George E. Waring

“ The changes which nitrogen undergoes, from plants to animals, or, by decomposition, to the form of ammonia in the atmosphere, are as varied as those of carbon and the constituents of water. The same little atom of nitrogen may one year form a part of a plant, and the next become a constituent of an animal, or, with the decomposed dead animal, may form a part of the soil. If the animal should fall into the sea he may become food for fishes, and our atom of nitrogen may form a part of a fish. ”

“ If a bushel of charcoal be mixed with the soil now, it will be the same bushel of charcoal, neither more nor less, a thousand years hence, unless some influence is brought to bear on it aside from the growth of plants. It is true that, in the case of the decomposition of organic matter in the soil, certain compounds are formed, known under the general names of humus and humic acid, which may, in a slight degree, affect the growth of plants, but their practical importance is of too doubtful a character to justify us in considering them. ”

“ When water is made to cover the earth, especially if its rapid motion be arrested, much of this fertilizing matter settles, and is deposited on the soil. The water which sinks into the soil carries its impurities to be retained for the uses of plants. When, by the aid of under-drains, or in open soils, the water passes through the soil, its impurities are arrested, and become available in vegetable growth. It is, of course, impossible to say exactly what kind of mineral matter is supplied by water, as that depends on the kind of rock or soil from which the impurities are derived ”

“ The only way in which lime can exhaust the inorganic part of the soil is, by altering its condition, so that plants can use it more readily. That is, it exposes it for solution in water. We have seen that fertilizing matter cannot be leached out of a good soil, in any material quantity, but can only be carried down to a depth of about thirty-four inches. Hence, we see that there can be no loss in this direction; and, as inorganic matter cannot evaporate from the soil, the only way in which it can escape is through the structure of plants. ”

“ Thus we see that, in the provisions of nature, carbon, the grand basis, on which all organized matter is founded, is never permanent in any of its forms. Oxygen is the carrier which enables it to change its condition. For instance, let us suppose that we have a certain quantity of charcoal; this is nearly pure carbon. We ignite it, and it unites with the oxygen of the air, becomes carbonic acid, and floats away into the atmosphere. ”

“ It is evident that this is the case from the fact that plants have it for their direct object to make over and put together the refuse organic matter, and the gases and the minerals found in nature, for the use of animals. If there were no natural means of rendering the excrement of animals available to plants, the earth must soon be shorn of its fertility, as the elements of growth when once consumed would be essentially destroyed, and no soil could survive the exhaustion. There is no reason why the manure of man should be rejected by vegetation more than that of any other animal ”

“ It is not necessary for farmers to become chemists. All that is required is, that they should [Pg 13] know enough of chemistry to understand the nature of the materials of which their crops are composed, and how those materials are to be used to the best advantage.
This amount of knowledge may be easily acquired, and should be possessed by every person, old or young, whether actually engaged in the cultivation of the soil or not. All are dependent on vegetable productions, not only for food, but for every comfort and convenience of life. ”

“ In the early prosecution of the study, you will find, perhaps, nothing to relieve its tediousness; but, when the foundation of agricultural knowledge is laid in your mind so thoroughly that you know the character and use of every stone, then may your thoughts build on it fabrics of such varied construction, and so varied in their uses, that there will be opened to you a new world, even more wonderful and more beautiful than the outward world, which exhibits itself to the senses. Thus may you live two lives, each assisting in the enjoyment of the other. ”

“ It is true that the phosphate is the most lasting manure; but, once for all, let us caution farmers against considering this a virtue in mineral manures, or in organic manures either, when used on soils con [Pg 184] taining the proper absorbents of ammonia. They are lasting, only in proportion as they are lazy. Manures are worthless unless they are in condition to be immediately used. The farmer who wishes his manures to last in the soil, and to lose their use, may be justly compared with the miser, who buries his gold and silver in the ground for the satisfaction of knowing that he owns it. ”

“ How do under-drains increase the benefits of irrigation?
Irrigation does not come strictly under the head of inorganic manures, as it often supplies ammonia to the soil. Its chief value, however, in most cases, must depend on the amount of mineral matter which it furnishes.
The word "irrigation" means simply watering. In many districts water is in various ways made to overflow the land, and is removed when necessary for the purposes of cultivation. All river and spring water contains some impurities, many of which are beneficial to vegetation. ”

“ Chemical analysis will tell us the composition of a soil, and an examination, such as any farmer may make, will inform us of its deficiencies in mechanical character, and we may at once resort to the proper means to secure fertility. In some instances the soil may contain every thing that is required, but not in the necessary condition. For instance, in some parts of Massachusetts, there are nearly barren soils which show by analysis precisely the same chemical composition as the soil of the Miami valley of Ohio, one of the most fertile in the world. ”

“ We have, nevertheless, a means of restoring to fertility many of our worn-out lands, and preserving our fertile fields from so rapid impoverishment as they are now suffering. Many suppose that soils which produce good crops, year after year, are inexhaustible, but time will prove to the contrary. They may possess a sufficiently large stock of phosphoric acid, and other constituents of plants, to last a long time, but when that stock becomes so reduced, that there is not enough left for the uses of full crops, the productive power of the soil will yearly decrease, until it becomes worthless. ”

“ If we burn any vegetable substance it disappears, except a small quantity of earthy matter, which we call ashes. In this way we make an important division in the constituents of plants. One portion dissipates into the atmosphere, and the other remains as ashes.
That part which burns away during combustion is called organic matter; the ashes are called inorganic matter. The organic matter has become air, and hence we conclude that it was originally obtained from air. The inorganic matter has become earth, and was obtained from the soil. ”

“ If such were not the case, the fertility of the earth must soon be destroyed, as all of those elements which the soil must supply to growing plants would be carried down out of the reach of roots, and leave the world a barren waste, its surface having lost its elements of fertility, while the downward filtration of these would render the water of wells unfit for our use. ”

“ Salt, even in quantities large enough to denude the soil of all vegetation, is never permanently injurious. After the first year, it becomes resolved into its constituents, and furnishes chlorine and soda to plants, without injuring them. One bushel of salt in each cord of compost will not only hasten the decomposition of the manures, but will kill all seeds and grubs—a very desirable effect. While small quantities of salt in a compost heap are beneficial, too much (as when applied to the soil) is positively injurious, as it arrests decomposition ”

“ May mechanical effects be produced by chemical action?
How does potash affect the soil?
To understand the science of manures is the most important branch of practical farming. No baker would be called a good practical baker who kept his flour exposed to the sun and rain. No shoemaker would be called a good practical shoemaker, who used morocco for the soles of his shoes, and heavy leather for the uppers. No carpenter would be called a good practical carpenter, who tried to build a house without nails, or other fastenings. So with the farmer. ”

“ A single experiment will suffice to show that night soil may be so kept that there shall be no loss of its valuable gases, and consequently no offensive odor arising from it, while it may be removed and applied to crops without unpleasantness. All that is necessary to effect this wonderful change in night soil, and to turn it from its disagreeable character to one entirely inoffensive, is to mix with it a little charcoal dust, prepared muck, or any other good absorbent—thus making what is called poudrette. ”

“ Every ton of guano imported into the United States is an addition to our national wealth, but every ton of stable-manure, or poultry-dung, or night soil evaporated or carried away in rivers, is equally a deduction from our riches. If the imported manure is to really benefit us, we must not allow it to occasion the neglect and consequent loss of our domestic fertilizers. ”

“ After we know the exact composition of the soil—which we can learn only from correct analysis—we may manure it with a view either to making it fertile for all kinds of plants or only for one particular plant. For instance, we may find that a soil contains a very little phosphoric acid, and no potash. ”

“ The same mulching might be more cheaply done with leaves, or other refuse matter, and the ammonia of the manure made available by composting with absorbents.
Why is snow particularly beneficial?
It is an old and true saying that "snow is the poor man's manure." The reason why it is so beneficial is, chiefly, that it acts as a most excellent mulch. It contains no more ammonia than rain-water does; and, were it not for the fact that it protects the soil against loss of heat, and produces other benefits of mulching, it would have no more advantageous effect. ”

“ This we have called inorganic matter, and it is obtained from the soil. Organic matter, although forming so large a part of the plant, we have seen to consist of four different substances. The inorganic portion, on the contrary, although forming so small a part, consists of no less than nine or ten different kinds of matter. [B] These we will consider in order. In their relations to agriculture they may be divided into three classes—alkalies, acids, and neutrals. [C]
Is the character of a compound the same as that of its constituents? ”

“ The atmosphere contains results, which have been produced by the breathing of animals and by the decomposition of various kinds of organic matter, which are exposed to atmospheric influences. These gases are chiefly ammonia and carbonic acid, both of which are largely absorbed by water, and consequently are contained in rain, snow, etc., which, as they enter the soil, give up these gases to the charcoal, and they there remain until required by plants. Even the air itself, in circulating through the soil, gives up fertilizing gases to the carbon, which it may contain. ”

“ If the soil do not contain a sufficient quantity of absorbent matter, such as clay or charcoal, the gases arising from the organic matter are liable to escape; but when there is a sufficient amount of these substances present (as there always should be) , these gases are [Pg 164] all retained until required by the roots of plants. Hence, although the organic matter of manure and vegetable substances may be altered in form, by the use of lime, it can escape (except in very poor soils) only as it is taken up by roots to feed the crop, and such exhaustion is certainly profitable ”

“ As food for plants, lime is of considerable importance. All plants contain lime—some of them in large quantities. It is an important constituent of [Pg 161] straw, meadow hay, leaves of fruit trees, peas, beans, and turnips. It constitutes more than one third of the ash of red clover. Many soils contain lime enough for the use of plants, in others it is deficient, and must be supplied artificially before they can produce good crops of those plants of which lime is an important ingredient. The only way in which the exact quantity of lime in the soil can be ascertained is by chemical analysis. ”

“ This power of water has a direct application to agriculture, because the water constituting rains, dews, &c., absorbs the ammonia which the decomposition of nitrogenous matter had sent into the atmosphere, and we find that all rain, snow and dew, contain ammonia. This fact may be chemically proved in various ways, and is perceptible in the common operations of nature. Every person must have noticed that when a summer's shower falls on the plants in a flower garden, they commence their growth with fresh vigor while the blossoms become larger and more richly colored. ”

“ When plants are destroyed by decay, or burning, their organic constituents pass away as water, ammonia, carbonic acid, etc., ready again to be taken up by other plants.
The inorganic matters in the soil can enter the plant only when dissolved in water. Potash, soda, lime, and magnesia, are soluble in their pure forms. Magnesia is injurious when present in too large quantities.
Sulphuric acid is often necessary as a manure, and is usually most available in the form of sulphate of lime or plaster. It is also valuable in its pure form to prevent the escape of ammonia from composts. ”