The beds under the greenhouse benches may be made up in the same way as are beds anywhere else; that is, flat upon the floor and between two boards set on edge, as seen in Fig. 16, or in ridges under the high or middle benches, as in Fig. 17, or in banked beds against the back wall, as shown in Fig. 18. Generally the flat bed is the most convenient to make and take care of.
Fig. 18. Banked Bed against a Wall.
In open, airy greenhouses it is always well to inclose the mushroom beds in box casings and with sash or shutter coverings, to prevent draughts and fluctuations of temperature and atmospheric moisture. This can easily be done by making the sides a board and a half (fifteen inches), or two boards (twenty inches) high, and covering over with light wooden shutters, sashes, or muslin or paper-covered light frames. See [Fig. 11.]
Ammonia Arising.—Ammonia arising from the manure of the mushroom beds in the greenhouse may be injurious to the other inmates of the greenhouse. If the manure has been well prepared before it was introduced into the greenhouse, the ammonia arising from it will not, in the least degree, injure any other plants or flowers that may be in the house; but if the manure is fresh, hot, and rank, the opposite will be the case. Beds in greenhouses should always be made up of manure that has been well prepared beforehand out of doors or in a shed, and as it is brought into the greenhouse it should at once be built solidly into the beds. Then very little steam will arise from the beds; in fact, it will be imperceptible to sight or smell.
CHAPTER VI.
GROWING MUSHROOMS IN THE FIELDS.
Under suitable conditions we can grow mushrooms easily and abundantly in the open fields, and the planting of the spawn is all the trouble they will cause us. During the late summer and fall months mushrooms often appear spontaneously and in great quantity in our open pastures, but in their natural condition they are an uncertain crop, as in one year they may occur in the greatest abundance, and in the next perhaps none can be found in the fields in which they had been so numerous the previous year. Why this should be so is not very clear. The popular opinion is that after a dry summer mushrooms abound in the fields, but after a wet summer they are a very scarce crop; and the inference is that the moisture has killed the spawn in the ground. This may be true to a certain extent, but how does it happen—as it certainly often does—that good spawn planted by hand in the fields in early summer will produce mushrooms toward fall no matter whether the summer has been wet or dry? At the same time, it is true that a wet spell immediately succeeding the planting of the spawn will kill a great deal of it.
As a rule, wild mushrooms abound most in rich, old, well-drained, rolling pasture lands, and avoid dry, sandy, or wet places, or the neighborhood of trees and bushes. In attempting to cultivate them in the open fields we should endeavor to provide similar conditions. Then the chief requisite is good spawn, for without this we can not raise mushrooms.