RVHNO WWW Ry MW ASS OAs eet eld pit ed WAN AK Yilld pebetee hia th “ie iy de Ye on ha ~ : A iy, Leh POI yyy yap Susy thy “ly os: Copyright NO. COPYRIGHT DEPOSIT. ALINNOM HLIIM ONV SSANdVT9 HLIM LVd SII SAAID II GNV "XTLSUNUVA GNVI AHL MOTd He a ORES Fr an 8 Aan pias 98 fe ie ig - SOILS Their Properties, Improvement, Management, and the Problems of Crop Growing and Crop Feeding By CHARLES WILLIAM BURKETT Director of the Agricultural Experiment Station, Kansas State Agricultural College Where grows ?—Where grows it not? If vain our toil, We ought to blame the culture, not the soil. Pore. ILLUSTRATED NEW YORK ORANGE JUDD COMPANY LONDON Krecan Pau, Trencu, Trupner & Co., LimitTep oF TLIBRARY of CONGRESS Two Covies Received SEP 6 1907 i Copyright Bntry J (3,190 CLASS TAY ‘XXc., NO. (SIVGS COPY 3. CopyRIGHT, 1907, BY ORANGE JUDD COMPANY All Rights Reserved [ENTERED AT STATIONERS’ HALL, LONDON, ENGLAND] ACKNOWLEDGMENTS The author is under obligations to many friends for helpful suggestions and illustrations. Especial credit is due the following for illustrations used on the pages indicated: Professor E. O. Fippin, of Cornell University, 29, 31, 34, 36, 65, 91, 94, 113, 173, 174, 1092, 195, 198, 204, 218, 230, 266, 280, 283, etc.; Professor A. M. Ten Eyck, of the Kansas Experiment Station, 2, 13, 20, 47, 197, 270; Professor Oscar Erf, of Kansas Experiment Station, 207, 209, 211, 250; Professor Charles E. Thorne, Director of the Ohio Experiment Station, 100, 105: Dr. C. G. Hopkins, of the Illinois Experiment Station, 268; George K. Helder, 177, 178, 180, 182, 183, 194, 202. Thanks are also due the Orange Judd Company for many photo- graphs and B. F. Williamson for the line drawings. CHAPTER I ike MITE IV. V. Val: VII. VIII. 1D.e xX. Dole XII. XT. XIV. XV. XVI. XVII. XVII, XIX. XX. XXI. XXII. XXIII. XXIV. XXV. XXVI. XXVIT. DOV IIT XXIX. XXX. CONTENTS Introduction ; The Soil Makers . : The Soils that Living Things Have Made What We Find in Soils ae Concerning the Texture of the Soil . How Plants Feed Meri The Elements that Plants Use How Plant Food is Preserved . ; Getting Acquainted with Plant Food . é The Potential Plant Food: Its Stores and Native The Role that Tillage Plays . Liming the Land: A Corrective for Aiding: The Quest of Nitrogen The Release of Soil Nitrogen: The Return: to the TS Nitrification: Nitrogen Made Ready for Plants . Reclaiming Lost Nitrogen: the Call to the Air Soil Inoculation: How Done Draining the Land 2 | yt Soil Water: How it is Lost; how it May be Held Dry Farming: A Problem in Water Conservation Tillage Tools: What They are for; how to Use Them The Cultivation of Crops: The Tools and Purposes Stable Manure: Its Composition and its Preservation Handling Manure on the Farm Buying Plant Food for the Soil . Using Chemical Manure Intelligently . Mixing Fertilizers at Home . Dairying: An Example in Soil Buildin Rotation’ of Cropsiysms cise ee The Old, Worn-out Soils: What we May do for Them Conclusion: A Bit of Philosophy . ee ic 108 117 124 132 143 152 164 176 185 197 206 216 227 238 246 255 266 282 291 ILLUSTRATIONS Only the Roots Remain Behind A Bit of Earth’s Clothing . : Gradually Changing from Rees to ‘Soil Cover Crop for the Orchard . A Field of Corn Carried pag a Raging Flood : Just after a Flood Soil Builders at Work . . Alfalfa Roots Go Deep into the Seite A Crop that is Hard on the Soil . Section of Soil Showing Air Spaces and Baracles : On Two Types of Soil . Crop Adaptation . A Case of Bad Rextute Taking Soil Samples The Pore-space of the Soil A Soil that Needs Humus Circulation of Water in the Soil . Vegetable Matter Aids the Soil in Holding Water : Trees in the Prairie Region . How Plant Food Gets into the Soil ; The Underside of a Leaf with a Microscope . Oats. . Cross-section of Root Hate Root Hairs . How the Sap Cartent Moves’ The Greater Part of this Wonderful Gp Games Gam the nee Getting Humus into the Soil . 5 Cotton Plant Above and Below the Ground 3 A Root Hair with Soil Attached . Making Plant Food Available . At Work in the Corn-field . Getting Ready for Cotton . Poor Grass, Poor Cattle PAGE Vill ILLUSTRATIONS Corn Growing in Surface and Subsoil . A Crop that Calls for Much Nitrogen. . A Crop that Gets Nitrogen from the Air . A Sure Way to Improve the Soil . Increasing the Nitrogen with Legumes Alfalfa Roots: Vegetable Tillage Tools A Good Job of Plowing . : Plowed for the First Time Effect of Plowing Wet Land . Limed and Unlimed Land . Using the Lime Spreader . A Magnificent Crop of Beans . Two Kinds of Bacteria Found in Decne Wemetabie ‘Matter Bacteria Usually Found in Decaying Organic Matter Some Bacteria that Cause the Fermentation of Urine Nitrifying Bacteria Losing Nitrogen and Tiana: : Root Tubercle Bacteria . . Back of Good Tiilage is the Well- bred ere Horse Some Legume Roots Showing Root Tubercles . Growing Bacteria in the Laboratory . P Alfalfa: the Best All-round Crop in Avnenied : Red Clover Roots aa Soil Temperature . : A Way to Help the Diainaee é Losing Soils by Heavy Rains . The Result when Water was Senured and Held’. Effect of Cultivation of Corn Crop . Cultivation Checks Evaporation . A Home-made Roller : Disking the Ground before Plows : A Stone Mulch ae A Good Mulch Kaffir Corn . : Corn Planted sith Disk Purrow -opener Avacned : Double Disking the Land ee “Out There in Kansas” Sub-surface Packing . Dry Land alice Z Ideal Plowing . Bh oe Furrow Slices that are foo “Flat Seeds ILLUSTRATIONS Plowing Levees for Rice . “ ‘ Everything is Done at One @paraven ; Where Rolling Does Little Good The Acme Harrow : : A Step in Soil Preparation . Corn Roots Cultivating the Orchard The Gentle Art of Cultivation Catalpa Tree with One Season’s Growth. Losing Water from Soil The Erf Stabling System . Losing Fertility A Covered Barnyard : Letting the Manure Get Away A Common Way but Poor Practice . Hauling Manure to the Field . Manure Spreader at Work Crimson Clover in the South . eer Cow-peas and Fertilizers and a Poor Soil . F A Case where All Three Elements Are Needed . Our Common Fertilizing Materials . Where Acid Phosphate Pays . A Muck Soil that Profitably Uses Botesunt Plant Food in a Bag of Fertilizer . The Bag and the Plant Food in It . : Fertilizers Pay Best when Good Plowing Has Heed Date ‘ The Soil that Tells Its Own Story . ; Where Alfalfa Prospers Dairying Prospers : Complete Irrigating System with Dairy House and Resende Attached A Balance Wheel in Bernie Two Kinds of Farming . Relative Amounts of Plant Food when a 7 Ten of Fach is Sold Crop Rotation . 4 Corn in Growing Stage . Corn at Harvest Time . Cow-pea Roots Crop of Corn and Cow-peas the Same Wear Close Rotation of Crops é Crop Rotation and Mixed Farnine Go mea in Haase Timothy May Go in Rotation . iy 3 ix 188 190 192 104 195 197 198 200 202 204 207 209 211 216 218 220 221 224 227 228 230 233 236 241 243 247 251 2560 259 260 262 263 266 267 268 270 272 278 277 280 x ILLUSTRATIONS In Perfect Condition . , What Humus Does in the ‘Soil . Grow Legumes Constantly . One Kind of Farming that Teaproves the bent 5 A Sure Way to Ruin the Farm . Seven of Our Leading Products . Intensive Farming : A Department of the Fann Factory : “Thro Wood and, Mead”. 9 = 283 285 288 291 203 295 296 298 299 THE PLOW By V. F. Boyson [By courtesy Everybody's Magazine.] I am a worker. Sleep on and take your rest Though my sharp coulter shows white in the dawn: Beating through wind and rain, Furrowing hill and plain Till twilight dims the west And I stand darkly against the night sky. I am a worker, I, the piow. I feed the peoples. Eagerly wait on me High-born and low-born, pale children of want: Kingdoms may rise and wane, War claim her tithe of slain, Hands are outstretched to me. Master of men am J, seeming a slave, I feed the peoples, I, the plow. I prove God’s word true— Toiling that earth may give Fruit men shall gather with songs in the sun. Where sleeps the hidden grain Corn-fields shall wave again; Showing that while men live Nor seed nor harvest time ever will cease. I prove God’s words true, I, the plow. INTRODUCTION THE EARTH’S CLOTHING It has been calculated that if the earth were tunneled direct to the other side, 7,918 miles would be traveled in making the journey. But a difficulty would be met in this endeavor: After going a few miles, the, heat would be so intense that further progress would be impossible. For as we descend into the earth, after going a very little way, the temperature rises at the rate of 1 degree for every 50 feet, a rate that is universal over the earth’s surface, and for the greatest depth attained. From the known laws of the conduction of heat the conclusion follows that at a depth of 15 to 20 miles below the surface the earth is red hot, while the heat 100 miles deeper, if applied at the surface, would liquefy all mate- rials at the surface crust. These known facts have led to an hypothesis that the interior of the earth is more or less fluid, and that the crust is only a thin shell floating on the molten globe. However, the earth as a body is very rigid and sub- jected to a pressure so great that despite the high tem- perature, the interior is locked into a solid mass as rigid as steel itself. But after all, we are concerned less with the interior of the earth and with the surface more. Our aim is to know the outer covering—the clothing that encloses this hidden interior—and to use its history to our profit and good. Every science has labored with the secret that is hidden in this clothing of the earth that the world might know some of the stories it has to tell: of the 2 INTRODUCTION strange forms of vegetation that once visited here; of the bizarre creatures that peopled it in old days—before man came and before the myriads of present-day friends and foes had sprung into existence; of the monsters that throve and multiplied and brought fear and death to weaker kind; of the hideous reptiles that crawled over the slimy domain, battling with each other or with the ONLY THE ROOTS REMAIN BEHIND This picture is an example of the power of water in soil making denizens of the forest; of primitive man—weak, dull, savage, and yet endowed with more cunning of brain— fulfilling his mission and preparing the way for better and higher tribes; of all the agencies that have been at work in the making of the garment that covers this great body; of the soil, the real covering, and all it means: these many stories have been told in rock and stone and INTRODUCTION 3 in slowly perishable materials, and so clearly told that man reads and reflects and profits in the lessons that are learned. And of some of these we want to learn in the pages that follow. The soil: the clothing of the earth.—The real cloth- ing of the earth is the soil—and we are to study it: the good, kind soil that brings us so many useful and beau- tiful and wholesome things. For with the soil is the real beginning of all material things, of all things of worth; of all things that secure contentment; of all things that lead to comfort and happiness; of all things that have to do with food and raiment and shelter; of all things that advance mankind and promote civilization. All of these things spring from the soil—from the simple, inanimate, material thing we call dirt. The earth’s clothing includes the soil in all its varia- tions; includes the dirt in which plants root and feed and grow; includes the rock and stony structures of sea and mountain; includes the waters of the soil and of the deep; includes the minerals in the mines that man seeks, often losing his life in the search; includes the insect, the worm, the bacterium, and every form of life that labors for its usefulness and grandeur; includes the fruits of field and soil—the life that grows therein and makes food for man and beast; includes the tree that grows and fructifies in forest or orchard; includes the cultivated crop of every variety and species, of every form and description; includes every vegetable type that provides raiment, or covering in the open, or when re- moved from its place of growth, becomes house and shelter that protects and guards and comforts; includes everything that has use and that supplies a want in every part of the world and for every purpose. All these things come from the soil, from the magnificent garment 4 INTRODUCTION that clothes the earth. “Before literature existed, before governments were known, agriculture was the calling of man. And all the fruits of social progress since then grew from the brown soil.” The soil changes its clothing—The clothing of the earth is a changing one. It is of as many colors as the coat of Joseph. And this clothing changes not in color only, but in texture, in wearing ability, in usefulness. For are there not many soils that had poverty as their inheritance and still others that had only the fullest riches? Yet both kinds meet at a common point so often—the rich have become poor, the poor have become rich. All over our land this change is observed. To man’s credit, however, we are now at a point in farming where this may be corrected, for we realize that the soil is capable of change and of improvement: it offers a great opportunity for thought and study. Applied here, knowl- edge brings abundant returns. The soil and the subsoil.—There are two layers of this clothing: the soil and the subsoil, and of course we must give due weight to both with any discussion of crop pro- duction or in any method of land management. In both soil and subsoil are found organic and inorganic mate- rials, although the subsoil contains a greater portion of the latter substances than the soil immediately over it. It isin both of these layers that the roots of plants grow, and now that we know more about roots than we did a few years ago, we ought to be able to handle lands with greater certainty and to grow crops with more profit. We know where roots grow; we know the places in which they feed and just how they do their work. Is this not a practical turn? Roots grow from their tips, and at these points they gather food and drink. With the passing of INTRODUCTION 5 a little time the tip end is sent further on in the search; it grows longer; it finds a new place to take nourishment. The roots grow on and on and new root hairs form, taking their nutriment from the new and fresh pastures. So all about in the soil they go, just below the surface, a little deeper in the soil top; even in the subsoil (if they can enter it), and all the while they search and seek for plant food that the great body above may be supplied. Fertility is more than soil—And we should bear in mind that fertility is more than a mere abundance of plant food in the soil (we have learned more about the soil). Fertility is plant food, of course, but in part, only. It is water—just the right amount and served when needed. It is climate—neither too cold nor too hot for the particular plant. It is texture—soil grains of proper’ size and in proper relation to control heat, moisture, and air. It is humus—a goodly amount to supply nitrogen as required, and to help in making pleasant and comfort- able the home of the roots. It is tiilage—the real, true sort of tillage that provides tilth and mellowness. It is A BIT OF THE EARTH’S CLOTHING 6 INTRODUCTION the plant—the right kind for the particular soil. Fer- tility is these and all other requirements that secure a soil environment to the liking of the growing plant. Hence, the plant food of the soil is an incident, but a necessary incident, just as heat and air and water and tillage and texture are incidents and prerequisites of high production. Ssolls CHAPTER 1 THE SOIL MAKERS Do not think, gentle reader, that I am going to weary you with a long discussion about the history of the ground. The only misgivings the author has had in the preparation of this volume has been the necessity of say- ing these few words that follow about the soil makers, the agencies that have been at work making the soil. Important? Yes, in a way; but if you see the matter as I do, you are more interested in having the soil dem- onstrate what it can do now, rather than to inquire into its line of descent; to be familiar with its ability to do work and to perform to-day, rather than to know its ancestral life of long years ago. First effort in soil making.—To find the first effort in soil making we shall have to go back to a time far into the past; back before man had appeared; farther back yet than the time when plants had begun their existence. For is it not true that plants must have raiment for their roots—earth in which they may grow and out of which they may get food and drink? We shall have to go back—very far back in the past— when the surface was cooling and forming its crust, when the entire surface of the earth was rock—no ani- mals, no cultivated crops, no trees, no grass—not even the tiniest form: of bug or plant or beast. For at this time the earth was void and without form, 8 SOILS although surrounded by an atmosphere of mist and vapor. When this rocky and molten mass of earth began to cool, its crust became broken and uneven. But no soil was there, only hard, fire-burned rock. Then centuries passed—thousands and thousands of them. The molten mass had cooled. The darkness that was on the face of the deep gave way to light and change. For: the light came from the sun and these rays the rocks absorbed. They felt the refining influence, also, of the air as it played over the wrinkled faces of rock and cliff. At first these two agencies made but little, if any, impression. So hard was the rock, what might air and sunshine do? GRADUALLY CHANGING FROM ROCK TO SOIL But busy bodies, that are at work always and ever, gradu- ally gain their ends, and so these first rocks, now cold, now warm but yet so hard and strong—and so brutal— slowly gave up their determined tenacity and lost some of their strength and hidden power. A little softening, and they were changed, just as the refining influence of good air and much sunshine refines the plant or beast or man that comes under their spell and change. THE SOIL MAKERS 9 How the atmosphere assists.—Just as soon as the first rocks were exposed to the weather, remarkable changes then resulted. The rocks, after long exposure, crumbled somewhat; just a few particles, a few tiny grains from: time to time fell apart from the whole and dropped to a lower level to be carried away by water; or they were picked up and carried away by the wind when it rose in sufficient force to defy the mighty giants of rock forma- tion. Of course the wind accomplished but little with each attack. But the wind is ever young; it never grows old, and a thousand years of trial weaken it not. These tiny particles—the first released from rock—represent the beginnings in soil making. And ever since the time, who shall say how long? that these first particles were given to the wind, the weather has been at work making soil. The atmosphere assists in soil making because of the chemical action of the gases that compose the air and of the moisture or vapor it holds. The two important gases that are so powerful in making soil are oxygen and car- bonic acid. They are always at work; they have been at work from the very beginning of time; and so long as life exists, from the tiniest plant up to the finest devel- oped type of man, oxygen will be required for the work of the world. Oxygen forms oxides by combining with nearly all sorts of materials that are found in the earth. You know how quickly iron rusts when exposed to the air, especially if moist—an oxide of iron has resulted; not that the iron has been destroyed nor the oxygen of the air that com- bined with it, but the two have united and formed a new chemical compound, powdery in texture and now in a form to be easily combined with acid so as to become food which plants may use. IO SOILS The carbonic acid of the air serves its part, also, but in another way. It works with water and in this manner: the two substances—carbonic acid and water—readily commingle and produce a liquid that is strong as a sol- vent, effective as a dissolving agent, so as to weaken the rocks, and active as a selective power which seeks the soft minerals of earthy formations and quarries them for plant builders to use. Oxygen and carbonic acid work whether man would have them or not; they ask not his permit when they shall work nor where; and neither do they ask on what materials they shall satisfy their desires. They work for Nature and to her they belong, and in this case they re- fuse to bow or to conform to man’s wishes. But air and water are usually most effective as soil makers when they are working together, for they accom- plish more and do it more quickly. You have seen per- haps some iron tool that for years has remained in the bottom of a well, the water having made no perceptible headway against it. Because no air was there, rust did not result. And again, you have seen another iron tool kept in an atmosphere that was dry. You note no per- ceptible disintegration because moisture is highly essen- tial for iron to change into its own powdery dust. In dry climates rocks last longer than in moist climates for the reasons explained in reference to the dissolving action of air, carbonic acid, and moisture. Changes in temperature play a part—In the early days the earth had a larger garment to clothe it than it now possesses. It was very hot—a boiling mass, at first. As time went on, the outer crust became cool, and at the same time this crust hardened and became fixed in char- acter, but only temporarily; only long enough for the cooled crust to deepen its thickness, when the entire body THE SOIL MAKERS vu must contract; because, you know all matter expands when heated and becomes smaller when cooled. With the cooling of the earth its outer clothing was drawn in, with the result that it was wrinkled—hills here and high mountains there—which continued so long as the con- tractive force was greater than the holding force of the crust. In all this work changes were taking place. Huge beds of rock were thrown up and exposed in an hundred places to air and moisture, where before they were so snugly covered that neither could enter. The earth continued to cool and in some places ice formed. Vapor condensed and dropped as rain. For cen- turies rain had fallen, but as it struck the hard earth it was flung back into the air again as vapor and mist. As the earth gradually cooled, water was thrown back with less vengeance and force. Some of it was left for a consider- able time on the earth, where it had collected in basins, or in crevices in the rock. It was caught here at times by wind-storms that were cold enough to freeze this gathered water. As the water froze, it expanded, forcing many crevices wider, breaking many rocks asunder—and doing what we are pleased to call its share in soil making. It is this change in temperature that assists in soil making—that weakens the original rocks that were ages ago forced from the very bowels of the earth. Rocks such as the granite type—whenalternately heated and cooled for a long time—gradually weaken and break. Sudden changes in temperature produce similar results. Temperature is more active when moisture is present. Even in the modern world we see stone buildings, that frequently drop a corner or a slab, due to sudden freezing when saturated with water. You recall with what ease the same may be done with a hammer on a cold day. Since nearly all rocks, even those deeply imbedded in 12 SOILS the soil, contain not a smail amount of water, cold be- comes a most potent as well as a most active agent in breaking and pulverizing them and in preparing them for the soil itself. Water wears away the rock.—But water is a soil maker in another way than as a solvent. By simple fric- tion it wears the hardest rock and makes for itself a track in which it may flow with greater ease. This action of the water has been so constant, and so regular, through so many summers and winters, and at work for so many, many centuries, that it has widened and deepened its COVER CROP FOR THE ORCHARD Oats are used here, and do good service for protection against water and wind channels in all parts of the earth so that millions and millions of tons of solid rock have been washed from higher to lower levels, the dissolved part being left in lower regions or carried out into the sea, where the ac- cumulations for centuries have made new lands, some of which are now and for long times have been used for the growing of many of the necessities of man. Every time you see moving water in a stream, you see a soil maker at work. With even a light shower the water deepens its color, since the stream, the road and the field THE SOIL MAKERS 13 give up their finest dust, and send real soil downward to a lower level. It is beyond our power to estimate the enor- mous quantity of soil that is moved during a single year. A single illustration will show how great this quantity is: The Mississippi River as it pours into the Gulf of Mexico each year deposits soil sufficient in quantity to cover an area of 100 square miles nearly three feet in depth. Add to this the outpourings of all river systems and you have land areas made each year that equal many a state in size. Whenever a river outflows its banks it leaves deposited on the submerged territory tons and tons of mud—and this mud is valuable soil—often as much as an inch in thickness. In all mountainous regions we have the results of the wearing power of water. Huge cafions, hundreds of feet deep—the Colorado Cajion is 2,000 feet in depth—mark the track of the leaps and pourings of water from the mountain summits. When considered in the aggregate, the amount of soil made by water-washing of our thou- A FIELD OF CORN CARRIED AWAY BY A RAGING FLOOD 14 SOILS sands of hills and mountains is large. Here we see a mighty force and a powerful agent at work in soil making. The sorting power of water.—In this connection we should not forget the work of water as it moves silt, clay, pebbles, and stone that have been caught in its channels and then moved downward toward its emptyings. Silt and clay are readily held in suspension even if the water is slow going. It requires rapid currents to move the heavier, coarser stones and pebbles. As these are carried along, their rough edges are worn off, their sides are scraped and scratched, and many particles are pulverized and ground—all contributing to soil making. To be sure, this soil will be deposited in lower regions, yet it is now soil, the same as that in the cultivated field or garden. The rdle that ice has played.—In the northern part of the United States we have a class of soils formed by giant masses of ice called glaciers, that moved in a southward course many, many centuries ago. Our ideas of the cause of this vast body of moving ice are not clear and we have only the evidence that once it was so. We are told that all the northern part of our country was covered with a frozen mass of ice and snow, and that for some reason this whole mass assumed a moving character, creeping over plain and streain, attacking every hill top and mountain range, and without further ado, conquering them as if play mounds made by children’s hands were the confront- ing power. As this huge mass moved onward in its course it gathered up huge rocks that once were free, quarried other giants from the bosoms of the mountains, and played with them as it went along—rolling them, forcing them together, dragging them, rubbing their rough faces until they were smooth (if perchance they were not com- pletely ground into powder)—until finally the rays of the THE SOIL MAKERS 15 more southern sun robbed the glacier of its power by melting snow and ice, which freed, rushed on into river channels to be lost at last in the seas of the East and the South. Soils that were formed by this moving mass of ice are known as drift soils. Such soils vary greatly in composi- tion and in physical nature. The area formed by these glacier or drift soils is altogether lacking in uniformity, its surface is broken often abrupt, its elevation is some- times considerable, often but slight and its producing power is modified by the nature of the deposits. While it is true that these soils are fairly well supplied with necessary mineral constituents essential to plant growth JUST AFTER A FLOOD they are often deficient in organic matter—the source of nitrogen supply. Wind made soils.—While the wind is often most vigor- ous in its activity, it is a reasonably slow agent in soil making, when considered by its daily work; it must be studied only in its aggregate in respect to all the geolog- 16 SOILS ical ages past. You will find the wind most actively at work in arid regions and in those sections where sand and dust most abound. A single experience in a wind storm must convince you of the power as well as of the quantity of earth that is moved throughout the world. Dust or particles of the earth are in the air at all times, and with every drop of rain, every flake of snow, and every movement in the air these particles are carried elsewhere than to the spot at which they were originally gathered up. You will find in some sections of our country huge mounds or drifts of sand that have been deposited by the constant and more vigorous action of the wind. CHAPTER: I] THE SOILS THAT LIVING THINGS HAVE MADE No one knows just when the first, plant came into the world, nor the kind: it was too far back in the dim ages of the past; long before any history was ever written; long even before man or bird or beast had yet appeared. We may be sure, however, that it was a very tiny plant, so small that the little roots did not need to go deep into the earth, for the soil was just beginning its growth. We may be safe even in saying that these early forms of plants had only the rock itself for their homes, and on this rock they established themselves, sending their small roots just the tiniest bit into the crevices and into the opened particles that had been loosed by air and water, by heat and cold. The beginning of plant growth.—But aaanilee 3s the earliest forms of plant life were aquatic in character: they lived in the water. We have learned of the solvent power of water. Many of the early stagnant pools became de- positories of water holding in solution the dissolved min- eral materials of the kind forming the rock structures. This was just the sort of food that these pioneer plants fancied, for they and all of their kind since have secured their feeding materials in this manner. As years and cen- turies passed, these beginning forms of plant life became stronger, more steady and some became quite venture- some, clinging to the rocks that held fast the waters of the pool; and still others, flinging the experience of their parental tribes to the winds, ascended beyond the limits 18 SOILS of the pond, where flowing water was uncommon, there to become adjusted to their new homes and to their new environment—at last to be stationary in their rules of living. It is likely the first stationary forms found lodgment in the crevices of the rock, where perhaps had accumulated small quantities of soil that had been made long before by air and water working in unison. These plants, no doubt, set their fibrous roots firmly against the rock sur- faces and worked in their own way in securing the coveted elements locked in the storehouse of the rocks. Just as the ivy of to-day creeps over stone and brick, so did these first forms secure their food substances for their life and growth. But with this difference: those were small, insignificant plants and of low order; the ivy has culture, good breeding and pedigree as its inheritance. Real soil was made and left—You must not think SOIL BUILDERS AT WORK Leaves, roots stems and grass find their way back to the soil and enrich it THE SOILS THAT LIVING THINGS HAVE MADE 19 these pioneer plants lived forever. They grew old in time: they died. But at their death they left a valuable contribution to the world. They left the riches they had accumulated: the elements they had secured from the rocks, the substances of their growth, the wee beds of soil they had secured from their forefathers, from the donations of the wind, and from the gifts of air and moisture. With this wealth available, there was no longer so great a struggle. The decayed plant life in the crevices and the deteriorated rock afforded better feeding grounds for plants, more soil for support, more food for the needs of maintenance and of growth. Consequently, this better- ing of material necessities afforded increased opportuni- ties for growth. A higher order of plants might now come. So the small struggling plants, through a long course of years, changed, now gradually, now suddenly, into stronger varieties and species—onward and upward in the scale, until the time when soil was present in abundance, when the higher plants, useful for food and raiment, might be secure and safe, thoroughly fitted and abundantly adapted to all the environmental conditions needed for their complete development and growth. The work of plants in soil building.—It follows, then, that every kind of plant is a soil builder. The decay of the plant at once produces a change in the texture of the soil-making material. It is this addition of the organic matter—the dead plant—that produces this constantly performed miracle: for as the plant decays in the soil, the particles of soil in contact with it likewise decay. In other words, soil rotting is soil making. Decay of any material in the soil—organic or not—favors and induces the breaking down of the various complex compounds forming the rock, or the raw or the untamed soils. 20 SOILS The addition of vegetable matter to the soil has assisted in soil making from the time that plants came first to the planet; it has increased the efficiency of all other agencies ever since the early days; and at the very present time it is the soil builder’s best friend,—its decay is essential to the feeding of plants. The roots of plants have done their work in soil making. A great work it has been! For they have gone down deep into the soil making tiny channels for air and water; creeping into the crevices of rocks, they have continued their growth and their enlargement, in the end, breaking ; we many rocks asunder, dis- lodging others from their beds,—exposing all to the disintegrating influences of air and moisture, of heat and cold. And_ roots — especially the small, fibrous ones— have a solvent action as well. The juice they exude at the tips, and the moisture with which they surround themselves, work a change in the soil particles between which they grow; limestone or granite or feldspar or mica slowly but surely suc- cumbs to the deteriorating action of root life. Animals the modern soil makers.—Soil making ALFALFA ROOTS GO DEEP INTO was considerably THE SOIL SS ee PRR IEE AS. - oe: THE SOILS THAT LIVING THINGS HAVE MADE 21 advanced when animals first made their appearance. But animals of all sorts have been potent workers in soil making, the higher animals largely by the manurial re- turn to the land and the lower forms through the manurial effect, but also in directly affecting the physical conforma- tion of earth. For does not the ant seek the earth for its home and shelter, to construct there its house of many rooms, with the many tunnels connecting the dwellings of the nation? What are these homes and these tunnels but underground traps for air and moisture—soil builders? Besides the work done in this direction, a tremendous quantity of earth is annually turned over and exposed to sunshine and rain, to heat and cold, to every influence concerned with soil making and soil improvement. Every sort of insect or animal that burrows into the soil, that opens it, or tunnels it, or loosens it, contributes not a little to soil making: the ant that builds there, the mole that tunnels, the prairie dog or hedgehog that bur- rows, the earthworm that glides and crawls, and even eats and digests—all are man’s good friends in having had a hand in preparing the surface of the earth for the luxuri- ant growth of vegetable life. The task of the earthworm.—The task that has been the earthworm’s is a most important one. So simple are these creatures, so faithful are they in their labors, so undemonstrative in their duties, we scarcely give them a thought save the time when we seek them for bait for our fishing traps. But the earthworm has for ages been busy opening the soil to air and water, and even more: it eats the raw soil underground and plows its way upwards and downwards, casting at the surface the unused por- tions of its eatings. In doing this, the muscular gizzard of the worm is ever busy rubbing and grinding stony 22 SOILS particles, mixing with these the organic matter taken into the body system; with these go the secreted slime that has a dissolving effect—useful in making subsoil and un- tamed earthy constituents available as food for plants. As proof of the great goodof these indefatigable workers, we have the evidence of Charles Darwin, who after long study and observation declared that in many parts of England as much as ten tons a day of dry earth annually were passed through the bodies of these common worms of the field. He also calculated that as much as ten inches of the upper surface of the soil passed through their bodies every fifty years. You can gather from this evi- dence what worthy workers these insignificant animals have been in preparing the earth for the habitation of man. ‘The increased production of all products of the garden, of the orchard, and of the field has been due, in not a small measure, to these underground helpers and to these wonderful workers in soil making. CHAPTER It WHAT WE FIND IN SOILS Having come now to the point where soils are made, we may with all propriety consider their physical nature, and then the treasures they hold fast secured in their earthy storehouses. Not that soil making has ended, for this process goes on forever. Only this: a time has been reached in their development when, with the aid of tillage tools, the most productive and useful of plants might now be grown for the highest profit of man. Let us go out into the field itself. Of what is this soil made? was at one time the first inquiry. Naturally, it was said that soils were derived from the original rock formations. We have discussed already the agencies that have made our soils. No single one is responsible for yours or mine. That we possess these soils, there is no doubt. What brought them to us, what placed particular soils within the limits of our possessions, what influence or agency made them rough or level, good producing or poor producing, is not the problem now. Four kinds of soil materials——Our present inquiry is in reference to their physical conformation, to their com- ponent parts, to the minerals composing them. These ma- terials are: sand, silt, clay, and humus or organic matter. All productive soils contain these materials, but not in the same proportions. There is a wide difference in the quantities of each in our many varieties of soil. A pre- ponderance of one of these materials over the normal 24 SOILS average gives rise to a grade distinguished by the name of the material there present in excess of that normal aver- age. Hence, we get names that stand for the particular type, as sand soils, where much sand is present; clay soils, where much clay or silt is present; and humus soils, where much organic matter is present. Plants show preference for certain soils——And there is a very great problem unfolded here, for the most of our field crops do not do equally well on each of these soil types. Nota little partiality is shown. While some crops are not so very choice of their soil homes, others are par- A CROP THAT IS HARD ON THE SOIL Tobacco is usually a profitable crop, but one that quickly exhausts the soil of its fertility ticularly mindful; in fact, some, like the grape or tobacco plant, permit their fancy to extend even as far as the manufactured product. Size of soil particles.—It is due to the size of the parti- cles of which soils are made that we have our various classes of sand and silt and clay—rock descendants. When these particles are separated mechanically, we find WHAT WE FIND IN SOILS 25 that they can be classified into various groups, as follows: fine gravel, coarse sand, medium sand, fine sand, very fine sand, silt, fine silt and clay. To these components let us add humus, moisture, the sol- uble plant food elements, and we shall have the soils of our fields. The size of these particles and their mechanical ar- rangement have much to do in way of influencing soil productivity, of influencing heat, moisture, and plant food factors, of governing the type of soil that each crop fancies. Thus it is that a sand soil—where the coarser particles predominate—is a most favorable medium when reénforced with humus, in which certain crops, like the vegetables, are most at home. On the other hand, you will find the opposite extreme—where the finest soil grains predominate—most favorable to wheat and grass. In the first case—the sand type—water is freely received and as freely given to the subsoil, while with the clay type water enters with difficulty but remains longer with its host. Between these extremes we find all sorts of modified types: light sand loams, sand _ loams, loams, clay loams, and heavy clay loams. We should add, also, humus to these combinations, for it must be understood that humus is positively a necessity for remuncrative crops, regardless of type or of ancestry. What mechanical analysis shows.—To illustrate this point, let us take the mechanical analysis of barren sand soils: examples of the sand type that are found in many sections of the country—along the seashore, in the sand hills of the arid West, and throughout the desert regions. Using the plan now generally approved by soil investi- gators, we get the following—the average of 11 barren sand soils: 26 SOILS BARREN SAND SOILS Material Per cent Organic. Matters, A:-c cee ee eee eee 3.75 Kine) (Gravel, 2-1 =ninld <0. Cae eee CET ae ee 1.40 (Coarse Sarid, T= mit... see ee ee one ee 27.92 Medium,Sand:.5-;25 "mim. soceeeeee cio ae nena 31.64 Fine Sand; :25-:0-ameil... ve cae eae oe nn oe ee ee 17.48 Nery Fine Sarid, 1-05. anion eae eee 12.66 Silt.05 (OL pratt eraeactsen Gee er ee eee ee 1.90 Pine Silt, xOrGos imtiny <4 clave deca icine oe ee 0.86 Clays sO052.G00L MINUS «05, 5 ences Bross See eee ae ee ee ite Wit The above percentages tell their own story: they show the classes in which these soil particles fall. In other words, as much as 84 percent.ofthese barren soils is com- posed of sand. You can note readily the small percentage of silt, humus, and the clay- components. Were plant food to be added, it would be lost as quickly as the water that falls as rain. Soils containing so high a per- centage of sand may be used for a limited number of crops, and then only when reénforced with or- ganic matter, chemical fertilizers, and water at frequent intervals (by irrigation, if possible). What special soil types show.— To develop this idea further, let us take the analyses of a few soils SECTION OF THE SOIL F SHOWING AIR SPACES where certain standard crops grow AND ESRC to their fullest perfection, not for a single year, but for a time of sufficient duration to give these soils the right to the name of model examples of their type or class. WHAT WE FIND IN SOILS 27 MECHANICAL ANALYSES* OF TYPICAL AGRICULTURAL SOILS. Bright | Heavy : Wheat é ais | Material Corn | gojj | Grass | Truck Pea To- To- bacco | bacco Fine Gravel, 2-1 mm..... 0.00 0.00 0.00 0,00 0.00 3-09 1.12 Coarse Sand, 1-5 mm....] 0.15 0.23 0.08 0.30 0.00 7.16 1.82 Medium Sand, .5-.25 PURITAN ieein