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Soil Fertility and Permanent Agriculture

Introduction

     It is the first business of every farmer to reduce the fertility of the soil, by removing the largest crops of which the soil is capable; but ultimate failure results for the landowner unless provision is made for restoring and maintaining productiveness.  Every landowner should adopt for his land a system of farming that is permanent,--a system under which the land becomes better rather than poorer.

     If the independent farmer is to adopt and maintain permanent systems of profitable agriculture, he cannot accept "parrot" instruction; he must know the why and wherefore, the reason for doing things, and the ultimate effect of his agricultural practice upon the productive power of the land.  Every farm is an independent enterprise in which the farmer himself is the superintendent and general manager, and he must be able to direct the business, even though he may be the only man to execute his own plans.  The agriculture of a state cannot be managed from a central office.  The landowner must think for the land.

     The author is familiar with the often expressed idea that what the farmer wants is a simple statement of facts, but he is even more familiar with the absolute truth that what the farmer demands is the most positive proof of the correctness of such statement before he is willing to make any change from a practice based upon long experience.

     In the preparation of this book free use has been made of such technical terms as are necessary to the discussion of fundamental principles with scientific correctness.  No apology is offered for this.  Farmers and agricultural students have at least as good intellects as other classes of people; and if when they leave the farm they can learn to understand and manage successfully such lines of business as banking, contracting, building, operating railroads, factories, and other commercial establishments,--

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xviii     Introduction

which they are doing everywhere,--they can also understand their own business, if they will, when they remain on the farm or in control of land.

     Technical books are to be studied; they are not written for entertainment.  They furnish definite facts, accurate data, and necessary information, relating to underlying principles upon which permanent successful practice must be based.

     The most important material problem of the United States is to maintain the fertility of the soil, and no extensive agricultural country has ever solved this problem.  The frequent periods of famine and starvation in the great agricultural countries of China, India, and Russia, and the depleted lands and abandoned farms of our own eastern United States are facts that serve as a constant proof that the common practice of agriculture reduces the productive power of land.

     The rule is almost universal that old land is less productive than new land.  This simple and well-recognized fact points inevitably toward future poverty, not only for the individual or the family, but likewise for the commonwealth and for the nation.  We may ignore this if we choose in America for a few more years, but with the decreasing productive power of our lands and with a rapidly increasing population the truth must strike us in the face in the near future.

     We cannot afford to let ignorance, prejudice, or bigotry blind us in this matter, neither in ourselves nor in others.  Even the confident assurance, by those who live in continued plenty, that the people of earth are not destined to suffer hunger, does not remove the positive fact that thousands,and sometimes millions, of people actually die of starvation within a single year in some of the old agricultural countries.

     An early recognition of these world-wide conditions and tendencies is of paramount importance to the people controlling the more productive lands of the united States, not only for their own sake, but also for the sake of others who are dependent upon those lands for their present and future support, whether engaged directly in agricultural pursuits or in other industrial or professional lines, which cannot exist and prosper without agriculture.

     If the art of agriculture has ruined land, the science of agricul-

Introduction     xix

ture must restore it; and the restoration must begin while some farmers are still prosperous, for poverty-stricken people are at once helpless and soon ignorant.  Outside help will always be required to redeem impoverished soils, for poverty makes no investments, and some initial investment is always required for soil improvement.

     It is the purpose of this book to teach the science of soil fertility and permanent agriculture, chiefly by reporting facts rather than by offering theories; and any one of common sense who reads the English language, and who can understand the common school arithmetic, can understand this book if he will study it.  (The fact may well be recognized that some who have ample time for study, though physically industrious, are mentally lazy.1)

     The author suggests, however, that the busy farmer, who wishes to familiarize himself as quickly as possible with the most essential practical facts pertaining to the economical and permanent improvement of common or normal soils, and who is willing to pass over temporarily the discussion of foundation principles, may well begin the study of this book with "Systems of Permanent Agriculture," Part II, after first making the following facts a part of his ever ready knowledge:

     (1)  Phosphorus and decaying organic matter are the two substances which constitute the key to profitable systems of permanent agriculture on most of the normal soils of America; although, when soils become sour, or acid, ground natural limestone should also be regularly applied, at the rate of about two tons per acre every four to six years.

     (2)  There are six essential positive factors in crop production:  the seed, a home for the plant, the food of which the plant is made (and this factor is just as important for plants as it is for animals), moisture, heat, and light.  Of these six factors, the least appreciated and the most neglected is that of plant food, and yet this is a factor which the farmer can very largely control, whereas the others (except the seed) are largely beyond his control.  (An important negative factor is protection from weeds, insects, and disease.)

     1 "Many poor farmers have a lazy faith in the Lord; they think or hope that He will somehow make up for whatever they fail to do."--Hoard.

xx     Introduction

     (3)  Of the ten different chemical elements absolutely required for the growth of every agricultural plant, three come directly from air and water in practically unlimited amounts, and these three (carbon and oxygen from air and hydrogen from water) constitute about 95 per cent of the common mature crops.  Nevertheless, each one of the seven elements obtained from the soil, though aggregating only 5 per cent, is absolutely necessary to the life and full development of the plant.  Indeed, if any one of these elements be entirely lacking, the soil would be infertile and barren.  So important are these plant-food elements, that soils are found so deficient in some essential plant food that the addition of a single element will more than double the crop yield.

     (4)  The five elements, potassium, magnesium, calcium, iron, and sulfur, are contained in most normal soils in such large amounts, compared to the requirements of crops, that the supply rarely becomes depleted.  Thus, in most cases, the problem is narrowed to the two elements, nitrogen and phosphorus, although, for various reasons, potassium also has come to have a recognized money value in commercial fertilizers.

     (5)  Nitrogen is contained in the air in inexhaustible amount, but the legumes (clover, alfalfa, peas, beans, etc.) are the only agricultural plants which have power to utilize the free nitrogen of the air.  Nitrogen in limited amount is contained in the soil in the organic matter, the principal material which gives a good soil its dark color.  If the supply of organic matter is maintained, by plowing under farm manure, clover, cowpeas, or other green manures, then the supply of nitrogen will also be maintained.

     (6)  The plowed soil of an acre (2 million pounds, for a depth of 6 2/3 inches) of rich, well-balanced normal land in the Corn Belt contains about 8000 pounds of nitrogen, 2000 pounds of phosphorus, 35,000 pounds of potassium, and 15 tons of calcium carbonate (limestone).

     (7)  The surface soils of the United States vary in composition:  (a) in nitrogen content, from 1000 pounds to 35,000 pounds; (b) in phosphorus content, from 160 pounds to 15,000 pounds; (c) in potassium content from 3000 pounds to 60,000 pounds, per acre; and many soils not only contain no lime, but are markedly acid and thus require heavy applications of lime, while some pro-

Introduction     xxi

ductive soils contain as much as 20 per cent of calcium carbonate, corresponding to 200 tons of limestone per acre.

     (8)  A 100-bushel crop of corn takes from the soil about 100 pounds of nitrogen, 17 pounds of phosphorus, and 19 pounds of potassium, in the grain, and about 48, 6, and 52 pounds of these respective elements in the stalks or stover.

     (9)  One ton of average fresh farm manure contains about 10 pounds of nitrogen, 2 pounds of phosphorus, and 8 pounds of potassium; and 100 pounds of the most common "complete" commercial fertilizer contains about 2 pounds of nitrogen, 4 pounds of phosphorus, and 2 pounds of potassium.

     (10)  One ton of clover hay contains about 40 pounds of nitrogen, 5 pounds of phosphorus, and 30 pounds of potassium.  When grown on soil of fair productive capacity, the roots and stubble of the clover plant contain no more nitrogen than the soil has furnished to the plant; but for each ton of clover plowed under, the soil is enriched by about 40 pounds of nitrogen.

     (11)  Roughly estimated, the plant food liberated from an average soil during an average season with average farming is equivalent to about 2 per cent of the nitrogen, 1 per cent of the phosphorus, and 1/4 of 1 per cent of the potassium, contained in the surface stratum (about 6 2/3 acre inches, or 2 million pounds of average soil).

     (12)  As an average in live-stock farming, the animals retain about one fourth of the nitrogen and phosphorus and destroy two thirds of the organic matter of the food consumed, and large loss is likely to occur in the manure produced, especially in nitrogen and organic matter, a loss of one half of these constituents being easily possible during three or four months, in part from fermentation, which may occur even under cover, and in part from leaching where the manure is exposed to the weather or where too little absorbent bedding is used.

     (13)  It is less difficult to maintain or increase the organic matter of the soil by means of legume crops and crop residues in a good rotation for grain farming than in any system of live-stock farming which does not include the purchase of feed.

     (14)  Some satisfactory rotation plans for grain farmers are wheat, corn, oats, and clover; or wheat, corn, and cowpeas; or

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cotton, corn, and oats and cowpeas.  The first of these is a four-year rotation which should include a catch crop of clover seeded the first year and plowed under for corn as late as practicable in the spring of the second year.  The other two are three-year rotations, and they should also include legume catch crops wherever practicable.  In each rotation for grain farming, all products are to be returned to the soil excepting the grain, or seed, and the cotton lint.  Either the whole cotton seed or the hulls and meal should also be returned for fertilizer.

     (15)  In live-stock farming the feeding should be done on the fields so far as practicable, and manure produced in the barn should be hauled and spread in the fresh condition so far as possible.  Sufficient bedding should be used to absorb all of the liquid excrement, which is as valuable, ton for ton, as the solid excrement.

     (16)  To insure the maintenance of the phosphorus content of the soil where large crops are produced, about 20 pounds of phosphorus per acre for each year in the rotation should be applied in grain farming and about 10 pounds per acre in live-stock farming (aside from that returned in the manure).  To enrich the soil in phosphorus, heavier applications should be made for a time.

     (17)  The average investment required for 25 pounds of phosphorus is about 75 cents in 200 pounds of fine-ground natural rock phosphate of good grade, about $2.50 in 200 pounds of good steamed bone meal, about $3.00 in 400 pounds of good acid phosphate, about $6.00 in 600 pounds of the average "complete" commercial fertilizer, and about $80 in manure made from corn costing 40 cents a bushel.  The natural phosphate, if ground to pass through a sieve with 10,000 meshes to the square inch, gives satisfactory results when applied in liberal amounts (as 1000 pounds per acre every three or four years), if used in connection with decaying organic matter in sufficient amount to maintain the nitrogen.

     (18)  Potassium salts are used with very great profit on soils positively deficient in that element, as on most well-drained extensive peaty swamp lands; and soluble salts, such as kainit, may produce some profit for a time if used in connection with phosphorus on soils deficient in decaying organic matter, even where the total supply of potassium in the soil is very large.

     (19)  Commercial nitrogen can usually be used with profit in market gardening, in cotton growing, and sometimes in the production of timothy hay near large cities; or, as a rule, wherever the gross returns from an acre of produce exceeds $50 or $75.

     (20)  As a rule, commercial nitrogen cannot be used with profit for the production of the staple grain crops, such as corn and wheat, although under some conditions small applications of nitrogen alone or with other elements, as in the ordinary so-called "complete" fertilizer, may stimulate the plants sufficiently to enable them to draw more heavily upon the soil, and thus return apparent temporary profit in a system of ultimate land ruin.

     And other seed fell on good ground, and sprang up, and bare fruit an hundred fold.--Jesus.
     I applied mine heart to know, and to search, and to seek out wisdom, and the reason of things.--Solomon.
     Every man shall receive his own reward according to his own labor; for we are laborers together with God.--Paul.

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