The Covered Yard.—If the possible value of manure were realized, provision for its care would be made as promptly and surely as provision for the care of a harvested crop. There are only three conditions that must be provided in order that manure may be preserved without much loss. The manure must be protected from leaching rains, it must be kept moist, and air must be excluded. The exposure of stable manure to the processes of fermentation and leaching, produces a waste that is believed to amount to several hundreds of millions of dollars in the United States annually. The day will come when no farmer will be willing to share heavily in a loss from this source, but will either spread manure fast as made or provide a roof for the stored manure. An absolutely tight floor is not so great a necessity as it is in the stable, because the amount of moisture is under control, but many farmers prefer to make concrete floors for the manure-shed and thus to guard against any loss from leaching. The chief cost may be confined to the roof.
A better plan is to inclose three sides, making them so tight that all drafts will be prevented, and to use the shed as a place of exercise for cows or other livestock. We have learned within recent years that such an inclosure is more healthful and comfortable for cattle than stalls in an inclosed building, no matter how cold the weather may be. The fresh air without any drafts, and the liberty of movement, are needed. This shed should be connected with the stable, and on its floor the manure from the stables may be spread daily. It should be scattered evenly over the surface, and the mass can be kept firm by the tramping of the animals. It may be necessary to add some water at intervals to keep the mass sufficiently moist. The water excludes air and assists in holding harmful fermentation in check.
Harmless Fermentation.—There is a kind of fermentation in manure that goes on in the absence of air. It is due to bacteria that break up the organic matter, producing rotted manure. This is not attended by much loss, and proceeds beneath the surface of the moist and packed mass. Manure properly controlled under a roof goes into prime condition for spreading later in the season. The only danger is neglect, and especially when the livestock is removed to the pasture fields in the spring. If no water is added from time to time, hot fermentation replaces the harmless kind because air can penetrate through the bed of manure. Compactness and moisture can save the plant-food with small loss throughout the summer, and a body of good manure is available when needed for top-dressing land in the summer.
Rotted Manure.—Mixed stable manure contains in a ton as many pounds of potash as it does of nitrogen, and yet we speak of it as a highly nitrogenous fertilizer. When fresh manure has suffered no loss of the liquid part, much of its nitrogen is almost immediately available. The nitrogen in the urine is in soluble forms, and fermentation quickly occurs. When manure is used on grass, it cannot be too fresh, as the immediate action of the nitrogen is desirable. Vegetable growers often prefer a slower and more continuous action, and the rotting of manure under right conditions changes the liquid nitrogen into compounds that act more slowly.
The solid material in horse manure contains less water than that of the cow, and this absence of water permits quick fermentation when air is present. The use of large quantities of such manure per acre is not liked by vegetable-growers. Rotting under control in a covered barnyard has a beneficial effect for this reason when a hot manure is not wanted. The covered shed costs some money, and there is a loss estimated at 10 per cent under the best conditions, but when manure cannot be drawn fast as made, there is compensation in improved condition for certain soils and crops.
Composts.—The compost, involving the handling of manure and soil, has no rightful place on the average farm. The gardener or trucker using great quantities of manure per acre must let some of the fermentation occur before he incorporates it with the soil, or harm will result. He wants reduction in volume, and such change in character that it will add to the retentive character of the soil respecting moisture instead of drying the soil out. He can afford all the labor of piling the manure with layers of sods or other material, and the turning to secure mixing. It is his business to watch it so that loss will not occur.
The farmer uses manure in smaller quantities per acre. Probably all his fields need the full action of the organic matter in its rotting. The percentage of humus-making material is low. The place for fresh manure is on the land, when this is feasible. The covered shed is a device for holding manure with least possible loss when spreading cannot be done, or a supply must be carried over for land in the summer. The gain in condition is only incidental, and an advantage chiefly to vegetables. The composting of manure by gardeners is not a practice to be copied on most farms.
Poultry Manure.—The value of poultry manure often is overestimated. Its content of plant-food is one half greater than that of horse manure, ton for ton. The availability of the nitrogen is so great that returns from applications are immediate, and give the impression of greater strength than is possessed. Its availability makes it excellent for plants that need forcing. For such use it needs reënforcing only with acid phosphate, but as a general manure it should have the addition of potash. Acid phosphate should be used in the poultry-house to prevent loss of nitrogen, which escapes quickly on account of rapid fermentation, and to supply phosphoric acid. Thirty pounds of acid phosphate to each 100 pounds of the manure gives a mixture containing one pound of nitrogen, three pounds of phosphoric acid, and two fifths of a pound of potash. The addition of four pounds of muriate of potash makes the mixture a well-balanced and effective fertilizer when used at the rate of 500 to 1000 pounds per acre. Dry muck or loam should be mixed with it to serve as an absorbent and to give good physical condition.
CHAPTER XIV