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PAPERS READ AT

FARMERS' INSTITUTES, 1904-1905.

Forwarded to the Secretary of Agriculture for Publication in the Annual Institute

Report.

SOIL STUDY

BY A. ALVIN STAHL, GREENFORD, OHIO.

[Read at the Farmers' Institute held at Canfield, Mahoning county, February

15 and 16, 1905.]

It is a truism that the prerequisite to success in any business or professional undertaking is a good, solid, well-constructed found' tion. In one instance it may be of an intellectual character, a thorough ko wledge of the details of that business or profession, or it may be of a material nature, as a solid, wellconstructed roadbed is a prerequisite to a successful railway line. It is to this latter class that belongs the prerequisite to successful agriculture, a fertile soil. Of course, there are other essentials, but other things being equal that farmer will meet with the greatest degree of success who is blessed with a fertile, hence a productive soil.

It shall be my aim in this brief paper to give as far as possible the facts in regard to the origin and composition of soils, the agencies which have been most active in soil formation, and a few hints as to plant food and the maintenance of soil fertility.

It is not an absolute necessity that the farmer know all the elements that enter into the chemical composition of soils or that he know in just what proportion the elements exist which determine the mechanical condition of a soil, nevertheless the origin and composition of soils present an interesting field of study. A great many of our farmers are not as familiar as they should be with the origin of soils. It is still believed by some that the soil which we till served as a covering of the earth when it was formed, but this idea is erroneous, as it has become what it is by a slow process. Soil was formed and is constantly being formed by disintegration and rotting down of rock under the slow action of the atmosphere. The active ingredients of the air in this process are oxygen, carbonic and acid and water as vapor or moisture. Rain water which contains these ingredients, is therefore, the most active agent in soil formation. It water, the chief agent of decomposition,' were limited in its action to the surface of the rock the process would indeed be much slower than it is, but, fortunately all rocks are affected with joints in several directions; water, therefore penetrates to great depths, attacking the surface of each block, which in turn is affected by fissures through which the water penetrates, thus greatly increasing the surface exposed to disintegrating agencies. The above, which is a chemical action of the elements upon the rock, can easily be illustrated by taking a piece of mortar, placing it in hydrochloric acid which dissolves the lime that hold the grains of sand together and the whole mass crumbles. In all rocks some parts are soluble in water and some are not, thus by the continued action of this agent the soluble parts are dissolved while the insoluble portions break down into powder. The difference between the two processes is that the former is rapid while the latter is very slow. In cold climates water also exerts a mechanical action by entering the joints and fissures, where, freezing, it expands and bursts asunder the rock, thus greatly increasing the rapidity of soil formation.

Proofs of this mode of formation are shown most clearly in those cases where the soil still remains resting on the rock from which it was formed. These cases are, however, very rare in the northern part of our country, as the soil has been shifted during a period known as the "drift period." They are clearly shown in the southern part of the United States or in the southern counties of our own state where the soil has remained undisturbed for ages.

By observing the sections made by a railway cut we find at the surface a perfect soil, just below, perhaps, it becomes lighter colored and coarser grained, then begins to look like rotted rock, and gradually passes into sound rock. The evidence is still more complete if the rock chances to be traversed by a vein of more enduring rock, which has withstood the action of the atmospheric agencies, when it can be traced to near the surface.

But we need not go out of our own community to see the process of soil formation going on. Rocks which originally had sharp edges have been worn smooth and at places i ere the rock outcrops at the base of the cliffs may be found piles of rock an. fragments in different stages of decay. The depth and kind of soil depends upon the kind of rock from which it was formed. The depth is also influenced by the rapidity with which it is removed by soil washing. Soil removal is effected by surface water and by streams. Surface water carries it from the highlands to the lowlands and deposits it or carries it into the stream, which in turn carries it to the ocean or during an overflow deposits it over the valley through which it flows.

During a period known as the “glacial epoch," the whole northern section of the United States was covered by a huge glacier which extended as far south as 40 to 38 degrees north latitude, carrying with it vast areas of soil and depositing it along its path. The terminal moraine of this glacier may be traced through Ohio, passing through Columbiana, Stark, Wayne, Richland, Holmes, Licking, Fairfield, Rosi, Highland, Adams and Brown counties and crossing the Ohio River into Kentucky from the latter county. This gives to the state a variety of soils adapted to a wide range of crops. The average depth of this drift in Ohio is about one hundred feet, but in some sections it attains a depth of over five hundred feet.

The chemical elements of a soil which are essential to plant growth and which are of most interest to the farmer are ten in number, namely: Nitrogen, potassium, phosphorus, magnesium, sulphur, sodium, iron, chlorine, silicon and calcium.

The mechanical components of the soils of Ohio are found chiefly in sand, silt and clay. Those soils containing high percentages of sand will be loose and open; those with less sand are called loamy; those containing high percentages of silt will pack quickly under rainfall and may become hard, while those containing much clay will be plastic, retentive of moisture and likely to become cloddy in working. From the above it will be seen that the physical character of a soil is an important factor in determining actual fertility. This has reference, first, to the original character of the rock from which the soil particles were derived, whether hard and dense in their mineral character, thus resisting the penetration and solvent effect of air and water and other agencies, or soft and friable, and freely permitting their. entrance and action; and, secondly, whether in the formation of the soil the particles were so fine and so free from vegetable matter as to settle in hard and compact masses impervious to water, air and warmth, or whether they were coarse and not capable of close compaction, thus giving rise to an open friable soil, freely admitting the active natural agencies which are so necessary to plant growth, for the free circulation of the air and water through the soil is necessary that they may dissolve and make available the plant food and carry it to the plant.

The temperature of the soil and of the surrounding atmosphere must not be too high or too low, thus preventing the progress of those changes which must go on, both in the soil and in the plant that the normal growth and development may be accomplished. Then the great importance of adding vegetable matter or humus to a soil is to give body to a light, sandy soil, leaving it less porous, enabling it to retain a greater amount of moisture, thus keeping a larger proportion of the plant food within reach of the plant roots; to make a cold, compact clay, or other soil of similar nature loose and friable, allowing a free circulation of air and water, increasing its moisture containing capacity, allowing less rainfall to run from the surface; by its decomposition to raise the temperature of these cold soils.

When the earth was formed it is thought that the chemical elements were more uniformily distributed throughout its crust than they are at present, owing to changes that have taken place by the removal of soils from their place of formation and their deposition at other places.

The mechanical components have become separated and deposited, the coarser first, forming sand, then the finer forming clay, and perhaps lime in another forming limestone soil; all differing from each other in the amounts and proportions of the essential fertilizing constituents contained, as well as in their physical qualities. The sandy, gravelly soils being the poorest are usually deficient in phosphoric acid and potash and not rich in nitrogen; clay soils are frequently rich in minerals containing potash and poor in those containing lime and phosphoric acid. Limestone soils are usually deficient in potash and rich in lime and phosphoric acid. Those soils composed largely of vegetable matter are rich in nitrogen and deficient in all the mineral elements. Hence it is that in the use of commercial fertilizers a knowledge of the soil is important and that we may supply those that are needed in that type of soil. Perhaps the best method of learning the element or elements that give us the largest increase in crop production is by experiment with the different elements of plant food upon the growing crop.

of the ten chemical elements necessary to plant growth all are found in most soils in sufficient quantities with the exception of three or at the most, four, namely: Nitrogen, phosphoric acid, potash and lime. These are liable to become exhausted because they exist in larger quantities than the others in the plants grown and in smaller amounts in the most fertile soil. Nitrogen in its simple form is a gas and as such cannot be used in fertilizers. Therefore, when we speak of nitrogen in fertilizers we do not mean that it exists as simple nitrogen, but in combination with other elements, perhaps in different forms, as nitrate of soda-which is nitrogen combined with soda; as ammonia, which is nitrogen combined with hydrogen, or it may be in the form of organic matter.

The function of nitrogen is to grow the stems and leaves of plants, and an abundance is indicated by a luxuriant growth of these parts and a deepened color of the foliage. Potash is essential to the formation of starch in plants. Starch is first formed in the leaves of plants after which it becomes soluble enough within the plant cells to pass through the cell walls and is carried to the fruit of the plant where it accumulates and changes back to its insoluble form. Potash exerts an important influence on the development of the woody parts of stems and the fleshy parts of fruit.

Experiments have proven that plants will die before reaching maturity unless they have phosphoric acid to feed upon. Phosphates perform three functions. They aid in the nutrition of plants by supplying the needed quantities of phosphoric acid. They aid the plant to assimilate or make use of the other ingredients and are found chiefly in the seeds of plants. A plant does not mature and so does not produce seed unless phosphates are present in the soil in an available form. Certain forms of phosphates render the albumoinoids sufficiently soluble to enable them to be carried from the growing parts of the plant to the seed where they accumulate.

The function of lime is to improve the mechanical condition of soil, by loosening heavy clay soils and by holding together and giving body to light sandy soils. Lime aids in the decomposition of animal and vegetable matter and tends to convert them into available plant food. Therefore, care should be taken to use it with or in connection with fertilizers. Lime serves an important purpose in correcting the acidity of soils. I would like to add that several years ago I had the pleasure of testing samples of the different soil types found in Green township with litmus paper and found all the samples which I tested to be quite acid; therefore, I believe that the farmers of this section would be benefited by the use of lime.

Plant food as used on most farms is obtained from three sources, namely: legumes or nitrogen gatherers, farmyard manures and commercial fertilizers. The nitrogen gatherers belong to the legume or clover family and the distinguishing features of plants of this order are that their seeds are formed in pods or legumes and they have the power of acquiring at least part of their nitrogen from the air. In order that the plant may obtain its nitrogen from the air the soil must originally contain or must be inoculated with a germ, the presence of which is manifested by the growth of nodules on the roots, through which it is believed the nitrogen is obtained. The nitrogen thus introduced into the soil is in a very good form, that is, it readily decays, and thus supplies the needs of other plants.

But it must be remembered that the helpful additions to the soil are limited to organic matter and nitrogen, and the usefulness of the crop will depend upon the available mineral elements in the soil or on those supplied.

Farm manures add directly to the fertility of a soil by supplying all three elements of plant food in the organic form which must be broken down by decay, thus gradually liberating the plant food which they contain. Besides supplying the elements of plant food, farm manures serve another purpose, as do the legumes, that of supplying organic matter, which by its decay renders available some of the plant food already in the soil. and, as before mentioned. they greatly affect the physical condition of the soil.

Commercial fertilizers, on the other hand, in most cases supply only the elements of plant food and may not leave a beneficial effect upon the soil. Rock phosphate, for instance, as a carrier of phosphoric acid does not leave the soil in as good a condition to grow such crops as clover as does steamed bone. The rock goods are manufactured from phosphatic rock, which does not contain organic matter and which when finely ground is treated with sulphuric acid to render the phosphoric acid available, while steamed bone is an animal product and does not undergo the acid treatment which may account for its better effect.

By practicing the following rules, the fertility of the soil can be maintained and increased:

By keeping the ground covered with some growing crop there is little loss of plant food. By proper crop rotation the exhaustion of plant food is lessened. By the use of legumes, nitrogen, the most costly element of plant food, may be obtained from the air. By better tillage and more tile draining the soil may be kept in good condition. By the intelligent purchase and use of commercial fertilizers fertility may be maintained. Most important of all, by marketing the products of the farm as far as possible through the medium of live stock and by care in saving and handling the manure, the greater part of the fertilizing elements may be returned to the soil.

The loss occasioned by the improper care of manure is enormous. It is estimated that if one-tenth of the present waste were avoided the amount of plant food saved would be more than equivalent to the amount purchased in the form of commercial fertilizers. Those interested in the study of fertilizers will find Professor Voorhees' book on that subject helpful. Bulletin No. 750 of the Ohio Experiment Station on “Ohio Soil Studies” will also be helpful to those interested along that line.

GROWING CLOVER.

BY WILLIAM C. COOMBS, LINDALE, OHIO.

[Read at the Farmers' Institute held at Laurel, Clermont county, January

4 and 5, 1905.]

You have doubtless all been advised to grow clover as a means of enriching your land. I have heard it from my boyhood up. All the agricultural books and papers are full of it. Judging from all that is said and written about it, growing clover must be a good thing—too good a thing for you or me to fail to get.

Yet how many of you have really succeeded in growing enough clover to have derived ary marked benefit from it? If I were to visit all the upland farms within a few miles of this place, and look into all your barns, how many good mowfuls of clover hay would I find? Occasionally, by a combination of favorable circumstances or by special and expensive preparation, you have had a field of good clover, but perhaps it would be years before you got another one. You have bought high priced seed nearly every year, and found it hard to pay for, and yet failed in most cases to realize any adequate return for your investment. Why is this? Is it possible that our upland farms will not grow clover, and is it true that we must forego the advantages that are said to result from it? If such advantages as are claimed follow the growing of clover, and it can be grown on our upland farms, we ought to raise it, we can not afford not to do it. If this paper shall help my fellow farmers to grow clover successfully and they actually do it on their farms, then my object shall have been accomplished, and I shall be satisfied. You will also doubtless excuse me for simply giving my personal experience. A relation of what has

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