The Farm That Won't Wear Out Part 1

The Farm That Won't Wear Out.

by Cyril G. Hopkins.

Preface

THE FARM THAT WON'T WEAR OUT

WAS FIRST published serially in THE COUNTRY GENTLEMAN, the privilege having been granted the author of subsequent publication. It is now issued in book form in response to numerous requests coming especially from the Central, Eastern, and Southern States.

CYRIL G. HOPKINS.

CHAMPAIGN, ILL.

_"Population must increase rapidly, more rapidly than in former times, and ere long the most valuable of all arts will be the art of deriving a comfortable subsistence from the smallest area of soil."--Lincoln._

_"It is not the land itself that const.i.tutes the farmer's wealth, but it is in the const.i.tuents of the soil, which serve for the nutrition of plants, that this wealth truly consists."--Liebig._

CHAPTER I

WHAT GOES TO MAKE UP PERMANENT FERTILITY

IT IS an old saying that "any fool can farm," and this was almost the truth when farming consisted chiefly in reducing the fertility of new, rich land secured at practically no cost from a generous Government. But to restore depleted soils to high productive power in economic systems is no fool's job, for it requires mental as well as muscular energy; and no apologies should be expected from those who necessarily make use of technical terms in the discussion of this technical subject, notwithstanding the common foolish advice that farmers should be given a sort of "parrot" instruction in almost baby language instead of established facts and principles in definite and permanent scientific terms. The farmer should be as familiar with the names of the ten essential elements of plant food as he is with the names of his ten nearest neighbors. Safe and permanent systems of soil improvement and preservation may come with intelligence--never with ignorance--on the part of the landowners.

When the knowledge becomes general that food for plants is just as necessary as food for animals, then American agriculture will mean more than merely working the land for all that's in it. This knowledge is as well established as the fact that the earth is round, although the people are relatively few who understand or make intelligent application of the existing information.

Agricultural plants consist of ten elements, known as the essential elements of plant food; and not a kernel of corn or a grain of wheat, not a leaf of clover or a spear of gra.s.s can be produced if the plant fails to secure any one of these ten elements. Some of these are supplied to plants in abundance by natural processes; others are not so provided and must be supplied by the farmer, or his land becomes impoverished and unproductive.

Foods That Plants Live On

Two elements, carbon and oxygen, are contained in normal air in the form of a gas called carbon dioxid, and this compound is taken into the plant through the breathing pores, which are microscopic openings located chiefly on the under side of the leaves. Some plants have more than a hundred thousand breathing pores to the square inch of leaf surface.

When plants or plant products are burned or decomposed the carbon of the combustible material--gra.s.s, wood, coal, and so forth--unites with the free oxygen of the atmosphere to re-form the carbon dioxid, which thus returns as a gas to the air. Even the food taken into the animal system, after being digested and carried into the blood, is brought, into contact with the oxygen of the air--which also pa.s.ses into the blood through the cell walls of the lungs--and a form of combustion takes place, the heat generated serving to warm the body while the carbon dioxid pa.s.ses back into the lungs and is exhaled into the open air.

By these circulation processes the supply of carbon dioxid in the atmosphere is renewed and maintained without any special effort on the part of man. Hydrogen is one of the elements of which water is composed. Water is taken into the plant through the roots, carried through the stems to the leaves, and there, under the influence of chlorophyll, sunlight and the life principle, the carbon, oxygen and hydrogen are made to unite into some of the most important plant compounds, such as the sugars, which are later transformed into starch and fiber.

Though these three elements const.i.tute the larger part of the mature agricultural plant they are no more necessary for plant growth than the seven which are supplied by the soil. Iron is one of the essential elements of plant food; but the amount required by plants is so small and the amount contained in the soil is so large that soils have never been known to become deficient in iron. Though sulfur is found in plants in very appreciable amounts and is known to be essential to plant growth, it is evident that plants do not need so much sulfur as they often contain, some of it being taken up and merely tolerated, as is the case with all of the sodium and silicon found in plants, neither of these being required for normal growth, although commonly found in plants in very considerable amounts. The supply of sulfur in normal soils is not large; but, with the combustion and decay of organic materials--coal, wood, gra.s.s, leaves, and so forth--sulfur pa.s.ses into the air and is brought back to the soil dissolved in rain or absorbed by direct contact of soil and air. Thus under normal conditions the supply of sulfur naturally provided is ample to meet the needs of the staple farm crops, although there are some plants, such as cabbage, for example, which may possibly be benefited by fertilizing with sulfur.

But there are five other essential elements of plant food, and these require special consideration in connection with permanent soil fertility. They are pota.s.sium, magnesium, calcium, phosphorus and nitrogen. There are also five important points to be kept in mind in relation to each of these elements: (1) the soil's supply, (2) the crop requirements, (3) the loss by leaching, (4) the methods of liberation, and (5) the means of renewal.

The neglect of one or more of these important points in relation to one or more of these five elements has reduced the fertility of most cultivated soils in the United States, has greatly impoverished the older farm lands, and has brought agricultural abandonment to millions of acres in the original thirteen states. On the other hand, intelligent attention to these same factors will bring restoration and high productive power to such lands.

England's Best Lesson in Farming

Where these five elements were supplied regularly to land on the Rothamsted Experiment Station the average yield of wheat for the thirty years, 1852 to 1881, was 35.9 bushels an acre, while 13.6 was the average yield of similar unfertilized land; and during the next thirty years--1882 to 1911--the corresponding average yields were 38 bushels an acre on the fertilized land, and 11.7 bushels where no plant food was applied. These statements are not mere opinions, but determined facts whose accuracy stands unquestioned.

On another field at Rothamsted, England, the average yield of barley for the same sixty years was 43 bushels an acre where nitrogen, phosphorus and calcium were regularly applied, 42.6 where all five elements--including pota.s.sium and magnesium--were added, but only 14.3 on unfertilized land.

On still another Rothamsted experiment field, where a four-year crop rotation of turnips, barley, clover (or beans) and wheat has been practiced since 1848, the yield of turnips in 1908 was 717 pounds an acre on unfertilized land and 35,168 pounds where the five important elements of plant food had been regularly applied once every four years--for the turnips only--since 1848. In 1909 the barley yielded 33.4 bushels an acre on the fertilized land, but only 10 bushels where no plant food was applied. The yield of clover in 1910 was 8590 pounds an acre on the land fertilized for turnips, but only 1949 on the unfertilized land. The wheat following the clover with no other fertilizer produced 24.5 bushels an acre in 1911, but 38 bushels where plant food is always applied for turnips grown three years before.

These are the established facts from the longest accurate record, and thus the most trustworthy data the world affords; and when one hears promulgated the very pleasing doctrine that the rotation of crops will maintain the fertility of the soil it is time to remember that "to err is human."

Fertility in Normal Soils

Of the four important mineral elements, pota.s.sium is by far the most abundant in common soils. Thus, as an average of ten residual soils from ten different geological formations in the eastern part of United States, two million pounds of subsurface soil were found to contain:

Pota.s.sium 37,860 pounds Magnesium 14,080 pounds Calcium 7,810 pounds Phosphorus 1,100 pounds

Even the depleted, and to some extent abandoned, gently undulating upland "Leonardtown loam," which was farmed for generations and which, according to the surveys of the Federal Bureau of Soils, covers 41 per cent of St. Mary's County, Maryland, and more than 45,000 acres of Prince George's County--still contains in two million pounds of surface soil--corresponding to the plowed soil of an acre about 6-2/3 inches deep:

Pota.s.sium 18,500 pounds Magnesium 3,480 pounds Calcium 1,000 pounds Phosphorus 160 pounds

The brown silt loam prairie soil of the early Wisconsin glaciation is the most common type of the greatest soil area in the Illinois Corn Belt. Two million pounds of this surface soil contain as an average:

Pota.s.sium 36,250 pounds Magnesium 8,790 pounds Calcium 11,450 pounds Phosphorus 1,190 pounds

The older gray silt loam prairie, the most extensive soil of Southern Illinois, contains in two million pounds of soil:

Pota.s.sium 24,940 pounds Magnesium 4,690 pounds Calcium 3,420 pounds Phosphorus 840 pounds

These data represent averages involving hundreds of soil a.n.a.lyses, and they emphasize the fact that normal soils are rich in pota.s.sium and poor in phosphorus. This is to be expected, for most soils are made from the earth's crust, and normal soils should bear some relation in composition to the average of the earth's crust, which contains in two million pounds 49,200 pounds of pota.s.sium and 2,200 pounds of phosphorus, as shown by the weighted averages of a.n.a.lyses involving about two thousand samples of representative rocks, reported by the United States Geological Survey.

Measuring Fertility Losses

The plant food required for one acre of wheat yielding 50 bushels, one acre each of corn and oats yielding 100 bushels, and one acre of clover yielding four tons, includes for the total crops:

Pota.s.sium 320 pounds Magnesium 68 pounds Calcium 168 pounds Phosphorus 77 pounds

If only the grain, including a yield of 4 bushels an acre of clover seed, is considered, the straw, stalks and hay being returned to the soil--either directly or in farm fertilizer--then the loss per acre from four years of cropping as above would be as follows:

Pota.s.sium 51 pounds Magnesium 16 pounds Calcium 5 pounds Phosphorus 42 pounds

The average annual loss by leaching from good soils in humid sections is known by the results of many a.n.a.lyses to be about as follows per acre:

Pota.s.sium 10 pounds Calcium 300 pounds Phosphorus 2 pounds