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Preparation of the manure.

Get as good a quality of fresh horse manure as you can, and in sufficient quantity for the amount of bed or beds you wish to make. Next get it into suitable condition for making up into beds. This can be done out of doors or under cover of a shed, but preferably in the shed. Out of doors the manure is under the drying influence of sun and wind, and it is also liable to become over-wetted by rain, but under cover we have full control of its condition. All the manure for beds between July and the end of October is prepared out of doors on a dry piece of ground, but what is used after the first of November, all through the winter, is handled in a shed open to the south. During the autumn months we get along very well with it out of doors; after every turning cover the heap with strawy litter to save it from the drying influences of sun and wind. Remove this covering when next turned, and lay light wooden shutters on top of it as a precaution against rain. In the shed in winter the manure is protected against rain and snow and we can always work it conveniently; when the shed is open to the south as wagon and wood-sheds often are we get the benefit of the warm sunshine in the daytime in starting fermentation in the manure, but in the event of dull, cold weather, cover up the pile quite snugly with straw and shutters to start the heat in it. Altogether, a warm, close shed would be better.

It seldom happens that one can get all the manure he wants at one time; it accumulates by degrees. This is the case with the market grower who uses many tons, and hauls it home from the city stables a little at a time; also with the private grower, who uses only a few bushels or half a cord, and has it accumulate for days or weeks from his own stable. As the manure accumulates throw it into a pile, straw and all, but not into such a big pile that it will heat violently; and particularly observe that it shall not “fire-fang” or “burn” in the heap. If it shows any tendency to do this, turn it over loosely, sprinkle it freely with water, spread it out a little, and after a few hours, or when it has cooled off nicely, throw it up into a pile again and tread it firmly to keep it moist and from heating hastily.

When enough manure has accumulated for a bed, prepare it in the following way: Turn it over, shaking it up loosely and mixing it all well together. Throw aside the dry, strawy part, also any white “burnt” manure that may be in it, and all extraneous matter, as sticks, stones, old tins, bones, leather straps, rags, scraps of iron, or such other trash as we usually find in manure heaps, but do not throw out any of the wet straw; indeed, we should aim to retain all the straw that has been well wetted in the stable. If the manure is too dry do not hesitate to sprinkle it freely with water, and it will take a good deal of water to well moisten a heap of dry manure. Then throw it into a compact oblong pile about three or four feet high, and tread it down a little. This is to prevent hasty and violent heating and “burning,” for firmly packed manure does not heat up so readily or whiten so quickly as does a pile loosely thrown together. Leave it undisturbed until fermentation has started briskly, which in early fall may be in two or three days, or in winter in six to ten days, then turn it over again, shaking it up thoroughly and loosely and keeping what was outside before inside now, and what was inside before toward the outside now; and if there are any unduly dry parts moisten them as you go along. Trim up the heap into the same shape as you had before, and again tread it down firmly. This compacting of the pile at every turning reduces the number of required turnings. When hot manure is turned and thrown loosely into a pile it regains its great heat so rapidly that it will need turning again within twenty-four hours, in order to save it from burning, and all practical men know that at every turning ammonia is wasted, the most potent food of the mushroom. We should therefore endeavor to get along with as few turnings as possible; at the same time, never allow any part of the manure to burn, even if we have to turn the heap every day. These turnings should be continued until the manure has lost its tendency to heat violently, and its hot, rank smell is gone, usually in about three weeks’ time. If the manure, or any part of it, is too dry at any turning, the dry part should be sprinkled with water and kept in the middle of the heap. Plain water is what is generally used for moistening the manure, but I sometimes use liquid from the stable tanks, which not only answers the purpose of wetting the dry materials, but it also is a powerful stimulant and welcome addition to the manure. But the greatest vigilance should be observed to guard against overmoistening the manure; far better fail on the side of dryness than on that of wetness.

If the manure is too wet to begin with it should be spread out thinly and loosely and exposed to sun and wind, if practicable, to dry. Drying by exposure in this way is not as enervating as “burning” in a hot pile, and better have recourse to any method of drying the manure than use it wet. If, on account of the weather or lack of convenience for drying, the manure can not be dried enough, add dry loam, dry sand, dry half-rotted leaves, dry peat moss, dry chaff, or dry finely cut hay or straw, and mix together.

The proper condition of the manure, as regards dryness or moistness, can readily be known by handling it. Take a handful of the manure and squeeze it tight; it should be unctuous enough to hold together in a lump, and so dry that you can not squeeze a drop of water out of it.

Some private gardeners in England lay particular stress upon collecting the fresh droppings at the stables every day, and spreading them out upon a shed or barn floor to dry, and in this way keeping them dry and from heating until enough has accumulated for a bed, when the bed is made up entirely of this material, or of part of this and part of loam. But market gardeners, the ones whose bread and butter depend upon the crops they raise, never practice this method, and that patriarch in the business, Richard Gilbert, denounces the practice unstintedly.

Different growers have different ideas of preparing manure for mushroom beds, but the aim of all is to get it into the best possible condition with the least labor and expense, and to guard against depriving it of any more ammonia than can be helped. See Mr. Gardner’s method of preparing manure, .

Loam and Manure Mixed.- Mushroom beds are often formed of loam and manure mixed together, say one-third or one-fourth part of the whole being loam, and the other two-thirds or three-fourths manure; if a larger proportion of loam is used it will render the beds rather cold unless they are made unusually deep. I am not prepared to affirm or deny that this mixed material has any advantages over plain manure; I use it considerably every year and with good results; at the same time, I get as good crops from the plain manure beds. But it has many warm friends who are excellent growers.

In preparing this mixed material I use fresh sod loam well chopped up, and add it to the manure in this way: First select the manure and throw it into a heap to ferment, as before explained; then after the first turning cover the heap with a layer of this loam about three or four inches thick, enough to arrest the steam; at the next turning mix this casing of loam with the manure, and when the heap is squared off add another coating of loam of the same thickness in the same way as before, and so on at each turning until the whole mass is fit for use, and the full complement of loam, say one-fourth the full bulk, has been added. In this way much of the ammonia that otherwise would be evaporated from the manure is arrested and retained.

Some growers, when they first shake out their fresh manure, add the full complement of loam to it at once and mix them together. Others, again, Mr. Denton, of Woodhaven, for instance, prepare the manure in the ordinary way and when ready for use add the quota of loam. I use good sod loam for two reasons, namely, because it is the very best that can be used for the purpose, and, also, after being used in the mushroom beds it is a capital material, and in fine condition for use in potting soft-wooded plants. But the loam commonly used to mix with the manure is ordinary field soil. If the loam is ordinarily moist to begin with, and also the manure, there is very little likelihood of any of the material getting too dry during the preparation. And much less preparation is needed, for the presence of the loam lessens, considerably, the probability of hasty, violent fermentation.

Mr. Withington, of South Amboy, N. J., uses rather a stinted amount of loam in his manure. He writes me: “We made up our beds this year with a proportion of loam in the manure, say one part loam to eight parts manure, but have always used clear manure heretofore, and I think the beds hold out longer than when only manure is used.”