that gives value to the limestone. Forty-four pounds of
waste material were driven off in the burning. Where railway or wagon
hauls are costly, the purchase of stone-lime is indicated. There is
advantage in getting this lime in pulverized form, provided it can be
distributed in the soil before moisture from the air induces slaking
and consequent bursting of the packages. The necessity of rapid
handling has limited the popularity of pulverized unslaked lime, but no
other form is equal to it when it is wholly unslaked. Some
manufacturers grind the partially burned limestone often found in
kilns, and furnish goods little better than pulverized limestone.
The slaking of stone-lime should be done in a large pile, and the
distribution may be made with lime-spreaders. When the application is
fairly heavy, a manure-spreader does satisfactory work. A good
lime-spreader is to be desired, but care must be used to remove any
stones or similar impurities in the slaked lime when filling it. Such
spreaders are on the market.
The practice of slaking lime in small piles in the field is wasteful.
It is difficult to reduce all the lime to a fine powder and to make
even distribution over the surface. Any excess of water from rains
puddles some of the lime, destroying practically all its immediate
effectiveness. Distribution with shovels is necessarily imperfect.
The labor of slaking stone-lime and the difficulty in distribution are
two factors to be considered when selecting the form of lime to be
used. They may counter-balance in some instances the higher percentage
of actual lime when comparison is made with the hydrate. That is a
question to be decided by the buyer. He must be willing to use methods
that will secure even distribution. The prevailing practice, however,
of marketing the hydrate at a much higher price per ton than the
stone-lime should prevent sales to farmers. The price paid for ease of
handling is too great when purchase of the hydrate is made under such
circumstances. It is better to do the slaking at home, furnishing the
added weight of 32 per cent in water on the farm.
Ashes.--Hard-wood ashes have ceased to have much importance as a source
of lime for land, but their use is held in high esteem even by those
who regard fertilizers as mere stimulants and doubt the efficiency of
lime. Hard-wood ashes, unleached, clean and dry, are valuable for acid
soils. Their content of potash, which is variable and averages about 4
per cent, formerly was given all the credit for the soil improvement
and increased clover growth that resulted from their use. Tests with
other carriers of potash have shown that the potash probably produced
only a small part of the effect noted, and the benefit is attributable
to the lime in the ashes which exists in an effective form. The content
of lime is variable, and largely so on account of the percentage of
moisture and dirt that may be found in most ashes, and when no analysis
has been made, the estimate of value should not be based on more than
30 to 40 per cent of carbonate of lime. The price of ashes runs so
high, as a result of prejudice in favor of this well-known kind of soil
amendment, that it rarely is advisable to buy them. Pure lime is a
cheaper means of correcting the soil acidity, and the sulphate or the
muriate of potash is by far the cheaper source of potash.
Marl.--Marls vary widely in composition. When quite pure, they contain
90 or more per cent of carbonate of lime, and have a value per ton
about equal to finely pulverized limestone, and near half the value per
ton of stone-lime. There are marls that are carriers of potash and
phosphoric acid, and are to be valued accordingly as fertilizers.
Magnesian Lime.--Some limestone is a nearly pure calcium compound, and
yields a pure lime, while much limestone contains a high percentage of
magnesia. The latter is preferred by manufacturers who furnish
pulverized lime because it does not slake readily, and is less liable
to burst the packages before required for use. A pound of magnesian
lime will correct a little more acid than a pound of pure lime, and no
preference may be shown the latter on that score. There are soils in
which the proportion of magnesia to pure lime is too great for best
results with some plants, as plant biologists assure us, but there is
too little definite information respecting these soils to justify one
in paying more for a high calcium lime than for a magnesian lime when
it is to be used on acid land. The day may come when more will be
known, but the rational selection to-day is the material that will do
the required work in the soil for the least money.
Amount per Acre.--The amount of lime that should be applied to an acre
of land depends upon the degree of its acidity, the nature of the soil,
the cheapness of the lime, and the character of the crops to be grown.
The actual requirement for the moment could be determined by a chemical
test, but the application should carry to the soil an amount in excess
of immediate requirement. When clover has ceased to grow within recent
years, it is a fair inference that the deficiency, if it exists, has
not become great. When sorrel and plantain have gained a strong
foothold, indicating that good grasses are unable to replace clover,
the degree of acidity probably is higher. The results of tests at
experiment stations and on farms show that 1000 pounds of pulverized
lime, or one ton of pulverized limestone, evenly distributed throughout
the surface soil, can restore clover to the crop-rotation on much land.
This is an application so light that a state of alkalinity cannot be
long retained. It is better to apply the equivalent of a ton of
stone-lime in the case of all heavy soils that have shown any acidity.
Where lime is low in price, 3000 pounds of stone-lime, or its
equivalent in any other form of lime, is advised, the belief being that
such an application will maintain good soil conditions through two
crop-rotations, or eight to ten years. This amount can be applied quite
successfully with a manure-spreader, and meets the convenience of the
man who burns his own lime and does not want to screen it for use in a
lime-spreader. The man who must buy his lime, and pay a freight charge
upon it, will find it better to use only a ton per acre. This advice
applies to heavy soils. A light, sandy soil should be given only a
small application, as otherwise physical condition may be injured. The
lime, used in excess, has an undue binding effect upon the sand. An
application of 1000 pounds of stone-lime per acre can be made with
safety.
Time of Application.--The use of lime on land should be associated in
the land-owner's thoughts with the growing of clover. It does help soil
conditions so that more grain can be produced, but if it is permitted
to displace the use of fertilizers, and does not lead to the growth of
organic matter, harm will result in the end. Lime should be applied to
secure clover, and therefore it should be mixed with the soil before
the clover is sown. The application may be made when fitting the
seed-bed for the grain with which clover usually is seeded, or may be
given a year or two years previous to that time. The important point is
to have the soil friendly to plant life when a sod is to be made.
Lime should be put on ground always after the plowing, and it should be
well mixed with the surface soil. Even distribution is just as
important in its case as in that of fertilizers. A good practice is to
break a sod for corn, harrowing and rolling once, and then to put on
the lime. A cut-away or disk harrow should be used to mix the lime with
the soil before any moisture causes it to cake. When large crumbs form,
immediate efficiency is lost.
If the application is light, and may barely be equal to immediate
demand, it is better practice to put on the lime when preparing the
seed-bed for the wheat or other small grain in which the clover will be
sown. It should never be mixed with the fertilizer nor applied with the
seed. The lime should go into the soil a few days, or more, prior to
the seeding. The soil having been put into a condition favorable to
plant life, the seeding and the use of commercial fertilizers should
proceed as usual.
Lime should never be mixed with manure in the open air, but it is good
practice to plow manure down, and then to use lime as indicated above,
if needed. If manure and lime must be used after the land has been
plowed, the lime should be disked well into the soil before the manure
is applied, and it is advisable that the interval between the two
applications be made as long as possible.
CHAPTER IV
ORGANIC MATTER
Office of Organic Matter.--The restoration of an impoverished soil to a
productive state usually is a simple matter so far as method is
concerned. It may be a difficult problem for the individual owner on
account of expense or time involved, but he has only a few factors in
his problem. Assuming that there is good drainage, and that the lime
requirement has been met, the most important consideration is organic
matter. A profitable agriculture is dependent upon a high percentage of
humus in the soil. Average yields of crops are low in this country
chiefly because the humus-content has been greatly reduced by bad
farming methods.
[Illustration: Turning down organic matter with a gang plow.]
Nature uses organic matter in the following ways:
1. To give good physical condition to the soil. The practical
farmer appreciates the importance of this quality in a soil. Clayey
soils are composed of fine particles that adhere to each other.
They are compact, excluding air and failing to absorb the water
that should be held in them. The excess of water finally is lost
by evaporation, and the sticky mass becomes dry and hard. The
incorporation of organic matter with clay or silt changes the
character of such land, breaking up the mass, and giving it the
porous condition so essential to productiveness. Improved physical
condition is likewise given to a sandy soil, the humus binding the
particles together.
2. To make the soil retentive of moisture. Yields of crops are
limited more by lack of a constant and adequate supply of moisture
throughout the growing season than by any other one factor. Decayed
organic matter has great capacity for holding moisture, and in some
measure should supply the water needed during periods of light
rainfall.
3. To serve, directly and indirectly, as a solvent of the inert
plant-food in the soil that is known as the "natural strength" of
the land. Its acids do this work directly, and by its presence it
makes possible the work of the friendly bacteria that are man's
chief allies in maintaining soil fertility.
4. To furnish plant-food directly to growing plants. Even when it
has been produced from the soil supplies alone, there is great gain
because the growing crop must have immediately available supplies.
Many of the plants used in providing humus for the soil are better
foragers for fertility than other plants that follow, sending their
roots deeper into the subsoil or using more inert forms of
fertility.
The Legumes.--Any plant that grows and rots in the soil adds to the
productive power of the land if lime is present, but plants differ in
value as makers of humus. There are only ten essential constituents of
plant-food, and the soil contains only four that concern us because the
others are always present in abundance. If lime has been applied to
give to the soil a condition friendly to plant life, we are concerned
with three constituents only, viz. nitrogen, phosphoric acid, and
potash. The last two are minerals and cannot come from the air. They
must be drawn from original stores in the soil or be obtained from
outside sources in the form of fertilizers. The nitrogen is in the air
in abundance, but plants cannot draw directly from this store in any
appreciable amount. The soil supply is usually light because nitrogen
is unstable in character and has escaped from all agricultural land in
vast amounts during past ages.
Profitable farming is based upon the great fact that we have one class
of plants which can use bacteria to work over the nitrogen of the air
into a form available for their use, and the store of nitrogen thus
gained can be added to the soil's supply for future crops. These
plants, known as legumes, embrace the clovers, alfalfa, the vetches,
peas, beans, and many others of less value. They provide not only the
organic matter so much needed by all thin soils, but at the same time
they are the means of adding to the soil large amounts of the one
element of plant-food that is most costly, most unstable, and most
deficient in poor soils. Their ability to secure nitrogen for their own
growth in poor land also is a prime consideration in their selection
for soil improvement, assuring a supply of organic matter where
otherwise partial failure would occur.
Storing Nitrogen.--Man needs protection from his own greed, and
nature's checks are his salvation. An illustration is afforded in the
case of legumes grown for the maintenance of soil fertility. The
clovers and some other legumes are seeded primarily for the benefit of
the soil. The need of organic matter is recognized, and a cheap supply
of nitrogen is wanted for other crops in the rotation. The purpose of
the seeding is praiseworthy, but if all of the product were available
for use off the land, observation teaches that the soil producing the
crop probably would fare badly. The crops grown prior to the season
devoted to legumes proclaim their need of better soil conditions, more
organic matter, and more nitrogen, but the legumes, appropriating
nitrogen for themselves, give to the land a more prosperous appearance,
and the disposition to harvest everything that is in sight prevails.
There is the excusing intention to return to the soil the residue from
feeding, which should be nearly as valuable as the original material,
while the fact usually is that faulty handling of the manure results in
heavy loss, and the distribution of the remainder is imperfect. There
is no happier provision of nature for the guarding of the soil's
interests than the unavailability for man's direct use of a
considerable part of most plants, thus saving to the land a portion of
its share of its products. The humus obtained from plant-roots,
stubble, and fallen leaves forms a large percentage of all the humus
obtained by land whose fertility is not well guarded by owners. This
proportion is large in some legumes, amounting to 30 or 40 per cent in
the case of red and mammoth clover.
The Right Bacteria.--The word "bacteria" has had a grudging admission
to the vocabulary of practical farmers, and the reason is easily
stated. The knowledge of bacteria and their work is recent and limited.
They are many in kind, and scientists are only in the midst of their
discoveries. The practical farmer does well to let bacteriologists
monopolize interest in the whole subject except in so far as he can
provide some conditions that have been demonstrated to be profitable.
The work of bacteria must come more and more into consideration by the
farmer because nature uses them to produce a vast amount of the change
that is going on around us.
In consideration of the value of legumes we must take into account the
bacteria which they have associated with them, and through which they
obtain the atmospheric nitrogen. This would be a negligible matter, it
may be, if all legumes made use of the same kind of bacteria. It is
true that the bacteria must have favorable soil conditions, but they
are the same favorable conditions that our plants require. A fact of
importance to the farmer is that the bacteria which thrive on the roots
of some legumes will not serve other legumes. This is a reason for many
failures of alfalfa, crimson clover, the soybean, the cowpea, hairy
vetch, and other legumes new to the region.
Soil Inoculation.--The belief that the right kind of bacteria may be
absent from the soil when a new legume is seeded, and that they should
be supplied directly to the soil, has failed in ready acceptance
because examples of success without such inoculation are not uncommon.
Even if the explanation of such success is not easy, the fact remains
that legumes new to a region usually fail to find and develop a supply
of bacteria adequate for a full yield, and some of these legumes, of
which alfalfa is an example, make a nearly total failure when seeded
for the first time without soil inoculation. Experiment stations and
thousands of practical farmers have learned by field tests that the
difference between success and failure under otherwise similar
conditions often has been due to the introduction of the right bacteria
into the soil before the seeding was made.
Explanations offered for any phenomenon may later become embarrassing
in the light of new knowledge. We do not really need to know why an
occasional soil is supplied with the bacteria of a legume new to it. We
have learned that the bacteria of sweet clover serve alfalfa, and this
accounts for the inoculation of some regions in the east. We believe
that some bacteria are carried in the dust on the seed, and produce
partial inoculation. Other causes are more obscure. The cowpea trails
on the ground, and carries its bacteria more successfully than the
soybean. Most legumes require a soil artificially inoculated when
brought into a new region, failing otherwise in some degree to make
full growth.
Method of Inoculation.--The bacteria can be transferred to a new field
by spreading soil taken from a field that has been growing the legume
successfully. The surface soil is removed to a depth of three inches,
and the next layer of soil is taken, as it contains the highest
percentage of bacteria. They develop in the nodules found on the
feeding roots of the plants. The soil is pulverized and applied at the
rate of 200 pounds per acre broadcast. If the inoculated soil is near
at hand and inexpensive, 500 pounds should be used in order that the
chance of quick inoculation may be increased. The soil should be spread
when the sun's rays are not hot, and covered at once with a harrow, as
drying injures vitality. The soil may be broadcasted by hand or applied
with a fertilizer distributer. The work may be done at any time while
preparing the seed-bed. The bacteria will quickly begin to develop on
the roots of the young plants, and nodules may be seen in some
instances before the plants are four weeks old.
Pure cultures may be used for inoculation. Some commercial concerns
made failures and brought the use of pure cultures into disrepute a few
years ago, but methods now are more nearly perfect, and it is possible
to buy the cultures of all the legumes and to use them with success.
Prices continue too high to make the pure cultures attractive to those
who can obtain inoculated soil with ease. If land has been producing
vigorous plants, and if it contains no weeds or disease new to the land
to be seeded, its soil offers the most desirable means of transferring
the bacteria.
The claim is made by some producers of pure cultures that their
bacteria are selected for virility, and should be used to displace
those found in the farmer's fields. The chances are that, if soil
conditions are good, the bacteria present in the soil are virile, and
if the conditions are bad, the pure cultures will not thrive. All
eastern land is supplied with red clover bacteria, just as some western
land possesses alfalfa bacteria, and partial clover failure has causes
wholly apart from the character of its bacteria.
We do not have definite knowledge concerning duration of inoculation
nor the manner in which it is maintained when legumes are not growing,
but we do know that when a legume has once made vigorous growth in a
field, the soil will remain inoculated for a long term of years.
CHAPTER V
THE CLOVERS
Red Clover.--Wherever red clover thrives there is no more valuable
plant than this legume for making and keeping soils productive under
ordinary crop-rotations. The tyro in farming finds his neighbors
conservative in thought and method, and may rightly see room for
improvement. He naturally turns to new crops that are receiving much
exploitation, but should bear in mind that the world nowhere has found
a superior to red clover as a combined fertilizing and forage crop for
use in short rotations. Farmers turn aside from it because it turns
aside from them. There has been increasing clover failure in our older
states for a long term of years. It has become the rule to seed to
timothy with the clover in the short crop-rotations as well as in the
longer ones, and chiefly for the reason that clover seeding has become
no longer dependable. In many regions the proportion of timothy seed
used per acre has been made large because the clover would not surely
grow. In the winter-wheat belt, where the custom has been to make such
seedings with wheat, timothy being sown in the fall and clover the next
spring, this increase in the timothy has made matters worse for the
clover, but it has helped to insure a sod and a hay crop. "Clover
sickness," supposedly resulting from close clover rotations, and the
prevalence of plantain and other weeds, have been assigned as a partial
cause of clover failure. It is only within recent years that the true
cause of much failure has been recognized.
Clover and Acid Soils.--There are limited areas in which some clover
disease has flourished, and in some years insect attacks are serious.
Barring these factors which have relatively small importance when the
entire clover area is taken into account, the causes of clover failure
are under the farmer's control. The need of drainage increases, and the
deficiency in organic matter becomes more marked. The sale of hay and
straw, and especially the loss of liquid manures in stables, have
robbed many farms. These are adverse influences upon clover seedings,
but the most important handicap to clover is soil acidity. There is sad
waste when high-priced clover seed is put into land so sour that clover
bacteria cannot thrive, and there is ten-fold more waste in letting
land fail to obtain the organic matter and nitrogen clover should
supply. When land-owners refuse to let their soils remain deficient in
lime, clover will come into a prominence in our agriculture that it
never previously has known.
Methods of Seeding.--It is a common practice to sow clover in the
spring, either with spring grain or with wheat or rye previously seeded
in the fall. This method has much to commend it. The cost of making the
seed-bed is transferred to the grain crop, and there is little outlay
other than the cost of seed. Wheat and rye offer better chances to the
young clover plants than do the oat crop which shades the soil densely
and ripens later in the summer. The amount of seed that should be used
depends upon the soil, the length of time the sod will stand, and the
purpose in growing the clover. When soil fertility is the one
consideration, 12 to 15 pounds of bright, plump medium red clover seed
per acre should be sown. A fuller discussion of the principles involved
in making a sod and of seed mixtures is given in Chapters VII and VIII.
Fertility Value.--Attempts have been made to express the actual value
of a good clover crop to the soil in terms of money. The number of
pounds of matter in the roots and stubble has been determined, and
analyses show the percentage of nitrogen, phosphoric acid, and potash
contained. The two crops harvested in the second year of its growth
likewise have their content of plant-food determined. If the total
amounts of nitrogen, phosphoric acid, and potash have their values
fixed by multiplying the number of pounds of each ingredient of
plant-food by their respective market values, as is the practice in the
case of commercial fertilizers, a total valuation may be placed upon
the clover, roots and top, as a fertilizer. Such valuation is so
misleading that it affords no true guidance to the farmer. In the first
place, the phosphoric acid and potash were taken out of the soil, and
while some part of these materials may have been without immediate
value to another crop until used by the clover, no one knows how much
value was given to them by the action of the clover. Again, no one
knows what percentage of the nitrogen in the clover came from the air,
and how much was drawn from the soil's stores. The proportion varies
with the fertility of the land, the percentage of nitrogen taken from
the air being greater in the case of badly depleted soils.
A big factor of error is found in the valuations of the ingredients
found in the crop. All plant-food is worth to the farmer only what he
can get out of it. He may be able to use 50 pounds of nitrogen per acre
in the form of nitrate of soda, at 18 cents a pound, when growing a
certain crop, but could not afford to buy, at market price of organic
nitrogen, all the nitrogen found in the clover crop, and therefore it
does not have that value to him.
On the other hand, these estimates do not embrace the great benefit to
the physical condition of the soil that results from the incorporation
of a large amount of vegetable matter.
Discussion has been given to this phase of the question in the interest
of accuracy. Values are only relative. The practical farmer can
determine the estimate he should put upon clover only by noting its
effect upon yields in the crop-rotation upon his own farm. It is our
best means of getting nitrogen from the air, it provides a large amount
of organic matter, it feeds in subsoil as well as in top soil, bringing
up fertility and filling all the soil with roots that affect physical
condition favorably, and it provides a feed for livestock that gives a
rich manure.
[Illustration: Red clover on the farm of P. S. Lewis and Sons, Point
Pleasant, W. Va.]
Taking the Crops off the Land.--The feeding value of clover hay is so
great that the livestock farmer cannot afford to leave a crop of clover
on the ground as a fertilizer. The second crop of red clover produces
the seed, and, if the yield is good, is very profitable at the prices
for seed prevailing within recent years. The amount of plant-food taken
off in the hay and seed crops would have relatively small importance if
manure and haulm were returned without unnecessary waste. Van Slyke
states that about one third of the entire plant-food value is contained
in the roots, while 35 to 40 per cent of the nitrogen is found in the
roots and stubble. Hall instances one experiment at Rothamstead in
which the removal of 151 pounds of nitrogen in the clover hay in one
year left the soil enough richer than land by its side to produce 50
per cent more grain the next year. He cites another experiment in which
the removal of three tons of clover hay left the soil so well supplied
with nitrogen that its crop of Swede turnips two years later was over
one third better than that of land which had not grown clover, the
application of phosphoric acid and potash being the same. When two tons
of well-cured clover hay are harvested in June, removing about 80
pounds of nitrogen, 45 to 50 pounds are left for the soil. The amounts
of potash are about the same, while phosphoric acid is much less in
amount.
Physical Benefit of the Roots.--While the roots and stubble contain
less than two fifths of the total plant-food in a clover crop, one may
not safely infer that the removal of the crop for hay reduces the
beneficial effect of the clover to the soil fully 60 per cent, or more.
The roots break up the soil in a way not possible to a mass of tops
plowed down. They improve the physical condition of the subsoil as well
as the top soil. The amount of the benefit depends in part upon the
nature of the land. Its value cannot be surely determined, but the
facts are called to mind as an aid to judgment in deciding upon the
method of handling the clover crop.
Used as a Green Manure.--Where dependence must be placed upon clover as
a fertilizer, little or no manure being returned to the land, at least
one of the two clover crops within the year should be left on the land.
The maximum benefit from clover, when left on the land, can be obtained
by clipping it before it is sufficiently heavy to smother the plants,
leaving it as a mulch. When the cutter-bar of the mower is tilted
upward, the danger of smothering is reduced. Truckers, remote from
supplies of manure, have found it profitable to make two such clippings
just prior to blossoming stage, securing a third heavy growth. The
amount of humus thus obtained is large, and the benefit of the mulch is
an important item.
Some growers clip the first crop for a mulch, and later secure a seed
crop. The early clipping and the mulch cause increase in yield of seed.
A common practice is to take one crop off for hay, and to leave the
second for plowing down the following spring. Early harvesting of the
clover for hay favors the second crop.
When to turn Down.--When the maximum benefit is desired for the soil
from a crop of clover, the first growth should not be plowed down. Its
office should be that of a mulch. In its decay all the mineral
plant-food and most of the nitrogen go into the soil. The second crop
should come to maturity, or near it. As a rule, there is gain, and not
loss, by letting the second crop lie on the ground until spring if a
spring-planted crop is to follow. Some fall growth, and the protection
from leaching, should equal any advantage arising from rotting the
bulky growth in the soil. In some regions it is not good practice to
plow down a heavy green crop on account of the excessive amount of acid
produced. When this has been done, the only corrective is a liberal
application of lime.
Mammoth Clover.--When clover is grown with timothy for hay, some
farmers prefer to use mammoth clover in place of the medium red. It may
be known as sapling clover, and is accounted a perennial, though it is
little more so than the red. It is a strong grower and makes a coarse
stalk but, when grown with timothy, it has the advantage over the red
in that the period of ripening is more nearly that of the timothy. It
inclines to lodge badly, and should be seeded thinly with timothy when
wanted for hay. The roots run deep into the soil, and this variety of
clover compares favorably with the medium red in point of fertilizing
power, the total root-growth being heavier. While its yield of hay,
when seeded alone, is greater than the first crop of the red, its
inclination to lodge and its coarseness are offsets. It produces its
seed in the first crop, and the after-growth is small, while red clover
may make a heavy second crop. Its use should become more general on
thin soils, its strong root-growth enabling it to thrive better than
the red, and the lack of fertility preventing the stalks from becoming
unduly coarse for hay. The amount of seed used per acre, when grown by
itself, should be the same as that of red clover.
Alsike Clover.--A variety of clover that may have gained more
popularity than its merit warrants is alsike clover. It is more nearly
perennial than the mammoth. The roots do not go deep into the subsoil
like those of the red or the mammoth, and therefore it is better
adapted to wet land. It remains several years in the ground when
grazed, and is usually found in seed mixtures for pastures. It is
decumbent, and difficult to harvest for hay when seeded alone. It is
credited with higher yields than the red by most authorities, but this
is not in accord with observation in some regions, and it is markedly
inferior to the red in the organic matter and the nitrogen supplied the
soil in the roots.
The popularity of this clover is due to its ability to withstand some
soil acidity and bad physical conditions. In regions where red clover
is declining on account of lack of lime, one may see some alsike. The
rule is to mix alsike with the red at the rate of one or two bushels of
the former to six bushels of the latter. As the seed of the alsike is
hardly half as large as that of the red, the proportion in the mixture
is greater than some farmers realize. The practice is an excellent one
where the red will not grow, and the alsike adds fertility, but when
the soil has been made alkaline, the red clover should have nearly all
the room. Alsike is a heavy producer of seed.
Crimson Clover.--Wherever crimson clover is sufficiently hardy to
withstand the winter, as in Delaware and New Jersey, it is a valuable
aid in maintaining and increasing soil fertility. It is a winter
annual, like winter wheat, and should be seeded in the latter half of
summer, according to latitude. It comes into bloom in late spring. The
plant has a tap-root of good length, but in total weight of roots is
much inferior to the red. This clover, however, compares favorably with
red clover in the total amount of nitrogen added to the soil by the
entire plant when grown under favorable conditions. It is peculiarly
fitted for a cover crop in orchards and wherever spring crops are
removed as early as August, or a seeding can be made in them, as is the
case with corn. Even when winter kills the plants, a successful fall
growth is highly profitable, adding more nitrogen before winter than
red clover seeded at the same time. Where the plants do not
winter-kill, they are plowed down for green manure when in bloom in
May, or earlier in the spring to save soil moisture and permit early
planting, although a good hay for livestock can be made, and the yield
is about the same as that of the first crop of red clover.
In the northern states a large amount of money has been wasted in
experimental seedings with crimson clover, and it is only in
exceptional cases that it continues to be grown. There is reason to
believe that many of these failures were due to lack of soil
inoculation. The Pennsylvania experiment station is located in a
mountain valley where winters are severe. Crimson clover is under test
with other cover crops for an experimental orchard, and success with it
has increased as the soil has become fully inoculated. This view is
supported by the experience of various growers in the North, and while
crimson clover can never make the success in a cold climate that it
does in Delaware, there is a much wider field of usefulness for it than
is now occupied. Experiments should be made with it under favorable
conditions respecting moisture and soil tilth. Fifteen pounds of seed
should be used, and the seed should be well covered, as is the case
with all seeds sown in mid-summer.
CHAPTER VI
ALFALFA
Adaptation to Eastern Needs.--The introduction of alfalfa into the
eastern half of the United States will prove a boon to its depleted
soils, encouraging the feeding of livestock and adding to the value of
manures. It will affect soils directly, as does red clover, when
farmers appreciate the fact that its rightful place on their farms is
in rotation with grain. Under western conditions, where no other crop
can compete with it in value, as is the case in semi-arid belts, its
ability to produce crops for a long term of years adds much to its
value, but in eastern agriculture this characteristic is not needed. On
most soils of the east it will not remain productive for more than four
to six years, and that fact detracts little from its value. It should
fit into crop-rotations, adding fertility for grain crops. When grown
in a six-years rotation with corn and oats or other small grain, it
furnishes a rich sod for the corn, and the manure made from the hay
helps to solve the farmer's fertility problem.
Fertility and Feeding Value.--Vivian says that "the problem of the
profitable maintenance of fertility is largely a question of an
economic method of supplying plants with nitrogen." The greatest value
of alfalfa to eastern farming lies in its ability to convert
atmospheric nitrogen into organic nitrogen. It has no equal in this
respect for relatively long crop-rotations, storing in its roots and
successive growths of top far more nitrogen within three or four years
than is possible to any other of our legumes. A good stand of alfalfa,
producing nine crops of hay in the three years following the season of
seeding, will produce from nine to twelve tons of hay. Good fields,
under the best conditions, have produced far more, but the amounts
named are within reach of most growers on land adapted to the plant. A
ton of hay, on the average, contains as much nitrogen as five or six
tons of fresh stable manure. Thus there comes to the farm a great
amount of plant-food, to be given the land in the manure, and in
addition the roots and stubble have stored in the ground enough
nitrogen to feed a successive corn crop, and a small grain crop which
may follow the corn. Moreover, the roots have filled the soil with
organic matter, improving the physical condition of the soil and
subsoil.
[Illustration: Alfalfa on the Ohio State University Farm.]
Another gain is found in the content of phosphoric acid and potash in
the manure, much of which was drawn from soil supplies out of reach of
the other farm crops. The profit from introduction of alfalfa into a
region's agriculture is very great.
Alfalfa makes a nutritious and palatable feed for livestock. A ton
contains as much digestible protein as 1600 pounds of wheat bran.
Climate and Soil.--The experimentation with alfalfa by farmers has been
wide-spread, and the percentage of failure has been so large that many
have believed this legume was unfitted to the climate and soil of the
country east of the Missouri River. Successful experience has shown
that it can be made to take a considerable place in eastern
crop-schemes. The climate is not unfavorable, as is evidenced by large
areas of good alfalfa sods on thousands of farms. The abundant rainfall
brings various weeds and grasses into competition with it, and that
will remain a serious drawback until growers learn to clean their
surface soils by good tillage before seeding.
Any land that is sufficiently well drained to produce a good corn crop
in a wet summer can grow alfalfa if the seed-bed is rightly made. The
loose soils are more difficult to seed successfully than is the land
having enough clay to give itself body, although most experimenters
select their most porous soils. All farms having good tilth can bring
alfalfa into their crop-rotations.
Free Use of Lime.--The conditions requisite to success in
alfalfa-growing are not numerous, but none can be neglected. Alfalfa
should be given a calcareous soil when possible, but an acid soil can
be made favorable to alfalfa by the free use of lime. There must remain
a liberal amount after the soil deficiency has been met, and when the
use of lime is on a liberal scale, the pulverized limestone makes the
safest carrier. However, 50 bushels of stone-lime per acre can be used
safely on any land that is not distinctly sandy, and that amount is
adequate in most instances.
Inoculation.--The necessity of inoculation has been discussed in
Chapter IV. Eastern land would become inoculated for alfalfa if farmers
would adopt the practice of mixing a little alfalfa with red clover
whenever making seedings. Some alfalfa plants usually make growth,
securing the bacteria in the dust of the seed, presumably. The addition
of one pound of alfalfa seed per acre would assist materially in
securing a good stand when the day came that an alfalfa seeding was
desired.
Fertilization.--The ability of alfalfa to add fertility to the farm,
and directly to the field producing it when all the crops are removed
as hay, does not preclude the necessity of having the soil fertile when
the seeding is made. The plants find competition with grass and other
weeds keen under eastern skies where moisture favors plant-life. In
their first season this is markedly true. There should be plenty of
available plant-food for the young plants. Stable manure that is free
from the seeds of pernicious weeds makes an excellent dressing. It is
good practice to plow down a heavy coat of manure for corn and then to
replow the land for alfalfa the next season. A top-dressing of manure
is good, affording excellent physical condition of the surface for
starting the plants. Eight tons per acre make a good dressing.
If land is not naturally fertile, mineral fertilizers should be
applied. A mixture of 350 pounds of 14 per cent acid phosphate and 50
pounds of muriate of potash is excellent for an acre of manured land.
In the absence of manure, 100 pounds of nitrate of soda and 50 pounds
of muriate of potash should be added to the mixture. If the materials
are wet, a drier must be used. The fertilizer should be drilled into
the ground prior to the seeding.
A Clean Seed-bed.--Much failure with alfalfa is due to summer grasses
and other weeds. The moisture in our eastern states favors plant-life,
and most soils are thoroughly stocked with the seeds of a large number
of weeds. The value of blue-grass and timothy would be comparatively
small if they were not capable of monopolizing the ground when well
started and given fertility. Alfalfa plants are less capable of
crowding out other plants, and especially in their first season. Their
habit of growth is unlike that of grass. Rational treatment of alfalfa
demands that the surface soil be made fairly clean of weed seed, and
this applies with peculiar force to annual grasses, like fox-tail. If
attention were paid to this point, failures would be far less numerous.
Old grass land should not be seeded until a cultivated crop has
followed the plowing. The land should be in good tilth, and capable of
producing a good crop of any sort. Alfalfa is not a plant for poor
land, although it does add organic matter and nitrogen.
Varieties.--There is only one variety of alfalfa in common use in this
country, and the western-grown seed sold upon the market is known
simply as alfalfa. Bound up in this one so-called variety are many
strains differing in habit of growth, and their differentiation will
occur, just as it has in the case of wheat, and is now proceeding
slowly with timothy. The eastern grower at present should use the
variety of the west that is furnishing nearly all the seed produced in
this country. There is a variety known as Sand Lucerne that has shown
value for the light, sandy soils of Michigan. The Turkestan variety was
introduced for dry, cold regions, but does not produce much seed.
Clean Seed.--Care should be exercised to secure seed free from
impurities. If one is not a competent judge, he should send a sample to
his state experiment station for examination. The practice of
adulteration is decreasing, but the seed may have been taken from land
infested with pernicious weeds.
The impurity most to be feared is dodder. There are several varieties,
the seeds varying in size and color. The same pest may be found in
clover fields, but the injury is less because the clover stands only
two years. The dodder seed germinates in the soil, and the plant
attaches itself to the alfalfa, losing its connection with the soil and
forming a mass of very fine vines that reach out to other alfalfa
plants. In this way it spreads, feeding on the sap of the host plants
and killing them.
When the infestation is in only a few spots in the field, the remedy is
to cover with straw, soak with kerosene oil, and burn. All the
infestation at the edges of these spots must be destroyed.
When the dodder is too widely distributed throughout the field to
permit of this treatment, the only course is to plow the field at once,
and to grow cultivated crops for two or three years. It is believed
that no variety of dodder produces seed freely in the eastern states,
and that the hay made from the first crop of alfalfa or red clover will
not contain any seed of this pernicious plant.
The Seeding.--When alfalfa has become established on eastern farms, the
difficulties in making new seedings will be smaller. The experience of
growers will save from mistakes in selection of soils and preparation
of the ground, and the thorough inoculation with the right bacteria
that can come only with time will do much to insure success. The
unwisdom of making seedings in ground filled with grass and other weed
seeds will be appreciated. It is quite probable that much successful
seeding will be made in wheat and oats, where the alfalfa is to stand
only one or two years. These practices are not for the beginner. His
land is not thoroughly supplied with bacteria, and every chance should
be given the alfalfa.
If there are no annual grasses, such as appear so freely in some
regions in mid-summer, spring seeding is excellent. A cover crop is
then desirable, and nothing is better for this purpose than barley at
the rate of 4 pecks of seed per acre. In all experimental work 25
pounds of bright, plump alfalfa seed per acre should be sown. The
seeding should be made as soon as spring comes, the barley being
drilled in, and the seed-spouts of the drill thrown forward so that the
alfalfa will fall ahead of the hoes and be covered by them.
Seeding in August.--Much land is infested with annual grasses and other
weeds, and in such case seedings should be made in August, as described
in Chapter VIII.
Subsequent Treatment.--If the alfalfa plants find the bacteria at hand,
they will begin to profit from them within the first month of their
lives. A large percentage of the plants may fail to obtain this aid in
land which has not previously grown alfalfa, and within a few months
they indicate the failure by their light color, while the plants
liberally supplied with nitrogen through bacteria become dark green.
Where there are no bacteria, the plants turn yellow and die.
There are diseases that attack alfalfa, causing the leaves to turn
yellow, and when they appear, the only known treatment of value is to
clip the plants with a mower without delay. The next growth may not
show any mark of the diseases.
[Illustration: Curing alfalfa at the Pennsylvania Experiment Station.]
When alfalfa is seeded in the spring on rich land, a hay crop may be
taken off the same season. If the plants do not make a strong growth,
they should be clipped, and the tops should be left as a mulch. The
clipping and all future harvestings are made when the stalks start buds
from their sides near the ground. This ordinarily occurs about the time
some flowers show, and is the warning that the old top should be cut
off, no matter how small and unprofitable for harvesting it may be. The
exception to this rule is found only in the fall. An August seeding may
make such growth in a warm and late autumn that flowering will occur,
and lateral buds start, but the growth should not be clipped unless
there remains time to secure a new growth large enough to afford winter
protection. This is likewise true of a late growth in an old alfalfa
field.
Owners of soils that are not well adapted to the alfalfa plant will
find top-dressing with manure helpful to alfalfa fields when made in
the fall. The severity of winters in a moist climate is responsible for
some failures. If the soil is not porous, heaving will occur. A
dressing of manure, given late in the fall, and preferably during the
first hard freeze, will prevent alternate thawings and freezings in
some degree. The manure should have been made from feed containing no
seeds of annual grasses or other weed pests.
Rolling in the spring does not serve to settle heaved alfalfa plants.
The tap-roots are long, and when they have been lifted by action of
frost, they cannot be driven back into place.
It is believed that the permanence of an alfalfa seeding may be
increased by the use of mineral fertilizers in the early spring. In the
case of one alfalfa field of fifteen years' standing in the east, the
fertilizers were applied immediately after the first hay crop of the
year was removed. Three hundred and fifty pounds of acid phosphate and
50 pounds of muriate of potash per acre is the mixture recommended.
When old alfalfa plants do not stand thickly enough on the ground,
grasses and other weeds come in readily. They can be kept under partial
control by use of a spring-tooth harrow, the points being made narrow
so that no ridging will occur. The harrow should be used immediately
after the harvest, and will not injure the alfalfa.
It does not pay to use alfalfa for pasturage in our eastern states
because the practice shortens the life of the seeding.
Alfalfa makes a seed crop in profitable amount only in our semi-arid
regions. No attempt to produce a seed crop in the east should be made.
CHAPTER VII
GRASS SODS
Value of Sods.--The character of the sods is a faithful index of the
condition of the soil in any region adapted to grass. The value of
heavy sods to a soil cannot be overestimated. They not only give to a
farm a prosperous appearance, but our country's agriculture would be on
a much safer basis if heavy coverings of grass were more universal. We
do not hold the legumes in too high esteem, but the emphasis placed
upon their ability to appropriate nitrogen from the air has caused some
land-owners to fail in appreciation of the aid to soil fertility that
may be rendered by the grasses. One often hears the statement that they
can add nothing to the soil, and this is serious error. They add all
that may be given in the clovers, excepting nitrogen only, and that is
only one element of plant-food, important though it be. A great part of
the value of clover lies in its ability to supply organic matter to the
soil and to improve physical condition by its net-work of roots. Heavy
grass sods furnish a vast amount of organic matter which not only
supplies available plant-food to succeeding crops, but in its decay
affects the availability of some part of the stores of potential
fertility in the land.
[Illustration: A Heavy Grass Sod in New York.]
Prejudice against Timothy.--Timothy, among the grasses, is especially
in disrepute as a soil-builder, and yet its value is great. The belief
that timothy is hard on land is based upon observation of bad treatment
of this grass. There is a common custom of seeding land down to timothy
when it ceases to have sufficient available plant-food for a profitable
tilled crop, and usually this is the third year after a sod has been
broken. The seeding is made with a grain crop that needs all the
commercial fertilizer that may chance to be used. Clover may be seeded
also, and on a majority of farms it fails to thrive when sown. If
clover does grow, the succeeding crop of timothy may be heavy. If
clover does not grow, the timothy is not so heavy. The seeding to grass
is made partly because a tilled crop would not pay, and partly because
a hay crop is needed. It comes in where other crops cannot come with
profit, and it produces fairly well, or very well, the first year it
occupies the ground by itself. With little or no aid from manure or
commercial fertilizer, it adds much to the supply of organic matter in
the soil, and it produces a hay crop that may be made into manure or
converted into cash.
If the sod were broken the following spring, giving to the soil all the
after-math and the mass of roots, its reputation with us would be far
better than it is. This would be true even if it had received little
fertilizer when seeded or during its existence as a sod, not taking
into account any manure spread upon it during the winter previous to
its breaking for corn. But the rule is not to break a grass sod when it
is fairly heavy. The years of mowing are arranged in the crop-rotation
to provide for as many harvests as promise immediate profit. On some
land this is two years, and not infrequently it is three. Where farms
are difficult of tillage, it is a common practice to let timothy stand
until the sod is so thin that the yield of hay is hardly worth the cost
of harvesting. Then the thin remnant of sod is broken for corn or other
grain, and the poor physical condition of the soil and the low state of
available fertility lead to the assertion that timothy is hard on the
soil. This is a fair statement of the treatment of this plant on most
farms.
Object of Sods.--The land's share of its products cannot be disregarded
without loss. The legumes and grasses come into the crop-rotation
primarily to raise the percentage of organic matter that the land may
appropriate to itself within the rotation. Some of the crops usually
are for sale from the farm. Most of the crops require tillage, and that
is exhaustive of the store of humus. A portion of the time within the
rotation belongs to a crop that increases the supply of vegetable
matter, unless manure is brought from an outside source. Sods lend
themselves well to this purpose because they afford some income, in
pasturage or hay, while filling the soil with vegetation. The tendency
is to forget the primary purpose of sods in the scheme, and to ignore
the requirement of land respecting a due share of what it produces.
Attention centers upon the product that may be removed. The portion of
the farm reduced in productive power for the moment goes to grass,
while the labor and fertilizers are concentrated upon the fields that
are broken for grain and vegetables. The removal of all the crop at
harvest, and probably the pasturing of after-math, are the only matters
of interest that the fields, depleted by cultivation and seeded down to
grass, have for the owner until the poor hay yield and the need of a
sod for corn draw attention again to them.
Seeding with Small Grain.--The usual custom is to sow grasses with
small grain, and there is much to commend it. The cost of preparing the
seed-bed rests upon the grain crop, and the conditions are favorable to
fall growth and winter protection, if the seeding is made in the fall.
Wheat and rye are good crops with which to seed. In the case of fertile
land there is the danger that the timothy will establish itself too
well in a warm, moist autumn to permit clover to get a foothold the
following spring, and clover should always be seeded for the sake of
fertility. In northern latitudes clover cannot be seeded successfully
as late in the season as wheat should be sown, as it fails to become
well rooted for winter. The overcrowding of clover by timothy is met in
part by reduction in amount of timothy seed sown with the wheat.
The oat crop is less satisfactory for seedings to grass and clover. The
leaves near the ground are too thick, shading the young plants unduly,
and the late harvest exposes the grass and clover when the season is
hot, and usually dry. Some reduction in the amount of seed oats used
per acre helps to save from injury.
Seeding in Rye.--When thin land is desired for pasture, and available
fertility cannot well be applied, a sod may be formed more surely by
seeding with rye, using the rye for pasture and a mulch, than,
probably, in any other way. The ground should have good tillage and
then be seeded to rye in September at the rate of six pecks of seed per
acre. Timothy and red-top should be seeded with it, and in the spring
red and alsike clover should be added. Whenever the ground is dry
enough in the spring to permit the tramping of cattle without injury,
the rye should be pastured, and preferably by a sufficient number of
animals to hold the rye well in check. When the usual time for heading
comes, all stock should be removed, and when heads do appear, the
growth should be clipped with a mower and left as a mulch on the
surface. A second clipping will be required later, with cutter-bar
tilted well upward. When the usual summer drouth is past, livestock can
again be turned into the field. This method is suggested only for thin
fields that have failed to make catches of grass, and that for some
reason cannot well be given the fertility that all thin soils need. The
application of lime before seeding to the rye is an expense that
usually must be met in the case of such fields, and fertilizers should
be used.
Good Soil Conditions.--When the grasses and clovers desired for a sod
are sown with small grain, there is competition between them and the
grain crop for fertility, moisture, and light. The grain crop is the
one that will produce the income the following summer, and naturally is
given right of way. The amount of seed is used that experience teaches
is best for a maximum yield of grain. Usually this gives a thicker
stand of plants than is best for the tiny grass and clover plants that
often are struggling for existence down under the taller grain. If the
farmer could see his way clear to cut down the quantity of seed wheat
or oats used on a fertile soil, the catch of grass would be better, but
the small-grain crop is not very profitable at the best, and the owner
does not like deliberately to limit it.
A greater amount of failure is due to an inadequate supply of
fertility. The grass does not suffer so much from over-shading as it
does from starvation, both during the growth of the grain and after
harvest. The stronger grain plants appropriate the scanty stock of
available fertility, and leave the grass and clover nearly helpless.
This condition is especially noticeable in dry seasons when there is
less opportunity to obtain food in solution. Plants which are expected
in another season to fill the ground with vegetable matter are starved
in the beginning and die. Plant-food is needed, and should be mixed
with the soil when the seeding is made. The fertilizer needs are
discussed in another chapter.
When manure is available, it should be spread on the plowed ground and
mixed with the surface soil. If a soil is thin, or heavy, or light, the
use of a ton of manure in this way can bring greater returns than under
any other circumstances in general farming. It supplies some fertility,
and it puts the surface soil into good physical condition for young
plants. Land deficient in humus forms a crust after a rain, and a tiny
plant suffers. A light dressing of manure, well mixed with the soil,
tends to prevent this hardening of the surface and loss of water. There
is no other form of fertility that can fully replace manure, for either
compact or leachy land.
The probable need of lime has been discussed in other chapters. Clovers
and the grasses want an alkaline soil, and there is waste of money and
time in seeding acid land. The lime and the manure must not be mixed
together in the air, but both can be used when fitting land for
seeding, and both should be used if the need exists. One should be
applied early and be well disked into the soil, and then the other
application may be made and covered with the harrow. The soil is an
absorbent, and the contact of manure and lime within the soil only
leads to immediate availability, which is desirable in giving the grass
a start.
CHAPTER VIII
GRASS SODS--(_Continued_)
Seeding in Late Summer.--The natural time of beginning life, in the
case of timothy, blue-grass, red-top, red clover, and alfalfa is in the
summer or autumn. The best conditions of growth are given where no
stronger plants take the plant-food and moisture. Wherever there is any
difficulty in getting heavy grass and clover sods after the lime
deficiency has been met, and wherever a hay crop has more value than a
small-grain crop, the method of seeding alone in August should be
employed. In warmer latitudes the date may be a little later, but in
the northern states it should be in the first half of August for best
results. Seeding alone offers opportunity to make conditions right for
the seeds which are to be used, and in view of the importance of heavy
sods to our agriculture, this reason alone is sufficient. In some
regions the ability to substitute a good hay crop for a cereal that
brings small net income is an item of value, adding to the proportion
of feeding-stuff produced in the rotation and to the resulting supply
of manure. The practice of making seedings to grass and clover alone is
growing, and it is based on sound reasoning.
Crops that may Precede.--Farms that are under common crop-rotations may
adopt the practice of August seeding. The winter wheat comes off in
time for preparation, and this is true of an early variety of oats, and
of rye and barley. Early crops of vegetables get out of the way nicely.
There is a vast total area of thin soil that may be brought up to a
productive stage rapidly by the growth of a green-manuring crop to
precede the grass and clover. Rye may be sown in the fall and plowed
down in May, and cowpeas planted to be disked into the soil. Oats and
Canada peas add organic matter with nitrogen when plowed down. The
summer fallow, which deservedly has fallen into general disuse, may
well be employed when a soil is in an inert state, provided grass and
clover be permitted to appropriate the plant-food made soluble by the
fallowing. The catch crops add organic matter while cleansing the land
of weeds; the fallowing releases plant-food and is peculiarly efficient
in killing out weeds.
Care must be exercised about preserving moisture in the ground, and
therefore a green crop should not be plowed under immediately before
seeding time. When a soil is thin, there may be no better preparatory
crop than the cowpea, which will not make too rank a growth in the
north to prevent its handling with a weighted disk harrow. By this
means the soil below is left firm, and the rich vines are mixed with
the surface soil, where most needed. It is always a mistake to bury
fertility in the bottom of the furrow when a soil is thin and small
seeds are to be sown. The infertile ground lying next the subsoil is
not what is needed at the surface when preparing for a sod.
It is a good practice to use the early summer in making conditions
better for an August seeding, if the land has fallen below a profitable
state of productiveness. A growth may be plowed down in time for
firming the seed-bed, or it may be cut into the surface soil with a
harrow, or the time may be used in freeing inert plant-food and
destroying weed seed. On better soils, and in warm latitudes, a crop
for hay may be removed, especially in the case of the cowpea in the
south, and the stubble prepared for seeding by use of the cutaway or
disk harrow.
Preparation.--A seed-bed for small seeds planted in mid-summer must be
able to retain moisture. Nothing robs a soil of water more surely than
a breaking-plow. Its use is a necessity in farming, but this effect of
plowing must be borne in mind when a seeding is planned for the driest
period of the year. It goes without saying that sods should not be
formed on land that is too solid for admission of air. A thorough
plowing is needed by most soils prior to making a sod that will prevent
further stirring of the ground for a long period of time. It is best
when this plowing can be given in the preceding spring. This enables
the ground to become firm enough to hold moisture. If there is time for
a tilled crop, the cultivation is helpful. When the land must be broken
in the summer, the plowing should be done several weeks before the
seeding to grass must be made. The roller should follow the plow
closely to destroy the spaces that lie open to the hot air, permitting
the land to dry out. All deep harrowings should be given soon after the
plowing, stirring and mixing the ground, and then leaving it to settle
so that moisture can be held. It is bad practice to continue deep
harrowing until the seeding time of any small grain or grass planted in
a dry part of the year. Firmness is wanted in the soil.
The Weed Seed.--The seeds of tilled crops are planted in ground
containing much weed seed, and no harm may result. The cultivation
needed to keep the soil loose, or to prevent evaporation, destroys the
weeds. Grass, clover, alfalfa, and like seeds are put into the ground
to occupy it to the exclusion of other plants for several years, as a
rule, and no tillage can be given. The rule is to sow such seeds after
tilled crops have been grown, and some weed seed has been destroyed,
but there is evidence on every hand that the weed seed remains in
abundance. Summer preparation for grass gives opportunity to destroy a
great part of the seeds in the surface of the ground, and it is only
when they are near the surface that the seeds of most weeds will
germinate. Deep harrowings, continued up to time of planting, not only
rob land of water, but they bring to the surface new lots of seed that
had been safely buried, and become a part of the actual seeding when
the grass, clover, or alfalfa is sown. The obviously right method of
preparing for planting is to use only a surface harrow for a few weeks
previous to seeding time, stirring the ground after every rain to the
depth of three inches, or near that, and destroying the plants soon
after germination of the seed. The process which is right for holding
moisture is right for cleansing the ground.
Summer Grasses.--One of the worst pests is the annual grasses,
springing up in June, July, and August. They are responsible for many
failures to obtain stands of alfalfa, clover, and the valuable grasses.
The delay in seeding until August is due largely to this pest. When
seedings are made in the spring, or in June, failure is invited where
these grasses have a fast hold. The only effective way of combating
them is to make the ground firm enough to encourage germination, and to
stir the surface whenever a growth starts. The late seeding is the one
means of escape, and if there is fertility and moisture, the newly
seeded crop becomes well rooted by winter and takes the ground so
completely that there is little room for weeds to start the next year.
Sowing the Seed.--Partial failure with August seeding is due to faulty
methods. We are accustomed to broadcasting clover seed on top of the
wheat fields and obtaining a stand of plants. A majority of the seeds
do not become buried in the soil, or only very slightly, and yet
germinate. Moisture is necessary, but in the spring, when this method
is used, there is moisture at the surface of the ground under the wheat
plants much of the time. The conditions respecting moisture are not
unfavorable in most springs, and we come to think that a small seed
should not be buried much if any. In the autumn, again, we sow timothy
with the wheat, and while more prompt germination is secured by
covering the timothy seed with the hoes of the drill, we often have
seen a successful seeding made without any covering being given. The
work is done at a time when fall rains may continue for days and, when
the sun's heat does not continue long, the covering given by settling
the seed into the loose earth is sufficient. Moisture does not leave
rapidly because the air is not hot.
Deep Covering.--In August the air is hot, and the surface of the ground
is dry nearly all the time. A shower may be followed by hot sunshine,
and the water at the surface evaporates quickly, leaving the ground
covered with a dry crust. There are two essential things to bear in
mind: the seeding should be made only when there is enough moisture in
the ground to insure quick germination, and preferably as soon as
feasible after a rain, and the seed should be put down where moisture
can be retained. It is poor practice to sow any kind of small seeds
before a rain that seems imminent. If it forms a crust, or causes
weed-seed germination along with that of the grass seeds, only harm
results. When seeds are put into a dry soil, and a light shower comes,
there may be germination without sufficient moisture to continue life
in the plants.
The seeds should be well buried: the soil and air conditions are
different from those of the spring. It is best to wait for moisture,
and to save the seed if it does not come, but when enough water has
fallen to make the firm soil moist, the danger of failure is very small
if the seeds are buried one to two inches deep. A surface harrow will
stir the surface, and then the seeds should be sifted down into the
soil by another harrowing. A light plank float, mashing the little
clods and pressing the soil slightly together, finishes the work. The
plants will appear above ground within a few days, the only danger
being in a beating shower that may puddle the surface before the plants
are up.
Seed-mixtures.--When grass is wanted for hay as well as fertility, the
clovers and timothy compose the greater part of a desirable mixture
wherever the clovers and timothy thrive. Probably this condition always
will continue. The clovers are needed to supply nitrogen to the soil
and to put protein into the hay for livestock. They give way, in large
part, or entirely, the second year. Alsike is more nearly perennial
than the red which practically lasts only through its second season,
when its seed crop has been made, and its function performed. The sod
is chiefly timothy in the second season. A little red-top is desirable,
and the percentage should be heaviest for quite wet land or very dry
land. When fertility is the first consideration, and the sod is left
only two or three years, the following mixture is good, and is for one
acre:
Red clover 10 pounds
Alsike 2 pounds
Timothy 8 pounds
Red-top 2 pounds
When a mixed hay is wanted the first year, the following mixture may be
found better for the purpose:
Red clover 6 pounds
Alsike 2 pounds
Timothy 12 pounds
Red-top 2 pounds
Mammoth clover seed may be substituted for the red without change in
number of pounds.
The amount of timothy and red-top in the second mixture suggested calls
for a liberal supply of plant-food, and this is true of any heavy grass
mixture. If fertility is not present, the seeding of grass should be
lighter, but the clover should not be less in amount for a thin soil
than for a good one. The question of fertilizers is discussed in
Chapter XX.
CHAPTER IX
SODS FOR PASTURES
Permanent Pastures.--There is a large total area of land that can be
brought into profitable production of food only by means of pasture
grasses. A small part is too low and moist for tillage, but a larger
part is too rough or too infertile. It can be made to yield profit in
grasses that are harvested without expense by animals. The grasses
afford feed and at the same time protect the soil from waste. The
efficiency of much pasture land is kept low by poor stands of grass,
the encroachment of weeds, bushes, and briers, close grazing, and the
failure to supply fertility. When making a sod for mowing, the aim is
to select varieties of plants that mature near the same time. Pastures
need varieties maturing at different times, and this is a matter under
control when temporary pastures are used. Permanent pasture land soon
becomes occupied by the grasses best fitted to soil conditions or most
able to crowd other plants.
[Illustration: Good Pasture Land in Chester County, Pa.]
Seed-mixtures.--Several varieties of grasses should be used when making
a sod for grazing. They occupy all the surface more quickly and surely
than a single variety, and the pasturage is better. The character of
the soil determines the character of the mixture in large measure. When
land can be well fitted, a heavy seeding is best, but the cost is
nearly prohibitive for thin, rough lands. A brief description of the
leading pasture grasses east of the semi-arid region, and north of the
gulf states, is given:
_Blue-grass._--No other pasture grass equals Kentucky blue-grass
wherever it thrives. It makes a close sod, preventing the growth of
weeds and withstanding tramping, and contains a high percentage of
protein. While it is best adapted to limestone soils, it is grown with
success on clay land outside of limestone areas. It is slow in making a
heavy sod, as a rule, and partly because the seeding is too light on
account of low germination. The rule is to seed with timothy and other
grasses which furnish the greater part of the pasturage for two or
three years. When seeded alone, 20 to 30 pounds of seed per acre should
be used. It may be seeded in the spring or fall, and preferably in
August or September.
_Timothy._--In a mixture of pasture grasses timothy has a place
wherever it thrives. It is not naturally a pasture grass, standing
grazing rather poorly, but it makes a large amount of feed quickly. The
grass is one of the poorest in protein, and the pasturage gains much in
quality when the timothy gives way to blue-grass, as it will in two or
three years if the latter has favoring soil conditions. In most
mixtures it is given a leading place. It may be sown in the spring, but
preferably in the fall, and 15 pounds of seed will be found
satisfactory, when seeded alone.
_Red-top._--If red-top were as palatable to livestock as blue-grass, it
would have one of the most prominent places among our pasture grasses.
It is valuable anyway, thriving where land is too acid for blue-grass
or timothy, or too thin. It is adapted to wet land, and yet is one of
our surest grasses for dry and poor land. It makes a sod that lasts
well, and yields better than most other grasses. Notwithstanding its
lack in palatability, it should be in all pasture mixtures for soils
not in the best tilth. When used alone, 15 pounds of seed per acre
should be sown. The seeding may be made in spring or fall.
_Orchard Grass._--In most mixtures recommended for pasture orchard
grass has a place, but it should be a minor one. It makes early growth
in the spring, which is a point in its favor. It stands shade and also
drouth better than some other grasses, but is not at home in a poor or
wet soil. It grows in bunches, and becomes unpalatable if not promptly
grazed. It needs crowding with other grasses when grown for pasturage.
When seeded alone for hay, 30 pounds of seed per acre may be used.
_Other Seeds._--There are other grasses often recommended, but they
have no wide acceptance. Meadow fescue is a palatable grass that would
be used more often in pasture mixtures if the seed were not high in
price. All land seeded for grazing should have some clover sown for
sake of soil fertility. The alsike remains longer than the red or
mammoth, and is better for undrained, thin, and acid soils.
Yields and Composition of Grasses.--The Ohio station has compared the
yields of various grasses and their composition. The following table is
arranged from its data, as given in Bulletin 225:
+-----------------+----------+---------+----------+
| Name | Average | Pounds | Pounds |
| | Tons Hay | Protein | Protein |
| | per Acre | per | per Acre |
| | | Hundred | |
+-----------------+----------+---------+----------+
| Timothy | 3.49 | 6.38 | 223 |
| Blue-grass | 2.18 | 10.12 | 221 |
| Red-top | 2.81 | 8.53 | 240 |
| Orchard grass | 2.19 | 7.81 | 171 |
| Meadow fescue | 2.10 | 8.97 | 188 |
+-----------------+----------+---------+----------+
Suggested Mixtures for Pastures.--For ordinary conditions, Williams
suggests the following mixture for an acre of land:
Blue-grass 10 pounds
Timothy 6 pounds
Red-top 6 pounds
Orchard grass 4 pounds
Red clover 4 pounds
Alsike clover 2 pounds
For use on rather wet lands, and especially off the limestone, he
suggests:
Red-top 12 pounds
Blue-grass 8 pounds
Timothy 4 pounds
Alsike clover 4 pounds
Hunt recommends the following as a basis, to be modified to suit
varying conditions:
Timothy 15 pounds
Kentucky blue-grass 10 pounds
Meadow fescue 2 pounds
Red clover 4 pounds
Alsike clover 3 pounds
White clover 2 pounds
The Cornell station recommends the following for good land:
Timothy 8 to 12 pounds
Kentucky blue-grass 4 pounds
Meadow fescue 1 to 4 pounds
Orchard grass 1 to 4 pounds
Red clover 6 pounds
Alsike clover 3 pounds
White clover 1 to 2 pounds
For poor lands it recommends this mixture:
Timothy 8 to 12 pounds
Red-top 4 pounds
Canadian blue-grass 4 pounds
Red clover 6 pounds
Alsike clover 3 pounds
White clover 1 pound
Zinn, of West Virginia, recommends the following mixture for permanent
pasture:
Timothy 4 pounds
Red-top 4 pounds
Orchard grass 4 pounds
Kentucky blue-grass 7 pounds
Red clover 2 pounds
Alsike clover 2 pounds
White clover 1 pound
Renewal of Permanent Pastures.--There is much pasture land that could
not be broken with profit for reseeding. There is neither time, nor
money, nor opportunity at the owner's hand for this purpose, and often
the loss of soil resulting from washing would be a bar if the labor
would cost nothing. The renewal of such grass lands can be made with
profit if pernicious weeds are not in the way. Plant-food, lime, and
grass seed are wanted. A disk or sharp spike-tooth harrow, used in
early spring or after an August rain, will give some fresh earth for
covering the seeds. A complete fertilizer always is needed. The clovers
should go into the seed-mixture used.
[Illustration: Sheep on a New York farm.]
Destroying Bushes.--The absence of sheep is evident in the appearance
of the greater area of permanent pasture in the mountainous regions of
the eastern states. Bushes, briers, and other weeds must be destroyed
if pasture land would be kept in a profitable state, and only the sheep
or the goat is the fully efficient aid of man in caring for such land.
The presence of dogs makes the tariff on wool, or lack of it, a minor
matter. The cost to the country, in indirect effect upon pastures only,
due to unrestrained dogs, is incalculable. The maintenance of good sods
without sheep is a problem without solution in some regions.
Close Grazing.--Much harm results from turning livestock on pastures
too early in the spring. The ground is kept soft by spring rains, and
the hoofs cut the turf. The grass needs its first leaves to enable it
to make rapid growth, and the first grass of spring is not nutritious.
Close grazing is harmful, exposing the soil to the sun and robbing it
of moisture. When winter comes, there should be sufficient grass to
serve as a mulch to the roots. It acts like a coat of manure, giving
new life to the plants the next spring. Good sods are not easily or
quickly made, and when they have been secured on land unfit for the
plow, their value measures the value of the land itself.
CHAPTER X
THE COWPEA
A Southern Legume.--The soils of the cold north are protected from
leaching during the winter by the action of frost. The plant-food is
locked up safely for another year when nature ceases her work of
production for the year. Farther south, in the center of the corn belt,
there are leaching periods in fall and spring and oftentimes during the
winter, but winter wheat thrives and, in ordinary crop-rotations,
covers much of the land that might otherwise lose plant-food. As we
pass from the northern to the southern states, the preservation of soil
fertility grows more difficult and at the same time the restoration of
humus becomes easier. The heat makes easy the change of organic matter
to soluble forms, and the rains cause waste, but the climate favors
plants that replace rapidly what is lost. In the work of supplying land
with fertility, directly and indirectly, the southern cowpea has an
important place. It is to the south what red clover is to the north,
and it overlaps part of the red-clover belt, having a rightful place as
far north as the Ohio Valley, and portions of Pennsylvania.
Characteristics.--The cowpea is closely related to the bean, and is
very unlike the Canada pea, which is a true pea, thriving only in a
cool climate. The cowpea has been grown in the southern states over one
hundred years, and the acreage is large, but it never has come into the
full use it deserves. Being a legume, it stores up nitrogen taken from
the air, and unlike red clover it makes its full growth within a short
period of time. It can grow on land too infertile for most kinds of
valuable plants, and on better land. The vines can crowd out nearly all
varieties of weeds. The roots go to a good depth and are thickly
covered with the nodules of nitrogen-gathering bacteria.
Varieties.--There are many varieties of the cowpea, and confusion of
names prevails, although some stations have done good service in
identification of individuals carrying a number of names. The very
quick-maturing varieties adapted to northern conditions do not make as
much foliage as the rank-growing ones that require a relatively long
season, but some of them are heavy producers of seed.
There are varieties requiring six months of southern heat to bring them
to maturity, and some failures attending the introduction of the cowpea
into more northern latitudes have been due to bad selection. A few
varieties reach maturity within two months of hot weather.
The trailing habit is affected by the soil, the bunch varieties tending
to trail when grown on fertile land. When the crop is wanted for seed,
the peas that do not trail heavily will prove more satisfactory. The
selection of variety is a matter of latitude and purpose, exactly as it
is with corn.
Fertilizing Value.--A heavy growth of the cowpea is worth as much to
the soil as a good crop of red clover. When the equivalent of two tons
of hay is produced, the roots and vines contain nearly as much
plant-food as the roots and first crop of medium red clover that makes
two tons of hay. Some analyses show a higher percentage of protein in
cowpea hay than in clover hay, and the experience of many stockmen
indicates that such is the case. The roots and stubble have somewhat
less fertilizing power than in the case of the clover, and all thin
soils should have the entire plant, or the manure from the hay, saved
without loss.
Comparison is made on the basis of equal adaptability of soil and
climate to clover and the cowpea. Going southward, the cowpea has the
advantage, and northward the clover gains. It is in the overlapping
belt that both should be freely used. The cowpea has distinct advantage
over the clover in its ability to supply nitrogen and organic matter
within a few months, and in its adaptation to very poor soils where
clover would not make much growth. As a catch crop it has great value.
Affecting Physical Condition.--The cowpea has marked influence upon the
physical condition of heavy soils, even when the vines are not plowed
down. This is due in some degree to the roots, and probably more to the
mulching effect of the vines during their growth. Heavy soils are made
much more mellow by the cowpea, and when the crop is removed for hay,
the stubble-land is easily prepared for a seeding to grass or small
grain. When the growth is plowed down, the soil may be made too loose
for seeding to small grain, but is put into prime condition for a
tilled crop.
Planting.--The land should be fitted as it is for corn. Light, sandy
soils require little preparation, and too often the seeding is made in
a woefully careless manner, the chief dependence being placed upon
sufficiently deep covering to insure germination. The ground should be
fitted as well as it is for a cash crop, being made fine and smooth. A
grain drill makes the seeding in a satisfactory manner, and the seed
may be drilled solid or in rows for cultivation. When the crop is grown
as a fertilizer or for hay, solid drilling is good, and about five
pecks of seed gives a good stand of plants if peas are sound. Much
cowpea seed is low in germination power, and the buyer should exercise
caution. When a seed crop is wanted, two to three pecks of seed per
acre, placed in drills 28 to 32 inches apart, make an excellent
seeding, as cultivation can be given. The amount of seed varies with
the variety. In northern latitudes a warm soil is to be desired, and
cultivation gives better results when a seeding to wheat will be made
on the pea-stubble.
There is evidence that the cowpea can make a heavy growth in soils too
deficient in lime for red clover, and it gained its first prominence in
southern Ohio on land that was failing to grow clover. It is the plant
of adversity as well as prosperity, adding rich organic matter to thin
soils, but making its full returns under better conditions. Lime
applications on acid soils give increase in yields. Its one absolute
requirement is heat, and in a cold summer its northern limit is
markedly depressed.
Inoculation.--The inoculation of the soil with cowpea bacteria is
necessary to best results in most regions new to the plant.
Self-inoculation is quicker in the cowpea than in alfalfa because the
vines carry some soil on them, and thus the dust in the seed crop may
be rich in bacteria. However, most new seedings of the cowpea do not
show a large number of nodules on the plant roots, and inoculation
pays. In some cases it makes the difference between failure and
success. Two hundred pounds of soil from an old field should be well
harrowed into each acre of land when preparing for a cowpea seeding in
a new region. The soils of the southern states contain the bacteria
just as the states in the clover belt are supplied with clover
bacteria.
Fertilizers.--The light soils of Maryland, New Jersey, and the southern
states are not naturally rich in phosphoric acid or potash. The cowpea
can draw its nitrogen from the air, but on all thin land it pays to use
200 to 300 pounds of acid phosphate and 50 pounds of muriate of potash
per acre for this crop which should have a luxuriant growth for the
soil's benefit. Such use of fertilizers is more profitable than their
use on the crop which follows.
Harvesting with Livestock.--When the cowpea is made into hay, there is
always danger that the most of the plant-food contained in it never
will get back to the soil on account of a careless handling of the
manure. The practice of pasturing with cows and hogs is excellent. The
feed is rich, and the manure is left on the ground. There is a saving
of labor.
If the full fertilizing value is wanted for the soil, the crop should
be plowed down. The trailing varieties form a tangled mass that cannot
be handled by an ordinary breaking-plow, but a stalk-cutter, run in the
direction the plow will follow, makes plowing possible. Pasturing with
cattle and hogs sufficiently to reduce the growth so that a plow can be
used is good practice.
The Cowpea for Hay.--The hay is one of our most palatable
feeding-stuffs. Livestock may reject it the first time it is put into
the manger, but a taste for it is quickly acquired, and soon it is
eaten greedily. The high content of protein makes it exceptionally
valuable for young animals and milk cows, and the manure contains a
high percentage of nitrogen. The difficulty in making the hay is a
drawback, but this is over-rated. While rain discolors the vines and
makes them unattractive in appearance, the hay remains more palatable
and nutritious than good timothy, if the leaves are not lost in curing.
When the first pods turn yellow, the crop should be harvested. The
vines can be left in the swath until the top leaves begin to burn and
then be put into windrows with a sulky hay-rake. The windrows should be
small, the rake merely serving to invert half the vines upon the other
half, bringing new surface to the sun. After another day of curing, the
windrows should be broken up into bunches no larger than can be pitched
upon the wagon by a workman, thus saving the trouble of disentangling
the vines. If rain comes, the bunches should be inverted the following
day. In dry, hot weather the curing proceeds rapidly, while in cooler
latitudes or cloudy weather the curing may require a week. The chief
point is to prevent undue exposure of the leaves to the sun, and this
is accomplished by the turning. The hay will mold in the mow if not
thoroughly well cured, unless placed in a large body in a deep, close
mow that excludes the air. Some farmers use the latter method
successfully, but the experimenter with the cowpea usually will fail,
and should prefer thorough field curing, at the risk of some damage
from rain and sun. The leaves are the most nutritious part of the
plant, excepting the seed.
As a Catch Crop.--A leading use of the cowpea is that of a catch crop,
either between other crops or in a growing crop, such as corn. Early
maturing varieties can be brought in between main crops of the rotation
in warm latitudes. The growth prevents the leaching of plant-food,
shades the ground, adds nitrogen to the soil, smothers weeds, and
produces material that is valuable as feed for livestock or an addition
of organic matter to the soil. When the time that can be devoted to the
crop is short, an early variety should be selected because its vines
are far more valuable to the soil than an equal volume of a
rank-growing variety that is not near maturity.
[Illustration: The cowpea seeded at the last cultivation of corn in the
Great Kanawha Valley, W. Va.]
If this legume were used whenever opportunity afforded along the
southern border of our northern states, and throughout the south, the
faded color of soils, resulting from leaching rains, would be replaced
by the darker colors that mark the presence of rich organic matter. It
is one of nature's best allies in the maintenance of soil fertility.
CHAPTER XI
OTHER LEGUMES AND CEREAL CATCH CROPS
The Soybean.--The soybean is gaining a place among the valuable legumes
of the United States, and the acreage is increasing as its merits
become known to all. Its northern limits of profitable production are
much farther north than those of the cowpea, and approach those of
corn. In the south it is gaining friends. Some of the advantages of the
soybean over the cowpea, as found by the Tennessee station, may be
stated as follows:
1. Greater seed production in case of fertile soils.
2. Less sensitiveness to cold in spring and fall.
3. Greater feeding value of the seed.
On the other hand, a stand of cowpea plants is surer in the case of
soils that crust, and germination runs higher. Its climbing habit makes
it better suited for growing with corn for forage. A less amount of
leaves is lost in curing.
Fertility Value.--There are so many varieties of the soybean and the
cowpea, and adaptation to soil and climate varies so widely, that a
fair comparison is difficult to make. In cool latitudes the soybean is
recognized as distinctly more profitable, making larger yields of vines
and of seed. Where adaptation is equal, the cowpea makes a slightly
larger growth of vines for hay, but the soybean gives a much richer lot
of seed for use as grain.
When soil fertility is the chief consideration, the adaptation of
climate and soil should decide our choice between these two legumes.
There is no serious difference where conditions for each are equally
good. In cool latitudes the soybean should be chosen. In the Ohio
Valley it is usually to be preferred. The greater part of the organic
matter and the plant-food is stored in the vines and seed.
Feeding Value.--The soybean makes a rich hay, surpassing clover, but it
is coarse, and its unattractive appearance has caused many farmers to
condemn it without trial. Livestock eat it greedily, and it is one of
our richest coarse feeds. The curing is more difficult than in the case
of the cowpea because the leaves drop early, and the plants must be
harvested before they approach maturity.
Probably the large yield of rich seed is the most important feature of
the soybean crop. A ton of the seed contains as much protein as a ton
of old-process oil meal, and three fourths as much as a ton of
cottonseed meal. A good crop of the soybean will yield 18 to 20 bushels
of seed, and as the nitrogen may be obtained chiefly from the air, the
protein from this crop will come to be a leading substitute for
purchased protein feeds.
Varieties.--There are many varieties of the soybean, and their
characteristics are modified by climatic conditions. Each region will
find the varieties best suited to its purposes by tests. When hay is
wanted, the variety should have fine stems and a leafy habit of growth.
It may not be a good producer of seed, or able to hold the seed
unshattered. The harvesting should be done when some lower leaves turn
brown and before the pods are half filled. This stage of maturity
should be reached early enough in the fall to insure some hot days for
making the hay, and to permit harvesting in time for seeding to wheat.
The preparation for wheat is made with the harrow and roller or plank
drag.
When the soybean is grown for seed, the variety should hold the peas
without undue shattering, and an erect grower is more easily handled
without loss of the crop. Varieties for regions will vary, as do
varieties of corn, according to climate.
The Planting.--Early varieties of the soybean in the south can be
planted as late as mid-summer, but farther north a profitable crop
requires nearly all of the summer heat. The planting may be made soon
after the usual time of planting corn, or whenever the ground has
become warm. The preparation of the soil should be more thorough than
that often given the cowpea. Solid drilling of five pecks of seed per
acre is satisfactory when the crop is for fertilizing purposes only,
and gives an excellent hay on land free of weeds. When the crop is
wanted for hay, however, wheat usually will follow, and it is much
better to plant in rows and to give two or three cultivations so that
the ground may be easily prepared for the wheat.
A seed crop should be grown in rows. Three pecks of seed in rows 28
inches apart is the usual amount.
The soybean does not come up through a crusted surface as well as most
other plants, and planting should not be made immediately before a
rain. The plants are tender and easily injured by use of a weeder.
The fertilizer requirement is like that of the cowpea. An application
of 200 pounds of acid phosphate per acre should be given, and the
addition of 50 pounds of muriate of potash often pays.
Harvesting.--The soybean is not an easy crop to handle without loss.
When grown for seed, the tendency of the pods to split and to drop the
seed compels early cutting, and that makes curing more difficult. The
mower is the only practical harvester on most farms, and the swath must
be turned out of the way of the horses to save tramping. A
side-delivery attachment can do the work. This is the best practice
when cut for hay. When used for mixing with corn in a silo, the
self-binder is satisfactory. The hay and seed crop must have thorough
field-curing in windrow and bunches, and the harvest comes in a season
when cold rains may prevail. This disadvantage of one of our most
valuable crops is to be taken into account, but it will not prevent
rapid increase in acreage as the merit of the soybean becomes known.
The Canada Pea.--Among field peas there are many varieties, but the one
chiefly grown in the United States under the general name of the Canada
pea is the Golden Vine. It makes a green forage or hay that is rich in
protein. Usually it is grown with oats, giving a hay nearly as
nutritious as that of clover. The crop is adapted to cold latitudes,
and the planting should be made as early in the spring as possible.
Fall-plowing of the land is to be advised on this account. A good
method of seeding is to drill in six pecks of the pea seed to a depth
of four inches, and then to drill in six pecks of oats.
The crop should be cut for hay when the oats are in the milk stage. At
this time the peas are forming pods. The hay is not easily made, but is
specially valuable for dairy cows.
There is no profitable place for the Canada pea in crop-rotations
farther south than the true oat-crop belt, except as a green-forage
crop. The soybean and red clover have greater usefulness in the center
of the corn belt.
Vetch.--A variety of vetch known as winter, sand, or hairy vetch is
coming into great usefulness as a catch crop. It is a winter annual,
and being a legume, it has special value as a fertilizing crop. It is
more hardy than crimson clover, and is grown as far north as winter
wheat. The seeding is made in August in the north, and when grown for
hay or seed, it needs rye or wheat to hold it up. Rye and vetch make a
rich and early green forage crop, and the proportion in which they are
seeded varies widely in practice. Six pecks of rye and 15 pounds of
vetch make an excellent seeding per acre.
When grown for seed, one to two pecks of rye and 20 to 30 pounds of
vetch may be used. The rye can be fairly well separated from the vetch
by use of a fanning-mill or an endless belt of felt so inclined that
the round vetch seed will roll down, while the rye sticks to the felt
and is carried over.
Vetch is excellent as a fertilizing crop, adding a great amount of
nitrogen to the soil when plowed down in May. If the seed were cheap,
its use would become much more common. Thirty pounds should be used
when seeding alone after summer crops or in corn. Farmers should
produce the seed for their farms, and use it freely. When sown for
seed, September first is a good date for the north. The seed matures in
June.
As vetch matures with wheat, it may easily become a weed on farms
devoted largely to small grain, but it is not to be feared where tilled
crops and sods are the chief consideration. Inoculation is needed for
best results, as in the case with other legumes new to a region.
Sweet Clover.--Much interest has been aroused within recent years in
sweet clover, a legume that formerly was regarded as a more or less
pernicious weed. Its friends regard it as a promising forage crop, but
too little is definitely known to permit its advocacy here except as a
soil-builder in the case of poor land that is not too deficient in lime
to permit good growth. Experiments have shown that a taste for this
bitter plant can be acquired by livestock, and it is nearly as
nutritious as alfalfa when cut before it becomes coarse and woody. It
is a strong grower, sending its roots well down into the subsoil, and
its great ability to secure nitrogen from the air enables it to make a
very heavy growth of top. The yield in forage usually exceeds that of
the clovers.
Its most peculiar characteristic is its ability to thrive in a poor,
compact soil that contains little humus. It may be seen in thrifty
condition on roadsides and in waste places that seemingly would not
support other plants. Laying aside all consideration of its
possibilities as a forage crop, it will come into greater popularity as
a soil-builder on thin land. It is found usually on land of limestone
formation, and shares with other legumes a liking for lime, but it has
been grown successfully in regions that are known to have a lime
deficiency.
There are two biennial varieties and one annual. The biennial having
white blossoms is the one most commonly seen, but the smaller variety
with yellow blossoms is more leafy and palatable. The larger variety is
the better fertilizer.
The seed does not germinate readily, and 20 to 30 pounds is used per
acre. The soil should be compact, and the seeding can be made in the
spring with a cover crop, or in August by itself. Inoculation is
necessary if the right bacteria are not present. Soil from an alfalfa
field will serve for inoculation.
An effort should be made to grow sweet clover on all infertile
hillsides that are lying bare. It stops washing and paves the way for a
sod of nutritious grasses.
Rye as a Cover Crop.--As has been stated elsewhere, the plant that
stores nitrogen in its organic matter is most desirable, but the
greater part of the soil's stock of humus did not come through legumes.
Among the good cover crops is rye, both on account of its ability to
grow under adverse conditions and because it produces a large amount of
material for the soil. When seeded in the early fall, its roots fill
the soil the following spring, and the tops furnish all the material
that can be plowed down with safety. In northern latitudes it is the
most dependable of all winter cover crops, making some growth in poorly
prepared seed-beds and on thin land. The most value is obtained from
early seedings, thus securing a good fall growth. Two bushels of seed
are sufficient in good ground seeded ten weeks before winter begins,
but two or three pecks should be added to this amount if the rye can be
given only a few weeks of growth before frost locks up the soil. Rye
can grow in warm spells of winter, and starts early in the spring. It
uses up some available fertility that might otherwise be lost, and
releases it when it rots in the ground.
When to plow Down.--If rye has made a good growth before spring, the
roots run deeper than the plow goes, and holds the soil much like a
grass sod. In such a case the plowing may be made early in the spring
without regard to the rye, though organic matter increases rapidly day
by day if the rye is permitted to grow. As a rule, it is safest to plow
down before the plants are eighteen inches high. They dry land out
rapidly, and any mass of matter in the bottom of the furrow interferes
with the rise of water from the subsoil. When the land is wanted for
oats or corn, a jointer should be used on the plow to insure burying
all the crop.
Buckwheat.--An excellent crop for green-manuring is buckwheat. It has
such unusual ability to grow in a poor soil that the farmer who makes
free use of it as a grain crop never boasts of acreage planted,
assuming that his land will not be highly regarded if known to be
devoted chiefly to buckwheat. It does not withstand heat well,
especially from period of blossoming to maturity, and therefore is
restricted to cool latitudes. When grown for grain, it usually is not
planted until July, and matures a crop in a shorter period than any
other grain. It is sensitive to frost, but may be planted as soon as
the ground is warm, and will give a good body of matter for plowing
down within eight weeks. The root growth is not extensive, but the crop
leaves naturally heavy soils more mellow, and it is an excellent
cleansing crop for weed-infested fields. It makes a less heavy growth
than rye, but can be used at a time of the year that rye would fail.
There is time in a single season to grow two crops of buckwheat for
green-manuring, turning the first crop down when the blossoms appear.
Oats.--When a fall growth is wanted for the soil, and it is preferred
that the plants be dead in the spring, oats make a good catch crop.
Thin land which is wanted for seeding to wheat and grass in the fall,
or for timothy and clover seeding in August, may use oats as a spring
cover crop. A large amount of humus-making material may be gained by
this means. The only danger lies in the effect upon soil moisture. The
oat crop uses up the water freely in its growth, and when permitted to
form heads before being plowed down, the mass of material in the bottom
of the furrow does not rot quickly enough to induce the rise of water
from the subsoil. The land should be plowed early enough to permit a
solid seed-bed to be made.
CHAPTER XII
STABLE MANURE
Livestock Farming.--The fertility of the soil is most safely guarded in
regions devoted to livestock farming. "Selling everything off the farm"
is a practice associated in the public mind with soil poverty. It is a
rule with few exceptions that the absence of livestock on the farm is
an index of gradual reduction in the productive power of the land.
Generally speaking, the farmers who feed the most of their crops on the
farm are maintaining fertility, and those who do not feed their crops
on the farm have been making drafts upon the soil's stores of available
plant-food that are evidenced in a reduction of yields. These
statements will have the assent of all careful observers. The inference
has been that the maintenance of fertility requires the return to the
land of all the manure that would result from feeding its crops on the
farm. We know that by such feeding we can return to the fields at least
four fifths of all the plant-food taken out by the crops, and we
loosely reason that such a scheme is demanded by nature. The
maintenance of fertility involves good arithmetic, and a plant must
have certain weights of mineral elements at command before it can grow,
but it is not true that the productive power of land is chiefly
dependent upon the return to it in manure of all the fertility removed
by its crops. If this were true, meat and other animal products would
be the sole food supply of the world's markets.
[Illustration: Texas calves on an Ohio farm.]
The Place for Cattle.--There are general trends in human practice that
cannot be changed by man. A change in human diet that makes the
percentage of meat lower will not come through propaganda, but there
are forces at work that will restrict the consumption of meat by the
individual. The increase in population makes heavier demand for food.
Armsby has shown that the fattening steer returns to man for food only
3 per cent of the energy value of the corn consumed by it, and in
pork-production this percentage scarcely rises to 16. This is the
reason meat-making animals give way before increase in population in
congested countries. Their office becomes, more and more, the
conversion of products inedible to man to edible products. In our
country their number will increase, doubtless, for a long period of
time, finding their places more surely on eastern farms rather than on
western ranches. They must find the cheaper land, and that is no longer
confined to the west. They must be where coarse materials, inedible to
man, are found, and that is on eastern as well as on western farms.
Their office will not be the conversion of crops into manure, but the
conversion of coarse materials into human food in the form of meat or
milk. This is the trend, and while the consummation may happily be far
in the future, its consideration helps us to an appreciation of the
facts regarding nature's provision for maintaining the productiveness
of the soil.
Sales off the Farm.--The day is now here when the major portion of
human food must be provided in grain and vegetables and fruit, and the
demand for hay and grain for animals off the farm is very large. Fiber
products likewise must be supplied. The draft upon the soil is heavy,
but it must be good farm practice to supply bread and vegetables and
fruit to the 70 per cent of our population that is not on farms. The
great majority of farmers do not feed all their crops to livestock, and
the amount of food-stuffs, for human beings and animals, that is now
going off the farms is none too great.
Many farmers who incline to believe that they are safely guarding
fertility by feeding the most of their crops are not returning to the
fields one third of the plant-food that their crops remove. There is no
virtue in feeding when the manure is permitted to waste away. The
losses in stable and barnyard, the wastes from bad distribution by
animals, and the sales from the farm of some crops, animals, and milk,
lead to the estimate that one half of the farms on which livestock is
kept do not give to the fields in the form of manure over 30 per cent
of the fertility taken out of them by crops. This estimate, for which
no accurate data is possible, probably is too high. The sales of food
for man and animal are a necessity, and the scheme of farming involving
such sales is right, provided the farmer makes use of other supplies of
fertility. The area devoted to such sales will grow greater because
human needs are imperative. Livestock will become more and more a means
of working over the material that man cannot eat--the grass, hay,
stalks, by-products in manufacture, and coarse grains. The demand for
meat and milk will lead to careful conversion of material into this
form of food, and the animals on eastern farms will increase in number
for a time, while sales of grain and vegetables grow greater. The draft
upon soil fertility through sales must increase because every pound of
material sold from the farm carries plant-food in it.
The Value of Manure.--It is not possible to put a commercial valuation
upon farm manures that may be a sure guide to any farmer. The value
depends upon what the individual can get out of it in crops and
improved soil conditions. It is rather idle to say that the annual
product of a horse in the form of manure is $30, or more or less, even
when an analysis shows that the nitrogen, phosphoric acid, and potash
contained in it are worth that sum when valued at the market prices of
those plant constituents. If the total amount of fertility found in the
voidings of all the animals of the farm were provided in a pile of
commercial fertilizer containing the same amount of each plant
constituent, its worth to the farmer would depend upon his ability to
convert all that fertility into crops at a profit. There are farmers so
situated in respect to soils, crops, and markets that they can make a
good profit from an investment of $30 in the total liquid and solid
voidings of a horse for a year. On the other hand, there are many who
would fail. The values usually given are relative and suggestive. They
are aids in forming judgment. Actual value on the farm depends much on
the man.
The Content of Manure.--When the crops of a farm are fed, the manure
contains nearly all the plant-food that went originally into the crops.
In the case of idle work-horses on a maintenance ration, the manure
contains practically all the plant-food. Cows giving milk remove some
fertility, and a growing calf or colt may take out 30 per cent. There
is some waste beyond control, but when manure is made on tight floors
with good bedding, and is drawn to the field fast as made, on the
average it carries back to the soil fully four fifths of the plant-food
that existed in the feed. Disregarding all cash valuations for the
moment, here is an index of value that should be sufficient in itself
to encourage the feeding of crops on the farm and the careful saving of
the manure. When one can market his crops to animals on the farm at
their cash value, and at the same time retain for his fields four
fifths of all the fertility, he is like a manufacturer who can use much
of his raw material over and over again. The value is in the manure,
and full appreciation is lacking only because a majority of farms do
not provide for careful saving of its valuable constituents.
Relative Values.--The plant-food content of manure is determined
chiefly by the feed. The animals add nothing: they subtract. The kind
of animals consuming the feed does not affect materially the value of
the manure made from it, if the animals are mature and not giving milk.
The manures from the various kinds of animals differ in value per ton
because the feeds differ in character and the manure varies in
percentage of water. On an average, however, the total annual product
of manure from farm animals, per 1000 pounds of live weight, does not
vary widely in value. The rich protein feeds given the cow, and the
heavy feeding, more than make amends for the fertility that goes into
the milk, and her annual product, per 1000 pounds of live weight, may
exceed in value that of the horse by 25 per cent. This is likewise true
of the pig, figured on the 1000-pound basis, while in the case of the
sheep the value, per 1000 pounds of live weight, is near that of the
horse.
[Illustration: In the fertile Miami Valley, Ohio.]
These variations are not wide enough to have great importance to the
livestock farmer. The manure represents to him four fifths of all the
fertility that was contained by the feed he gave the various animals.
They added no plant-food, and they took away only a fraction that was
not large. They converted the crops into a form of plant-food that
either is available or can become so quickly enough, and in addition to
the nitrogen, phosphoric acid, and potash that would have a high
valuation in a commercial fertilizer, there is a body of organic matter
that affects the physical condition of the soil favorably. The manure
also promotes the multiplication of friendly soil bacteria. Its
possibilities are so great that the inference of many farmers that no
successful agriculture can be maintained without it is very natural.
Amount of Manure.--Vivian states that the amount of manure that may be
made from feed can be determined by multiplying the total weight of dry
matter in the feed by 3. This assumes that bedding will be used in
sufficient amount to absorb the urine, and that will require material
containing one fourth as much dry matter as there is in the feed. When
the amount of hay and grain is known, and the dry matter in all
succulent feed is estimated, the total product of manure in tons can be
arrived at with fair accuracy.
Analysis of Manure.--As has been stated, the content of the manure must
depend chiefly upon the character of the feed. We are accustomed to
combine feeding stuffs in differing proportions for horses, cows, pigs,
and sheep. Van Slyke names the following approximate percentages of
plant-food constituents in fresh excrements of farm animals, the solid
and liquid being mixed:
+----------+----------+------------+----------+
| Animal | Per Cent | Per Cent | Per Cent |
| | Nitrogen | Phosphoric | Potash |
| | | Acid | |
+----------+----------+------------+----------+
| Horse | 0.70 | 0.25 | 0.55 |
| Cow | 0.60 | 0.15 | 0.45 |
| Pig | 0.50 | 0.35 | 0.40 |
| Sheep | 0.95 | 0.35 | 1.00 |
| Hen | 1.00 | 0.80 | 0.40 |
+----------+----------+------------+----------+
He estimates that one ton of average mixed stable manure, inclusive of
absorbents, contains approximately 10 pounds of nitrogen, 5 pounds of
phosphoric acid, and 10 pounds of potash.
CHAPTER XIII
CARE OF STABLE MANURE
Common Source of Losses.--When we bear in mind that four fifths of all
the fertility removed from the land in the grains and coarse stuffs fed
on the farm may be recovered from the animals and returned to the soil,
we can appreciate the consideration that the care of manure should have
on every farm. The careless methods that prevail in most sections of
the country are an inheritance from the day when soils were new and
full of fertility. These methods continue partly through a lack of
confidence in the statements that the liquid portion of animal
excrements, in average mixed stable manure, has nearly as great value
as the solid portion. If this fact were accepted, many of the losses
would be stopped. Another reason for continuance of careless methods is
failure to appreciate that the soluble portion of manure is the highly
valuable part, and that leaching in the barnyard carries away value
more rapidly than decrease in volume of manure indicates. The widely
demonstrated facts do not have effective acceptance, and enormous loss
continues.
Thorne found that manure placed in flat piles in the barnyard in
January, and allowed to lie until April, lost one third of its value.
Under the conditions prevailing on many farms the loss suffered by
exposure of manure is far greater.
[Illustration: Concrete stable floors.]
Caring for Liquid Manure.--If all manure were in solids, one great
difficulty in caring for it would not exist. The nitrogen is the most
valuable element in manure, and two fifths of all of it in horse manure
is found in the liquid. In the case of cow manure, over one half of the
nitrogen is found in the liquid. More than this, a pound of nitrogen in
the liquid has greater value than a pound in the solid because of its
nearly immediate availability. There is only one good way of caring for
the liquids, and that is by use of absorbents on tight floors or in
tight gutters. American farmers find cisterns and similar devices
nuisances. The first consideration is to make the floor water-tight,
and clay will not do this. The virtues of puddled clay have had many
advocates, but examination of clay floors after use will show that
valuable constituents of the manure have been escaping. The soils of
the country cannot afford the loss, and careful farm management
requires acceptance of the truth that a tight floor is as necessary to
the stable as to the granary. The difficulty in supplying a sufficient
amount of absorbents on tight floors only emphasizes the loss where
floors are not water-tight.
Use of Preservatives.--The use of land-plaster in stables helps to
prevent loss of the nitrogen-content through fermentation. Its value
does not lie chiefly in physical action as an absorbent, but the
beneficial results come through chemical action. The volatile part of
the manure is changed into a more stable form. In recent years this
preservative has fallen somewhat into disuse, as acid phosphate
contains like material and also supplies phosphoric acid to the manure.
The phosphoric acid content of stable manure is too low for all soils,
and the reenforcement by means of acid phosphate would be good practice
even if there were no preservative effect. The use of fifty pounds of
acid phosphate to each ton of manure will assist materially in
preserving the nitrogen, and the gain in phosphoric acid will repay all
the cost. It should be used daily on the moist manure, as made in the
stable, and preferably just before bedding is added, so that the
phosphate will not come into direct contact with the feet of the
animals. Some stockmen prefer the use of acid phosphate and kainit
mixed half-and-half. The latter is a carrier of potash, and is a
preservative of nitrogen.
The use of ground rock-phosphate in stables is coming into use in some
localities, chiefly through the recommendation that it be mixed with
manure to secure availability of its own plant-food. It is not a
preservative except in so far as it acts physically as an absorbent. It
should not displace acid phosphate in stables, the preservation of
nitrogen in the manure being the vital matter.
Spreading as Made.--When farm conditions make it feasible to draw and
spread manure fast as made, the danger of heavy loss in storing is
escaped. There is evidence that no appreciable escape of fertility
occurs when manure is spread on land that is not covered with ice. The
phosphoric acid and potash are minerals, and leach into the soil. The
nitrogen does not change into a gas in any appreciable amount when
spread over the surface, and it likewise leaches into the soil. There
are soils in which the decay of the organic matter would have a more
beneficial effect than the rotting upon the surface, it may be, but the
mulching effect of the manure is valuable. There should be no doubt
that the loss from manure is kept to a minimum when it goes directly to
the soil. In some latitudes the snow and ice oftentimes prevent
spreading, or make it inadvisable, and in many farm schemes it is
desirable to hold manure for special fields and crops. Some means of
storing manure must be provided in these instances.
The Covered Yard.--If the possible value of manure were realized,
provision for its care would be made as promptly and surely as
provision for the care of a harvested crop. There are only three
conditions that must be provided in order that manure may be preserved
without much loss. The manure must be protected from leaching rains, it
must be kept moist, and air must be excluded. The exposure of stable
manure to the processes of fermentation and leaching, produces a waste
that is believed to amount to several hundreds of millions of dollars
in the United States annually. The day will come when no farmer will be
willing to share heavily in a loss from this source, but will either
spread manure fast as made or provide a roof for the stored manure. An
absolutely tight floor is not so great a necessity as it is in the
stable, because the amount of moisture is under control, but many
farmers prefer to make concrete floors for the manure-shed and thus to
guard against any loss from leaching. The chief cost may be confined to
the roof.
A better plan is to inclose three sides, making them so tight that all
drafts will be prevented, and to use the shed as a place of exercise
for cows or other livestock. We have learned within recent years that
such an inclosure is more healthful and comfortable for cattle than
stalls in an inclosed building, no matter how cold the weather may be.
The fresh air without any drafts, and the liberty of movement, are
needed. This shed should be connected with the stable, and on its floor
the manure from the stables may be spread daily. It should be scattered
evenly over the surface, and the mass can be kept firm by the tramping
of the animals. It may be necessary to add some water at intervals to
keep the mass sufficiently moist. The water excludes air and assists in
holding harmful fermentation in check.
Harmless Fermentation.--There is a kind of fermentation in manure that
goes on in the absence of air. It is due to bacteria that break up the
organic matter, producing rotted manure. This is not attended by much
loss, and proceeds beneath the surface of the moist and packed mass.
Manure properly controlled under a roof goes into prime condition for
spreading later in the season. The only danger is neglect, and
especially when the livestock is removed to the pasture fields in the
spring. If no water is added from time to time, hot fermentation
replaces the harmless kind because air can penetrate through the bed of
manure. Compactness and moisture can save the plant-food with small
loss throughout the summer, and a body of good manure is available when
needed for top-dressing land in the summer.
Rotted Manure.--Mixed stable manure contains in a ton as many pounds of
potash as it does of nitrogen, and yet we speak of it as a highly
nitrogenous fertilizer. When fresh manure has suffered no loss of the
liquid part, much of its nitrogen is almost immediately available. The
nitrogen in the urine is in soluble forms, and fermentation quickly
occurs. When manure is used on grass, it cannot be too fresh, as the
immediate action of the nitrogen is desirable. Vegetable growers often
prefer a slower and more continuous action, and the rotting of manure
under right conditions changes the liquid nitrogen into compounds that
act more slowly.
The solid material in horse manure contains less water than that of the
cow, and this absence of water permits quick fermentation when air is
present. The use of large quantities of such manure per acre is not
liked by vegetable-growers. Rotting under control in a covered barnyard
has a beneficial effect for this reason when a hot manure is not
wanted. The covered shed costs some money, and there is a loss
estimated at 10 per cent under the best conditions, but when manure
cannot be drawn fast as made, there is compensation in improved
condition for certain soils and crops.
Composts.--The compost, involving the handling of manure and soil, has
no rightful place on the average farm. The gardener or trucker using
great quantities of manure per acre must let some of the fermentation
occur before he incorporates it with the soil, or harm will result. He
wants reduction in volume, and such change in character that it will
add to the retentive character of the soil respecting moisture instead
of drying the soil out. He can afford all the labor of piling the
manure with layers of sods or other material, and the turning to secure
mixing. It is his business to watch it so that loss will not occur.
The farmer uses manure in smaller quantities per acre. Probably all his
fields need the full action of the organic matter in its rotting. The
percentage of humus-making material is low. The place for fresh manure
is on the land, when this is feasible. The covered shed is a device for
holding manure with least possible loss when spreading cannot be done,
or a supply must be carried over for land in the summer. The gain in
condition is only incidental, and an advantage chiefly to vegetables.
The composting of manure by gardeners is not a practice to be copied on
most farms.
Poultry Manure.--The value of poultry manure often is overestimated.
Its content of plant-food is one half greater than that of horse
manure, ton for ton. The availability of the nitrogen is so great that
returns from applications are immediate, and give the impression of
greater strength than is possessed. Its availability makes it excellent
for plants that need forcing. For such use it needs reenforcing only
with acid phosphate, but as a general manure it should have the
addition of potash. Acid phosphate should be used in the poultry-house
to prevent loss of nitrogen, which escapes quickly on account of rapid
fermentation, and to supply phosphoric acid. Thirty pounds of acid
phosphate to each 100 pounds of the manure gives a mixture containing
one pound of nitrogen, three pounds of phosphoric acid, and two fifths
of a pound of potash. The addition of four pounds of muriate of potash
makes the mixture a well-balanced and effective fertilizer when used at
the rate of 500 to 1000 pounds per acre. Dry muck or loam should be
mixed with it to serve as an absorbent and to give good physical
condition.
CHAPTER XIV
THE USE OF STABLE MANURE
Controlling Factors.--The farm supply of stable manure is a carrier of
plant-food, returning to the soil four fifths of all the fertility
removed in the crops fed, but it is much more than this. Land which
receives only plant-food, as may be the case when fertility is supplied
in commercial fertilizers, loses good physical condition. Organic
matter is needed for maintenance of physical condition, the retention
of soil moisture, the freeing of inert minerals in the land, and the
promotion of bacterial life in the soil. No small share of the value of
a ton of manure is due to its organic matter. This is a factor in the
problem when deciding what disposition of the manure will pay best. One
field may be in condition to respond fully to the use of commercial
fertilizers, while another is too deficient in humus for best results.
Some crops are more insistent upon supplies of organic matter than
others.
Again, the disposition of the manure depends upon the supply. If most
crops are fed on the farm, the manure is a leading source of fertility
for all fields and crops, and may be used once or twice in the
crop-rotation on every field. If the manure is in small amount, due to
a scheme of farming involving the growing of crops for market, the
function of the manure may be only to encourage the starting of sods,
in which legumes are a leading factor.
Direct Use for Corn.--The practice of spreading manure on grass land
for corn is based upon much good experience. The custom is nearly
universal in regions where corn is an important part of a four, five,
or six years' rotation, and all of the corn and hay is fed on the farm.
This disposition of the manure permits the handling at times when other
work does not rush. The supply carried over from the spring is put on
in late summer, and the manure made in the early part of the winter can
be drawn to the field fast as made. Manure spread immediately before
the sod is broken is less effective, as no leaching of soluble elements
into the surface soil occurs before the coarse material is buried in
the bottom of the furrow.
[Illustration: Corn in the Ohio Valley.]
The use of fresh manures for corn is rational, because corn is a gross
feeder and requires much nitrogen. All plants having heavy foliage can
use nitrogen in large amounts. It is possible to apply manure in
excessive amount for this cereal, the growth of stalk becoming out of
proportion to the ear, but the instances are relatively few. Ordinarily
corn suffers from lack of nitrogen. When the farm manure is in large
amount, its direct use for corn is good practice.
Effect upon Moisture.--Coarse manures should not be plowed down late in
the spring, as they increase the ill effects of drouth. Decayed
vegetation, well mixed with the soil, increases the soil's
water-holding capacity, but undecayed material in the bottom of the
furrow is harmful. Fresh, strawy manure, made immediately before the
time for breaking a sod, is preferably carried over in a covered shed
until a later season of the year.
When manure has been spread upon a sod in the fall or early winter, it
decays quickly after the plowing, and aids in resistance to drouth.
When it is plowed down, the ground is kept more porous, and the
presence of plant-food and moisture at or near the depth of plowing
encourages deeper rooting of plants, and thus indirectly assists them
to withstand dry weather. If the plowing is good in character, leaving
the furrow-slice partly on edge, and permitting the harrow to mix part
of the turf and the manure with the remainder of the soil, the best
conditions respecting moisture are secured.
Manure on Grass.--When the crop-rotation embraces two or more years of
grass, or one of clover followed by only one of grass, it is better
practice to use the manure to thicken the sod. The object in view is
the largest possible amount of crops, and the maximum amount of organic
matter for the soil. Grass is a heavy feeder, like corn, and makes good
use of nitrogen. Its roots fill the soil so that no loss attends the
use of manure. When the supply is given the grass, after the harvest of
the second crop of clover and during the winter, the timothy can make a
rank growth. The part of the plant above ground has corresponding
development below ground. Not only does a large increase in the hay
crop result, but the heavy mass of grass roots, the aftermath, and the
remains of the manure provide a great amount of fertility for the corn
which follows. The increase in hay permits a corresponding increase in
the manure supply the next year, if it is fed, and if it is sold on
account of a market price greater than its value for feed and manure,
it adds to income materially--and that is one reason for farming.
Manure on Potatoes.--There are excellent cash crops that may get more
than their fair share of the farm supply of fertility, and against the
interest of fields in the farm not adapted to cash crops. The
justification is found in the farm ledger. In some regions potatoes are
the best crop in point of net income per acre, where the acreage is
kept restricted so that there may be plenty of organic matter to help
in conserving moisture. It is not good practice to use fresh manure,
and especially that from horse-stables, for potatoes. A heavy
application makes an excessive growth of vine, and the yield of tubers
suffers. A stronger deterrent is the effect that fresh manure has on
the development of the spores that produce the disease known as
potato-scab. Rotted manure is less dangerous, and few crops repay its
use in higher degree than the potato. Some growers prefer to make heavy
application of fresh manure to grass for corn, and follow with potatoes
so that they can profit by the rotted organic matter that remains. In
this way the physical condition is made excellent, moisture is well
held in a dry season, and commercial fertilizers can supplement the
plant-food left in the manure.
When to plow Down.--Excellent farmers differ regarding the relative
efficiencies of manure plowed down and that mixed with the top soil.
Both classes may be right for their individual instances. The plowing
down of manure helps to deepen the soil, and that always is desirable.
It causes plants to root deeply, and that is a distinct benefit in a
drouthy season, and always desirable. When a soil is in such tilth that
the breaking-plow always brings fertile soil to the surface, the
plowing down of manure gives excellent results, though it should be
permitted to leach at the surface for a few weeks before being turned
under. When land is being prepared for a seeding to grass or clover,
the supply of manure should not be plowed down wherever the
breaking-plow brings soil to the surface that is deficient in humus. In
the latter case the manure always should be used as a top-dressing, and
should be evenly spread and well mixed with the surface soil. It is
needed there far more than it can be needed farther down. The surface
soil always should have a high content of organic matter.
Heavy Applications.--When the farm supply of manure is small,
applications should be light. The manure should not be the dependence
for plant-food on a part of a field, or a single field of the farm,
under such circumstances. It is more profitable to give a light
dressing to a larger area. The manure is needed to make a fertilizing
crop grow, and a very few tons per acre can assist greatly, when
rightly used. The manure is needed to furnish bacteria to the soil, and
a small amount per acre is useful for this purpose. Always there is
temptation to use all the manure on a field convenient to the barn, and
to concentrate it on a sufficiently small area to make a good yield
sure. The loss to the farm in this method is heavy. The thin spots and
the thin fields have first right to the manure as a top-dressing, and
six tons per acre will bring larger returns per ton than twelve tons
per acre. At the Pennsylvania experiment station the land receiving ten
tons of manure per acre in the common four years' rotation of corn,
oats, wheat, and mixed clover and grass gives added returns of $1.63 a
ton, while an application of eight tons pays $1.85 a ton, and a six-ton
application brings the value per ton up to $2.41. These applications
are made twice in the four years.
Reenforcement with Minerals.--A ton of mixed manure in the stable
contains about ten pounds of nitrogen, five pounds of phosphoric acid,
and ten pounds of potash. This makes the percentage of nitrogen and
potash the same, while the percentage of phosphoric acid is only half
as high. A commercial fertilizer of such percentages would be esteemed
a badly balanced one. Certainly the phosphoric acid should be
relatively high, as this constituent of plant-food runs low in the
soil. If 50 pounds of 14 per cent acid phosphate were added to each ton
of manure while it is being made in the stable, seven pounds of
phosphoric acid would be added, making the percentage in the manure a
little higher than that of the nitrogen and the potash. A better
balance is given to the fertility. There cannot be any loss in this
purchased plant-food, if the stable floor is tight. Fermentation cannot
drive it off, and when applied to the soil it is tightly held.
Practically no phosphoric acid is found in drainage waters. Eight tons
of manure thus reenforced would contain the same amount of plant-food
as a ton of fertilizer having 4 per cent nitrogen, 5 per cent
phosphoric acid, and 4 per cent potash. The addition of the 50 pounds
of acid phosphate per ton does not bring the phosphoric acid content up
as high relatively as in most commercial fertilizers, but it helps. The
total amount in the eight tons manure may be sufficient, and the
greater part of the total has sufficiently immediate availability,
while the manure must undergo decomposition, and some of the nitrogen
and potash does not become available within the year.
Durability of Manure.--Tests of the durability of manure in the soil
involve some uncertain factors, but we are interested only in the
effects of applications. These effects may continue for a long term of
years, and an example will illustrate. Land may be too infertile to
make a good clover sod. If a good dressing of manure be given half the
land, affording proper conditions for making a sod, the result will be
a heavy growth of clover, while the seeding on the unmanured half will
be nearly a failure. If no manure or fertilizer be used in the
crop-rotation, the probability is the manured portion of the field will
again make a fairly good sod. How much this success may be due to the
remains of the manure, and how much is attributable to the effect of
the clover and to better bacterial life introduced and favored by the
manure, no one knows. Probably the greater part of the benefit comes
only indirectly from the manure applied three or four years previously.
Half of the field may thus be lifted out of a helpless state and remain
out of it for a long term of years, while the other half grows only
poorer. A probable illustration of this lasting indirect effect may be
seen in one of the plats in the soil fertility experiments on the
Pennsylvania experiment station farm.
Experiments at the Rothamstead station, England, show some lasting
results from applications of manure. Director Hall cites the case of
one plat of grass land which was highly manured each year from 1856 to
1863, and has since been left unmanured. In 1864 this plat gave double
the yield of an adjoining plat which had been left unmanured during the
eight years. In 1865 the plat, last manured in 1863, gave over double
the yield of the unmanured. In the following ten years its yield was a
half more than that of the unmanured. In the next ten years the yield
was a quarter more. In the next ten years it fell to 6 per cent more
than the plat that had received no manure in the beginning of the
experiment. In the following ten years it rose to 15 per cent. Here is
a lasting effect of manure for over forty years where grass was grown
continuously.
CHAPTER XV
CROP-ROTATIONS
The Farm Scheme.--Notwithstanding some of the theorizing that does not
commend itself to the practical man, farm management is taking on the
form of a science. It involves the organization of a farm for best
results, and in the scheme that should be worked out for any particular
farm the most important feature is the crop-rotation. The selection of
crops is controlled by so many local considerations, including the
personal likes and dislikes of the farmer, that very rightly the kinds
of rotation are innumerable. The order in which crops may be grown with
most profit is less variable, and yet even here local conditions may
quickly derange the scheme of a theorist. There is, however, such right
relation of facts to each other that we are getting a working
philosophy, and the individual farmer can bend practice to his own
liking in considerable degree, and yet not compel plants to do their
part at a disadvantage. He has much liberty in the order of their
growing, without endangering profits materially. Theoretically, this is
not true, and the factors of production on any farm are such that the
largest return is obtainable in only one scheme of farming. Practically
there is rather wide liberty.
Value of Rotation.--Experience has shown the benefit of variety in
crops grown on land. Among the advantages of crop-rotation are the
following:
1. It enables the farmer to maintain the supply of organic matter
in his soil. The roots and stubble of a grain crop are insufficient
for this purpose, and the introduction of a sod or cover crop is
helpful.
2. It permits the use of legumes to secure cheap supplies of
nitrogen.
3. Some plants feed near the surface of the ground, and the use of
other plants which send roots deeper adds to the production.
4. Some crops leave the soil in bad physical condition, and the use
of other crops in the rotation serves as a corrective.
5. The keeping of livestock is made more feasible and profitable,
and this leads to increase in farm manures.
6. In a proper succession of crops the soil is covered with living
plants nearly all the time, and thus is prevented from washing or
leaching.
7. In addition to these influences upon soil fertility, crop-rotation
assists in control of insect and fungous foes and of weeds; it
permits such distribution of labor on the farm that the largest
total production may be secured by its employment; and it saves the
farmer from sole dependence upon a single crop.
[Illustration: Penn's Valley, Pennsylvania.]
Selection of Crops.--The natural inclination of the farmer is a
consideration that cannot be ignored. If a man does not like certain
kinds of animals or crops, his farm or market must possess an unusual
advantage to counter-balance. Illustration of this truth may be seen in
every farming community.
As a rule, the crops should be those that are well adapted to the
particular soils upon which they are grown. It is up-hill work to
compete with producers whose soils have far better adaptation, unless
the local markets equalize conditions.
The crops should follow each other in such succession that each crop
naturally paves the way for the next one in the succession, or at least
does not place its successor at a disadvantage.
When it is feasible, a rather large proportion of the entire produce of
the rotation should be feeding-stuff for livestock, as soil fertility
is most easily guarded by livestock farming. This is desirable when
consistent with profit, but, as we have seen, it is not an absolute
essential.
An Old Succession of Crops.--In the corn belt of the northern states
some time-honored crop-rotations have been formed by corn, oats, wheat,
clover, and timothy. The number of years devoted to the grain and to
the sod has varied with the soil and the desire of its owner. A common
succession is corn one year, oats one year, wheat one year, clover and
timothy one year, timothy one year--a five years' rotation that has
much substantial success behind it. Such a rotation is wholly
reasonable and in accord with the nature of things. Every year
furnishes some organic matter for the soil in roots and stubble, and
all the produce of four years out of the five may be fed on the farm.
There is one cash crop, or two if the price of the clear timothy hay
justifies sale.
The manure may be hauled upon the sod when other work does not press,
and it goes where the crop is one that prefers fresh manure, be that
the grass or the corn. There is plenty of time after the corn to
prepare for oats, and after the oats to prepare for wheat. The
preparation for the wheat is sufficient for the clover and timothy. The
seedings come only in the spring and the fall, when rainfall is more
abundant and effective than in mid-summer. The danger of failure in
case of this rotation is relatively small.
Corn Two Years.--Hunt says that the prosperity of the east, as a whole,
would be greatly increased if the rotations of crops were so modified
as to increase the corn acreage. He suggests the four rotations given
in the table below, which is taken from Bulletin 116 of the
Pennsylvania experiment station. The fertilizers recommended should
maintain fertility.
CORN IN CROP-ROTATIONS
+-------+-------+-------+-------+-------------------------------------+
| 3 Yr. | 4 Yr. | 5 Yr. | 7 Yr. | |
| ------+-------+-------+-------+-------------------------------------+
| | | | 1 | Corn: 6 to 10 loads of manure and 25|
| | | | | pounds of phosphoric acid. |
| 1 | 1 | 1 | 2 | Corn: 6 to 10 loads of manure and 25|
| | | | | pounds of phosphoric acid. |
| | 2 | 2 | 3 | Oats: no fertilizer. |
| 2 | 3 | 3 | 4 | Wheat: 50 pounds each of phosphoric |
| | | | | acid and potash. |
| 3 | 4 | 4 | 5 | Clover and timothy: no fertilizer. |
| | | 5 | 6 | Timothy: 25 pounds each of nitrogen,|
| | | | | phosphoric acid, and potash. |
| | | | 7 | Timothy: 25 pounds each of nitrogen,|
| | | | | phosphoric acid, and potash. |
+-------+-------+-------+-------+-------------------------------------+
The Oat Crop.--In the northern part of the corn belt the oat crop is
profitable. In the southern half of Ohio and regions of like temperature
the oat crop rarely pays. The heat, when the oat is in the milk stage,
usually is too great. The tendency there is to eliminate this crop.
Where silage is wanted, the stubble-land can be seeded directly to
wheat with good results. A common practice is to seed to wheat between
the shocked corn, and the wheat does poorly unless the soil is quite
fertile.
Two Crops of Wheat.--A common practice has been to grow two crops of
wheat, seeding first in the corn stubble-land, and plowing the ground
for the second wheat crop, making a smooth surface for mowing. This
method ceased to pay well when wheat became low in price. It has the
advantage of giving two cash crops to the rotation.
Where winter wheat does not thrive in the north, it is dropped out, and
the seeding to clover and grass is with the oat crop. There is the
compensation of a large oat yield where the climate is too cold for a
good crop of wheat.
[Illustration: In the Shenandoah Valley.]
The Clover and Timothy.--The timothy and clover sod is made
inexpensively so far as labor is concerned. The first crop of hay is
chiefly clover, and the soil is enriched by the roots and stubble,
while the hay is converted into manure.
The second year the hay is nearly clear timothy. The sod should not be
left until it becomes thin, but should be turned under while heavy, no
matter if this must be after one season's harvest, or two. A sod stands
three or four years for harvest on some farms, and without heavy
fertilization there is decrease in fertility.
Two Legumes in the Rotation.--If all the crops of this five years'
rotation, excepting wheat, were fed on the farm, and if all the manure
were saved and rightly applied, there would be little or no difficulty
in maintaining fertility, provided the soil were friendly to clover.
The fact is that much such land has grown poorer, and it is known that
another legume is needed in the rotation. The substitution of the
soybean or cowpea for the oat crop gives excellent results. It makes a
large supply of rich hay, and it fits the soil nicely for winter grain.
The use of the breaking-plow is escaped. The surface of the land is in
good tilth, especially if the legume was planted in rows so that
cultivation could be given. A cutaway harrow, run shallow, and a roller
make the seed-bed. Near the southern edge of the oat belt this
substitution gives more value in the crop following corn, and at the
same time conserves soil fertility.
Where land is thin, a four years' rotation of corn, soybeans or
cowpeas, wheat, and clover is one of the best, because it contains two
leguminous crops, and because one of them favors the wheat which
follows and the clover seeded in the wheat.
Potatoes after Corn.--When potatoes are grown in the corn belt, a five
years' rotation of corn, potatoes, oats, wheat, and clover, or corn,
potatoes, wheat, clover, and timothy, is one of the best. When a late
potato crop is grown, there is not time for seeding to wheat in cool
latitudes, and the oat crop, or the soybean, fits in best. Farther
south, where the oat crop is less profitable, there usually is time to
go directly to wheat.
The advantage in this rotation is that the fresh manure can be used on
the sod for the corn, and the potato thrives in the rotted remains of
the sod and manure. Corn leaves the soil in good physical condition for
the potato. Co
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