MUSHROOM, a popular term loosely ap plied to many species of higher fungi, especially such as have a cap (pileus) upon an erect stalk. Primarily, the mushroom is Agaricus campestris (see FUNGI), the only species cultivated upon a commercial scale. Though more than 700 spe des of mushrooms have been proved edible within the last half century, and though many others will doubtless be proved harmless, the novice should be cautious in trying new species. Each unfamiliar kind should be subjected to rigid examination first by smell, and malodorous ones discarded; then by taste, a small piece being nibbled but not swallowed. If no ill re sults follow in the course of several hours, a small piece may be swallowed. If no evil effects follow, but the flavor raw is unpleasant, cooked morsels may be cautiously tried, and results noted. Each individual must decide what species agree with hiin, because some systems will not endure kinds innocuous to others. Nervous fear of fancied bad symptoms must be con trolled, or real illness may be induced by the imagination.
Several species are popularly reputed viru lent which do not produce any marked effect upon the health for several hours, and which are widely feared as deadly. Since the two commonest of these (Amanita muscaria and A. phailoides) are often mistaken for the common mushroom, the novice should never gather any toadstools in the woods under the impression that they are the proper mushroom, which grows in pastures, lawns, etc., and not in shady places. Further, all species with yellow or white gills should be avoided until known to be edible. The common mushroom has pink gills when young, and purplish-brown or black gills when mature.
Several of the thousand species of the genus Agaricus are valued for food, but the common mushroom (A. campestris) is the most import ant. It is occasionally found in open and grassy glades; never in the deep forest, but most frequently in old pastures and lawns, especially in autumn, but often when conditions are favorable during the summer. It grows
about three inches tall, has a fleshy cap about three inches broad, generally white, sometimes reddish or brownish above and pink beneath. Its stem does not rise from a cup-like base as does that of Amanita phalloides. It is generally gathered in the °button" stage, that is, before the cap has expanded. Among its near relatives the best known is probably the horse mushroom (A. arvensis) which is much larger, whiter above, lighter below, the gills being white when young, but otherwise resembling the common species.
Success in mushroom growing seems to de pend more upon the individual grower than 'upon the method, since two growers may each succeed equally with very different methods. The essentials seem to be decaying organic matter in abundance, uniform but not excessive moisture and equable rather low temperature. The most popular places for cultivating this plant are caves, abandoned mines and quarries, cellars, pits and similar places, where the tem perature is naturally suitable or may be arti ficially controlled. The beds are usually made by spreading a layer of well-rotted manure and loam over a firmly packed deep layer of fresh horse-manure. After the violent heat of fer mentation has passed and the temperature has fallen to' or below 90° F., the mushroom °spawn" is planted. This spawn consists of the mycelium of the fungus in bricks (English) or flakes (French) made of equal parts of horse and cow manure and loam; it is a commercial article and its manufacture constitutes a busi ness distinct from mushroom growing. After sowing, the bed is kept moist by mulching with straw or covering with mats which are replaced in about 10 days with a layer of loam about two inches deep. In America the mushroom is rarely cultivated out of doors; in Europe it often is, the temperature and moisture there more favorable. It is frequently found growing wild in sufficient quantities to make commercial shipments profitable.