Produced by Juliet Sutherland, Janet Blenkinship and the
Online Distributed Proofreading Team at http://www.pgdp.net.
This file is gratefully uploaded to the PG collection in
honor of Distributed Proofreaders having posted over
10,000 ebooks.
AGRICULTURE FOR
BEGINNERS
BY
CHARLES WILLIAM BURKETT
EDITOR OF THE _AMERICAN AGRICULTURIST_
FORMERLY DIRECTOR OF AGRICULTURAL EXPERIMENT STATION
KANSAS STATE AGRICULTURAL COLLEGE
FRANK LINCOLN STEVENS
PROFESSOR OF PLANT PATHOLOGY, UNIVERSITY OF ILLINOIS
FORMERLY TEACHER OF SCIENCE IN HIGH SCHOOL
COLUMBUS, OHIO
AND
DANIEL HARVEY HILL
FORMERLY PRESIDENT OF THE NORTH CAROLINA COLLEGE OF
AGRICULTURE AND MECHANIC ARTS
_REVISED EDITION_
GINN AND COMPANY
BOSTON . NEW YORK . CHICAGO . LONDON
ATLANTA . DALLAS . COLUMBUS . SAN FRANCISCO
COPYRIGHT, 1903, 1904, 1914, BY
CHARLES WILLIAM BURKETT, FRANK LINCOLN STEVENS AND DANIEL HARVEY HILL
ALL RIGHTS RESERVED
PRINTED IN THE UNITED STATES OF AMERICA
329.7
The Athenaeum Press
GINN AND COMPANY . PROPRIETORS . BOSTON . U.S.A.
[Illustration: GETTING READY FOR WINTER]
PREFACE
Since its first publication "Agriculture for Beginners" has found a
welcome in thousands of schools and homes. Naturally many suggestions as
to changes, additions, and other improvements have reached its authors.
Naturally, too, the authors have busied themselves in devising methods
to add to the effectiveness of the book. Some additions have been made
almost every year since the book was published. To embody all these
changes and helpful suggestions into a strictly unified volume; to add
some further topics and sections; to bring all farm practices up to the
ideals of to-day; to include the most recent teaching of scientific
investigators--these were the objects sought in the thorough revision
which has just been given the book. The authors hope and think that the
remaking of the book has added to its usefulness and attractiveness.
They believe now, as they believed before, that there is no line of
separation between the science of agriculture and the practical art of
agriculture. They are assured by the success of this book that
agriculture is eminently a teachable subject. They see no difference
between teaching the child the fundamental principles of farming and
teaching the same child the fundamental truths of arithmetic, geography,
or grammar. They hold that a youth should be trained for the farm just
as carefully as he is trained for any other occupation, and that it is
unreasonable to expect him to succeed without training.
If they are right in these views, the training must begin in the public
schools. This is true for two reasons:
1. It is universally admitted that aptitudes are developed, tastes
acquired, and life habits formed during the years that a child is in the
public school. Hence, during these important years every child intended
for the farm should be taught to know and love nature, should be led to
form habits of observation, and should be required to begin a study of
those great laws upon which agriculture is based. A training like this
goes far toward making his life-work profitable and delightful.
2. Most boys and girls reared on a farm get no educational training
except that given in the public schools. If, then, the truths that
unlock the doors of nature are not taught in the public schools, nature
and nature's laws will always be hid in night to a majority of our
bread-winners. They must still in ignorance and hopeless drudgery tear
their bread from a reluctant soil.
The authors return hearty thanks to Professor Thomas F. Hunt, University
of California; Professor Augustine D. Selby, Ohio Experiment Station;
Professor W. F. Massey, horticulturist and agricultural writer; and
Professor Franklin Sherman, Jr., State Entomologist of North Carolina,
for aid in proofreading and in the preparation of some of the material.
CONTENTS
CHAPTER I. THE SOIL
SECTION PAGE
I. ORIGIN OF THE SOIL 1
II. TILLAGE OF THE SOIL 6
III. THE MOISTURE OF THE SOIL 9
IV. HOW THE WATER RISES IN THE SOIL 13
V. DRAINING THE SOIL 14
VI. IMPROVING THE SOIL 17
VII. MANURING THE SOIL 21
CHAPTER II. THE SOIL AND THE PLANT
VIII. ROOTS 25
IX. HOW THE PLANT FEEDS FROM THE SOIL 29
X. ROOT-TUBERCLES 30
XI. THE ROTATION OF CROPS 33
CHAPTER III. THE PLANT
XII. HOW THE PLANT FEEDS FROM THE AIR 39
XIII. THE SAP CURRENT 40
XIV. THE FLOWER AND THE SEED 42
XV. POLLINATION 46
XVI. CROSSES, HYBRIDS, AND CROSS-POLLINATION 48
XVII. PROPAGATION BY BUDS 51
XVIII. PLANT SEEDING 59
XIX. SELECTING SEED CORN 66
XX. WEEDS 69
XXI. SEED PURITY AND VITALITY 72
CHAPTER IV. HOW TO RAISE A FRUIT TREE
XXII. GRAFTING 78
XXIII. BUDDING 81
XXIV. PLANTING AND PRUNING 83
CHAPTER V. HORTICULTURE
XXV. MARKET-GARDENING 89
XXVI. FLOWER-GARDENING 108
CHAPTER VI. THE DISEASES OF PLANTS
XXVII. THE CAUSE AND NATURE OF PLANT DISEASE 122
XXVIII. YEAST AND BACTERIA 127
XXIX. PREVENTION OF PLANT DISEASE 129
XXX. SOME SPECIAL PLANT DISEASES 130
CHAPTER VII. ORCHARD, GARDEN, AND FIELD INSECTS
XXXI. INSECTS IN GENERAL 144
XXXII. ORCHARD INSECTS 152
XXXIII. GARDEN AND FIELD INSECTS 165
XXXIV. THE COTTON-BOLL WEEVIL 173
CHAPTER VIII. FARM CROPS
XXXV. COTTON 180
XXXVI. TOBACCO 189
XXXVII. WHEAT 192
XXXVIII. CORN 197
XXXIX. PEANUTS 202
XL. SWEET POTATOES 204
XLI. WHITE, OR IRISH, POTATOES 206
XLII. OATS 209
XLIII. RYE 213
XLIV. BARLEY 215
XLV. SUGAR PLANTS 217
XLVI. HEMP AND FLAX 226
XLVII. BUCKWHEAT 229
XLVIII. RICE 231
XLIX. THE TIMBER CROP 232
L. THE FARM GARDEN 235
CHAPTER IX. FEED STUFFS
LI. GRASSES 238
LII. LEGUMES 244
CHAPTER X. DOMESTIC ANIMALS
LIII. HORSES 262
LIV. CATTLE 270
LV. SHEEP 276
LVI. SWINE 279
LVII. FARM POULTRY 282
LVIII. BEE CULTURE 286
LIX. WHY WE FEED ANIMALS 290
CHAPTER XI. FARM DAIRYING
LX. THE DAIRY COW 293
LXI. MILK, CREAM, CHURNING, AND BUTTER 297
LXII. HOW MILK SOURS 302
LXIII. THE BABCOCK MILK-TESTER 304
CHAPTER XII. MISCELLANEOUS
LXIV. GROWING FEED STUFFS ON THE FARM 309
LXV. FARM TOOLS AND MACHINES 313
LXVI. LIMING THE LAND 315
LXVII. BIRDS 318
LXVIII. FARMING ON DRY LAND 323
LXIX. IRRIGATION 326
LXX. LIFE IN THE COUNTRY 330
APPENDIX 339
GLOSSARY 342
INDEX 351
TO THE TEACHER
Teachers sometimes shrink from undertaking the teaching of a simple
textbook on agriculture because they are not familiar with all the
processes of farming. By the same reasoning they might hesitate to teach
arithmetic because they do not know calculus or to teach a primary
history of the United States because they are not versed in all history.
The art of farming is based on the sciences dealing with the growth of
plants and animals. This book presents in a simple way these fundamental
scientific truths and suggests some practices drawn from them. Hence,
even though many teachers may not have plowed or sowed or harvested,
such teachers need not be embarrassed in mastering and heartily
instructing a class in nature's primary laws.
If teachers realize how much the efficiency, comfort, and happiness of
their pupils will be increased throughout their lives from being taught
to cooeperate with nature and to take advantage of her wonderful laws,
they will eagerly begin this study. They will find also that their
pupils will be actively interested in these studies bearing on their
daily lives, and this interest will be carried over to other subjects.
Whenever you can, take the pupils into the field, the garden, the
orchard, and the dairy. Teach them to make experiments and to learn by
the use of their own eyes and brains. They will, if properly led,
astonish you by their efforts and growth.
You will find in the practical exercises many suggestions as to
experiments that you can make with your class or with individual
members. Do not neglect this first-hand teaching. It will be a delight
to your pupils. In many cases it will be best to finish the experiments
or observational work first, and later turn to the text to amplify the
pupil's knowledge.
Although the book is arranged in logical order, the teacher ought to
feel free to teach any topic in the season best suited to its study.
Omit any chapter or section that does not bear on your crops or does not
deal with conditions in your state.
The United States government and the different state experiment stations
publish hundreds of bulletins on agricultural subjects. These are sent
without cost, on application. It will be very helpful to get such of
these bulletins as bear on the different sections of the book. These
will be valuable additions to your school library. The authors would
like to give a list of these bulletins bearing on each chapter, but it
would soon be out of date, for the bulletins get out of print and are
supplanted by newer ones. However, the United States Department of
Agriculture prints a monthly list of its publications, and each state
experiment station keeps a list of its bulletins. A note to the
Secretary of Agriculture, Washington, D.C., or to your own state
experiment station will promptly bring you these lists, and from them
you can select what you need for your school.
AGRICULTURE FOR BEGINNERS
CHAPTER I
THE SOIL
SECTION I. ORIGIN OF THE SOIL
The word _soil_ occurs many times in this little book. In agriculture
this word is used to describe the thin layer of surface earth that, like
some great blanket, is tucked around the wrinkled and age-beaten form of
our globe. The harder and colder earth under this surface layer is
called the _subsoil_. It should be noted, however, that in waterless and
sun-dried regions there seems little difference between the soil and the
subsoil.
Plants, insects, birds, beasts, men,--all alike are fed on what grows in
this thin layer of soil. If some wild flood in sudden wrath could sweep
into the ocean this earth-wrapping soil, food would soon become as
scarce as it was in Samaria when mothers ate their sons. The face of the
earth as we now see it, daintily robed in grass, or uplifting waving
acres of corn, or even naked, water-scarred, and disfigured by man's
neglect, is very different from what it was in its earliest days. How
was it then? How was the soil formed?
Learned men think that at first the surface of the earth was solid rock.
How was this rock changed into workable soil? Occasionally a curious boy
picks up a rotten stone, squeezes it, and finds his hands filled with
dirt, or soil. Now, just as the boy crumbled with his fingers this
single stone, the great forces of nature with boundless patience
crumbled, or, as it is called, disintegrated, the early rock mass. The
simple but giant-strong agents that beat the rocks into powder with a
clublike force a millionfold more powerful than the club force of
Hercules were chiefly (1) heat and cold; (2) water, frost, and ice; (3)
a very low form of vegetable life; and (4) tiny animals--if such minute
bodies can be called animals. In some cases these forces acted singly;
in others, all acted together to rend and crumble the unbroken stretch
of rock. Let us glance at some of the methods used by these skilled
soil-makers.
Heat and cold are working partners. You already know that most hot
bodies shrink, or contract, on cooling. The early rocks were hot. As the
outside shell of rock cooled from exposure to air and moisture it
contracted. This shrinkage of the rigid rim of course broke many of the
rocks, and here and there left cracks, or fissures. In these fissures
water collected and froze. As freezing water expands with irresistible
power, the expansion still further broke the rocks to pieces. The
smaller pieces again, in the same way, were acted on by frost and ice
and again crumbled. This process is still a means of soil-formation.
Running water was another giant soil-former. If you would understand its
action, observe some usually sparkling stream just after a washing rain.
The clear waters are discolored by mud washed in from the surrounding
hills. As though disliking their muddy burden, the waters strive to
throw it off. Here, as low banks offer chance, they run out into
shallows and drop some of it. Here, as they pass a quiet pool, they
deposit more. At last they reach the still water at the mouth of the
stream, and there they leave behind the last of their mud load, and
often form of it little three-sided islands called _deltas_. In the same
way mighty rivers like the Amazon, the Mississippi, and the Hudson, when
they are swollen by rain, bear great quantities of soil in their sweep
to the seas. Some of the soil they scatter over the lowlands as they
whirl seaward; the rest they deposit in deltas at their mouths. It is
estimated that the Mississippi carries to the ocean each year enough
soil to cover a square mile of surface to a depth of two hundred and
sixty-eight feet.
[Illustration: FIG. 1. ROCK MARKED BY THE SCRAPING OF A GLACIER OVER IT]
The early brooks and rivers, instead of bearing mud, ran oceanward
either bearing ground stone that they themselves had worn from the rocks
by ceaseless fretting, or bearing stones that other forces had already
dislodged. The large pieces were whirled from side to side and beaten
against one another or against bedrock until they were ground into
smaller and smaller pieces. The rivers distributed this rock soil just
as the later rivers distribute muddy soil. For ages the moving waters
ground against the rocks. Vast were the waters; vast the number of
years; vast the results.
Glaciers were another soil-producing agent. Glaciers are streams "frozen
and moving slowly but irresistibly onwards, down well-defined valleys,
grinding and pulverizing the rock masses detached by the force and
weight of their attack." Where and how were these glaciers formed?
Once a great part of upper North America was a vast sheet of ice.
Whatever moisture fell from the sky fell as snow. No one knows what made
this long winter of snow, but we do know that snows piled on snows until
mountains of white were built up. The lower snow was by the pressure of
that above it packed into ice masses. By and by some change of climate
caused the masses of ice to break up somewhat and to move south and
west. These moving masses, carrying rock and frozen earth, ground them
to powder. King thus describes the stately movement of these snow
mountains: "Beneath the bottom of this slowly moving sheet of ice, which
with more or less difficulty kept itself conformable with the face of
the land over which it was riding, the sharper outstanding points were
cut away and the deeper river canons filled in. Desolate and rugged
rocky wastes were thrown down and spread over with rich soil."
The joint action of air, moisture, and frost was still another agent of
soil-making. This action is called _weathering_. Whenever you have
noticed the outside stones of a spring-house, you have noticed that tiny
bits are crumbling from the face of the stones, and adding little by
little to the soil. This is a slow way of making additions to the soil.
It is estimated that it would take 728,000 years to wear away limestone
rock to a depth of thirty-nine inches. But when you recall the
countless years through which the weather has striven against the rocks,
you can readily understand that its never-wearying activity has added
immensely to the soil.
In the rock soil formed in these various ways, and indeed on the rocks
themselves, tiny plants that live on food taken from the air began to
grow. They grew just as you now see mosses and lichens grow on the
surface of rocks. The decay of these plants added some fertility to the
newly formed soil. The life and death of each succeeding generation of
these lowly plants added to the soil matter accumulating on the rocks.
Slowly but unceasingly the soil increased in depth until higher
vegetable forms could flourish and add their dead bodies to it. This
vegetable addition to the soil is generally known as _humus_.
[Illustration: FIG. 2. GROUND ROCK AT END OF A GLACIER]
In due course of time low forms of animal life came to live on these
plants, and in turn by their work and their death to aid in making a
soil fit for the plowman.
Thus with a deliberation that fills man with awe, the powerful forces of
nature splintered the rocks, crumbled them, filled them with plant food,
and turned their flinty grains into a soft, snug home for vegetable
life.
SECTION II. TILLAGE OF THE SOIL
A good many years ago a man by the name of Jethro Tull lived in England.
He was a farmer and a most successful man in every way. He first taught
the English people and the world the value of thorough tillage of the
soil. Before and during his time farmers did not till the soil very
intelligently. They simply prepared the seed-bed in a careless manner,
as a great many farmers do to-day, and when the crops were gathered the
yields were not large.
Jethro Tull centered attention on the important fact that careful and
thorough tillage increases the available plant food in the soil. He did
not know why his crops were better when the ground was frequently and
thoroughly tilled, but he knew that such tillage did increase his yield.
He explained the fact by saying, "Tillage is manure." We have since
learned the reason for the truth that Tull taught, and, while his
explanation was incorrect, the practice that he was following was
excellent. The stirring of the soil enables the air to circulate through
it freely, and permits a breaking down of the compounds that contain the
elements necessary to plant growth.
You have seen how the air helps to crumble the stone and brick in old
buildings. It does the same with soil if permitted to circulate freely
through it. The agent of the air that chiefly performs this work is
called carbonic acid gas, and this gas is one of the greatest helpers
the farmer has in carrying on his work. We must not forget that in soil
preparation the air is just as important as any of the tools and
implements used in cultivation.
[Illustration: FIG. 3. SLOPE TO WATER SHOWS SOIL WEATHERED FROM FACE
OF CLIFF]
If the soil is fertile and if deep plowing has always been done, good
crops will result, other conditions being favorable. If, however, the
tillage is poor, scanty harvests will always result. For most soils a
two-horse plow is necessary to break up and pulverize the land.
A shallow soil can always be improved by properly deepening it. The
principle of greatest importance in soil-preparation is the gradual
deepening of the soil in order that plant-roots may have more
comfortable homes. If the farmer has been accustomed to plow but four
inches deep, he should adjust the plow so as to turn five inches at the
next plowing, then six, and so on until the seed-bed is nine or ten
inches deep. This gradual deepening will not injure the soil but will
put it quickly in good condition. If to good tillage rotation of crops
be added, the soil will become more fertile with each succeeding year.
[Illustration: FIG. 4. MIXED GRASSES GROWN FOR FORAGE]
The plow, harrow, and roller are all necessary to good tillage and to a
proper preparation of the seed-bed. The soil must be made compact and
clods of all sizes must be crushed. Then the air circulates freely, and
paying crops are the rule and not the exception.
Tillage does these things: it increases the plant-food supply, destroys
weeds, and influences the moisture content of the soil.
=EXERCISE=
1. What tools are used in tillage?
2. How should a poor and shallow soil be treated?
3. Why should a poor and shallow soil be well compacted before
sowing the crop?
4. Explain the value of a circulation of air in the soil.
5. What causes iron to rust?
6. Why is a two-horse turning-plow better than a one-horse plow?
7. Where will clods do the least harm--on top of the soil or below
the surface?
8. Do plant roots penetrate clods?
9. Are earthworms a benefit or an injury to the soil?
10. Name three things that tillage does.
SECTION III. THE MOISTURE OF THE SOIL
Did any one ever explain to you how important water is to the soil, or
tell you why it is so important? Often, as you know, crops entirely fail
because there is not enough water in the soil for the plants to drink.
How necessary is it, then, that the soil be kept in the best possible
condition to catch and hold enough water to carry the plant through dry,
hot spells! Perhaps you are ready to ask, "How does the mouthless plant
drink its stored-up water?"
The plant gets all its water through its roots. You have seen the tiny
threadlike roots of a plant spreading all about in fine soil; they are
down in the ground taking up plant food and water for the stalk and
leaves above. The water, carrying plant food with it, rises in a simple
but peculiar way through the roots and stems.
The plants use the food for building new tissue, that is, for growth.
The water passes out through the leaves into the air. When the summers
are dry and hot and there is but little water in the soil, the leaves
shrink up. This is simply a method they have of keeping the water from
passing too rapidly off into the air. I am sure you have seen the corn
blades all shriveled on very hot days. This shrinkage is nature's way of
diminishing the current of water that is steadily passing through the
plant.
A thrifty farmer will try to keep his soil in such good condition that
it will have a supply of water in it for growing crops when dry and hot
weather comes. He can do this by deep plowing, by subsoiling, by adding
any kind of decaying vegetable matter to the soil, and by growing crops
that can be tilled frequently.
The soil is a great storehouse for moisture. After the clouds have
emptied their waters into this storehouse, the water of the soil comes
to the surface, where it is evaporated into the air. The water comes to
the surface in just the same way that oil rises in a lamp-wick. This
rising of the water is called _capillarity_.
[Illustration: FIG. 5. AN ENLARGED VIEW OF A SECTION OF MOIST SOIL,
SHOWING AIR SPACES AND SOIL PARTICLES]
It is necessary to understand what is meant by this big word. If into a
pan of water you dip a glass tube, the water inside the tube rises above
the level of the water in the pan. The smaller the tube the higher will
the water rise. The greater rise inside is perhaps due to the fact that
the glass attracts the particles of water more than the particles of
water attract one another. Now apply this principle to the soil.
[Illustration: FIG. 6. THE RIGHT WAY TO PLOW]
The soil particles have small spaces between them, and the spaces act
just as the tube does. When the water at the surface is carried away by
drying winds and warmth, the water deeper in the soil rises through
the soil spaces. In this way water is brought from its soil storehouse
as plants need it.
[Illustration: FIG. 7. APPARATUS FOR TESTING THE HOLDING OF WATER BY
DIFFERENT SOILS]
Of course when the underground water reaches the surface it evaporates.
If we want to keep it for our crops, we must prepare a trap to hold it.
Nature has shown us how this can be done. Pick up a plank as it lies on
the ground. Under the plank the soil is wet, while the soil not covered
by the plank is dry. Why? Capillarity brought the water to the surface,
and the plank, by keeping away wind and warmth, acted as a trap to hold
the moisture. Now of course a farmer cannot set a trap of planks over
his fields, but he can make a trap of dry earth, and that will do just
as well.
When a crop like corn or cotton or potatoes is cultivated, the fine,
loose dirt stirred by the cultivating-plow will make a mulch that serves
to keep water in the soil in the same way that the plank kept moisture
under it. The mulch also helps to absorb the rains and prevents the
water from running off the surface. Frequent cultivation, then, is one
of the best possible ways of saving moisture. Hence the farmer who most
frequently stirs his soil in the growing season, and especially in
seasons of drought, reaps, other things being equal, a more abundant
harvest than if tillage were neglected.
=EXERCISE=
1. Why is the soil wet under a board or under straw?
2. Will a soil that is fine and compact produce better crops than
one that is loose and cloddy? Why?
3. Since the water which a plant uses comes through the roots, can
the morning dew afford any assistance?
4. Why are weeds objectionable in a growing crop?
5. Why does the farmer cultivate growing corn and cotton?
SECTION IV. HOW THE WATER RISES IN THE SOIL
[Illustration: FIG. 8. USING LAMP-CHIMNEYS TO SHOW THE RISE OF WATER
IN SOIL]
When the hot, dry days of summer come, the soil depends upon the
subsoil, or undersoil, for the moisture that it must furnish its growing
plants. The water was stored in the soil during the fall, winter, and
spring months when there was plenty of rain. If you dig down into the
soil when everything is dry and hot, you will soon reach a cool, moist
undersoil. The moisture increases as you dig deeper into the soil.
Now the roots of plants go down into the soil for this moisture, because
they need the water to carry the plant food up into the stems and
leaves.
You can see how the water rises in the soil by performing a simple
experiment.
=EXPERIMENT=
Take a lamp-chimney and fill it with fine, dry dirt. The dirt from
a road or a field will do. Tie over the smaller end of the
lamp-chimney a piece of cloth or a pocket handkerchief, and place
this end in a shallow pan of water. If the soil in the lamp-chimney
is clay and well packed, the water will quickly rise to the top.
By filling three or four lamp-chimneys with as many different
soils, the pupil will see that the water rises more slowly in some
than in others.
Now take the water pan away, and the water in the lamp-chimneys
will gradually evaporate. Study for a few days the effect of
evaporation on the several soils.
SECTION V. DRAINING THE SOIL
A wise man was once asked, "What is the most valuable improvement ever
made in agriculture?" He answered, "Drainage." Often soils unfit for
crop-production because they contain too much water are by drainage
rendered the most valuable of farming lands.
Drainage benefits land in the following ways:
1. It deepens the subsoil by removing unnecessary water from the spaces
between the soil particles. This admits air. Then the oxygen which is in
the air, by aiding decay, prepares plant food for vegetation.
2. It makes the surface soil, or topsoil, deeper. It stands to reason
that the deeper the soil the more plant food becomes available for plant
use.
3. It improves the texture of the soil. Wet soil is sticky. Drainage
makes this sticky soil crumble and fall apart.
4. It prevents washing.
5. It increases the porosity of soils and permits roots to go deeper
into the soil for food and moisture.
6. It increases the warmth of the soil.
7. It permits earlier working in spring and after rains.
[Illustration: FIG. 9. LAYING A TILE DRAIN]
8. It favors the growth of germs which change the unavailable nitrogen
of the soil into nitrates; that is, into the form of nitrogen most
useful to plants.
9. It enables plants to resist drought better because the roots go into
the ground deeper early in the season.
A soil that is hard and wet will not grow good crops. The
nitrogen-gathering crops will store the greatest quantity of nitrogen in
the soil when the soil is open to the free circulation of the air.
These valuable crops cannot do this when the soil is wet and cold.
Sandy soils with sandy subsoils do not often need drainage; such soils
are naturally drained. With clay soils it is different. It is very
important to remove the stagnant water in them and to let the air in.
When land has been properly drained the other steps in improvement are
easily taken. After soil has been dried and mellowed by proper drainage,
then commercial fertilizers, barnyard manure, cowpeas, and clover can
most readily do their great work of improving the texture of the soil
and of making it fitter for plant growth.
[Illustration: FIG. 10. A TILE IN POSITION]
=Tile Drains.= Tile drains are the best and cheapest that can be used.
It would not be too strong to say that draining by tiles is the most
perfect drainage. Thousands of practical tests in this country have
proved the superiority of tile draining for the following reasons:
1. Good tile drains properly laid last for years and do not fill up.
2. They furnish the cheapest possible means of removing too much water
from the soil.
3. They are out of reach of all cultivating tools.
4. Surface water in filtering through the tiles leaves its nutritious
elements for plant growth.
=EXPERIMENTS=
=To show the Effect of Drainage.= Take two tomato cans and fill
both with the same kind of soil. Punch several holes in the bottom
of one to drain the soil above and to admit air circulation. Leave
the other unpunctured. Plant seeds of any kind in both cans and
keep in a warm place. Add every third day equal quantities of
water. Let seeds grow in both cans and observe the difference in
growth for two or three weeks.
=To show the Effect of Air in Soils.= Take two tomato cans; fill
one with soil that is loose and warm, and the other with wet clay
or muck from a swampy field. Plant a few seeds of the same kind in
each and observe how much better the dry, warm, open soil is for
growing farm crops.
SECTION VI. IMPROVING THE SOIL
We hear a great deal about the exhaustion or wearing out of the soil.
Many uncomfortable people are always declaring that our lands will no
longer produce profitable crops, and hence that farming will no longer
pay.
Now it is true, unfortunately, that much land has been robbed of its
fertility, and, because this is true, we should be most deeply
interested in everything that leads to the improvement of our soils.
When our country was first discovered and trees were growing everywhere,
we had virgin soils, or new soils that were rich and productive because
they were filled with vegetable matter and plant food. There are not
many virgin soils now because the trees have been cut from the best
lands, and these lands have been farmed so carelessly that the vegetable
matter and available plant food have been largely used up. Now that
fresh land is scarce it is very necessary to restore fertility to these
exhausted lands. What are some of the ways in which this can be done?
[Illustration: FIG. 11. CLOVER IS A SOIL-IMPROVER]
There are several things to be done in trying to reclaim worn-out land.
One of the first of these is to till the land well. Many of you may have
heard the story of the dying father who called his sons about him and
whispered feebly, "There is great treasure hidden in the garden." The
sons could hardly wait to bury their dead father before, thud, thud,
thud, their picks were going in the garden. Day after day they dug; they
dug deep; they dug wide. Not a foot of the crop-worn garden escaped the
probing of the pick as the sons feverishly searched for the expected
treasure. But no treasure was found. Their work seemed entirely useless.
[Illustration: FIG. 12. INCREASING THE PRODUCTIVE POWER OF THE SOIL
Second crop of cowpeas on old, abandoned land]
"Let us not lose every whit of our labor; let us plant this pick-scarred
garden," said the eldest. So the garden was planted. In the fall the
hitherto neglected garden yielded a harvest so bountiful, so unexpected,
that the meaning of their father's words dawned upon them. "Truly," they
said, "a treasure was hidden there. Let us seek it in all our fields."
The story applies as well to-day as it did when it was first told.
Thorough culture of the soil, frequent and intelligent tillage--these
are the foundations of soil-restoration.
Along with good tillage must go crop-rotation and good drainage. A
supply of organic matter will prevent heavy rains from washing the soil
and carrying away plant food. Drainage will aid good tillage in allowing
air to circulate between the soil particles and in arranging plant food
so that plants can use it.
But we must add humus, or vegetable matter, to the soil. You remember
that the virgin soils contained a great deal of vegetable matter and
plant food, but by the continuous growing of crops like wheat, corn, and
cotton, and by constant shallow tillage, both humus and plant food have
been used up. Consequently much of our cultivated soil to-day is hard
and dead.
There are three ways of adding humus and plant food to this lifeless
land: the first way is to apply barnyard manure (to adopt this method
means that livestock raising must be a part of all farming); the second
way is to adopt rotation of crops, and frequently to plow under crops
like clover and cowpeas; the third way is to apply commercial
fertilizers.
To summarize: if we want to make our soil better year by year, we must
cultivate well, drain well, and in the most economical way add humus and
plant food.
=EXPERIMENT=
Select a small area of ground at your home and divide it into four
sections, as shown in the following sketch:
On Section _A_ apply barnyard manure; on Section _B_ apply
commercial fertilizers; on Section _C_ apply nothing, but till
well; on Section _D_ apply nothing, and till very poorly.
_A_, _B_, and _C_ should all be thoroughly plowed and harrowed.
Then add barnyard manure to _A_, commercial fertilizers to _B_, and
harrow _A_, _B_, and _C_ at least four times until the soil is
mellow and fine. _D_ will most likely be cloddy, like many fields
that we often see. Now plant on each plat some crop like cotton,
corn, or wheat. When the plats are ready to harvest, measure the
yield of each and determine whether the increased yield of the best
plats has paid for the outlay for tillage and manure. The pupil
will be much interested in the results obtained from the first
crop.
[Illustration: FIG. 13]
Now follow a system of crop-rotation on the plats. Clover can
follow corn or cotton or wheat; and cowpeas, wheat. Then determine
the yield of each plat for the second crop. By following these
plats for several years, and increasing the number, the pupils will
learn many things of greatest value.
SECTION VII. MANURING THE SOIL
In the early days of our history, when the soil was new and rich, we
were not compelled to use large amounts of manures and fertilizers. Yet
our histories speak of an Indian named Squanto who came into one of the
New England colonies and showed the first settlers how, by putting a
fish in each hill of corn, they could obtain larger yields.
If people in those days, with new and fertile soils, could use manures
profitably, how much more ought we to use them in our time, when soils
have lost their virgin fertility, and when the plant food in the soil
has been exhausted by years and years of cropping!
To sell year after year all the produce grown on land is a sure way to
ruin it. If, for example, the richest land is planted every year in
corn, and no stable or farmyard manure or other fertilizer returned to
the soil, the land so treated will of course soon become too poor to
grow any crop. If, on the other hand, clover or alfalfa or corn or
cotton-seed meal is fed to stock, and the manure from the stock returned
to the soil, the land will be kept rich. Hence those farmers who do not
sell such raw products as cotton, corn, wheat, oats, and clover, but who
market articles made from these raw products, find it easier to keep
their land fertile. For illustration: if instead of selling hay, farmers
feed it to sheep and sell meat and wool; if instead of selling cotton
seed, they feed its meal to cows, and sell milk and butter; if instead
of selling stover, they feed it to beef cattle, they get a good price
for products and in addition have all the manure needed to keep their
land productive and increase its value each year.
[Illustration:FIG. 14. RELATION OF HUMUS TO GROWTH OF CORN
1, clay subsoil; 2, same, with fertilizer; 3, same, with humus]
If we wish to keep up the fertility of our lands we should not allow
anything to be lost from our farms. All the manures, straw, roots,
stubble, healthy vines--in fact everything decomposable--should be
plowed under or used as a top-dressing. Especial care should be taken in
storing manure. It should be watchfully protected from sun and rain. If
a farmer has no shed under which to keep his manure, he should scatter
it on his fields as fast as it is made.
[Illustration: FIG. 15. THE COTTON PLANT WITH AND WITHOUT FOOD
In left top pot, no plant food; in left bottom pot, plant food scanty;
in both right pots, all elements of plant food present]
He should understand also that liquid manure is of more value than
solid, because that important plant food, nitrogen, is found almost
wholly in the liquid portion. Some of the phosphoric acid and
considerable amounts of the potash are also found in the liquid manure.
Hence economy requires that none of this escape either by leakage or by
fermentation. Sometimes one can detect the smell of ammonia in the
stable. This ammonia is formed by the decomposition of the liquid
manure, and its loss should be checked by sprinkling some floats, acid
phosphate, or muck over the stable floor.
Many farmers find it desirable to buy fertilizers to use with the manure
made on the farm. In this case it is helpful to understand the
composition, source, and availability of the various substances
composing commercial fertilizers. The three most valuable things in
commercial fertilizers are nitrogen, potash, and phosphoric acid.
The nitrogen is obtained from (1) nitrate of soda mined in Chile, (2)
ammonium sulphate, a by-product of the gas works, (3) dried blood and
other by-products of the slaughter-houses, and (4) cotton-seed meal.
Nitrate of soda is soluble in water and may therefore be washed away
before being used by plants. For this reason it should be applied in
small quantities and at intervals of a few weeks.
Potash is obtained in Germany, where it is found in several forms. It is
put on the market as muriate of potash, sulphate of potash, kainite,
which contains salt as an impurity, and in other impure forms. Potash is
found also in _unleached_ wood ashes.
Phosphoric acid is found in various rocks of Tennessee, Florida, and
South Carolina, and also to a large extent in bones. The rocks or bones
are usually treated with sulphuric acid. This treatment changes the
phosphoric acid into a form ready for plant use.
These three kinds of plant food are ordinarily all that we need to
supply. In some cases, however, lime has to be added. Besides being a
plant food itself, lime helps most soils by improving the structure of
the grains; by sweetening the soil, thereby aiding the little living
germs called _bacteria_; by hastening the decay of organic matter; and
by setting free the potash that is locked up in the soil.
CHAPTER II
THE SOIL AND THE PLANT
SECTION VIII. ROOTS
[Illustration: FIG. 16. ROOT-HAIRS ON A RADISH]
You have perhaps observed the regularity of arrangement in the twigs and
branches of trees. Now pull up the roots of a plant, as, for example,
sheep sorrel, Jimson weed, or some other plant. Note the branching of
the roots. In these there is no such regularity as is seen in the twig.
Trace the rootlets to their finest tips. How small, slender, and
delicate they are! Still we do not see the finest of them, for in taking
the plant from the ground we tore the most delicate away. In order to
see the real construction of a root we must grow one so that we may
examine it uninjured. To do this, sprout some oats in a germinator or in
any box in which one glass side has been arranged and allow the oats to
grow till they are two or more inches high. Now examine the roots and
you will see very fine hairs, similar to those shown in the accompanying
figure, forming a fuzz over the surface of the roots near the tips. This
fuzz is made of small hairs standing so close together that there are
often as many as 38,200 on a single square inch. Fig. 17 shows how a
root looks when it has been cut crosswise into what is known as a cross
section. The figure is much increased in size. You can see how the
root-hairs extend from the root in every direction. Fig. 18 shows a
single root-hair very greatly enlarged, with particles of sand sticking
to it.
[Illustration: FIG. 17. A SLICE OF A ROOT
Highly magnified]
These hairs are the feeding-organs of the roots, and they are formed
only near the tips of the finest roots. You see that the large, coarse
roots that you are familiar with have nothing to do with _absorbing_
plant food from the soil. They serve merely to _conduct_ the sap and
nourishment from the root-hairs to the tree.
When you apply manure or other fertilizer to a tree, remember that it is
far better to supply the fertilizer to the roots that are at some
distance from the trunk, for such roots are the real feeders. The plant
food in the manure soaks into the soil and immediately reaches the
root-hairs. You can understand this better by studying the distribution
of the roots of an orchard tree, shown in Fig. 19. There you can see
that the fine tips are found at a long distance from the main trunk.
[Illustration: FIG. 18. A ROOT-HAIR WITH PARTICLES OF SOIL STICKING
TO IT]
You can now readily see why it is that plants usually wilt when they are
transplanted. The fine, delicate root-hairs are then broken off, and the
plant can but poorly keep up its food and water supply until new hairs
have been formed. While these are forming, water has been evaporating
from the leaves, and consequently the plant does not get enough moisture
and therefore droops.
[Illustration: FIG. 19. DISTRIBUTION OF APPLE-TREE ROOTS]
Would you not conclude that it is very poor farming to till deeply any
crop after the roots have extended between the rows far enough to be cut
by the plow or cultivator? In cultivating between corn rows, for
example, if you find that you are disturbing fine roots, you may be sure
that you are breaking off millions of root-hairs from each plant and
hence are doing harm rather than good. Fig. 20 shows how the roots from
one corn row intertangle with those of another. You see at a glance how
many of these roots would be destroyed by deep cultivation. Stirring
the upper inch of soil when the plants are well grown is sufficient
tillage and does no injury to the roots.
[Illustration: FIG. 20. CORN ROOTS REACH FROM ROW TO ROW]
A deep soil is much better than a shallow soil, as its depth makes it
just so much easier for the roots to seek deep food. Fig. 21 illustrates
well how far down into the soil the alfalfa roots go.
[Illustration: FIG. 21 ALFALFA ROOT]
=EXERCISE=
Dig up the roots of several cultivated plants and weeds and compare
them. Do you find some that are fine or fibrous? some fleshy like
the carrot? The dandelion is a good example of a tap-root.
Tap-roots are deep feeders. Examine very carefully the roots of a
medium-sized corn plant. Sift the dirt away gently so as to loosen
as few roots as possible. How do the roots compare in area with the
part above the ground? Try to trace a single root of the corn plant
from the stalk to its very tip. How long are the roots of mature
plants? Are they deep or shallow feeders? Germinate some oats or
beans in a glass-sided box, as suggested, and observe the
root-hairs.
SECTION IX. HOW THE PLANT FEEDS FROM THE SOIL
Plants receive their nourishment from two sources--from the air and from
the soil. The soil food, or mineral food, dissolved in water, must reach
the plant through the root-hairs with which all plants are provided in
great numbers. Each of these hairs may be compared to a finger reaching
among the particles of earth for food and water. If we examine the
root-hairs ever so closely, we find no holes, or openings, in them. It
is evident, then, that no solid particles can enter the root-hairs, but
that all food must pass into the root in solution.
An experiment just here will help us to understand how a root feeds.
[Illustration: FIG. 22. EXPERIMENT TO SHOW HOW ROOTS TAKE UP FOOD]
=EXPERIMENT=
Secure a narrow glass tube like the one in Fig. 22. If you cannot
get a tube, a narrow, straight lamp-chimney will, with a little
care, do nearly as well. From a bladder made soft by soaking, cut a
piece large enough to cover the end of the tube or chimney and to
hang over a little all around. Make the piece of bladder secure to
the end of the tube by wrapping tightly with a waxed thread, as at
B. Partly fill the tube with molasses (or it may be easier in case
you use a narrow tube to fill it before attaching the bladder). Put
the tube into a jar or bottle of water so placed that the level of
the molasses inside and the water outside will be the same. Fasten
the tube in this position and observe it frequently for three or
four hours. At the end of the time you should find that the
molasses in the tube has risen above the level of the liquid
outside. It may even overflow at the top. If you use the
lamp-chimney the rise will not be so clearly seen, since a greater
volume is required to fill the space in the chimney. This increase
in the contents of the tube is due to the entrance of water from
the outside. The water has passed through the thin bladder, or
membrane, and has come to occupy space in the tube. There is also a
passage the other way, but the molasses can pass through the
bladder membrane so slowly that the passage is scarcely noticeable.
There are no holes, or openings, in the membrane, but still there
is a free passage of liquids in both directions, although the more
heavily laden solution must move more slowly.
A root-hair acts in much the same way as the tube in our experiment,
with the exception that it is so made as to allow certain substances to
pass in only one direction, that is, toward the inside. The outside of
the root-hair is bathed in solutions rich in nourishment. The
nourishment passes from the outside to the inside through the delicate
membrane of the root-hair. Thus does food enter the plant-root. From the
root-hairs, foods are carried to the inside of the root.
From this you can see how important it is for a plant to have fine,
loose soil for its root-hairs; also how necessary is the water in the
soil, since the food can be used only when it is dissolved in water.
This passage of liquids from one side of a membrane to another is called
_osmosis_. It has many uses in the plant kingdom. We say a root takes
nourishment by osmosis.
SECTION X. ROOT-TUBERCLES
Tubercle is a big word, but you ought to know how to pronounce it and
what is meant by root-tubercles. We are going to tell you what a
root-tubercle is and something about its importance to agriculture. When
you have learned this, we are sure you will want to examine some plants
for yourself in order that you may see just what tubercles look like on
a real root.
Root-tubercles do not form on all kinds of plants that farmers grow.
They are formed only on those kinds that botanists call _legumes_. The
clovers, cowpeas, vetches, soy beans, and alfalfa are all legumes. The
tubercles are little knotty, wart-like growths on the roots of the
plants just named. These tubercles are caused by tiny forms of life
called, as you perhaps already know, bacteria, or _germs_.
[Illustration: FIG. 23. TUBERCLES ON CLOVER ROOTS
The specimen at the right was grown in soil inoculated with soil from an
old clover field. The one at the left was grown in soil not inoculated]
Instead of living in nests in trees like birds or in the ground like
moles and worms, these tiny germs, less than one twenty-five thousandth
of an inch long, make their homes on the roots of legumes. Nestling
snugly together, they live, grow, and multiply in their sunless homes.
Through their activity the soil is enriched by the addition of much
nitrogen from the air. They are the good fairies of the farmer, and no
magician's wand ever blessed a land so much as these invisible folk
bless the land that they live in.
Just as bees gather honey from the flowers and carry it to the hives,
where they prepare it for their own future use and for the use of
others, so do these root-tubercles gather nitrogen from the air and fix
it in their root homes, where it can be used by other crops.
[Illustration: FIG. 24. SOY BEANS AND COWPEAS, TWO GREAT SOIL-IMPROVERS]
In the earlier pages of this book you were told something about the food
of plants. One of the main elements of plant food, perhaps you remember,
is nitrogen. Just as soon as the roots of the leguminous plants begin to
push down into the soil, the bacteria, or germs that make the tubercles,
begin to build their homes on the roots, and in so doing they add
nitrogen to the soil. You now see the importance of growing such crops
as peas and clover on your land, for by their tubercles you can
constantly add plant food to the soil. Now this much-needed nitrogen is
the most costly part of the fertilizers that farmers buy every year. If
every farmer, then, would grow these tubercle-bearing crops, he would
rapidly add to the richness of his land and at the same time escape the
necessity of buying so much expensive fertilizer.
=EXPERIMENT=
Take a spade or shovel and dig carefully around the roots of a
cowpea and a clover plant; loosen the earth thoroughly and then
pull the plants up, being careful not to break off any of the
roots. Now wash the roots, and after they become dry count the
nodules, or tubercles, on them. Observe the difference in size. How
are they arranged? Do all leguminous plants have equal numbers of
nodules? How do these nodules help the farmer?
SECTION XI. THE ROTATION OF CROPS
Doubtless you know what is meant by rotation, for your teacher has
explained to you already how the earth rotates, or turns, on its axis
and revolves around the sun. When we speak of crop-rotation we mean not
only that the same crop should not be planted on the same land for two
successive years but that crops should follow one another in a regular
order.
Many farmers do not follow a system of farming that involves a change of
crops. In some parts of the country the same fields are planted to corn
or wheat or cotton year after year. This is not a good practice and
sooner or later will wear out the soil completely, because the
soil-elements that furnish the food of that constant crop are soon
exhausted and good crop-production is no longer possible.
Why is crop-rotation so necessary? There are different kinds of plant
food in the soil. If any one of these is used up, the soil of course
loses its power to feed plants properly. Now each crop uses more of some
of the different kinds of foods than others do, just as you like some
kinds of food better than others. But the crop cannot, as you can, learn
to use the kinds of food it does not like; it must use the kind that
nature fitted it to use. Not only do different crops feed upon different
soil foods, but they use different quantities of these foods.
Now if a farmer plant the same crop in the same field each year, that
crop soon uses up all of the available plant food that it likes. Hence
the soil can no longer properly nourish the crop that has been year by
year robbing it. If that crop is to be successfully grown again on the
land, the exhausted element must be restored.
[Illustration: FIG. 25. GRASS FOLLOWING CORN]
This can be done in two ways: first, by finding out what element has
here been exhausted, and then restoring this element by means either of
commercial fertilizers or manure; second, by planting on the land crops
that feed on different food and that will allow or assist kind Mother
Nature "to repair her waste places." An illustration may help you to
remember this fact. Nitrogen is, as already explained, one of the
commonest plant foods. It may almost be called plant bread. The wheat
crop uses up a good deal of nitrogen. Suppose a field were planted in
wheat year after year. Most of the available nitrogen would be taken out
of the soil after a while, and a new wheat crop, if planted on the
field, would not get enough of its proper food to yield a paying
harvest. This same land, however, that could not grow wheat could
produce other crops that do not require so much nitrogen. For example,
it could grow cowpeas. Cowpeas, aided by their root-tubercles, are able
to gather from the air a great part of the nitrogen needed for their
growth. Thus a good crop of peas can be obtained even if there is little
available nitrogen in the soil. On the other hand wheat and corn and
cotton cannot use the free nitrogen of the air, and they suffer if there
is an insufficient quantity present in the soil; hence the necessity of
growing legumes to supply what is lacking.
[Illustration: FIG. 26. COWPEAS AND CORN--AUGUST]
Let us now see how easily plant food may be saved by the rotation of
crops.
If you sow wheat in the autumn it is ready to be harvested in time for
planting cowpeas. Plow or disk the wheat stubble, and sow the same field
to cowpeas. If the wheat crop has exhausted the greater part of the
nitrogen of the soil, it makes no difference to the cowpea; for the
cowpea will get its nitrogen from the air and not only provide for its
own growth but will leave quantities of nitrogen in the queer nodules of
its roots for the crops coming after it in the rotation.
[Illustration: FIG. 27. COWPEAS AND CORN--OCTOBER]
If corn be planted, there should be a rotation in just the same way. The
corn plant, a summer grower, of course uses a certain portion of the
plant food stored in the soil. In order that the crop following the corn
may feed on what the corn did not use, this crop should be one that
requires a somewhat different food. Moreover, it should be one that fits
in well with corn so as to make a winter crop. We find just such a
plant in clover or wheat. Like the cowpea, all the varieties of clover
have on their roots tubercles that add the important element, nitrogen,
to the soil.
From these facts is it not clear that if you wish to improve your land
quickly and keep it always fruitful you must practice crop-rotation?
AN ILLUSTRATION OF CROP-ROTATION
Here are two systems of crop-rotation as practiced at one or more
agricultural experiment stations. Each furnishes an ideal plan for
keeping up land.
---------------------++----------------------++----------------------
---------------------++----------------------++----------------------
FIRST YEAR || SECOND YEAR || THIRD YEAR
----------+----------++-----------+----------++-----------+----------
Summer | Winter || Summer | Winter || Summer | Winter
----------+----------++-----------+----------++-----------+----------
Corn | Crimson || Cotton | Wheat || Cowpeas | Rye for
| clover || | || | pasture
----------+----------++-----------+----------++-----------+----------
or
----------+----------++-----------+----------++-----------+----------
Summer | Winter || Summer | Winter || Summer | Winter
----------+----------++-----------+----------++-----------+----------
Corn | Wheat || Clover | Clover || Grass | Grass for
| || and grass | and grass|| |pasture or
| || | || | meadow
----------+----------++-----------+----------++-----------+----------
----------+----------++-----------+----------++-----------+----------
In these rotations the cowpeas and clovers are nitrogen-gathering crops.
They not only furnish hay but they enrich the soil. The wheat, corn, and
cotton are money crops, but in addition they are cultivated crops; hence
they improve the physical condition of the soil and give opportunity to
kill weeds. The grasses and clovers are of course used for pasturage and
hay. This is only a suggested rotation. Work out one that will meet your
home need.
=EXERCISE=
Let the pupils each present a system of rotation that includes the
crops raised at home. The system presented should as nearly as
possible meet the following requirements:
1. Legumes for gathering nitrogen.
2. Money crops for cash income.
3. Cultivated crops for tillage and weed-destruction.
4. Food crops for feeding live stock.
CHAPTER III
THE PLANT
SECTION XII. HOW A PLANT FEEDS FROM THE AIR
If you partly burn a match you will see that it becomes black. This
black substance into which the match changes is called _carbon_. Examine
a fresh stick of charcoal, which is, as you no doubt know, burnt wood.
You see in the charcoal every fiber that you saw in the wood itself.
This means that every part of the plant contains carbon. How important,
then, is this substance to the plant!
You will be surprised to know that the total amount of carbon in plants
comes from the air. All the carbon that a plant gets is taken in by the
leaves of the plant; not a particle is gathered by the roots. A large
tree, weighing perhaps 11,000 pounds, requires in its growth carbon from
16,000,000 cubic yards of air.
Perhaps, after these statements, you may think there is danger that the
carbon of the air may sometime become exhausted. The air of the whole
world contains about 1,760,000,000,000 pounds of carbon. Moreover, this
is continually being added to by our fires and by the breath of animals.
When wood or coal is used for fuel the carbon of the burning substance
is returned to the air in the form of gas. Some large factories burn
great quantities of coal and thus turn much carbon back to the air. A
single factory in Germany is estimated to give back to the air daily
about 5,280,000 pounds of carbon. You see, then, that carbon is
constantly being put back into the air to replace that which is used by
growing plants.
The carbon of the air can be used by none but green plants, and by them
only in the sunlight. We may compare the green coloring matter of the
leaf to a machine, and the sunlight to the power, or energy, which keeps
the machine in motion. By means, then, of sunlight and the green
coloring matter of the leaves, the plant secures carbon. The carbon
passes into the plant and is there made into two foods very necessary to
the plant; namely, starch and sugar.
Sometimes the plant uses the starch and sugar immediately. At other
times it stores both away, as it does in the Irish and the sweet potato
and in beets, cabbage, peas, and beans. These plants are used as food by
man because they contain so much nourishment; that is, starch and sugar
which were stored away by the plant for its own future use.
=EXERCISE=
Examine some charcoal. Can you see the rings of growth? Slightly
char paper, cloth, meat, sugar, starch, etc. What does the turning
black prove? What per cent of these substances do you think is pure
carbon?
SECTION XIII. THE SAP CURRENT
The root-hairs take nourishment from the soil. The leaves manufacture
starch and sugar. These manufactured foods must be carried to all parts
of the plant. There are two currents to carry them. One passes from the
roots through the young wood to the leaves, and one, a downward current,
passes through the bark, carrying needed food to the roots (see Fig.
28).
If you should injure the roots, the water supply to the leaves would be
cut off and the leaves would immediately wither. On the other hand, if
you remove the bark, that is, girdle the tree, you in no way interfere
with the water supply and the leaves do not wither. Girdling does,
however, interfere with the downward food current through the bark.
[Illustration: FIG. 28 MOVEMENT OF THE SAP CURRENT]
If the tree be girdled the roots sooner or later suffer from lack of
food supply from the leaves. Owing to this food stoppage the roots will
cease to grow and will soon be unable to take in sufficient water, and
then the leaves will begin to droop. This, however, may not happen until
several months after the girdling. Sometimes a partly girdled branch
grows much in thickness just above the girdle, as is shown in Fig. 29.
This extra growth seems to be due to a stoppage of the rich supply of
food which was on its way to the roots through the bark. It could go no
farther and was therefore used by the tree to make an unnatural growth
at this point. You will now understand how and why trees die when they
are girdled to clear new ground.
[Illustration: FIG. 29. A THICKENING ABOVE THE WIRE THAT CAUSED THE
GIRDLING]
It is, then, the general law of sap-movement that the upward current
from the roots passes through the woody portion of the trunk, and that
the current bearing the food made by the leaves passes downward through
the bark.
=EXERCISE=
Let the teacher see that these and all other experiments are
performed by the pupils. Do not allow them to guess, but make them
see.
Girdle valueless trees or saplings of several kinds, cutting the
bark away in a complete circle around the tree. Do not cut into the
wood. How long before the tree shows signs of injury? Girdle a
single small limb on a tree. What happens? Explain.
SECTION XIV. THE FLOWER AND THE SEED
Some people think that the flowers by the wayside are for the purpose of
beautifying the world and increasing man's enjoyment. Do you think this
is true? Undoubtedly a flower is beautiful, and to be beautiful is one
of the uses of many flowers; but it is not the chief use of a flower.
You know that when peach or apple blossoms are nipped by the spring
frost the fruit crop is in danger. The fruit of the plant bears the
seed, and the flower produces the fruit. That is its chief duty.
[Illustration: FIG. 30. PARTS OF THE PISTIL]
Do you know any plant that produces seed without flowers? Some one
answers, "The corn, the elm, and the maple all produce seed, but have no
flower." No, that is not correct. If you look closely you will find in
the spring very small flowers on the elm and on the maple, while the ear
and the tassel are really the blossoms of the corn plant. Every plant
that produces seed has flowers, although they may sometimes seem very
curious flowers.
[Illustration: FIG. 31. A BUTTERCUP]
Let us see what a flower really is. Take, for example, a buttercup,
cotton, tobacco, or plum blossom (see Figs. 31 and 32). You will find on
the outside a row of green leaves inclosing the flower when it is still
a bud. These leaves are the _sepals_. Next on the inside is a row of
colored leaves, or _petals_. Arranged inside of the petals are some
threadlike parts, each with a knob on the end. These are the _stamens_.
Examine one stamen closely (Fig. 33). On the knob at its tip you should
find, if the flower is fully open, some fine grains, or powder. In the
lily this powder is so abundant that in smelling the flower you often
brush a quantity of it off on your nose. This substance is called
_pollen_, and the knob on the end of the stamen, on which the pollen is
borne, is the _anther_.
[Illustration: FIG. 32. A PLUM BLOSSOM]
The pollen is of very great importance to the flower. Without it there
could be no seeds. The stamens as pollen-bearers, then, are very
important. But there is another part to each flower that is of equal
value. This part you will find in the center of the flower, inside the
circle of stamens. It is called the _pistil_ (Fig. 32). The swollen tip
of the pistil is the _stigma_. The swollen base of the pistil forms the
_ovary_. If you carefully cut open this ovary you will find in it
very small immature seeds.
[Illustration: FIG. 33. STAMENS
_a_, anther; _f_, filament]
Some plants bear all these parts in the same flower; that is, each
blossom has stamens, pistil, petals, and sepals. The pear blossom and
the tomato blossom represent such flowers. Other plants bear their
stamens and pistils in separate blossoms. Stamens and pistils may even
occur in separate plants, and some blossoms have no sepals or petals at
all. Look at the corn plant. Here the tassel is a cluster of many
flowers, each of which bears only stamens. The ear is likewise a cluster
of many flowers, each of which bears only a pistil. The dust that you
see falling from the tassel is the pollen, and the long silky threads of
the ear are the stigmas.
[Illustration: FIG. 34. A TOMATO BLOSSOM]
Now no plant can bear seeds unless the pollen of the stamen falls on the
stigma. Corn cannot therefore form seed unless the dust of the tassel
falls upon the silk. Did you ever notice how poorly the cob is filled on
a single cornstalk standing alone in a field? Do you see why? It is
because when a plant stands alone the wind blows the pollen away from
the tassel, and little or none is received on the stigmas below.
[Illustration: FIG. 35. CUCUMBER BLOSSOMS]
In the corn plant the stamens and pistils are separate; that is, they do
not occur on the same flower, although they are on the same plant. This
is also true of the cucumber (see Fig. 35). In many plants, however,
such as the hemp, hop, sassafras, willow, and others, the staminate
parts are on one plant and the pistillate parts are on another. This is
also true in several other cultivated plants. For example, in some
strawberries the stamens are absent or useless; that is, they bear no
good pollen. In such cases the grower must see to it that near by are
strawberry plants that bear stamens, in order that those plants which do
not bear pollen may become _pollinated_; that is, may have pollen
carried to them. After the stigma has been supplied with pollen, a
single pollen grain sends a threadlike sprout down through the stigma
into the ovary. This process, if successfully completed, is called
_fertilization_.
=EXERCISE=
Examine several flowers and identify the parts named in the last
section. Try in the proper season to find the pollen on the maple,
willow, alder, and pine, and on wheat, cotton, and the
morning-glory.
How fast does the ovary of the apple blossom enlarge? Measure one
and watch it closely from day to day. Can you find any plants that
have their stamens and ovaries on separate individuals?
SECTION XV. POLLINATION
Nature has several interesting ways of bringing about pollination. In
the corn, willow, and pine the pollen is picked up by the wind and
carried away. Much of it is lost, but some reaches the stigmas, or
receptive parts, of other corn, willow, or pine flowers. This is a very
wasteful method, and all plants using it must provide much pollen.
Many plants employ a much better method. They have learned how to make
insects bear their pollen. In plants of this type the parts of the
blossom are so shaped and so placed as to deposit pollen from the stamen
on the insect and to receive pollen from the insect on the stigmas.
When you see the clumsy bumblebee clambering over and pushing his way
into a clover blossom, you may be sure that he is getting well dusted
with pollen and that the next blossom which he visits will secure a full
share on its stigmas.
When flowers fit themselves to be pollinated by insects they can no
longer use the wind and are helpless if insects do not visit them. They
therefore cunningly plan two ways to invite the visits of insects.
First, they provide a sweet nectar as a repast for the insect visitor.
The nectar is a sugary solution found in the bottom of the flower and is
used by the visitor as food or to make honey. Second, flowers advertise
to let each insect know that they have something for it. The advertising
is done either by showy colors or by perfume. Insects have wonderful
powers of smell. When you see showy flowers or smell fragrant ones, you
will know that such flowers are advertising the presence either of
nectar or of pollen (to make beebread) and that such flowers depend on
insects for pollination.
[Illustration: FIG. 36. BEES CARRYING POLLEN]
A season of heavy, cold rains during blossoming-time may often injure
the fruit crop by preventing insects from carrying pollen from flower to
flower. You now also understand why plants often fail to produce seeds
indoors. Since they are shut in, they cannot receive proper insect
visits. Plants such as tomatoes or other garden fruits dependent upon
insect pollination must, if raised in the greenhouse where insects
cannot visit them, be pollinated by hand.
=EXERCISE=
Exclude insect visitors from some flower or flower cluster, for
example, clover, by covering with a paper bag, and see whether the
flower can produce seeds that are capable of growing. Compare as to
number and vitality the seeds of such a flower with those of an
uncovered flower. Observe insects closely. Do you ever find pollen
on them? What kinds of insects visit the clover? the cowpea? the
sourwood? the flax? Is wheat pollinated by insects or by the wind
or by some other means? Do bees fly in rainy weather? How will a
long rainy season at blossoming-time affect the apple crop? Why?
Should bees be kept in an orchard? Why?
SECTION XVI. CROSSES, HYBRIDS, AND CROSS-POLLINATION
In our study of flowers and their pollination we have seen that the seed
is usually the descendant of two parents, or at least of two organs--one
the ovary, producing the seed; the other the pollen, which is necessary
to fertilize the ovary.
It happens that sometimes the pollen of one blossom fertilizes the ovary
of its own flower, but more often the pollen from one plant fertilizes
the ovary of another plant. This latter method is called
_cross-pollination_. As a rule cross-pollination makes seed that will
produce a better plant than simple pollination would. Cross-pollination
by hand is often used by plant-breeders when, for purposes of
seed-selection, a specially strong plant is desired. The steps in hand
pollination are as follows: (1) remove the anthers before they open, to
prevent them from pollinating the stigma (the steps in this process are
illustrated in Figs. 37, 38-39); (2) cover the flower thus treated with
a paper bag to prevent stray pollen from getting on it (see Fig. 40);
(3) when the ovary is sufficiently developed, carry pollen to the stigma
by hand from the anthers of another plant which you have selected to
furnish it, and rebag to keep out any stray pollen which might
accidentally get in; (4) collect the seeds when they are mature and
label them properly.
Hand pollination has this advantage--you know both parents of your seed.
If pollination occur naturally you know the maternal but have no means
of judging the paternal parent. You can readily see, therefore, how hand
pollination enables you to secure seed derived from two well-behaved
parents.
Sometimes we can breed one kind of plant on another. The result of such
cross-breeding is known as a _hybrid_. In the animal kingdom the mule is
a common example of this cross-breeding. Plant hybrids were formerly
called mules also, but this suggestive term is almost out of use.
[Illustration: FIG. 37
The bud on right at top is in proper condition for removal of anthers;
the anthers have been removed from the buds below]
It is only when plants of two distinct kinds are crossed that the result
is called a hybrid; for example, a blackjack oak on a white oak, an
apple on a pear. If the parent plants are closely related, for example,
two kinds of apples, the resulting plant is known simply as a _cross_.
Hybrids and crosses are valuable in that they usually differ from both
parents and yet combine some qualities of each.
[Illustration: FIG. 38. ORANGE BLOSSOM PREPARED FOR CROSSING
First, bud; second, anthers unremoved; third, anthers removed]
[Illustration: FIG. 39. TOMATO BLOSSOM READY TO CROSS
First, bud; second, anthers unremoved; third, anthers removed]
[Illustration: FIG. 40.
First, blossom bagged to keep out stray pollen; second, fruit bagged for
protection]
They often leave off some of the qualities of the parent
plants and at other times have such qualities more markedly than did
their parents. Thus they often produce an interesting new kind of plant.
Sometimes we are able by hybridization to combine in one plant the good
qualities of two other plants and thus make a great advance in
agriculture. The new forms brought about by hybridization may be fixed,
or made permanent, by such selection as is mentioned in Section XVIII.
Hybridization is of great aid in originating new plants.
It often happens that a plant will be more fruitful when pollinated by
one variety than by some other variety. This is well illustrated in Fig.
41. A fruit-grower or farmer should know much about these subjects
before selecting varieties for his orchard, vineyard, etc.
=EXERCISE=
With the help of your teacher try to cross some plants. Such an
experiment will take time, but will be most interesting. You must
remember that many crosses must be attempted in order to gain
success with even a few.
SECTION XVII. PROPAGATION BY BUDS
It is the business of the farmer to make plants grow, or, as it is
generally called, to propagate plants. This he does in one of two ways:
by buds (that is, by small pieces cut from parent plants), or by seeds.
The chief aim in both methods should be to secure in the most convenient
manner the best-paying plants.
Many plants are most easily and quickly propagated by buds; for example,
the grape, red raspberry, fig, and many others that we cultivate for the
flower only, such as the carnation, geranium, rose, and begonia.
[Illustration: FIG. 41.
Brighton pollinated by 1, Salem; 2, Creveling; 3, Lindley; 4, Brighton;
5, Self-pollinated; 6, Nectar; 7, Jefferson; 8, Niagara]
In growing plants from cuttings, a piece is taken from the kind of plant
that one wishes to grow. The greatest care must be exercised in order to
get a healthy cutting. If we take a cutting from a poor plant, what can
we expect but to grow a poor plant like the one from which our cutting
was taken? On the other hand, if a fine, strong, vigorous, fruitful
plant be selected, we shall expect to grow just such a fine, healthy,
fruitful plant.
We expect the cutting to make exactly the same variety of plant as the
parent stock. We must therefore decide on the variety of berry, grape,
fig, carnation, or rose that we wish to propagate, and then look for the
strongest and most promising plants of this variety within our reach.
The utmost care will not produce a fine plant if we start from poor
stock.
[Illustration: FIG. 42. GERANIUM CUTTING
Dotted line shows depth to which cutting should be planted]
What qualities are most desirable in a plant from which cuttings are to
be taken? First, it should be productive, hardy, and suited to your
climate and your needs; second, it should be healthy. Do not take
cuttings from a diseased plant, since the cutting may carry the
disease.
Cuttings may be taken from various parts of the plant, sometimes even
from parts of the leaf, as in the begonia (Fig. 46). More often,
however, they are drawn from parts of the stem (Figs. 43-45). As to the
age of the twig from which the cutting is to be taken, Professor Bailey
says: "For most plants the proper age or maturity of wood for the making
of cuttings may be determined by giving the twig a quick bend; if it
snaps and hangs by the bark, it is in proper condition. If it bends
without breaking, it is too young and soft or too old. If it splinters,
it is too old and woody." Some plants, as the geranium (Fig. 42),
succeed best if the cuttings from which they are grown are taken from
soft, young parts of the plant; others, for example, the grape or rose,
do better when the cutting is made from more mature wood.
[Illustration: FIG. 43 GRAPE CUTTING
Showing depth to which cutting should be planted]
[Illustration: FIG. 44. CARNATION CUTTING]
Cuttings may vary in size and may include one or more buds. After a
hardy, vigorous cutting is made, insert it about one half or one third
of its length in soil. A soil free from organic matter is much the best,
since in such soil the cuttings are much less liable to disease. A fine,
clean sand is commonly used by professional gardeners. When cuttings
have rooted well--this may require a month or more--they may be
transplanted to larger pots.
Sometimes, instead of cutting off a piece and rooting it, portions of
branches are made to root before they are separated from the parent
plant. This method is often followed, and is known as _layering_. It is
a simple process. Just bend the tip of a bough down and bury it in the
earth (see Fig. 47). The black raspberry forms layers naturally, but
gardeners often aid it by burying the over-hanging tips in the earth, so
that more tips may easily take root. Strawberries develop runners that
root themselves in a similar fashion.
Grafts and buds are really cuttings which, instead of being buried in
sand to produce roots of their own, are set on the roots of other
plants.
[Illustration: FIG. 45. ROSE CUTTING]
Grafting and budding are practiced when these methods are more
convenient than cuttings or when the gardener thinks there is danger of
failure to get plants to take root as cuttings. Neither grafting nor
budding is, however, necessary for the raspberry or the grape, for these
propagate most readily from cuttings.
It is often the case that a budded or grafted plant is more fruitful
than a plant on its own roots. In cases of this kind, of course, grafts
or buds are used.
The white, or Irish, potato is usually propagated from pieces of the
potato itself. Each piece used for planting bears one eye or more. The
potato itself is really an underground stem and the eyes are buds. This
method of propagation is therefore really a peculiar kind of cutting.
Since the eye is a bud and our potato plant for next year is to develop
from this bud, it is of much importance, as we have seen, to know
exactly what _kind_ of plant our potato comes from. If the potato is
taken from a small plant that had but a few poor potatoes in the hill,
we may expect the bud to produce a similar plant and a correspondingly
poor crop. We must see to it, then, that our seed potatoes are drawn
from vines that were good producers, because new potato plants are like
the plants from which they were grown. Of course when our potatoes are
in the bin we cannot tell from what kind of plants they came. We must
therefore _select our seed potatoes in the field_. Seed potatoes should
always be selected from those hills that produce most bountifully. Be
assured that the increased yield will richly repay this care in
selecting. It matters not so much whether the seed potato be large or
small; it must, however, come from a hill bearing a large yield of fine
potatoes.
[Illustration: FIG. 46. BEGONIA-LEAF CUTTING]
Sweet-potato plants are produced from shoots, or growing buds, taken
from the potato itself, so that in their case too the piece that we use
in propagating is a part of the original plant, and will therefore be
like it under similar conditions. Just as with the Irish potato, it is
important to know how good a yielder you are planting. You should watch
during harvest and select for propagation for the next year only such
plants as yield best.
We should exercise fully as much care in selecting proper individuals
from which to make a cutting or a layer as we do in selecting a proper
animal to breed from. Just as we select the finest Jersey in the herd
for breeding purposes, so we should choose first the variety of plant we
desire and then the finest individual plant of that variety.
If the variety of the potato that we desire to raise be Early Rose, it
is not enough to select _any_ Early Rose plants, but the very best Early
Rose plants, to furnish our seed.
[Illustration: FIG. 47. LAYERING]
It is not enough to select large, fine potatoes for cuttings. A large
potato may not produce a bountifully yielding plant. _It will produce a
plant like the one that produced it._ It may be that this one large
potato was the only one produced by the original plant. If so, the plant
that grows from it will tend to be similarly unproductive. Thus you see
the importance of _selecting in the field a plant that has exactly the
qualities desired in the new plant_.
One of the main reasons why gardeners raise plants from buds instead of
from seeds is that the seed of many plants will not produce plants like
the parent. This failure to "come true," as it is called, is sometimes
of value, for it occasionally leads to improvement. For example, suppose
that a thousand apple or other fruit or flower seeds from plants usually
propagated by cuttings be planted; it may be that one out of a thousand
or a million will be a very valuable plant. If a valuable plant be so
produced, it should be most carefully guarded, multiplied by cuttings or
grafts, and introduced far and wide. It is in this way that new
varieties of fruits and flowers are produced from time to time.
Sometimes, too, a single bud on a tree will differ from the other buds
and will produce a branch different from the other branches. This is
known as _bud variation_. When there is thus developed a branch which
happens to be of a superior kind, it should be propagated by cuttings
just as you would propagate it if it had originated from a seed.
[Illustration: FIG. 48. CURRANT CUTTING]
Mr. Gideon of Minnesota planted many apple seeds, and from them all
raised one tree that was very fruitful, finely flavored, and able to
withstand the cold Minnesota winter. This tree he multiplied by grafts
and named the Wealthy apple. It is said that in giving this one apple to
the world he benefited mankind to the value of more than one million
dollars. It will be well to watch for any valuable bud or seed variant
and never let a promising one be lost. Plants grown in this way from
seeds are usually spoken of as seedlings.
[Illustration: A LUSCIOUS AND EASILY GROWN BERRY]
PLANTS TO BE PROPAGATED FROM BUDS
The following list gives the names and methods by which our common
garden fruits and flowers are propagated:
_Figs_: use cuttings 8 to 10 inches long or layer.
_Grapes_: use long cuttings, layer, or graft upon old vines.
_Apples_: graft upon seedlings, usually crab seedlings one
year old.
_Pears_: bud upon pear seedlings.
_Cherries_: bud upon cherry stock.
_Plums_: bud upon peach stock.
_Peaches_: bud upon peach or plum seedlings.
_Quinces_: use cuttings or layer.
_Blackberries_: propagate by suckers; cut from parent stem.
_Black raspberries_: layer; remove old stem.
_Red raspberries_: propagate by root-cuttings or suckers.
_Strawberries_: propagate by runners.
_Currants_ and _gooseberries_: use long cuttings (these plants
grow well only in cool climates; if attempted in warm
climates, set in cold exposure).
_Carnations_, _geraniums_, _roses_, _begonias_, etc.: propagate by
cuttings rooted in sand and then transplanted to small pots.
=EXERCISE=
Propagate fruits (grape, fig, strawberry) of various kinds; also
ornamental plants. How long does it take them to root? Geraniums
rooted in the spring will bloom in the fall. Do you know any one
who selects seed potatoes properly? Make a careful selection of
seed at the next harvest-time.
SECTION XVIII. PLANT SEEDING
In propagating by seed, as in reproducing by buds, we select a portion
of the parent plant--for a seed is surely a part of the parent
plant--and place it in the ground. There is, however, one great
difference between a seed and a bud. The bud is really a piece of the
parent plant, but a piece of _one_ plant only, while a seed comes from
the parts of two plants.
You will understand this fully if you read carefully Sections XIV-XVI.
Since the seed is made of two plants, the plant that springs from a seed
is much more likely to differ from its mother plant, that is, from the
plant that produces the seed, than is a plant produced merely by buds.
In some cases plants "come true to seed" very accurately. In others they
vary greatly. For example, when we plant the seed of wheat, turnips,
rye, onions, tomatoes, tobacco, or cotton, we get plants that are in
most respects like the parent plant. On the other hand the seed of a
Crawford peach or a Baldwin apple or a Bartlett pear will not produce
plants like its parent, but will rather resemble its wild forefathers.
These seedlings, thus taking after their ancestors, are always far
inferior to our present cultivated forms. In such cases seeding is not
practicable, and we must resort to bud propagation of one sort or
another.
While in a few plants like those just mentioned the seed does not "come
true," most plants, for example, cotton, tobacco, and others, do "come
true." When we plant King cotton we may expect to raise King cotton.
There will be, however, as every one knows, some or even considerable
variation in the field. Some plants, even in exactly the same soil, will
be better than the average, and some will be poorer. Now we see this
variation in the plants of our field, and we believe that the plant will
be in the main like its parent. What should we learn from this? Surely
that if we wish to produce sturdy, healthy, productive plants we must go
into our fields and _pick out just such plants to secure seed from as we
wish to produce another year_. If we wait until the seed is separated
from the plant that produced it before we select our cotton seed, we
shall be planting seed from poor as well as from good plants, and must
be content with a crop of just such stock as we have planted. By
selecting seed from the most productive plants _in the field_ and by
repeating the selection each year, you can continually improve the breed
of the plant you are raising. In selecting seed for cotton you may
follow the plan suggested below for wheat.
[Illustration: FIGS. 49 AND 50. CHRYSANTHEMUMS AND ASPARAGUS]
The difference that you see between the wild and the cultivated
chrysanthemums and between the samples of asparagus shown in Figs. 49
and 50 was brought about by just such continuous seed-selection from the
kind of plant wanted.
[Illustration: FIG. 51. TWO VARIETIES OF FLAX FROM ONE PARENT STOCK]
By the careful selection of seed from the longest flax plants the
increase in length shown in the accompanying figure was gained. The
selection of seed from those plants bearing the most seed, regardless of
the height of the plant, has produced flax like that to the right in the
illustration. These two kinds of flax are from the same parent stock,
but slight differences have been emphasized by continued seed-selection,
until we now have really two varieties of flax, one a heavy seed-bearer,
the other producing a long fiber.
You can in a similar way improve your cotton or any other seed crop.
Sugar beets have been made by seed-selection to produce about double the
percentage of sugar that they did a few years ago. Preparing and
tilling land costs too much in money and work to allow the land to be
planted with poor seed. When you are trying by seed-selection to
increase the yield of cotton, there are two principles that should be
borne in mind: first, seed should be chosen only from plants that bear
many well-filled bolls of long-staple cotton; second, seed should be
taken from no plant that does not by its healthy condition show
hardihood in resisting disease and drouth.
The plan of choosing seeds from selected plants may be applied to wheat;
but it would of course be too time-consuming to select enough single
wheat plants to furnish all of the seed wheat for the next year. In this
case adopt the following plan: In Fig. 52 let _A_ represent the total
size of your wheat field and let _B_ represent a plat large enough to
furnish seed for the whole field. At harvest-time go into section _A_
and select the best plants you can find. Pick the heads of these and
thresh them by hand. The seed so obtained must be carefully saved for
your next sowing.
[Illustration: FIG. 52.]
In the fall sow these selected seeds in area _B_. This area should
produce the best wheat. At the next harvest cull not from the whole
field but from the finest plants of plat _B_, and again save these as
seed for plat _B_. Use the unculled seed from plat _B_ to sow your crop.
By following this plan continuously you will every year have seed from
several generations of choice plants, and each year you will improve
your seed.
It is of course advisable to move your seed plat _B_ every year or two.
For the new plat select land that has recently been planted in legumes.
Always give this plat unwearying care.
In the selection of plants from which to get seed, you must know what
kind of plants are really the best seed plants. First, _you must not
regard single heads or grains, but must select seed from the most
perfect plant_, looking at the plant as a whole and not at any single
part of it. A first consideration is yield. Select the plants that yield
best and are at the same time resistant to drouth, resistant to rust and
to winter, early to ripen, plump of grain, and nonshattering. What a
fine thing it would be to find even one plant free from rust in the
midst of a rusted field! It would mean a _rust-resistant plant_. Its
offspring also would probably be rust-resistant. If you should ever find
such a plant, be sure to save its seed and plant it in a plat by itself.
The next year again save seed from those plants least rusted. Possibly
you can develop a rust-proof race of wheat! Keep your eyes open.
In England the average yield of wheat is thirty bushels an acre, in the
United States it is less than fifteen bushels! In some states the yield
is even less than nine bushels an acre. Let us select our seed with
care, as the English people do, and then we can increase our yield. By
careful seed-selection a plant-breeder in Minnesota increased the yield
of his wheat by one fourth. Think what it would mean if twenty-five per
cent were added to the world's supply of wheat at comparatively no cost;
that is, at the mere cost of careful seed-selection. This would mean an
addition to the world's income of about $500,000,000 each year. The
United States would get about one fifth of this profit.
It often happens that a single plant in a crop of corn, cotton, or wheat
will be far superior to all others in the field. Such a plant deserves
special care. Do not use it merely as a seed plant, but carefully plant
its seeds apart and tend carefully. The following season select the best
of its offspring as favorites again. Repeat this selection and culture
for several years until you fix the variety. This is the way new
varieties are originated from plants propagated by seed.
In 1862 Mr. Abraham Fultz of Pennsylvania, while passing through a field
of bearded wheat, found three heads of beardless, or bald, wheat. These
he sowed by themselves that year, and as they turned out specially
productive he continued to sow this new variety. Soon he had enough seed
to distribute over the country. It became known as the Fultz wheat and
is to-day one of the best varieties in the United States and in a number
of foreign countries. Think how many bushels of wheat have been added to
the world's annual supply by a few moments of intelligent observation
and action on the part of this one man! He saw his opportunity and used
it. How many similar opportunities do you think are lost? How much does
your state or country lose thereby?
=EXERCISE=
Select one hundred seeds from a good, and one hundred from a poor,
plant of the same variety. Sow them in two plats far enough apart
to avoid cross-pollination, yet try to have soil conditions about
the same. Give each the same care and compare the yield. Try this
with corn, cotton, and wheat. Select seeds from the best plant in
your good plat and from the poorest in your poor plat and repeat
the experiment. This will require but a few feet of ground, and the
good plat will pay for itself in yield, while the poor plat will
more than pay in the lesson that it will teach you.
Write to the Department of Agriculture, Washington, D.C., and to
your state experiment station for bulletins concerning
seed-selection and methods of plant-improvement.
SECTION XIX. SELECTING SEED CORN
If a farmer would raise good crops he must, as already stated, select
good seed. Many of the farmer's disappointments in the quantity and
quality of his crops--disappointments often thought to come from other
causes--are the result of planting poor seed. Seeds not fully ripened,
if they grow at all, produce imperfect plants. Good seed, therefore, is
the first thing necessary for a good crop. The seed of perfect plants
only should be saved.
By wise and persistent selection, made in the field before the crop is
fully matured, corn can be improved in size and made to mature earlier.
Gather ears only from the most productive plants and save only the
largest and best kernels.
[Illustration: FIG. 53. THE KIND OF EAR TO SELECT]
You have no doubt seen the common American blackbirds that usually
migrate and feed in such large numbers. They all look alike in every
way. Now, has it ever occurred to you to ask why all blackbirds are
black? The blackbirds are black simply because their parents are black.
Now in the same way that the young blackbirds resemble their parents,
corn will resemble its parent stock. How many ears of corn do you find
on a stalk? One, two, sometimes three or four. You find two ears of corn
on a stalk because it is the nature of that particular stalk to produce
two ears. In the same way the nature of some stalks is to produce but
one ear, while it is the nature of others sometimes to produce two or
more.
This resemblance of offspring to parent is known to scientists as
heredity, or as "like producing like."
Some Southern corn-breeders take advantage of this law to improve their
corn crop. If a stalk can be made to produce two ears of corn just as
large as the single ear that most stalks bear, we shall get twice as
much corn from a field in which the "two-eared" variety is planted. In
the North and West the best varieties of corn have been selected to make
but one ear to the stalk. It is generally believed that this is the best
practice for the shorter growing seasons of the colder states.
[Illustration: FIG. 54. SELECT SEED FROM A STALK LIKE THAT ON LEFT]
These facts ought to be very helpful to us next year when our fathers
are planting corn. We should get them to plant seed secured only from
stalks that produced the most corn, whether the stalk had two or more
ears or only one. If we follow this plan year by year, each acre of land
will be made to produce more kernels and hence a larger crop of corn,
and yet no more work will be required to raise the crop.
In addition to enlarging the yield of corn, you can, by proper selection
of the best and most productive plants in the field, grow a new variety
of seed corn. To do this you need only take the largest and best
kernels from stalks bearing two ears; plant these, and at the next
harvest again save the best kernels from stalks bearing the best ears.
If you keep up this practice with great care for several years, you will
get a vigorous, fruitful variety that will command a high price for
seed.
=EXPERIMENT=
[Illustration: FIG. 55. IMPROVEMENT OF CORN BY SELECTION
Boone County white corn on left, and original type, from which it
was developed by selection, on right]
Every school boy and girl can make this experiment at leisure. From
your own field get two ears of corn, one from a stalk bearing only
one ear and the other from a stalk bearing two well-grown ears.
Plant the grains from one ear in one plat, and the grains from the
other in a plat of equal size. Use for both the same soil and the
same fertilizer. Cultivate both plats in the same way. When the
crop is ready to harvest, husk the corn, count the ears, and weigh
the corn. Then write a short essay on your work and on the results
and get your teacher to correct the story for your home paper.
SECTION XX. WEEDS
Have you ever noticed that some weeds are killed by one particular
method, but that this same method may entirely fail to kill other kinds
of weeds? If we wish to free our fields of weeds with the greatest ease,
we must know the nature of each kind of weed and then attack it in the
way in which we can most readily destroy it.
[Illustration: FIG. 56. PIGWEED]
The ordinary pigweed (Fig. 56) differs from many other weeds in that it
lives for only one year. When winter comes, it must die. Each plant,
however, bears a great number of seeds. If we can prevent the plant from
bearing seed in its first year, there will not be many seeds to come up
the next season. In fact, only those seeds that were too deeply buried
in the soil to come up the previous spring will be left, and of these
two-year-old seeds many will not germinate. During the next season some
old seeds will produce plants, but the number will be very much
diminished. If care be exercised to prevent the pigweed from seeding
again, and the same watchfulness be continued for a few seasons, this
weed will be almost entirely driven from our fields.
A plant like the pigweed, which lives only one year, is called an
_annual_ and is one of the easiest weeds to destroy. Mustard, plantain,
chess, dodder, cockle, crab grass, and Jimson weed are a few of our most
disagreeable annual weeds.
The best time to kill any weed is when it is very small; therefore the
ground in early spring should be constantly stirred in order to kill the
young weeds before they grow to be strong and hardy.
[Illustration: FIG. 57. WILD CARROT]
The wild carrot differs from an annual in this way: it lives throughout
one whole year without producing seeds. During its first year it
accumulates a quantity of nourishment in the root, then rests in the
winter. Throughout the following summer it uses this nourishment rapidly
to produce its flowers and seeds. Then the plant dies. Plants that live
through two seasons in this way are called _biennials_. Weeds of this
kind may be destroyed by _cutting the roots below the leaves_ with a
grubbing-hoe or spud. A spud may be described as a chisel on a long
handle (see Fig. 58). If biennials are not cut low enough they will
branch out anew and make many seeds. Among the most common biennials are
the thistle, moth mullein, wild carrot, wild parsnip, and burdock.
[Illustration: FIG. 58. A SPUD]
[Illustration: FIG. 59. HOUND'S TONGUE]
A third group of weeds consists of those that live for more than two
years. These weeds are usually most difficult to kill. They propagate by
means of running rootstocks as well as by seeds. Plants that live more
than two seasons are known as _perennials_ and include, for example,
many grasses, dock, Canada thistle, poison ivy, passion flower, horse
nettle, etc. There are many methods of destroying perennial weeds. They
may be dug entirely out and removed. Sometimes in small areas they may
be killed by crude sulphuric acid or may be starved by covering them
with boards or a straw stack or in some other convenient way. A method
that is very effective is to smother the weeds by a dense growth of
some other plant, for example, cowpeas or buckwheat. Cowpeas are to be
preferred, since they also enrich the soil by the nitrogen that the
root-tubercles gather.
[Illustration: FIG. 60. CANADA THISTLE]
Weeds do injury in numerous ways; they shade the crop, steal its
nourishment, and waste its moisture. Perhaps their only service is to
make lazy people till their crops.
=EXERCISE=
You should learn to know by name the twenty worst weeds of your
vicinity and to recognize their seeds. If there are any weeds you
are not able to recognize, send a sample of each to your state
experiment station. Make a collection, properly labeled, of weeds
and weed seeds for your school.
SECTION XXI. SEED PURITY AND VITALITY
Seeds produce plants. The difference between a large and a small yield
may depend upon the kind of plants we raise, and the kind of plant in
turn is dependent upon the seeds that we sow.
Two things are important in the selection of seeds--purity and vitality.
Seeds should be _pure_; that is, when sown they should produce no other
plant than the one that we wish to raise. They should be able to grow.
The ability of a seed to grow is termed its _vitality_. Good seed should
be nearly or quite pure and should possess high vitality. The vitality
of seeds is expressed as a per cent; for example, if 97 seeds out of 100
germinate, or sprout, the vitality is said to be 97. The older the seed
the less is its vitality, except in a few rare instances in which seeds
cannot germinate under two or three years.
Cucumber seeds may show 90 per cent vitality when they are one year old,
75 per cent when two years old, and 70 per cent when three years
old--the per cent of vitality diminishing with increase of years. The
average length of life of the seeds of cultivated plants is short: for
example, the tomato lives four years; corn, two years; the onion, two
years; the radish, five years. The cucumber seed may retain life after
ten years; but the seeds of this plant too lose their vitality with an
increase in years.
It is important when buying seeds to test them for purity and vitality.
Dealers who are not honest often sell old seeds, although they know that
seeds decrease in value with age. Sometimes, however, to cloak
dishonesty they mix some new seeds with the old, or bleach old and
yellow seeds in order to make them resemble fresh ones.
It is important, therefore, that all seeds bought of dealers should be
thoroughly examined and tested; for if they do not grow, we not only pay
for that which is useless but we are also in great danger of producing
so few plants in our fields that we shall not get full use of the land,
and thus we may suffer a more serious loss than merely paying for a few
dead seeds. It will therefore be both interesting and profitable to
learn how to test the vitality of seeds.
To test vitality plant one hundred seeds in a pot of earth or in damp
sand, or place them between moist pieces of flannel, and take care to
keep them moist and warm. Count those that germinate and thus determine
the percentage of vitality. Germinating between flannel is much quicker
than planting in earth. Care should be used to keep mice away from
germinating seeds. (See Fig. 61.)
[Illustration: FIG. 61. A SEED-GERMINATOR
Consisting of two soup plates, some sand, and a piece of cloth]
Sometimes the appearance of a package will show whether the seed has
been kept in stock a long time. It is, however, much more difficult to
find out whether the seeds are pure. You can of course easily
distinguish seeds that differ much from those you wish to plant, but
often certain weed seeds are so nearly like certain crop seeds as not to
be easily recognized by the eye. Thus the dodder or "love vine," which
so often ruins the clover crop, has seeds closely resembling clover
seeds. The chess, or cheat, has seeds so nearly like oats that only a
close observer can tell them apart. However, if you watch the seeds that
you buy, and study the appearance of crop seeds, you may become expert
in recognizing those that have no place in your planting.
One case is reported in which a seed-dealer intentionally allowed an
impurity of 30 per cent to remain in the crop seeds, and this impurity
was mainly of weed seeds. There were 450,000 of one kind and 288,000 of
another in each pound of seed. Think of planting weeds at that rate!
Sometimes three fourths of the seeds you buy are weed seeds.
In purchasing seeds the only safe plan is to buy of dealers whose
reputation can be relied upon.
It not seldom happens that seeds, like corn, are stored in open cribs or
barns before the moisture is entirely dried out of the seeds. Such seeds
are liable to be frozen during a severe winter, and of course if this
happens they will not sprout the following spring. The only way to tell
whether such seeds have been killed is to test samples of them for
vitality. Testing is easy; replanting is costly and often results in a
short crop.
[Illustration: FIG. 62. IMPURITIES IN SEEDS
Tube 1 represents one pound of redtop grass as bought; Tube 2, amount of
pure redtop grass seeds in Tube 1; Tube 3, amount of chaff and dirt in
Tube 1; Tube 4, amount of weed seeds in Tube 1; Tube 5, amount of total
waste in Tube 1; Tube 6, amount of pure germinable seeds in Tube 1]
=EXERCISE=
Examine seeds both for vitality and purity. Write for farmers'
bulletins on both these subjects. What would be the loss to a
farmer who planted a ten-acre clover field with seeds that were 80
per cent bad? Can you recognize the seeds of the principal
cultivated plants? Germinate some beet seeds. What per cent comes
up? Can you explain? Collect for your school as many kinds of wild
and cultivated seeds as you can.
CHAPTER IV
HOW TO RAISE A FRUIT TREE
Let each pupil grow an apple tree this year and attempt to make it the
best in his neighborhood. In your attempt suppose you try the following
plan. In the fall take the seed of an apple--a crab-apple is good--and
keep it in a cool place during the winter. The simplest way to do this
is to bury it in damp sand. In the spring plant it in a rich, loose
soil.
Great care must be taken of the young shoot as soon as it appears above
the ground. You want to make it grow as tall and as straight as possible
during this first year of its life, hence you should give it rich soil
and protect it from animals. Before the ground freezes in the fall take
up the young tree with the soil that was around it and keep it all
winter in a cool, damp place.
Now when spring comes it will not do to set out the carefully tended
tree, for an apple tree from seed will not be a tree like its parent,
but will tend to resemble a more distant ancestor. The distant ancestor
that the young apple tree is most likely to take after is the wild
apple, which is small, sour, and otherwise far inferior to the fruit we
wish to grow. It makes little difference, therefore, what kind of apple
seed we plant, since in any event we cannot be sure that the tree grown
from it will bear fruit worth having unless we force it to do so.
[Illustration: FIG. 63. A YOUNG FRUIT-GROWER]
SECTION XXII. GRAFTING
By a process known as _grafting_ you can force your tree to produce
whatever variety of apple you desire. Many people raise fruit trees
directly from seed without grafting. Thus they often produce really
worthless trees. By grafting they would make sure not only of having
good trees rather than poor ones but also of having the particular kind
of fruit that they wish. Hence you must now graft your tree.
First you must decide what variety of apple you want to grow on the
tree. The Magnum Bonum is a great favorite as a fall apple. The Winesap
is a good winter apple, while the Red Astrachan is a profitable early
apple, especially in the lowland of the coast region. The Northern Spy,
AEsop, and Spitzenburg are also admirable kinds. Possibly some other
apple that you know may suit your taste and needs better than any of
these varieties.
If you have decided to raise an AEsop or a Magnum Bonum or a Winesap, you
must now cut a twig from the tree of your choice and graft it upon the
little tree that you have raised. Choose a twig that is about the
thickness of the young tree at the point where you wish to graft. Be
careful to take the shoot from a vigorous, healthy part of the tree.
[Illustration: FIG. 64. TONGUE GRAFTING]
There are many ways in which you may join the chosen shoot or twig upon
the young tree, but perhaps the best one for you to use is known as
_tongue grafting_. This is illustrated in Fig. 64. The upper part, _b_,
which is the shoot or twig that you cut from the tree, is known as the
_scion_; the lower part, _a_, which is the original tree, is called the
_stock_.
Cut the scion and stock as shown in Fig. 64. Join the cut end of the
scion to the cut end of the stock. When you join them, notice that under
the bark of each there is a thin layer of soft, juicy tissue. This is
called the _cambium_. To make a successful graft the cambium in the
scion must exactly join the cambium in the stock. Be careful, then, to
see that cambium meets cambium. You now see why grafting can be more
successfully done if you select a scion and stock of nearly the same
size.
[Illustration: FIG. 65. A COMPLETED GRAFT
Showing scion and stock from which it was made]
After fitting the parts closely together, bind them with cotton yarn
(see Fig. 65) that has been coated with grafting wax. This wax is made
of equal parts of tallow, beeswax, and linseed oil. Smear the wax
thoroughly over the whole joint, and make sure that the joint is
completely air-tight.
[Illustration: FIG. 66.
To make a root graft, cut along the slanting line]
The best time to make this graft is when scion and stock are dormant,
that is, when they are not in leaf. During the winter, say in February,
is the best time to graft the tree. Set the grafted tree away again in
damp sand until spring, then plant it in loose, rich soil.
Since all parts growing above the graft will be of the same kind as the
scion, while all branches below it will be like the stock, it is well to
graft low on the stock or even upon the root itself. The slanting double
line in Fig. 66 shows the proper place to cut off for such grafting.
[Illustration: FIG. 67. A COMPLETED ROOT GRAFT]
If you like you may sometime make the interesting and valuable
experiment of grafting scions from various kinds of apple trees on the
branches of one stock. In this way you can secure a tree bearing a
number of kinds of fruit. You may thus raise the Bonum, Red Astrachan,
Winesap, and as many other varieties of apples as you wish, upon one
tree. For this experiment, however, you will find it better to resort to
_cleft grafting_, which is illustrated in Fig. 68.
[Illustration: FIG. 68. CLEFT GRAFTING]
Luther Burbank, the originator of the Burbank potato, in attempting to
find a variety of apple suited to the climate of California, grafted
more than five hundred kinds of apple scions on one tree, so that he
might watch them side by side and find out which kind was best suited to
that state.
SECTION XXIII. BUDDING
If, instead of an apple tree, you were raising a plum or a peach tree, a
form of propagation known as _budding_ would be better than grafting.
Occasionally budding is also employed for apples, pears, cherries,
oranges, and lemons. Budding is done in the following manner. A single
bud is cut from the scion and is then inserted under the bark of a
one-year-old peach seedling, so that the cambium of the bud and stock
may grow together.
[Illustration: FIG. 69. HOW TO CUT A BUD FROM A SCION]
[Illustration: FIG. 70. THE STEPS IN BUDDING]
Cut scions of the kind of fruit tree you desire from a one-year-old twig
of the same variety. Wrap them in a clean, moist cloth until you are
ready to use them. Just before using cut the bud from the scion, as
shown in Fig. 69. This bud is now ready to be inserted on the north side
of the stock, just two or three inches above the ground. The north side
is selected to avoid the sun. Now, as shown at _a_ in Fig. 70, make a
cross and an up-and-down incision, or cut, on the stock; pull the bark
back carefully, as shown in _B_; insert the bud _C_, as shown in _D_;
then fold the bark back and wrap with yarn or raffia, as shown in _E_.
As soon as the bud and branches have united, remove the wrapping to
prevent its cutting the bark and cut the tree back close to the bud, as
in Fig. 71, so as to force nourishment into the inserted bud.
[Illustration: FIG. 71.
Sloping line shows where to cut tree]
Budding is done in the field without disturbing the tree as it stands in
the ground. The best time to do budding is during the summer or fall
months, when the bark is loose enough to allow the buds to be easily
inserted.
Trees may be budded or grafted on one another only when they are nearly
related. Thus the apple, crab-apple, hawthorn, and quince are all
related closely enough to graft or bud on one another; the pear grows on
some hawthorns, but not well on an apple; some chestnuts will unite with
some kinds of oaks.
[Illustration: FIG. 72.
Lines show where to trim]
By using any of these methods you can succeed in getting with certainty
the kind of tree that you desire.
[Illustration: BOTH BUSY STORING APPLES]
SECTION XXIV. PLANTING AND PRUNING
The apple tree that you grafted should be set out in the spring. Dig a
hole three or four feet in diameter where you wish the tree to grow.
Place the tree in the hole and be very careful to preserve all the fine
roots. Spread the roots out fully, water them, and pack fine, rich soil
firmly about them. Place stakes about the young tree to protect it from
injury. If the spot selected is in a windy location, incline the tree
slightly toward the prevailing wind.
[Illustration: FIG. 73.
Present shape comes from pruning]
[Illustration: FIG. 74.
Correct shape]
You must prune the tree as it grows. The object of pruning is to give
the tree proper shape and to promote fruit-bearing. If the bud at the
end of the main shoot grows, you will have a tall, cone-shaped tree. If,
however, the end of the young tree be cut or "headed back" to the lines
shown in Fig. 72, the buds below this point will be forced to grow and
make a tree like that shown in Fig. 73. The proper height of heading for
different fruits varies. For the apple tree a height of two or three
feet is best.
Cutting an end bud of a shoot or branch always sends the nourishment and
growth into the side buds. Trimming or pinching off the side buds throws
the growth into the end bud. You can therefore cause your tree to take
almost any shape you desire. The difference between the trees shown in
Figs. 73 and 74 is entirely the result of pruning. Fig. 74 illustrates
in general a correctly shaped tree. It is evenly balanced, admits light
freely, and yet has enough foliage to prevent sun-scald. Figs. 75 and 76
show the effect of wisely thinning the branches.
[Illustration: FIG. 75.
Unthinned]
[Illustration: FIG. 76.
Properly thinned]
The best time to prune is either in the winter or before the buds start
in the spring. Winter pruning tends to favor wood-production, while
summer pruning lessens wood-production and induces fruitage.
Each particular kind of fruit requires special pruning; for example, the
peach should be made to assume the shape illustrated in Fig. 77. This is
done by successive trimmings, following the plan illustrated in Figs.
71, 78, 79. You will gain several advantages from these trimmings.
First, nourishment will be forced into the peach bud that you set on
your stock. This will secure a vigorous growth of the scion. By a second
trimming take off the "heel" (Fig. 78, _h_) close to the tree, and thus
prevent decay at this point. One year after budding you should reduce
the tree to a "whip," as in Fig. 79, by trimming at the dotted line in
Fig. 78. This establishes the "head" of the tree, which in the case of
the peach should be very low,--about sixteen inches from the ground,--in
order that a low foliage may lessen the danger of sun-scald to the main
trunk.
[Illustration: FIG. 77. THE CUSTOMARY WAY OF PRUNING A PEACH]
[Illustration: FIG. 78. TWO-YEAR-OLD TREE
Cut off heel, _h_]
In pruning never leave a stump such as is shown in Fig. 78, _h_. Such a
stump, having no source of nourishment, will heal very slowly and with
great danger of decay. If this heel is cleanly cut on the line _ch_
(Fig. 78), the wound will heal rapidly and with little danger of decay.
Leaving such a stump endangers the soundness of the whole tree. Fig. 80
shows the results of good and poor pruning on a large tree. When large
limbs are removed it is best to paint the cut surface. The paint will
ward off fungous disease and thus keep the tree from rotting where it
was cut.
Pruning that leaves large limbs branching, as in Fig. 74, _a_, is not to
be recommended, since the limbs when loaded with fruit or when beaten by
heavy winds are liable to break. Decay is apt to set in at the point of
breakage. The entrance of decay-fungi through some such wound or through
a tiny crevice at such a crotch is the beginning of the end of many a
fruitful tree.
[Illustration: FIG. 79. THREE-YEAR-OLD TREE CUT BACK]
Sometimes a tree will go too much to wood and too little to fruit. This
often happens in rich soil and may be remedied by another kind of
pruning known as _root-pruning_. This consists in cutting off a few of
the roots in order to limit the food supply of the plant. You ought to
learn more about root-pruning, however, before you attempt it.
[Illustration: FIG. 80.
Refuses to Heal--Heals promptly]
How is a peach tree made? First, the blossom appears. Then pollination
and fertilization occur. The fruit ripens. The pit, or seed, is saved.
In the spring of the next year the seed is planted. The young tree,
known as the stock, comes up quickly. In August of that year a bud of
the variety which is wanted is inserted in the little stock, near the
ground. One year later, in the spring, the stock is cut off just above
the bud. The bud throws out a shoot, which grows to a height of about
six feet, and in the fall this little peach tree is sold as a
one-year-old tree. However, as is seen, the root is two years old.
[Illustration: FIG. 81. READY TO BEAR]
How is an apple tree made? The seeds are saved in the fall of one year
and planted the following year. The seedlings of the apple do not grow
so rapidly as those of the peach. At the end of the year they are taken
up and sorted, and in the following spring they are planted. In July or
August they are budded. In the spring of the next year the stock is cut
off above the bud, and the bud-shoot grows three or four feet. One year
later the shoot branches and the top begins to form; and in the fall of
the following year the tree may be sold as a two-year-old, although most
persons prefer to buy it a year later as a three-year-old. In some parts
of the country, particularly in the West, the little seedling is grafted
in the second winter, in a grafting room, and the young grafts are set
in the nursery row in the spring to complete their growth.
The planting in the orchard of the young peach and the young apple tree
is done in practically the same way. After the hole for the tree has
been dug and after proper soil has been provided, the roots should be
spread and the soil carefully packed around them.
=EXERCISE=
Do you know any trees in your neighborhood that bear both wild and
budded or grafted fruit? What are the chief varieties of apples
grown in your neighborhood? grapes? currants? plums? cherries?
figs? What is a good apple tree worth? Is there any land near by
that could support a tree and is not now doing so? Examine several
orchards and see whether the trees have the proper shape. Do you
see any evidence of poor pruning? Do you find any heels? Can you
see any place where heels have resulted in rotten or hollow trees?
How could you have prevented this? Has the removal of branches ever
resulted in serious decay? How is this to be prevented?
If your home is not well stocked with all the principal kinds of
fruit, do you not want to propagate and attend to some of each
kind? You will be surprised to find how quickly trees will bear and
how soon you will be eating fruit from your own planting. Growing
your own trees will make you feel proud of your skill.
CHAPTER V
HORTICULTURE
SECTION XXV. MARKET-GARDENING
The word _horticulture_ is one of those broad words under which much is
grouped. It includes the cultivation of orchard fruits, such as apples
and plums; of small fruits, such as strawberries and raspberries; of
garden vegetables for the table; of flowers of all sorts, including
shrubbery and ornamental trees and their arrangement into beautiful
landscape effects around our homes. Horticulture then is a name for an
art that is both far-reaching and important.
The word _gardening_ is generally given to that part of horticulture
which has for its chief aim the raising of vegetables for our tables.
Flower-gardening, or the cultivation of plants valued for their bloom in
making ornamental beds and borders and furnishing flowers for the
decoration of the home, is generally called _floriculture_.
Landscape-gardening is the art of so arranging flower-beds, grass,
shrubbery, and trees as to produce pleasing effects in the grounds
surrounding our homes and in great public parks and pleasure grounds.
Landscape-gardening, like architecture, has developed intoll as the
artist makes them on canvas, but uses natural objects in his pictures
instead of paint and canvas.
=Market-Gardening.= Formerly market-gardening was done on small tracts
of land in the immediate vicinity of large cities, where supplies of
stable manure could be used from the city stables. But with the great
increase in the population of the cities, these small areas could no
longer supply the demand, and the introduction of commercial fertilizers
and the building of railroads enabled gardeners at great distances from
city markets to grow and ship their products. Hence the markets, even in
winter, are now supplied with fresh vegetables from regions where there
is no frost. Then, as spring opens, fruits and vegetables are shipped
from more temperate regions. Later vegetables and fruits come from the
sections nearer the great cities. This gradual nearing of the supply
fields continues until the gardens near the cities can furnish what is
needed.
[Illustration: FIG. 82. STRAWBERRY-GROWING IS AN ART]
The market-gardeners around the great Northern cities, finding that
winter products were coming from the South and from warmer regions,
began to build hothouses and by means of steam and hot-water pipes to
make warm climates in these glass houses. Many acres of land in the
colder sections of the country are covered with heated glass houses, and
in them during the winter are produced fine crops of tomatoes, lettuce,
radishes, cauliflowers, eggplants, and other vegetables. The degree of
perfection which these attain in spite of having such artificial
culture, and their freshness as compared to the products brought from a
great distance, have made winter gardening under glass a very profitable
business. But it is a business that calls for the highest skill and the
closest attention.
[Illustration: FIG. 83. SETTING PLANTS IN A COLD-FRAME]
No garden, even for home use, is complete without some glass sashes, and
the garden will be all the more successful if there is a small heated
greenhouse for starting plants that are afterwards to be set in the
garden.
=Hotbeds.= If there is no greenhouse, a hotbed is an important help in
the garden. The bed is made by digging a pit two feet deep, seven feet
wide, and as long as necessary.
The material for the hotbed is fresh horse manure mixed with leaves.
This is thrown into a heap to heat. As soon as steam is seen coming from
the heap the manure is turned over and piled again so that the outer
part is thrown inside. When the whole is uniformly heated and has been
turned two or three times, it is packed firmly into the pit already dug.
A frame six feet wide, twelve inches high on the north side and eight
inches on the south side and as long as the bed is to be, is now made of
plank. This is set upon the heated manure, thus leaving six inches on
each side outside the frame. More manure is then banked all around it,
and three or four inches of fine light and rich soil are placed inside
the frame.
[Illustration: FIG. 84. THE GLADIOLUS]
The frame is then covered with hotbed sashes six feet long and three
feet wide. These slide up and down on strips of wood let into the sides
of the frame. A thermometer is stuck into the soil and closely watched,
for there will be too much heat at first for sowing seed. When the heat
in the early morning is about 85 deg., seeds may be sowed. The hotbed is
used for starting tomato plants, eggplants, cabbage plants, and other
vegetables that cannot stand exposure. It should be made about eight or
ten weeks before the tender plants can be set out in the locality. In
the South and Southwest it should be started earlier than in the North.
For growing the best tomato plants, and for such hardy plants as lettuce
and cabbage, it will be better to have cold-frames in addition to the
hotbed; these need not be more than two or three sashes.
=Cold-Frames.= A cold-frame is like the frame used for a hotbed, but it
is placed on well-manured soil in a sheltered spot. It is covered with
the same kind of sashes and is used for hardening the plants sowed in
the hotbed. The frame must be well banked with earth on the outside, and
the glass must be covered on cold nights with straw, mats, or old
carpets to keep out frost.
[Illustration: FIG. 85. FRAME TO CARRY THE SASH OF A HOTBED OR COLD-FRAME]
=Care of Hotbed and Cold-Frame.= If the sun be allowed to shine brightly
on the glass of a cold-frame or hotbed, it will soon raise the
temperature in the hotbed to a point that will destroy the plants. It is
necessary, then, to pay close attention to the bed and, when the sun
shines, to slip the sashes down or raise them and place a block under
the upper end to allow the steam to pass off. The cold-frame also must
be aired when the sun shines, and the sashes must be gradually slipped
down in mild weather. Finally, they may be removed entirely on sunshiny
days, so as to accustom the plants to the open air, but they must be
replaced at night. For a while before setting the plants in the open
gardens, leave the sashes off night and day.
[Illustration: FIG. 86. GREENHOUSE AND COLD-FRAMES]
While the hotbed may be used for starting plants, it is much better and
more convenient to have a little greenhouse with fire heat for this
purpose. A little house with but four sashes on each side will be enough
to start a great many plants, and will also give room for some flowers
in pots. With such a house a student can learn to manage a more
extensive structure if he gives close attention to airing, watering, and
keeping out insects.
=Sowing.= The time for sowing the different kinds of seeds is an
important matter. Seeds vary greatly in their requirements. All need
three conditions--a proper degree of heat, moisture, and air. Some
seeds, like English peas, parsnips, beets, and radishes, will germinate
and grow when the soil is still cool in the early spring, and peas will
stand quite a frost after they are up. Therefore we plant English peas
as early as the ground can be worked.
But if we should plant seeds like corn, string (or snap) beans,
squashes, and other tender plants before the ground is warm enough, they
would decay.
Seeds cannot germinate in soil that is perfectly dry, for there must be
moisture to swell them and to start growth. The oxygen of the air is
also necessary, and if seeds are buried so deeply that the air cannot
reach them, they will not grow, even if they are warm and moist.
[Illustration: FIG. 87. GATHERING AND SHIPPING CELERY]
The depth of planting must vary with the character and size of the seed.
English peas may be covered six inches deep and will be all the better
for such covering, but if corn be covered so deep, it hardly gets above
the ground. In planting small seeds like those of the radish, cabbage,
turnip, lettuce, etc., a good rule is to cover them three times the
thickness of the seed.
In sowing seeds when the ground is rather dry, it is a good plan, after
covering them, to tramp on the row so as to press the soil closely to
the seeds and to help it to retain moisture for germination, but do not
pack the soil if it is damp.
In spring never dig or plow the garden while it is still wet, but always
wait until the soil is dry enough to crumble freely.
=What Crops to grow.= The crops to be raised will of course depend upon
each gardener's climate, surroundings, and markets. Sometimes it may pay
a grower, if his soil and climate are particularly suited to one crop,
to expend most of his time and energy on this crop; for example, in some
sections of New York, on potatoes; in parts of Michigan, on celery; in
Georgia, on watermelons; in western North Carolina, on cabbage. If
circumstances allow this sort of gardening, it has many advantages, for
of course it is much easier to acquire skill in growing one crop than in
growing many.
[Illustration: FIG. 88. A LARGE YIELD OF CABBAGES]
On the other hand, it often happens that a gardener's situation requires
him to grow most of the crops known to gardening. Each gardener then
must be guided in his selection of crops by his surroundings.
=Care of Crops.= The gardener who wishes to attain the greatest success
in his art must do four things:
First, he must make his land rich and keep it rich. Much of his success
depends on getting his crops on the market ahead of other growers. To do
this, his crops must grow rapidly, and crops grow rapidly only in rich
soil. Then, too, land conveniently situated for market-gardening is
nearly always costly. Hence the successful market-gardener must plan to
secure the largest possible yield from as small an area as is
practicable. The largest yield can of course be secured from the richest
land.
Second, the gardener must cultivate his rich land most carefully and
economically. He crowds his land with products that must grow apace.
Therefore he, least of all growers, can afford to have any of his soil
go to feed weeds, to have his land wash, or to have his growing crops
suffer for lack of timely and wise cultivation. To cultivate his land
economically the gardener must use the best tools and machines and the
best methods of soil management.
Third, to get the best results he must grow perfect vegetables. To do
this, he must add to good tillage a knowledge of the common plant
diseases and of the ways of insects and bacterial pests; he must know
how and when to spray, how and when to treat his seed, how and when to
poison, how and when to trap his insect foes and to destroy their
hiding-places.
Fourth, not only must the gardener grow perfect vegetables, but he must
put them on the market in perfect condition and in attractive shape. Who
cares to buy wilted, bruised, spoiling vegetables? Gathering, bundling,
crating, and shipping are all to be watched carefully. Baskets should be
neat and attractive, crates clean and snug, barrels well packed and well
headed. Careful attention to all these details brings a rich return.
Among the gardener's important crops are the following:
=Asparagus.= This is a hardy plant. Its seed may be sowed either early
in the spring or late in the fall. The seeds should be planted in rows.
If the plants are well cultivated during the spring and summer, they
will make vigorous roots for transplanting in the autumn.
In the fall prepare a piece of land by breaking it unusually deep and by
manuring it heavily. After the land is thoroughly prepared, make in it
furrows for the asparagus roots. These furrows should be six inches deep
and three feet apart. Then remove the roots from the rows in which they
have been growing during the summer, and set them two feet apart in the
prepared furrows. Cover carefully at once.
[Illustration: FIG. 89. A CRATE OF ASPARAGUS]
In the following spring the young shoots must be well cultivated. In
order to economize space, beets or lettuce may be grown between the
asparagus rows during this first season. With the coming of cold weather
the asparagus must again be freely manured and all dead tops cut off.
Some plants will be ready for market the second spring. If the bed is
kept free from weeds and well manured, it will increase in
productiveness from year to year.
=Beans.= The most generally planted beans are those known as string, or
snap, beans. Of the many varieties, all are sensitive to cold and hence
must not be planted until frost is over.
Another widely grown kind of bean is the lima, or butter, bean. There
are two varieties of the lima bean. One is large and generally grows on
poles. This kind does best in the Northern states. The other is a small
bean and may be grown without poles. This kind is best suited to the
warmer climates of the Southern states.
=Cabbage.= In comparatively warm climates the first crop of cabbage is
generally grown in the following way. The seeds are sowed in beds in
September, and the plants grown from this sowing are in November
transplanted to ground laid off in sharp ridges. The young plants are
set on the south side of the ridges in order that they may be somewhat
protected from the cold of winter. As spring comes on, the ridge is
partly cut down at each working until the field is leveled, and
thereafter the cultivation should be level.
[Illustration: FIG. 90. CABBAGE READY FOR SHIPMENT]
Early cabbages need heavy applications of manure. In the spring, nitrate
of soda applied in the rows is very helpful.
Seeds for the crop following this early crop should be sowed in March.
Of course these seeds should be of a later variety than the first used.
The young plants should be transplanted as soon as they are large
enough. Early cabbages are set in rows three feet apart, the plants
eighteen inches apart in the row. As the later varieties grow larger
than the earlier ones, the plants should be set two feet apart in the
row.
In growing late fall and winter cabbage the time of sowing varies with
the climate. For the Northern and middle states, seeding should be done
during the last of March and in April. South of a line passing west from
Virginia it is hard to carry cabbages through the heat of summer and get
them to head in the fall. However, if the seeds are sowed about the
first of August in rich and moist soil and the plants set in the same
sort of soil in September, large heads can be secured for the December
market.
[Illustration: FIG. 91. CELERY TRIMMED, WASHED, AND BUNCHED]
=Celery.= In the extreme northern part of our country, celery seeds are
often sowed in a greenhouse or hotbed. This is done in order to secure
plants early enough for summer blanching. This plan, however, suits only
very cool climates.
In the middle states the seeds are usually sowed in a well-prepared bed
about April. The young plants are moved to other beds as soon as they
need room. Generally they are transplanted in July to rows prepared for
them. These should be four feet apart, and the plants should be set six
inches apart in the row. The celery bed should be carefully cultivated
during the summer. In the fall, hill the stalks up enough to keep them
erect. After the growing season is over dig them and set them in
trenches. The trenches should be as deep as the celery is tall, and
after the celery is put in them they should be covered with boards and
straw.
In the more southern states, celery is usually grown in beds. The beds
are generally made six feet wide, and rows a foot apart are run
crosswise. The plants are set six inches apart, in September, and the
whole bed is earthed up as the season advances. Finally, when winter
comes the beds are covered with leaves or straw to prevent the plants
from freezing. The celery is dug and bunched for market at any time
during the winter.
By means of cold-frames a profitable crop of spring celery may be
raised. Have the plants ready to go into the cold-frames late in October
or early in November. The soil in the frame should be made very deep.
The plants should make only a moderately rapid growth during the winter.
In the early spring they will grow rapidly and so crowd one another as
to blanch well. As celery grown in this way comes on the market at a
time when no other celery can be had, it commands a good price.
In climates as warm as that of Florida, beds of celery can be raised in
this way without the protection of cold-frames. A slight freeze does not
hurt celery, but a long-continued freezing spell will destroy it.
Some kinds of celery seem to turn white naturally. These are called
self-blanching kinds. Other kinds need to be banked with earth in order
to make the stalks whiten. This kind usually gives the best and crispest
stalks.
=Cucumbers and Cantaloupes.= Although cucumbers and cantaloupes are very
different plants, they are grown in precisely the same way. Some
gardeners plant them in hills. However, this is perhaps not the best
plan. It is better to lay the land off in furrows six feet apart. After
filling these with well-rotted stable manure, throw soil over them. Then
make the top flat and plant the seeds. After the plants are up thin them
out, leaving them a foot or more apart in the rows. Cultivate regularly
and carefully until the vines cover the entire ground.
It is a good plan to sow cowpeas at the last working of cantaloupes, in
order to furnish some shade for the melons. As both cucumbers and
cantaloupes are easily hurt by cold, they should not be planted until
the soil is warm and all danger of frost is past.
Cucumbers are always cut while they are green. They should never be
pulled from the vine, but should always be cut with a piece of the stem
attached. Cantaloupes should be gathered before they turn yellow and
should be ripened in the house.
[Illustration: FIG. 92. STRIPED CUCUMBER BEETLE AND LARVA
All magnified]
In some sections of the country the little striped cucumber-beetle
attacks the melons and cucumbers as soon as they come up. These beetles
are very active, and if their attacks are not prevented they will
destroy the tender plants. Bone dust and tobacco dust applied just as
the plants appear above the ground will prevent these attacks. This
treatment not only keeps off the beetle, but also helps the growth of
the plants.
=Eggplants.= Eggplants are so tender that they cannot be transplanted
like tomatoes to cold-frames and gradually hardened to stand the cold
spring air. These plants, started in a warm place, must be kept there
until the soil to which they are to be transplanted is well warmed by
the advance of spring. After the warm weather has fully set in,
transplant them to rich soil, setting them three feet apart each way.
This plant needs much manure. If large, perfect fruit is expected, the
ground can hardly be made too rich.
Eggplants are subject to the same bacterial blight that is so
destructive to tomatoes. The only way to prevent this disease is to
plant in ground not lately used for tomatoes or potatoes.
[Illustration: FIG. 93. AN ONION HARVEST]
=Onions.= The method of growing onions varies with the use to which it
is intended to put them. To make the early sorts, which are eaten green
in the spring, little onions called _sets_ are planted. These are grown
from seeds sowed late in the spring. The seeds are sowed thickly in rows
in rather poor land. The object of selecting poor land is that the
growth of the sets may be slow. When the sets have reached the size of
small marbles, they are ready for the fall planting.
In the South the sets may be planted in September. Plant them in rows in
rich and well-fertilized soil. They will be ready for market in March
or April. In the more northerly states the sets are to be planted as
early as possible in the spring.
To grow ripe onions the seeds must be sowed as early in the spring as
the ground can be worked. The plants are thinned to a stand of three
inches in the rows. As they grow, the soil is drawn away from them so
that the onions sit on top of the soil with only their roots in the
earth.
[Illustration: FIG. 94. HOTBED FOR STARTING TOMATO PLANTS]
As soon as the tops ripen pull the onions and let them lie in the sun
until the tops are dry. Then put them under shelter. As onions keep best
with their tops attached, do not remove these until it is time for
marketing.
=Peas.= The English pea is about the first vegetable of the season to be
planted. It may be planted as soon as the ground is in workable
condition. Peas are planted in rows, and it is a good plan to stretch
wire netting for them to climb on. However, where peas are extensively
cultivated they are allowed to fall on the ground.
There are many sorts of peas, differing both in quality and in time of
production. The first to be planted are the extra-early varieties. These
are not so fine as the later, wrinkled sorts, but the seeds are less apt
to rot in cold ground. Following these, some of the fine, wrinkled sorts
are to be planted in regular succession. Peas do not need much manure
and do best in a light, warm soil.
=Tomatoes.= There is no vegetable grown that is more widely used than
the tomato. Whether fresh or canned it is a staple article of food that
can be served in many ways.
By careful selection and breeding, the fruit of the tomato has in recent
years been much improved. There are now many varieties that produce
perfectly smooth and solid fruit, and the grower can hardly go amiss in
his selection of seeds if he bears his climate and his particular needs
in mind.
Early tomatoes are started in the greenhouse or in the hotbed about ten
weeks before the time for setting the plants in the open ground. They
are transplanted to cold-frames as soon as they are large enough to
handle. This is done to harden the plants and to give them room to grow
strong before the final transplanting.
In kitchen gardens tomatoes are planted in rows four feet apart with the
plants two feet apart in the rows. They are generally trained to stakes
with but one stalk to a stake. When there is plenty of space, however,
the plants are allowed to grow at will and to tumble on the ground. In
this way they bear large crops. During the winter the markets are
supplied with tomatoes either from tropical sections or from hothouses.
As those grown in the hothouses are superior in flavor to those shipped
from Florida and from the West Indies, and as they command good prices,
great quantities are grown in this way.
In the South the bacterial blight which attacks the plants of this
family is a serious drawback to tomato culture. The only way to escape
this disease is to avoid planting tomatoes on land in which eggplants,
tomatoes, or potatoes have been blighted. Lime spread around the plants
seems to prevent the blight for one season on some soils.
At the approach of frost in the fall, green tomatoes can easily be
preserved by wrapping them in paper. Gather them carefully and wrap each
separately. Pack them in boxes and store in a cellar that is close
enough to prevent the freezing of the fruit. A few days before the
tomatoes are wanted for the table unpack as many as are needed, remove
the paper, and allow them to ripen in a warm room.
Tomatoes require a rich soil. Scattering a small quantity of nitrate of
soda around their roots promotes rapid growth.
=Watermelons.= As watermelons need more room than can usually be spared
in a garden, they are commonly grown as a field crop.
A very light, sandy soil suits watermelons best. They can be grown on
very poor soil if a good supply of compost be placed in each hill. The
land for the melons should be laid off in about ten-foot checks; that
is, the furrows should cross one another at right angles about every ten
feet. A wide hole should be dug where the furrows cross, and into this
composted manure should be put.
The best manure for watermelons is a compost of stable manure and
wood-mold from the forest. Pile the manure and wood-mold in alternate
layers for some time before the planting season. During the winter cut
through the pile several times until the two are thoroughly mixed and
finely pulverized. Be sure to keep the compost heap under shelter.
Compost will lose in value if it is exposed to rains.
At planting-time, put two or three shovelfuls of this compost into each
of the prepared holes, and over the top of the manure scatter a handful
of any high-grade complete fertilizer. Then cover fertilizer and manure
with soil, and plant the seeds in this soil. In cultivating, plow both
ways of the checked rows and throw the earth toward the plants.
Some growers pinch off the vines when they have grown about three feet
long. This is done to make them branch more freely, but the pinching is
not necessary.
A serious disease, the watermelon wilt, is rapidly spreading through
melon-growing sections. This disease is caused by germs in the soil, and
the germs are hard to kill. If the wilt should appear in your
neighborhood, do not allow any stable manure to be used on your melon
land, for the germs are easily scattered by means of stable manure. The
germs also cling to the seeds of diseased melons, and these seeds bear
the disease to other fields. If you treat melon seeds as you are
directed on page 135 to treat oat seeds, the germs on the seeds will be
destroyed. By crossing the watermelon on the citron melon, a watermelon
that is resistant to wilt has recently been developed and successfully
grown in soils in which wilt is present. The new melon, inferior in
flavor at first, is being improved from season to season and bids fair
to rival other melons in flavor.
[Illustration: FIG. 95. DEWBERRIES]
SECTION XXVI. FLOWER GARDENING
The comforts and joys of life depend largely upon small things. Of these
small things perhaps none holds a position of greater importance in
country life than the adornment of the home, indoors and outdoors, with
flowers tastefully arranged. Their selection and planting furnish
pleasant recreation; their care is a pleasing employment; and each
little plant, as it sprouts and grows and develops, may become as much a
pet as creatures of the sister animal kingdom. A beautiful, well-kept
yard adds greatly to the pleasure and attractiveness of a country home.
If a beautiful yard and home give joy to the mere passer-by, how much
more must their beauty appeal to the owners. The decorating of the home
shows ambition, pride, and energy--important elements in a successful
life.
[Illustration: FIG. 96. AN EASY WAY TO BEAUTIFY THE HOME]
Plant trees and shrubs in your yard and border your masses of shrubbery
with flower-beds. Do not disfigure a lawn by placing a bed of flowers in
it. Use the flowers rather to decorate the shrubbery, and for borders
along walks, and in the corners near steps, or against foundations.
If you wish to raise flowers for the sake of flowers, not as
decorations, make the flower-beds in the back yard or at the side of the
house.
[Illustration: FIG. 97. A BACK YARD TO REFINE THE CHILDREN OF THE
FAMILY]
Plants may be grown from seeds or from bulbs or from cuttings. The
rooting of cuttings is an interesting task to all who are fond of
flowers. Those who have no greenhouse and who wish to root cuttings of
geraniums, roses, and other plants may do so in the following way. Take
a shallow pan, an old-fashioned milk pan for instance, fill it nearly
full of clean sand, and then wet the sand thoroughly. Stick the cuttings
thickly into this wet sand, set the pan in a warm, sunny window, and
keep the sand in the same water-soaked condition. Most cuttings will
root well in a few weeks and may then be set into small flower-pots.
Cuttings of tea roses should have two or three joints and be taken from
a stem that has just made a flower. Allow one of the rose leaves to
remain at the top of the cutting. Stick this cutting into the sand and
it will root in about four weeks. Cuttings of Cape jasmine may be rooted
in the same way. Some geraniums, the rose geranium for example, may be
grown from cuttings of the roots.
[Illustration: FIG. 98. REPOTTING]
Bulbs are simply the lower ends of the leaves of a plant wrapped tightly
around one another and inclosing the bud that makes the future
flower-stalk. The hyacinth, the narcissus, and the common garden onion
are examples of bulbous plants. The flat part at the bottom of the bulb
is the stem of the plant reduced to a flat disk, and between each two
adjacent leaves on this flat stem there is a bud, just as above-ground
there is a bud at the base of a leaf. These buds on the stem of the bulb
rarely grow, however, unless forced to do so artificially. The number
of bulbs may be greatly increased by making these buds grow and form
other bulbs. In increasing hyacinths the matured bulbs are dug in the
spring, and the under part of the flat stem is carefully scraped away to
expose the base of the buds. The bulbs are then put in heaps and covered
with sand. In a few weeks each bud has formed a little bulb. The
gardener plants the whole together to grow one season, after which the
little bulbs are separated and grown into full-sized bulbs for sale.
Other bulbs, like the narcissus or the daffodil, form new bulbs that
separate without being scraped.
[Illustration: FIG. 99. A CLEMATIS]
There are some other plants which have underground parts that are
commonly called bulbs but which are not bulbs at all; for example, the
gladiolus and the caladium, or elephant's ear. Their underground parts
are bulblike in shape, but are really solid flattened stems with eyes
like the underground stem of the Irish potato. These parts are called
_corms_. They may be cut into pieces like the potato and each part will
grow.
The dahlia makes a mass of roots that look greatly like sweet potatoes,
but there are no eyes on them as there are on the sweet potato. The only
eyes are on the base of the stem to which they are joined. They may be
sprouted like sweet potatoes and then soft cuttings made of the green
shoots, after which they may be rooted in the greenhouse and later
planted in pots.
There are many perennial plants that will bloom the first season when
grown from the seed, though such seedlings are seldom so good as the
plants from which they came. They are generally used to originate new
varieties. Seeds of the dahlia, for instance, can be sowed in a box in a
warm room in early March, potted as soon as the plants are large enough
to handle, and finally planted in the garden when the weather is warm.
They will bloom nearly as soon as plants grown by dividing the roots or
from cuttings.
[Illustration: FIG. 100. OUTDOOR-GROWN CHRYSANTHEMUMS]
In growing annual plants from seed, there is little difficulty if the
grower has a greenhouse or a hotbed with a glass sash. Even without
these the plants may be grown in shallow boxes in a warm room. The best
boxes are about four inches deep with bottoms made of slats nailed a
quarter of an inch apart to give proper drainage. Some moss is laid over
the bottom to prevent the soil from sifting through. The boxes should
then be filled with light, rich soil. Fine black forest mold, thoroughly
mixed with one fourth its bulk of well-rotted manure, makes the best
soil for filling the seed-boxes. If this soil be placed in an oven and
heated very hot, the heat will destroy many weeds that would otherwise
give trouble. After the soil is put in the boxes it should be well
packed by pressing it with a flat wooden block. Sow the seeds in
straight rows, and at the ends of the rows put little wooden labels with
the names of the flowers on them.
[Illustration: FIG. 101. THE CARNATION (ELDORADO)]
Seeds sowed in the same box should be of the same general size in order
that they may be properly covered, for seeds need to be covered
according to their size. After sowing the seed, sift the fine soil over
the surface of the box. The best soil for covering small seeds is made
by rubbing dry moss and leaf-mold through a sieve together. This makes a
light cover that will not bake and will retain moisture. After covering
the seeds, press the soil firm and smooth with a wooden block. Now
sprinkle the covering soil lightly with a watering-pot until it is
fairly moistened. Lay some panes of glass over the box to retain the
moisture, and avoid further watering until moisture becomes absolutely
necessary. Too much watering makes the soil too compact and rots the
seed.
As soon as the seedlings have made a second pair of leaves, take them up
with the point of a knife and transplant them into other boxes filled in
the same way. They should be set two inches apart so as to give them
room to grow strong. They may be transplanted from the boxes to the
flower-garden by taking an old knife-blade and cutting the earth into
squares, and then lifting the entire square with the plant and setting
it where it is wanted.
There are many flower-seeds which are so small that they must not be
covered at all. In this class we find begonias, petunias, and Chinese
primroses. To sow these prepare boxes as for the other seeds, and press
the earth smooth. Then scatter some fine, dry moss thinly over the
surface of the soil. Sprinkle this with water until it is well
moistened, and at once scatter the seeds thinly over the surface and
cover the boxes with panes of glass until the seeds germinate.
Transplant as soon as the young plants can be lifted out separately on
the blade of a penknife.
[Illustration: FIG. 102. THE POET'S NARCISSUS]
Many kinds of flower-seeds may be sowed directly in the open ground
where they are to remain. The sweet pea is one of the most popular
flowers grown in this way. The seeds should be sowed rather thickly in
rows and covered fully four inches deep. The sowing should be varied in
time according to the climate. From North Carolina southward, sweet peas
may be sowed in the fall or in January, as they are very hardy and
should be forced to bloom before the weather becomes hot. Late spring
sowing will not give fine flowers in the South. From North Carolina
northward the seeds should be sowed just as early in the spring as the
ground can be easily worked. When the plants appear, stakes should be
set along the rows and a strip of woven-wire fence stretched for the
plants to climb on. Morning-glory seeds are also sowed where they are to
grow. The seeds of the moonflower are large and hard and will fail to
grow unless they are slightly cut. To start their growth make a slight
cut just through the hard outer coat of the seed so as to expose the
white inside. In this way they will grow very readily. The seeds of the
canna, or Indian-shot plant, are treated in a similar way to start them
growing.
[Illustration: FIG. 103. A CYCLAMEN]
[Illustration: FIG. 104. A MODERN SWEET PEA]
The canna makes large fleshy roots which in the North are taken up,
covered with damp moss, and stored under the benches of the greenhouse
or in a cellar. If allowed to get too dry, they will wither. From
central North Carolina south it is best to cover them up thickly with
dead leaves and let them stay in the ground where they grew. In the
early spring take them up and divide for replanting.
[Illustration: FIG. 105. DAHLIAS]
Perennial plants, such as our flowering shrubs, are grown from cuttings
of the ripe wood after the leaves have fallen in autumn. From North
Carolina southward these cuttings should be set in rows in the fall.
Cuttings ten inches long are set so that the tops are just even with the
ground. A light cover of pine leaves will prevent damage from frost.
Farther north the cuttings should be tied in bundles and well buried in
the ground with earth heaped over them. In the spring set them in rows
for rooting. In the South all the hardy hybrid perpetual roses can be
grown in this way, and in any section the cuttings of most of the
spring-flowering shrubs will grow in the same manner. The Japanese
quince, which makes such a show of its scarlet flowers in early spring,
can be best grown from three-inch cuttings made of the roots and planted
in rows in the fall.
[Illustration: FIG. 106. FOUR-O'CLOCKS SET IN A GOOD PLACE]
Many of our ornamental evergreen trees, such as the arbor vitae, can be
grown in the spring from seeds sowed in a frame. Cotton cloth should be
stretched over the trees while they are young, to prevent the sun from
scorching them. When a year old they may be set in nursery rows to
develop until they are large enough to plant. Arbor vitae may also be
grown from cuttings made by setting young tips in boxes of sand in the
fall and keeping them warm and moist through the winter. Most of them
will be rooted by spring.
The kinds of flowers that you can grow are almost countless. You can
hardly make a mistake in selecting, as all are interesting. Start this
year with a few and gradually increase the number under your care year
by year, and aim always to make your plants the choicest of their kind.
Of annuals there are over four hundred kinds cultivated. You may select
from the following list: phlox, petunias, China asters, California
poppies, sweet peas, pinks, double and single sunflowers, hibiscus,
candytuft, balsams, morning-glories, stocks, nasturtiums, verbenas,
mignonette.
[Illustration: FIG. 107. A WINDOW BOX]
Of perennials select bleeding-hearts, pinks, bluebells, hollyhocks,
perennial phlox, perennial hibiscus, wild asters, and goldenrods. From
bulbs choose crocus, tulip, daffodil, narcissus, lily of the valley, and
lily.
Some climbers are cobaea, honeysuckle, Virginia creeper, English ivy,
Boston ivy, cypress vine, hyacinth bean, climbing nasturtiums, and
roses.
To make your plants do best, cultivate them carefully. Allow no weeds to
grow among them and do not let the surface of the soil dry into a hard
crust. Beware, however, of stirring the soil too deep. Loosening the
soil about the roots interrupts the feeding of the plant and does harm.
Climbing plants may be trained to advantage on low woven-wire fences.
These are especially serviceable for sweet peas and climbing
nasturtiums. Do not let the plants go to seed, since seeding is a heavy
drain on nourishment. Moreover, the plant has served its end when it
seeds and is ready then to stop blossoming. You should therefore pick
off the old flowers to prevent their developing seeds. This will cause
many plants which would otherwise soon stop blossoming to continue
bearing flowers for a longer period.
[Illustration: FIG. 108. A WINDOW-GARDEN]
=Window-Gardening.= Growing plants indoors in the window possesses many
of the attractions of outdoor flower-gardening, and is a means of
beautifying the room at very small expense. Especially do window-gardens
give delight during the barren winter time. They are a source of culture
and pleasure to thousands who cannot afford extended and expensive
ornamentation.
The window-garden may vary in size from an eggshell holding a minute
plant to boxes filling all the available space about the window. The
soil may be in pots for individual plants or groups of plants or in
boxes for collections of plants. You may raise your flowers inside of
the window on shelves or stands, or you may have a set of shelves built
outside of the window and inclosed in glazed sashes. The illustration on
page 119 gives an idea of such an external window-garden.
[Illustration: FIG. 109. AN INSIDE WINDOW BOX IN ITS FULL GLORY]
The soil must be rich and loose. The best contains some undecayed
organic matter such as leaf-mold or partly decayed sods and some sand.
Raise your plants from bulbs, cuttings, or seed, just as in outdoor
gardens. Some plants do better in cool rooms, others in a warmer
temperature.
[Illustration: FIG. 110. MAKING THE OUTSIDE OF A WINDOW BLOOM]
If the temperature ranges from 35 deg. to 70 deg., averaging about 55 deg., azaleas,
daisies, carnations, candytuft, alyssum, dusty miller, chrysanthemums,
cinerarias, camellias, daphnes, geraniums, petunias, violets, primroses,
and verbenas make especially good growths.
[Illustration: A BEAUTIFUL WINDOW FLOWER]
If the temperature is from 50 deg. to 90 deg., averaging 70 deg., try abutilon,
begonia, bouvardia, caladium, canna, Cape jasmine, coleus, fuchsia,
gloxinia, heliotrope, lantana, lobelia, roses, and smilax.
If your box or window is shaded a good part of the time, raise begonias,
camellias, ferns, and Asparagus Sprengeri.
[Illustration: FIG. 111. FERNS FOR BOTH INDOORS AND OUTDOORS]
When the soil is dry, water it; then apply no more water until it again
becomes dry. Beware of too much water. The plants should be washed
occasionally with soapsuds and then rinsed. If red spiders are present,
sponge them off with water as hot as can be borne comfortably by the
hand. Newspapers afford a good means of keeping off the cold.
CHAPTER VI
THE DISEASES OF PLANTS
SECTION XXVII. THE CAUSE AND NATURE OF PLANT DISEASE
Plants have diseases just as animals do; not the same diseases, to be
sure, but just as serious for the plant. Some of them are so dangerous
that they kill the plant; others partly or wholly destroy its usefulness
or its beauty. Some diseases are found oftenest on very young plants,
others prey on the middle-aged tree, while still others attack merely
the fruit. Whenever a farmer or fruit-grower has disease on his plants,
he is sure to lose much profit.
You have all seen rotten fruit. This is diseased fruit. Fruit rot is a
plant disease. It costs farmers millions of dollars annually. A
fruit-grower recently lost sixty carloads of peaches in a single year
through rot which could have been largely prevented if he had known how.
Many of the yellowish or discolored spots on leaves are the result of
disease, as is also the smut of wheat, corn, and oats, the blight of the
pear, and the wilt of cotton. Many of these diseases are contagious, or,
as we often hear said of measles, "catching." This is true, among
others, of the apple and peach rots. A healthy apple can catch this
disease from a sick apple. You often see evidence of this in the apple
bin. So, too, many of the diseases found in the field or garden are
contagious.
Sometimes when the skin of a rotten apple has been broken you will find
in the broken place a blue mold. It was this that caused the apple to
decay. This mold is a living plant; very small, certainly, but
nevertheless a plant. Let us learn a little about molds, in order that
we may better understand our apple and potato rots, as well as other
plant diseases.
If you cut a lemon and let it stand for a day or two, there will
probably appear a blue mold like that you have seen on the surface of
canned fruit. Bread also sometimes has this blue mold; at other times
bread has a black mold, and yet again a pink or a yellow mold.
These and all other molds are tiny living plants. Instead of seeds they
produce many very small bodies that serve the purpose of seeds and
reproduce the mold. These are called _spores_. Fig. 112 shows how they
are borne on the parent plant.
[Illustration: FIG. 112. TANGLED THREADS OF BLUE MOLD
The single stalk on the left shows how spores are borne]
It is also of great importance to decide whether by keeping the spores
away we may prevent mold. Possibly this experiment will help us. Moisten
a piece of bread, then dip a match or a pin into the blue mold on a
lemon, and draw the match across the moist bread. You will thus plant
the spores in a row, though they are so small that perhaps you may not
see any of them. Place the bread in a damp place for a few days and
watch it. Does the mold grow where you planted it? Does it grow
elsewhere? This experiment should prove to you that molds are living
things and can be planted. If you find spots elsewhere, you must bear in
mind that these spores are very small and light and that some of them
were probably blown about when you made your sowing. When you touch the
moldy portion of a dry lemon, you see a cloud of dust rise. This dust is
made of millions of spores.
[Illustration: FIG. 113. MAGNIFIED ROSE MILDEW]
If you plant many other kinds of mold you will find that the molds come
true to the kind that is planted; that like produces like even among
molds.
[Illustration: FIG. 114. A MILDEWED ROSE]
You can prove, also, that the mold is caused only by other mold. To do
this, put some wet bread in a wide-mouthed bottle and plug the mouth of
the bottle with cotton. Kill all the spores that may be in this bottle
by steaming it an hour in a cooking-steamer. This bread will not mold
until you allow live mold from the outside to enter. If, however, at any
time you open the bottle and allow spores to enter, or if you plant
spores therein, and if there be moisture enough, mold will immediately
set in.
[Illustration: FIG. 115. A HIGHLY MAGNIFIED SECTION OF DISEASED PEAR LEAF
Showing how spores are borne]
The little plants which make up these molds are called _fungi_. Some
fungi, such as the toadstools, puffballs, and devil's snuff-box, are
quite large; others, namely the molds, are very small; and others are
even smaller than the molds. Fungi never have the green color of
ordinary plants, always reproduce by spores, and feed on living matter
or matter that was once alive. Puffballs, for example, are found on
rotting wood or dead twigs or roots. Some fungi grow on living plants,
and these produce plant disease by taking their nourishment from the
plant on which they grow; the latter plant is called the _host_.
The same blue mold that grows on bread often attacks apples that have
been slightly bruised; it cannot pierce healthy apple skin. You can
plant the mold in the bruised apple just as you did on bread and watch
its rapid spread through the apple. You learn from this the need of
preventing bruised or decayed apples from coming in contact with healthy
fruit.
[Illustration: FIG. 116. SPORES OF THE PEAR SCAB
The spores are borne on stalks]
Just as the fungus studied above lives in the apple or bread, so other
varieties live on leaves, bark, etc. Fig. 113 represents the surface of
a mildewed rose leaf greatly magnified. This mildew is a fungus. You can
see its creeping stems, its upright stalk, and numerous spores ready to
fall off and spread the disease with the first breath of wind. You must
remember that this figure is greatly magnified, and that the whole
portion shown in the figure is only about one tenth of an inch across.
Fig. 114 shows the general appearance of a twig affected by this
disease.
Mildew on the rose or on any other plant may be killed by spraying the
leaves with a solution of liver of sulphur; to make this solution, use
one ounce of the liver of sulphur to two gallons of water.
The fungus that causes the pear-leaf spots has its spores in little pits
(Fig. 115). The spores of some fungi also grow on stalks, as shown in
Fig. 116. This figure represents an enlarged view of the pear scab,
which causes so much destruction.
You see, then, that fungi are living plants that grow at the expense of
other plants and cause disease. Now if you can cover the leaf with a
poison that will kill the spore when it comes, you can prevent the
disease. One such poison is the Bordeaux (_bor-do_') mixture, which
has proved of great value to farmers.
Since the fungus in most cases lives within the leaves, the poison on
the outside does no good after the fungus is established. The treatment
can be used only to _prevent_ attack, not to cure, except in the case of
a few mildews that live on the outside of the leaf, as does the rose
mildew.
=EXERCISE=
Why do things mold more readily in damp places? Do you now
understand why fruit is heated before it is canned? Try to grow
several kinds of mold. Do you know any fungi which may be eaten?
Transfer disease from a rotten apple to a healthy one and note the
rapidity of decay. How many really healthy leaves can you find on a
strawberry plant? Do you find any spots with reddish borders and
white centers? Do you know that this is a serious disease of the
strawberry? What damage does fruit mold do to peaches, plums, or
strawberries?
Write to your experiment station for bulletins on plant diseases
and methods for making and using spraying mixtures.
SECTION XXVIII. YEAST AND BACTERIA
Can you imagine a plant so small that it would take one hundred plants
lying side by side to equal the thickness of a sheet of writing-paper?
There are plants that are so small. Moreover, these same plants are of
the utmost importance to man. Some of them do him great injury, while
others aid him very much.
You will see their importance when you are told that certain of them in
their habits of life cause great change in the substances in which they
live. For example, when living in a sugary substance they change the
sugar into a gas and an alcohol. Do you remember the bright bubbles of
gas you have seen rising in sweet cider or in wine as it soured? These
bubbles are caused by one of these small plants--the yeast plant. As the
yeast plant grows in the sweet fruit juice, alcohol is made and a gas is
given off at the same time, and this gas makes the bubbles.
[Illustration: FIG. 117. YEAST PLANTS
_A_, a single plant; _B_, group of two budding cells; _C_, group of
several cells]
Later, other kinds of plants equally small will grow and change the
alcohol into an acid which you will recognize as vinegar by its sour
taste and peculiar odor. Thus vinegar is made by the action of two
different kinds of little living plants in the cider. That these are
living beings you can prove by heating the cider and keeping it tightly
sealed so that nothing can enter it. You will find that because the
living germs have been killed by the heat, the cider will not ferment or
sour as it did before. The germs could of course be killed by poisons,
but then the cider would be unfit for use. It is this same little yeast
plant that causes bread to rise.
When you see any decaying matter you may know that in it minute plants
much like the yeast plant are at work. Since decay is due to them, we
take advantage of the fact that they cannot grow in strong brine or
smoke; and we prepare meat for keeping by salting it or by smoking it or
by both of these methods.
You see that some of the yeast plants and _bacteria_, as many of these
forms are called, are very friendly to us, while others do us great
harm.
Some bacteria grow within the bodies of men and other animals or in
plants. When they do so they may produce disease. Typhoid fever,
diphtheria, consumption, and many other serious diseases are caused by
bacteria. Fig. 118, _e_, shows the bacterium that causes typhoid fever.
In the picture, of course, it is very greatly magnified. In reality
these bacteria are so small that about twenty-five thousand of them side
by side would extend only one inch. These small beings produce their
great effects by very rapid multiplication and by giving off powerful
poisons.
[Illustration: FIG. 118. FORMS OF BACTERIA
_a_, grippe; _b_, bubonic plague; _c_, diphtheria; _d_, tuberculosis;
_e_, typhoid fever]
Bacteria are so small that they are readily borne on the dust particles
of the air and are often taken into the body through the breath and also
through water or milk. You can therefore see how careful you should be
to prevent germs from getting into the air or into water or milk when
there is disease about your home. You should heed carefully all
instructions of your physician on this point, so that you may not spread
disease.
SECTION XXIX. PREVENTION OF PLANT DISEASE
In the last two sections you have learned something of the nature of
those fungi and bacteria that cause disease in animals and plants. Now
let us see how we can use this knowledge to lessen the diseases of our
crops. Farmers lose through plant diseases much that could be saved by
proper precaution.
First, you must remember that every diseased fruit, twig, or leaf bears
millions of spores. These must be destroyed by burning. They must not be
allowed to lie about and spread the disease in the spring. See that
decayed fruit in the bin or on the trees is destroyed in the same
manner. Never throw decayed fruit into the garden or orchard, as it may
cause disease the following year.
Second, you can often kill spores on seeds before they are planted and
thus prevent the development of the fungus (see pp. 134-137).
Third, often the foliage of the plant can be sprayed with a poison that
will prevent the germination of the spores (see pp. 138-140).
Fourth, some varieties of plants resist disease much more stoutly than
others. We may often select the resistant form to great advantage (see
Fig. 119).
Fifth, after big limbs are pruned off, decay often sets in at the wound.
This decay may be prevented by coating the cut surface with paint, tar,
or some other substance that will not allow spores to enter the wound or
to germinate there.
Sixth, it frequently happens that the spore or fungus remains in the
soil. This is true in the cotton wilt, and the remedy is so to rotate
crops that the diseased land is not used again for this crop until the
spores or fungi have died.
SECTION XXX. SOME SPECIAL PLANT DISEASES
=Fire-Blight of the Pear and Apple.= You have perhaps heard your father
speak of the "fire-blight" of pear and apple trees. This is one of the
most injurious and most widely known of fruit diseases. Do you want to
know the cause of this disease and how to prevent it?
First, how will you recognize this disease? If the diseased bough at
which you are looking has true fire-blight, you will see a blackened
twig with withered, blackened leaves. During winter the leaves do not
fall from blighted twigs as they do from healthy ones. The leaves wither
because of the diseased twig, not because they are themselves diseased.
Only rarely does the blight really enter the leaf. Sometimes a sharp
line separates the blighted from the healthy part of the twig.
This disease is caused by bacteria, of which you have read in another
section. The fire-blight bacteria grow in the juicy part of the stem,
between the wood and the bark. This tender, fresh layer (as explained on
page 79) is called the _cambium_, and is the part that breaks away and
allows you to slip the bark off when you make your bark whistle in the
spring. The growth of new wood takes place in the cambium, and this part
of the twig is therefore full of nourishment. If this nourishment is
stolen the plant of course soon suffers.
The bacteria causing fire-blight are readily carried from flower to
flower and from twig to twig by insects; therefore to keep these and
other bacteria away from your trees you must see to it that all the
trees in the neighborhood of your orchard are kept free from mischievous
enemies. If harmful bacteria exist in near-by trees, insects will carry
them to your orchard. You must therefore watch all the relatives of the
pear; namely, the apple, hawthorn, crab, quince, and mountain ash, for
any of these trees may harbor the germs.
[Illustration: FIG. 119. A RESISTANT VARIETY OF SEA ISLAND COTTON
All the other plants in this field died. This one row lived because it
could resist the cotton wilt]
When any tree shows blight, every diseased twig on it must be cut off
and burned in order to kill the germs, and you must cut low enough on
the twig to get all the bacteria. It is best to cut a foot below the
blackened portion. If by chance your knife should cut into wood
containing the living germs, and then you should cut into healthy wood
with the same knife, you yourself would spread the disease. It is
therefore best after each cutting to dip your knife into a solution of
carbolic acid. This will kill all bacteria clinging to the knife-blade.
The surest time to do complete trimming is after the leaves fall in the
autumn, as diseased twigs are most easily recognized at that time, but
the orchard should be carefully watched in the spring also. If a large
limb shows the blight, it is perhaps best to cut the tree entirely down.
There is little hope for such a tree.
A large pear-grower once said that no man with a sharp knife need fear
the fire-blight. Yet our country loses greatly by this disease each
year.
[Illustration: FIG. 120. FIRE-BLIGHT BACTERIA
Magnified]
It may be added that winter pruning tends to make the tree form much new
wood and thus favors the disease. Rich soil and fertilizers make it much
easier in a similar way for the tree to become a prey to blight.
=EXERCISE=
Ask your teacher to show you a case of fire-blight on a pear or
apple tree. Can you distinguish between healthy and diseased wood?
Cut the twig open lengthwise and see how deep into the wood and how
far down the stem the disease extends. Can you tell surely from the
outside how far the twig is diseased? Can you find any twig that
does not show a distinct line of separation between diseased and
healthy wood? If so, the bacteria are still living in the cambium.
Cut out a small bit of the diseased portion and insert it under the
bark of a healthy, juicy twig within a few inches of its tip and
watch it from day to day. Does the tree catch the disease? This
experiment may prove to you how easily the disease spreads. If you
should see any drops like dew hanging from diseased twigs, touch a
little of this moisture to a healthy flower and watch for results.
Cut and burn all diseased twigs that you can find. Estimate the
damage done by fire-blight.
Farmers' bulletins on orchard enemies are published by the
Department of Agriculture, Washington, D.C., and can be had by
writing for them. They will help your father much in treating
fire-blight.
=Oat Smuts.= Let us go out into a near-by oat field and look for all the
blackened heads of grain that we can find. How many are there? To count
accurately let us select an area one foot square. We must look
carefully, for many of these blackened heads are so low that we shall
not see them at the first glance. You will be surprised to find as many
as thirty or forty heads in every hundred so blackened. These blackened
heads are due to a plant disease called _smut_.
[Illustration: FIG. 121. LOOSE SMUT OF OATS
The glumes at _a_ more nearly destroyed than the glumes at _b_]
When threshing-time comes you will notice a great quantity of black dust
coming from the grain as it passes through the machine. The air is full
of it. This black dust consists of the spores of a tiny fungous plant.
The fungous smut plant grows upon the oat plant, ripens its spores in
the head, and is ready to be thoroughly scattered among the grains of
the oats as they come from the threshing-machine.
These spores cling to the grain and at the next planting are ready to
attack the sprouting plantlet. A curious thing about the smut is that it
can gain a foothold only on very young oat plants; that is, on plants
about an inch long or of the age shown in Fig. 121.
When grain covered with smut spores is planted, the spores develop with
the sprouting seeds and are ready to attack the young plant as it breaks
through the seed-coat. You see, then, how important it is to have seed
grain free from smut. A substance has been found that will, without
injuring the seeds, kill all the smut spores clinging to the grain. This
substance is called _formalin_. Enough seed to plant a whole acre can be
treated with formalin at a cost of only a few cents. Such treatment
insures a full crop and clean seed for future planting. Try it if you
have any smut.
[Illustration: FIG. 122. A CROP FROM OATS TREATED WITH FORMALIN]
Fig. 122 illustrates what may be gained by using seeds treated to
prevent smut. The annual loss to the farmers of the United States from
smut on oats amounts to several millions of dollars. All that is needed
to prevent this loss is a little care in the treatment of seed and a
proper rotation of crops.
=EXERCISE=
Count the smutted heads on a patch three feet square and estimate
the percentage of smut in all the wheat and oat fields near your
home. On which is it most abundant? Do you know of any fields that
have been treated for smut? If so, look for smut in these fields.
Ask how they were treated. Do you know of any one who uses
bluestone for wheat smut? Can oats be treated with bluestone?
At planting time get an ounce of formalin at your drug store or
from the state experiment station. Mix this with three gallons of
water. This amount will treat three bushels of seeds. Spread the
seeds thinly on the barn floor and sprinkle them with the mixture,
being careful that all the seeds are thoroughly moistened. Cover
closely with blankets for a few hours and plant very soon after
treatment. Try this and estimate the per cent of smut at next
harvest-time. Write to your experiment station for a bulletin on
smut treatment.
[Illustration: FIG. 123. A SCABBY SEED POTATO]
[Illustration: FIG. 124. A HEALTHY SEED POTATO]
=Potato Scab.= The scab of the white, or Irish, potato is one of the
commonest and at the same time most easily prevented of plant diseases.
Yet this disease diminishes the profits of the potato-grower very
materially. Fig. 123 shows a very scabby potato, while Fig. 124
represents a healthy one. This scab is caused by a fungous growth on the
surface of the potato. Of course it lessens the selling-price of the
potatoes. If seed potatoes be treated to a bath of formalin just before
they are planted, the formalin will kill the fungi on the potatoes and
greatly diminish the amount of scab at the next harvest. Therefore
before they are planted, seed potatoes should be soaked in a weak
solution of formalin for about two hours. One-half pint of formalin to
fifteen gallons of water makes a proper solution.
[Illustration: FIG. 125
From a scabby potato, like the one in Fig. 123, this yield was obtained]
[Illustration: FIG. 126
From a healthy potato, like the one in Fig. 124, this yield was obtained]
[Illustration: FIG. 127. EFFECT OF SPRAYING
Sprayed potatoes on left; unsprayed on right]
One pint of formalin, or enough for thirty gallons of water, will cost
but thirty-five cents. Since this solution can be used repeatedly, it
will do for many bushels of seed potatoes.
=Late Potato Blight.= The blight is another serious disease of the
potato. This is quite a different disease from the scab and so requires
different treatment. The blight is caused by another fungus, which
attacks the foliage of the potato plant. When the blight seriously
attacks a crop, it generally destroys the crop completely. In the year
1845 a potato famine extending over all the United States and Europe was
caused by this disease.
[Illustration: FIG. 128. YIELD FROM TWO FIELDS OF THE SAME SIZE
The one at the top was sprayed; the one at the bottom was unsprayed]
Spraying is the remedy for potato blight. Fig. 128 shows the effect of
spraying upon the yield. In this case the sprayed field yielded three
hundred and twenty-four bushels an acre, while the unsprayed yielded
only one hundred bushels to an acre. Fig. 127 shows the result of three
applications of the spraying mixture on the diseased field. Figs. 129
and 130 show how the spraying is done.
[Illustration: FIG. 129. SPRAYING MACHINE]
[Illustration: FIG. 130. SPRAYING MACHINE]
=EXERCISE=
Watch the potatoes at the next harvest and estimate the number that
is damaged by scab. You will remember that formalin is the
substance used to prevent grain smuts. Write to your state
experiment station for a bulletin telling how to use formalin, as
well as for information regarding other potato diseases. Give the
treatment a fair trial in a portion of your field this year and
watch carefully for results. Make an estimate of the cost of
treatment and of the profits. How does the scab injure the value of
the potato? The late blight can often be recognized by its odor.
Did you ever smell it as you passed an affected field?
[Illustration: FIG. 131. CLUB ROOT]
=Club Root.= Club root is a disease of the cabbage, turnip, cauliflower,
etc. Its general effect is shown in the illustration (Fig. 131).
Sometimes this disease does great damage. It can be prevented by using
from eighty to ninety bushels of lime to an acre.
=Black Knot.= Black knot is a serious disease of the plum and of the
cherry tree. It attacks the branches of the tree; it is well
illustrated in Fig. 132. Since it is a contagious disease, great care
should be exercised to destroy all diseased branches of either wild or
cultivated plums or cherries. In many states its destruction is enforced
by law. All black knot should be cut out and burned some time before
February of each year. This will cost little and save much.
[Illustration: FIG. 132. BLACK KNOT]
=Peach Leaf Curl.= Peach leaf curl does damage amounting to about
$3,000,000 yearly in the United States. It can be almost entirely
prevented by spraying the tree with Bordeaux mixture or lime-sulphur
wash before the buds open in the spring. It is not safe to use strong
Bordeaux mixture on peach trees when they are in leaf.
[Illustration: FIG. 133. MOLDY PEACHES]
=Cotton Wilt.= Cotton wilt when it once establishes itself in the soil
completely destroys the crop. The fungus remains in the soil, and no
amount of spraying will kill it. The only known remedy is to cultivate a
resistant variety of cotton or to rotate the crop.
[Illustration: FIG. 134. PEACH MUMMIES]
=Fruit Mold.= Fruit mold, or brown rot, often attacks the unripe fruit
on the tree, and turns it soft and brown and finally fuzzy with a coat
of mildew. Fig. 133 shows some peaches thus attacked. Often the fruits
do not fall from the trees but shrivel up and become "mummies" (Fig.
134). This rot is one of the most serious diseases of plums and peaches.
It probably diminishes the value of the peach harvest from 50 to 75 per
cent. Spraying according to the directions in the Appendix will kill the
disease.
[Illustration: FIG. 135. HALF OF TREE SPRAYED TO PREVENT PEACH CURL
Note the difference in foliage and fruit on the sprayed and unsprayed
halves of the tree, and the difference in yield shown below]
CHAPTER VII
ORCHARD, GARDEN, AND FIELD INSECTS
SECTION XXXI. INSECTS IN GENERAL
The farmer who has fought "bugs" on crop after crop needs no argument to
convince him that insects are serious enemies to agriculture. Yet even
he may be surprised to learn that the damage done by them, as estimated
by good authority, amounts to millions and millions of dollars yearly in
the United States and Canada.
[Illustration: FIG. 136. ANTS]
Every one thinks he knows what an insect is. If, however, we are willing
in this matter to make our notion agree with that of the people who have
studied insects most and know them best, we must include among the true
insects only such air-breathing animals as have six legs, no more, and
have the body divided into three parts--head, thorax, and abdomen. These
parts are clearly shown in Fig. 136, which represents the ant, a true
insect. All insects do not show the divisions of the body so clearly as
this figure shows them, but on careful examination you can usually make
them out. The head bears one pair of feelers, and these in many insects
serve also as organs of smell and sometimes of hearing. Less prominent
feelers are to be found in the region of the mouth. These serve as
organs of taste.
[Illustration: FIG. 137. PARTS OF AN INSECT]
[Illustration: FIG. 138. COMPOUND EYE OF DRAGON FLY]
The eyes of insects are especially noticeable. Close examination shows
them to be made up of a thousand or more simple eyes. Such an eye is
called a _compound eye_. An enlarged view of one of these is shown in
Fig. 138.
Attached to the thorax are the legs and also the wings, if the insect
has wings. The rear portion is the abdomen, and this, like the other
parts, is composed of parts known as segments. The insect breathes
through openings in the abdomen and thorax called _spiracles_ (see Fig.
137).
An examination of spiders, mites, and ticks shows eight legs; therefore
these do not belong to the true insects, nor do the thousand-legged
worms and their relatives.
[Illustration: FIG. 139. THE HOUSE FLY
_a_, egg; _b_, larva, or maggot; _c_, pupa; _d_, adult male. (All
enlarged)]
The chief classes of insects are as follows: the flies, with two wings
only; the bees, wasps, and ants, with four delicate wings; the beetles,
with four wings--two hard, horny ones covering the two more delicate
ones. When the beetle is at rest its two hard wings meet in a straight
line down the back. This peculiarity distinguishes it from the true bug,
which has four wings. The two outer wings are partly horny, and in
folding lap over each other. Butterflies and moths are much alike in
appearance but differ in habit. The butterfly works by day and the moth
by night. Note the knob on the end of the butterfly's feeler (Fig. 143).
The moth has no such knob.
It is important to know how insects take their food, for by knowing this
we are often able to destroy insect pests. Some are provided with mouth
parts for chewing their food; others have a long tube with which they
pierce plants or animals and, like the mosquito, suck their food from
the inside. Insects of this latter class cannot of course be harmed by
poison on the surface of the leaves on which they feed.
[Illustration: FIG. 140. A TYPICAL BUG
_a_, adult; _b_, side view of sucking mouth-part Both _a_ and _b_ are
much enlarged]
[Illustration: Fig. 141. BEETLE
_a_, larva; _b_, pupa; _c_, adult; _d_, burrow]
Many insects change their form from youth to old age so much that you
can scarcely recognize them as the same creatures. First comes the egg.
The egg hatches into a worm-like animal known as a grub, maggot, or
caterpillar, or, as scientists call it, a _larva_. This creature feeds
and grows until finally it settles down and spins a home of silk, called
a _cocoon_ (Fig. 145). If we open the cocoon we shall find that the
animal is now covered with a hard outside skeleton, that it cannot move
freely, and that it cannot eat at all. The animal in this state is known
as the _pupa_ (Figs. 145 and 146). Sometimes, however, the pupa is not
covered by a cocoon, sometimes it is soft, and sometimes it has some
power of motion (Fig. 141). After a rest in the pupa stage the animal
comes out a mature insect (Figs. 142 and 143).
From this you can see that it is especially important to know all you
can about the life of injurious insects, since it is often easier to
kill these pests at one stage of their life than at another. Often it is
better to aim at destroying the seemingly harmless beetle or butterfly
than to try to destroy the larvae that hatch from its eggs, although, as
you must remember, it is generally the larvae that do the most harm.
Larvae grow very rapidly; therefore the food supply must be great to meet
the needs of the insect.
[Illustration: FIG. 142. MOTH AND COCOON]
Some insects, the grasshopper for example, do not completely change
their form. Fig. 147 represents some young grasshoppers, which very
closely resemble their parents.
[Illustration: FIG. 143. BUTTERFLY]
[Illustration: FIG. 144. STRUCTURE OF THE CATERPILLAR]
[Illustration: FIG. 145. MOTH PUPA IN COCOON]
Insects lay many eggs and reproduce with remarkable rapidity. Their
number therefore makes them a foe to be much dreaded. The queen honeybee
often lays as many as 4000 eggs in twenty-four hours. A single house fly
lays between 100 and 150 eggs in one day. The mosquito lays eggs in
quantities of from 200 to 400. The white ant often lays 80,000 in a day,
and so continues for two years, probably laying no less than 40,000,000
eggs. In one summer the bluebottle fly could have 500,000,000
descendants if they all lived. The plant louse, at the end of the fifth
brood, has laid in a single year enough eggs to produce 300,000,000
young. Of course every one knows that, owing to enemies and diseases
(for the insects have enemies which prey on them just as they prey on
plants) comparatively few of the insects hatched from these eggs live
till they are grown.
[Illustration: FIG. 146. A BUTTERFLY PUPA
Note outline of the butterfly]
The number of insects which are hurtful to crops, gardens, flowers, and
forests seems to be increasing each season. Therefore farm boys and
girls should learn to recognize these harmful insects and to know how
they live and how they may be destroyed. Those who know the forms and
habits of these enemies of plants and trees are far better prepared to
fight them than are those who strike in the dark. Moreover such
knowledge is always a source of interest and pleasure. If you begin to
study insects, you will soon find your love for the study growing.
[Illustration: FIG. 147. THE GROWTH OF A GRASSHOPPER]
=EXERCISE=
Collect cocoons and pupae of insects and hatch them in a
breeding-cage similar to the one illustrated in Fig. 149. Make
several cages of this kind. Collect larvae of several kinds; supply
them with food from plants upon which you found them. Find out the
time it takes them to change into another stage. Write a
description of this process.
The plant louse could produce in its twelfth brood
10,000,000,000,000,000,000,000 offspring. Each louse is about one
tenth of an inch long. If all should live and be arranged in single
file, how many miles long would such a procession be?
[Illustration: FIG. 148. PLANT LICE]
[Illustration: FIG. 149. CAGE IN WHICH TO BREED INSECTS
Flower-pot, lamp-chimney, and cloth]
SECTION XXXII. ORCHARD INSECTS
=The San Jose Scale.= The San Jose scale is one of the most dreaded
enemies of fruit trees. It is in fact an outlaw in many states. It is an
unlawful act to sell fruit trees affected by it. Fig. 150 shows a view
of a branch nearly covered with this pest. Although this scale is a very
minute animal, yet so rapidly does it multiply that it is very
dangerous to the tree. Never allow new trees to be brought into your
orchard until you feel certain that they are free from the San Jose
scale. If, however, it should in any way gain access to your orchard,
you can prevent its spreading by thorough spraying with what is known as
the lime-sulphur mixture. This mixture has long been used on the Pacific
coast as a remedy for various scale insects. When it was first tried in
other parts of the United States the results were not satisfactory and
its use was abandoned. However, later experiments with it have proved
that the mixture is thoroughly effective in killing this scale and that
it is perfectly harmless to the trees. Until the lime-sulphur mixture
proved to be successful the San Jose scale was a most dreaded nursery
and orchard foe. It was even thought necessary to destroy infected
trees. The lime-sulphur mixture and some other sulphur washes not only
kill the San Jose scale but are also useful in reducing fungous injury.
[Illustration: FIG. 150 SAN JOSE SCALE]
[Illustration: FIG. 151. SINGLE SAN JOSE SCALE
Magnified]
There are several ways of making the lime-sulphur mixture. It is
generally best to buy a prepared mixture from some trustworthy dealer.
If you find the scale on your trees, write to your state experiment
station for directions for combating it.
[Illustration: FIG. 152. THE CODLING MOTH
_a_, burrow of worm in apple; _b_, place where worm enters; _c_, place
where worm leaves; _e_, the larva; _d_, the pupa; _i_, the cocoon; _f_
and _g_, moths; _h_, magnified head of larva]
=The Codling Moth.= The codling moth attacks the apple and often causes
a loss of from twenty-five to seventy-five per cent of the crop. In the
state of New York this insect is causing an annual loss of about three
million dollars. The effect it has on the fruit is most clearly seen in
Fig. 152. The moth lays its egg upon the young leaves just after the
falling of the blossom. She flies on from apple to apple, depositing an
egg each time until from fifty to seventy-five eggs are deposited. The
larva, or "worm," soon hatches and eats its way into the apple. Many
affected apples ripen too soon and drop as "windfalls." Others remain on
the tree and become the common wormy apples so familiar to growers. The
larva that emerges from the windfalls moves generally to a tree, crawls
up the trunk, and spins its cocoon under a ridge in the bark. From the
cocoon the moth comes ready to start a new generation. The last
generation of the larvae spends the winter in the cocoon.
[Illustration: FIG. 153. SPRAYING THE ORCHARD BRINGS LUSCIOUS FRUIT
The picture in the corner at the top shows the right time to spray for
codling moth]
_Treatment._ Destroy orchard trash which may serve as a winter home.
Scrape all loose bark from the tree. Spray the tree with arsenate of
lead as soon as the flowers fall. A former method of fighting this pest
was as follows: bands of burlap four inches wide tied around the tree
furnished a hiding-place for larvae that came from windfalls or crawled
from wormy apples on the tree. The larvae caught under the bands were
killed every five or six days. We know now, however, that a thorough
spraying just after the blossoms fall kills the worms and renders the
bands unnecessary. Furthermore, spraying prevents wormy apples, while
banding does not. Follow the first spraying by a second two weeks later.
It is best to use lime-sulphur mixture or the Bordeaux mixture with
arsenate of lead for a spray. Thus one spraying serves against both
fungi and insects.
[Illustration: FIG. 154. PLUM CURCULIO
Larva, pupa, adult, and mark on the fruit. (Enlarged)]
=The Plum Curculio.= The plum curculio, sometimes called the plum
weevil, is a little creature about one fifth of an inch long. In spite
of its small size the curculio does, if neglected, great damage to our
fruit crop. It injures peaches, plums, and cherries by stinging the
fruit as soon as it is formed. The word "stinging" when applied to
insects--- and this case is no exception--means piercing the object
with the egg-layer (ovipositor) and depositing the egg. Some insects
occasionally use the ovipositor merely for defense. The curculio has an
especially interesting method of laying her egg. First she digs a hole,
in which she places the egg and pushes it well down. Then with her snout
she makes a crescent-shaped cut in the skin of the plum, around the egg.
This mark is shown in Fig. 154. As this peculiar cut is followed by a
flow of gum, you will always be able to recognize the work of the
curculio. Having finished with one plum, this industrious worker makes
her way to other plums until her eggs are all laid. The maggotlike larva
soon hatches, burrows through the fruit, and causes it to drop before
ripening. The larva then enters the ground to a depth of several inches.
There it becomes a pupa, and later, as a mature beetle, emerges and
winters in cracks and crevices.
[Illustration: FIG. 155. LEAF GALLS OF PHYLLOXERA ON CLINTON GRAPE LEAF]
_Treatment._ Burn orchard trash which may serve as winter quarters.
Spraying with arsenate of lead, using two pounds of the mixture to fifty
gallons of water, is the only successful treatment for the curculio. For
plums and peaches, spray first when the fruit is free from the calyx
caps, or dried flower-buds. Repeat the spraying two weeks later. For
late peaches spray a third time two weeks after the second spraying.
This poisonous spray will kill the beetles while they are feeding or
cutting holes in which to lay their eggs.
[Illustration: FIG. 156. THE CANKERWORM]
Fowls in the orchard do good by capturing the larvae before they can
burrow, while hogs will destroy the fallen fruit before the larvae can
escape.
=The Grape Phylloxera.= The grape phylloxera is a serious pest. You have
no doubt seen its galls upon the grape leaf. These galls are caused by a
small louse, the phylloxera. Each gall contains a female, which soon
fills the gall with eggs. These hatch into more females, which emerge
and form new galls, and so the phylloxera spreads (see Fig. 155).
_Treatment._ The Clinton grape is most liable to injury from this pest.
Hence it is better to grow other more resistant kinds. Sometimes the
lice attack the roots of the grape vines. In many sections where
irrigation is practiced the grape rows are flooded when the lice are
thickest. The water drowns the lice and does no harm to the vines.
=The Cankerworm.= The cankerworm is the larva of a moth. Because of its
peculiar mode of crawling, by looping its body, it is often called the
looping worm or measuring worm (Fig. 157, _c_). These worms are such
greedy eaters that in a short time they can so cut the leaves of an
orchard as to give it a scorched appearance. Such an attack practically
destroys the crop and does lasting injury to the tree. The worms are
green or brown and are striped lengthwise. If the tree is jarred, the
worm has a peculiar habit of dropping toward the ground on a silken
thread of its own making (Fig. 156).
[Illustration: FIG. 157. THE SPRING CANKERWORM
_a_, egg mass; _b_, egg, magnified; _c_, larva; _d_, female moth; _e_,
male moth]
In early summer the larvae burrow within the earth and pupate there;
later they emerge as adults (Fig. 157, _d_ and _e_). You observe the
peculiar difference between the wingless female, _d_, and the winged
male, _e_. It is the habit of this wingless female to crawl up the trunk
of some near-by tree in order to deposit her eggs upon the twigs. These
eggs (shown at _a_ and _b_) hatch into the greedy larvae that do so much
damage to our orchards.
Nearly all the common birds feed freely upon the cankerworm, and benefit
the orchard in so doing. The chickadee is perhaps the most useful. A
recent writer is very positive that each chickadee will devour on an
average thirty female cankerworm moths a day; and that if the average
number of eggs laid by each female is one hundred and eighty-five, one
chickadee would thus destroy in one day five thousand five hundred and
fifty eggs, and, in the twenty-five days in which the cankerworm moths
crawl up the tree, would rid the orchard of one hundred and thirty-eight
thousand seven hundred and fifty. These birds also eat immense numbers
of cankerworm eggs before they hatch into worms.
[Illustration: FIG. 158. EGGS OF THE FALL CANKERWORM]
_Treatment._ The inability of the female to fly gives us an easy way to
prevent the larval offspring from getting to the foliage of our trees,
for we know that the only highway open to her or her larvae leads up the
trunk. We must obstruct this highway so that no crawling creature may
pass. This is readily done by smoothing the bark and fitting close to it
a band of paper, and making sure that it is tight enough to prevent
anything from crawling underneath. Then smear over the paper something
so sticky that any moth or larva that attempts to pass will be
entangled. Printer's ink will do very well, or you can buy either
dendrolene or tanglefoot.
[Illustration: FIG. 159. APPLE-TREE TENT CATERPILLAR
_a_, eggs; _b_, cocoon; _c_, caterpillar]
Encourage the chickadee and all other birds, except the English sparrow,
to stay in your orchard. This is easily done by feeding and protecting
them in their times of need.
=The Apple-Tree Tent Caterpillar.= The apple-tree tent caterpillar is a
larva so well known that you only need to be told how to guard against
it. The mother of this caterpillar is a reddish moth. This insect passes
the winter in the egg state securely fastened on the twigs as shown in
Fig. 159, _a_.
_Treatment._ There are three principal methods, (1) Destroy the eggs.
The egg masses are readily seen in winter and may easily be collected
and burned by boys. The chickadee eats great quantities of these eggs.
(2) With torches burn the nests at dusk when all the worms are within.
You must be very careful in burning or you will harm the young branches
with their tender bark. (3) Encourage the residence of birds. Urge your
neighbors to make war on the larvae, too, since the pest spreads rapidly
from farm to farm. Regularly sprayed orchards are rarely troubled by
this pest.
[Illustration: FIG. 160. THE TWIG GIRDLER AT ITS DESTRUCTIVE WORK
_a_, the girdler; _b_, the egg-hole; _c_, the groove cut by girdler;
_e_, the egg]
=The Twig Girdler.= The twig girdler lays her eggs in the twigs of pear,
pecan, apple, and other trees. It is necessary that the larvae develop in
dead wood. This the mother provides by girdling the twig so deeply that
it will die and fall to the ground.
_Treatment._ Since the larvae spend the winter in the dead twigs, burn
these twigs in autumn or early spring and thus destroy the pest.
=The Peach-Tree Borer.= In Fig. 161 you see the effect of the peach-tree
borer's activity. These borers often girdle and thereby kill a tree.
Fig. 162 shows the adult state of the insect. The eggs are laid on peach
or plum trees near the ground. As soon as the larva emerges, it bores
into the bark and remains there for months, passing through the pupa
stage before it comes out to lay eggs for another generation.
[Illustration: FIG. 161. BORER SIGNS AROUND BASE OF PEACH TREE]
_Treatment._ If there are only a few trees in the orchard, digging the
worms out with a knife is the best way of destroying them. You can know
of the borer's presence by the exuding gum often seen on the tree-trunk.
If you pile earth around the roots early in the spring and remove it in
the late fall, the winter freezing and thawing will kill many of the
larvae.
=EXERCISE=
How many apples per hundred do you find injured by the codling
moth? Collect some cocoons from a pear or an apple tree in winter,
place in a breeding-cage, and watch for the moths that come out. Do
you ever see the woodpecker hunting for these same cocoons? Can you
find cocoons that have been emptied by this bird? Estimate how many
he considers a day's ration. How many apples does he thus save?
[Illustration: FIG. 162. PEACH-TREE BORERS, MALE AND FEMALE
Female with broad yellow band across abdomen]
Watch the curculio lay her eggs in the plums, peaches, or cherries.
What per cent of fruit is thus injured? Estimate the damage. Let
the school offer a prize for the greatest number of
tent-caterpillar eggs. Watch such trees as the apple, the wild and
the cultivated cherry, the oak, and many others.
Make a collection of insects injurious to orchard fruits, showing
in each case the whole life history of the insect, that is, eggs,
larva, pupa, and the mature insects.
[Illustration: THE TROUBLESOME CHINCH BUG (ENLARGED)
1, bugs on plant; 2, eggs; 3, young bug; 4 and 5, older bugs; 6,
long-winged bug; 7 and 8, short-winged bug]
SECTION XXXIII. GARDEN AND FIELD INSECTS
=The Cabbage Worm.= The cabbage worm of the early spring garden is a
familiar object, but you may not know that the innocent-looking little
white butterflies hovering about the cabbage patch are laying eggs which
are soon to hatch and make the dreaded cabbage worms. In Fig. 164 _a_
and _b_ show the common cabbage butterfly, _c_ shows several examples of
the caterpillar, and _d_ shows the pupa case. In the pupa stage the
insects pass the winter among the remains of old plants or in near-by
fences or in weeds or bushes. Cleaning up and burning all trash will
destroy many pupae and thus prevent many cabbage worms. In Fig. 164 _e_
and _f_ show the moth and zebra caterpillar; _g_ represents a moth which
is the parent of the small green worm shown at _h_. This worm is a
common foe of the cabbage plant.
[Illustration: FIG. 163. THE DREADED CHINCH BUG]
_Treatment._ Birds aid in the destruction of this pest. Paris green
mixed with air-slaked lime will also kill many larvae. After the cabbage
has headed, it is very difficult to destroy the worm, but pyrethrum
insect powder used freely is helpful.
=The Chinch Bug.= The chinch bug, attacking as it does such important
crops as wheat, corn, and grasses, is a well-known pest. It probably
causes more money loss than any other garden or field enemy. In Orange
county, North Carolina, farmers were once obliged to suspend
wheat-growing for two years on account of the chinch bug. In one year in
the state of Illinois this bug caused a loss of four million dollars.
[Illustration: FIG. 164. CABBAGE WORMS AND BUTTERFLIES]
_Treatment._ Unfortunately we cannot prevent all of the damage done by
chinch bugs, but we can diminish it somewhat by good clean agriculture.
Destroy the winter homes of the insect by burning dry grass, leaves, and
rubbish in fields and fence rows. Although the insect has wings, it
seldom or never uses them, usually traveling on foot; therefore a deep
furrow around the field to be protected will hinder or stop the progress
of an invasion. The bugs fall into the bottom of the furrow, and may
there be killed by dragging a log up and down the furrow. Write to the
Division of Entomology, Washington, for bulletins on the chinch bug.
Other methods of prevention are to be found in these bulletins.
[Illustration: FIG. 165. A PLANT LOUSE COLONY]
=The Plant Louse.= The plant louse is very small, but it multiplies with
very great rapidity. During the summer the young are born alive, and it
is only toward fall that eggs are laid. The individuals that hatch from
eggs are generally wingless females, and their young, born alive, are
both winged and wingless. The winged forms fly to other plants and start
new colonies. Plant lice mature in from eight to fourteen days.
The plant louse gives off a sweetish fluid of which some ants are very
fond. You may often see the ants stroking these lice to induce them to
give off a freer flow of the "honey dew." This is really a method of
milking. However friendly and useful these "cows" may be to the ant,
they are enemies to man in destroying so many of his plants.
_Treatment._ These are sucking insects. Poisons therefore do not avail.
They may be killed by spraying with kerosene emulsion or a strong soap
solution or with tobacco water. Lice on cabbages are easily killed by a
mixture of one pound of lye soap in four gallons of warm water.
[Illustration: FIG. 166. A CHEAP SPRAYING OUTFIT]
=The Squash Bug.= The squash bug does its greatest damage to young
plants. To such its attack is often fatal. On larger plants single
leaves may die. This insect is a serious enemy to a crop and is
particularly difficult to get rid of, since it belongs to the class of
sucking insects, not to the biting insects. For this reason poisons are
useless.
[Illustration: FIG. 167. A SQUASH BUG]
_Treatment._ About the only practicable remedy is to pick these insects
by hand. We can, however, protect our young plants by small nettings and
thus tide them over the most dangerous period of their lives. These bugs
greatly prefer the squash as food. You can therefore diminish their
attack on your melons, cucumbers, etc. by planting among the melons an
occasional squash plant as a "trap plant." Hand picking will be easier
on a few trap plants than over the whole field. A small board or large
leaf laid beside the young plant often furnishes night shelter for the
bugs. The bugs collected under the board may easily be killed every
morning.
=The Flea-Beetle.= The flea-beetle inflicts much damage on the potato,
tomato, eggplant, and other garden plants. The accompanying figure shows
the common striped flea-beetle which lives on the tomato. The larva of
this beetle lives inside of the leaves, mining its way through the leaf
in a real tunnel. Any substance disagreeable to the beetle, such as
plaster, soot, ashes, or tobacco, will repel its attacks on the garden
crops.
[Illustration: FIG. 168. FLEA-BEETLE AND LARVA
_a_, larva; _b_, adult. Lines on sides show real length of insects]
=The Weevil.= The weevil is commonly found among seeds. Its attacks are
serious, but the insect may easily be destroyed.
_Treatment._ Put the infected seeds in an air-tight box or bin, placing
on the top of the pile a dish containing carbon disulphide, a
tablespoonful to a bushel of seeds. The fumes of this substance are
heavy and will pass through the mass of seeds below and kill all the
weevils and other animals there. The bin should be closely covered with
canvas or heavy cloth to prevent the fumes from being carried away by
the air. Let the seeds remain thus from two to five days. Repeat the
treatment if any weevils are found alive. Fumigate when the temperature
is 70 deg. Fahrenheit or above. In cold weather or in a loose bin the
treatment is not successful. _Caution:_ Do not approach the bin with a
light, since the fumes of the chemical used are highly inflammable.
=The Hessian Fly.= The Hessian fly does more damage to the wheat crop
than all other insects combined, and probably ranks next to the chinch
bug as the second worst insect enemy of the farmer. It was probably
introduced into this country by the Hessian troops in the War of the
Revolution.
[Illustration: FIG. 169. THE HESSIAN FLY]
In autumn the insect lays its eggs in the leaves of the wheat. These
hatch into the larvae, which move down into the crown of the plant, where
they pass the winter. There they cause on the plant a slight gall
formation, which injures or kills the plant. In the spring adult flies
emerge and lay eggs. The larvae that hatch feed in the lower joints of
the growing wheat and prevent its proper growth. These larvae pupate and
remain as pupae in the wheat stubble during the summer. The fall brood of
flies appears shortly before the first heavy frost.
_Treatment._ Burn all stubble and trash during July and August. If the
fly is very bad, it is well to leave the stubble unusually high to
insure a rapid spread of the fire. Burn refuse from the
threshing-machine, since this often harbors many larvae or pupae. Follow
the burning by deep plowing, because the burning cannot reach the
insects that are in the base of the plants. Delay the fall planting
until time for heavy frosts.
=The Potato Beetle; Tobacco Worm.= The potato beetle, tobacco worm,
etc., are too well known to need description. Suffice it to say that no
good farmer will neglect to protect his crop from any pest that
threatens it.
The increase, owing to various causes, of insects, of fungi, of
bacterial diseases, makes a study of these pests, of their origin, and
of their prevention a necessary part of a successful farmer's training.
Tillage alone will no longer render orchard, vineyard, and garden
fruitful. Protection from every form of plant enemies must be added to
tillage.
[Illustration: FIG. 170. SPRAYING THE ORCHARD
One way of increasing the yield of fruit]
In dealing with plants, as with human beings, the great object should be
not the cure but the prevention of disease. If disease can be prevented,
it is far too costly to wait for it to develop and then to attempt its
cure. Men of science are studying the new forms of diseases and new
insects as fast as they appear. These men are finding ways of fighting
old and new enemies. Young people who expect to farm should early learn
to follow their advice.
=EXERCISE=
How does the squash bug resemble the plant louse? Is this a true
bug? Gather some eggs and watch the development of the insects in a
breeding-cage. Estimate the damage done to some crops by the
flea-beetle. What is the best method of prevention?
[Illustration: FIG. 171. AN APPLE TREE SHOWING PROPER CARE]
Do you know the large moth that is the mother of the tobacco worm?
You may often see her visiting the blossoms of the Jimson weed.
Some tobacco-growers cultivate a few of these weeds in a tobacco
field. In the blossom they place a little cobalt or "fly-stone" and
sirup. When the tobacco-worm moth visits this flower and sips the
poisoned nectar, she will of course lay no more troublesome eggs.
SECTION XXXIV. THE COTTON-BOLL WEEVIL
So far as known, the cotton-boll weevil, an insect which is a native of
the tropics, crossed the Rio Grande River into Texas in 1891 and 1892.
It settled in the cotton fields around Brownsville. Since then it has
widened its destructive area until now it has invaded the whole
territory shown by the map on page 177.
[Illustration: FIG. 172. ADULT COTTON-BOLL WEEVIL
Enlarged]
This weevil is a small gray or reddish-brown snout-beetle hardly over a
quarter of an inch in length. In proportion to its length it has a long
beak. It belongs to a family of beetles which breed in pods, in seeds,
and in stalks of plants. It is a greedy eater, but feeds only on the
cotton plant.
The grown weevils try to outlive the cold of winter by hiding snugly
away under grass clumps, cotton-stalks, rubbish, or under the bark of
trees. Sometimes they go down into holes in the ground. A comfortable
shelter is often found in the forests near the cotton fields, especially
in the moss on the trees. The weevils can stand a good deal of cold, but
fortunately many are killed by winter weather. Moreover birds destroy
many; hence by spring the last year's crop is very greatly diminished.
In the spring, generally about the time cotton begins to form "squares,"
the weevils shake off their long winter sleep and enter the cotton
fields with appetites as sharp as razors. Then shortly the females begin
to lay eggs. At first these eggs are laid only in the squares, and
generally only one to the square. The young grub hatches from these eggs
in two or three days. The newly hatched grub eats the inside of the
square, and the square soon falls to the ground. Entire fields may at
times be seen without a single square on the plants. Of course no fruit
can be formed without squares.
[Illustration: FIG. 173. EGGS AMONG THE ANTHERS OF A SQUARE AT THE
POINT INDICATED BY THE ARROW]
[Illustration: FIG. 174. CROSS SECTION SHOWING ANTHERS OF A SQUARE
WITH EGG OF WEEVIL, AND SHOWING THE HOLE WHERE THE EGG WAS DEPOSITED
Greatly enlarged]
In from one to two weeks the grub or larva becomes fully grown and,
without changing its home, is transformed into the pupa state. Then in
about a week more the pupae come out as adult weevils and attack the
bolls. They puncture them with their snouts and lay their eggs in the
bolls. The young grubs, this time hatching out in the boll, remain there
until grown, when they emerge through holes that they make. These holes
allow dampness to enter and destroy the bolls. This life-round continues
until cold weather drives the insects to their winter quarters. By that
time they have increased so rapidly that there is often one for every
boll in the field.
[Illustration: FIG. 175. THE LARVA OF THE COTTON-BOLL WEEVIL
INJURING A SQUARE]
This weevil is proving very hard to destroy. At present there seem but
few ways to fight it. One is to grow cotton that will mature too early
for the weevils to do it much harm. A second is to kill as many weevils
as possible by burning the homes that shelter them in winter.
[Illustration: FIG. 176. PUPA OF COTTON-BOLL WEEVIL FROM ABOVE AND BELOW
Greatly enlarged]
[Illustration: FIG. 177. THE PUPA OF THE COTTON-BOLL WEEVIL IN A SQUARE]
The places best adapted for a winter home for the weevil are trash
piles, rubbish, driftwood, rotten wood, weeds, moss on trees, etc. A
further help, therefore, in destroying the weevil is to cut down and
burn all cotton-stalks as soon as the cotton is harvested.
[Illustration: FIG. 178. A COTTON BOLL WITH FEEDING-HOLES OF WEEVIL,
AND BEARING THREE SPECIMENS OF THE INSECT]
[Illustration: FIG. 179. THE MEXICAN COTTON-BOLL WEEVIL,
SHOWING STRUCTURE]
This destroys countless numbers of larvae and pupae in the bolls and
greatly reduces the number of weevils. In addition, all cornstalks, all
trash, all large clumps of grass in neighboring fields, should be
burned, so as to destroy these winter homes of the weevil. Also avoid
planting cotton near trees. The bark, moss, and fallen leaves of the
tree furnish a winter shelter for the weevils.
[Illustration: FIG. 180. A SERIES OF FULL GROWN WEEVILS, SHOWING
VARIATIONS IN SIZE]
A third help in destroying the weevil is to rotate crops. If cotton does
not follow cotton, the weevil has nothing on which to feed the second
year.
[Illustration: FIG. 181. MAP SHOWING DISTRIBUTION OF THE COTTON-BOLL
WEEVIL IN 1913]
In adopting the first method mentioned the cotton growers have found
that by the careful selection of seed, by early planting, by a free use
of fertilizers containing phosphoric acid, and by frequent plowing, they
can mature a crop about thirty days earlier than they usually do. In
this way a good crop can be harvested before the weevils are ready to be
most destructive.
CHAPTER VIII
FARM CROPS
Every crop of the farm has been changed and improved in many ways since
its forefathers were wild plants. Those plants that best serve the needs
of the farmer and of farm animals have undergone the most changes and
have received also the greatest care and attention in their production
and improvement.
While we have many different kinds of farm crops, the cultivated soil of
the world is occupied by a very few. In our country the crop that is
most valuable and that occupies the greatest land area is generally
known as the _grass crop_. Included in the general term "grass crop" are
the grasses and clovers that are used for pasturage as well as for hay.
Next to grass in value come the great cereal, corn, and the most
important fiber crop, cotton, closely followed by the great bread crop,
wheat. Oats rank fifth in value, potatoes sixth, and tobacco seventh.
(These figures are for 1913.)
Success in growing any crop is largely due to the suitableness of soil
and climate to that crop. When the planter selects both the most
suitable soil and the most suitable climate for each crop, he gets not
only the most bountiful yield from the crop but, in addition, he gets
the most desirable quality of product. A little careful observation and
study soon teach what kinds of soil produce crops of the highest
excellence. This learned, the planter is able to grow in each field the
several crops best adapted to that special type of soil. Thus we have
tobacco soils, trucking soils, wheat and corn soils. Dairying can be
most profitably followed in sections where crops like cowpeas, clover,
alfalfa, and corn are peculiarly at home. No one should try to grow a
new crop in his section until he has found out whether the crop which he
wants to grow is adapted to his soil and his climate.
[Illustration: FIG. 182. ALFALFA IN THE STACK
This is the second cutting of the season]
The figures below give the average amount of money made annually an acre
on our chief crops:
Flowers and plants, $1911; nursery products, $261; onions, $140; sugar
cane, $55; small fruits, $110; hops, $175; vegetables, $78; tobacco,
$80; sweet potatoes, $55; hemp, $53; potatoes, $78; sugar beets, $54;
sorghum cane, $22; cotton, $22; orchard fruits, $110; peanuts, $21;
flax-seed, $14; cereals, $14; hay and forage, $11; castor beans, $6
(United States Census Report).
SECTION XXXV. COTTON
Although cotton was cultivated on the Eastern continent before America
was discovered, this crop owes its present kingly place in the business
world to the zeal and intelligence of its American growers. So great an
influence does it wield in modern industrial life that it is often
called King Cotton. Thousands upon thousands of people scan the
newspapers each day to see what price its staple is bringing. From its
bounty a vast army of toilers, who plant its seed, who pick its bolls,
who gin its staple, who spin and weave its lint, who grind its seed, who
refine its oil, draw daily bread. Does not its proper production deserve
the best thought that can be given it?
In the cotton belt almost any well-drained soil will produce cotton. The
following kinds of soil are admirably suited to this plant: red and gray
loams with good clay subsoil; sandy soils over clay and sandstone and
limestone; rich, well-drained bottom-lands. The safest soils are medium
loams. Cotton land must always be well drained.
Cotton was originally a tropical plant, but, strange to say, it seems to
thrive best in temperate zones. The cotton plant does best, according to
Newman, in climates which have (1) six months of freedom from frost; (2)
a moderate, well-distributed rainfall during the plant's growing period;
and (3) abundant sunshine and little rain during the plant's maturing
period.
[Illustration: FIG. 183. GROWTH OF COTTON FROM DAY TO DAY
In America the Southern states from Virginia to Texas have these
climatic qualities, and it is in these states that the cotton industry
has been developed until it is one of the giant industries of the world.
This development has been very rapid. As late as 1736 the cotton plant
was grown as an ornamental flowering plant in many front yards; in
1911, 16,250,276 bales of cotton were grown in the South. In recent
years the soil and climate of lower California and parts of Arizona and
New Mexico have been found well adapted to cotton.
[Illustration: FIG. 184. COTTON IN THE GROWING SEASON]
There are a great many varieties of cotton. Two types are mainly grown
by the practical American farmer. These are the short-stapled, upland
variety most commonly grown in all the Southern states, and the
beautiful, long-stapled, black-seeded sea-island type that grows upon
the islands and a portion of the mainland of Georgia, South Carolina,
and Florida. The air of the coast seems necessary for the production of
this latter variety. The seeds of the sea-island cotton are small,
smooth, and black. They are so smooth and stick so loosely to the lint
that they are separated from it by roller-gins instead of by saw-gins.
When these seeds are planted away from the soil and air of their ocean
home, the plant does not thrive.
Many attempts have been made and are still being made to increase the
length of the staple of the upland types. The methods used are as
follows: selection of seed having a long fiber; special cultivation and
fertilization; crossing the short-stapled cotton on the long-stapled
cotton. This last process, as already explained, is called
_hybridizing_. Many of these attempts have succeeded, and there are now
a large number of varieties which excel the older varieties in
profitable yield. The new varieties are each year being more widely
grown. Every farmer should study the new types and select the one that
will best suit his land. The new types have been developed under the
best tillage. Therefore if a farmer would keep the new type as good as
it was when he began to grow it, he must give it the same good tillage,
and practice seed-selection.
[Illustration: FIG. 185. COTTON READY FOR PICKING]
The cotton plant is nourished by a tap-root that will seek food as
deeply as loose earth will permit the root to penetrate; hence, in
preparing land for this crop the first plowing should be done at least
with a two-horse plow and should be deep and thorough. This deep plowing
not only allows the tap-root to penetrate, but it also admits a
circulation of air.
On some cotton farms it is the practice to break the land in winter or
early spring and then let it lie naked until planting-time. This is not
a good practice. The winter rains wash more plant food out of
unprotected soil than a single crop would use. It would be better, in
the late summer or fall, to plant crimson clover or some other
protective and enriching crop on land that is to be planted in cotton in
the spring. This crop, in addition to keeping the land from being
injuriously washed, would greatly help the coming cotton crop by leaving
the soil full of vegetable matter.
In preparing for cotton-planting, first disk the land thoroughly, then
break with a heavy plow and harrow until a fine and mellow seed-bed is
formed. Do not spare the harrow at this time. It destroys many a weed
that, if allowed to grow, would have to be cut by costly hoeing.
Thorough work before planting saves much expensive work in the later
days of the crop. Moreover, no man can afford to allow his plant food
and moisture to go to nourish weeds, even for a short time.
The rows should be from three to four feet apart. The width depends upon
the richness of the soil. On rich land the rows should be at least four
feet apart. This width allows the luxuriant plant to branch and fruit
well. On poorer lands the distance of the rows should not be so great.
The distribution of the seed in the row is of course most cheaply done
by the planter. As a rule it is best not to ridge the land for the seed.
Flat culture saves moisture and often prevents damage to the roots. In
some sections, however, where the land is flat and full of water,
ridging seems necessary if the land cannot be drained.
[Illustration: FIG. 186. PICKING COTTON]
The cheapest way of cultivating a crop is to prevent grass and weeds
from rooting, not to wait to destroy them after they are well rooted. To
do this, it is well to run the two-horse smoothing-harrow over the
land, across the rows, a few days after the young plants are up. Repeat
the harrowing in six or eight days. In addition to destroying the young
grass and weeds, this harrowing also removes many of the young cotton
plants and thereby saves much hoeing at "chopping-out" time. When the
plants are about two inches high they are "chopped out" to secure an
evenly distributed stand. It has been the custom to leave two stalks to
a hill, but many growers are now leaving only one.
The number of times the crop has to be worked depends on the soil and
the season. If the soil is dry and porous, cultivate as often as
possible, especially after each rain. Never allow a crust to form after
a rain; the roots of plants must have air. Cultivation after each rain
forms a dry mulch on the top of the soil and thus prevents rapid
evaporation of moisture.
If the fiber (the lint) only is removed from the land on which cotton is
grown, cotton is the least exhaustive of the great crops grown in the
United States. According to some recent experiments an average crop of
cotton removes in the lint only 2.75 pounds of nitrogen, phosphoric
acid, potash, lime, and magnesia per acre, while a crop of ten bushels
of wheat per acre removes 32.36 pounds of the same elements of plant
food. Inasmuch as this crop takes so little plant food from the soil,
the cotton-farmer has no excuse for allowing his land to decrease in
productiveness. Two things will keep his land in bounteous harvest
condition: first, let him return the seeds in some form to the land, or,
what is better, feed the ground seeds to cattle, make a profit from the
cattle, and return manure to the land in place of the seeds; second, at
the last working, let him sow some crop like crimson clover or rye in
the cotton rows to protect the soil during the winter and to leave humus
in the ground for the spring.
The stable manure, if that is used, should be broadcasted over the
fields at the rate of six to ten tons an acre. If commercial fertilizers
are used, it may be best to make two applications. To give the young
plants a good start, apply a portion of the fertilizer in the drill just
before planting. Then when the first blooms appear, put the remainder of
the fertilizer in drills near the plants but not too close. Many good
cotton-growers, however, apply all the fertilizer at one time.
[Illustration: FIG. 187. WEIGHING A DAY'S PICKING OF COTTON]
_Relation of Stock to the Cotton Crop_. On many farms much of the money
for which the cotton is sold in the fall has to go to pay for the
commercial fertilizer used in growing the crop. Should not this fact
suggest efforts to raise just as good crops without having to buy so
much fertilizer? Is there any way by which this can be done? The
following suggestions may be helpful. Raise enough stock to use all the
cotton seed grown on the farm. To go with the food made from the cotton
seed, grow on the farm pea-vine hay, clover, alfalfa, and other such
nitrogen-gathering crops. This can be done at small cost. What will be
the result?
First, to say nothing of the money made from the cattle, the large
quantity of stable manure saved will largely reduce the amount of
commercial fertilizer needed. The cotton-farmer cannot afford to neglect
cattle-raising. The cattle sections of the country are likely to make
the greatest progress in agriculture, because they have manure always on
hand.
[Illustration: FIG. 188. MODERN COTTON BALES]
Second, the nitrogen-gathering crops, while helping to feed the stock,
also reduce the fertilizer bills by supplying one of the costly elements
of the fertilizer. The ordinary cotton fertilizer consists principally
of nitrogen, of potash, and of phosphoric acid. Of these three, by far
the most costly is nitrogen. Now peas, beans, clover, and peanuts will
leave enough nitrogen in the soil for cotton, so that if they are
raised, it is necessary to buy only phosphoric acid and sometimes
potash.
SECTION XXXVI. TOBACCO
The tobacco plant connects Indian agriculture with our own. It has
always been a source of great profit to our people. In the early
colonial days tobacco was almost the only money crop. Many rich men came
to America in those days merely to raise tobacco.
Although tobacco will grow in almost any climate, the leaves, which, as
most of you know, are the salable part of the plant, get their desirable
or undesirable qualities very largely from the soil and from the climate
in which they grow.
The soil in which tobacco thrives best is one which has the following
qualities: dryness, warmth, richness, depth, and sandiness.
Commercial fertilizers also are almost a necessity; for, as tobacco land
is limited in area, the same land must be often planted in tobacco.
Hence even a fresh, rich soil that did not at first require fertilizing
soon becomes exhausted, and, after the land has been robbed of its plant
food by crop after crop of tobacco, frequent application of fertilizers
and other manures becomes necessary. However, even tobacco growers
should rotate their crops as much as possible.
[Illustration: FIG. 189. A LEAF OF TOBACCO]
Deep plowing--from nine to thirteen inches--is also a necessity in
preparing the land, for tobacco roots go deep into the soil. After this
deep plowing, harrow until the soil is thoroughly pulverized and is as
fine and mellow as that of the flower-garden.
Unlike most other farm crops the tobacco plant must be started first in
a seed-bed. To prepare a tobacco bed the almost universal custom has
been to proceed as follows. Carefully select a protected spot. Over this
spot pile brushwood and then burn it. The soil will be left dry, and all
the weed seeds will be killed. The bed is then carefully raked and
smoothed and planted. Some farmers are now preparing their beds without
burning. A tablespoonful of seed will sow a patch twenty-five feet
square. A cheap cloth cover is put over the bed. If the seeds come up
well, a patch of this size ought to furnish transplants for five or six
acres. In sowing, it is not wise to cover the seed deeply. A light
raking in or an even rolling of the ground is all that is needed.
[Illustration: FIG. 190. A PROMISING CROP OF TOBACCO]
The time required for sprouting is from two to three weeks. The plants
ought to be ready for transplanting in from four to six weeks. Weeds
and grass should of course be kept out of the seed-bed.
The plants, when ready, are transplanted in very much the same way as
cabbages and tomatoes. The transplanting was formerly done by hand, but
an effective machine is now widely used. The rows should be from three
to three and a half feet apart, and the plants in the rows about two or
three feet apart. If the plants are set so that the plow and cultivator
can be run with the rows and also across the rows, they can be more
economically worked. Tobacco, like corn, requires shallow cultivation.
Of course the plants should be worked often enough to give clean culture
and to provide a soil mulch for saving moisture.
[Illustration: FIG. 191. TOPPING TOBACCO]
In tobacco culture it is necessary to pinch off the "buttons" and to cut
off the tops of the main stalk, else much nourishment that should go to
the leaves will be given to the seeds. The suckers must also be cut off
for the same reason.
The proper time for harvesting is not easily fixed; one becomes skillful
in this work only through experience in the field. Briefly, we may say
that tobacco is ready to be cut when the leaves on being held up to the
sun show a light or golden color, when they are sticky to the touch, and
when they break easily on being bent. Plants that are overripe are
inferior to those that are cut early.
The operations included in cutting, housing, drying, shipping, sweating,
and packing require skill and practice.
SECTION XXXVII. WHEAT
Wheat has been cultivated from earliest times. It was a chief crop in
Egypt and Palestine, and still holds its importance in the temperate
portions of Europe, Asia, Africa, Australia, and America.
[Illustration: FIG. 192. A HAND]
[Illustration: FIG. 193. WHEAT HEADS]
This crop ranks third in value in the United States. It grows in cool,
in temperate, and in warm climates, and in many kinds of soil. It does
best in clay loam, and worst in sandy soils. Clogged and water-soaked
land will not grow wheat with profit to the farmer; for this reason,
where good wheat-production is desired the soil must be well drained
and in good physical condition--that is, the soil must be open, crumbly,
and mellow.
Clay soils that are hard and lifeless can be made valuable for
wheat-production by covering the surface with manure, by good tillage,
and by a thorough system of crop-rotation. Cowpeas and other legumes
make a most valuable crop to precede wheat, for in growing they add
atmospheric nitrogen to the soil, and their roots loosen the root-bed,
thereby admitting a free circulation of air and adding humus to the
soil. Moreover, the legumes leave the soil with its grains fairly close
packed, and this is a help in wheat growing.
One may secure a good seed-bed after cotton and corn as well as after
cowpeas and other legumes. They are summer-cultivated crops, and the
clean culture that has been given them renders the surface soil mellow
and the undersoil firm and compact. They are not so good, however, as
cowpeas, since they add no atmospheric nitrogen to the soil, as all
leguminous crops do.
[Illustration: FIG. 194. ROOTS OF A SINGLE WHEAT PLANT]
From one to two inches is the most satisfactory depth for planting
wheat. The largest number of seeds comes up when planted at this depth.
A mellow soil is very helpful to good coming up and provides a most
comfortable home for the roots of the plant. A compact soil below makes
a moist undersoil; and this is desirable, for the soil water is needed
to dissolve plant food and to carry it up through the plant, where it is
used in building tissue.
There are a great many varieties of wheat: some are bearded, others are
smooth; some are winter and others are spring varieties. The
smooth-headed varieties are most agreeable to handle during harvest and
at threshing-time. Some of the bearded varieties, however, do so well in
some soils and climates that it is desirable to continue growing them,
though they are less agreeable to handle. No matter what variety you are
accustomed to raise, it may be improved by careful seed-selection.
[Illustration: FIG. 195. SELECTING WHEAT SEED]
The seed-drill is the best implement for planting wheat. It distributes
the grains evenly over the whole field and leaves the mellow soil in a
condition to catch what snow may fall and secure what protection it
affords.
[Illustration: FIG. 196. ADJOINING WHEAT FIELDS
The yield of the lower field, forty-five bushels per acre, is due to
intelligent farming]
In many parts of the country, because not enough live stock is raised,
there is often too little manure to apply to the wheat land. Where this
is the case commercial fertilizers must be used. Since soils differ
greatly, it is impossible to suggest a fertilizer adapted to all soils.
The elements usually lacking in wheat soils are nitrogen, phosphoric
acid, and potash. The land may be lacking in one of these plant foods or
in all; in either case a maximum crop cannot possibly be raised. The
section on manuring the soil will be helpful to the wheat-grower.
[Illustration: FIG. 197. A BOUNTIFUL CROP OF WHEAT]
It should be remembered always in buying fertilizers for wheat that
whenever wheat follows cowpeas or clover or other legumes there is
seldom need of using nitrogen in the fertilizer; the tubercles on the
pea or clover roots will furnish that. Hence, as a rule, only potash and
phosphoric acid will have to be purchased as plant food.
The farmer is assisted always by a study of his crop and by a knowledge
of how it grows. If he find the straw inferior and short, it means that
the soil is deficient in nitrogen; but on the other hand, if the straw
be luxuriant and the heads small and poorly filled, he may be sure that
his soil contains too little phosphoric acid and potash.
=EXERCISE=
Let the pupils secure several heads of wheat and thresh each
separately by hand. The grains should then be counted and their
plumpness and size observed. The practical importance of this is
obvious, for the larger the heads and the greater the number of
grains, the larger the yield per acre. Let them plant some of the
large and some of the small grains. A single test of this kind will
show the importance of careful seed-selection.
[Illustration: FIG. 198 A WIDELY GROWN CROP]
SECTION XXXVIII. CORN
When the white man came to this country he found the Indians using corn;
for this reason, in addition to its name _maize_, it is called _Indian
corn_. Before that time the civilized world did not know that there was
such a crop. The increase in the yield and the extension of the acres
planted in this strictly American crop have kept pace with the rapid
and wonderful growth of our country. Corn is king of the cereals and the
most important crop of American agriculture. It grows in almost every
section of America. There is hardly any limit to the uses to which its
grain and its stalks are now put. Animals of many kinds are fed on
rations into which it enters. Its grains in some form furnish food to
more people than does any other crop except possibly rice. Its stalk and
its cob are manufactured into many different and useful articles.
A soil rich in either decaying animal or vegetable matter, loose, warm,
and moist but not wet, will produce a better crop of corn than any
other. Corn soil should always be well tilled and cultivated.
The proper time to begin the cultivation of corn is before it is
planted. Plow well. A shallow, worn-out soil should not be used for
corn, but for cowpeas or rye. After thorough plowing, the harrow--either
the disk or spring-tooth--should be used to destroy all clods and leave
the surface mellow and fine. The best results will be obtained by
turning under a clover sod that has been manured from the savings of the
barnyard.
When manure is not available, commercial fertilizers will often prove
profitable on poor lands. Careful trials will best determine how much
fertilizer to an acre is necessary, and what kinds are to be used. A
little study and experimenting on the farmer's part will soon enable him
to find out both the kind and the amount of fertilizer that is best
suited to his land.
The seed for this crop should be selected according to the plan
suggested in Section XIX.
[Illustration: FIG. 199. CORN SHOCKED FOR THE SHREDDER]
The most economical method of planting is by means of the horse planter,
which, according to its adjustment, plants regularly in hills or in
drills. A few days after planting, the cornfield should be harrowed with
a fine-tooth harrow to loosen the top soil and to kill the grass and the
weed seeds that are germinating at the surface. When the corn plants
are from a half inch to an inch high, the harrow may again be used. A
little work before the weeds sprout will save many days of labor during
the rest of the season, and increase the yield.
[Illustration: FIG. 200. THE DIFFERENCE IS DUE TO TILLAGE]
Corn is a crop that needs constant cultivation, and during the growing
season the soil should be stirred at least four times. This cultivation
is for three reasons:
1. To destroy weeds that would take plant food and water.
2. To provide a mulch of dry soil so as to prevent the evaporation of
moisture. The action of this mulch has already been explained.
3. Because "tillage is manure." Constant stirring of the soil allows the
air to circulate in it, provides a more effective mulch, and helps to
change unavailable plant food into the form that plants use.
Deep culture of corn is not advisable. The roots in their early stages
of growth are shallow feeders and spread widely only a few inches below
the surface. The cultivation that destroys or disturbs the roots injures
the plants and lessens the yield. We cultivate because of the three
reasons given above, and not to stir the soil about the roots or to
loosen it there.
[Illustration: FIG. 201.]
In many parts of the country the cornstalks are left standing in the
fields or are burned. This is a great mistake, for the stalks are worth
a good deal for feeding horses, cattle, and sheep. These stalks may
always be saved by the use of the husker and shredder. Corn after being
matured and cut can be put in shocks and left thus until dry enough to
run through the husker and shredder. This machine separates the corn
from the stalk and husks it. At the same time it shreds tops, leaves,
and butts into a food that is both nutritious and palatable to stock.
For the amount that animals will eat, almost as much feeding value is
obtained from corn stover treated in this way as from timothy hay. The
practice of not using the stalks is wasteful and is fast being
abandoned. The only reason that so much good food is being left to decay
in the field is because so many people have not fully learned the
feeding value of the stover.
=EXERCISE=
To show the effect of cultivation on the yield of corn, let the
pupils lay off five plats in some convenient field. Each plat need
consist of only two rows about twenty feet long. Treat each plat as
follows:
Plat 1. No cultivation: let weeds grow.
Plat 2. Mulch with straw.
Plat 3. Shallow cultivation: not deeper than two inches and at
least five times during the growing season.
Plat 4. Deep cultivation: at least four inches deep, so as to
injure and tear out some of the roots (this is a common method).
Plat 5. Root-pruning: ten inches from the stalk and six inches
deep, prune the roots with a long knife. Cultivate five times
during the season.
Observe plats during the summer, and at husking-time note results.
SECTION XXXIX. PEANUTS
This plant is rich in names, being known locally as "ground pea,"
"goober," "earthnut," and "pindar," as well as generally by the name of
"peanut." The peanut is a true legume, and, like other legumes, bears
nitrogen-gathering tubercles upon its roots. The fruit is not a real nut
but rather a kind of pea or bean, and develops from the blossom. After
the fall of the blossom the "spike," or flower-stalk, pushes its way
into the ground, where the nut develops. If unable to penetrate the soil
the nut dies.
In the United States, North and South Carolina, Virginia, and Tennessee
have the most favorable climates for peanut culture. Suitable climate
and soil, however, may be found from New Jersey to the Mississippi
valley. A high, porous, sandy loam is the most suitable. Stiffer soils,
which may in some cases yield larger crops than the loams, are yet not
so profitable, for stiff soils injure the color of the nut. Lime is a
necessity and must be supplied if the soil is deficient. Phosphoric acid
and potash are needed.
Greater care than is usually bestowed should be given to the selection
of the peanut seed. In addition to following the principles given in
Section XVIII, all musty, defective seeds must be avoided and all
frosted kernels must be rejected. Before it dries, the peanut seed is
easily injured by frost. The slightest frost on the vines, either before
or after the plants are dug, does much harm to the tender seed.
[Illustration: FIG. 202. A PEANUT PLANT]
In growing peanuts, thorough preparation of the soil is much better than
later cultivation. Destroy the crop of young weeds, but do not disturb
the peanut crop by late cultivation. Harvest before frost, and shock
high to keep the vines from the ground.
The average yield of peanuts in the United States is twenty-two bushels
an acre. In Tennessee the yield is twenty-nine bushels an acre, and in
North Carolina and Virginia it reaches thirty bushels an acre.