George E. Waring

What principles should regulate us in composting?

In what condition is solid dung of value as a fertilizer?

What do we aim to do in composting?

In composting stable manure in the most economical manner, the evaporation of the organic parts and the leaching of the ashy (and other) portions must be avoided, while the condition of the mass is such as to admit of the perfect decomposition of the manure.

Solid manures in their fresh state are of but very little use to plants. It is only as they are decomposed, and have their nitrogen turned into ammonia, and their other ingredients resolved into the condition required by plants, that they are of much value as fertilizers. We have seen that, if this decomposition takes place without proper precautions being made, the most valuable parts of the manure would be lost. Nor would it be prudent to keep manures from decomposing until they are applied to the soil, for then they are not immediately ready for use, and time is lost. By composting, we aim to save every thing while we prepare the manures for immediate use.

SHELTER.

The first consideration in preparing for composting, is to provide proper shelter. This may be done either by means of a shed or by arranging a cellar under the stables, or in any other manner that may be dictated by circumstances. It is no doubt better to have the manure shed enclosed so as to make it an effectual protection; this however is not absolutely necessary if the roof project far enough over the compost to shelter it from the sun's rays and from driving rains.

The importance of some protection of this kind, is evident from what has already been said, and indeed it is impossible to make an economical use of manures without it. The trifling cost of building a shed, or preparing a cellar, is amply repaid in the benefit resulting from their uses.

THE FLOOR.

The floor or foundation on which to build the compost deserves some consideration. It may be of plank tightly fitted, a hard bed of clay, or better, a cemented surface. Whatever material is used in its construction (and stiff clay mixed with water and beaten compactly down answers an excellent purpose), the floor must have such an inclination as will cause it to discharge water only at one point. That is, one part of the edge must be lower than the rest of the floor, which must be so shaped that water will run towards this point from every part of it; then—the floor being water-tight—all of the liquids of the compost may be collected in a

TANK.

This tank used to collect the liquids of the manure may be made by sinking a barrel or hogshead (according to the size of the heap) in the ground at the point where it is required, or in any other convenient manner.

In the tank a pump of cheap construction may be placed, to raise the liquid to a sufficient height to be conveyed by a trough to the centre of the heap, and there distributed by means of a perforated board with raised edges, and long enough to reach across the heap in any direction. By altering the position of this board, the liquid may be carried evenly over the whole mass.

The appearance of the apparatus required for composting, and the compost laid up, may be better shown by the following figure.

The compost is made by laying on the floor ten or twelve inches of muck, and on that a few inches of manure, then another heavy layer of muck, and another of manure, continuing in this manner until the heap is raised to the required height, always having a thick layer of muck at the top.

After laying up the heap, the tank should be filled with liquid manure from the stables, slops from the house, soap-suds, or other water containing fertilizing matter, to be pumped over the mass. There should be enough of the liquid to saturate the heap and filter through to fill the tank twice a week, at which intervals it should be again pumped up, thus continually being passed through the manure. This liquid should not be changed, as it contains much soluble manure. Should the liquid manures named above not be sufficient, the quantity may be increased by the use of rain-water. That falling during the first ten minutes of a shower is the best, as it contains much ammonia.

The effects produced by frequently watering the compost is one of the greatest advantages of this system.

The soluble portions of the manure are equally diffused through every part of the heap.

Should the heat of fermentation be too great, the watering will reduce it.

When the compost is saturated with water, the air is driven out; and, as the water subsides, fresh air enters and takes its place. This fresh air contains oxygen, which assists in the decomposition of the manure.

In short, the watering does all the work of forking over by hand much better and much more cheaply.

At the end of a month or more, this compost will be ready for use. The layers in the manure will have disappeared, the whole mass having become of a uniform character, highly fertilizing, and ready to be immediately used by plants.

It may be applied to the soil, either as a top-dressing, or otherwise, without fear of loss, as the muck will retain all of the gases which would otherwise evaporate.

The cost and trouble of the foregoing system of composting are trifling compared with its advantages. The quantity of the manure is much increased, and its quality improved. The health of the animals is secured by the retention of those gases, which, when allowed to escape, render impure the air which they have to breathe.

The cleanliness of the stable and yard is much advanced as the effete matters, which would otherwise litter them, are carefully removed to the compost.

As an instance of the profit of composting, it may be stated that Prof. Mapes has decomposed ninety-two cords of swamp muck, with four hundred bushels of the lime and salt mixture, and then composted it with eight cords of fresh horse dung, making one hundred cords of manure fully equal to the same amount of stable-manure alone, which has lain one year exposed to the weather. Indeed one cord of muck well decomposed, and containing the chlorine lime and soda of four bushels of the mixture, is of itself equal in value to the same amount of manure which has lain in an open barn-yard during the heat and rain of one season, and is then applied to the land in a raw or undecomposed state.

The foregoing system of composting is the best that has yet been suggested for making use of solid manures. Many other methods may be adopted when circumstances will not admit of so much attention. It is a common and excellent practice to throw prepared muck into the cellar under the stables, to be mixed and turned over with the manure by swine. In other cases the manures are kept in the yard, and are covered with a thin layer of muck every morning. The principle which renders these systems beneficial is the absorbent power of charcoal.

LIQUID MANURE.

Liquid manure from animals may, also, be made useful by the assistance of prepared muck. Where a tank is used in composting, the liquids from the stable may all be employed to supply moisture to the heap; but where any system is adopted, not requiring liquids, the urine may be applied to muck heaps, and then allowed to ferment. Fermentation is necessary in urine as well as in solid dung, before it is very active as a manure. Urine, as will be recollected, contains nitrogen and forms ammonia on fermentation.

It is a very good plan to dig out the bottoms of the stalls in a circular or gutter-like form, three or four feet deep in the middle, cement the ground, or make it nearly water-tight, by a plastering of stiff clay, and fill them up with prepared muck. The appearance of a cross section of the floor thus arranged would be as follows:

The prepared muck in the bottom of the stalls would absorb the urine as soon as voided, while yet warm with the animal heat, and receive heat from the animal's body while lying down at night. This heat will hasten the decomposition of the urea,[AA] and if the muck be renewed twice a month, and that which is removed composted under cover, it will be found a most prolific source of good manure. In Flanders, the liquid manure of a cow is considered worth $10 per year, and it is not less valuable here. As was stated in the early part of this section, the inorganic (or mineral) matter contained in urine, is soluble, and consequently is immediately useful as food for plants.

By referring to the analysis of liquid and solid manure, in section V., their relative value may be seen.