Everybody understands that the soil becomes impoverished by continued cropping, if no return be made in the form of manure or fertilizer. This impoverishment is sometimes real, while sometimes it is more apparent than real, owing to the exhaustion of only one or two elements of fertility.

Farmers have learned a great deal about agricultural chemistry since the introduction of artificial fertilizers. They know that while plants demand many things for their growth, there are but three elements which are in danger of being exhausted in ordinary cropping. These three things are nitrogen, phosphoric acid and potash.

Lime.—Lime is used on the land not for its direct results as a fertilizer, but because it has the ability to break up combinations already existing in the soil and set free the plant food that previously was in an insoluble form. Lime sometimes produces almost marvelous results; at other times no visible effects whatever. Hence, it is not a fertilizer, though in actual practice it is sometimes a fertilizing agent of great value. Land that has been much manured or long in sod is likely to be benefited by lime.

Artificial manures, on the other hand, furnish real plant food in soluble form, and may be expected to produce crops invariably, year after year, if the soil be sufficiently moist. When a fertilizer contains nitrogen, phosphoric acid and potash it is said to be complete. When any element is missing the fertilizer is said to be incomplete. Ground bone, wood ashes, South Carolina rock, kainit, etc., are examples of incomplete fertilizers.

Barnyard Manure.—Barnyard manure is the best of all known fertilizers. Not only is it complete in character, but it has the highly valuable property of bulk. It is rich in humus or humus-forming materials. It opens and ventilates the soil, and improves its mechanical condition to a remarkable degree. Humus is a name for decaying organic matter.

American market gardeners deem it entirely safe to use fifty to seventy-five tons of barnyard manure to the acre of ground in their intensive cultural operations. American farmers seldom apply more than ten or fifteen tons of such manure to the acre in the open field.

The manufacture of artificial fertilizers had its origin in the fact that cultivators could not get enough manure from natural sources, and, hence, were compelled to go into the market and buy nitrogen, phosphoric acid and potash in other forms.

Closer Economy.—With the increase of competition and consequent fall of prices a closer economy in cost of production is necessary. Prices have fallen most in respect to commodities that will bear long-distance freight transit and less in respect to the more perishable products of the soil. Hence, farmers have widely turned attention to small fruits and vegetables for money crops, instead of grains, and are now studying how to fertilize these crops in the most effective and economical manner.

It is very evident that while great quantities of fertility are demanded by the new crops, there is no such margin of profit in their culture as to warrant wasteful methods, and no losses of home-produced fertility can be tolerated.

As to Saving Manure.—A penny saved is a penny earned. A half ton of manure saved is a dollar earned; and, conversely, a half ton of manure wasted is a dollar wasted. In many American barnyards much of the manure is lost, partly by leaching and partly by escape of ammonia. It is estimated that as much as a third of the natural manure produced in this country is practically thrown away.

The Cornell Station has announced that a pile of horse manure exposed to the weather will lose half of its value in six months. The Kansas Station reaches nearly the same conclusion about farmyard manure.

Manure stored under cover may lose from 14 to 30 per cent. of its nitrogen (ammonia); and as this element is the most expensive of all to buy, it is evident that the loss is a very serious one, and one that should be avoided if possible.

General Principles of Storage.—Having pointed out the fact that on many farms there is a loss of a large amount of excellent manure, it is now in order to name a remedy. The compass of this book is so limited that it is necessary to go straight to the point, omitting a detailed account of the chemical processes involved.

The best-known method of keeping all the manure produced by farm animals is storage under a closed shed, supplemented with chemical preservatives. The shed need not cover the barnyard, but merely the manure pile. The preservatives cost little money, and eventually go to the soil in the form of excellent fertilizers. Not a cent paid for them need be lost.

The manure shed should be large enough to work in with comfort; large enough to permit the heap or heaps of manure to be turned, worked over and shifted from place to place. A clay or earth floor will answer every purpose, and the shed may be of the cheapest character, provided it will turn the rain. The floor of the manure shed should slope inward from all directions, and the drainage around the shed should be outward, so that no rain-water or snow-water can enter.

In theory, it may be best to put fresh manure on the land as quickly as possible. All leaching is then received by the soil, and little is lost, except through the air.

In practice, this plan is not always a good one. It costs more to make ten trips to the field than one trip, and valuable time is wasted. It is quite out of the question to haul out manure every day or even every week. Besides, it is necessary in actual practice, especially in gardening or truck farming, to cover a whole piece of ground at one time, so that it may be plowed and seeded for the coming crop. The ground is usually available only a short time before this preparation, having, perhaps, been occupied by something else. It is desirable, moreover, that the manure when applied shall be ready for immediate service as plant food, which is not the case with the raw product. Fresh manure is but sparingly digestible by plant roots. Quicker cash results will be secured by applying prepared manure to the soil than by applying the product fresh from the stable.

The manure shed has already been mentioned. A few dollars will build it. Sometimes a half barrel is sunken in the centre of the manure shed, and the drainage from the manure heaps collected there, and returned to the tops of the heaps. It is occasionally necessary to add water, when turning manure, to secure the desired degree of dampness and a gentle fermentation. This fermentation will cause the litter to fall to pieces, and will convert it into quickly-available plant food.

No one who has never tried it will expect the generous heaps which will follow systematic and persevering efforts to accumulate and stack up the available manure materials on any farm.

Preservatives.—The best-known common preservatives of manure in storage are gypsum, kainit and acid phosphate.

Gypsum or land plaster holds ammonia, and is thus of the highest value as a preservative. Gypsum must be moist to be effective, and, hence, should be used regularly upon the fresh manure.

Kainit, which is a low-grade sulphate of potash, checks fermentation, and hence prevents loss of ammonia. It contains much salt, and attracts and holds moisture. It should not be used under the feet of animals.

Acid phosphate contains much gypsum, and unites with ammonia that would otherwise escape.

The Geneva (N. Y.) Station recommends the use of one of the following per day:

The advantage of using kainit and acid phosphate are that they add potash and phosphoric acid respectively, in which barnyard manure is likely to be deficient. In some soils the potash will be preferable; in others, phosphoric acid will do more good.

Value of Manure of Each Kind of Animal.—It has been figured out that the average value of horse manure per year is $27 per animal; cattle, $19; hogs, $12; and sheep, $2. But these are not the only sources of manure on the farm. The hen-house will annually yield manure to the value of 25 to 50 cents per fowl, if intelligently cared for. The outhouse will produce fertility to the amount of $10 to $50 per year, according to the size of the family, the precautions as to loss by leaching, and the care given. The kitchen slops, including the scraps, are worth $10 to $25 per year, if properly composted. The wood ashes have a distinct and high fertilizing value; but not in the hen-house, where they are worse than wasted. And even coal ashes can be turned to account. Professor Roberts has suggested $250 per year as a conservative estimate of the value of the manure produced during seven winter months on a farm carrying four horses, twenty cows, fifty sheep and ten pigs. The estimated value may be made much higher in cases where farmers are willing to use thought and labor in preparation and preservation of home-made manures.

Solid Manure and Liquid Manure.—The urine is the most valuable portion of the excretion of animals, according to the tables of the agricultural chemists. It is especially rich in nitrogen, and, hence, its strong odor under fermentation. It is also rich in potash. Its place is on the manure heap, not in a ditch leading to a brook. If it collects in quantities beyond the absorbing power of the manure pile, it should go on the compost heap or else be diluted and at once put upon the land.

When to Fertilize.—The land is a good bank in which to deposit money in the form of manure; but there are certain portions of the year when the land bank declares no dividends. It is safe to put manure upon an unfrozen soil at any time, but the best, the quickest, and the largest results are obtained by manuring during the growing season, preferably just before planting the crop. Small applications, often repeated, are preferable to large, though rare, applications. Plants, like animals, consume small amounts of food each day, and cannot take a year's food at a single meal.

Humus.—Humus, often referred to by agricultural writers, is a name for decaying organic matter in the soil. Green crops turned under, grass roots, stubble, leaves, long manure, etc., form humus. The term is a comprehensive one. Humus is a dark-colored substance, abundant in all rich ground. A lump of manure that has been lying in the ground for a year or two has become, practically, a mass of humus.

Minute Soil Workers.—In all good soils there are myriads of small organisms, whose duty is to destroy organic matter and convert it into soil, or into humus, or into plant food.

This explains the superiority of good, moist soil as compared to coal ashes for making compost heaps. Coal ashes are worth sifting, if the work can be done automatically; that is, by simply pouring the ashes upon a sloping wire screen. The coarse portion of the ashes, if not worth reburning, will at least make good walks, drives or road beds, while the fine portions make excellent absorbents to put under hen roosts.

Hen manure and the product of the outhouse, whether containing sifted ashes or not, should go speedily into a heap of moist earth, for this earth will furnish the organisms to quickly convert the excreta into valuable soil. Sifted coal ashes usually contain some fertility on account of wood, garbage, etc., burned in the kitchen stove, but have value mainly as absorbents. Moist loam, on the other hand, teems with life, and has the wonderful ability not merely to hide organic matter, but to actually change its character, converting it into soil that retains none of its original characteristics. What was malodorous manure, offensive to smell and touch, is changed into an odorless, dark-colored material that leaves no stain upon the hands, and which is plant food of the best and most available character.

Economy in Manuring.—True economy in manuring demands a comprehension of these simple matters. The methods are inexpensive, and are within the reach of every tiller of the soil.

The whole matter may be summed up in a few words, as follows: Waste nothing, permit no fermentation or leaching, use preservatives, and learn the true art of making composts, including the functions of the minute organisms just described.

No better use can be made of rainy days in summer or winter than in caring for manure; turning the piles, making compact stacks, adding needed moisture and preservatives, shaking out all lumps and putting undecayed portions into the centre of the heap.

Ton after ton of the best kind of fertilizer can be accumulated on every farm in this manner, including not only what is now lost through careless handling, but also a large amount of good material that is now entirely overlooked on many farms. All rubbish, all litter, all dirt, has a fertilizing value. If certain waste products must go to the bonfire, the ashes can at least be saved and used during the next growing season. It is sometimes better to burn weeds and certain tough vines than to attempt to compost them; but the ashes should not be wasted. It is the saving of many little things that counts in the yearly total. Labor is money, but it is better to invest labor at home than to go to the fertilizer-maker for supplies and pay out cash.

The Fertilizer Man.—The fertilizer man will always be with us, because he has a true place in the economy of the farm and garden. We must go to him for the preservatives already mentioned—for gypsum, for kainit and for acid phosphate; and also for complete fertilizers. These articles are all comparatively cheap. The fertilizer man can make but modest profits upon them. The purchase of high-grade goods from well-known and honest makers is to be commended, for it is strictly economical.

The thing to be avoided is the blind buying of fertilizers from unknown or irresponsible makers or agents. This is worse than buying a cat in a bag, and results in great waste of good money. Wood Ashes.—Wood ashes is rich in potash, and is particularly valuable with potatoes, fruits of all kinds, etc. But it is a great error to mix wood ashes with fresh manure of any kind, especially with hen manure, as the escape of ammonia is hastened and much value is lost.

Natural and Artificial Manures.—Where the home supply of manure is insufficient for a piece of ground, necessitating the addition of artificial manure, it is universally conceded to be good practice to stretch the natural product over the whole tract and then to go over the whole tract with an artificial fertilizer.

Irrigation. [A]—In connection with a review of the home sources of manure the item of irrigation must not be overlooked, for it is thoroughly well established that water is a carrier of appreciable amounts of fertilizing materials. In European countries large areas of pasture and mowing lands are fertilized by water alone, the irrigation being regarded as of great value on this account, aside from the fact that it supplies moisture to the grass roots. Most streams in the United States contain more or less sewage, and in respect to irrigation are valuable on that account.

Waste Products.—Many waste or by-products, available for use as fertilizers, come from time to time within the reach of the farmer or gardener, especially to those living near towns or railroads.

The average market house, be it said with regret, is none too clean, and refuse in considerable amounts could be had there for the trouble of sweeping. Cattle cars often contain several inches of valuable droppings, to be had for next to nothing. Street-scrapings are worth the trouble of hauling, [Pg 18]
[Pg 19] if the distance is short. The manure lost on the highways is very great in amount, and may be worth the cost of collection. There will some day be a machine for gathering this manure from the roads by horse-power, as it would amply repay the expense of driving such a machine along every much-used highway.

Value of Manure.—Dr. Beal figures the values per ton of the several farm-made manures as follows: Hen manure, $7.07; sheep, $3.30; pigs, $3.29; horses, $2.21; cows, $2.02.

These figures are based on the assumption that the animals are well fed, and that no leaching of the manure is allowed, with gypsum used as a preservative, and good care exercised in all respects. It must not be supposed that all manure has such value, or that any manure will retain such value under careless treatment.

Green Manuring.—The system of green manuring, as formerly understood and practiced, had two purposes in view. One was to supply the soil with needed humus; the other to furnish winter protection and prevent washing. The practice is a very old one and has much to commend it. Not only do plant roots draw up fertility from considerable depths, to be afterward deposited in the superficial soil when the growing crop is turned down by the plow, but the process favors chemical changes in the soil by the admission of air and sunlight and by the decomposition of leaves, stems and roots. But nothing whatever in the way of new fertility is added by turning down a rye crop, for instance.

Cultivating the Legumes.—The present system of green manuring contemplates something in addition to what was formerly gained, for agricultural sciences now recognizes the fact that nitrogen, the most expensive element of fertility, can be taken from the air and added to the plant food in the soil by means of certain plants which have the peculiar habit of regularly forming little tubercles or lumps on their feeding roots. These lumps are to be found on plants in perfect health, and are not parasitical in any hostile sense. The lumps are filled with small living organisms called bacteria, and, hence, have been called bacteroid tubercles. The minute tenants slowly but surely secrete nitrogen, and put it in a form adapted to plant growth.

The plants which bear these root lumps belong to a group called legumes, of which clover, peas, beans, vetches, etc., are familiar examples.

Curiously enough, nearly all the leguminous plants are thus fitted by nature by means of the root lumps to act as soil enrichers, and these plants have, therefore, assumed the highest agricultural significance.

It is well known that such crops as cowpeas, crimson or scarlet clover, common red and pea vine or sapling clover, Soja beans, vetches, etc., can be used to add nitrogen to the soil in commercial quantities. The gain of new material, expressed in money, has been estimated as high as $25 per acre. This, therefore, is the avenue through which the farmer can most economically supply nitrogen to his land. If he will exercise all the economy heretofore suggested in the care of natural manures, and will grow legumes, he will not have much occasion to buy nitrogen in the market.

Grass vs. Clover.—An idea of the great fertilizing value of the leguminous plants as compared with grasses may be obtained by a study of the following analyses from U. S. Farmers' Bulletin No. 16, by Dr. E. W. Allen, on "Leguminous Plants for Green Manuring and for Feeding":

Nitrogen, Phosphoric Acid, Potash.—We have just noted the cheapest source of nitrogen. It can be collected by root tubercles at less than the commercial rate of 14 to 17 cents per pound.

Phosphoric acid can be best secured, if a new supply becomes necessary, in the form of ground bone or in the form of acid phosphate. Either of these articles, if bought from a reliable dealer, is a good and economical thing to use.

Potash is to be had most cheaply, perhaps, in the manner suggested heretofore: by the use of kainit as a preserver of stable manure. The kainit performs a double purpose if used in that way, and thus gets upon the land in a cheap manner.

Muriate of potash and sulphate of potash are high-priced articles, but when bought from good houses are fully worth the money they cost. Except for the use of kainit, just mentioned, the muriate or sulphate would be the more economical form.

Potash or phosphoric acid (or both), as may be determined by circumstances, are needed to aid crimson clover in its growth, and with the clover form a perfect manure.

Barnyard manure is a perfect fertilizer, especially when preserved with kainit or acid phosphate; and a leguminous crop, if stimulated with phosphoric acid and potash, leaves the land in fine cropping condition.

Value of Green Manures.—The cash value of green manuring is somewhat a matter of location. On light, sandy soils it will be found wise to turn the whole crop under with the plow, while on heavy loams this plan is of doubtful benefit. On the latter land it is conceded to be better practice to harvest the crop and feed it to stock, and return the resulting manure to the land.

Maximum Amounts of Manures.—Nobody has yet ventured to fix the maximum amounts of natural or artificial manures that soils will bear, but these amounts are great. Reference has already been made to the number of tons of stable manure per acre used respectively by market gardeners and farmers in America. As to commercial fertilizers, the quantity has been pushed up to two tons per acre, with enormous crops in consequence, and with no bad results where the constituent of the fertilizer were well balanced and where the water-supply was ample. It is quite easy, however, to scorch or burn the foliage of growing plants by the improper use of acid fertilizers in dry weather. Of course, no such amount as two tons per acre would be used in ordinary farming or farm gardening, but only in certain intense cultural operations.