Agaricus campestris. To produce mushrooms artificially,beds variously constructed are employed.

Times Of Forming The Beds

Beds may be constructed from January until the beginning of May, for spring and summer production; and from July to the close of the year, for autumn and winter. Construction. - A bed is usually constructed of stable dung, etc, prepared as already directed for cucumbers. It is made in the form of the roof of a house, four or five feet wide at the base, narrowing to an apex, which should be rather rounded, three or four feet high, and the length from ten to fifty feet. The dung being laid in alternate rows, with clayey loam, from which the largest stones have been sorted; each layer of dung to be a foot thick, and of loam four inches, so that three layers of each will be sufficient to complete the requisite height. The dung must be well separated and mixed, and beat, but not trod down. When completed, the bed must be covered with litter or other light covering, to keep out the wet, as well as to prevent its drying; clean dry straw will do, but sweet hay, or matting, is to be preferred.

Situation

The bed should be made in a dry sheltered situation, and on the level ground in preference to founding it in a trench, which prevents the spawning being performed completely at the bottom, and guards against the settling of water, which may chill it. If the site is not dry, it must be covered with stones, clinkers, etc, to act as a drain; for nothing destroys mushrooms sooner than excessive moisture, except an extreme of heat or cold. To obviate the occurrence of these unfavourable circumstances, it is by far more preferable to construct it under a shed. If it is constructed in a shed, it may be built against one side, sloping downwards from it. To proceed with greater certainty during the winter, a fire flue may pass beneath the bed; but it is by no means absolutely necessary, for by the due regulation of covering, it may always he kept of sufficient temperature.

Management

The spawn must not be inserted before the temperature has become moderate.

Temperature

The minimum is 50°, and the maximum 65°. Insert the spawn as soon as the violence of the heat has abated, which it will in two or three weeks, though sometimes it will subside in eight or ten days.

Spawning

The large lumps of spawn, being broken into moderately small pieces, are to be planted on both sides of the bed and ends, if it is hipped; each fragment just beneath the surface of the dung, in rows sis or eight inches apart each way. Some gardeners erroneously scatter the spawn irregular-' ly over the surface. Fine rich loam, rather light than otherwise, is then to be put on, two inches deep, the stones being carefully separated. Some gardeners, endeavouring to imitate the natural mode of growth, spread an inch in depth of mould over the beds, in which they set the spawn, and gently cover it | with half an inch more. Others lay a ledge of mould, four inches high, and two thick, all round the bed; upon this close to the dung, they lay the spawn; then a second ledge, six inches, of similar thickness, on this they set another row of spawn, and so proceed until the bed is finished; but this has no advantage over the first mode described, and is much more tedious. Lastly, a covering of straw, six or twelve inches thick, according to the temperature, is to be laid on, and continued constantly. When the earthing is finished, the surface must be gently smoothed with the back of the spade, which fixes it properly, and if in the open air throws off' any excessive rain.

If, after the bed has been spawned and covered up, the heat appears to be renewed in any considerable degree, the greatest part of the covering must be removed, but restored again during rain, if the bed is not under cover; and to guard against this contingency it is a good practice to mould over only two-thirds of the bed at first, leaving the top uncovered to serve as a vent for the heat and steam, but when all danger is passed it may then be completed.

Mr. Haukin, gardener to Capt. Nut-ford, thus completes his preparations: - "In about a week or ten days afterwards, I finish off the beds with green turf, one inch and a half in thickness, making the beds in my boxes, in all about nine inches in depth. I beat down the turf very firmly with the back of a spade; in finishing afterwards, I have no farther trouble except in paying attention to the fire, and in admitting fresh air as it may be required. The house is heated by open tanks, which run through the centre of it, and which return again into the boiler, giving out a sufficient quantity of moisture for the necessary development and growth of the mushroom. During night, the grassy turf becomes copiously loaded with moisture; and should the following day prove fine, I never omit giving abundance of fresh air by the doorway. The temperature of the house ranges from 60° to 65° during the day, and at night it is frequently allowed to fall as low as temperate.

"The great advantage of growing the mushroom upon fresh grassy turf is obvious to any one accustomed to its cultivation. I have been in the habit of growing it, and with great success, upon coal refuse for the last two years; and at present I have two boxes at work, one covered with coal dust, the other with turf; the produce of these shows the relative advantage of the two methods, for although those from the coal dust are large and of good flavour, they are decidedly inferior in both respects to those produced by the grass covered beds; indeed, such is the superiority of the latter, that if the mushrooms from both beds were gathered, and mixed indiscriminately, any one could, without difficulty, select those grown upon the turf from those raised on the beds covered with the small coal." - Gard. Chron.

In four or five weeks after spawning, in spring and autumn, the bed should begin to produce, but not until much later in summer and winter; and if kept dry and warm, will continue to do so for several months.

A gathering may take place two or three times a week, according to the productiveness of the bed. It sometimes happens that beds will not come into production for five or six months; they should not therefore be impatiently destroyed.