Agriculture for Beginners.
by Charles William Burkett and Frank Lincoln Stevens and Daniel Harvey Hill.
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 a.s.sured 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 apt.i.tudes 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. Ma.s.sey, 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.
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 embarra.s.sed in mastering and heartily instructing a cla.s.s 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 cooperate 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 cla.s.s 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 gra.s.s, 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 ma.s.s. 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 sh.e.l.l 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 pa.s.s 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 quant.i.ties 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.
[Ill.u.s.tration: FIG. 1. ROCK MARKED BY THE Sc.r.a.pING 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 ma.s.ses 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 ma.s.ses. By and by some change of climate caused the ma.s.ses of ice to break up somewhat and to move south and west. These moving ma.s.ses, 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 acc.u.mulating 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_.
[Ill.u.s.tration: 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.
[Ill.u.s.tration: 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.