Before making the beds, while the material is in preparation, all particles of old wood, twigs, &c., that are found in the manure should be removed, as indeed should any extraneous matters likely to prove offensive or useless.
The best time for making mushroom-beds, where they are not regularly made in succession throughout the autumn and winter months, as they ought to be where there is abundance of material and a good mushroom-house, is in August and September, as in the early autumn months the natural heat is sufficient to cause the spawn to germinate freely, and beds made then ought to bear freely before and up to Christmas, and during autumn.
When making the bed, the chief object to bear in mind is the equal placing of the material. It should be well mixed and regularly and firmly placed so that the whole may be of a similar texture. Some heavily tramp and pound their beds to secure firmness; moderately done this is beneficial; thoroughly equable pressure with the fork, when the fork can be used, will with the pressure of firm earthing be sufficient; when beds are made on elevated benches in boxes, and in all positions where but a slight body of material is used, and where firmness cannot result from the general pressure of the mass, some kind of pressure with a wooden mallet or the like must be employed.
The beds once made, we next arrive at the spawning, and will first inquire, What is spawn?
CHAPTER III.
MUSHROOM-SPAWN.
The first thing we have to determine is, What is spawn? Generally, the spawn, or what in scientific language is called the mycelium, is supposed to be analogous to seed, while it really is what may be termed the vegetation of the plant, or something analogous to roots, stems, and leaves of ordinary plants, the visible part or stem, head and gills, of the mushroom being, in fact, the fructification, though in such an apparent preponderance to the other parts. A knowledge of the anatomy and life-history of the mushroom is not necessary to the cultivator, and is not familiar even to those who make of mushrooms a study. We know that the gills are simply surfaces on which germs or spores are produced. The membrane that covers the spore plates of a single mushroom would cover a large space if spread out, and the spores are counted by myriads. We can see them clearly enough under the microscope—can see in what manner they are borne on and fixed to the gills; but of the history of their lives, from the time they fall from the surfaces on which they were born, till the “young mushroom” or inflorescence is vigorously pushing up from the mass of delicate vegetation which they have given rise to in earth or decaying manure, we know nothing. However, the preparation of the spawn, and the subsequent management of it in the mushroom-bed, are the matters which really concern us.
How is spawn obtained in the first instance? It is found in a natural state in half-decomposed manure-heaps, in places where horse-droppings have accumulated and been kept dry, in riding-schools, sheds to which horses have long had access, in “mill tracks” under cover, in pastures, in partially decayed hotbeds, &c., and rarely or never in very moist or saturated materials. This spawn, sometimes termed “natural” in this country, and called by the French “virgin spawn,” is the best that can be obtained, and should be used in preference wherever it can be found. To use it, all that has to be done is to divide the material permeated by the white spawn into pieces a few inches square, and say an inch or more thick. They will of course break up irregularly, but all should be used, whether of the size of a bean, or nearly that of the open hand. Then they are inserted into the surface of the mushroom-beds in the ordinary way.