Fig. 662. Showing small crops of oats. 78, soil from Massachusetts; 72, Illinois; 65, California. (See Fig. 661.) application, which makes the practice entirely safe, provided too large quantities are not used. The ordinary mixtures for corn and other cereal grains are not, as a rule, so concentrated as to cause any serious injury by this method. For example, in the case of corn-planters, the fertilizer is usually dropped first, lightly covered with soil, then the grain is dropped, thus not bringing the seed directly in contact with the fertilizer. In the case of wheat and rye, such separation of the seed from the fertilizer is not possible, though the danger of injury with the usual applications of 200 to 400 pounds per acre is very remote. When larger quantities are used, or when grass or other fine seeds are sown, it is much better to apply the fertilizer previous to seeding, and thoroughly mix it with the surface soil. This may be accomplished by the ordinary broadcasting machines now on the market; or it may be applied with a grain-drill, which deposits the fertilizer immediately under the surface, and the subsequent harrowing will distribute it and prevent any injury to the seed. In the application of fertilizers for market-garden crops, when the amounts are usually very much greater, both methods are used. In the case of white potatoes, 600 to 800 pounds of the fertilizer may be

15 84 $26 34

applied at the time of planting, without injury, provided the mixture does not contain too large a proportion of nitrate or potash salts, though a fertilizer containing as much as 10 per cent of potash may be applied without injuring the germinating power of the seed. This will depend somewhat on the season. If the weather is very dry following the planting, and a dilute solution is not made of the salts, injury may result. Therefore, it is safer to apply a smaller amount with the seed, and the remainder after the crop is planted, either broadcast or drilled in. It is much better, as a rule, to apply the fertilizer on the surface and cultivate it in, than to plow it down, except in the case of fruits and berries.

In ordinary usage, farm manures, in the sense in which we use the term, may be considered under the following sub-divisions: (1) Barnyard manures: This term is commonly used, at least in New England, to designate manure derived principally from cattle. The term was doubtless originally given because such manure usually accumulated in the barnyard. This is no longer usually the case, but the name is still applied to manure of this character whether it be made in stables, cellars or yards. (2) Stable manure: in ordinary American usage, this term designates manure made principally or altogether from horses. (3) Sheep manure. (4) Hog manure. (5) Poultry manure.

General characteristics of farm manures.

If, for the time being, we exclude poultry manures, since these differ in important particulars from the manures derived from the larger domestic animals, we find that there are certain general considerations affecting the value of manures which apply almost equally to each of the four classes.

The manure derived from each of the larger domestic animals in most cases is composed essentially of three different ingredients: dung, urine and litter. The nature of each of these classes of material must be briefly considered.

(1) Dung.-The dung of domestic animals consists of the undigested portions of their food, ground more or less fine according to the nature of the animal, moistened and softened by the addition of different digestive fluids, and, to a slight

extent, admixed with waste tissues of the alimentary canal. The undigested portions of the food found in the dung consist very largely of the woody or fibrous tissues of the food, but the dung that contains these undigested portions is in a much better mechanical condition to act as a manure than the original material, because it has been ground so fine and softened so much that it will decay readily. The dung from domestic animals, although often looked on as the principal part of the manure, possesses considerably less plant-food constituents than the urine. It varies considerably in composition, and some figures comparing it with urine will be found later in this article. In this place, it suffices to point out in a general way that the dung usually contains about one-third of the total nitrogen of the feces, one-fifth of the total potash, and nearly all of the phosphoric acid. The constituents of the fresh dung are not soluble to any great extent and not in condition to serve immediately as the food of plants. Before its elements become to any great extent available, the dung must undergo decomposition.

(2) Urine. The urine of domestic animals, though composed chiefly of water, contains a variety of the compounds produced as the result of metabolic changes acting on the digested portions of food, and to some extent on the worn-out tissues of the body itself. Urine usually contains about two-thirds of the total nitrogen, four-fifths of the potash and but very little of the phosphoric acid voided by the animal. The nitrogen of the urine of the common domestic animals is found chiefly in the form of two rather complex organic compounds, namely, urea (CH,N,O) and hippuric acid (C,H,NO3). Urine very readily undergoes complex fermentations, in the course of which the two nitrogen compounds above named are soon converted into ammonia and ammonium carbonate, and these in turn eventually into nitrates. It is well known that nitrogen in the form of ammonia, ammonia compounds or nitrates, is more readily available as food than are urea and hippuric acid, and yet there is strong evidence which supports the view that these compounds may under some circumstances be directly taken up and assimilated by the plant. Even if this is not under all conditions the case, it is an undoubted fact that the constituents of the urine will become available as food for plants under ordinary conditions far more quickly than the constituents found in the dung.

Relative amounts of dung and urine.-The relative amounts of dung and urine vary widely with the different animals and to some extent with the food. Especially is the last condition of importance in the case of the hog. For the cow, the total weight of urine under normal conditions is about twice the weight of the dung. For the horse and the sheep, there is much less difference. The two are usually of substantially equal weight, although the dung not infrequently weighs somewhat more than the urine. For the hog, the variation in relative amounts is so great that any general statements can have little value. As a rule, however, the urine is relatively very abundant.

Composition of dung, urine and drainage liquors. The serious nature of the loss which the farmer must suffer when he allows any part of the urine of his domestic animals to be lost, or permits the natural drainage from the manure to escape, will be made very apparent by examination of the figures showing the composition of these different classes of materials. The figures presented for dung and urine are taken from Wolff, a German authority, and are the average of a large number of determinations. Perhaps they may not accurately represent similar averages under conditions existing in this country, but the writer has not at hand the data from a sufficient number of American analytical determinations to make the calculation of reliable averages possible.

COMPOSITION OF FRESH EXCREMENT.

One thousand pounds of fresh dung contain :-
Phosphoric
acid

Water

Alkalies

Nitrogen

(3) The litter.-The character and value of manure is very largely affected by the kind and amount of litter used. Litter, while used primarily to afford a comfortable bed and to assist in keeping the animals clean, serves to absorb and retain urine, to absorb gases to some extent, and to dilute the manure, making even distribution easier. The litter may also carry to the manure very considerable amounts of plant-food; and it will improve the manure in its mechanical condition. The constituents of most kinds of litter are in relatively unavailable forms and the material must decompose before its food elements are brought within the reach of the plants.

Various kinds of litter are employed in the different parts of the United States. Among those more commonly available are, straw from the different cereal grains, marsh hay, leaves, corn stover, sawdust and planer shavings, and peat moss. Earth of different kinds, though strictly speaking not litter, is frequently used beneath the animals as a partial or complete substitute therefor and must be here considered.

(a) Straw. The straw of the different grains is one of the most satisfactory materials that can be used for bedding. It has great capacity to absorb urine and has considerable manurial value. The straw of the different grains differs materially in toughness and wearing qualities, but the effect of the different kinds on manure is not materially different. A ton of straw will usually contain about 16 pounds of nitrogen, 4 pounds of phosphoric acid, 26 pounds of potash, and 9 pounds of lime. An average ton of farmyard manure contains about 10 pounds each of nitrogen and potash. A ton of straw, therefore, contains more of these elements than a ton of average manure. It follows then that by the liberal use of straw the proportions of nitrogen and potash in manure by weight will be increased. A cord of strawy manure weighs much less than a cord of clear manure and contains much less plant-food.

(b) Marsh hay. There are two distinct classes of marsh hay in use, namely, salt and fresh. Both kinds have about the same qualities as straw, though somewhat less absorptive. The salt marsh hay does not decay so quickly as straw. There is much variation in the value of hay of these classes for litter, determined chiefly by the species of which it is composed. Fresh marsh hay sometimes contains weed seeds that may prove troublesome. Although the liberal use of either of these kinds of hay as litter will have about the same effect on the composition of the manure as straw, when the latter is employed the manure will generally be preferable.

(c) Leaves.-Leaves nave good absorptive properties, but possess a lower manurial value than either straw or marsh hay. When mixed with manure, they decompose rapidly and the constituents of manure when they have been used for litter will become available within a relatively short time.

(d) Corn stover. Although corn stover has such value for food that its use for litter is inexpedient from an economical point of view, it is neverthe

less not infrequently used for litter. If well dried, it has good absorptive qualities, but unless shredded or cut it is too coarse to be satisfactory. Its manurial value when well dried is about the same as that of straw.

(e) Sawdust and planer shavings. These materials have relatively little manurial value. If thoroughly dried, however, they are good absorbents. There is a wide-spread prejudice against their use on the ground that the soil is rendered sour. So far as can be ascertained, this peculiar effect has never been clearly demonstrated. Neither sawdust nor shavings will add materially to the plant-food content of manure, but when they are used as litter in moderate amounts, the mechanical condition of the manure is good.

(f) Peat moss. This material is as yet relatively little used in the United States, but when such moss can first be thoroughly dried, its use insures the acme of comfort to the animal and excellent sanitary conditions. It is a good absorbent, being capable of taking up about ten times its weight of water, while straw takes up only about three times its weight. The use of peat moss in fairly liberal amounts would be favorable to the production of an excellent quality of manure.

(g) Earth. Sandy earth, especially if coarse, is a relatively poor absorbent. Fine earth, if first well dried, especially if it contains considerable organic matter, is a fairly good absorbent. The use of such earth beneath or behind the animals in stables is calculated to favor the production of manure of good quality. Such earth is superior to strawy litter according to some of the most recent investigations, since it contains much less highly carbonaceous organic matter. It has been found that the presence of excessive amounts of such matter in manure, as, for example, when straw is abundantly used for bedding, produces conditions which are favorable to a considerable loss of nitrogen (the most valuable element of the manure) in the form of uncombined nitrogen gas.

Conditions affecting the value of manures.

It is a well-known fact that the value of farm manures varies widely. This variation is due to two classes of factors: first, those affecting the quality of the excrements as voided; second, exterior factors.

Factors affecting the quality of excrements.—The composition of the excrements from any single class of animals when voided varies widely. The factors exercising the most marked effect are the food of the animal, its age, the products produced by the animal, and its condition.

(a) Food. Other things being equal, the richer the food of the animal in plant-food constituents, most important among which are nitrogen, phosphoric acid, potash and lime, the more valuable are the excreta for manure. The manure from animals fed largely on straw, corn stover or timothy hay, will be comparatively poor, especially in the valuable element nitrogen, because these foods are poor in nitrogen; while the excreta from animals receiving a liberal quantity of such foods as wheat

bran, gluten meal and cottonseed meal will be rich, particularly in nitrogen and phosphoric acid. The excreta from animals fed largely on clover or alfalfa hay will be richer in nitrogen, under otherwise similar conditions, than the excreta from animals fed on timothy hay. Tables issued by many of the Experiment Stations give very full information in regard to the plant-food constituents in .different foodstuffs, but to bring out more fully the fact that variation in food must cause a very wide variation in the composition of animal excreta, a table showing the more important plant-food constituents of some of the foods most generally used is herewith presented :

FERTILIZER INGREDIENTS IN FOODSTUFFS.

muscle. The quality of manure made from well-fed mature animals is likely, therefore, to be considerably better than that made from young animals.

(c) Product. Such essential elements of plantfood as are contained in any products for which animals are fed, such as milk or wool, must, of course, come in the last analysis from the food, and accordingly there remains so much the less of these elements to be voided in the excreta. Milk contains considerable nitrogen and phosphoric acid and a moderate amount of potash. Wool fiber contains a large amount of nitrogen, while in the oil or yolk of eggs a large amount of potash is found. The manure from milch cows is likely to be relatively poor in nitrogen and phosphoric

Pounds in 100.

PhosWater Nitrogen phoric acid

Potash

.34

.33

.49

.38

.71

.39

1.22

1.50

1.56

Mangel-wurzels

acid.

(d) The condition of the animal.—If the animal is low in flesh, or in so-called poor condition, it must take from its food the materials necessary to bring the body into a better or well-nourished condition. This change will make necessary the removal from the food of large quantities of protein (rich in nitrogen) and will to just the extent to which this is taken reduce the value of the manure. The excreta from mature animals which are being fattened are richer than those from any other class of farm animals, for fattening mature animals are increasing the weight of the body by additions consisting almost exclusively of fat, and fat contains neither nitrogen, phosphoric acid nor potash in appreciable amounts. The excreta from fattening growing animals, although reduced in value somewhat by the withdrawal of nitrogen and phosphoric acid for the building of bone and muscle above alluded to, are still likely to be relatively rich in plant-food elements, as the food of such animals is usually rich in such elements.

Exterior factors.-The conditions affecting the saving and preservation of the elements of value in the excreta affect the value of manures in far greater degree than do those factors which affect the quality of the excreta as voided. The most important of the factors which have an influence are stable construction and management, the kind and amount of litter or bedding used, the use or non-use of chemical absorbents and the way in which the manure is stored and kept. The object sought always is prevention of all loss of valuable constituents. The chief sources of loss are, (1) through the escape of urine or natural drainage liquors; (2) by exposure to rain and leaching; (3) by fermentation. If the urine or natural drainage liquors be allowed to escape in whole or in part, or if manure be exposed to the leaching action of heavy rains, there will be a great loss both in nitrogen and in potash, for the greater part of these is originally found in the urine. Fermentation, if not properly controlled and its products saved, results in serious loss of nitrogen.

.75

The conservation of manure.

Whatever the method of preserving manure, the objects are to prevent: first, the ammoniacal fermentation; second, the volatilization of ammonia from urine and manure; third, the activity of the denitrifying organisms.

The statements made concerning the causes and the nature of the changes taking place in manure must have clearly indicated the methods that must be adopted to prevent loss while at the same time securing that improvement in mechanical condition which is a consequence of the softening and gradual decay, especially of the litter. Very briefly, we may sum up the whole matter by saying

Fig. 663. The waste of manure. that manure should, if possible, be kept in a watertight receptacle to prevent loss from drainage; under cover to prevent leaching; compact and moist to prevent too rapid heating; while chemical absorbents may wisely be added to insure against volatilization of ammonia. Manure should be kept compact, moreover, in order to prevent a too large formation of nitrates. The principal part of the nitrogen must enter into combination as nitrates before it is available to the plant, but this change goes on more safely in the soil than in the manure heap. There is danger that if it be allowed to go on too largely in the manure heap, a considerable share of them may be destroyed by the denitrifying organisms that live in the lower parts of the heap. The more nearly manure can be kept under conditions similar to those under which green fodders are kept in a silo, the more certainly will its valuable constituents be conserved.

Stable construction and management.

Stable construction and management are important chiefly because of their bearing on the extent to which the fluid part of the excreta is saved. The figures presented and the statements made must have made it evident that any loss of urine seriously decreases the value of the manure, and yet it is to be feared that to this day there are farmers who act as if they believed such loss to be unimportant. In many of the older stables, much urine was allowed to escape, oftentimes

through cracks in the floor on which the animals stood. In other cases, the manure when removed from the stables was thrown into a heap in the open air, where the rains and in some cases the water from the roofs as well soaked through it, carrying away a considerable proportion of its soluble and most valuable constituents. Such stables, and stables where no provision for the protection of the manure has been made, are still far too frequent. (Fig. 663.)

The details of stable construction may, of course, be almost infinitely varied, but no farmer should lose sight of the fact that loss of urine and leaching of the manure should be prevented. To this end, it is necessary, first, that the platform and the gutter behind the animals shall be water-tight. In some of the best stables, the gutter is sloped to an outlet, from which the urine is led into a cistern or tank set to receive it. This plan is infinitely better than to allow the urine to escape, but for many reasons it seems preferable to keep dung and urine together. Neither by itself is a well-balanced manure. Dung is poor both in nitrogen and potash; the urine contains little phosphoric acid. If the two be kept together, the manure suits the average crop better than either dung or urine alone. Moreover, if the urine be separated from the dung, especially in the case of horses, the latter becomes too dry. Manure keeps better and decomposition goes on under better conditions when it is rather moist. As a rule, then, it seems best to use bedding in sufficient quantity so that the dung and urine may be handled together.

The stable should usually be cleaned twice daily. Many of the older barns and some of those of modern construction have cellars underneath into which the manure is thrown. If the cellar is naturally dry and is made water-tight, it is a good place in which to put manure. There is no other way in which the latter can so conveniently and at so little cost for labor be removed from the stable; but placing manure in a cellar underneath the stable in which animals are kept is objectionable on sanitary grounds. Foul odors and gases inevitably find their way from the cellar into the stable in greater or less degree. True, by thorough ventilation of the cellar and by the free use of chemical absorbents, the disadvantages can be in a measure removed. On the whole, however, it is now generally conceded that manure should not be stored underneath stables in which cows or horses are kept. A better plan is to provide a covered pit convenient of access from the stable. The manure is then collected either by use of receivers carried by overhead trolley tracks (Fig. 664) or in wheelbarrows and conveyed directly to the pit. (Fig. 665.) If this plan is followed, the pits should be of such capacity that the manure can be stored for a few weeks at least. Such pits should be water-tight and roofed and the manure in them, if allowed to remain long, should be occasionally leveled and kept both moist and compact. Provided swine are given access to clean sleeping and feeding quarters, there seems to be no practical objection to allowing them to range over the