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SOILS AND PLANT LIFE AS RELATED
TO AGRICULTURE
THE MACMILLAN COMPANY
NEW YORK - BOSTON - CHICAGO + DALLAS
ATLANTA + SAN FRANCISCO
MACMILLAN & CO., LimiTEp
LONDON + BOMBAY + CALCUTTA
MELBOURNE
THE MACMILLAN CO. OF CANADA, Ltp.
TORONTO
A PRiIzE-WINNING BUSHEL
SOILS AND PLANT LIFE
AS
RELATED TO AGRICULTURE
BY
J. C. CUNNINGHAM
PROFESSOR OF HORTICULTURE AND BOTANY IN TWO-YEAR COURSE IN AGRICULTURE
AND TEACHER OF AGRICULTURE TO RURAL AND GRADE TEACHERS
IOWA STATE COLLEGE, AMES, IOWA
AND
Wet. LANCELOT
INSTRUCTOR IN CHEMISTRY, TWO-YEAR COURSE IN AGRICULTURE
IOWA STATE COLLEGE
Nets Bork
THE MACMILLAN COMPANY
1915
All rights reserved
CopyrigutT, 1915,
By THE MACMILLAN COMPANY.
Set up and electrotyped. Published August, 1915.
Norwood Jress
J. 8. Cushing Co. — Berwick & Smith Co.
Norwood, Mass., U.S.A.
AUG 26 Igo
©clA410231
Wad 9,
PREFACE
Tus publication represents a desire on the part of the
senior author to present a first study in agriculture for rural,
grade, and high schools, based upon sound educational
principles.
An enumeration of a few of these principles will serve as
a key to the plan of the book:
1. Pupils must be led by easy steps from the known to
the unknown.
2. One thing at a time must be taught and this one thing
must be thoroughly understood.
3. Real progress in education depends upon a pupil’s
ability to discern agreements and differences.
4. A teacher should stimulate and direct, but all educa-
tion comes from the pupil’s voluntary effort.
Our purpose in the pages that follow is to stimulate and
direct the pupils in such a manner that they will proceed by
“easy steps from the known to the unknown” and that
their mental powers will be developed by their own volun-
tary efforts.
If this book is to be merely one from which a certain
number of pages are assigned to-day to be recited in a
parrot-like manner to-morrow, it must prove a complete
failure.
If the exercises are performed as the authors have in-
tended, a few — and only a few — set rules will be observed:
First. — The pupil must wnderstand clearly before begin-
ning just what he is setting out to do.
Second. — He should follow the directions carefully.
Third. — In his conclusion, he should be expected not
a
vi PREFACE
only to show a clear discernment of “agreements and dif-
ferences” but to state them clearly in his notebook.
The exercises which are here presented can not be per-
formed in all schools by each pupil. The work can easily
be completed, however, by assigning one exercise to a cer-
tain pupil or group of pupils, the next to another individual
“or group, and so on. The exercises may be worked out
either in the schoolroom or at home, according to the judg-
ment of the teacher. There is no better training for a pupil
than that of presenting before a class the facts he has found
out for himself.
In the back of the book will be found a list of materials
which should be gathered together and stored in some sort
of box before school opens. Better still, a cabinet may be
made, or secured, in which the materials can be compactly
stored. This will save space, which is always at a premium
in the schoolroom. All pieces of apparatus should be
washed clean, wiped dry, and put back in their places as
soon as the work is completed. This will save the teacher
much trouble, while it will at the same time tend to teach
the pupils neatness and order.
Each pupil should have a durably bound notebook of
specified size, a drawing pencil, and a small hand lens.
In addition to a box for the storage of equipment, another
should be provided in which a few plants or other perish- .
able articles may be protected from freezing. Ordinarily,
it simplifies the work to have some person in the commu-
nity grow the potted plants which require care and attention
in order that they may develop properly.
The material in this book is presented as a first study in
agriculture. It deals alone with soils and plants, for we
think that agricultural subjects can best be divided into plant
studies and animal studies. The latter should be presented
as a second, or advanced year’s work.
It must not be understood that the chapters in this book
PREFACE Vil
are necessarily to be followed in the order given. On the
other hand, any combination of chapters which is best fitted
to the season may be adopted. For instance, when school
opens in the fall, flowers and seeds can be easily obtained.
Chapter XII will make an excellent starting point at this
time. Then may follow Chapters XIII and VII, after
which one may turn back to the beginning of the book and
proceed in regular order, reviewing or omitting the chapters
already studied. Exercise 36, however, should be started
in the late fall, regardless of the order that 1s followed in
the book.
Teaching agriculture is a delightful task, provided we do
not attempt to tell “how to farm.” All we should attempt
to do is to stimulate and direct the pupil in his desire to
find out the fundamental principles of good farming.
It is our privilege to unify or to “make one” the school
work and the common experiences and practices of the farm
to the end that life in the open country may be richer and
fuller for all of us who dwell there.
In the preparation of this work, the senior author has
been ably assisted by W. H. Lancelot, a man of wide expe-
rience both in educational and in editorial work.
Recognition is also due to Mr. Willard Zeller, a highly
successful corn grower and breeder of Cooper, Iowa, who
reviewed the chapter on corn.
H. L. Eichling, Associate Professor of Agronomy, and
teacher of agriculture for rural and grade teachers in the
summer school of Iowa State College, has carefully reviewed
the chapters on soils and farm crops and has offered very
many helpful suggestions.
I desire to express my appreciation of this valuable
assistance.
J. C. CUNNINGHAM.
AmEs, Iowa,
June 1, 1915.
A LETTER TO THE STUDENT
NEARLY sixty years ago a lad ten or twelve years of age
gathered together in his father’s cellar a collection of bot-
tles, jars, chemicals, and other equipment. He had gone to
school but three months in his life. Yet with the help of
his mother, he read the best books she could secure. He
obtained a copy of Parker’s School Philosophy and worked
out in his “den” in the cellar almost every experiment in
the book. Moreover, he tested to his satisfaction many of
the statements he encountered in his reading. |
People would have smiled if, fifty years ago, any one had
said of this lad of Port Huron, Michigan: “ He will make the
streets of your cities at night as light as day. He will
reproduce music and the human voice on cylinders of wax.
He will make it possible for every village to have a moving
picture show. He will use electricity instead of horses to
propel your street cars.” Yet Thomas Alva Edison has
brought these very things and more to pass. He laid the
foundation for these great inventions by working out for
himself the statements he found in his books.
The boy on the following page holds in his hands a rock
and a bit of soil. He has been told that soil comes from
rocks ; that plants draw their nourishment from the soil and
the air; that when they die, they also become a part of the
soil. On the pages that follow are found brief directions
for learning some of the truths about the soil and plants.
Let us together perform the experiments. Very few, or
ix
xX A LETTER TO THE STUDENT
perhaps none of us, will become great inventors like
Mr. Edison; yet we can open a storehouse, filled with
Boy with a rock anda bit of soil.
wonderful treasures of knowledge about the plants, the
animals, and the soil that we see every day.
Great buildings are constructed by laying stone upon
stone. Real knowledge is gained by proving one truth after
another.
The first question to ask is, “ What is my object, or what
do I wish to find out?”
A LETTER TO THE STUDENT Xl
The second step is procedure: “ How shall I go about it
to find out ? ”
The third is the conclusion: “ What have I found out, or
proved ? ”
We should keep a notebook, in which to make a neat,
eareful record of the experiments we perform. Here is an
illustration from a student’s notebook, which shows about
how the exercises which follow should be recorded :
EXERCISE 9
Object.— To learn what effect plowimg under a heavy
crop of straw has upon the rise of water in the soil.
Procedure. —1 stretched a piece of cheesecloth across the
bottom of a lamp chimney and tied it firmly in place.
Then I filled the chimney two thirds full of fine soil, added
one half inch of finely chopped straw, and added fine soil
again until the chimney was full. I put the lower end of
the chimney into a pan of water, and watched the moisture
rise through the soil.
I filled another chimney exactly as I had filled the first,
except that I left out the layer of straw. I put the lower
end of this chimney into the water and watched the mois-
ture rise through the soil.
Conclusion. — The water was drawn up through the soil
just as a lamp wick draws up the oil. In the first chimney,
the water rose as far as the straw, and there it stopped.
In the second chimney, it rose to the surface of the soil.
This must mean, then, that when any thing like a layer of
straw or weeds or perhaps even clods is plowed under, the
“wicks ” or tubes in the soil are broken. In this case, the
moisture could not rise to the roots of the young plants,
and they would be injured and perhaps die unless there was
plenty of rain.
Exercises, such as this, will very often lead to a desire on
your part to perform the same work on a larger scale in the
Xl A LETTER TO THE STUDENT
field. The general procedure, however, should be the same.
Know your object, or what you wish to find out; proceed
by securing a plot of ground and following carefully the plan,
which is to test your theories ; and finally, think over your
results very carefully, turning them over and over in your
mind, as we say, so that you may not finally reach a conclu-
sion that is untrue, or one that is only partly true.
Winners of a corn growing contest.
A great many people will be interested in your conclu-
sions, especially if they prove to be accurate and true, for
the principal way of securing the much needed increase in
our crop yields is not to farm more land, since the best of it
is now under the plow, but to increase the yield per acre of
that which we are now farming.
J. C. CUNNINGHAM.
W. H. LANCELOT.
CONTENTS
- PREFACE : : i ; s : . ‘
A LETTER TO THE STUDENT.
SOILS
CHAPTER I
How Soits arE Mape anp MIxep ; ‘ .
What the Soil is, 1 — Grinding up the Rocks, 1 — Soil
Names, or Types, 4— Two Sources of Soil Material, 5 —
The Part Plant Life plays in making Soils, 7 — The Part
Animal Life plays in making and mixing Soils, 8 — Ele-
ments in the Soil and Air which Plants must have in
Order to make a Healthy Growth, 10.
CHAPTER II
THE WATER IN THE SOIL
How the Soil loses Water, 13—The Water which
runs off the Surface, 13—The Water which filters down
through the Soil and drains away, 16 — How Water en-
ters Drain Tile, 18 —'Three Kinds of Water in the Soil,
19— How Film Moisture works its Way upward in the
Soil, 21 — How the Farmer prevents the Escape of Film
Moisture, 23.
CHAPTER III
THE AIR IN THE Soi. .
Why Air is necessary in the Soil, 25—— Why we seek
to control the Air Space in the Soil, 25— How we may
get More Air into the Soil, 28.
xiii
PAGES
v-vii
xxii
13-24
25-29
X1V CONTENTS
CHAPTER IV
PAGES
THe TEMPERATURE OF THE SOIL. : ‘ : : . 30-85
Proper Temperature Necessary for Germination, 30
How Temperature of the Soil is governed, 80 — How the
Air Space in a Soil affects its Temperature, 31— How
the Moisture in a Soil affects its Temperature, 58 — How
the Color of a Soil affects its Temperature, 34— The
Advantages of a Warm Soil, 34.
CHAPTER V 5
THE TILLAGE OF SOILS : ; : : : ; : 36-43
Why we till the Soil, 36 — Improving the Texture and
Structure of the Soil, 86 — One Cause of Cloddy Fields,
39 — Covering, or Working into the Soil, Organic Mat-
ter, 40 — Putting Seed into the Seed Bed, 40 — Destroy-
ing Weeds, 41— Forming a Dust Mulch, 42— Making
it Possible for Air and Water to enter the Soil, 42.
PLANT LIFE
CHAPTER VI
THE Rounp oF PuLant LIFE : : : : ‘ ; 44-45
The Life Cycle of Plants, 44— How the Parts of a
Plant work together, 44.
CHAPTER VII
THE SEED: Irs SELECTION AND DisTRIBUTION . : ; 46-61
The Functions of the Seed, 46 — How the Embryo is
protected, 46 — How Seeds are scattered by, Nature, 46
— How Seeds are scattered by Man, 49— Making a
Seed Collection, 50 — How Nature selects Seeds, 52 —
How Man selects Seeds, 52— Selecting Specimens for
Corn Judging, 56 — Nature stores No Seeds but provides
for Loss, 57 — Man’s Storage of Seeds, 58.
CONTENTS XV
CHAPTER VIII
PAGES
SEED GERMINATION ‘ ; 62-76
What a Seed is, er Great Classes of ‘Plants, 62
— The Conditions required for Seed Germination, 64 —
Moisture and Germination, 65 — Temperature and Ger-
mination, 67— Changes which take place within the
Germinating Seed, 68 — Heat generated during Germi-
nation, 71 — How Size of Seed affects Growth of Young
Plant, 73 — Direction of Growth, 74— The Embryo be-
comes a Seedling, 75.
CHAPTER IX
Tue Work or Roots . ; . : 77-88
What Roots do, 77 — Gathering Food and Meee
77— Roots are able to select the Minerals which they
need, 79—The Origin of Roots, 80— How Roots work
their Way through the Soil, 81— The Extent and Depth
of Roots, 82 — How Roots help dissolve Mineral Matter,
84— How Roots hold Plants Erect, 85—The Root a
Storehouse of Food, 87 — Benefits of Roots, 88.
CHAPTER X
THE Work OF LEAVES : : : : ; ; : 89-97
Functions and Uses of Leaves, 89 — The Manufacture
of Starch, 89— The Green Leaf likened to a Mill, 90 —
How Other Foods are made, 91— Amount of Water,
Food Material, and Ash in Plants, 92—The Water
given off by Leaves, 93 — Storage of Food in the
Leaves, 96.
CHAPTER XI
THe WorK OF STEMS . : : : : ; 5 . 98-106
The Functions of Stems, 98 — The Forms of Stems,
98 — Prostrate Stems, 98 — Climbing Stems, 99 — Erect
Stems, 99 — Study of the Forms of Stems, 100— How
Water travels from Roots to Leaves, 101 — How to tell
the Age of a Tree, 102 — How Food travels from Leaves
Xvl CONTENTS
PAGES
to Roots, 1083 — The Flow of Sap, 104—The Cambium
Layer, 104 — Rope, Twine and Linen Material, 105.
CHAPTER XII
Tose Work OF FLOWERS : 107-116
The Work in which All Parts join, 107 — What the
Flower does, 107— Parts of the Flower on Separate
Plants or on Different Parts of the Same Plant, 110—
How the Pollen gets from one Plant to another, 110 —
The Flowers which depend upon Insects to carry Pollen,
111— The Flowers which depend upon Wind to carry
Pollen, 111— What happens after the Pollen reaches
the Stigma, 112 — Cross-fertilization the Rule, 113—
Cross-fertilization by Hand, 118.
CHAPTER XU
THe FORMATION AND DEVELOPMENT OF SEED . ; . 117-21
How the Food is stored in the Seed, 117 — How Man
may thwart Nature’s Plan, 118— The Forms and Uses
of the Various Food Materials in the Seed, 120.
CHAPTER X1Ty.
THE PROPAGATION OF PLANTS : : 3 , 122-144
How Plants are Propagated, 122 — pronadiaited by
Spores, 124—- How Spores are Spread, 127 — How to
prevent the Spread and Growth of the Spores of Disease,
128 — Conditions which favor the Entrance and Growth
of Spores, 133— Propagation by Seed, 1338 — Propaga-
tion by some Part of the Plant other than Seed or
Spore, 184— Plants formed while still attached to the
Parent Plant, 134— Plants formed by Portions which
become detached from Parent Plant, 136 — Plants formed
by the Union of Two Plants, 138.
CHAPTER “Av
Way Man CuttivaTEs PLANTS . : F é ‘ . 145-148
Classes of Plants according to the Parts for which
they are cultivated, 145.
CONTENTS XVI
CHAPTER XVI
PAGES
Corn : : : ; : 149-202
Uses of Corn, 149 — Distribution of Corn, 150 — How
the Corn Plant has changed as it has moved Northward,
151 — Climatic Requirements of the Corn Plant, 152 —
Soil Requirements of the Corn Plant, 154— The Pro-
duction of Corn, 154 — Selection of the Seed, 154 —The
Selection of the Seed Supply, 169— How Selection of
Seed may influence the Yield, 172 — Drying out the
Seed, 172 —Storing the Seed, 173 — Testing the Seed,
174 — Grading the Seed, 179— The Ideal Seed Bed for
Corn, 181 — Preparing a Seed Bed in Sod Ground, 182
— Preparing a Seed Bed in Cornstalk Ground, 184 —
Preparing a Seed Bed in Stubble Ground, 185 — Plant-
ing the Seed, 185— The Time of Planting, 187 —The
Depth of Planting, 188 — Distance between the Rows,
189 — The Number of Kernels in Each Hill, 189 — The
Replanting of the Missing Hilis, 190 — Cultivation be-
gins with the Harrow, 191 — Later Cultivation of the
Crop, 191— Depth of Cultivation, 193— Frequency of
Cultivation, 194— Cultivation of Listed Corn, 195 —
Harvesting the Crop, 196 —Crops used as Substitutes
for Corn, 198— Planting and cultivating Kafir Corn
and Similar Drouth-resistant Crops, 200.
CHAPTER XVII
THE SMALL GRAINS ; 4 ; : : : , eee
Why Wheat is so extensively grown, 203 — Climatic
Conditions Favorable for the Growth of Wheat, 205 —
Winter and Spring Wheat, 205 — Systems of Rotation,
205 — The Seed Bed and how to prepare it, 206 — Selec-
tion of the Seed, 207 — Planting the Seed, 210 — Har-
‘vesting the Wheat, 211— The Uses of Wheat, 212 —
Oats a Cool Climate Crop, 213 — Varieties of Oats, 214
— Preparation of the Seed Bed, 215— The Selection of
Oats for Seed, 216 — Harvesting the Crop, 218 — Shock-
ing and Stacking Oats, 218 — The Uses of Oats, 219 —
Oatmeal, 219 — Methods of Cultivation and Uses of Bar-
ley, 221—Soil Requirements and Uses of Rye, 221 —
XVIll CONTENTS
PAGES
The Soil Requirements of Rice, 222 — Preparation of the
Seed Bed, 222 — Planting the Seed, 223 — Caring for the
Growing Crop, 223 — How the Grain is prepared for Use,
223 — Uses of Rice, 224.
CHAPTER XVIII
GRASSES FOR PASTURES, MEADOWS AND LAwNSs . . . 225-237
Characteristics of all the Grasses, 225— A Peculiar
Habit of Growth, 226 — Wild Grasses, 227 — Cultivated
Grasses, 227 — Where and how Timothy is grown, 227 —
Advantages and Disadvantages of Timothy, 228 — When
to cut Timothy, 229 — The Character and Value of Blue
Grass, 230— The Seeding of Blue Grass, 231 — Advan-
tages and Disadvantages of Blue Grass, 252 — The Range
and Character of Redtop, 232 — Its Advantages and Dis-
advantages, 233 —The Range and Character of Bermuda
Grass, 234 — Advantages and Disadvantages of Bermuda
Grass, 2834—-Where each Grass thrives, 2386— Why
Clovers should be grown with Grasses, 256.
CHAPTER XIX
CLOVERS AND OTHER LEGUMES . : j ; : . 2ooaaie
Characteristics of the Legumes, 258 — How Legumes
benefit the Farmer, 239 — How Legumes add Nitrogen
to the Soil, 240 — How Roots of Legumes open the Soil,
241 — How Legumes add Humus to the Soil, 241 — How
Legumes make other Plant Food Available, 241 — How
Legumes balance the Food Ration, 242 — How Legumes
assist in the Control of Insects and Fungous Pests, 242 —
Where the Different Legumes grow, 242 — Why Clovers
frequently fail, 250 — How Acid Soil affects Clovers, 252
— How a Lack of Phosphorus affects Clovers, 254—_
How a Lack of Humus affects Clovers, 255 — How Ab-
sence of Friendly Bacteria affects the Clovers, 255 —
How the Nurse Crop may affect Clovers, 256 — How the
Method of Seeding may affect Clovers, 256 — How Drouth
may affect Young Clovers, 257 — How to succeed with
Clovers, 258 — How to correct an Acid Soil, 258 — How
CONTENTS X1X
PAGES
to add Humus and Phosphorus to the Soil, 259— How
Bacteria are added to the Soil, 259 — The most Suitable
Nurse Crops for Clovers, 260 — How the Seed should be
planted, 261 — Seed Selection and Analysis, 261 — Table
of Weed Seed Weights, 265 — Methods of Culture of the
Legumes, 266 — Securing the Maximum Benefits from
Legumes, 272.
CHAPTER XX
THe Fiser Crops : : ‘ 5 5 . 274-286
Three Crops yielding Valuable Fibers, 274 — Valuable
Products Other than Fiber, 274— The Importance of
Cotton, 275 — Where Cotton is grown in the United
States, 275 — The Cotton Plant, 276 — Growing the Cot-
ton Crop, 277 — Harvesting the Crop, 280 — Ginning the
Cotton, 280 — Proportion and Value of Seed and Lint,
281 — How and where Flax is Grown, 282 — Methods of
Handling and Value of the Fiber and Seed, 283.
CHAPTER XXI
Fruit GROWING . ; : : ; : : : 5. apt —olO
Horticulture and Agriculture, 287 — Where Our Fruits
originated, 287 — Developing the Young Tree, 288 — The
Location of the Orchard, 289 — The Distances between
the Trees, 289— Cutting back and Planting the Young
Trees or Vines, 290 — Cultivation of the Young Plants,
291 — The Training of the Young Plants, 292 — When
and how Fruit Buds form, 292 — Conditions which favor
the Formation of Fruit Buds, 298 — Age of Wood upon
which Fruit Buds appear, 294 — The Reasons for Prun-
ing, 298 — Methods of Pruning, 299 — Precautions to be
taken in Pruning, 304 — Protecting Fruit-bearing Plants
from their Enemies, 305— Gathering and Storing the
Fruit, 309.
CHAPTER XXII
VEGETABLE GROWING . ‘ » Cali—329
Cool Season Crops, 311— Warm Season Crops, 312 —
Getting ahead of the Season, 312—In the Garden
xXx CONTENTS
Proper, 315— The First Planting, 317 — When the Dan-
ger of Frost is Past, 328.
CHAPTER XXIII
PERMANENT AGRICULTURE
The Result of selling Crops from the Land, 831 — How
the Three Important Elements of Fertility may be re-
stored to the Soil, 3832-—The Care and Importance of
Barnyard Manure, 386,
EQuIPMENT
PUBLICATIONS ; ; 3 ‘ é ‘ js
INDEX . ; : : ; 3 ‘
PAGES
330-3837
338-339
340-541
343-348
SOILS AND PLANT LIFE AS RELATED
TO AGRICULTURE
SOILS AND PLANT LIFE
CHAPTER I
HOW SOILS ARE MADE AND MIXED
1. What the Soil Is. — The soil, as we now see it, is
composed. of broken-down rock, mixed with decaying
plant and animal matter. For millions upon millions of
years, no doubt, the work of soil making has been going on.
2. Grinding up the Rocks. — The earth was once made
up of rock. Men who have studied the subject long and
carefully tell us that the heat and the cold, the wind and
the water, the gases of the air, the plants, and the animals
have all had a part in breaking down the rocks into rock
powder and mixing it through and through that more
plants and animals might exist. We are told that vast
fields of ice, called glaciers, moved slowly over many parts
of the country ages ago, carrying with them rock masses
and grinding to powder whatever came beneath their
~ mountain-like weight. We read about these great gla-
ciers and see pictures of them as well in our geographies.
We are told also that rocks expand with heat and con-
tract with cold, becoming broken up in this way. We
know that hot water will break a cold tumbler. We have
seen stones cracked or broken about the fire where we
cooked our picnic or camp supper. We have seen where
the water has washed out great hollow places in the rock.
Moreover, we must know that when the cracks and crev-
B 1
Pe SOILS AND PLANT LIFE
ices in rocks become filled with water and freeze, the rocks
are broken apart, just as a jugis broken if the water in it
is allowed to freeze. The particles of rock are not only
-broken and washed into finer and finer pieces but are
Tr asi a Gao ME ee
Fic. 1. — Rock split by freezing.
mixed thoroughly with other kinds of rocks and with de-
caying plants and animals to make the rich, fertile soil
as we know it.
Let us study first, then, how the water mixes and lays
down the soil,
HOW SOILS ARE MADE AND MIXED 3
EXERCISE 1
Object. —To see how layers of soil are made by the
action of water.
Procedure. — Bring half a cupful of soil from any field
at home or from any place near the school. Put half of
it in a pint jar or in a wide-mouthed bottle and the re-
mainder in another. Then fill each a little over half full
of water. Shake well and allow them to stand until the
close of school to-day. Then shake again and set them
aside until class period to-morrow. This is done in order
to break apart all the small lumps. Number the Jars
one and two.
Does the soil seem to have settled in distinct layers?
Which sized particles settled first? Have you not seen
the soil along the bank of a stream in layers like this?
Now shake jar number two vigorously again and allow
the contents to settle one minute. Pour off the water
into a third empty jar, leaving in the bottom of the second
the soil that has settled. Allow the third jar to stand one
hour, and pour off the water into a fourth jar, leaving the
soil that settled in the third jar. Allow the fourth jar to
stand until class time to-morrow.
The soil that settled in one minute is the sand; that, in
one hour is called silt; that, in twenty-four hours, the
clay.
Do you find that the layers of soil in jar number one
look like the soils in jars two, three and four?
Dip a little of the soil out of jars two, three and four
with a small wooden paddle and examine each carefully
with a hand lens and by rubbing between the thumb and
fingers. Which one is pasty? Which is made up of
coarse particles? Would you like to have a field of pure
clay? Why not? Would you like to have one of pure
4. SOILS AND PLANT LIFE
sand? Is it not best to have the sand, silt and clay all
mixed ?
Conclusion. — You have seen the largest stones, or —
pebbles, in the swiftest part of the creek or river, and the
soil in layers near the stream; and you have seen the finest
mud on the top of the soil where the water had dried up
along the roadside. Explain why these things are so.
3. Soil Names, or Types. — We have seen how a soil
may be made up of sand, silt and clay. If it contains a
large amount of sand, we call it a sandy soil; if of clay, a
clay soil. ‘A soil made up of about one half sand, and the
other half silt and clay is called a loam soil. If the per-
centage of silt is large, it is called a silt loam; of clay, a
clay loam; of gravel, a gravelly loam; of stone, a stony
loam.
EXERCISE 2
Object. — To find the percentage of sand, clay and silt
in the soil of fields at home or near the school building.
Procedure. — Secure two or more samples of soil, about
one half cupful each, from different fields. Place each in a
jar, which has first been weighed, and weigh again after
the sample has been put into it. From these weights,
find the weight of each sample. Now separate the sand,
silt and clay just as you did in Exercise 1. Find the weight
of each of these constituents in each sample, taking care
that all appear about equally moist when weighed. These
weights can be determined more easily if all jars used
are first weighed and the weights recorded. After you
have found the weight of the sand, the silt and the clay
in each sample, find what per cent each of these is of the
original sample.
Conclusion. — Do you find any difference in the per-
centage of sand or clay which the different fields contain?
HOW SOILS ARE MADE AND MIXED SS
Ask the owner or your father which field can be plowed
sooner after a rain. Can you tell him why? If a stream
flows through a soil containing considerable sand, the
soil near the water is sandier than that farther away.
Why is this true?
4. Two Sources of Soil Material.— The soils which
we have been studying are made up of a great deal more
than just pulverized rock. Some of the soils, especially
if they came from a field which last year was a pasture or
meadow, or from a fence row, or from the woods, were dark
in color, crumbled easily in our hands, and had that good,
rich “earth ’”’ smell. Along the fence row, the weeds and
grass have grown up, ripened, died down and decayed
year after year. The soil here must contain a great deal
of partly decayed plants, which is called humus. This
makes soil fertile.
EXERCISE 3
Object. — To find out how much of the soil comes from
the rocks and how much from the plants.
Procedure.—Secure a small can full of soil from under an
old fence or from a field which was in pasture or meadow
last year; also another can from a hillside field that has_
been plowed for a number of years, or from the middle
of a well traveled road. Examine each carefully, and
tell all you can about the color and the way each crumbles
in your hand. Make a mud ball the size of a large marble
out of each soil and let them dry for ten days. Then try
to break each one with your fingers or a stick.
Now place five ounces of one of the soils as it came
from the field or fence row in an iron pan or old shovel,
and heat it red hot for at least an hour. Do you see
any change in color? As soon as the soil is cool, examine
it to see if it crumbles as easily as it did before. Heat
SOILS AND PLANT LIFE
oh eee
"YOOI UO LoY}ZBIM PUL PUIM oY} JO UOTOW — ‘gz ‘DIT
HOW SOILS ARE MADE AND MIXED 7
five ounces of the second soil in the same way for at
least an hour. Be sure to tell about any change in color
that may take place during heating. Did any smoke
come off from either soil? Will rocks burn? Will hay,
or grass, or weeds burn? When each soil is cool, carefully
weigh again. Which one has lost the greater weight ?
What reason can you give for this loss?
Conclusion. — Tell which it is, rocks or plants, that
gives a rich soil the dark color and good earth smell.
Tell why it is that a new field can be worked sooner after
a rain than an old one. By scraping the roads we get
all the organic matter, or humus, worked out of them;
and they then bake hard and firm. If a farmer should
burn his cornstalks or straw instead of working them into
the soil again, how would it affect the supply of humus
in his land? Frequent cultivation aérates the soil and
hastens decay. Why will several crops of corn in succes-
sion exhaust the humus in the soil? Land that has been
in pasture is found to be rich in humus. Likewise the
addition of manure increases the amount of humus in the
soil. State two ways in which humus may be added to a
soil which lacks it.
5. The Part Plant Life plays in making Soils. — An
armful of fodder, left lying in the field, or at the bottom
of a haystack, soon begins to decay. The dead plants
become covered with blue-black molds, which are them-
selves living plants, and which are visible to the naked
eye. These molds, or fungi, as they are called, absorb a
part of the fodder. The part which remains is acted upon
by tiny plants, called bacteria, which are too small to be
seen with the naked eye. These work upon the plant
remains until the whole is broken down into simple sub-
stances which the roots of living plants may take up again.
8 SOILS AND PLANT LIFE
When wheat is received at the mills, it is run between
great steel rollers, and it then passes through a long series
of processes until it is separated into flour, bran, middlings
and various other products.
We may compare the changes which take place in a
decaying plant with those which take place in the wheat
as it passes through the mill, but we find a difference.
ioe Or
Ce LAn> B
yen Plant Die,
?
ans Become, LS
Cn SOI c 7
t Becomes
J
Fic. 3. — The cycle from plant to plant again.
The products of the wheat can not be gathered together
again to make the kernels from which they came, whereas
in Nature the plants are broken down and separated by
the molds and bacteria into simple compounds, which
are taken up by roots and finally made again into living
plants. The drawing above will fix in our minds better
than words how this comes about.
6. The Part Animal Life plays in making and mixing
Soils. — A plant may be eaten by an animal. A part
HOW SOILS ARE MADE AND MIXED 9
goes to build up the animal’s body. The rest is thrown
off and becomes a part of the soil. Sooner or later the
animal dies, and its body, too, goes back to the earth
again. Thus we see that soil becomes the meeting place
of the mineral kingdom and the kingdom of life.
Animals not only help to make soils, but they also play a
very important part in mixing them through and through.
Gophers spoil our alfalfa, clover and timothy fields, and
we try to keep them out. The same is true. of ground
hogs, squirrels and other digging animals; and yet these
rodents have for ages performed an important part in soil
making. Each ant-hill is a real soil-mixing mill.
Perhaps the most important visible member of animal
life in soil making and mixing is the common earthworm,
angleworm, or fishworm, as we may choose to eall it.
“These insignificant creatures burrow in moist, rich soil
and derive their nourishment from the organic matter it
may contain. In order, however, to obtain this com-
paratively small amount of nutritive matter, they devour
the earth without any selective power and pass it through
their alimentary tracts, rejecting the non-nutritious
portions, which nearly equal in bulk that first taken in.
The numerous holes made, while in part perhaps to afford
passage to the surface, are mainly excavated in this
process of soil eating, and actually represent the amount
of material which the worms have passed through their
digestive systems. ;
‘“ Darwin states that in certain parts of England these
worms bring to the surface every year, in the form of
excreta, more than ten tons per acre of fine, dry mold, ‘so
that the whole superficial bed of vegetable mold passes
through their bodies in the course of every few years.’
By collecting and weighing the excretions deposited on a
small area during a given time, he found that the rate of
10 SOILS AND PLANT LIFE
accumulation was an inch in every five years. The im- .
portance of the worms, both as mellowers of the soil and
as levelers of inequalities is therefore very great.”
7. Elements in the Soil and Air which Plants must
have in Order to make a Healthy Growth. —In this
brief lesson, we have learned that soil is made up of pow-
dered rock and decaying vegetable and animal matter.
We have learned how they are mixed by various agents.
The soil contains a large number of distinct substances
called elements. Only ten of them, however, are essential
to plant growth. Their names together with their chemi-
cal symbols are given below :
Carbon (C) Nitrogen (N) Potassium (K)
Hydrogen (H) Sulfur (S) Calcium (Ca)
Oxygen (O) Phosphorus (P) Magnesium (Mg)
Iron (Fe)
We shall learn in chemistry of the various ways in
which these elements combine in the soil to form plant.
food. It is enough here for us to know that without any
one of them a plant can not make healthy. growth.
Carbon, as usually seen, is a black solid. Coal and
charcoal owe their black color to the fact that they are
nearly pure carbon. This element comprises about a
half of the dry matter of all plants, that which is present
in coal and charcoal coming from plants that have lived
in the past. All of our foods likewise contain carbon,
which accounts for their turning black, or charring, when
burned. Under certain conditions, carbon will unite
with oxygen, forming carbon dioxide, a gas which is
found in the atmosphere. The leaves of plants take this
gas from the air, and in this way, plants get all their
HOW SOILS ARE MADE AND MIXED 11
carbon. It is the only element which they do not take
from the soil.
Hydrogen and oxygen are odorless, invisible gases.
They are not at all alike, but will unite with each other,
the compound formed being water,
H,.0. Plants of course draw a great
deal of water from the soil, and from
this water they take the hydrogen
and oxygen which they must have in
order to live.
Nitrogen, too, is an invisible gas,
but it differs greatly from both
hydrogen and oxygen. It com-
prises nearly four fifths of the at-
mosphere ; yet plants, whose leaves
are held aloft in it, can take none
whatever from the air. Instead,
Fic. 4. — Plants growing in water cultures.
A, plant receives all the essential elements; B, plant receives all
essential elements except nitrogen; C, plant receives all essential
elements except phosphorus; D, plant receives all essential elements
except potassium.
it combines with other elements; and the compounds
so formed, which are found in the soil, are dissolved
and carried upward into the plant by the soil water.
Sulfur is commonly seen as a yellow powder, which
produces suffocating fumes when burned. Phosphorus is
1 SOILS AND PLANT LIFE
less familiar to us. Because it is so easily ignited, it is
much used in making matches. Jron, potassium, calcium
and magnesium are metals. These six elements combine
in many different ways in the soil, forming compounds
which, like those of nitrogen, are dissolved by the soil
water and carried along by it when it passes upward into
the plant.
There are very few soils which are deficient in any of
the essential elements save nitrogen, phosphorus and potas-
sium. The great problem of maintaining a sufficient
supply of these three elements in the land so that agricul-
ture may be carried on perpetually remains one for the -
consideration of all people who till the soil or expect to
continue to get from it an adequate food supply. The
strength of nations has always been drawn from the soil.
A system of permanent agriculture is therefore indispensa-
_ ble to the prosperity and happiness of our people. As a
fitting close to our first study of agriculture, we shall
make our last lesson one on maintaining the fertility of the
soil.
QUESTIONS
1. Define the term soil.
2. From what three kingdoms do the materials for soils
come?
3. Name three agents which have helped to break down rock.
Tell how each works.
4. How can you separate soil into clay, sand and silt?
5. Name three agents which have helped to mix soil. Tell
how each works.
6. Define humus. How does a soil feel, when handled,
and how does it smell when it contains plenty of humus?
7. Compare the weight of a cupful of soil containing plenty
of humus with one lacking humus.
8. Name the ten elements essential to plant growth and tell
how the plant gets each one.
9. What part of the dry matter of plants is carbon?
CHAPTER II
THE WATER IN THE SOIL
A soIL may be ever so rich in both mineral and organic
matter and yet lack water. There can be no crops unless
water is added to the soil in the form of rain or by means
of irrigation.
8. How the Soil loses Water.— We may liken the
soil to a great sponge, standing ready to receive whatever
moisture comes to it. Soils, like sponges, vary in their
ability to receive and hold water. Rain or irrigation
water received by the soil is lost or escapes in four ways:
First: it runs off the surface.
Second: it filters down through the soil and drains
away.
Third: it evaporates from the surface as standing water,
or as water which was first taken in by the soil and later
worked its way to the surface.
Fourth: it is taken in by the roots of plants and escapes
as water vapor from their leaves.
9. The Water which runs off the Surface. — The
amount of water which runs off from any soil depends of
course upon the amount of rain, the rate at which it falls
and the amount of moisture already in the soil. There is
another factor, however, greater than any of these; the
rate at which the soil can take up water and the capacity
of the soil to hold water. Let us prove that this is true.
13
14 SOILS AND PLANT LIFE
EXERCISE 4
Object. —'To see how soil types vary in the rate at
which they take up water.
Procedure. — Tie pieces of cheesecloth firmly over the
small ends of three lamp chimneys or glass cylinders.
Fic. 5. — Adding water to the soil.
Fill the first one with clay, the second with silt, the third
with sand. These soils should be air dried, and then
worked through a piece of fine screen wire. Tap the
chimneys or cylinders firmly on the table to settle the soil.
Place the tubes in a rack, and proceed as shown in the
following illustration.
Three tumblers or cups of equal capacity should be
THE WATER IN THE SOIL 15
used, so that each cylinder may receive the same amount of
water. Record the time when you begin, and see how
long it takes each soil to take up the water, how long it
takes the water to reach the bottom of each chimney, or
cylinder, after being added at the top, and how much
water passes through each soil in a given time. The
amount of water that passes through each soil may be
collected in glasses below the chimneys and measured.
A table like this will help you to keep an accurate record
in your notebook :
TIME RE-
Rea ae TIME WATER QUIRED FOR | WHICH PASSED
SorL EACHED SoIL TO TAKE | THROUGH SOIL
WaTER ADDED BorTrom uP Cup oF IN TEN MInN-
WATER UTES
Sand . . ..| 9:30 a.m. | 9:34 4.m. | 8 minutes + cup
Slices cee f (2 O30 AM
olay es = 2c) 9730 ALM.
Conclusion. — There are millions of acres of sandy
hills in the United States and there are scarcely any gullies
washed in them. Clay hills are always full of washouts.
How long did it take the clay to take up the cup of water?
Why do the clay hills wash so much worse than those
made up largely of sand?
EXERCISE 5
Object. — To determine the relation of the amount of
humus in the soil to the amount of water it will take up and
hold.
Procedure. — Fill a can with soil from the middle of a
well traveled road; another with soil from an old fence
row near by, so that the two soils will be as nearly alike
as possible except for the amount of organic matter which
16 SOILS AND PLANT LIFE
each contains. Dry them in air and sift each one. Secure
other samples if possible, being careful to get two of each
type of soil, one of which is worn out while the other is
rich in humus.
Cut holes about one inch in diameter in the bottom of
tomato cans, if you do not have on hand those prepared
for this exercise. Place a piece of screen wire over each
hole, then a piece of cheesecloth over the wire. Fill as
many of these cans level full as you have samples of soil.
Label each one, for instance, ‘Sandy Loam from the
Center of the Road,” “‘ Sandy Soil from Old Fence Row,”
etc. Remember always to work them in pairs, the worn
out and the rich soil of the same type. Carefully record
the weight of each can both before it is filled with soil and
afterwards so that you can tell exactly how much soil is
in each one. |
Place the cans in a pan or bucket and pour water around
but not on them. It should stand within one half inch
of the top of the cans. At the class period the following
day, remove them and set them in a cool place to drain.
After two days weigh each can again.
Conclusion. — Tell how much water each soil has taken
up. Figure the percentage of moisture taken up and
held by the soil in each can. A soil containing plenty of
humus does not dry out as readily as one poor in humus.
Why? Ask your father or any good farmer in the neigh-
borhood which field dries out first, one which was in pasture
or meadow a year or two ago, or one which has been cul-
tivated for a number of years. Ask him if a clay soil,
rich in organic matter, dries out as soon as a sandy one.
Summarize all this information in your conclusion.
10. The Water which filters down through the Soil
and drains away.— The sky may be clear overhead.
THE WATER IN THE SOIL LZ
Perhaps we have had no rain for two or three weeks ;
yet here may be a bubbling spring, or there a clay tile
running full of water. |
First, let us consider the source of the water of the
spring. Water, as it falls from the clouds, is taken up
more or less readily by the soil. It filters down through
Fic. 6. — Running tile.
silt, sand, gravel or whatever it may be until it reaches
some layer which will allow it to flow downward no further.
It then flows along this layer until on some lower ground
it comes to the surface. Whenever water issues from a
natural opening, we call it a spring.
There are millions of acres of land throughout the
United States from which water can not drain naturally.
c
18 SOILS AND PLANT LIFE
As we shall soon learn, this water must be removed before
plants can make a healthy growth.
Some artificial means, then, must be adopted to remove
this free moisture. This is accomplished by the use of the
tile drain. If all the tile drain which is now laid in the
states of Iowa and Illinois alone were placed end to end,
it would make a continuous line tens of thousands of miles
in length.
11. How Water enters Drain Tile. — Since the water
escapes through these drains, the question at once arises,
How does it get into the tile? Does it enter at the joints
or through the walls of the tile?
Fit a cork firmly into a hole in the bottom of a flower
pot. Fill the pot with water. Has any water escaped
through the walls of the pot at the end of an hour? Of a
day? If little or no water can escape through the walls
of pots, little or none can enter. Flower pots and drain
tile are made of the same material. This means, then,
does it not, that water enters at the joints of the
tile.
Lines of tile are laid not closer than a rod apart as a rule,
and often they are two rods apart. How is all the water
from this area of soil to escape through one small tile?
Does it enter at the top, the sides, or the bottom when it
finds its way through the joints into the drain?
EXERCISE 6
Object. — To see how and where water enters the tile
drain.
Procedure. — Fill a quart can with fine sand or sandy
loam. Punch three holes in the can with a nail: one
about three fourths of an inch from the bottom; the
second the same distance above the first and a little to the
THE WATER IN THE SOIL 19
right of it; the third about three quarters of an inch
above the second and a little to the right of it. Make a
cup-shaped hole in the top of the soil and add water until
it begins to flow from each of the holes in the side of the
can.
Conclusion. — From which hole did the water first
begin to flow? Let the lowest hole represent the bottom,
the middle one the side, and the highest one the top of the
tile. Does this not mean that the water must fill the soil
from the bottom upward, then work its way laterally
through the soil until it reaches the tile, entering the
joints at the bottom? From here it flows out to the
drainage ditch or natural outlet. Trace a given amount
of water from a rain cloud through a tile-drained soil to
the creek or river.
12. Three Kinds of Water in the Soil. — We have just
been studying how a certain amount of water escapes
from the soil. This water, which moves through the
soil and drains away, is known as free, or gravity, water.
It is of no benefit to plants whatever. On the other hand,
it is an absolute detriment to them. When this gravity
water has drained away, there remains a tiny film about
each soil particle, known as film, or capillary, water. This
is the moisture, of which the plant makes use. There is,
however, still another kind of moisture, known as hygro-
scopic moisture. It is the water which may be driven off
by heating the soil to a high temperature after it is thor-
oughly air dried. It plays no part whatever in plant
growth.
EXERCISE 7
Object. — To determine the percentage of each kind of
water in a soil.
Procedure. — Secure a tomato can or a tin can with a
20 SOILS AND PLANT LIFE
cover and remove the bottom with a can opener. Press
lid into place and invert the can. Place first a piece of
screen wire and then a piece of cheesecloth on the inside
of the can next to the lid. Fill the can level full with any
soil you may select from your air-dried and screened
samples. Carefully weigh the can and soil. Add water
until the whole soil mass is saturated and the water stands
on the surface. Carefully weigh again. Remove the
lid from the bottom of the can and allow the water to
drain out for at least two days. Carefully weigh a third
time. Spread the soil on a cloth or in a large shallow pan
and allow it to dry in the open or near a stove for two or
three days. Weigh a fourth time.
By heating over a slow fire without burning, the
amount of hygroscopic moisture present could be de-
termined; but since this is rather difficult, it is not
required here.
The moisture first lost was the gravity, or free water ;
that in the sunlight or near the stove, the film water ;
that, which would be lost in the oven or in a pan over a
slow fire, the hygroscopic.
The following table will assist you in keeping your
notes :
WEIGHT OF | WEIGHT OF
CAN AND CAN AND
SoIL AFTER | SOIL AFTER
DRAINING DRYING
WEIGHT WEIGHT OF
oF Can Can, Soin
AND SoIL | AND WATER
KIND or WEIGHT
Soi. or Can
THE WATER IN THE SOIL 21
Conclusion. — Figure the percentage of gravity and
film moisture in the soil. If others have worked with
different kinds of soil, compare your results with theirs.
13. How Film Moisture works its Way upward in the
Soil. — The film moisture held in the soil tends to work
its way upward toward the surface. This is called capil-
lary action. We may know that water will rise a short
distance in a very small glass tube when we thrust it into a
pail of water. We know a lamp wick pulls up oil by the
same process. The soil is full of these tiny tubes, which
are not straight, to be sure, since they consist of irregular
openings between the soil particles; and through them
the moisture rises from the subsoil. Do these tubes
vary in size in different soils?
EXERCISE 8
Object. — To record the rate at which film moisture rises
in different soils.
Procedure. — Repeat Exercise 4, but set the lower end
of the chimneys in pans of water instead of adding water at
the top. Raise the lower end of the chimneys slightly from
the bottom of the pan by thrusting a toothpick or splinter
under one side. Otherwise the water may not enter freely.
Conclusion. — Record the length of time it took the
moisture to reach the surface of the soil in each cylinder
or chimney. Tell why it rose quickly in some and slowly
in others.
Since the moisture in the soil rises through these capil-
lary tubes, as we have just shown, is it not important to
keep them unbroken?
EXERCISE 9
Object. — To study the effect of breaking the capillary
tubes in the soil by plowing under clods or heavy straw.
22 SOILS AND PLANT LIFE
To study the effect on the rise of water in the soil of
discing stubble or trashy ground before plowing.
Procedure. — Fasten cheesecloth firmly over the lower
end of chimneys or glass cylinders as you did in Exercises
4 and 8. Fill the first chimney full of fine, sifted soil.
Fill the second one two thirds full of the same soil, then
add a small handful of fine clods, then soil again until the
chimney is full. Fill the third chimney exactly as you
Courtesy Iowa State College.
Fic. 7. — Farmer discing.
filled the second, only substitute a half inch of fine straw
for the clods. Fill a fourth chimney as you did the
third, but instead of putting the straw in a layer, cut and
mix it thoroughly with the soil in the upper part of the
chimney. Note that while the straw in the third chimney
is in a layer, just as it would be if we plowed stubble
without discing, that in the fourth chimney is mixed with
the soil just as it is when stubble is disced before plowing.
THE WATER IN THE SOIL 23
Place the lower ends of the chimneys or cylinders in
pans of water, and watch the moisture rise in the soil.
Conclusion. — Will it pay to dise stubble or trashy
fields before plowing? Why? What is an ideal condi-
tion of the soil for the freest rise of moisture through it?
14. How the Farmer prevents the Escape of Film
Moisture. — The roots of plants often feed very near the
surface of the soil. These roots need the moisture that
comes up by capillary action. The farmer wants there-
fore to bring this water up to the roots, and yet not to let
it escape into the air. He can do this by mulching with
straw, but this may keep out the air, which we shall later
learn is very important. Moreover, it would be out of
the question for him to mulch all his fields in this way.
A mulch, then, of soil, or a dust mulch, as it is called, is
used. The following simple demonstration will show
how a dust, or powder, will prevent the moisture from
reaching the air:
Place two lumps of sugar in a saucer containing a small
amount of water colored with red ink. On the top of one
of the lumps, place half a spoonful of powdered sugar,
soda or starch. Notice how the colored water comes to
the surface of the first lump and stops at the powdered
material in the second.
QUESTIONS
1. Name four ways by which water escapes from the soil.
2. Which takes up water more rapidly, a sandy soil or a
clay soil?
3. Which takes up water more rapidly, a soil rich in humus or
one lacking in humus?
4. Define the term spring.
5. Explain what causes the water to issue from a spring.
6. Explain fully how water enters a tile drain.
es SOILS AND PLANT LIFE
7. What three kinds of water do we find in the soil ?
8. How can you determine the amount of each kind of water
in a sample of soil?
9. What is the effect upon the rise of water in the soil of
plowing under trash or clods?
10. How may moisture be prevented from escaping from
the surface of the soil?
* CHAPLET
THE ATR IN) THE SOLE
TILLABLE land is made up of soil particles, each of which
is inclosed in a film of moisture while the spaces between
them are filled with air. A square rod of ordinary soil
may contain from sixty to seventy-five cubic feet of air
in the upper fourteen inches.
15. Why Air is Necessary in the Soil. — Air, which
consists chiefly of oxygen and nitrogen, plays a very
important part both in soil-making and in plant growth.
We have already learned that plants, decayed through
the action of fungi and bacteria, help to form soil. These
organisms, you will remember, break down the dead
plants into simple compounds which the living roots can
absorb again. (See Section 5.)
The fungi and bacteria which cause decay can not live
without oxygen, nor can the roots of plants live without
it. Moreover, a germinating seed takes in oxygen and
throws off carbon dioxide. In fact, as we shall later
learn, it is impossible for any seed to germinate without
oxygen.
In addition to oxygen and nitrogen, air also contains
carbon dioxide. This gas, which is given off by germinat-
ing seeds and decaying vegetable matter, helps to dissolve
the plant food in the soil.
16. Why we seek to control the Air Space in the Soil.
— Since the air in the soil is so essential to plant growth
25
26 SOILS AND PLANT LIFE
and soil-making, it follows that any method we may em-
ploy to get more air into the soil will ordinarily increase
its fertility. In regions, however, where the rainfall is not
sufficient to settle the soil well or to allow the decom-
position of the organic matter, the amount of air in the
soil may be too great. In this case, the upward move-
ment of water, such as was shown in Exercise 8, will be
interfered with, and not enough moisture will reach the
roots or germinating seeds. The aim of the farmer in
these dry regions is to increase the moisture-holding ca-
pacity of the soils without making them so light that the
movement of the air will dry them out.
The amount of air a soil contains depends (1) upon the
character of the soil, (2) upon the amount of organic
matter it contains and (3) upon the amount of moisture
present.
EXERCISE 10
Object. — To determine the amount of air space in the
soil.
Procedure. — Secure as many ordinary tin cans as you
have samples of fertile and infertile, air-dried and sifted
soils. Fill each can with a soil and tap lightly on the table
to settle it. The space between the soil particles is now
occupied by air. Add water slowly to each can, keeping
a careful record of the amount.
When the water has displaced all the air and stands at the
surface of the soil, you will be able to determine the amount
of air in the sample by the amount of water that has been
required to displace it.
Conclusion. — State which soils contain the greatest
amount of air space. Does the amount of organic matter,
or humus, make any difference in the amount of air the
soil contains? Why is it that a soil needs air?
THE AIR IN THE SOIL 26
EXERCISE 11
Object. — To determine the influence of compacting the
soil upon the amount of air space in it.
Procedure. — Follow the instructions given in Exer-
cise 10, only before adding the water thoroughly pack the
Fic. 8. — Measuring the water before adding it to the soil.
soils in the cans with a short piece of broomstick or the
head of a small mallet.
Conclusion. — Compare the amount of air space in the
soil before packing, as determined in Exercise 10, with
that after packing, as found in this exercise. In dry
farming regions, where the soil is liable to be too loose and
light, would it be advisable to roll or pack it?
28 SOILS AND PLANT LIFE
17. How we may get More Air into the Soil. — From
the western limit of the Corn Belt to the Atlantic Ocean
and in all the land subject to irrigation, there is need of
plenty of air in the soil. This does not mean that large
air spaces, such as are caused by clods or small piles of
weeds or straw, are necessary; it means rather that much
Fig. 9. — Farmer plowing.
of the air which finds its way into the small spaces in
mellow, well-tilled land is needed.
The amount of air in the soil is influenced first by cul-
tivation or tillage; second, by manuring; third, by
drainage; fourth, by rotation of crops.
The plow turns up particles of soil which may have
been shut off from a supply of air. Then, too, the bottom
of the furrow is in direct contact with the air until it is
covered on the next round.
/
THE AIR IN THE SOIL 29
Harrowing, discing and cultivating all help to increase ,
the amount of air in the soil. Rolling and subsurface
packing, on the other hand, diminish the amount of air in
the soil. These latter operations are performed largely
in the dry farming regions.
How much more water did the soil containing humus
take up than the same soil lacking humus in Exercise 10?
Remember that it was there shown that the air space in a
soil increases with the amount of humus, or organic matter,
which it contains. By adding manure to the soil, we
increase the amount of air in it.
In Exercise 10, we expelled the air from the soil by add-
ing water. When we remove water from the soil by tile
drains, we allow air to take the place of the water. More-
over, a generous supply of air enters these tiles and moves
upward through the soil.
Many plants, such as alfalfa and sweet clover, send
their roots deep into the soil. When these crops are
plowed up, the roots decay, allowing the air to fill the
space which they had occupied. This is one of the bene-
_ fits of crop rotation.
QUESTIONS
1. What are the uses of air in the soil?
2. How many cubie feet of air may the upper fourteen inches
of a square rod of soil contain ?
3. What influence has plowing and discing upon the volume
of air in the soil?
4. Why is it that farmers in the dry farming regions work
to reduce the volume of air in their soils?
5. What influence do clods have upon the soil air?
6. Name two ways in which tile drains help to get air into
the soil.
7. What influence has manuring upon the amount of air
in the soil?
8. How does the rotation of crops influence soil air?
CHAPTER IV
THE TEMPERATURE OF THE SOIL
18. Proper Temperature Necessary for Germination.
— Throughout the winter months, the seeds and roots of .
plants in the earth lie dormant. Plant food, moisture and
air are present in the soil; but the proper temperature is
lacking. Seeds can not germinate, nor plants grow unless
the soil absorbs enough of the heat of the sun to raise the
temperature of the fields somewhat above freezing. Very
few of the seeds or plants awaken from their winter’s
rest at a temperature near thirty-two degrees Fahrenheit,
the melting point of ice. Wheat will germinate and make
some growth at forty-one degrees but it thrives best at
eighty-three. Oats may germinate at thirty-eight; their
most vigorous growth, however, is made at seventy-seven
degrees. The soil in a cornfield should register a tempera-
ture of at least forty-nine degrees, while ninety-two degrees
is the best, or optimum temperature for the germination
of this seed. Cucumbers, muskmelons and squashes
should not be planted until the oaks are fully in leaf, when
the soil temperature is around eighty degrees.
19. How Temperature of the Soil is governed. —
Since a warm soil is so important a factor in the germina-
tion of seeds and the development of roots, let us consider
the laws that govern the temperature of the soil. These
laws, or principles, may be summarized in three sentences :
The temperature of the soil depends first upon the
amount of air space in it.
30
THE TEMPERATURE OF THE SOIL ol
The temperature of a soil depends secondly upon the
amount of moisture in it.
The temperature of a soil depends thirdly upon its
color.
20. How the Air Space in a Soil affects its Tempera-
ture. — The greater the amount of air space, the warmer
the soil. Air is warmer than the earth in the spring.
Therefore when either air or rain water, which is warmed
in passing through the air, enters the soil in the spring,
the temperature of the land is raised.
We have already in Exercises 10 and 11 determined the
amount of air space in certain soils. Let us now see what
influence this has upon the temperature. We remember
from Exercise 1 that while sand is made up of coarse
particles, clay consists of particles so small and fine that
it becomes pasty when wet.
EXERCISE 12
Object. —'To determine how the size of particles, and
consequently of the air space in a soil, influences its tem-
perature.
Procedure. — Fill two cans, one with clay, the other
with sand. Plunge the bulb of a thermometer into each
soil, about one inch below the surface. Moisten each
soil and place the cans in the sunlight. Copy the follow-
ing table into your notebook and complete it by recording
the temperatures every hour.
Soin 9 A.M. 10 a.m. 11 a.m. 12 a.m. 1 P.M. 2 P.M. 3 P.M.
Sand
Clay
32 SOILS AND PLANT LIFE
Conclusions. — Market gardeners always try to select
a dark, sandy soil for their early vegetables. Give one
reason why this kind of soil warms up earlier in the spring.
Lime, added to a clay soil, tends to gather the fine parti-
cles into small grains. Would you expect the tempera-
ture of a clay soil to be somewhat higher after a dressing,
Fic. 10. — Thermometers in the soil.
or application of lime was added? In Exercise 10, the
amount of air space was found to be greater in the soil
containing humus from the old fence row than in that
from the center of the road. Would you expect the tem-
perature of the soil in the sun along the fence row to be
higher than that in the center of the road? Why? If you
eee ee
THE TEMPERATURE OF THE SOIL Oo
have time, test with the thermometer to see if your answer
is correct. Summarize your answers into a short story
about the influence of air space upon the temperature of
soils.
21. How the Moisture in a Soil affects its Tempera-
ture. — We all know that a wet, soggy soil, which is filled
with free or gravity water, 1s much colder in the spring
than is a well-drained soil, which contains only film mois-
ture. Let us investigate this with our thermometers.
EXERCISE 13
Object. — To show the influence of the amount of mois-
ture in a soil upon its temperature.
Procedure. — Fill two cans from the same sample of
soil; that is, with soil from a fence row, from a cultivated
field, or from a garden as you may choose. Add water to
the first can until it stands at the surface of the soil.
Add none to the second can. Plunge the bulb of a ther-
mometer about an inch below the surface of each soil.
Prepare a table as you did in the preceding exercise, but
substituting the words “ saturated soil’? and “ dry soil ”’
for “sand ”’ and “ clay.’’ Place the cans where both the
sun and the wind will strike them.
Conclusions. — Men often wrap a piece of a sack about
a jug in the summer time to keep the water cool. The
sack is usually kept moist so that water is evaporating
from it all the time. Evaporation is a cooling process.
In which soil did the thermometer read lower, that which
was saturated, or the other one? Why? What is one
of the great benefits of tile draining? Which soils will
allow ready passage of water through them, those con-
taining plenty, or little, of humus? Why? Sandy soils,
or clay soils? Why?
D
34 SOILS AND PLANT LIFE
22. How the Color of a Soil affects its Temperature. —
It is a peculiar fact that dark colored things absorb more
of the sun’s heat than do those which are light colored.
That this is true of soils is shown by the following experi-
ment:
EXERCISE 14
Object. — To determine the influence of the color of a
soil upon its temperature.
Procedure. — Fill two cans to within an inch of the top
with any soil you may choose. Fill the remainder of one
can with some white powder, as slaked lime or chalk dust,
the other with coal dust or soot. Thrust the bulb of a
thermometer into each can to a depth of about an inch.
Record the temperatures one hour after the two cans have
been placed in the sunlight.
Conclusions. — White reflects light, black absorbs it;
and when light is absorbed, it is converted into heat.
Is not a dark suit or dress warmer in the summer than a
white one? Why? Should a light colored horse stand
more heat in the summer time, other things being equal,
than a black one? Why? If time permits, compare the
temperatures of light and dark colored soils in the fields.
Are the fields to which green or barnyard manure was
added a year or two ago darker in color than those to
which none was added? Are the fields which were in
clover or pasture last year darker than those which have
been continuously cultivated ?
Name four ways by which a farmer may make the soil
of his fields warmer.
23. The Advantages of a Warm Soil. — Seeds awaken,
or germinate, much more readily in a warm soil than in a
cold one. The growing plant also thrives better where
the soil temperature is favorable. The bacteria and
THE TEMPERATURE OF THE SOIL 35
other organisms in the soil, which break down the dead
plants, work much more rapidly at the higher tempera-
tures. The soil is a storehouse of plant food. A certain
amount of this must be unlocked each year to supply the
plants. Plant food becomes available in a shorter time
if the soil is warm. :
QUESTIONS
1. Why are plants dormant in the winter ?
2. At what temperature will corn germinate best ?
2 At what temperature will wheat germinate best ?
4. Upon what three things does the temperature of the soil
depend?
5. Compare the temperatures of a sandy and a clay soil and
give reasons for the difference.
6. Why will adding lime to a clay soil raise the temper-
ature?
7. Compare the temperature of an undrained field which is
wet with that of a drained field and give reasons for the differ-
ence.
8. Why is a dark colored soil warmer than a light colored
one?
9. How may a person change the color of his soil?
10. What benefits are derived from a warm soil ?
CHAPTER V
THE TILLAGE OF SOILS
24. Why we till the Soil,— The question of tillage
of soils is so interwoven with that of air in the soil, water
in the soil, and the temperature of the soil that it is
difficult for us to set it aside as a separate lesson. There
are, however, some deep and fundamental objects of
tillage which we should fix in mind. We till the soil:
First: to improve its texture and structure. |
Second: to cover, or to work into the soil trash, straw,
manure or plants by plowing or discing.
Third: to put seed into the prepared seed bed.
Fourth: to destroy weeds.
Fifth: to prevent the escape of moisture from the soil by
making a dust mulch.
Sixth: to enable air and water to enter the soil.
25. Improving the Texture and Structure of the Soil. —
If we are to study how tilling the soil will change its texture
and structure, we must know the meaning of these terms
as applied to farm lands. The size of the individual
particles in the soil determines its texture. The manner
in which these particles fit together determines the structure.
The question at once arises. How does tillage change
the size of particles? It can not, in itself, change the
texture of the soil, for the particles are broken up by might-
ier forces than the plow, or harrow, or disc. These opera-
tions do, however, expose the soil particles so that the sun
and the water, the heat and the cold, can break them into
finer particles.
36
THE TILLAGE OF “SOILS S04
There are two ways in which the particles of soil may
fit together, and hence two soil structures are commonly
recognized :
First: that in which the particles are stuck together in
tiny masses, forming what is known as the crumb structure.
Second: that in which the particles are run together
in large masses, forming lumps, or clods. This is known
as the puddled structure.
The formation of lumps and clods; 7.e., the puddled
structure, may be brought about in four ways: (1) by
plowing the ground when it is too wet; (2) by allowing
animals to trample the fields when the soil is full of mois-
ture; (3) by leaving the fields too long in one crop; and
(4) by neglecting to add organic matter.
EXERCISE 15
Object. —'To show the effect of freezing upon the
structure of soils.
Procedure. — Make four mud pies out of clay such as
was obtained in Exercise 1. These pies should be about
an inch and a half in diameter, one half inch thick, and
contain enough water to prevent cracking when molded.
Set one pie on a window sill or on a shelf to dry. It
should not be allowed to freeze. Place the other three
outside the schoolroom where they will freeze thoroughly.
Bring them into the schoolroom after they have been frozen
solid for a day or two, and thaw them out carefully. As
soon as the frost is out of them, but while they are still
wet, place one upon the window sill or shelf inside the
schoolroom, and the other two outside to freeze thoroughly
again. Bring the two frozen pies in again later; and
when they have thawed out a second time, set a third
one on the shelf, and put the last one out to freeze once
38 SOILS AND PLANT LIFE
more. Remember that this pie should not have been
allowed at any time to lose its moisture. Bring it again
into the schoolroom, thaw it out gradually, and put it
on the shelf with the others.
Conclusions. — Break and crumble each of the pies in
your hand. Remember that one of them has not been
frozen at all, another has been frozen once, the third, twice,
and the fourth, three times. Record in your notebook
which one crumbled most easily, which one next, etc.
What did the freezing do to the particles of soil which
had been stuck together by pressure of the fingers while
wet? Have you not noticed how much more mellow a
soil is in the spring than in the fall? What are some of
the advantages of fall plowing?
EXERCISE 16
Object. —'To determine the effect upon structure of
working organic matter into the soil.
Procedure. — Make a mud pie out of clay as you did
in the preceding exercise, only just moisten it instead of
making it wet. Make a second one in the same way, but
make it of one part sawdust, peat or powdered leaf mold,
and two parts clay. Mix the ingredients dry before
adding water. Make a third and fourth pie as you did
the first two, but using sand instead of clay, then a fifth
and sixth one, using silt in the same way. Put the pies
in an oven, on the radiator or on the back of the stove to
dry them out thoroughly.
Conclusions. — Crumble each pie carefully in your
hands. Which crumbles more readily, the clay alone, or
the clay and organic matter? Did the addition of the
organic matter have as much effect upon the silt as upon
the clay? Did it not have least effect upon the sand?
In which soil are the particles smallest? Would you say
THE TILLAGE OF SOILS 39
then that clay soils need green and barnyard manures
more than sandy ones as far as structure is concerned?
Which of all these soils could be plowed first after a rain?
Fic. 11. — Adding organic matter to the soil.
26. One Cause of Cloddy Fields. — The next experi-
ment will bring out one of the common causes of the
cloddy fields which often prove troublesome to farmers.
EXERCISE 17
Object. —To study the effect of stirring or tramping
soils when wet.
Procedure. — Make three groups of mud pies out of
clay, silt and sand; or use types of soils from the fields in
which these materials predominate. Each group is to
consist of one pie of clay, one of silt and one of sand. If
the soil is brought from the field, it will probably be moist
enough for the pies of the first group. If the soil is dry,
add just enough water to moisten and put it in the con-
dition of well tilled land. To each pie of the second
40 SOILS AND PLANT LIFE
group, add enough water to make the soil sticky. To the
third group, add water until the whole is a saturated mass.
In this case, the clay, the silt, and the sand, of which the
different pies are‘made should be thoroughly worked in
your hands. Set the pies in the oven or on the back of
the stove to bake.
Conclusion. — After baking, crumble each pie care-
fully in your hands, making note of how hard each one
is to crush. Would you say that plowing or trampling a
sandy soil would puddle it as much as it would a clay
soil? Would it puddle a silt soil as readily as a clay
soil? What effect would the addition of organic matter
have on each of these soils?
27. Covering, or Working into the Soil, Organic Matter.
— As already stated, the second object of tillage is to
cover or work into the soil any organic matter which may
be on the surface. This may be accomplished by using
the plow or disc.
With the plow, a narrow strip of land is turned up,
twisted over and laid bottom side up. Where there is
any great amount of trash or straw on the ground, a roll-
ing cutter, or coulter, as it is called, is used. This rolling
knife cuts through the trash so that it can not gather, and
lift or clog the plow.
If tall weeds, green manuring crops, or any other plants
are plowed under, some means must be employed to
draw them down to the bottom of the furrow, allowing
the dirt to cover them completely. A chain or a bent
rod is commonly used to draw the heavy plant growth
under the overturning furrow slice.
28. Putting Seed into the Seed Bed. — The operation
of seeding will be studied again in connection with certain
THE TILLAGE OF SOILS 4]
crops. The work of seeding generally stirs or tills the
soil to a considerable extent. A small furrow is usually
opened by the drill shoe, or the planter blade; and the
dirt is filled in again over the seed by some shovel or
wheel attachment behind.
Fig. 12. — Farmer harrowing.
29. Destroying Weeds. — One of the primary objects
of tillage is to destroy weeds. The tool which is used
depends upon how deeply or thoroughly we wish to cul-
tivate the soil, in addition to killing the weeds; and it
42 SOILS AND PLANT LIFE
depends also upon the size of the weeds and the nature
of their root system. Any plant is most easily destroyed
when it is just breaking through the ground. The com-
mon harrow is one of the best tools we have for destroying
young weeds.
As the weeds become a little older, the dise or cultiva-
tor is used to destroy them. The disc is not used, however,
on such plants as the quack grass. This weed is spread
by long, underground stems, which run about beneath the
surface at a depth of two or three inches. A dise only
serves to cut these stems into pieces and scatter them
through the fields, where each piece becomes a new plant.
Such weeds are plowed up, exposing the roots to the sun
without breaking them any more than necessary.
30. Forming a Dust Mulch. — In Section 14, we ob-
served how the moisture rises through the soil until it
escapes into the air unless prevented by a dust mulch.
Such a mulch may be formed and maintained with the
harrow, the fine-toothed cultivator, or with the subsurface
packer, which is extensively used in the dry farming regions.
31. Making it Possible for Air and Water to enter the
Soil. — Plants can not exist without air and water. The
roots and germinating seeds, as well as the leaves and
stems, must have air. Plants absorb no moisture through
their leaves or stems; the roots alone gather the water.
We have already seen in Section 16 why the soil needs air.
It must be put in condition to receive and hold this air
and water.
The plow stirs the soil, making it light and friable;
the harrow breaks the lumps, making the earth even more
mellow; and the cultivator loosens the surface so that
the rain will not run off and that the air may enter.
THE TILLAGE OF SOILS 43
QUESTIONS
1. Give six reasons for tilling the soil.
2. Define the terms texture and structure as applied to soils.
3. What effect does freezing have upon the structure of
soils?
4. Name two soil structures.
5. Name two ways of bringing about the crumb structure.
6. Name four causes of a puddled condition of the soil.
7. How ean you draw tall weeds or other plants under when
you plow?
8. What is the best implement to use to destroy weeds that
are just sprouting? To destroy weeds an inch or two high?
To destroy tall weeds?
9. What is the use of a dust mulch, and how is it maintained ?
10. How does cultivation help air and water to enter the soil?
CHAPTER VI
THE ROUND OF PLANT LIFE
Tuus far our lessons have been about soil, for from the
soil plants draw their moisture and all of their food except
carbon. Plants can not exist without soil; neither can
soil exist without plants. The two are inseparable, and
our lessons should lead naturally from one to the other.
32. The Life Cycle of Plants. — The year is made up
of seasons, one following the other. As spring passes
imperceptibly into summer with nothing but an arbitrary
division between, so one period in the life cycle of a plant
passes imperceptibly into another. For convenience in
our study, we have divided the life of a plant into seven
periods, devoting to each period one chapter, or lesson.
These are as follows:
(1) The Seed: Its Selection and Distribution.
(2) Seed Germination. |
(3) The Work of Roots.
(4) The Work of Leaves.
(5) The Work of Stems.
(6) The Work of Flowers.
(7) The Formation and Development of Seed.
33. How the Parts of a Plant work together. — A seed |
is selected and stored away by man, or it is carried by the
wind or in the fur of some passing animal. Thus it is
planted in a well prepared seed bed or becomes covered in
44
THE ROUND OF PLANT LIFE 45
Nature’s own way. As the warm days of spring come
on:
The seed absorbs moisture and takes in oxygen. The
tiny plant within the seed begins to grow. It breaks the
seed coat and pushes its way further downward into the
soil and upward into the light.
“The roots search for food and
moisture in the soil as though they
had eyes.” |
The leaves are held up to the sun-
light; and by its help they manufac-
ture the food that nourishes not only
the plant itself, but man
and beast as well.
The stems develop
for the sole purpose of
fh A
Fig. 13. — Stages in the life of a bean.
\\
He
holding these leaves up to the light and conducting to
them minerals and water from the soil.
' Lastly the flowers appear, not for beauty, not for
fragrance, although we enjoy both. Flowers form seed.
Not all the seeds produced by a single flower or by a
single plant can develop on the same spot of ground.
They must be scattered by Nature or by man, and in
their new locations, they must begin just as the seed
which produced them began.
CHAPTER VII.
THE SEED: ITS SELECTION AND DISTRIBUTION
34. The Functions of the Seed.— Every part of a plant
has one or more duties to perform. The seed has three:
First: to protect the tiny plant, embryo or germ within
it.
Second: to assist in the work of distribution; that is,
to help to bring about its own removal from the parent
plant that it may find a favorable place in which to
germinate.
Third: to nourish the young plant within it until the
latter is able to gather and manufacture its own food.
35. How the Embryo is protected. — Kach seed has
its characteristic seedcoat, or covering. Sometimes it is
thick, shell-like and woody as in the case of the nuts;
sometimes it is thin, paper-like and almost waterproof
as in the bean and corn; again, the seedcoat may become
covered with layers of fiber, or lint as in the cotton. No
matter what the form and structure of a seedcoat may
be, it protects the embryo plant within against the enemies
outside. Among these enemies are moisture, heat, drouth,
insects, molds, and animals. The chief of these is mois-
ture.
36. How Seeds are scattered by Nature. — Seedcoats
not only protect the embryos within, but often assist the
seeds in becoming scattered. It is of the greatest impor-
tance to a plant family to have the seeds of each member
46
THE SEED: ITS SELECTION AND DISTRIBUTION 47
scattered away from the parent. Nature has provided
for this in many ways. The most important of these
ways are: (1) wind; (2) water; (8) animals; (4) explosive
or creeping habit of the seed pod.
Those seeds which are scattered by the wind have either
a feathery growth attached, like the dandelion, which
enables them to fly through the air, or they have a keel-
Fic. 14. — Seeds scattered by the wind.
shaped attachment, which, acting like a ship’s rudder,
turns the seed about in the air. The seeds in this last
group often whirl through the air as they fall from the
parent plant. The soft maple and the basswood are
excellent examples. Plants like the tumbling pigweed
and the Russian thistle, when mature, break off easily
from their roots and go bumping and tumbling along the
ground before the wind, scattering their seeds as they go.
Those seeds which are scattered by the water are usually
48 SOILS AND PLANT °LIFE
light enough to float. It is not easy for water to enter
seeds of this class, but many of them will grow even after
being water-soaked.
Those seeds that are scattered by animals may be
divided into three groups: (1) those which cling by means
of hooks or spines to the fur, hair or bodies of animals;
(2) those which have food stored within or around them,
Fic. 15.— Seeds scattered by animals. Note the Cockleburs in the
fur of the collie.
and which the birds and other animals carry some dis-
tance and drop; and (3) those which the animals eat
and which pass uninjured through the digestive tract.
Some seeds, as those of the squirting cucumber, are
thrown some distance from the parent plant by the pod,
itself, much as we snap a fresh cherry pit between our
thumb and finger. When the pods of some other plants
such as the yellow oxalis, become dry, they snap the seed
THE SEED: ITS SELECTION AND DISTRIBUTION 49
away, as we would a bean with a bent stick. Still other
seeds, such as those of the wild oat, actually work their
way along the ground in a sort of creeping motion.
37. How Seeds are scattered by Man. — Man has
played an important part in scattering seeds from state
to state and from one part of the world to another. Very
few of our noxious weeds are natives of America, most of
them having been introduced by
man from foreign lands. The
quack grass, the docks, the
Canada thistle, Russian thistle,
vigweed, foxtail and many others
were not found in this country
when the white man first began
to settle here. Man scatters seeds
of weeds (1) in commercial seeds,
(2) from railway and _ trolley
cars, (3) in wool and hay, (4) in
manure, and (5) in the packing
about goods and nursery stock. .
Many of the erains, OTasses, Fic. 16. — Explosive seeds :
trees and shrubs which grow iy fal ll as
in our fields and about our homes were first brought
to us from foreign countries. Of the following plants,
—corn, wheat, oats, red clover, alfalfa, timothy, blue grass,
cotton, apples, peaches, pears and oranges, — corn alone
originated on this continent. New varieties of seeds,
as well as those which have long grown here, are being in-
troduced each year from foreign countries. The annual
shipment of seed from state to state is enormous. The
shipper may fail to clean his seed properly. Commercial
seeds, therefore, become the carriers of weed seeds.
Almost every year, some new variety of plant springs
E
"50 SOILS AND PLANT LIFE
up along our railroads. The seeds have dropped out of —
leaky grain cars, or have been pushed out with the bedding
from stock cars.
Certain seeds, particularly those with hooks and spines,
become imbedded in the wool of sheep. When the wool
is shipped, the seeds go along and often germinate in the
waste piles at the mills. Hay, also, may act as a carrier
of seeds, either good or bad.
Stock is shipped from all parts of the country to our
large markets. More and more, the litter and manure
from the stockyards are being shipped to the country to be
scattered on the fields. Weed and other seeds often be-
come scattered in this way.
The roots of trees and shrubs must be packed in some
moist substance when they are shipped from place to
place. Chaff, straw, hay and moss are used. China,
glassware and crockery are usually packed in the same
materials to prevent breakage. In this packing are
often found small quantities of seed.
More weed seeds and seeds of foreign plants find their
way to our farms in commercial seeds than in any other
way. It is therefore of the greatest importance that we
examine any seed intended for planting lest such seeds
be mixed with seeds of weeds and other plants that we
do not want.
38. Making a Seed Collection.— We are at once
confronted with the difficulty of knowing the different
weed seeds.
Prepare a collection of the seeds of our common weeds,
which mature in the late summer and fall.
A small bottle, or vial, may be used to hold each sample,
and a case of heavy pasteboard or wood made to hold the
entire collection. Each bottle should be nwmbered; and
|
THE SEED: ITS SELECTION AND DISTRIBUTION 5l
on the inside of the cover of the case, a sheet of paper
should be pasted on which should be written the number
and name of each seed. The nature of the ground where
each plant was found should also be written on this
paper, the heading being as follows:
SEED No. NAME WHERE FouND
1 Cocklebur Cultivated Field
If neither you nor your teacher knows the name of any
given plant, — and none of us knows the names of all of
them — send both seed and plant to your agricultural
college or university, asking what the plant is. Very
shortly you will receive a letter giving its name.
Fic. 17. — A collection of seeds.
The method by which we determine the purity of a
seed sample will be made a part of our study of clovers.
52 SOILS AND PLANT LIFE
39. How Nature selects Seeds. — Nature carries on a
rigid seed selection. The strong seed produces a strong
plant which soon overshadows and crowds out its weaker
competitors. The seeds which produce plants that are
able to survive the heat and the cold, the drought or the
flood, the insect or the disease, are the ones which come to
make up the plant life of any locality.
The farmer destroys the weeds and other enemies
which retard the growth of the planted seed. The prob-
lem of careful selection and storage of the seed, however,
remains.
40. How Man selects Seeds. — As in the _ selection
of an animal, the selection of any seed should begin with
the parent. We want to know that the parent plant is
vigorous; that it is of a desirable type; that it is more
productive than the average of its kind, bearing fruit or
seed of high quality; that it is able to withstand the
ravages of insects, the attacks of diseases, and perhaps the
extremes of a variable climate; that its root system is
strong enough to hold it erect in times of high winds; and
so we might name many other things that man considers
in connection with the parent plant whose seeds he wishes
to sow in his fields.
In connection with any given species or variety of
plant, there are usually particular characteristics to con-
sider in addition to the general ones named above. More-
over, it should be understood that just as any given char-
acteristic may be regarded as highly desirable, so its
opposite, which may be found growing in the same field
or even beside it in the same hill or row, is just as highly
undesirable.
In the following exercise, you will select from the field
stalks of corn which show desirable characteristics and at
eT eee See SS eee eee ee ee =
es ae oe
on P »
ST ee ee ee ae hn Ba
et 7s os
THE SEED: ITS SELECTION AND DISTRIBUTION 53
the same time others which show the opposite, or undesir-
able characteristics.
EXERCISE 18
Object. — To study types of corn stalks, from which
seed ears may be chosen, and also types which are to be
avoided.
Procedure. — Select and bring to the school building
from any field you may choose fourteen or more stalks of
corn as directed below. Each of these stalks will show
either a desirable or an undesirable characteristic. Those
which are desirable appear first and in italics. Note
carefully the reasons given as to why the one is considered
desirable and the other undesirable.
(1) A strong, sturdy stalk of medium height and tapering
gradually to the top.
(1) A slender, spindling stalk with or without an ear.
It has been found that the best ears are commonly
borne on stalks of the first description. A really good
ear is rarely found on a slender, spindling stalk, no matter
how tall it may be.
(2) A stalk with an ear at medium height from the ground.
(2) A stalk with an ear borne either very low or very
high.
As a rule, the largest, best formed ears are not found
near the ground, nor high up on the stalk. Moreover,
both are hard to husk. Hence, seed ears are chosen from
those plants whose ears are borne at a medium height.
(3) A shank long enough to allow the ear to hang with
the tip downward.
(3) A shank so short that the ear is held with the tip
pointing upward.
If tip extends upward, rain may enter, water gather
at the base of the ear, and molds or decay result. This is
54 SOILS AND PLANT LIFE
undesirable in the parent plant, and would likewise be
undesirable in the offspring.
(4) A shank of medium size and strength.
(4) A shank too large and strong; or one that is small
and weak; or two stalks, each showing one of these faults.
If the shank is too large, the cob is also large, and the
proportion of corn to cob, 7.e., the shelling percentage, is
small. Also the ear will be held with tip upward, and it
will be hard to break off when husking. On the other
hand, if the shank is too small, the ear is liable to be broken
off by the fall winds.
(5) A stalk bearing an ear, whose husks are of medium
thickness and do not fit too closely.
(5) A stalk bearing an ear whose husks are too thick and
fit too closely ; or one bearing an ear whose husks are too
thin and loose; or better yet, secure a specimen of each
description.
If the husks are thick and close, the ear will dry out
slowly, maturing late; also it will be hard to husk. If
they are too thin and loose, the corn may be damaged
by the elements or otherwise.
(6) A stalk whose ear is well matured at the time when
the first killing frosts of autumn are about due.
(6) A stalk whose ear is wet, heavy and immature at this
time. 3
In most parts of the Corn Belt, early maturity is con-
sidered highly desirable as it lessens the danger of having
the crop injured when the fall frosts come. To this end,
seed is often selected in the field before the first frosts have
come in the fall. If well matured ears are chosen at that
time for seed, the crop raised from this seed should like-
wise mature early. In this way, the time required to
mature the crop has been gradually reduced by northern
growers with the result that corn is now raised successfully
THE SEED: ITS SELECTION AND DISTRIBUTION 55
far north of where it could have been grown even twenty-
five years ago.
(7) A stalk, bearing an ear whose tip is unexposed to the
weather.
(7) A stalk, the tip of whose ear is exposed to the
weather.
If the tip protrudes from among the husks, some kernels
are invariably damaged by the elements, smut, insects,
birds or otherwise. If such ears are used for seed, simi-
larly damaged corn may be expected in the resulting crop.
(8) A barren stalk; 7.e., one bearing no ear.
Barren stalks are found in every field. They occupy
space and receive care and attention without yielding
any return. Since they bear no ears, many people sup-
pose that they can not reproduce themselves. This is only
half true. The pollen from their tassels, which are really
the male flowers, falls upon the silks of near-by stalks,
fertilizing the kernels, which are a part of the female flowers.
Thus ears are formed containing the “ blood ”’ of the barren
plant; and if kernels from these ears are later used for
seed, they will have a tendency to produce barren plants.
Therefore in selecting seed ears in the field, the careful
grower rejects those found near a barren stalk..
(9) A stalk from whose base a sucker has grown.
A sucker is a stem, which branches from the main
stem of the plant near or below the surface of the ground.
It usually draws its nourishment from the plant which
bears it. As a rule, it bears no ear, or a mere nubbin,
while by draining the plant of nourishment, it weakens
the latter, reducing its productive power. Hence stalks
bearing suckers are considered undesirable. Many of the
best growers will not select a seed ear from such a plant;
nor will they choose an ear from any plant standing near
it, upon which its pollen might have fallen.
56 SOILS AND PLANT LIFE
Conclusion. — It is clearly evident from our study of
parent plants that no two plants are exactly alike. The
fact that they do vary slightly or radically enables a person
to select specimens which approach the ideal.
By the selection of seed, the sugar content of sugar
beets has been raised from twelve to more than eighteen
per cent.
By the selection of seed in America, the length of the
lint on Egyptian cotton has been almost doubled within
three years.
By selection of seed, the average number of rows on
an ear of corn has been raised from about thirteen to
twenty.
Moreover, by seed selection, the Corn Belt has been
pushed northward almost to the Canadian line, notwith-
standing the original home of the corn plant was in south-
ern Mexico.
Plants are improved and new varieties originated by
crossing one blossom with another. This is a delicate
and uncertain piece of work and requires the knowledge of
a specialist. Seed selection, on the other hand, is some-
thing that each one of us can do.
In the foregoing exercise have been given twelve
characteristics of the corn plant, which are undesirable
and which we should seek to avoid. Go over them care-
fully and state which ones could be avoided with certainty
by the farmer who selected his seed from the wagon or
crib in November.
41. Selecting Specimens for Corn Judging. — The com-
parison and judging of ears of corn will be left for our
lesson on that crop. Of course it is not enough that an
ear be borne on the right kind of stalk. It is necessary
that the ear, itself, and the kernels as well, possess certain
THE SEED: ITS SELECTION AND DISTRIBUTION 57
characteristics which are held to be desirable. Ifyou
think you are able to recognize good corn when you see it;
you may select now and store away for your judging later
in the year at least twenty good ears.
Bear in mind that a good ear of corn, —
(1) Should be perfectly sound and mature so that seed
from it is practically certain to grow.
(2) Is nearly cylindrical in shape, or very slightly taper-
ing, but rather “ full” in the middle.
(3) Has a butt well rounded, with kernels not too
square or blocky, and fitting closely around the shank.
(4) Has a tip well covered with kernels.
(5) Has straight rows free from depressions.
(6) Has kernels of uniform size and of keystone shape.
42. Nature stores no Seeds but provides for Loss. —
Nature has no granaries in which to store her supply of
seeds for another season’s crop. As we have seen, the
seeds are scattered far and wide. Those which escape
being devoured by the birds and other animals must pass
the winter in whatever place they chance to fall. Thus
exposed, many of them can not survive the extreme cold
of winter or the sudden changes of spring. The loss 1s
enormous, but Nature has provided for it by producing
an enormous quantity of seed. A single pigweed may
produce as many as fifty thousand seeds, while one Russian
thistle has been known to produce two hundred and fifty
thousand. One bushel of corn will plant about seven
acres, which in a good year should produce four hundred
bushels. This four hundred bushels in turn, you see,
would plant two thousand eight hundred acres. Thus
Nature’s habit of producing more seed than would be
needed for planting if properly stored, enables man and
58 SOILS AND PLANT LIFE
beast to live. The granaries and elevators overflowing
with oats and barley, the train loads of corn and wheat,
are Nature’s surplus.
43. Man’s Storage of Seed. — If the tiller of the soil
is to feed his animals, his own family and the great mass
of people who do not produce their own food, he
must carefully store that seed which he is to use for
planting.
Just how the seed should be made ready and stored
that its vitality may be preserved most effectually has
doubtless troubled the minds of men since they first be-
gan to cultivate the wild plants of the forest and prairie.
The principles of seed storage are by no means well un-
derstood even yet, though in recent years we have gained
much knowledge along this line.
In February of 1900, Mr. J. W. T. Duvel determined
to find out what influence the climate and duration of
storage under different conditions had upon the vitality
of seed. He selected apparently strong seed of the 1899
harvest, tested samples for vitality, placed clean, fresh
seed in manila paper seed envelopes, and sent two or more
packages of each kind to the following places :
Mobile, Alabama. Lake City, Florida.
San Juan, Porto Rico. Durham, New Hampshire.
Baton Rouge, Louisiana. Auburn; Alabama.
Wagoner, Oklahoma. Ann Arbor, Michigan.
The seeds arrived at each place about the middle of
February and were stored in an ordinary store room or
attic, which had little or no heat. Each sample contained
from one hundred to two hundred seeds. The following
kinds were sent: sweet corn, onion, cabbage, radish,
— Ss eee eS eee oe pro
=<
a ae eS SP
oe a eee ee
THE SEED: ITS SELECTION AND DISTRIBUTION 59
carrot, pea, bean, pansy, phlox, tomato, watermelon
and lettuce.
At the end of a little more than one hundred days, one
sample of each kind of seed was returned and tested for
vitality. Out of one hundred strong seeds of sweet corn
stored at Ann Arbor, Michigan, all germinated, while
only eighty out of one hundred stored at Mobile, Alabama,
germinated. A sample of weaker sweet corn showed only
48 per cent germination when stored at Mobile, and 92 per
cent at Ann Arbor. The average germination of all seeds
at the end of this period ranged from 53.59 per cent at
Mobile to 86.23 per cent at Ann Arbor.
At the end of about two hundred and fifty days, a second
sample of each kind of seed was returned from each place
and tested. The sample of one hundred strong sweet
corn seed from Ann Arbor all germinated except two seeds
while only twenty seeds of the sample stored at Mobile
did so. The weaker sample of sweet corn showed a ger-
mination of twelve per cent at Mobile and of 80 per cent
at Ann Arbor. By comparing this with the first test, we
see that strong seeds are less injured by an unfavorable
climate than are weak ones.
The onion seed had lost all of its vitality at Mobile at
the close of the second test, while at Ann Arbor, ninety-
seven out of every hundred seeds were capable of germina-
tion. The average germination of all seeds at the second
test ranged from 24.31 per cent for those stored at Mobile
to 84.58 per cent for those stored at Ann Arbor. The
average annual rainfall at Mobile is 91.18 inches, while at
Ann Arbor it is 28.58 inches. Do you see the connection
between moisture and the vitality of stored seed?
The table (p. 60), which is taken from a bulletin of the
United States Department of Agriculture, gives other
results of this interesting test.
60 SOILS AND PLANT LIFE >
0, 0
To | Aur E To 7 % oO
Atern | Ative | Siew | Ative | QUE) Auve| auive| 9%
WHEN wegen STORED ate Srorup| Srorep| WHEN | ALIVE
Rowe Oe Gaon POSED Sh TORED are ken STORED] WHEN
San * AT Dame ea Wac- | 47 San | Srorep
P a Baton us BURN ee aS JUAN, |AT ANN
MosiLe Rosen| a Ate City ONER | “p R. a
262 <\7, o47| Now| ‘ove’ | Pua. | 1. 8. is9” | BEL
Days ees 251 1¥ive 234 238 Daxg ;
Days Days | Days
Sweet corn)
(strong) 20:0 ->).,83:0'1 96.01 88:04 )/'92:0'>\. 90:05 4 9220 98.0
Sweet corn
(weak) 12.0. 54.22. 182.0." 162,00) 77.0) 1) 2820" 78.0 80.0
Onion! 0 0.5 O:0 F-20165 | 24 ae OF
Cabbage . | 17.0 Tapas 12.0 61.5 63.5 OLD 76.5 91.0
Radish’! 23-609) 5520 5 55).159 5) 63.0) <3) 5S e7 GOen see Tib
Carrot..5 0 | 851 25.0 ZO: i 30.0" 43> 4 Oa aes 86.0
Pea 0 a 4 44.0" 180.0 194.0. 11975! 48615*-| 80.01.9080 98.0
Bean ef 0.0-* 160208 “178.0 456.0 1:84.60. -] 82:02 96.0. ane
Parey? 6:36 Oe 010 0.0. 2A 1.5 i 6.5 46.5
Phlox drum-
mondii 0.0 0.0 0.5 1.0 2.5 ao i fe ee 40.0
Tomato . | 49.5 | 96.0 | 87:0 | 94.0.1 94.0 }94:0 -].96.5 98.0
Watermelon | 64.0 | 92.0 | 82.0 | 86.0 |.92.0 | 94.0 | 88.0 96.0
Lettuce 24 20:0 «84:51 88:5 © | 86104-8510 32.0 SP Saeb 92.5
Averages of
all seeds 24.31 | 50.86 | 52.42 | 57.34 | 61.27 | 62.11 | 68.21 | 84.58
Mr. Duvel summarized his careful work in twenty-
seven statements. Six of these are as follows, important
words being here put in italics :
“A seed is a living organism, and must be dealt with as
such if good results are expected when put under favorable
conditions for germination.”
“ The first factors determining the vitality of a seed are
maturity, weather conditions at the time of harvesting, and
methods of harvesting and curing.”
‘Seed harvested in damp, rainy weather is much weaker
in vitality than seed harvested under more favorable
conditions. Likewise, seed once injured will never regain
its full vigor.”
|
{
|
4
|
THE SEED: ITS SELECTION AND DISTRIBUTION 61
‘Experiments have shown that moisture is the chief
factor in determining the longevity of seeds as they are
commercially handled. Seeds stored in dry climates
retain their vitality much better than those stored in
places having a humid atmosphere.”’
“Seeds that are to be sent to countries having moist
climates should be put up m a?r-tight packages. Experi-
ments have shown that by the judicious use of bottles
and paraffined packages, seeds can be preserved practically
as well in one climate as in another.”
“The life of a seed is undoubtedly dependent on many
factors, but the one important factor governing the longev-
ity of good seed is dryness.”’
The application of these principles of seed storage will
be considered under our lessons on the different crops.
QUESTIONS
1. What are the functions of seeds?
2. Name four ways by which Nature scatters seeds. How
can you tell by looking at any given seeds how they will be
seattered ?
3. Name four ways by which man thoughtlessly scatters
seeds.
4. Name four common weeds of the cultivated fields; four
of the meadows; four of the lawns.
5. How does Nature carry on seed selections ?
6. Why should seeds of cultivated plants be selected as
far as possible in the fields?
7. How does Nature store her seeds? How does she provide
for loss? .
8. How do seeds stored in a moist place or climate compare
in germination with those stored where it is dry ?
9. What is the greatest enemy of stored seeds?
10. Name the three factors which at first —that is, at
harvest time — determine the vitality of the seed.
CHAPTER VIII
SEED GERMINATION
44. What a Seed is.— A seed is a very small, or embryo
plant, the germ, having food stored in or around it, by
which it is nourished until it is able to maintain an inde-
pendent growth. Both the germ and the stored food are
covered and protected by a seedcoat, into which they are
very tightly packed.
45. Two Great Classes of Plants. — The little plant
within the seed, called the embryo, or germ, consists of
three parts; viz., the leaf or leaves, which are called the
seed leaves, or cotyledons; the hypocotyl, or the part of the
tiny plant below the cotyledons, the lower end of which
is called the radicle; and the plumule, or the part above
the cotyledons.
Those plants which bear inclosed seeds, — and this
includes practically all common plants except evergreen
trees — are divided into two great classes. This classifi-
cation is based upon the number of seed leaves, or cotyle-
dons, in the embryo. If only one cotyledon is present,
the plant is known as a monocotyledon ; if two are present,
it is a dicotyledon. These two great classes of plants
differ not only in their embryos, but still more widely in
their stems and leaves, so that we are easily able to dis-
tinguish them at any stage of their existence. These
differences will be shown in later chapters.
The monocotyledons include the plants of the grass
62
:
iia
SEED GERMINATION 63
family, and hence all of our cereal crops, as corn, wheat,
rice, oats, barley and rye, for they are all grasses.
The dicotyledons include the clovers, beans, peas,
cotton, the common vegetables, = broad-leaved plants
generally.
When we ex-
amine the seed of
either of these two
classes of plants,
we are usually
easily able to
distinguish the
parts. We find
the embryo, or
germ, in the mono-
cotyledons at the
base of the seed,
as in the case of
corn, and having
but one cotyledon,
while the stored
food occupies a
= NN
large space outside
the embryo and Fic. 18.— Corn and bean showing parts; the
is called the endo- embryo of each removed.
sperm. In the a, cotyledons; b, plumules; c, hypocotyl, the
d eohe. ai lower end of which is called the radicle; d,
seeds 0 € l- endosperm.
cotyledons, there
is no endosperm, or food, stored on the outside of the
embryo. The food is contained in the cotyledons in-
stead, which accounts for their large size. They occupy
the entire space within the seedcoat, or hull, except
that taken up by the little plumule and hypocotyl.
Study carefully Figure 18, noting particularly the plumule
64 SOILS AND PLANT LIFE
and hypocotyl in each seed and where the food is stored
in each one.
EXERCISE 19
Object. — 'To study the parts of the seeds of the two
great classes of plants.
Procedure. — Soak a few beans and grains of corn for
an hour or more. Shave away the entire face of one of
the grains of corn on the germ side with a sharp knife.
When the plumule and hypocotyl are plainly visible, set
the kernel up where you can see eit easily and make a careful
drawing.
Open the halves of a bean, being careful not to break the
plumule and hypocotyl, which lie near the spot where the
bean was attached to the pod. Make a drawing of one
half of the bean, showing the parts in place.
Label all parts in both drawings.
Conclusions. — State fully in what respects the two
embryos are alike and in what respects they differ. Do
not fail to explain clearly where the food that is provided
for the little plant. after germination is stored in each seed.
46. The Conditions required for Seed Germination. —
When the right conditions surround a living, mature seed,
the embryo awakens, sprouts or, as we say, it germinates.
We are at once interested to know what these right condi-
tions are and how far it is within the power of the farmer
to provide them. Let us state and then prove that before
a living seed will germinate, it must have (1) oxygen,
(2) a proper amount of moisture, and (3) a proper tempera-
ture. .
EXERCISE 20
Object. —'To prove that a seed must have oxygen in
order to germinate.
Procedure. — Fill a jelly glass or a pint fruit jar half
4
b
SEED GERMINATION 65
full of fresh water. Fill another with water which has
been boiled for several minutes to drive cut the oxygen.
As soon as the boiled water has reached about the same
temperature as the other, drop a few seeds of rough rice
—1.e., rice as it comes from the fields, having the hulls
still on it —into each jar. Pour a few drops of machine
or other oil on the surface of the boiled water, to prevent
any oxygen from entering the water in this jar. Set the
two jars aside in a
warm place for a week
or more ; then observe
which seeds have made
the better growth.
Conclusions.—
Write briefly in your
own words what has
taken place in each
jar: Why . do. you
think the seeds in one
jar have made a better
growth than those in
the other?
Fic. 19.— Rice in boiled and unboiled
When we speak of water.
oxygen, we must think
of the air, for oxygen is a part of the air. (See Section 15.)
Review Exercises 10 and 11. Tell four ways by which
a farmer may make it possible for a generous supply of
oxygen to reach the planted seed. (See Section 17.)
47. Moisture and Germination.— There are a few
kinds of seed, which, like that of the rice, will germinate
under water; a few will germinate in the desert countries
with very little water; the majority of seeds, however,
germinate and make their best growth with a moderate
F
66 SOILS AND PLANT LIFE
amount of moisture. All seeds require some moisture
before they will germinate.
. EXERCISE 21
Object. — To show that seeds require moisture for
germination.
Procedure. — Fill.a narrow bread pan two _ thirds
full of water. Secure a piece of window glass at least
a third longer than the pan, but so narrow that one
end of it will drop into the pan while the other extends out
beyond. Cut a piece of blotting Pane the same size and
lay it upon the glass.
Moisten the following seeds slightly to make them stick
to the blotter; then lay them in rows lengthwise upon
it :
A row of rough rice.
A row of alfalfa seeds.
A row of Teparie beans.!
A row of wheat.
1 These little Teparie beans have a unique and interesting
history. They now form an important article of diet for many
of the Indians of Arizona and adjacent states where the rainfall
is only about nine inches per year. ‘‘Throughout a one thousand
mile circle of semi-arid and subtropical country are found the
seattered relics of prehistoric agricultural tribes. The ruins of
their houses and their ditches, their pottery, their implements of
stone, and sometimes their bones remain to us. But of greater
value and interest than any of these are the descendants of these
tribes, and some of the ancient crop plants which yet endure.”’
Teparie beans have come down to us from these ancient tribes.
The seed will germinate in a surprisingly short time; and the
plants will endure severe drouth and set seed in the hottest and
driest weather. They may lose every leaf; but with a passing
shower, they put forth leaves again and continue growth. They
are sure to occupy an important place in the agricultural develop-
ment of the semi-arid Southwest.
SEED GERMINATION 67
Put one end of the glass with the blotter and rows of
seeds in place into one end of the pan and let it sink be-
neath the water, while the other end extends out beyond
the other end of the pan. If any of the seeds float off
when you place the end of the glass in water, put them
back into place with your fingers. One end of each row
will now be under water while the other end will be out
in the air. Keep the water at the same height in the pan
each day.
a
THE WORK OF ROOTS 83
vation while the plant is young, and shallow cultivation
later, or shall we follow just the opposite plan? “ But,”
you say, ‘‘ how can we study the root systems of plants
when they are out of sight beneath the ground?” Let
us try to do it.
EXERCISE 27
Object. — To study the root systems of the corn and
bean.
Procedure. — Plant in a wire basket several kernels of
corn, and in another basket several beans. These baskets
should be at least six inches square, have the same depth,
and be made of very fine woven wire. Wrap a piece
of cheesecloth very carefully about each one to prevent
the dirt from sifting through the sides and bottoms, and .
fill them with fine garden soil.
When the seeds have sprouted well, remove all but
one of the strongest. When the corn plant is six or eight
inches high, remove the cheesecloth from this basket, and
also from the one containing the bean and thrust pieces of
rather fine wire through the sides of the basket and through
the soil. These wires will hold the roots in their natural
position when the soil is washed away. Now place each
basket in a pan or bucket of water and move it slowly
back and forth until all the soil falls away, leaving the
roots exposed.
If you have larger baskets, the roots may of course be
studied when the plants are older.
Conclusion. — You will find that the long, or temporary
root of the corn plant has withered or is withering away,
and in its stead, quite close to the base of the stem, a mass
of fine fibrous roots is developing. This mass of fibrous
roots is formed in all the cereals just beneath the surface
of the ground regardless of the depth at which the seed is
planted.
84 SOILS AND PLANT LIFE
In the dicotyledon, the bean, you will see that the first
root is a permanent one and grows downward rather deep -
into the soil. Bear in mind these characteristic root habits
when you come to study the cereals and legumes. The
roots of the clovers and alfalfa penetrate deep into the
subsoil, bringing up plant food which is left near the sur-
face when these crops are plowed under. The shallow-
rooted cereals and grasses which follow them are thus
benefited.
Draw in your notebooks the root systems of the corn
and the bean.
60. How Roots help dissolve Mineral Matter. — In
Section 7 we learned that certain mineral elements are
essential to the growth of any plant. These elements
are found in the soil, and it is a part of the work of roots,
by the excretion of acids, to help dissolve them.
EXERCISE 28
Object. — To show that roots give out, as well as take in.
Procedure. — Fill a small bottle almost full of water,
and add a few drops of ammonia water, or dissolve in it a
grain or two of ordinary lye. Drop a slip of pink litmus
paper into it, and its color will begin to change. In a
short time it will have become blue. This shows that the
solution is alkaline, for alkalies turn pink or red litmus
paper blue.
Now add a littie acid of any kind, — vinegar will do, —
and presently the slip of blue paper will begin to change in
color again, turning this time from blue to red. Finally,
its color will be about the same as it was at the beginning.
This shows that the solution is now acid, for acids turn
blue litmus paper red. We are able by this test to tell
whether any solution is acid or alkaline.
THE WORK OF ROOTS 85
Now empty the bottle, rinse thoroughly, and fill again
nearly full of water. Put into it a slip of litmus paper
which you have made blue as you did the one above.
Wash the dirt from the roots of a seedling plant and
lower them into the bottle of water. Fasten some paper
about the bottle to exclude the light from the roots.
About forty-eight hours later, examine the litmus paper
to see if its color has changed.
Conclusion. — Would you say that the roots must have
given off some acid into the water? How does the litmus
paper show this? Acids dissolve many minerals. What
is the use of this acid given off by the roots? Since roots
of different plants feed at different depths, why is the
rotation of crops beneficial ?
Write out how acids and how alkalies change the color
of litmus paper.
61. How Roots hold Plants Erect. — One of the im-
portant functions of the roots of a plant is to anchor it in
the place where it is to develop, that its leaves and stems
may be held upright in the air. Some plants have a much
- firmer grip on the soil than do others, and may for this
reason be called soil binders. Large areas of sandy soil
along Lake Michigan were in former years almost devoid
of vegetation. The shifting of the sands by the high
winds destroyed nearly all young plants before they could
become established: By the use of beach grass and
other grasses, the shifting of parts of this soil has been
stopped ; and the land that was formerly waste, is now of
use. The western wheat grass is much used by railroad
companies to bind embankments. Large tracts of land
on mountain sides have in the past been stripped of their
trees. The roots soon decayed, and great scars, gullies
and cafions were washed out, making the land worthless
86 SOILS AND PLANT LIFE
for a second crop of trees. If a few of the trees only had
been removed, this injury to the soil would have been
avoided.
Land that tends to wash may well be sown to some
perennial crop which does not require cultivation.
The grip that roots have on the soil is well shown by
the stump puller. The power required to pull even a small
plant from the soil is indeed surprising.
Fig. 27. — Denuded and gullied land. This was once pasture land.
EXERCISE 29
Object. — To demonstrate the hold which roots have in
the soil.
Procedure. — Secure a potted plant which has a well-
established root system and a tough stem. Fasten a
small wheel in the end of an upright stick, and pass a string
over it, forming a pulley. Wrap a piece of paper about
the stem of the plant and tie one end of the string firmly
THE WORK OF ROOTS 87
about it. Pass the string over the pulley, and tie a bottle
or other container on the end. Now put shot or sand into
the bottle, a little at a time, until weight enough has been
secured to pull the plant from the pot. - Weigh both shot
and bottle.
Conclusion. — Why is it that such rivers as the Ohio,
Mississippi and others
in the Central West
carry so much greater
quantities of mud at
present than in an
early day when the
land which they drain
was in native grasses
and timber? Why do
railroad companies
and land owners plant
willows along the
banks of encroaching
streams? From this
experiment, would
you say that the
roots of plants bind
the soil quite firmly
together ? Why does
Fic. 28.— Pulling up a plant by means
the government often He nilley. andi week
prohibit the cutting
of timber entirely off from hill and mountain sides on
public lands ?
62. The Root a Storehouse of Food. — Every plant
stores in its stems and roots certain amounts of reserve
food to be drawn upon in time of need. The members of
one great class of plants which live two years and are
88 SOILS AND PLANT LIFE
therefore called biennials spend one whole season in storing
food in their roots to be used the following season in
producing seed. The carrot, parsnip, beet, turnip, mangel
wurtzel and sugar beet are excellent examples of this class
of plants.
63. Benefits of Roots. — In performing the functions
for which Nature intended them, roots assist in a remark-
able way in maintaining a permanent agriculture :
They loosen the soil by their deep and ramifying growth.
They bind the soil and thus prevent washing and blow-
ing.
They offer a home for friendly bacteria, which are
known in certain cases to gather nitrogen from the air,
thus adding to the store of plant food in the soil.
They enrich the soil when they decay.
QUESTIONS
1. Name four functions of roots.
2. By what law do roots gather moisture from the soil ?
3. Under what conditions do roots lose moisture?
4, What two classes of roots do plants have? What is
the function of each?
5. Why does a cabbage wilt when transplanted? Why do
we protect newly planted vegetables from direct sunlight ?
6. Where does growth take place in a young root?
7. Compare the root systems of the corn and bean.
8. How do roots help dissolve mineral plant food ?
9. How can you prove that roots have a firm grip on the
10. Name four benefits of roots.
CHAPTER X
THE WORK OF LEAVES
CERTAIN plants reproduce themselves without seeds.
Some get along without stems. None of the important
higher plants, however, can exist without roots and leaves.
64. Functions and Uses of Leaves. — Leaves are of
use to man as food, for the shade which they afford, and
for beauty. These benefits are incidental, however, to
the three functions which Nature has given them to per-
form. These functions are:
First: to manufacture out of the water from the soil,
and the carbon dioxide from the air, starch for the plant.
This is known as photosynthesis.!
Second: to give off the surplus water taken in by the
roots. This is called transpiration.
Third: to act as a storehouse for food.
65. The Manufacture of Starch.— The phenomenon
of starchmaking takes place only in the green leaves and
green twigs of plants. Just how carbon dioxide, an
invisible gas existing in the air, can be made to unite
with water to form starch, liberating oxygen at the same
time, we can not say. Yet upon the fact that it does so
in the green leaves of plants, all life in the earth depends.
‘The term photosynthesis is derived from photo, meaning
light, and synthesis, the act of putting together. It means, then,
the act of putting together, or building up, by light. The
reaction is:
6 CO, +5H.O + Light = CeH1O; +6 O,
89
90 SOILS AND PLANT LIFE
66. The Green Leaf likened to a Mill. — The process
may be likened to the work in a mill where corn and oats,
we shall say, are ground together to make the “ grist.”
The water from the root corresponds to the corn; the car-
bon dioxide from the air, to the oats; the green leaf, to
the mill; the sun-
light to the en-
gine; and the
starch formed, to
the grist. If any
part is lacking,
no grist can be
produced.
EXERCISE 30
Object. — To
learn how and
when food is man-
ufactured in the
leaves.
Procedure.—
Place a few grains
of starch in a
saucer and cover with two or three teaspoonfuls of water.
Add a drop of tincture of iodine, and note that a blue-black
color appears. This is the test for the presence of starch.
Secure a potted plant, or use any growing plant in the
schoolyard. Provide several corks and pins, a small pan
of wood alcohol and some tincture of iodine. Place
slices of cork on opposite sides of a leaf and thrust a pin
through both to hold them snugly and firmly against the
leaf so that no sunlight can reach it where they are held
against its surface. The remainder of the leaf will be
exposed to the light. Prepare several leaves in this way.
Fic. 29. — The green leaf as a mill.
THE WORK OF LEAVES 91
Set the plant in the sunlight, and after it has been there
several hours, remove the leaves to which the corks are
attached. Remember that the exclusion of light from the
portions of these leaves between the corks has probably
put a stop to the work of starchmaking there.
Place the leaves of the plants in a dish of water and
boil them for about one minute to break down the tissues.
Transfer them to a bottle of alcohol. Cork tightly and
set away for a day or more. If this does not remove
the green coloring matter, transfer them to a dish of al-
cohol and boil them in it until the coloring matter is dis-
solved and the entire leaf is white. In this case, use the
utmost care that your alcohol does not boil over, take
fire and burn up your leaves.
Now put the leaves into some tincture of iodine, diluted
with water. Allow them to remain in this solution three
or four minutes. Remove and wash them with fresh
water and spread them out on clean sheets of paper.
Test fine pieces of potato, crushed corn and powdered
rice or wheat flour for starch. Tell how and where this
starch was manufactured.
Conclusion. — Describe fully the results secured with
the leaves and explain. If weeds, or other plants, cut. off
the sunlight from growing plants, what part of the ‘‘ mill ”’
indicated in Figure 29 is shut off? Why are plants which
are crowded often spindling in growth? Why do sprout-
ing potatoes in the cellar grow toward the light of the
window?
67. How Other Foods are made. — The starch, manu-
factured in the green leaves, is one of the chief food mate-
rials of the plant, but it is of the utmost importance for
still another reason. With starch as a basis, the plant
makes many other kinds of foods, such as sugars, fats,
92 SOILS AND PLANT LIFE
oils and proteins, using, when needed, those essential
elements which come to it in the soil water.
It is from the various food materials, made in this way,
that the plant derives the energy that makes its own growth
possible. It is from them that all of its t7sswes are built,
whether wood, bark, fiber, blossoms, fruits or grains.
Moreover, animals depend upon these food materials
made by the plant just as does the plant itself, for it is
from them that animals derive all of their heat and energy
and tissue-building material.
Thus we see that out of the raw materials — the ten
essential elements which come to them from the soil and
air — plants are able to make the food supply not only
for themselves, but for all animal life as well. That is
to say, while man may eat the flesh of animals, he may be
sure that these animals were in turn dependent upon
plants for their existence, or upon other animals, perhaps,
whose food supply was drawn from plants.
As the Father of Waters, the great Mississippi, may be
traced to its source in the highlands of Minnesota, so the
food supply of the world can be traced back to its source
in the green leaves of plants where carbon dioxide and
water, and minerals from the earth, by the power of the
sun, unite to form the food substances that make it possible
for plants and animals, including man himself, to live.
68. Amount of Water, Food Material and Ash in
Plants. — The weight lost by plants in drying repre-
sents the water held in the tissues. The weight lost in
burning represents the food manufactured in the leaves.
The ash remaining after burning contains all of the minerals
which come from the soil except the nitrogen, which escapes
unto the air in the process of burning.
THE WORK OF LEAVES 93
EXERCISE 31
Object. — To determine how much food is manufactured
in the leaves.
Procedure. — Cut into very fine pieces one hundred
grams of potato, grass, apple or any grain. Weigh
again after cutting to make sure that your original weights
are accurate. Set the pan or dish containing your material
on the back of the stove or in an oven. When perfectly
dry but not burned, weigh again.
Put the dried material into a dish which will withstand
heat, and carefully burn it over a hot fire. When nothing
but white ashes remains, take the final weight.
Conclusion. — How much water did the material which
you used contain? Where did it come from? Will it
get back to the soil again? If so, how? How much food
material and how much ash did the substance which
you used contain? Where did each come from? What
element came from the soil but escaped into the air?
Give two reasons why cornstalks and straw should not
be burned. (Sections 4 and 68.) How do your results
compare with those of others who used other material?
Why do grains produce more flesh and energy in animals
than the same weight of green forage, potatoes, beets or
other root crops?
69. The Water given off by Leaves. — ‘The minerals
which a plant takes in are really received in a very weak
solution. in other words, a great deal of water is ab-
sorbed to get a small amount of phosphorus, potassium
or any other element required from the soil. The excess
of water must escape, and it does so through the leaves.
On the under side of leaves, and to a limited extent on
the upper side also, are found numerous tiny openings,
called stomata. These stomata are guarded on either
94 SOILS AND PLANT LIFE
side by cells, known as guard cells. When there is more
than enough water to unite with the carbon dioxide to
form starch, and when the sun is shining, these cells draw
apart and allow the water in the leaf to escape and the
carbon dioxide to enter. This escape of water, which is
in the form of invisible vapor, through the stomata
of the leaves is called transpiration.
The roots of a plant must absorb from two hundred
and twenty-five to nine hundred and fifteen pounds of
water for every pound of dry matter, or food material
produced. In times of drouth, the stomata are partially
or nearly closed, so that transpiration becomes slower.
During the night, the stomata are closed, but the roots
absorb moisture in the darkness as well as during the day-
time. It follows that when moisture reaches the leaves
in the night, it can not escape, but accumulates both in
the leaves and back in the stem, making them turgid.
This explains why plants look fresh in the morning and
why corn will break under the cultivator in the early
morning but not at noon.
We are able by a very simple experiment to determine
how much water escapes from the leaves.
EXERCISE 32
Object. — 'To determine how much water the leaves of a
plant throw off.
Procedure. — Cover with melted paraffin the outside
and bottom of a flower pot containing a healthy plant.
Put a cork in one end of a glass tube and thrust the open
end into the soil in the pot. Cover the surface of the
soil with melted paraffin which has cooled enough to do
no injury to the stem of the plant.
Notice that no water can now escape from the soil in
the flower pot except by passing out through the plant;
THE WORK OF LEAVES 95
and since little or none escapes from the stems of plants,
we may say that that which is lost from the pot is given
off by the leaves.
Carefully weigh the flower pot and plant. Remove
the cork from the glass tube each day, pour water through
Vig. 30.— The water lost by leaves.
it into the soil, keeping an accurate record of the weight
of the water so added, and being careful to replace the
cork each time. At the end of a week, weigh the plant
and pot again, and from the figures which you will now
have, determine the amount of water given off by the
leaves during that time. Measure as accurately as
possible the number of square inches of leaf surface on the
plant.
96 SOILS AND PLANT LIFE
Conclusion. — Determine how many grams per square
inch the plant has given off during the week. Reduce it
to ounces, considering that twenty-eight and three tenths
grams are equal to one ounce.
How many tons of water will the velvet weeds in a
ten-acre field remove in one hundred days if each weed
throws off as much water per square inch of leaf surface
per day as the plant with which you have worked? The
average leaf surface on each weed is two hundred square
inches and the average number of weeds is two on each
square rod.
70: Storage of Food in the Leaves. — The food which
is manufactured in the leaves is used by the plant in three
ways:
First: to supply the: plant with energy with which to
carry on the processes of growth.
Second: to build the tisswes of which its body is com-
posed.
Third: It may be stored away for time of need, such as
drouth, dormant season, or to nourish the seedling after
germination.
We have already seen how roots may be used as store-
houses of food. Leaves, like those of the cabbage, or
those which make up such bulbs as the onion, become
filled with reserve food, and for this reason are useful to
man.
QUESTIONS
1. Give three functions of leaves.
2. Draw from memory a leaf considered as a mill, showing
how food is manufactured within it.
3. Tell briefly and clearly how you proved that a leaf
manufactures starch, and that sunlight is necessary.
4. Why will plants always reach for the light?
5. Name two reasons why starch is important,
THE WORK OF LEAVES 97
6. Where do the water, the food material, and the ash of a
plant come from?
7. How does water escape from the leaves?
8. Why will corn break under the cultivator in the early
morning but not at noon?
9. How ean you find out how much water a plant gives off?
10. State three ways in which the plant may use the food
which it manufactures.
CHAPTER XI
THE WORK OF STEMS
71. The Functions of Stems.— The three functions
which Nature has given stems to perform seem to be:
First: to hold the leaves up to the light that they may
manufacture food.
Second: to conduct the water and dissolved minerals
from the roots to the leaves.
Third: to conduct the food manufactured in the leaves
back again to the roots and other parts of the plant.
72. The Forms of Stems. — In the effort to hold their
leaves up to the light, stems grow in three fairly distinct
forms; (1) prostrate, or trailing, (2) climbing, and (3)
erect.
73. Prostrate Stems. — Plants which form this kind of
stems are often overshadowed by those with erect stems.
Notwithstanding this fact, a large number of plants have
prostrate stems. Such plants as the prostrate pigweed,
purslane, sweet potato and the dooryard weed, or knot-
weed all have this form of stem. Because of their clinging
closely to the ground, these plants require less moisture
than they would if the stems were higher in the air. The
stems themselves act as a mulch to prevent the escape of
moisture from the soil while often at the joints roots are
formed.
Even when these plants grow among the erect plants
as the purslane or crab grass grows among the corn, the
98
THE WORK OF STEMS 99
. prostrate stems creep, turn and twist to reach the beams
of light, which filter through between the blades. When
we remember the troubles we have had in hoeing these
weeds from our gardens or fields, we conclude that pros-
trate stems may get along very well in competition with
other kinds.
74. Climbing Stems.— Such plants as the morning
glory, the grape, and the five-leaved ivy, or Virginia
creeper, twine their stems around any support they can
find and thus raise their leaves up to the light. Plants
with this class of stems are excellent for covering over
trellises, arbors and fences which may screen buildings
and unsightly places. When some of these plants, such
as the wild morning glory and the black bindweed, grow
among our field crops, they become serious pests. Their
roots take from the soil, moisture and plant food needed
by the growing crop, and they interfere with the harvest-
ing of the crop as well. Moreover, their stems twine
about the stems of the corn and other plants, which
makes them extremely hard to destroy.
75. Erect Stems. — The great majority of plants have
this kind of stem. They may be short or long, depending
upon the environment in which they grow. On the plains
the grasses and prairie flowers have short stems, but they
are mostly erect. In the forest, the trees form stems of
remarkable length and strength, and because of this,
yield us our supply of lumber. Most of our cultivated
crops have erect stems. For this reason, we are able to
cultivate the ground close around them; the binder and
header can be used to harvest them; the mower can be
used to cut them down; and the stems themselves in ad-
dition to the leaves often make excellent forage. Those
100 SOILS AND PLANT LIFE
which are harvested or gathered by hand, as the cotton
and corn, are held up at a convenient height to pick.
76. Study of the Forms of Stems. — Nothing will
fix in our minds the habits and uses of stems so well as a
Fic. 31. — Cornstalks with an extra
burden.
field study and a col-
lection of them.
Gather at least three
specimens of plants
with prostrate stems,
three with climbing
stems and three with
erect stems. Record
in your notebook where
each was gathered, that
is, whether in pasture,
cultivated field, or-
chard, or elsewhere;
also, tell what chance
it had to get plenty of
light, and what is the
use of the plant to man.
EXERCISE 33
Object. —'To become
familiar with the char-
acter of stems.
Procedure.— Place
the stem of a mature corn plant, a mature, dry morning
glory vine and some prostrate plant, as the purslane or
the prostrate pigweed, on the table before you. Notice
the joints, or nodes, on the cornstalk; also that there are
joints on the other stems, though they are different in
appearance from those of the corn plant.
THE WORK OF STEMS 101
Conclusion. — Where do the leaves grow out from the
stems of each of the plants? Are the leaves of the corn
plant arranged on opposite sides of the stem, or are they
arranged spirally? How are they arranged on the morn-
ing glory? Of the three kinds of stems, which would
need to be most rigid? Why? Do you find it so?
Which would need the strongest anchorage roots? Why?
Name three cultivated plants with erect stems, three with
climbing stems and two with prostrate stems. In what
kind of fields is each grown, and how is it cared for?
77. How Water travels from Roots to Leaves. — We
have seen how the roots draw water, containing dissolved
mineral substances, from the soil. We have learned the
uses to which this water is put in the leaves. How does
it pass upward from the roots to the leaves?
In every plant, extending continuously from the ends
of the roots to the leaves, are tiny tubes, which are more
or less connected. These are the water-carrying vessels,
and united with them are the food-carrying cells which we
shall study shortly. The two are joined in such a way as
to form strands, or threads, called fibro-vascular bundles.
We noted in Section 45 that the common plants are
divided into two classes, the monocotyledons and the
dicotyledons. . The stems of these two classes are very
different. In the monocotyledons the bundles described
above are scattered irregularly, either through the pith
as in the cornstalk, or through the walls of the hollow
stems, while in the dicotyledons, they are regularly
arranged in a circle or circles about the central pith.
EXERCISE 34
Object. — To study how the water travels irom the
roots to the leaves.
102 SOILS AND PLANT LIFE
Procedure. — Wash the dirt from the roots of a corn
plant and of a bean plant, each about six or eight inches
high. Put the two plants in a glass of water containing
a few drops of red ink. After an hour remove them, and
with a razor blade cut each plant off at the lower end of
the stem. Make a thin section of the stem at this point,
and examine it with a hand lens to see where the water
has moved upward. Keep cutting thin cross sections
up the stem until you reach the point where only the
water-carrying tubes are stained.
A common house plant, the Sultana, has a very clear
stem, and the colored water may be watched as it moves
upward through it. Either the narcissus, or the Chinese
sacred lily, which you have probably grown in water in
the schoolroom, may have
its blossoms colored by add-
ing dye or ink to the water
= in which it stands.
Z - is T if afl Conclusion. — Describe
me ia al Hs ‘ briefly how the water-carry-
at ing tubes differ in arrange-
ment in the corn and bean
plants.
78. How to tell the Age
Hin: sip So aa aes of a Tree. — In the spring,
when there is an abundance
of water, the water-carrying tubes are very large. As the
season advances and the rainfall becomes less, smaller and
smaller tubes are made, until in the fall they are so small
and compact that they look like a ring of denser, harder
wood. In trees, therefore, which grow from year to year,
this circular line between the small water-carrying tubes
of the fall and the large ones of the spring is so plain that
THE WORK OF STEMS 103
we are able to tell the age of the tree, limb or twig by
counting the rings in its cross section.
79. How Food travels from Leaves to Roots. — The
food made in the leaves has three uses. (Section 70.)
In order that it may be used in any of these ways, it must
first be conducted from the leaves to the different parts
of the plant. We have already learned that it takes
several hundred pounds of water to produce one pound of
dry matter or food material in the plant. (Section 69.)
It is evident, then, that the vessels through which the
manufactured food travels from the leaves to other parts
of the plant need not be so large as those by which the soil
water travels from the earth to the leaves. The tubes,
called sieve tubes, which carry the manufactured food to
different parts of the plant, are very small indeed; and
no careful study.can be made of them without specially
prepared material and a compound microscope. It is
enough for us here to know that in the dicotyledons, these
sieve tubes are outside of the water-carrying vessels just
beneath the bark; while in the monocotyledons, they
are connected with the water-carrying vessels, forming the
fibro-vascular bundles, as explained in Section 77. These
bundles, which are seen as threads, running through the
pith of the cornstalk, have the double function, then, of
carrying water from the soil to the leaves, and manufac-
tured food from the leaves back to other parts of the plant.
You have perhaps noticed that where a notch has been
cut in a tree, a callus is formed above, but not below, the
cut. This means that the food on its downward path has
found a place where the ‘‘ bridge is out ’’ and has piled up
on the bank on the side from which it has come. Girdling
a tree is simply the cutting away of the bark and the sieve
tubes just beneath it. This stops the current of food and
104 SOILS AND PLANT LIFE
starves the roots.
©
3
252 SOILS AND PLANT LIFE
188. How Acid Soil affects Clovers. — Under the sys-
tem of farming generally practiced in the United States,
the soil gradually becomes acid, or sour. We can not,
of course, perceive this change in the soil with our senses ;
and since it comes so slowly, and its effect on cereal crops
is not readily seen, it may remain unsuspected for a
considerable time, sometimes even for several years.
The clovers generally are singularly sensitive to this
acid condition of the soil; and often the first indication.
we have of it is their feeble and uncertain growth in
fields where it seems that they should thrive.
The truth is that it is ampossible to grow red clover,
sweet clover, alfalfa, or certain other legumes success-
fully in an acid soil. How long they can survive in it
even depends chiefly upon how strongly acid the soil
may be. Thus if the acidity is only very slight, the young
clover plants may be only somewhat weakened, rather
than killed; and the crop may even mature, though the
growth will not be vigorous. If, however, a little more
acid is present, the little plants will grow still more weakly ;
and because of this weakened state, they readily suecumb
to unfavorable climatic conditions, such as drouth, or
perhaps extreme cold, later, in which case the failure is
commonly attributed to drouth or winterkilling as the
sole cause. It is merely a matter, then, of the degree of
acidity as to what the effect upon the clovers will be;
and if the soil is strongly acid, we find, just as we should
expect, that the little plants usually die soon after the
germination of the seed.
It is not at all difficult to detect acidity in the soil.
If a slip of blue litmus paper, such as we used in Exer-
cise 28, is placed in a cup of acid soil which has been
made wet with soft water, it will gradually change in
color, becoming tinged with pink. Let us make some
CLOVERS AND OTHER LEGUMES 293
tests of this kind and learn if there is any acid soil in the
fields near by.
EXERCISE 49
Object. — To ascertain if the soils in our fields at home
or in other fields near the schoolhouse are acid.
Procedure. — Bring to the schoolhouse, wrapped in a
clean paper, about a pint of soil from a field at home.
If it is taken from one in which clover has frequently
failed, so much the better. This soil should not be taken
up or handled with the hands, but with a small paddle
or shovel instead. Since other members of the class
will also bring samples, there will be a number to be
tested for acidity, and they should be marked or numbered
to prevent their becoming confused.
Procure, if possible, as many clean cups, glasses or
cans as you have samples of soil. Put a sample into
each cup, filling it about three-fourths full. Then add
soft water while you stir it with a small stick until a stiff
mud has been formed.
Now open a slit in this mud with a knife blade, insert
a slip of blue litmus paper, and close the wet soil against
the paper tightly with the fingers. Insert the litmus
slips in the other samples in the same way. Allow them
to remain in the wet soil for about an hour; then remove
the slips, dip them in soft water to rinse off the dirt,
and note the color of each one.
If any given slip is still blue, the soil is not acid; if
it is very faintly pink, you will know that the soil is
slightly acid; and if it is distinctly pink, the soil is strongly
acid.
Conclusion. — Write in your notebook the results of
the test of each sample, stating first: the field from which
it came and then its condition as shown by the litmus
paper.
254 SOILS AND PLANT LIFE
In making a litmus paper test to ascertain whether
clover will probably grow in a given field, we do not
usually follow the above method since it is necessary to
make many tests in different parts of the field. This
is due to the fact that the soil may be acid in some places
but not so in others.
The test of an entire field may be made in this manner :
Go into the field after a rather light rain while the
soil is in the form of a st¢ff mud about like putty. If
the test is made after a heavy rain, some of the acids
may have been washed out of the soil, and this will in-
terfere temporarily with the test.
Beginning at some point in one corner of the field, cut
a slit in the soil with a knife blade and insert a slip of
blue litmus paper to a depth of from one to three inches,
pressing the wet soil firmly against it. Repeat this
process at other points about ten rods apart each way
all over the field, marking each place by a stake.
After an hour or more, go over the field again, carry-
ing a small pail of soft water, in which to rinse the slips
of paper as they are dug from the ground.
Since some parts of the field are liable to be more
strongly acid than others, it is better to carry a plat of
the field, showing the location of each test, and to record
the results on it as the slips are dug up and examined.
It is important to have this information when we get
ready to correct this acidity in the soil by the method
which we shall shortly learn.
It should be understood that soil acidity may or may
not extend to the subsoil below.
189. How a Lack of Phosphorus affects Clovers. —
In many parts of the eastern states, as well as in some
sections of the Middle West, the soil is deficient in phos-
CLOVERS AND OTHER LEGUMES 20D
phorus. Moreover, in practically all parts of the United
States which are given over chiefly to grain and stock
farming, the supply of phosphorus in the soil is being
gradually reduced.
Just as clovers will not succeed in an acid soil, so they
will not thrive in a soil deficient in phosphorus. When
any given farm or agricultural section has reached the
stage at which phosphorus is lacking in the soil the suc-
cessful growing of clovers has because of this fact become
impossible until this element of plant food is restored in
some form to the soil whether as barnyard manure or
commercial fertilizers.
190. How a Lack of Humus affects Clovers. — Con-
trary to the popular belief, legumes, and _ particularly
clovers, with the exception of sweet clover, are not crops for
soils lacking in organic matter. It is a difficult task to
get clover established on such soils; and good farmers
often tell us to add manure or otherwise increase the
humus content of the ground before sowing clover or
alfalfa. :
A motto which might well be painted on the grain
drill is, “‘ Legumes are to be used on this farm to main-
tain fertility, not as a remedy for abused or ill-treated
soil.”’
191. How Absence of Friendly Bacteria affects the
Clovers. — The cardinal virtue of the legumes is that
they leave more nitrogen in the soil than they find. This
they can not do, however, unless the necessary friendly
bacteria make their homes in the root nodules as explained
in Section 180.
Unless the soil already contains the particular kind
of bacteria needed by a given legume, the bacteria must
256 SOILS AND PLANT LIFE
be placed in the ground by the farmer before the legume
can be successfully grown. This is known as inoculation.
192. How the Nurse Crop may affect Clovers. — We
should keep in mind the fact that clovers are commonly
sown in the rotation with a small grain, after the removal
of which they take possession of the ground as stated in
Section 140. This nurse crop of small grain is not, as its
name might be taken to indicate, a help to the young
clover plants, but is often very much a hindrance instead.
While there are many good reasons for this practice,
it is still true that it is open to some serious objections.
Thus we have found that the small grains, which are
shallow-rooted, demand a seed bed that is firm and com-
pact save near the surface. This is not true of the clovers
generally, since, owing to their long tap roots, a seed bed
that is loose and mellow to considerable depth is better
suited to their needs.
Aside from this, it is known that if oats are used as a
nurse crop, as is frequently the case, they almost com-
pletely exclude the sunlight from the young clover plants,
making healthy, vigorous growth impossible, and moreover
they take nearly all the moisture and available plant
food from the seed bed. It follows that when the nurse
crop is finally harvested and the delicate plants, which
have made top growth at the expense of root growth, are
suddenly exposed, without a proper supply of moisture,
to the direct rays of the hot midsummer sun, they must
suffer severely if, indeed, they do not succumb.
The same result must follow in case any other small
grain is used as a nurse crop if the stand is too dense.
193. How the Method of Seeding may affect Clovers. —
It is a rather common practice to sow clover seed on the
surface of the ground and to harrow or to disc it in.
CLOVERS AND OTHER LEGUMES 2o¢
The inevitable result is that some of the seeds are covered
very deeply while others are hardly covered at all.
Some, of course, will be covered to a proper depth,
and these may be expected to grow normally. Not so,
however, with the others. The seeds which are on or
very near the surface usually fail to germinate because
of lack of moisture, while those which are too deeply
covered fail to reach the surface because of an insufficient
store of food in the small seeds.
194. How Drouth may affect Young Clovers. Just
how hardy the normal, healthy young clover plant really
is as regards its ability to endure drouth and the heat
of the sun in midsummer, — or even the severe freezing
of winter —is an important question that has not been
satisfactorily settled. Many regard the little clover
plants as exceptionally weak and delicate, and hence
unable to withstand such adverse conditions as those
named. Others maintain, and with a show of reason,
that the young clover is in truth sufficiently hardy to
survive and establish itself under these severe conditions
if other conditions are right; 7.e., if the seed has been
properly sown in a soil which is not acid, which contains
enough humus and enough phosphorus to permit healthy
erowth, and which contains the particular kind of bacteria
that are necessary to the development of the plant.
While we can not say that the loss of young clover
from drouth or other unfavorable weather condition is
actually preventable simply by making other conditions
right, it is unquestionably true that such losses may be
largely prevented in this way, especially in those sections
where drouths are of comparatively short duration.
Losses may be ascribed to unfavorable weather con-
ditions only after all other conditions have been made favorable.
S
258 SOILS AND PLANT LIFE
195. How to succeed with Clovers. — The farmer who
would succeed in growing these virtuous crops, which
maintain the fertility of his lands and at the same time
yield nutritious forage for his animals, must see to it
that the causes of failure are, in so far as it is within his
power to do so, removed. It follows that :
(1) If the soil is acid, the acidity must be corrected.
(2) If it is deficient in phosphorus or humus, these
must be added to it.
(3) If the necessary bacterra are absent from the soil,
it must be znoculated.
(4) A suitable nurse crop must be used.
(5) The seed must be planted at the proper depth in a
well-prepared seed bed and uniformly covered.
Fic. 114. — Applying limestone to the land.
196. How to correct an Acid Soil. — An acid soil
may be corrected by the addition of crushed limestone
to it.
This is one of the most abundant rocks found in Nature.
It is used not only for making lime, but very commonly
for foundations of houses, cellar walls, ete.
When this rock is used to correct the acidity of the soil,
at least half of it should be in the form of fine powder, or
CLOVERS AND OTHER LEGUMES 259
dust. It may be applied with a special machine made
for this purpose, or with a manure spreader, the crushed
stone being put on top of a layer of manure.
If the soil is only slightly acid, from two to three tons
per acre are applied ; if it is strongly acid, the application
should be increased to five or six tons, or even more, as
no harm results from using more than is necessary. The
only reliable way to determine the amount required is
to make trial of the different rates of application. It
should be disced or harrowed into the surface soil but not
plowed under.
If crushed limestone can not be procured, lime of any
kind may be used. In such case, the application may be
not more than half as great as if limestone were used ;
and, except in the case of air slaked lime, it should not
be allowed to come into contact with plants, as injury may
result.
197. How to add Humus and Phosphorus to the Soil. —
In soils that have long been cultivated without a careful
system of rotation, humus is deficient; and unless phos-
phorus has been applied to the soil, it is probably lacking
also. Humus may be added to the land by plowing under
green crops; or both humus and phosphorus may be
added to it by the application of barnyard manure. If the
latter is used, it is advisable to apply with it pulverized
rock phosphate, or floats.
At least ten tons of manure should be applied to each acre
and not less than five hundred pounds per acre of floats.
198. How Bacteria are added to the Soil. — The soil
from a field in which any clover is established and thriving,
contains very many of the bacteria which are necessary
to that crop.
260 SOILS AND PLANT LIFE
By taking some of the soil found in such a field at a
depth of from two to six inches and scattering it uniformly
at the rate of about three hundred pounds per acre over
another field in which we wish to raise the same crop, we
may easily introduce the bacteria needed by the clover
that we expect to grow.
Since these bacteria die quickly when exposed to direct
sunlight, it is necessary to scatter the soil containing them
on a cloudy day or in the evening, and it should be har-
rowed or disced in immediately.
This inoculation is not necessary as a rule in growing
certain clovers because the particular bacteria needed
are already in the soil. However, in the case of alfalfa
east of the Missouri River, it is very frequently a matter
of the utmost importance.
199. The most Suitable Nurse Crops for Clovers. —
As was shown in Section 192, oats are a a suitable nurse
_ erop for clovers.
Winter wheat and rye are perhaps the most desirable
small grain crops to use for this purpose since they do
not wholly exclude the sunlight and are removed from the
ground early in the season. Spring wheat and _ barley
are more objectionable, but these crops are still to be
preferred to oats.
The rate of seeding of the nurse crop should not be in any
case more than two thirds of what it would be if the
clover were not sown; and it is better yet if only a half
the usual amount of seed is used, as the thinner stand will
admit more sunlight to the young clover plants.
If it is found necessary to use oats as a nurse crop, the
stand should not only be very thin, but the oats should
be cut for hay as soon as the kernels are in the milk
stage.
CLOVERS AND OTHER LEGUMES 261
200. How the Seed should be planted.— The seed
bed in which clover is to be sown should be disced and
harrowed repeatedly until the surface soil is finely pul-
verized. It is a serious mistake to sow clover seed in
cornstalk ground, which has been disced but once, or
even twice, if it has been left in a rough and cloddy
condition.
It is apparent that the seed should not only be planted
at a proper depth but at a uniform depth as well. This
can be accomplished only by means of the drill. As in the
case of other seeds, clover seed should be planted as
shallow as the conditions which govern germination will
permit.
201. Seed Selection and Analysis. — Before we take
up a more or less detailed study of how to grow the various
legumes, let us consider briefly the importance of seed
selection and analysis.
Comparatively few of the many noxious weeds which
infest our grain fields, meadows and pastures, are natives
of America. Instead they have come into our country
for the most part in agricultural seeds, as explained in
Section 37.
State and national laws require certain standards of
purity, that is, it is required that not more than a given
percentage of certain specified weed seeds may be present
in agricultural seeds sold within the state.
Just how pure a sample of seeds is in this respect may
be determined in a very simple manner, the process being
known as seed analysis. This work may be done at home.
It avoids the necessity of sending seed away to be ex-
amined, and often detects impurities which might not
otherwise be brought to the attention of farmers or of
the authorities,
262 SOILS AND PLANT LIFE
EXERCISE 50
Object. — To determine the percentage of good seeds,
of weed seeds, and of other impurities in a sample of clover
or alfalfa seed.
Procedure. — Procure a handful of seed from the top
of a sack or other large sample of clover or alfalfa seed,
another from the middle of the sack, and still another
Fig. 115. — Detecting the weed seeds.
from the bottom. Mix the three handfuls thoroughly
and then dip out a rounding teaspoonful. Spread this
out on a sheet of white paper, and with the aid of a hand
lens, separate the good seed into one pile and the impuri-
ties into another. Now separate the weed seeds, each
kind being placed in a small pile, and the shriveled clover
seed, the dirt and the chaff together in another pile.
Identify each kind of weed seed, referring if necessary
_—
CLOVERS AND OTHER LEGUMES 263
to, your collection made as required in Section 38; or the
illustrations in Figure 116 may help you in this work.
By referring to the table which follows, you can de-
termine the percentage of each particular weed seed in
your sample. For example, suppose you find thirty seeds
Fic. 116. — Seeds of some of the common weeds (many times en-
larged).
1, Bracted plantain; 2, black seeded plantain; 3, rag weed; 4, Ox-
eye daisy; 5, red clover; 6, catmint; 7, crab grass; 8, field dodder ;
9, sorrel; 10, dog fennel; 11, chickweed; 12, lamb’s quarter; 13, green
foxtail; 14, prickly sida; 15, vervain; 16, madder; 17, yellow foxtail ;
18, clover dodder; 19, heal-all; 20, yellow trefoil; 21, spurge ; 22, curled
dock; 23, lady’s thumb; 24 and 29, buckhorn, showing two faces; 23,
mustard; 26, alsike; 27, ox-tongue; 28, pigweed; 29, buckhorn; 30,
Canada thistle: 31, campion; 32, wild geranium; 33, peppergrass ; 34,
camomile; 35, mallow.
of buckhorn. According to the table, fifty-seven seeds
of this weed make one per cent of a teaspoonful of clover
or alfalfa seed. Therefore you have thirty fifty-sevenths,
or .526 of one per cent of buckhorn in your sample. I
any particular weed seed found in your sample does not
264. SOILS AND PLANT LIFE
appear in the table, compare it with one as nearly the
same size as possible, estimating the number that should
be equal to one per cent.
Determine in this way the percentage of each kind of
weed seed, and estimate the percentage of dirt and chaff.
It is necessary next to make a germination test of the
sample. Procure two pie plates or dinner plates and a piece
of clean, boiled muslin four or five inches wide and about
eighteen inches long. Dip the muslin in water and wring
it out. Then double it once, lay one end in one of the
plates, scatter one hundred average seeds on it, fold over
the muslin again so as to cover the seeds. Lay the other
plate upside down on this one. The muslin should not
protrude from between them; and they should fit as
closely as possible so that little moisture will escape.
The plates should now be set away while the seeds
germinate. However, the upper one should be lifted off
every day or two to make sure that the muslin has not
become dry. If it has done so, add water drop by drop
until it is well moistened but not saturated.
At the end of a week, open the cloth and examine the
seeds. You will doubtless find that most of them have
germinated, but that some which look perfectly sound and
good have not done so, while still others are shriveled or
discolored, showing that they are incapable of germina-
tion. The second class, those which appear good but have
not germinated, are known as hard seeds. It is generally
considered that one half of them would probably ger-
minate in the soil, but that the remainder would not do
so. In determining, then, the percentage of germinable,
or viable, seeds, we count those that have actually ger-
minated and add to this number one half of the hard seeds,
and the remaining seeds are regarded as non-germinable.
Conclusion. — Make a copy of the following form in
CLOVERS AND OTHER LEGUMES 265
your notebook and place there a record of the analysis of
your sample by substituting the right names and numbers :
Record of Seed Analysis
Kind of seed Red Clover
SecnrecwinOms lee dee a eee sy) dORn Jones
Percemiaaea: pure seed. <0 ait. bes a a ae eo, 9D.25F
Percentage Of weed seeds. Sie. ee a> a es ce | OSS
Percentage of dirt and inert matter . . .. . . 1.630
Weed seed present :
Buckhorn Rehan eeu she Mary te: fete 2 0.526
ELE COOK Ysa agin Page ae pa tee. 1:3
Geen tac Coe) be utcedndt Siar ecarer hoa aN 0:2
IRB MEREIAGS. cree amis Meee ye eer A ca Oi 0.05
Higmsialnut oeite veo Get Shoe ha bee cc ts 1.054
EAD PAG eae ogee need TRE BL 0.003
MCAS AIA st) eo en at nas hep 3.1383
Pereentace of vermmmnable seedsic aca S56 ad atin be Ca GL
Percentage of non-germinable seeds . . . . . ae at hoe
Date of Analysis Wiuu1amM Brown, Analyst.
202. Table of Weed Seed Weights.—In the first
column of numbers below is given the number of seeds of
each of the common weeds, required to make one per cent
of a rounded teaspoonful of clover or alfalfa seed; in the
second column are the numbers of seeds of the respective
weeds required to make one per cent of a sample of the
same size of timothy or millet seed:
NESS 03) OSE 8 IR em a ati, ea a aad a 5 4
SUMER GIO ATTA OG 2 sl tomer arcs Nee aE saa ene, a ieee 16
Tumbleweed piper EAs ele ott Racca, Bh eI 619 110
Srimeibaneewveeds. \ Rie alee es eae Ue 20) 16
Wiel THGISEAE 15.02 bona eaLee when inte Cea al, Oe 19
ele: HiuStATe): seas oda Re Gath aes oe Oe 48
MATONISOUATLCE gs is odsa. gt Ate atee Aaa ees a wh oe BT
Sraniats GIStIE: | ai". 2 Sk ope cere tel, chro kh AS 36
NUBILE RDG) a0) fae ea, iis 2k Nae NA A mR RAM GT: 50
Smooth crab grass Gy pen ar th eR eRe A gah) LO 155
266 SOILS AND PLANT LIFE
Kora erags? 12 Coa an Seeley be eet ae dea al Soe 142
Barnyard grass Sia ree ae tc itia tae aera een atta a ts Oke 48
Morning ‘clory iia a0 etc eee hee ohn 2 1.6
PEPPeTOrass) spe re ees ei eetres ee Ne eae eal 100
AGING ST AGS: AN Ei OF ails aah be eee epee ates Eile ay 100
Bractedhplantain 9 /iac mectestcer en Sree hl 28
Buckhorn ao ned ow ae OEM EC re nitty bm Ah 157) 46
PG ANL Sys ert ts eS es A ee eal 89
Black ‘bimdweed sls 5 eyo Ae oe ie la 9
Pennsylvania smarvweed. ov ys. ace Ae, ve ee 8
DHEep. SORPEN 1.05% aR stalaat ee Die a a etek ieee CD 8
Gurled. docks so.22 9 aah PA ae ean mee) ce aan 29
Fussian: thistle: wseeawee i) a aout ee halen say 53
"Yellow iomtaal o/s tater Sic Poh Oe i rete eet a ae 32
Green Foxtalle<.") Tesi! koe a Sire ee an ee aS 52
Vi Te 9S Fo te ae haa coe wp We oa ee a 20!
203. Methods of Culture of Legumes. — Red Clover. —
Most of the soils of the Corn Belt where red clover has
been long and successfully grown contain the bacteria re-
quired by it so that inoculation is not often necessary.
Aside from this, all the requirements named in Section 195
must be most carefully complied with if one would grow
this legume successfully. Acidity of the soil, the supply
of phosphorus, the methods of seeding and the use of a
suitable nurse crop are matters requiring special attention.
Most of the red clover grown in the United States is
mixed with timothy. It is advisable, however, that the
clover seed be sown in the spring while the timothy is
often sown in the fall. If mixed in this way, about six
pounds of clover seed and ten pounds of timothy per acre
are used. The growth the first season after the nurse
crop is harvested is good — and it is mostly clover. The
second year, however, the growth should be heavy with
timothy predominating. Two cuttings of hay are usually
1 This table is taken from Dr. L. H. Pammel’s excellent book, ‘‘ Weeds
of the Farm and Garden.” It also appears in Iowa Bulletin 115.
CLOVERS AND OTHER LEGUMES 267
secured, after which, if the timothy is not greatly desired,
and a regular rotation is being practiced, the ground is
prepared for corn the following year.
If red clover is grown alone, about ten pounds of seed
per acre are used. The second season, a cutting of hay
may be taken off in early summer, and the succeeding
growth of clover may be cut for hay, allowed to form seed,
Courtesy Iowa State College.
Fig. 117. — Making alfalfa hay.
or be plowed under. Since the plant is a biennial, it dies in
the fall of the second year.
Alfalfa. — There is no requirement named in Section
195 that may be safely disregarded in growing alfalfa east
of the Missouri River. Furthermore it is necessary that
the land be perfectly drained and that the weeds be kept
in check.
West of the Missouri, it is only rarely that soil acidity
is found or that the land is lacking in phosphorus. More-
over, the soil usually contains those bacteria which alfalfa
requires so that inoculation is generally unnecessary.
268 SOILS AND PLANT LIFE
In the older states, inoculation is a highly important
matter as a rule. Soil for this purpose may be procured
either from another alfalfa field, or from a field of sweet
clover, or even from a patch of this plant along the road-
side, since the two kinds of plants require the same bac-
teria. |
The majority of growers in these states prefer not to
sow alfalfa with a nurse crop at all. Instead, they sow
it alone in the late
summer either in land
that has yielded a crop
of small grain or in
land that has borne no
crop but has been kept
idle or summer fallowed.
If stubble ground is
used for alfalfa, it
should be disced and
plowed as soon as the
small grain crop has
been removed. After
this, it should be disced
and harrowed every
few days until later
summer. In this way,
weed and other seeds are induced to germinate and are
subsequently killed; and at the same time moisture from
midsummer showers is stored and conserved.
In late summer, then, the seed is drilled in at the rate
of fifteen or twenty pounds per acre. This should be
done early enough so that the young plants will have
become established before winter. In many sections,
alfalfa is sown in the spring with a nurse crop, just as is
red clover.
Fig. 118. — Putting alfalfa in the mow.
CLOVERS AND OTHER LEGUMES 269
The crop is commonly cultivated at least once each
season, a spring tooth harrow or a disc being used after the
second cutting. In this way, the growth of weeds, in-
cluding blue grass, which is a particular enemy of alfalfa,
may be partly or wholly controlled.
Alfalfa should be cut for hay just after the new shoots
appear at the crowns near the surface of the ground and
before these shoots become so long that their tips will
be clipped off by the mower.
Sweet Clover—There are three classes of sweet clovers ;
viz., the white flowering biennial, the yellow flowering
biennial and the yellow flowering annual. The last one
has little or no value from an agricultural standpoint, while
of the other two, the first is regarded as the superior plant.
Notwithstanding the fact that this plant, which com-
monly grows along roadsides, has long been regarded as
a noxious weed, its value as a feed for live stock is nearly
or quite equal to that of alfalfa when once animals have
become accustomed to it, it is second only to alfalfa in its
ability to restore nitrogen and humus to the soil, and it is
no more difficult to eradicate from a cultivated field than
is red clover.
Since it is a biennial, its cultural methods are similar
to those of red clover except that about twenty pounds
of hulled seed per acre are sown, as sweet clover contains
an unusually high percentage of hard seeds which do not
grow the first year. It will not succeed in an acid soil
nor in one that does not contain the necessary bacteria.
Thus limestone and inoculation are frequently necessary.
Sweet clover differs from other legumes, however, in that
it will thrive in a soil exceedingly low in humus, as in clay
banks and in abandoned fields, provided there is a suffi-
cient supply of lime in the ground. This gives it a value
as a restorer of worn-out soils possessed by no other plant.
270 SOILS AND PLANT LIFE
Owing to the high percentage of hard seeds, a germina-
tion test, such as was made in Exercise 50, should in every
case be made before the seed is either purchased or used.
At least 30 to 40 per cent should prove germinable.
Sweet clover is cut for hay when about twenty to twenty-
four inches in height. If allowed to grow longer, the hay
becomes coarse and woody. In mowing it, a stubble from
four to six inches high is usually left, as otherwise many
young shoots will be cut off and later growth retarded, or
the plants may even be killed outright.
Alsike. — Alsike clover may be used either for pasture
or as a hay crop. It succeeds better than red clover in
poorly drained soils or in those deficient in lime, and for
this reason, it is often grown in fields in which it is known
that red clover can not thrive.
Often-it is mixed with timothy and red clover because
it matures at about the same time, about four or five
pounds of alsike seed per acre being used in addition to
the usual amounts of the other seeds. In this case, it
becomes a sort of substitute for the red clover, that is, in
those spots or places, where the red clover fails, the alsike
usually establishes itself.
White Clover. — The little white clover is the standard
pasture plant among the clovers just as is blue grass
among the grasses.
This clover is not usually seeded, but, like the blue grass,
finds its way into pastures that are suited to it. The seed
will lie in the ground for several years and will germinate
when conditions become right. It may be sown in pasture
mixtures, in which case, from two to five pounds of the seed
per acre may be used.
Japan Clover.— This is an annual clover which is
commonly used in the southern states for pastures
though on fertile soils it sometimes grows to a height of
CLOVERS AND OTHER LEGUMES Peg
twenty-four to thirty inches and may be cut for hay.
Each year a new crop grows from the seed which fell
to the ground from the preceding year’s plants so that
the land may seem to remain in the same crop _per-
manently. -
Japan clover may be mixed with Bermuda grass, making
an excellent pasture, corresponding in a way to the white
clover and blue grass pastures of the North. Its growth
is checked by the heat
of midsummer and it
is killed by the frosts
of winter. It follows
that its chief value
is for spring and fall
pasture.
Cowpeas and Soy
Beans. — These crops
are adapted to the
warmer parts of the
Corn Belt, though soy
beans will succeed
somewhat farther
north than will cow-
peas. Both are grown
quite extensively © in
the South.
They may be sown broadcast in corn at the last cultiva-
tion or drilled between the rows afterwards; or they may
be planted in stubble ground after the small grain is re-
moved. They require a well-prepared seed bed, should be
covered as a rule to a depth of about two inches, and can
not be sown until the soil has become thoroughly warmed
up in the late spring. If sown broadcast, from six to
eight pecks of seed per acre are used; but if they are
Courtesy Iowa State College.
Fig. 119. — Soy beans in field.
22 SOILS AND PLANT LIFE
drilled in, less seed is sufficient. They should not be put
into the ground until danger of frost is past. Inoculation
is often necessary in soils in which these crops have not
previously grown.
Field peas, or Canadian field peas, are grown in the
cooler parts of the Corn Belt and northward, often with
oats as a pasture for hogs or for hay. They are more
hardy with respect to cold than are cowpeas or soy beans.
However, the cultural methods of the three crops are
similar.
The Vetches. —'Two kinds of vetch, the common, and
the hairy, or winter vetch, are rather extensively grown
especially in sandy soils.
They may be sown broadcast in corn or cotton at the
last cultivation. The winter vetch may be planted in.
late summer or early autumn.
Inoculation is usually necessary the first time the crop
is grown. The soil in which garden peas are growing may
be used for this purpose.
Vetch may be used for hay, but it is preéminently a
green manure crop; that is, it is plowed under to add
humus to the soil.
204. Securing the Maximum Benefits from Legumes. —
If the soil is to acquire all the nitrogen which any given
leguminous crop takes from the air, it 1s, of course, necessary
that the latter be plowed under. This, however, is or-
dinarily not done. Rather the hay is fed to animals and
the manure returned to the land. A considerable loss of
nitrogen results from this in most cases; but the profit
derived from the feeding of the hay more than offsets
this.
On the other hand, it is not advisable in any case, if we
consider the effect upon the fertility of the soil, to remove
CLOVERS AND OTHER LEGUMES 273
and sell the hay, retaining only the roots in the land. If
this is done, the store of nitrogen in the soil is not increased
at all as a.rule, while that of other essential elements is
actually diminished.
QUESTIONS
Name six ways in which legumes benefit the farmer.
How do legumes add nitrogen to the soil?
State seven reasons why clovers frequently fail.
How would you test a field for acidity ?
Rank the small grains according to their suitability as
nurse crops for clovers.
6. What is the objection to sowing clover seed broadcast
and harrowing it in?
7. Under what conditions may we attribute clover failures
to drouth or winterkilling ?
8. Name five rules to follow in order to succeed with clovers
and other legumes.
9. How would you correct soil acidity ?
10. How would you inoculate a field for alfalfa ?
11. State in detail how you would make a seed analysis.
12. Why is a germination test particularly necessary before
sowing sweet clover ?
13. Why is sweet clover superior to any other plant for re-
storing wornout soils ?
14. What is the standard pasture plant among the clovers?
15. Why should not the hay from legumes be sold from the
farm?
Site Petre et
CHAPTER XX
THE FIBER CROPS
205. Three Crops yielding Valuable Fibers. — The
plants that yield the supply of material from which
certain kinds of cloth, thread, rope, twine and similar
products are made, are called fiber crops. There are
between thirty and forty plants in the world, which yield
materials of this kind. Only three such crops, however,
are grown extensively in the United States; viz., cotton,
flax and hemp.
In Section 82 we learned that it is a portion of the stem
of the flax and of the hemp which is used in the manu-
facture of linen, rope, and other important products. In
the case of cotton, it is the lint which grows on the seeds
that furnishes the material for cloth, thread and twine.
These vegetable fibers are not only used alone but they
are often mixed with animal fibers, such as wool; or they
are sometimes used as a substitute for the latter. It is
not difficult to distinguish one from the other, however, as
vegetable fibers leave a white ash when burned while animal
fibers leave a dark coal.
206. Valuable Products Other than Fiber. — The value
of these crops lies not alone in the cloth and cordage
material which they yield but also in the rich oils and
protein feeds for animals which come from their seeds.
Cottonseed meal and oil are staple articles of commerce.
Flax seed meal, or linseed meal, as it is usually called, is
extensively used in stock feeding while the oil from the
274
THE FIBER CROPS 275
seed is used in all paints and varnishes of good quality.
Hemp seed oil is used in cooking and in the manufacture
of paints, varnishes and soap.
CorTrron
207. The Importance of Cotton. — Cotton has often
been called the king of crops because it is our leading article
of export. More farm
land in the United
States is planted each
year, however, to corn,
oats or wheat than to
cotton.
The great value of
cotton lies in the fact
that it furnishes the
greater part of the
clothing of the people
of the .éarth. - ‘The
magnitude of the cot-
ton-growing industry
has increased to such
an extent that the
whole economic world
is unsettled when war
or any other disaster interferes with its movement in the
raw or manufactured state to and fro between countries.
Our exports of cotton in a single year ordinarily amount to
more than three hundred million dollars, from which we
may readily see how serious a matter it is to our people
if the ports of the world become closed against it.
Fic. 120. — An opened cotton boll.
208. Where Cotton is grown in the United States. —
The states of South Carolina, Georgia, Alabama, Missis-
276 » SOILS AND PUANT LIFE
sippi, Arkansas, Louisiana and Texas constitute what is
known as the Cotton Belt. There are a number of reasons
why this part of the country has become the leading cotton-
producing section of the world:
(1) The cotton plant thrives best in a climate where the
temperature is uniformly high for four or five months after
the seed is planted, followed by two or three months of
cooler weather. These temperature conditions prevail
in the Cotton Belt. |
(2) The cotton plant thrives on clay and silt loam
soils, which are the predominating types in this region.
(3) The cotton plant makes its best yield when the
rainfall is comparatively heavy and well distributed during
the growing season, followed by rather dry weather during
the picking season. The weather records show that the
Cotton Belt receives its rainfall in about this way.
(4) A cotton crop requires a great deal of hand labor.
Cheap and efficient help can be secured in this region.
(5) Owing to the fact that it is so largely exported,
the crop requires adequate facilities for transportation.
Railroads and steamships quickly move the enormous
number of bales grown in the cotton states from the
various points of shipment.
209. The Cotton Plant. — For those persons who live
where cotton grows, no description of the plant is necessary,
while for others it may be compared with another familiar
plant, a noxious weed, which belongs to the same family.
The Indian mallow, butter print, or velvet leaf, as it is
variously called, belongs to the mallow family, to which
also the cotton belongs.
Both plants have a strong, deep tap root with finer
lateral ones spreading in all directions, often to a distance
of three or four feet from the main root. Both have
THE FIBER CROPS pA
‘ stout, erect stems from one to five feet tall with wide,
spreading branches, the longest ones being nearest the
ground and the shortest ones at the top. The flowers of
both are regular, with five petals which are creamy white
or yellow in color. The butter print flower remains open
but a short time while
the flowers of many
varieties of cotton
open in the early
morning, showing a
creamy yellow color,
turn pink or red dur-
ing the day and at
nightfall close never
to open again. The
pistil of the flower of
either butter print or
cotton develops into a
boll. When ripe,
these bolls open, ex-
posing dark-colored
seeds. Those of the Fic. 121. — Cotton seeds with lint.
butter print show a
trace of lint when examined under the hand lens, while
the lint on the cotton seed is pearly white and from one-
half to two and one half inches long.
210. Growing the Cotton Crop. — Rotation. — The
chief criticism offered to the methods practiced by cotton
growers is that they raise this crop in the same fields too
many years in succession, selling the fiber and seed and
returning nothing to the land.
The yield of the crop is in proportion to the fertility of
the soil. To maintain this fertility, a rotation of at least
CV bean a SOILS AND PLANT LIFE
two or three years is essential, as, for example, cotton
followed by crimson clover the first year; corn, the second
year; and wheat followed by cowpeas the third year.
Itis unnecessary that the field occasionally “lay out,” that
is, be left idle to grow up to weeds for two or three years.
A rotation, moreover, tends to hold in check that
dreaded enemy of the cotton grower, the boll weevil.
Fertilizers. — There is probably no general crop grown
in this country upon which commercial fertilizers are so
extensively and profitably used as upon cotton. The
Georgia Station has found after fourteen years of experi-
mental work that upland, worn soils should receive nitro-
gen, phosphorus and potassium in the ratio of three, ten
and three.
On many of the prairie soils containing plenty of lime,
the use of commercial fertilizers is not profitable, while
even on soils where their use now brings returns, a careful
rotation will greatly lessen the need of them.
Seed Bed and Seeding. — Land which is to be planted
to cotton should not be left bare during the winter. Crim-
son clover, bur clover or winter vetch, sown in the fall and
plowed under not later than February first, will make a
loose, fertile seed bed.
If a fertilizer is to be used, it is often placed in a furrow,
opened by a lister, or ‘‘ middle buster,” as it is called.
The soil is then thrown back over the fertilizer with a small
plow; and the seed is planted over it with a slight furrow
left between the rows.
Another method used is to open the furrows with a
lister, or middle buster, from three to four feet apart, and
to plant the seed on the ridges with a single row planter,
adding fertilizer with the seed as desired.
The practice has been to plant from one to three bushels
of seed per acre, which means from 100,000 to 600,000
THE FIBER CROPS 279
i Ad vo eates | Ie
Copyright by Underwood & Underwood.
Fic. 122. — Negroes picking cotton.
280 SOILS AND PLANT LIFE
seeds. When the plants have pushed their way up out
of the ground, most of them are cut out, leaving those
not destroyed about eighteen inches apart in the row.
It is an excellent practice to use only large, plump seeds,
planting fewer of them per acre and applying cottonseed
meal as a fertilizer for the growing crop.
Cultivation. — A sweep cultivator which stirs the ground*
two or three inches deep is commonly used. It leaves a
loose mulch on top, conserves the moisture, helps to make
plant food available, destroys weeds and brings about
that continuous, rapid growth so essential to a satisfactory
yield of cotton.
211. Harvesting the Crop. — One of the characteristic
scenes of the South is that of cotton picking. No machine
has ever been invented to gather cotton satisfactorily,
for the bolls ripen successively, which means that the
field must be gone over several times.
Picking usually begins in late August and continues
until the first of November. Fitted over the shoulders
of the pickers and trailing out to a distance of perhaps
ten or twelve feet behind them, are the picking sacks,
in which the seed cotton is placed. From these sacks it
is transferred to deep-boxed wagons and hauled to the gin.
212. Ginning the Cotton.— From the wagons the
cotton is unloaded or drawn by suction into the hoppers
where revolving saws remove the lint from the seed.
The lint is removed from the saws by revolving cylinders
and drawn by suction into a condenser, from which it
passes on to the press. The fiber comes out from these
power or screw presses in bales of five hundred pounds.
As the seeds are separated from the fiber by the saws,
they drop through “openings and those which are not
THE FIBER CROPS 281
saved for planting are reginned to remove the clinging
lint. Their hulls are then removed and the embryos, or
‘““meats,’’ of the seeds cooked for about fifteen minutes
to drive off the water and melt the oil. Pressure is then
applied to extract the oil, which goes to the refinery.
Copyright by Underwood & Underwood.
Fic. 123. — Bales of cotton ready for shipment.
The remainder is dried, cooked once more and ground
into cottonseed meal.
213. Proportion and Value of Seed and Lint. — It takes
about fifteen hundred pounds of cotton as it comes from
the field to make a five-hundred-pound bale.
282 SOILS AND PLANT LIFE
The value of the lint lies in its cheapness, flexibility,
uniformity and wearing qualities. It is spun and woven
with ease into nearly all kinds of fabrics.
The hulls of the seeds are used for fuel, as a fertilizer,
as a feed for cattle, and for paper stock, while the oil is
used in the manufacture of oleomargarine, as a substitute
for olive oil, in lard compounds and for other culinary
purposes. The cake left after the oil is extracted, or
the meal made from it, is used as a feed for stock and
as a fertilizer.
RiAax
214. How and where Flax is grown. — The production.
of flax has moved westward and northward as the newer
parts of the Mississippi
Valley have been set-
tled. The pioneers
have broken up the
prairie sod, and while
they were waiting for
it to decay sufficiently
for wheat to grow, they
have raised a crop of
flax. This new land
has hitherto been
abundant enough to
supply the amount of
flax required in this
country.
Flax thrives and is
raised principally in
northern Europe,
where a cool, moist
atmosphere exists. This explains in part why the states
of Minnesota, North Dakota and South Dakota produce
the greater part of the crop raised in this country.
Fic. 124, — Flax plant and fiber.
THE FIBER CROPS 283
Flax seed is sown in the spring, the average depth at
which it is planted being about one inch. Like wheat,
the crop requires no cultivation after being sown. If
seed is desired, the stand should be somewhat thin in
order that the plants may branch well. On the other
hand, if fiber is wanted, the seed is sown thickly to
make the plants grow tall and straight. When sown
for seed, from one to three pecks per acre are used
while nearly four times this amount of seed is sown
for a fiber crop.
Flax is cut with an ordinary self-binder, and is considered
one of the most pleasant crops to handle. It has long
been regarded as one of the most exhaustive crops
grown on any soil. A disease, known as flax wilt, develops
when the crop is raised a second or third year in succession
in the same field; and many growers believe that it is
this disease, rather than the gross feeding habit of the
plant, that has given it so bad a reputation.
215. Methods of Handling and Value of the Fiber and °
Seed. — After the crop has been cut with the binder, or
pulled by hand as is sometimes done, it is placed in shocks
and allowed to stand for two or three weeks. If the fiber
is desired, the seed is then removed by passing the heads
between rapidly revolving cylinders or rollers, which
crush the seed pods. The straw is bound into bundles,
and later, usually in October or November, it is spread
out on the ground to “ ret,” or rot. During this process
the portions of the stems, other than the bast (Section 82),
decay, or become sufficiently softened to permit an easy
separation of the parts. The long, straight fibers, from
one to three feet in length, are called long lint while the
short and tangled ones are called tow. From the former,
fine laces, linens, dress goods and thread are made, while
284 SOILS AND PLANT LIFE
bagging, upholstering material and twine are made from
the tow.
Flax fiber has been called ‘‘ the fiber of luxury,” while
cotton has been called “‘ the fiber of the masses.”’
If the crop is not raised for the fiber, but only for the
seed, it is threshed with an ordinary threshing machine.
The seed secured is eventually crushed, after which it is
heated to about 165 degrees Fahrenheit, placed between
layers of coarse cloth and the oil extracted by pressure.
The solidified mass remaining is known as oil cake. This
cake may be ground, in which case it is called ‘ old pro-
cess linseed meal.” If the oil is extracted, not by pressure
but by the use of petroleum naphtha, the remaining meal
is known as ‘‘ new process linseed meal.’’
Oil cake and linseed meal are among the most valuable
protein feeds for live stock known. Linseed oil is used in
making paints and varnishes, printing ink, linoleum, soap
and artificial India rubber.
HEMP
This plant is a coarse annual, growing from eight to
twelve feet tall and yielding a rather coarse fiber which
is used in making cordage and warp for carpets. The
crop demands a somewhat warmer climate than does
flax and in this country is raised principally in the blue
grass regions of Kentucky and Tennessee. The crop does
not exhaust the soil so quickly as flax; and if the waste is
returned to the field, it may be grown several years in
succession on the same land.
The hemp crop is cut with a heavy mower or with a self-
rake reaper, or it may be cut by hand.
The fallen plants are allowed to lie on the ground until
the dews and rains have “ retted,’’ or rotted, the stems.
-
THE FIBER CROPS 285
Then it is stacked and later the fiber is separated by
machinery. The seed is not so eagerly sought by paint
manufacturers as is that of flax, although considerable
Fic. 125. — A Kentucky hemp field.
use is made of it as an ingredient of oil colors and var-
nishes. |
QUESTIONS
1. Name the three principal fiber crops of America and tell
where each is grown.
2. What two portions, or parts, of these fiber plants are
used and why is each valuable?
3. Name five reasons why the southern part of the United
States is adapted to the culture of cotton.
4. Give a good crop rotation for a cotton plantation and
tell why such a rotation is important.
5. State briefly how to prepare and plant a field of cotton.
6. Tell briefly how cotton is picked and how the seed is
separated from the lint.
286 SOILS AND PLANT LIFE
7. Why is cotton lint, or fiber, so extensively used by the
‘*masses’”’ ?
8. In what kind of soil is flax usually grown?
9. What is the principal use of flax seed, and for what is the
fiber used ?
10. Describe the hemp plant and tell how it is harvested and
for what the fiber is chiefly used.
A
CHAPTER XXI
FRUIT GROWING
216. Horticulture and Agriculture. — In ancient times,
the people lived together within walled cities for protection
and cultivated ‘‘ intensively ”’ the small plots of land within
the inclosures. The larger fields were outside and could
not be so carefully attended as those within.
The Latin word hortus means a garden, or inclosure ;
ager, afield; and cultura, cultivation or culture. Thus the
word horticulture has come down to us meaning the care,
or culture, of those crops which were grown within the
walled cities; viz., fruits, vegetables and flowers, while
agriculture signifies the cultivation of grain crops, grasses
and other crops grown in the large fields outside.
The older a country becomes and the denser its popula-
tion, the fewer are the field crops grown, while fruit and
vegetable crops tend to increase.
217. Where our Fruits originated.—-If we were to
travel from New York to Seattle, passing through Chicago,
Omaha, Denver and Salt Lake City on our way, we should
find apple crchards, large or small, in most places along
our route where the land is capable of cultivation. Then
if we were to journey down the Pacific coast, we should
find prune, peach, orange and lemon orchards and the
vineyards which yield our supply of raisins, as well as large
red or white solid-fleshed grapes. In the southern part
of California and in Arizona, the date flourishes; and in
287
288 SOILS AND PLANT LIFE
this same district and extending eastward into Texas, we
should find the fig. In the Cotton Belt and extending
slightly north of it, large orchards of peaches grow,
and in Florida, the orange, lemon and grapefruit grow
in abundance.
Did all these fruits originate on this continent? Not
one. All of them came to us from Europe or Asia, having
been introduced into this country by the white man. These
fruits have, however, been improved and selected according
to adaptation to different soils and climates of the United
States. Moreover, the native fruits of other kinds which
the first settlers found growing here have been improved.
From the wild cranberries, plums, raspberries and grapes,
have come thousands of superior varieties worthy of a
name and of a place in our gardens and orchards.
Not many of those varieties of apples, oranges, peaches
or other fruits which were originally introduced from
foreign lands are now to be found growing in American
orchards. They have been replaced by better varieties,
the offspring of these foreign parents.
It is an interesting fact that almost none of these
superior varieties have come from known parents. A
seed may be dropped on the roadside by a bird or a
thoughtless passer-by; a tree springs up, and by one
chance in a thousand perhaps, or even less, its fruit proves
to be better than any other similar fruit growing in that
locality. Buds or twigs are taken from it and united with
other plants of the same species, the variety is given a
name, and it thus becomes introduced into cultivation.
218. Developing the Young Tree. — After the budding
or grafting has been done as explained in Section 104,
the young tree is trained in the nursery for one or more
years. It is then taken up with as many roots as can be
FRUIT GROWING 289
conveniently secured, packed in moist moss and straw
and shipped to the person who wishes to plant it.
219. The Location of the Orchard. — The location of a
young orchard should not be chosen hastily or without
careful consideration. In the selection of an orchard
site, these factors should be kept in mind:
(1) Convenience to the home and to a desirable market
if fruit is to be raised to sell.
(2) Sow. — Each fruit has a particular type of soil upon
which it succeeds best. This can usually be determined
by studying different orchards in your own locality.
(3) Water Drainage. — There is an old saying that
fruit trees do not like wet, feet. The gravity water
(Section 12) in any orchard site must be removed by
drainage before the plants will thrive.
(4) Air Drainage. — It must be remembered that air
drains like water. The cold air is the heavier and settles
into the ‘ pockets,’’ or low places; and if trees or vines
are planted there, they are very liable to be injured by
the frost.
220. The Distances between the Trees.—TIf the
location and soil preparation are satisfactory, we must
next determine the distances at which the various plants
make their best growth.
‘The following table of distances between the plants is
recommended, though it may be varied slightly on
different soils and with different varieties.
PUDICS? i. wa te a ee Oech ach WAY
Beate ee Pye eres a teal) to 25 feet each way
Peaches and nectarines . . . . 20 feet each way
ROS, tay hy ae ee aan OOtoet cach way
MPTICOUS) 63/92 se he eat A. e200 feet: each way.
U
290 SOILS AND PLANT LIFE
Cherries. ..s.2 Show ect oe a ZO teetesch way
Cherries (sweet) . . . . . . . 980 feet each way
IGS ha VS ya ee . . 20 to 25 feet each way
Oranges and lemons... . . 25 to 30 feet each way
Grapes: nage foe at SO OS ee borer anne
Currants.) 2.020 0s ae Poe x Oofeet. 1020 arene
Blackberries.22 2.0.7) 2 re oe. See A Heeb Ge tees
Raspberries.) so. ancy un oh DR PS KO feet 080 ae ee ere
Strawberries: ech ey, Bhd a A SC 8 Feet, GO eee
221. Cutting back and Planting the Young Trees or
Vines. — Suppose that the trees or vines have been re-
Fic. 126. — Trees cut back for planting.
ceived from the nursery. They must be protected from
the sun and wind until they are planted; and moreover,
only as many should be taken to the orchard at a time as
can be protected while the work is going on.
It is impossible to remove a tree from the nursery row
or from the ground elsewhere without cutting away a part
of the roots. The top must be cut back then, to offset this
loss of roots. It may be given almost as a fixed rule that
young trees should be cut back at least one half of the last
season’s growth and vines and shrubs should be cut back
FRUIT GROWING 291
to the ground, leaving only two or three buds on the short
stems.
A tree should be planted slightly deeper than it was in
the nursery row, the roots well spread out, and the soil
packed firmly about them.
222. Cultivation of the Young Plants. — We are al-
ready familiar with the reasons for tilling the soil, but we
cannot apply these principles in fruit growing without
knowledge of the needs of the roots of our trees and vines.
The root systems of fruit-bearing plants have been thor-
oughly studied; and, as will be seen, the cultivation
of each one must be governed largely by the character of
the underground part of the plant.
(1) The Strawberry. — This plant has a shallow root
system which does not extend far beyond the area covered
by the leaves. Strawberries must receive frequent and
shallow cultivation or be mulched with straw between
the rows to produce the best fruit.
(2) The Raspberry. — This plant, too, has a shallow
root system and can not endure deep cultivation as the
heavy main roots will be torn out or cut off. Moisture
should be retained with a dust or straw mulch.
(3) The Grape. — The grape has a deep root system and
should therefore receive thorough cultivation, while the
plant itself delights in a deep, porous, even gravelly soil
where its feeding roots may range deep and wide.
(4) The Tree Fruits. — Most tree fruits, as the apple,
pear and cherry, have deep feeding roots; and in those
soils in which the roots are able to. penetrate deep and
wide, cultivation is used principally to put the soil in a
condition to receive and hold moisture. In fact, as the
trees become older, the orchard may be planted to some
annual or biennial clover. Grasses, however, which are
292 SOILS AND PLANT LIFE
likely to rob the trees of their moisture, and those which
allow the water to run off instead of soaking into the
ground, should not be allowed to take possession of the
soil.
223. The Training of the Young Plants. — The training
of the young plants must begin the same season they are
set out, as usually the first few seasons determine the
form of the tree or vine. Three facts should be kept in
mind in pruning, or training any young trees, limbs or
vines :
(1) Each plant should be so placed and trained that all
its leaves may receive plenty of sunlight in order that they
may manufacture an abundance of food for the plant.
(2) Except in a very few localities in the United States,
the main limbs of a tree should be quite close to the ground.
A low-headed, vase-formed tree is less liable to injury
from wind and sun, the branches receive plenty of light,
and the fruit is much easier to gather.
(3) Heavy pruning, one year in many, upsets the habits
of the plant and results in too much wood growth. On
the other hand, those pruned lightly each year maintain
a normal, healthy growth.
224. When and how Fruit Buds form.— When by
proper cultivation and pruning we have developed a
tree or vine of the type which we desire, we must turn our
attention to making it bear fruit.
Fruit develops from blossoms. Blossoms develop from
blossom buds, or fruit buds, as they are called. And these
blossom buds develop from slight enlargements, or pro-
tuberances, within the protecting leaf buds.
If we were to take two or three eggs each day from an
incubator, break them open and examine them, we could
FRUIT GROWING 293
trace the development of a chick until it is fully formed.
Similarly, by cutting open buds every week from the first
of July until the first of the following April, and examining
them under a powerful microscope, we can trace the de-
velopment of a blossom.
At some time about the middle of the growing season, —
often as early as July first with apples, plums, peaches and
cherries in the central parts of the United States — a
sight protuberance may be found within the protecting
scales at the base of a leaf bud. It is the beginning of a
fruit bud; and as the season advances, the parts of the
flower are slowly formed within the bud, — first, the sepals,
next, the petals, then the stamens and lastly the pistil.
When the warm days of spring come on, the protecting
scales open and the full flower expands.
225. Conditions which favor the Formation of Fruit
Buds. — While it is not possible for a fruit grower to
control all the conditions which surround his plants, it is
surprising how many things he can do that favor the for-
mation of fruit buds; and we must remember that an
abundance of fruit buds usually means a crop of fruit the
following year.
Two principles must be kept in mind; and with these to
guide him, the fruit grower is able to control in a measure
the yield of fruit from his orchard from year to year :
(1) Fruit buds form when the plants are in a healthy
condition and full of reserve food. (Section 70.)
(2) Fruit buds form when there is a check in the growth
of the plants.
We can readily see how a grower may keep his plants
in healthy condition and full of reserve food by cultiva-
tion, by pruning, and by the addition of organic matter
to the soil if need be; and how he may favor their
294 SOILS AND PLANT LIFE
growth by protecting them against disease (Section 99)
and insects.
But how is he to check their growth?
The fruit grower in the irrigated country will tell you
that it can be done by withholding nearly all water from
the trees during the latter part of the growing season.
The man who cultivates his orchard will tell you that
you can check the growth by stopping the cultivation early
in July and sowing oats, rape, buckwheat, vetch or some
other crop which will take the moisture and plant food
from the soil.
The man who once had a very healthy orchard in the
central part of the United States, but all growing perhaps
to heavy wood and bearing no fruit, will tell you that he
pruned his trees in June and that the next year he had a
full crop.
Your grandfather would probably have told you to
drive into the body of the tree rusty nails or small bolts.
The man who prunes and cultivates, who checks his
irrigation stream, or who sows a crop in his orchard at
midsummer is thinking about securing a crop of fruit, and
at the same time about keeping his trees in healthy con-
dition. Grandfather’s method produced fruit, but in
many cases it shortened the life of the tree. A tree that
is injured by rabbits or mice, by storms or by careless
treatment is very likely to bear fruit the next year, — and
the next year it is apt to die.
By careful soil management, by proper pruning, by
intelligent irrigation, by timely spraying, and by thinning
the fruit, we can aid the fruit buds to form and at the same
time maintain healthy, long-lived trees.
226. Age of Wood upon which Fruit Buds appear. —
One of the most interesting ways to fix in mind the dif-
FRUIT GROWING 295
ference between a leaf bud and a fruit bud is to examine
them at any time in the winter. You will find then:
(1) That the fruit buds of the cherry and plum are in
Fic. 127. — A Fig. 128.— An Fic. 129. —A
cherry twig as it apple twig in win- peach twig as it
looks in winter. ter. looks in winter.
clusters on short spurs while the leaf buds lie close
against the twig.
(2) That the fruit buds of the apple are likewise borne
on spurs, but that there is usually only one on each spur
while the leaf buds lie against the twig.
296 SOILS AND PLANT LIFE
(3) That the buds of the peach are in clusters of three,
not on spurs, but lying close against the twig, the middle
one of each cluster being a leaf bud while the other two
are fruit buds.
By studying Figures 127-129, or better still the twigs
themselves, you will see that not all varieties of fruit buds
are borne on wood of the same age. There is always
a set of rough rings, or wrinkles, separating each year’s ©
erowth on a twig from that of the year before; and by
beginning at the tip and counting the sections, or divisions,
between these rings, you can easily determine the age of
any portion of the twig or branch.
EXERCISE 51
Object. — To learn the form and position of fruit buds
and the age of the wood upon which they appear.
Procedure. — Secure a branch or twig three feet or more
in length of a cherry, peach, plum, apple, or other fruit tree,
and lay it on the desk or table before you.
Examine it carefully for the rough rings, which separate
the wood of different years’ growth. Then point out the
fruit buds and note that they are usually plumper, as
well as grayer or darker in color than the leaf buds, while
the leaf buds, which lie along the twig, are usually rather
pointed in comparison with the fruit buds.
Conclusion. — Describe carefully in your notebook the
color, form and position of both the fruit buds and the leaf
buds, and state the age of the wood upon which the fruit
buds appear.
Make a drawing of the twig to show this.
Put your twig in a vase or glass of water so that the buds
may open.
The fruit of the grape is borne on wood, or canes, of the
same season’s growth as the fruit itself, — not on the wood
FRUIT GROWING 297
of the year before, or the second, third, or fourth year
before as is the case with most of the tree fruits. Re-
member to examine your grape vines next year to see that
this is true.
We readily see then how closely the questions of fruit
buds and pruning are related.
The clusters of fruit that you will pick from your grape
vines next fall will be borne only on the young, new wood
formed during the spring and summer; and because of
this fact, the old wood should have been pruned away
last fall, save only a very few canes from which the new
ones might grow. This would cause the plant to devote
its entire strength and vigor to the development of the
new fruit-bearing wood as well as to that of the fruit
itself.
The fruit of the blackberry and raspberry, like that of
the grape, is borne only on the new twigs, or wood, of the
same season’s growth as the berries themselves; and these
new twigs branch only from those canes which have grown
up from the ground the year before. This means that the
twigs from which you will gather berries next summer will
be found branching out from canes that came up from the
ground last summer, — and these twigs will not begin to
grow until spring has come. Therefore you should have
cut away all old wood that had borne fruit as soon as the
crop was gathered last summer so that the new canes could
have possession of the ground.
Peaches are always borne on twigs of the previous season’s
growth. It follows that pruning should have been done
last summer to induce the growth of new twigs from which
the next season’s crop must come. |
Plums and cherries usually, but not always, are borne
on wood that is two years old, and fortunately these trees
get along well with very little pruning:
298 SOILS AND PLANT LIFE
Apples are usually borne on wood older than two years,
and frequent use of the pruning saw and knife must be
made to induce the fruit spurs on these trees to develop
where we want them.
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A peach twig ' Fie. 131.— A cherry Fic. 132. — An apple twig
as it looks in twig as it looks in as it looks in spring.
spring. spring.
227. The Reasons for Pruning. — We have studied
about pruning in connection with the training of the
FRUIT GROWING 299
young trees or vines and also as a means of inducing the
formation of fruit buds. Let us bring together the reasons
for this important operation. They are:
(1) To regulate the size and shape of the tree or vine.
(2) To remove unnecessary and rubbing twigs or small
limbs which prevent the sunlight from reaching the fruit-
bearing wood in the inner parts of the tree top.
(3) To remove any dead or diseased portions of the
plant. Many of the diseases of both the limbs and the
fruit may be controlled by cutting out and burning the
limbs as soon as the blights or cankers appear.
(4) To increase the vigor and health, and thereby the
wood growth of the tree or vine. Plants which have a feeble
root system are greatly benefited by pruning, while the
rate of growth of healthy trees is increased in the same way
if the work is done in the dormant season.
(5) To increase fruitfulness. As has been shown, check-
ing the growth of trees and vines tends to stimulate the
formation of fruit buds. Pruning in the early summer,
unlike that done in the winter, checks the growth of wood
and favors that of fruit buds.
Fia. 133. — Grape vine pruned to a double T.
228. Methods of Pruning. — With the reasons for
pruning clearly in mind, we are ready to take up the
methods of performing this important work. These will
300 | SOILS AND PLANT LIFE
vary somewhat with the age, variety and vigor of the plant,
and with the locality in which it is grown.
The Grape. — Many methods are used in pruning the
grape vine, but only one will be given here:
Fic. 134. — Peach trees headed back.
The young vine is trained up a two-wire trellis and there
encouraged to form a letter T with a second letter T 1m-
mediately above it. The erect stems of the two letters,
then, are of wood, usually as old as the vine itself, while
the spreading ‘‘ arms ”’ are of wood of the previous season’s
FRUIT GROWING 301
growth. From the buds, which may be readily found on
these arms, are to come the branches that will bear the
fruit.
The grape should be pruned in the late winter, when
all the wood should be cut away save the old stems
and four new branches, less than one year old, which
will form the arms of
the two T’s.
Raspberries and
Blackberries. — Soon
after these berries
have been picked, the
canes which bore them
die, and beside them,
growing up from the
same root, are found
new canes.
The old canes should
be removed as soon as
the fruit has been
gathered,. and early
the following spring
the new canes should
have their very tips
pruned off as this
favors the development of the lateral twigs, or branches,
which are to bear the fruit.
Cherries and Plums. — Cherry and plum trees need little
pruning, save to remove the dead, diseased or broken
limbs, or those which densely shade the inner parts of the
tree top.
Peaches. — Peach trees tend to grow tall. Their buds
are sometimes killed in the winter by the severe cold.
We can tell when this has happened by cutting through the
Courtesy Iowa State College.
Fic. 135. — Apple tree before pruning.
Oe SOILS AND PLANT LIFE
buds in the late winter with a sharp knife. If the middles
are black instead of a healthy green, we need expect no
peaches. This, then, will be the year to “ head in” our
peach trees; that is, the main branches are cut back a
part of their length. New twigs will grow vigorously
from them to form buds for the next season’s crop.
Apples. — The best
form of an apple tree
is one which has a
low, vase-shaped, open
head, or top. In de-
veloping a young tree,
it is not difficult to
produce this vase-like
form. Two branches
will be found growing
from the same limb,
one tending to grow
upright and the other
to spread. The up-
right one should be re-
moved, and thus the
spreading vaselike
forms will be de-
veloped.
Even after the tree has reached its full size, the
pruning must be continued in about the manner ex-
plained below :
First. — Remove all water sprouts, — those long, slen-
der, switchlike branches, which bear no fruit. If, how-
ever, a part of the tree top is found vacant, one or more of
these water sprouts should be encouraged to grow in that
direction. By cutting them back later, we can induce
them to bear fruit.
Courtesy Iowa Slate College.
Fig. 136. — Apple tree after pruning.
FRUIT GROWING 303
Second. — Remove all dead limbs, all limbs which rub
or injure others, and those which make the inner parts of
the tree dark and damp.
In pruning apple trees, it is better to begin at the top of
the tree and work downward, opening the outer branches
so as to let the sunlight in and give the tree the desirable
vase-like form, than to begin at the bottom and simply
remove some of the large limbs.
Strawberries. — We do not ordinarily regard pruning
as necessary or desirable for strawberries; yet there
are few plants which
really need it more,
at least while they
are very young.
When a strawberry
plant is set out in the
spring, all its vigor
and strength should
go to the develop-
ment of a strong root
system. The runners
which it sends out
and the blossoms which it puts forth should be cut
away.
About the middle of the growing season, however, the
runners may be distributed along the row as they appear
and allowed to take root. After this, the space between
the rows should be kept cultivated or mulched, and the
runners should be kept out of them.
If after two or three years the rows become matted,
the runners may be allowed to take possession of the
space between them, and the old rows may be plowed or
hoed out. In this way, we can virtually secure a new bed
with little effort.
Fig. 137. — Strawberries.
304 SOILS AND PLANT LIFE
229. Precautions to be taken in Pruning. — Care must
be exercised not to remove the fruit spurs, which we should
be able by this time to recognize, nor to remove so much
wood in a single season that the roots and top of the tree
will be thrown out of ‘‘ balance.”’
We should bear-in mind that pruning for vigor; 7.e.,
for wood growth, is
usually done while the
plants are dormant, —
usually in the late win-
ter; but pruning as a
means of checking the
growth of the tree is
done during the grow-
ing season. Pruning
for wood growth is usu-
ally a severer opera-
tion than that which
is intended to check
the growth and induce
the formation of fruit
buds. Indeed, the
latter may consist
only of pinching the
ae terminal buds from
Courtesy Iowa a College. the branches. This
Fig. 138. — Improper pruning. summer pruning of
trees and vines must
be done with caution, for a plant which is already
somewhat weakened may be injured by pruning at this
time. The most important end to be gained in pruning
is the filling of the tree with reserve food, and this is ac-
complished by pruning for wood growth.
In pruning off either large limbs or small ones, the cuts
FRUIT GROWING Bh Reis
should be made close to the limbs or trunks which support
them, for a long stub like those shown in Figure 138
eventually decays, leaving a hole in the tree into which
enter in regular order first moisture, then spores of decay,
and finally the decayed wood itself, which may extend
far into the trunk or limb. On the other hand, acut made
close to the tree heals over in a very few years. As a meas-
ure of safety, however, the stubs of large limbs, even
when cut off close to the tree, should be painted with
white lead and unboiled linseed oil to exclude the mois-
ture and spores of decay which might otherwise enter.
230. Protecting Fruit-Bearing Plants from their Ene-
mies. —
Mice and Rabbits. — During the winter months, dam-
age is often done, particularly to young trees, by mice
and rabbits. They gnaw away the bark and cambium
layer from about the trunk, thus stopping the downward
current of food and causing the roots to starve, as explained
in Section 79.
If the trees, bushes or vines are covered with lime-sul-
fur spray mixture, which may be purchased at any drug
store, the mice and rabbits will be repelled. It may be
necessary to paint the solution on the trunks of the trees
with a brush, especially if the rabbits are. numerous and
the ground covered with snow so that they have trouble
in finding other food.
Frost. — The first way — and a very important one —
of securing protection against frost is to choose a proper
location for the orchard. A body of water, a belt of timber,
a windbreak, and always good air drainage will help in pre-
venting injury by frost. However, in even the best of
locations, frosts will sometimes occur.
Low growing plants like the strawberry may some-
times be covered with straw or hay.
x
306 SOILS AND PLANT LIFE
A blanket of smoke from burning litter will prevent
the escape of heat from the soil and in this way will often
prevent frost. Among the interesting sights to be seen
at times in some commercial orchards are the long lines of
pots of burning oil or coal, which make a dense smoke and
: Courtesy Iowa State College.
Fic. 139. — Keeping Jack Frost away.,
at the same time generate heat enough to keep the tem-
perature of the orchard above the danger point.
Sunscald. — Undue exposure of the trunks of young
trees to heat and cold may destroy. a part of the bark,
producing what is known as sunscald. Binding a layer
of cornstalks, wood veneer or burlap about the trunks
will protect them in the winter and early spring. These
FRUIT GROWING 307
should, however, be removed during the growing season.
As the tree becomes older, the low, vase-shaped top will
protect the trunk.
Insects. — Injurious insects are divided into two classes ;
viz., those that chew, or eat the tissues of the plant, and
those that suck the juices from it.
In the first class, we find such insects as the apple worm,
or codling moth, the canker worm, the strawberry leaf
eater and the po-
tato bug. These
insects devour the
leaves or fruit,
leaving nothing
but the mere skele-
ton of the leaf or
perhaps a fruit
filled with long
tunnels to show
where they have
eaten their way
through.
Inasmuch as
these insects de-
vour the parts of
the plant, they may be destroyed by applying a mist, or
spray, containing some deadly poison, such as Paris green or
lead arsenate. The latter is usually the more satisfactory
because it stays on the leaves better and never burns them
as the Paris green sometimes does. If two pounds of lead
arsenate are dissolved in fifty gallons of water, the solution
will destroy almost any chewing insects. It is used as a
spray as they appear.
In combating strawberry worms or cabbage worms, it
is often unsafe to use either of the poisons named above.
Fig. 140. — Codling moth and its work.
308 SOILS AND PLANT LIFE
In these cases, hellebore or pyrethrum (insect powder),
may be substituted.
Those insects which suck, as the plant lice, or aphids,
and the melon bugs, push their ‘‘ beaks ’”’ down into the
tissue of the leaf or fruit and take out the juices, destroying
the plant or a part of it in this way. No poison, applied
to the surface of the leaf, will affect them. A spray of
Courtesy Iowa State College.
Fia. 141. — Spraying an orchard.
tobacco decoction, lime-sulfur, or kerosene and _ soap,
applied to the plants, comes in contact with the bodies
of the insects and destroys them. The tobacco decoction,
which is called nicotine sulfate, or Black Leaf 40, and the
lime-sulfur preparation may be purchased at most drug
stores. Directions for dilution and application accompany
the mixtures. The kerosene and soap mixture, called
kerosene emulsion, is made as follows:
FRUIT GROWING 309
Dissolve a half pound of laundry soap in one gallon
of boiling rain water. Remove from the fire and add
two gallons of kerosene. Churn, or mix violently, until
you have a light, creamy mixture. Dilute this mixture
with from twenty to twenty-five times as much water for
plants in full leaf.
Fungous Diseases. — We have already studied at some
length in Section 98 how the spores of disease are spread
and how they may be controlled. With nearly all fruits,
it is best to apply a spray of Bordeaux mixture or lime-
sulfur just before the leaves expand. Another applica-
tion, with lead arsenate added, should be made just after
the petals have fallen from the blossoms. One or more
applications of this spray may be necessary during the
_ growing season if insects or diseases are feared.
One ought not to try to remember all of the sprays and
when to apply them, but to keep in the bookcase instead,
one of the government or state bulletins, which gives the
whole spraying schedule. These bulletins can be had for
the asking.
931. Gathering and Storing the Fruit. — Now that we
have assisted in the formation of fruit buds, have kept
away the rabbits and mice during the winter, have pro-
tected the developing blossoms and fruit from the danger
of spring frosts, and have brought them unharmed past
the strongholds of their enemies, insects and diseases, we
have a right to expect as our reward luscious, mellow, fra-
grant fruit; and whether we expect to eat it soon after
gathering, or to store it away to eat in the long winter
evenings as we are gathered about the fire, we must
exercise care in harvesting it.
Three rules, which need no explanation, should be ob-
served at picking time:
310 SOILS AND PLANT LIFE
(1) Pick in the cool of the morning.
(2) Handle the fruit as few times as possible.
(3) Avoid bruising it as much as possible.
Fic. 142. — Boxes of apples.
Fruits which are to be stored away, such as apples and
pears, should be picked while they are firm, wrapped in
papers, and packed away in boxes in a cool cellar where the
dry, hot air from a furnace room can not reach them.
QUESTIONS
1. What is meant by the term horticulture.
2. Name three important fruits which originated in America
and three which originated in foreign countries.
3. Name four points to be considered in locating an orchard.
4. Why do we cut back young trees and vines at the time of
transplanting ?
5. Under what two conditions do fruit buds form ?
6. Upon wood of what age is the fruit of the grape, the peach
and the apple borne ?
7. Give five reasons for pruning.
8. Name three rules to follow in picking fruit.
9. Name two classes of insects, telling means of control.
CHAPTER XXII
VEGETABLE GROWING
Tuoss plants, known as vegetables, which are grown for
their roots, stems, leaves, or fruits, may be roughly divided
into cool season crops and warm season crops. There are
some plants, which must be started in the cool season, but
which continue to grow throughout the summer. Plants
of this kind will be considered here among the cool season
crops.
232. Cool Season Crops. — Almost all of the vegetables
which are grown for their roots, stems or leaves, fall into this
class.
The seed of those which are grown for their roots, such
as the radish, carrot, parsnip and beet, will germinate
while the soil is yet quite cool and make their best growth
before the heat of summer comes on. In order to succeed
well, all of the root crops require a deep, rich, loose, mellow,
cool soil, plenty of surface cultivation and enough moisture
and cool weather to keep them growing rapidly.
The potato, which may also be regarded as a root crop,
though the tuber is really an underground stem, likewise
delights in a cool climate and a rich, deep, cool soil, which
contains enough humus to give it a large moisture-holding
capacity.
Onions, together with a number of less common vege-
tables, such as the shallot, leek, garlic and chive, are known
as bulb crops, for they all grow from, and produce a bud
in the middle of a cluster of, shortened, thickened leaves,
311
34 (Y SOILS AND PLANT LIFE
known as a bulb. These plants thrive in a cool, moist,
well tilled soil, rich in available plant food.
Those vegetables, which are grown for their edible
leaves, such as the cabbage, lettuce, spinach and others,
are all cool season crops. |
233. Warm Season Crops. — Almost all of the vege-
tables which are raised for their seed or fruits grow best
in the warm part of the season.
This rule has an important exception in the case of the
pea. The smooth pea is among the first vegetables to be
sown in the open ground. Wrinkled peas demand a
slightly warmer soil, though they may still be regarded
as cool season plants.
Beans, on the other hand, are very sensitive to cold
and can not be safely planted until the soil is warm and
“the oaks are in leaf.’
Sweet corn, like field corn, must not be planted until
the ground is warm and the danger of frost is past.
The tomato, egg plant and peppers, all related by the |
way, are warm, or even hot, season plants, and are easily
cut down by the frosts of either spring or fall.
The vine crops, such as the muskmelon, cucumber,
pumpkin, squash and water-melon, are all sensitive to
frost and require therefore a warm season and sunny
weather.
The sweet potato, which is a true root, succeeds best in
a loose, warm, sandy soil and in a warm, sunny climate.
234. Getting ahead of the Season. — Since many of
the garden crops can not be planted in the open ground
until late spring, — often not until nearly June in the
northern part of the United States —it is highly desir-
able to start the plants in some favorable and protected
place, from which they may be transplanted later to the
VEGETABLE GROWING 313
open ground. The place where plants are usually started
in this way is called a hotbed. |
Cabbage and lettuce may be started in these beds while
the ground is yet frozen. Radishes and lettuce may be
grown to maturity in them. Tomatoes may grow in these
beds to be several inches tall before the ground outside
is warm enough even to receive the seed. Muskmelons
and water melons may be started in inverted pieces of sod
in the hotbed and then transplanted when favorable
Fig. 143. — A hotbed.
weather comes on. In this way we can secure melons
several weeks earlier than we could otherwise.
EXERCISE 52
Object. — 'To learn how to make and manage a hotbed.
Procedure. — Select some place on or near the school
ground where the soil is well drained. A south slope is
preferable, and a gravelly or sandy soil drains better than
one of heavy clay.
Dig a pit two feet deep and as long and as wide as the
window frame which you can secure to cover the hotbed.
Build a frame out of lumber to hold your window sash,
allowing it to slope as shown in Figure 143.
~ Secure a load of fresh, horse barn litter, of which about
one half is bedding. Place this in a long, narrow pile three
or four feet wide and about the same height. This manure
314 SOILS AND PLANT. LIFE
should be moist, but not wet. It should be forked over!
every few days and kept moist by the addition of water as
necessary, as this treatment will cause it to begin heating.
When the pile has begun to steam uniformly, which usu-
ally takes place after about two weeks, it may be placed in
the pit which you have dug. This should be done by put-
ting in a shallow layer, tramping or packing it down well,
then-adding another layer, and so on until you have from
twelve to eighteen inches of well packed manure in the
bottom of the pit. This material will probably heat up
quickly, cool down in a few days, and then begin gradually
to heat again. When it begins to warm up the second
time, it should be thoroughly tramped and then covered
with about six inches of rich, mellow, sandy soil.
A thermometer should be placed in the soil; and when
the temperature has again fallen below ninety degrees
Fahrenheit, the seeds may be safely planted. We should
keep in mind at this time that the cool season plants re-
quire a lower temperature than the warm season crops.
Plant some radishes, lettuce, cabbage and tomatoes in
rows, and some melons in little squares of inverted sod.
The rows should be far enough apart to prevent crowding.
After the little plants come up, it is necessary to watch
the hotbed to see that they receive ventilation. The sash
should be raised, or taken off entirely, on warm days, and
closed down, or even covered over with old blankets during
cold nights and days. Then, too, the watering must be
done carefully. Apply enough with a watering pot to
keep the soil moist, but not wet. Perhaps the best time to
do this is about four o’clock in the afternoon. One good
watering every other day, or even less frequently, is better
than watering lightly, more often.
1For small hotbeds the manure may be taken from the barn
and placed directly in the hotbed.
VEGETABLE GROWING 315
The soil should be kept stirred to keep down the weeds
and to prevent baking. If the little plants are crowded,
some of them should be removed.
A cold frame is made in exactly the same way as a
hotbed, only that the pit, containing the heated manure,
is omitted.
From the hotbed, the plants may be taken to the cold
frame to be ‘ hardened” before they are finally trans-
planted into the garden.
Conclusion. — Write a brief account in your notebook
of the method of making a hotbed, the time required by
the various seeds to germinate and reach the surface,
and the management of it until the young plants are trans-
planted or otherwise disposed of.
235. In the Garden Proper. — Now that we have at-
tended to those vegetables which may be grown, or at
least started in the hotbed, let us turn our attention to the
garden itself.
The ground should have been fall plowed, or spaded,
and during the winter it should have had an application
of well rotted barnyard manure to provide plant food
and to make the soil more mellow when worked into the
ground.
Our next task is to make a plan of the garden in order
that we may know just where each vegetable is to be
planted. In making this plan, we must bear in mind that
good gardeners no longer use the old-fashioned beds, for
they are hard to weed and moreover cultivation must be
done largely by hand. Long, straight rows give a garden
a very neat appearance and permit the use of that great
labor saver, the wheel hoe.
Prepare in your notebook a plat of your home garden.
Make the scale such that one inch on the paper represents
twenty feet in the garden. The size should depend upon
A well managed garden one
hundred by one hundred fifty feet should supply five per-
sons.
SOILS AND PLANT LIFE
the number of people that are to be supplied by it with fresh
and winter vegetables.
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The following diagram will assist you in making your
L
plan:
VEGETABLE GROWING 317
936. The First Planting. — There are several of the cool
season crops that we shall want to plant at once. Among
them are:
Beets. — Hardly any other vegetables are more easily
raised than beets. If you plant the rows eighteen inches
apart in a loose, cool soil, and cultivate with the wheel
or hand hoe frequently to conserve the moisture and to
keep down the weeds, you will soon have a row of vigor-
ously growing young beet plants. You should pull out
enough of them to allow the remainder to stand six or eight
inches apart. The tops of the young beets which you re-
move will make excellent greens.
Later sowings may be made every two weeks into the
early summer. In the South, they are frequently used
even as a fall crop.
Cabbage. —If we have succeeded in raising stocky,
thrifty young cabbage plants in the hotbed, and have
transplanted them into a cold frame or perhaps a frame
covered with cloth so as to expose them to weather condi-
tions down nearly to freezing to make them hardy, we are
almost certain of very early, crisp cabbages.
At this time, the plants may be set in the open ground,
for they will endure considerable frost without injury.
The transplanting, however, should be done with care.
Near the close of the day, begin by opening the rich,
mellow soil with the hands or with a small garden shovel.
Place a plant in each hole, draw only enough dirt loosely
about it to hold it in place, and then pour in about half
a pint of water. The following morning, hoe the dirt
carefully about them, making the surface of the soil level.
This same method of transplanting should be followed
with tomatoes or any other plants which we may set out.
Cabbages should be set about two feet apart each way.
They should be cultivated very frequently to conserve the
318 SOILS AND PLANT LIFE
moisture and should be dusted if necessary with hellebore
to destroy the cabbage worms.
Late cabbage may be sown in open beds and trans-
planted to the fields as late as the middle of June. The
early cabbages should be used as soon as ripe or the heads
will tend to burst open.
Carrots. — These may be sown as soon as the soil is in
suitable condition in the spring. The earth must be
finely pulverized as the seeds germinate slowly. Inas-
much as the young plants are somewhat delicate, they are
easily overcome by weeds. |
Perhaps we should mark the carrot rows, which are to be
eighteen inches apart, by sowing a few radish seeds in them.
These will germinate quickly, breaking the crust over the
carrot seeds. Our task after this is simply to thin out the
young carrot plants until they stand from three to five
inches apart and to cultivate them with the wheel hoe to
keep out the weeds and to keep a mulch on the surface of
the ground.
Lettuce. — Few vegetables are appreciated any more
in the spring and early summer than fresh, crisp lettuce,
and, moreover, it is easily grown.
The plants may be started in the hotbed and trans-
planted into the garden if we wish ‘‘ to get ahead of the
season ’’; or the seeds may be sown directly into mellow,
rich soil. Frequent cultivation should be given to hasten
the growth of the crop.
Lettuce belongs to that group of plants called “ salad
crops,’ and a good salad depends upon the crispness of the
material used. It may be sown at intervals of two or three
weeks in any space available in the garden until the heat
of summer comes on. It may be sown again as a fall crop.
Onions. — Both the seeds and the sets of these vege-
tables may be planted. The latter produce the young,
VEGETABLE GROWING 319
green table onions so desirable in the early part of the
season, while the seed is used to grow the main crop for
fall and winter use. Onions from sets are easily and
quickly grown, but the crop grown from the seeds requires
special attention.
They are sown thickly in the row; and as soon asthe
little plants have pushed above the soil far enough to be
seen, they should be thinned out. As beginners, it will
perhaps be well for us to confine our efforts to raising
onions from sets. Only by strict attention to the soil,
which must be loose, rich and cool, by much tedious labor
in thinning, and by close and frequent cultivation, may
we expect to raise a crop of onions from the seed.
Parsnips. — These vegetables also revel in a cool, loose,
deep soil, in which their long, tapering roots may develop
without branching. The seed may be sown as soon as the
soil is warm in the spring and will occupy the ground
throughout the entire summer. In fact, most parsnips
are allowed to remain in the ground all winter as freezing
does not injure them. However, if one wants parsnips
for winter use, they must be dug in the fall and stored,
preferably in moist sand in a cool cellar. In planting
parsnips, as in the case of carrots, it is advisable to mark
the row by planting a few radish seeds in it. The distances
between the rows and between the plants in the row are
the same as those between carrots.
Potatoes. — You will notice by the home garden plan
shown in Figure 144, that only early potatoes were included,
and these were to be removed as soon as they were large
enough to be eaten, after which the space was to be de-
voted to celery. If enough potatoes are to be raised to
supply the entire family throughout the year, they should
usually be planted in a space outside the garden where they
may be cultivated by horse power.
320 SOILS AND PLANT LIFE
Karly potatoes may be started in the hotbed or in a box
of sandy soil in a window. If this is done, the best results
are obtained by planting whole potatoes of medium size
and removing all of the sprouts as they appear except
the strongest one. In three or four weeks, the plant will
have made thrifty growth. It may then be transplanted
Fig. 145. — Harvesting potatoes.
to the garden and new potatoes gathered from it several
days or even weeks before those which were planted as
dormant tubers on the same date in the open ground.
New potatoes begin to appear in the markets of the
northern cities in February and March. These are grown
in Florida. During the months from February to July,
northern markets are supplied by gardens in succession
VEGETABLE GROWING S21
from Florida northward.
plied by home gardeners.
In July, these markets are sup-
_ No matter where the grower lives, he knows that the
potato delights in a cool, rich, moist sandy loam. The
Florida man found his soil cool in January, the Wisconsin
man, in June. Each planted his tubers perhaps a little
more than three inches
deep, gave the plants
frequent, shallow till-
age, sprayed them
with Bordeaux mix-
ture (Exercise 37) to
keep the spores of dis-
ease from germinating,
and with lead arsenate
(Section 230) to kill
the insects.
The movement of
the potato harvest
from south to north
shows that the plant
thrives best in a cool
soil and accounts for
the fact that most of
our potatoes for win-
ter use are grown in
Maine, New York,
Fic. 146. — Bunch of radishes.
Michigan, Wisconsin, Minnesota and North Dakota.
Radishes. — Radish seeds have already been used to
mark the rows of carrots and parsnips, and these will
probably furnish enough radishes for early table use. If
not, more seed may be sown in nearly any place in the gar-
den. It will germinate quickly and the crop will thrive.
Tender, crisp radishes can be produced only when the
¥
322 SOILS AND PLANT LIFE
growth of the plants is rapid and continuous, and for this
reason, mellow, rich land is best. Successive plantings
of radish seed should be made at intervals of about ten
days until the hot weather comes on. A continuous
supply of these vegetables can easily be secured if the
season is at all favorable.
Spinach. — One of the most popular plants for greens
is spinach. We may sow the seed very early in the spring,
and in the cool, moist weather, the plants grow rapidly,
producing an abundant supply of fresh, green leaves.
Turnips. — The turnip is as easy to grow as the radish,
and the soil, season and cultural methods of the two plants
are the same.
Early turnips are sown as soon as the soil is warm enough
to receive them. The young vegetables are eaten fresh.
A fall crop, the main crop, is sown in the latter part of July,
or even later farther south, matures during the cool weather
of fall and is harvested before the temperature falls to
freezing.
A turnip or radish which grows and matures quickly is
crisp and sweet; one which grows slowly is woody and
bitter.
Peas. — Two types of peas should be recognized: those
with smooth seed coats and those whose seed coats are
wrinkled.
The smooth-seeded varieties, such as the ‘ Alaska ”’
or “ First and Best,’’ may be planted with the earliest of
the cool season crops, while the wrinkled varieties, such as
“ Nott’s Excelsior,’ should not be planted until two weeks
later, or even more, as the seed will rot if cold, wet weather
comes on.
The early varieties are usually rather low growing and
require no support for their pods, while the late varieties
tend to form vines and produce the best pods when sup-
VEGETABLE GROWING 323
ported by brush or wire netting. These tall varieties are
sown in rows three or four feet apart, while the “ dwarf”
varieties may be planted as near together as eighteen
inches. The seeds of both kinds are planted about two
inches apart in the row and covered about two and one
half inches deep.
237. When the Danger of Frost is past. — In making our
plans for the warm season crops, we may study first, those
plants which were started in
the hotbed, and second, those
whose seeds are planted di-
rectly in the warm, open soil.
Tomatoes. — These plants
need a long, warm growing
season and therefore thrive
bestin the South. By start-
ing the plants under glass,
however, and transplanting
them to cold frames later,
stocky, vigorous plants may
be produced, which are well on
their way by the time warm
weather arrives. Inthis way,
tomatoes are grown even
north of the Canadian line.
In any locality, the best to-
matoes are grown on a rich,
ey soil. In addition to Fig. 147. — Pruned tomato
this, some means must be pro- vines.
vided of keeping the vines up
out of the dirt. A wooden or wire frame may be placed
under the vines-to hold them up, or they may be pruned to
a single stem and tied up to a stake, orlath. In fact, some
U. S. Dept. of Agriculture.
324 SOILS AND PLANT LIFE
of the finest tomatoes are raised by the latter method. The
pruning checks the growth, which induces earlier fruiting
and permits the growth of more vines in a row of given
length. Ifthe vines are not pruned and they are found
making plant growth at the expense of fruit growth, the
terminal buds should be pinched out.
Sweet Potatoes. — In the South,
sweet potatoes are called potatoes,
while other potatoes are called
Irish potatoes. This goes to
show that the sweet potato is
really most at home in the warm,
sandy soil south of the Ohio and
Missouri rivers.
Young plants may be secured
by planting the sweet potatoes,
either whole or split once length-
wise, in the hotbed and covering
them with four or five inches of
sand. When the plants have
attained some size, and the soil is
warm, they may be transplanted
to ridges in the open ground.
These ridges are usually made
three feet apart, and the plants
on the ridges are set from one to
two feet apart. Special cultiva-
tors, or the hand hoe, are used to keep the soil free from
weeds.
Celery. — One of the most unsatisfactory crops to at-
tempt to grow is celery.
The seeds start very slowly in the hotbed, — the plants
are delicate, can not endure hot, dry winds, and they
demand a cool, very rich, and very moist soil. Moreover,
Fic. 148. — A roasting ear.
VEGETABLE GROWING o2e
after careful tillage, the plants must still be blanched by
banking earth or leaning boards against the stems.
If by careful preparation of the soil, by transplanting
the small plants to level ground or to the bottom of a fur-
row, by painstaking cultivation and banking, you succeed
in raising celery, you will
often find the home-
grown product superior
to that purchased at the
market.
Celery is grown in im-
mense fields of reclaimed
muck or swamp land in
Michigan and California.
Sweet Corn. — Like
other corn, this is a
warm season crop, de-
manding a great deal of
sunlight, moisture and
available plant food.
Sweet corn, or sugar
corn, In common with
other vegetables grown
for their seeds, is never
transplanted. We
should remember, how-
ever, that some varie-
ties mature more quickly
than others and endure a
little more cold weather.
Our first planting, which
should not be made until
Fig. 149. — Lima beans.
the soil is fairly warm, should be of the small-stalked
varieties, such as the “‘ Early Minnesota,” the ‘‘ Golden
326 SOILS AND PLANT LIFE
»]
Bantam,” or the ‘“ Peep-o’-Day.’’ A week or two after
the first planting, some such variety as the ‘ Country
Gentleman’’ may be planted. Late plantings should be
of the large-stalked, large-yielding, sweeter varieties of the
type of ‘‘Stowell’s Evergreen.” The cultivation of sweet
corn is similar to that of field corn.
Beans.— These are divided into two classes, string
beans and Lima beans. While both are warm season
Fig. 150.— Young melon plants are this much ahead of the season if
started in overturned sods or boxes.
crops, and can not be planted until the danger of frost is
past, the Lima beans require even a higher temperature
than the others. In fact, it is best to delay the planting
of the Limas until fully two weeks after it is deemed safe
to plant the string beans.
Of the string beans, there are two classes, the green and
the wax beans. Both are easily grown, requiring only
good tillage, and if the ‘“‘ vining”’ varieties are raised,
a support, such as is provided for tall peas.
Dwarf Lima beans are now grown, although less than
thirty years ago only the pole Limas were known. The
dwarf, small-seeded varieties are rather to be preferred
for a home garden, though an Indian “‘ wigwam”’ built
VEGETABLE GROWING BOA A
of slender poles, or even a single pole, driven into the
ground, will support the large Limas which grow from
eight to ten feet tall and produce heavy crops of seed.
Vine Crops. — Cucumbers, watermelons, muskmelons,
pumpkins and squashes, which are known as vine crops,
may all be considered together, for in their manner of
growth, as well as in their soil and moisture requirements,
they are very much alike.
Copyright The Gerlach-Barklow Co.
Fig. 151. — Ready for the table.
Pumpkins and squashes are usually planted in the open
ground after the danger of frost is past. We are not usu-
ally concerned as to when they will ripen, for we think of
them in connection with the autumn frosts.
On the other hand, we are anxious to have watermelons
and muskmelons mature as early in the season as possible.
In starting either melons or cucumbers; our hotbed again
comesinto use. By making paper boxes of heavy cardboard,
by using wooden strawberry boxes and filling them with rich
328 SOILS AND PLANT LIFE
earth, or even by making use of small squares of sod, turned
upside down, a seed bed is secured. Here the plants may
grow for several weeks; and when the ground has become
warm enough, they may be taken to the field and trans-
planted, care being taken to avoid disturbing the roots.
The precautions to be taken in growing vine crops are:
(1) Provide well drained, rich soil; and for watermelons,
choose a sandy one if possible. .
(2) Plant the seed in hills far enough apart to allow the
vines to spread. The distances should vary from four by
four feet for cucumbers to eight by eight feet or more for
watermelons.
(3) Thin out the plants in each hill, leaving only three
or four of the strongest ones.
(4) Remove the first plants that show melon bugs or
lice. If this does not check them, spray with Black Leaf
40. (Section 230.)
(5) If the striped beetles appear, cover the vines with
small frames of mosquito netting, spray with dilute Bor-
deaux mixture and lead arsenate, or dust lightly once or
twice a day with sifted ashes, gypsum or other fine powder.
(6) Cultivate between the rows frequently until the
vines become too long. Then use the hoe.
QUESTIONS
1. Divide vegetable crops into two groups according to the
season in which the seed is planted. Name five vegetables of
each group.
2. Tell fully how to make and manage a hotbed.
3. What is a cold frame and how is it made?
4. Tell briefly how to plant cabbages in the hotbed, harden
them in the cold frame and transplant them into the garden.
5. Divide peas into two classes and tell when each should be
sown.
6. Are onion seeds rather to be chosen than sets for the home
garden? Why?
VEGETABLE GROWING 329
7. How may you secure ‘extra early’’ potatoes? Where
is most of our winter supply of potatoes grown? Why?
8. What two classes of beans do we have and when should
each be sown?
9. Tell briefly how to grow tomatoes in the hotbed, how to
transplant them, and how to prune them to a single vine.
10. Name five rules to follow in growing vine crops.
CHAPTER XXIII
PERMANENT AGRICULTURE
TuE land in the United States of America has been called
the “ floor space of the nation.”’ The work for three hun-
dred years has been to occupy this floor space. Forests
have been cut down, swamps have been drained, and
streams have been spread out to furnish moisture for fields
in places where little came from the clouds.
So long as there was new land to occupy, — rich fields
awaiting the plow, — there was food in plenty and to spare.
Now, however, there is little new land to occupy, and the
number of mouths that must be fed continues to increase.
Land can no longer be abused and then thrown back
upon a generous Nature to repair the waste of man.
The soil has been compared to money in the savings
bank, upon which the interest only may be drawn each
year. If more than this is wanted, we begin to draw upon
the principal. That is to say, a certain amount of plant
food — nitrogen, phosphorus, potassium, ete.—is un-
locked each year by the rain, the frost and the unseen or-
ganisms of the soil.
Certain plants take out more of a given element than
do others. While clover, for example, is taking out a
great deal of potash, the store of nitrogen in the soil is
increasing ; and when corn later begins to draw upon the
nitrogen, the drain upon the potassium is lessened.
It is definitely known just how much of each element
is taken out of the soil by each crop. It therefore
330
PERMANENT :AGRICULTURE BS alk
becomes a matter of good farming to restore to the land
in some way that which is removed from it by the crops
grown in it.
We may, it is true, increase our crop yields by the selec-
tion of better seed, by the selection of superior varieties,
by improved methods of cultivation, or otherwise; but a
permanent agriculture, upon which the future prosperity
of the nation depends, rests finally upon the maintenance
of fertility of the soil.
238. The Result of selling Crops from the Land. — The
fertility of the soil is very largely, though not altogether,
a matter of the presence in it of those elements which
plants must have in order to make healthy growth, — par-
ticularly nitrogen, phosphorus and potassium. (Section 7.)
Let us suppose that an acre of ground produces a crop
of fifty bushels of ear corn. This amount of corn contains
approximately fifty pounds of nitrogen, nine pounds of
phosphorus and _ fifteen pounds of potassium; and if the
crop is sold, these three elements will be lost from the farm
in the amounts named.
The small grains do not remove so much fertility from
the soil as does corn, since the amount of food material
which they produce is actually much less. Thus a crop
of twenty bushels of wheat per acre takes twenty-four
pounds of nitrogen and about five pounds each of phos-
phorus and potassium from the land, while a fifty-bushel
crop of oats removes from the soil approximately tharty-
two pounds of nitrogen, s?x pounds of phosphorus and
eight pounds of potassium.
Timothy may remove even more of the elements of
fertility from the soil than do the small grains. A crop
yielding one and one half tons of hay per acre, takes
about thirty-seven pounds of nitrogen, seven pounds of
aoe SOILS AND PLANT LIFE
phosphorus and twenty dite pounds of potassium from the
land.
In a very true sense, then, the farmer who sells his crop
to others is really selling the fertility of his soil; or we
may say that, little by little, he is selling the land itself.
To continue such a practice year after year must inevitably
result in the gradual exhaustion of the soil. It is chiefly
due to this fact that much of the land of the older sections
of the country has become, as we say, “‘ worn out,”’ by
which we mean that it has reached the stage at which it
will not produce crops that will yield a profit above the
actual cost of care and cultivation.
239. How the Three Important Elements of Fertility
may be restored to the Soil. —
Nitrogen. — The store of nitrogen in the soil may be in-
creased in three ways:
(1) By growing legumes.
(2) By the application of barnyard manure.
(3) By the application of commercial fertilizers.
How the bacteria which live on the roots of legumes take
nitrogen from the air and convert it into a form that
plants can use was explained in Section 180. The actual
amount of nitrogen that is received from the air in this
way by the legumes varies with the different plants. A
crop of red clover, sweet clover or crimson clover, yielding
one and one half tons of hay per acre, receives from the
air as arule between sixty and seventy pounds of nitrogen ;
a cutting of alfalfa or cowpeas, yielding the same amount
of hay per acre, contains usually from seventy to eighty
pounds of nitrogen which has been taken from the air;
and it follows that if a crop of any one of these plants which
would yield a ton and a half of hay per acre were plowed
under, nitrogen would be added to each acre of the soil
PERMANENT AGRICULTURE 339
in the amount named. To cut the hay and sell it from the
farm, however, would give a far different result. In this
case, little or no nitrogen would be added to the soil by the
iegume since the amount contained in the roots and stubble
is usually about the same as that which these plants have
actually drawn from the soil itself; but on the other hand
the land would lose heavily in phosphorus and potassium,
owing to the fact that legumes take large amounts of these
elements from the soil.
By the application of barnyard manure, not only nitro-
gen, but also phosphorus and potassium may be added to
the soil. A ton of ordinary barnyard manure contains
about ten pounds of nitrogen, two pounds of phosphorus
and eight pounds of potassium. If we compare these
figures with the amounts of the same elements removed
from an acre of ground by a fifty-bushel crop of corn, we
see that it would require the application of about five
tons of manure per acre to replace the nitrogen removed
by a single corn crop.
The use of commercial fertilizers to restore nitrogen
to the soil is much more general in the older sections of
our country than in the newer parts where the virgin
fertility has not been altogether exhausted and where the
clovers may be more easily grown. The fertilizers which
are commonly used to add nitrogen to the soil are as fol-
lows:
Sodium nitrate, called also Chile saltpeter. Each
hundred pounds of this product contains from fifteen to
sizteen pounds of nitrogen. It should be applied to the
land after plants have begun to grow, as it dissolves readily
and is soon leached or washed out of the soil. It should
be mixed with three or four times its weight of soil, as
otherwise it may injure the growing plants. The amount
used varies from one hundred to two hundred pounds
334 SOILS AND PLANT LIFE
per acre; and to secure the best results, this is not all
applied at one time but two or three applications in smaller
amounts are made during the growing season.
Ammonium sulfate, which contains about twenty-one
per cent of nitrogen, is often used. It is quite effective ;
but a rather serious objection to it is found in the fact
that it apparently tends to leave the soil acid.
Calcium nitrate, which is manufactured chiefly in
Norway, and which contains about twelve per cent of
nitrogen, is a highly satisfactory fertilizer save for the
fact that the nitrogen in it is rather more expensive than
that in the products named above.
Fish fertilizers, consisting usually of the dried, ground
bodies of the menhaden, are often used with excellent
results. They contain from ezght to eleven per cent of
nitrogen as a rule and also from one to two per cent of
phosphorus.
Phosphorus. — Unlike nitrogen, this element can not
be restored to the soil by growing legumes or any other
special crops. Rather it can be added only in the form
of barnyard manure, as already stated, or in the form of
commercial fertilizers.
The commercial fertilizers commonly used for this
purpose are: |
Ground phosphate rock, or floats. This rock is quarried
in Florida, the Carolinas, Tennessee and some of the
western states. It is also called rock phosphate or in-
soluble phosphate of lime. It contains from eleven to
thirteen per cent of phosphorus. It is insoluble in water
and for this reason could not be used as a fertilizer at all
but for the fact that it is very gradually dissolved by the
acids which are formed by the decay of the humus in the
soil. It is usually applied with barnyard manure. Its
effects are not quickly seen as a rule but extend over a
PERMANENT AGRICULTURE Be,
period of several years, increasing during the first three or
four years.
Calcium acid phosphate, called also simply acid phos-
phate, soluble phosphate of lime, one lime phosphate,
superphosphate, etc. It is soluble in water and hence
gives quick results though the effects are not seen so long
as in the case of floats. An average sample contains
about seven per cent of phosphorus.
Ground or steamed bone, which is chemically nearly the
same as floats, and which contains from ten to eleven per
cent of phosphorus in addition to about two and a half
per cent of nitrogen.
Basic slag, a by-product of the manufacture of steel,
is considerably used as a source of phosphorus. It con-
tains from six to nine per cent of this element. It dis-
solves very slowly and hence should be finely ground.
Potassium. — Most new soils contain enough potassium
to supply the needs of plants for a very long time. How-
ever, sandy soils, or newly drained swamp land, may be
deficient in this element as well as those soils which
have been long under cultivation. It may be restored
only in the form of barnyard manure or commercial
fertilizers.
The chief commercial fertilizers containing potassium
are :
Potassium chloride, called also muriate of potash.
It gives satisfactory results for ordinary crops; but pota-
toes, tobacco, sugar beets and other plants which use
much potassium appear to be injured by the chlorine
present.
Potassium sulfate, which is of special value for those
crops which are injured by the chloride.
Kainite, which contains from ten to twelve per cent of
potassium in the form of both chloride and sulfate.
336 SOILS AND PLANT LIFE
240. The Care and Importance of Barnyard Manure. —
About eighty per cent of the essential elements contained in
the grain and hay fed to live stock is returned in the excre-
ment. If the manure, both solid and liquid, is carefully
preserved and returned to the soil without loss, only
about twenty per cent of the fertility contained in the crops
fed is lost from the land. Usually, however, the manure
is not properly handled; and as a result, about one third
of the fertility which it contains is lost. In this case,
but little more than half of the fertility taken from the
soil in the crops gets back to it again.
It follows that no farm can maintain its fertility indefi-
nitely simply by feeding the crops which it produces to
live stock and returning the manure to the land. If the
fertility is to be maintained by means of barnyard manure,
it is necessary either to secure some from an outside source
to be added to that which the farm produces or to purchase
supplementary feeds or grain from others and feed them
on the farm.
The chief losses of fertilizing elements from manure
occur in three ways:
(1) The manure is not protected from rains, and much
of the fertility which it contains is leached, or washed out
of it. This may be prevented by protecting it by a suit-
able roof or by applying it at once to the fields.
(2) The liquid manure is allowed to escape. Pound
for pound, it is more valuable than the solid manure, owing
to the large amount of nitrogen and potassium which it
contains. Sufficient bedding should be used to absorb
all of it, or it should be drained into a cistern to be ap-
plied later to the land.
(3) Much loss results from fermentation, by which
nitrogen escapes in the form of ammonia. This fermenta-
tion may be detected by the heating and steaming of the
PERMANENT AGRICULTURE ze
manure heap or even by the odor of ammonia about the
barnyard. It is due to bacteria which can exist only in
the presence of air; and if the manure heap is kept com-
pact and moist, it may be easily prevented.
Notwithstanding the necessity of supplementing barn-
yard manure with legumes or with other fertilizers, it is
still true that it is by far the most valuable fertilizing
agent known. The farm, on which all crops produced
are fed to live stock and the manure carefully preserved
and returned to the land, will continue profitable produc-
tion from three times to five times as long as will one
from which all crops are sold. It is for this reason that
“stock” farms are almost invariably found to be more
productive than adjoining ‘ grain” farms. It follows
of course that there should be enough live stock on every
farm to consume all, or practically all, the grain and forage
which it produces.
EQUIPMENT
A list of apparatus, which will assist the student in per-
forming the exercises outlined in the foregoing lessons, is
given below: !
20 12-0z. Gas Bottles, or Wide-mouthed Preserve Jars.
6 Small Steel or Iron Frying Pans.
1 Trip Seale with Rider.
1 Set Avoirdupois Weights, 1 lb. to 4 oz.
1 Set Metric Weights, 1 Kg. to 5g.
20 Tin Cans, No. 3, with lids and bottoms removable.
20 circular pieces Screen Wire, slightly larger than lids of cans
above.
2 Thermometers, Soil or Dairy preferred.
20 Test Tubes, 6 x 2’’, with corks to fit.
1 Glass Graduate, 100 c.e.
20 One-hole Rubber Stoppers to fit test tubes above.
20 Glass Tubes, 2’’ in diameter and 15” long; or ordinary lamp
chimneys may be used.
5 Racks to hold tubes above.
10 Wire Baskets, factory- or home-made of screen wire, 6’ in
diameter and 6” deep.
6 Books Blue Litmus Paper.
6 Books Red Litmus Paper.
4 Medium Size Alcohol Stoves.
1 Galvanized Iron Pail with Vertical Sides, capacity 3 gals.
6 Granite or Agate Pans, capacity 2 qts.
12 Hand Lenses.
1 gal. Denatured Alcohol.
8 oz. Saturated Iodine Solution.
4 lbs. Paraffin.
1 This list includes enough apparatus for twenty students, working in groups of
four. ;
338
EQUIPMENT 339
1 lb. 40% Formalin.
5 lbs. Blue Vitriol, or Copper Sulfate.
5 Ibs. Fresh Unslaked Lime, to be kept in fruit jars, or other-
wise protected from the air.
1 lb. Beeswax.
i 1b. Raw Linseed Oil.
6 Small Muslin Sacks for holding soil samples.
Seeds of Rough Rice, Teparie Beans, Wax Beans, Corn,
Wheat, and Oats.
+ Ib. Absorbent Cotton.
24 pieces No. 14 Wire, 8” long.
6 Safety Razor Blades.
PUBLICATIONS
No list of bulletins is here suggested, inasmuch as the
ones now available may be out of print at any time; and
moreover, new ones are being continually added to the
list.
The list of available publications from any station
may be secured at any time; and it is suggested that
if bulletins are needed, such a list be secured from the
station or stations as desired.
U. S. DEPARTMENT OF AGRICULTURE
BuREAU OF PUBLICATIONS
ALABAMA. — College Station: Auburn.
Canebrake Station: Uniontown.
Tuskegee Station: Tuskegee Institute.
ALASKA. — Sitka.
ARIZONA. — Tueson.
ARKANSAS. — Fayetteville.
CALIFORNIA. — Berkeley.
Co.Lorapbo. — Fort Collins.
ConneEcTIcCUT. — State Station: New Haven.
Storrs Station: Storrs.
DELAWARE. — Newark.
FLoripa. — Gainesville.
Geroraia. — Experiment.
Guam. — Island of Guam.
Hawai. — Federal Station: Honolulu.
Sugar Planters’ Station: Honolulu.
IpaHo. — Moscow.
Iuuinoris. — Urbana.
InpIANA. — La Fayette.
Iowa. — Ames.
Kansas. — Manhattan.
Kentucky. — Lexington.
Louisiana. — State Station: Baton Rouge.
340
PUBLICATIONS 341
Lovis1ANa. — Sugar Station: Audubon Park, New Orleans.
North Louisiana Station: Calhoun.
Maine. — Orono.
MaryLanp. — College Park.
MassacuHusetts. — Amherst.
Micuiean. — East Lansing.
Minnesota. — University Farm: St. Paul.
Mississippi. — Agricultural College.
Missouri. — College Station: Columbia.
Fruit Station: Mountain Grove.
Montana. — Bozeman.
Nesraska. — Lincoln.
Nevapba. — Reno.
New Hampsuire. — Durham.
New Jersey. — New Brunswick.
New Mexico. — State College.
New York. — State Station: Geneva.
Cornell Station: Ithaca.
NortuH Carouina. — College Station: West Raleigh.
State Station: Raleigh.
Nort Dakora. — Agricultural College.
Outro. — Wooster.
OKLAHOMA. — Stillwater.
OREGON. — Corvallis.
PENNSYLVANIA. — State College.
State College: Institute of Animal Nutrition.
Porto Rico. — Federal Station: Mayaguez.
Insular Station: Rio Piedras.
RuopeE [suanp. — Kingston.
SoutH Carouina. — Clemson College.
SoutH Daxkora. — Brookings.
TENNESSEE. — Knoxville.
Trxas. — College Station.
Urau. — Logan.
VERMONT. — Burlington.
Vira@inia. — Blackburg.
Norfolk: Truck Station.
WASHINGTON. — Pullman.
West Virainia. — Morgantown.
WIsconsin. — Madison.
Wyominc. — Laramie.
INDEX
Acid soil, 252.
effect on clovers, 252.
litmus test for, 254.
how corrected, 258.
Agriculture defined, 287.
Air, amount in soil, 25.
in soil, effect upon temperature,
ol
space in soil, how increased, 25.
why necessary in soil, 25.
Alfalfa, 246.
methods of culture, 267.
range of, 246.
Alsike, 249.
methods of culture, 270.
range of, 249.
Anthers defined, 108.
Apple, age of bearing wood,
295.
how pruned, 302.
298,
Bacteria, how added to the
260.
necessary to clovers, 255.
Barley, climatic range, 221.
preparation of seed bed for,
uses of, 221.
Barnyard manure, care of, 336.
composition of, 333.
how fertility is lost from, 336.
value of, 333, 337.
Bast fibers, 105.
Beans, how grown, 326.
Beets, how grown, 317.
Bermuda grass, 234.
advantages of, 234.
disadvantages of, 234.
how propagated, 234.
range and character of, 234.
soil,
Blue grass, 230.
advantages of, 232.
character and value, 230.
disadvantages of, 232.
seeding of, 231.
Bordeaux mixture, how made, 131.
how used, 131, 309.
strength for stone fruits, 132.
Bread mold, 126.
Brome grass, 233.
advantages of, 233.
disadvantages of, 233.
value of, 233.
Cabbage, how grown, 317.
Calyx defined, 108.
Cambium layer defined, 104.
Carbon, 10.
Carbon dioxide, 69.
given off by germinating seeds,
69.
test for, 69.
Carrots, how grown, 318.
Celery, how grown, 324.
Cereals defined, 203.
leading in various countries, 203.
Chaffiness defined, 156.
Cherry, pruning of, 301.
age of bearing wood, 295.
Cloddy fields, cause of, 39.
Clover, crimson, 245.
range of, 245.
Japan, methods of culture, 270.
Japan, range of, 242.
red, methods of culture, 266.
red, range of, 248.
sweet, methods of culture, 269.
sweet, range of, 248.
white, methods of culture, 270.
Blackberry, age of bearing wood, | Clovers, causes of failure, 250.
297.
how pruned, 297, 301.
effect of acid soils, 252.
effect of careless seeding, 256.
343
344
Clovers (continued).
effect of drouths, 257.
effect of friendly bacteria, 255.
effect of lack of humus, 255.
effect of lack of phosphorus, 254.
effect of nurse crop, 256.
hard seeds of, 264.
methods of seeding, 261.
how to succeed with, 258.
why sown with grasses, 236.
Cold frame, how made, 315.
Color of soil, effect on temperature,
34.
Corm defined, 229.
INDEX
seed bed in sod ground, 182.
seed bed in stubble ground, 185.
replanting, 190.
sensitiveness to climatic changes,
a2:
soil requirements of, 154.
substitute crops for, 198.
sweet, how grown, 324.
unsoundness in, how recognized,
aes
uses of, 149.
why barren stalks are avoided, 55.
why stalks with suckers are
avoided, 55.
Corn, acreage in United States, 149. | Corolla defined, 108.
Belt, how pushed northward, 54. | Cotton, how ginned, 280.
climatic requirements of, 152.
cultivation of, 191.
depth of cultivation, 193.
desirable characters of ear, 157.
desirable characters of kernel, 162.
desirable characters of stalk, 53.
desirable butt described, 160.
desirable shape of ear, 159.
desirable size of ear, 158.
desirable size of kernels, 163.
desirable shape of kernels, 163.
desirable tip described, 161.
detasseling of, 116.
distribution of, 150.
effect of climate on type, 151.
seed, how dried, 172.
seed, how graded, 179.
seed, how stored, 173.
seed, how tested, 174.
seed, selection in field, 169.
frequency of cultivation, 195.
harvesting of, 196.
ideal seed bed for, 181.
immaturity in, how recognized,
Haar
listed, cultivation of, 200.
moisture requirements, 152:
planting, depth of, 188.
planting, distance between rows,
189.
planting, methods of, 185.
planting, number kernels in hill,
189.
planting, time of, 187.
seed bed in cornstalk ground, 184.
how harvested, 280.
importance of, 275.
methods of culture, 277.
plant described, 276.
range of, 275.
Cottonseed meal, 282.
Cotyledon defined, 62.
effect of removing, 74.
Cowpeas, methods of culture, 271.
range of, 245.
Cross-fertilization by hand, 113.
Cross-fertilization defined, 113.
Cucumbers, how grown, 327.
Cultivation of corn, depth of, 193.
Cultivation of corn, frequency of,
195.
Cultivation of listed corn, 200.
Cuttings, 138.
Decay, cause of, 126.
Dicotyledon defined, 62.
Dicotyledons, flowers of, 108.
roots of, 84.
seeds of, 63.
Diseases, cause of, 126.
how prevented, 128.
Drouths, effects on clovers, 257.
Drying seed corn, 172.
Dura, 198.
Earthworms, work done by, 9.
Elements, essential, 10.
Embryo, 62.
enemies of, 46.
how protected, 46.
INDEX
Endosperm, 63.
effect of removing, 73.
Fertilization, cross-, 113.
defined, 113.
self-, 113.
Feterita, 198.
Fiber crops, leading, 274.
Fibro-vascular bundles, 101.
Filament, 108.
Flax, methods of culture, 282.
methods of handling, 283.
range of, 282.
value of products, 284.
Flowers of dicotyledons, 108.
of legumes, 238.
of monocotyledons, 109.
pistillate, 110.
staminate, 110.
fertilized by insects, 111.
fertilized by wind, 111.
Food, stored in leaves, 96.
stored in roots, 87.
stored in seed, 92.
stored in stems, 137, 229.
made from starch, 92.
source of all, 92.
travels how from leaves to roots,
103.
Formalin, use of, for oat smut, 128.
use of, for potato scab, 130.
Frost, prevention of injury by, 305.
Fruit buds, age of wood bearing,
295.
Fruit buds, conditions
formation of, 293.
how and when formed, 292.
Fruit, gathering and storing, 309.
Fruits, places of origin, 287.
Fruit trees, cultivation of, 291.
distances between, 289.
how developed when young, 288.
training of, 292.
how planted, 290.
favoring
Garden, plan of, 316.
Germ defined, 46, 62.
Germination, conditions of, 64.
optimum temperatures for, 67.
Girdling trees, effect of, 103.
Glacier defined, 1.
345
Glumes, 109.
Grading of seed corn, 179.
Grafting wax, 139.
Graft, cleft, 142.
whip, 140.
Grape, age of bearing wood, 296.
cultivation of, 291.
method of planting, 291.
method of pruning, 300.
Grasses, characteristics of, 224.
’ leading cultivated, 227.
habit of growth, 226.
range of each, 236.
Heat from germinating seeds, 71.
Hemp, how handled, 284.
range of, 284.
Hessian fly, 210.
Horticulture defined, 287.
Hotbed, 313.
Humus defined, 5.
effect on air space in soil, 29.
effect on soil structure, 37.
effect on water-holding capacity,
5%
how added to soil, 259.
necessary to clovers, 255.
Hydrogen, 11.
Hypocotyl, 62.
Inoculation, defined, 260.
method of, 260.
Insects on vine crops, how com-
bated, 328.
prevention of injury by, 307.
Kafir corn, 198.
cultivation of, 200.
planting of, 200.
Leaf likened to a mill, 90.
Leaves, functions and uses, 89.
storage of food in, 96.
Legumes, as nitrogen gatherers, 240.
benefits of, 239.
characteristics of, 238.
flowers of, 238.
range of, 242.
securing maximum benefits from,
Par pes
Lettuce, how grown, 318.
346
Limestone, how applied to soil, 259.
uses of, 258.
Linseed meal, 284.
Linseed oil, 284.
Loam soil defined, 4.
Manure, effect on air space, 29.
Mice, prevention of injury by, 305.
Milo maize, 198.
Moisture, film or capillary, 19.
hygroscopic, 19.
in soil, effect on temperature, 33.
necessary for germination, 65.
requirements of corn, 152.
why injurious to stored seeds,
Lasal mee
Monocotyledon, defined, 62.
seeds of, 63.
flowers of, 109.
leaves of, 225.
roots of, 83.
stems of, 101.
Mulch, dust, 42.
use of, 23.
Muskmelons, how grown, 327.
Nitrogen, 11.
amount in barnyard manure, 333.
amount in corn, 331.
amount in oats, 331.
amount in timothy, 331.
amount in wheat, 331.
commercial fertilizers contain-
ing, 332.
how added to soil by legumes,
240.
how restored to soil, 332.
how lost in process of burning, 92.
Nodules on roots, 240.
Nurse crop, defined, 256.
influence on clovers, 256.
crops suitable for clovers, 260.
Oatmeal, 219.
Oats, character of crop, 213.
advantages of stacking, 219.
how planted, 215.
how shocked, 218.
loose smut of, 127.
Oats, seed, desirable characters of,
216.
INDEX
seed bed for, 215.
seed, selection of, 216.
spring, 214.
used for hay, when cut, 218.
uses of, 219.
varieties of, 214.
when harvested, 218.
winter, 214.
Onions, how grown, 318.
Orchard, location of, 289.
Osmose, defined, 78.
law of, 78.
Ovule defined, 113.
Oxygen, 11.
necessary for germination, 65.
Palea defined, 109.
Parsnips, how grown, 319.
Peach, age of bearing wood, 296.
development of young tree, 144.
how pruned, 301.
Peas, how grown, 322.
Petals defined, 108.
Phosphorus, 11.
amount in barnyard manure, 333.
amount in corn, 331.
amount in oats, 331.
amount in timothy, 331.
amount in wheat, 331.
commercial fertilizers
ing, 334.
necessary to clovers, 254.
Photosynthesis defined, 89.
Pistil defined, 108.
Planting corn, methods of, 185.
time of, 187.
depth of, 188.
Plants, classes according to useful
parts, 144.
how propagated, 124.
life cycle of, 44.
two great classes of, 62.
Plowing under stubble and clods, 21.
Plum, age of bearing wood, 295.
pruning of, 301.
Plumule defined, 62.
Pollen, defined, 108.
how carried from plant to plant,
1Sieh,
Pollination defined, 111.
Potassium, 12.
contain-
INDEX
Potassium (continued).
amount in barnyard manure, 333.
amount in corn, 331.
amount in oats, 331.
amount in timothy, 331.
amount in wheat, 331.
commercial fertilizers
ing, 335.
how restored to soil, 335.
Potatoes, how grown, 319.
sweet, how grown, 324.
Propagation, by budding, 142.
by bulbs, 136. .
by grafting, 139.
by layers, 135.
by runners, 134.
by seeds, 133.
by spores, 124.
by suckers, 135.
by tip layers, 135.
Protein, in legumes, 242.
effect of feeding, 120.
Pruning, methods of, 299.
why necessary, 298.
precautions necessary, 304.
Pumpkins, how grown, 327.
contain-
Rabbits, prevention of injury by,
305.
Radicle defined, 62.
Radishes, how grown, 321.
Raspberry, age of bearing wood, 297.
how pruned, 301.
methods of cultivation, 291.
Redtop, advantages of, 233.
disadvantages of, 233.
range and character of, 232.
Rice, how cared for, 223.
how harvested, 223.
how planted, 223.
how prepared for use, 223.
production of, in U. S., 222.
seed bed for, 222.
soil requirements of, 222.
uses of, 224.
Root hairs, origin of, 81.
Roots, absorbing, 80.
anchorage, 80.
anchorage, origin of, 81.
benefits of, 88.
functions of, 77.
347
food stored by, 87.
how minerals are dissolved by, 79.
how tips are protected, 82.
of dicotyledons, 84.
of monocotyledons, 83.
rapidity of growth in
stages, 76.
region of growth, 82.
why moisture enters, 77.
Rotation, benefits of, 29, 85.
defined, 206.
that is often recommended, 206.
Rye, soil requirements of, 221.
uses of, 221.
early
Sands, shifting of, 85.
Sappiness defined, 156.
Seed analysis, 261.
Seed bed for barley, 221.
for corn, 181.
for corn, how prepared, 182.
for oats, 215.
for rice, 222.
for wheat, 207.
for wheat, how prepared, 206.
Seed collection, how made, 50.
defined, 62.
functions of, 46.
Seedling, defined, 75.
vigor of, how determined, 74, 76.
Seeds, effect of moisture upon, 59.
enemies of, 46.
explosive or creeping, 48.
first factors determining vitality
of, 60.
how scattered by man, 49.
how scattered by nature, 46.
how:scattered by animals, 48.
how scattered by water, 47.
how scattered by wind, 47.
selection of, by man, 52.
selection of, by nature, 52.
size of, effect on seedlings, 73.
storage of, by man, 58.
Self-fertilization defined, 113.
Sepals defined, 108.
Shocking oats, methods of, 218.
Sieve tubes, 103.
Silt, 4.
Soil acidity, effect on clovers, 252.
test for, 254.
348
Soil binders, 85.
Soil, how water is lost from, 13.
how made, 1.
how mixed and laid down, 2.
Soil making, réle of animals in, 8.
role of plants in, 7.
Soil material, two sources of, 5.
Soil names, 4.
Soil requirements, of corn, 154.
structure defined, 36.
texture defined, 36.
Soil, what it is, 1.
Sorghums, characteristics of, 199.
Soy beans, 249.
methods of culture, 271.
Spinach, how grown, 322.
Spores causing disease or decay,
126.
how entrance is favored, 133.
how spread, 127.
how prevented from spreading,
128.
summer, 130.
winter, 130.
Spring defined, 17.
Squashes, how grown, 327.
Stacking grain, when advisable, 219.
Stamens defined, 108.
Starch, manufacture of, 89.
Starchiness defined, 156.
Stems, climbing, 99.
erect, 99.
forms of, 98.
functions of, 98.
prostrate, 98.
Stigma defined, 108.
Stomata defined, 93.
Strawberries, how grown, 291.
pruning of, 303.
Structure of soil, crumb, 37.
how affected by freezing, 37.
how affected by humus, 38.
of soil, puddled, 37.
puddled, how caused, 37.
Style defined, 109.
Sulfur, 11.
Sunscald, injury by, 306.
Temperature of soil, how governed,
30.
optimum for germination, 30, 68.
INDEX
Tile drains, effect on air space, 29.
how water enters, 18.
why used, 18.
Tillage, effect on air space, 28.
why necessary, 36.
when soil is wet, 39.
Timothy, advantages of, 228.
time of cutting, 229.
use of, 227.
where grown, 227.
Tomatoes, how grown, 323.
Trampling soils when wet, 39.
Transpiration defined, 89.
Tree, how to tell age of, 102.
Tuber defined, 137.
Turnips, how grown, 322.
Vegetables, cool season, 311.
warm season, 312.
Vetches, methods of culture, 272.
range of, 249.
Vitality of seeds, how determined, 60.
Water, amount given off by leaves,
94.
film, or capillary, 19.
free, or gravity, 19.
Water-holding capacity,
fected by humus, 15.
Water-holding capacity of differ-
ent soils, 16.
Water, how lost from soil, 13.
hygroscopic, 19.
travels how from root to leaf, 101.
Watermelons, how grown, 327.
Weed seeds, weights of, 265.
Weeds, when most easily destroyed,
how af-
AD
Wheat, climatic conditions re-
quired, 205.
harvesting of, 211.
planting of, 210.
seed bed for, 207.
seed bed for, how prepared, 206.
seed, desirable characters of, 208.
selection of seed, 207.
spring, 205.
time of planting, 210.
uses of, 212.
why extensively grown, 203.
winter, or fall, 205.
Printed in the United States of America.
(ae ee
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King’s Irrigation and Drainage : ‘ ‘ A ; . : hese
Livingston’s Field Crop Production : ; ; Br ae? (6)
Lyon and Fippin’s The Principles of Soil Management 6 ‘ : Saar
Roberts’s The Fertility of the Land ,. ; 3 La5O
Snyder’s Soils and Fertilizers : m F : - : : : y nes
Voorhees’s Fertilizers. ‘ p : - A ; ¥ tie ix
Wheeler’s Manures and Fertilizers - ; C : : ; : ; Is00,
Widstoe’s Dry Farming . : : : - A : : : : Pde riste
ON GARDEN-MAKING
Bailey’s Garden-Making é ; : : - ; : ‘ ; Bi is(o
Bailey’s Vegetable Gardening : - 4 - ; : . : {Aso
French’s How to Grow Vegetables - : : : ‘ ‘ ap BETS
ON FRUIT GROWING, etc.
Bailey’s Fruit Growing. C A s . , . - 5 2 S75
Bailey’ s The Pruning Book . t : - - , - : Be eee
Card’s Bush Fruits . . - P : 5 F - : 5 : 7 1.50
ON THE CARE OF LIVE STOCK
Harper’s Animal Husbandry . A : “ ; 2 5 F : « 2ie4o
Jordan’s The Feeding of Animals . : ; 2 5 : - , SECO
Lyon’s How to Keep Bees for Profit . : : : : 5 3 of 852
Mayo’s Diseases of Animals . : : : : : : . - > B50
Phillips’s Beekeeping . ; ; ; : : : i) Es5O
Valentine’s How to Keep Hens for Profit . ‘ : - : : <) 1250
Watson’s Farm Poultry . : . - : Z : - 3 : 2 1250
ON DAIRY WORK
Kckles’s Dairy Cattle and Milk Production . , F ; , : ; (1560
Sheldon’s The Farm and the ery : : : - : : : . 1.00
Snyder’s Dairy Chemistry. : : : : : - : x $2200
Wing’s Milk and its Products : é : é ; ; : c eeks5o
ON PLANT DISEASES
Massee’s Diseases of Cultivated Plants and Trees ; : 2 ; - 2.25
O’Kane’s Injurious Insects. 5 z : . : : ; sa2I00
Slingerland and Crosby’s Fruit Insects . ; : é : : ; . 2,00
Stevens’s Fungi of Plant Disease . : : A : : < - - 400
ON ECONOMICS AND ORGANIZATION
Fairchild’s Rural Wealth and Welfare . ; ‘ ; . : . a2
Green’s Law for the American Farmer . : : : ; i 2 / .50
Ogden’s Rural Hygiene . : ; : < os (XA5O
Roberts’s The Farmer’s Business Handbook : ; A : ; - 1.25
THE MACMILLAN COMPANY
64-66 Fifth Avenue, New York
BOSTON CHICAGO ATLANTA DALLAS SAN FRANCISCO
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