Chapter XXII

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Since the artificial cultivation of mushrooms for food is becoming quite an industry in this country with some, the following chapter is devoted to a treatment of the subject. Mention may be made here, however, of the attempts in parts of France to cultivate truffles, species of subterranean fungi belonging to the ascomycetes (various species of the genus _Tuber_). It had long been observed that truffles grow in regions forested by certain trees, as the oak, beech, hornbeam, etc. Efforts were made to increase the production of truffles by planting certain regions to these trees. Especially in certain calcareous districts of France (see Cooke, Fungi, etc., p. 260) young plantations of oak, beech, or beech and fir, after the lapse of a few years, produced truffles. The spores of the truffles are in the soil, and the mycelium seems to maintain some symbiotic relation with the roots of the young trees, which results in the increase in the production of the fruit bodies. Dogs and pigs are employed in the collection of truffles from the ground.

Comparatively few of the truffles, or other subterranean fungi, have been found in America, owing probably to their subterranean habit, where they are not readily observed, and to the necessity of special search to find them. In California, however, Dr. Harkness (Proc. Calif. Acad. Sci.) has collected a large number of species and genera. Recently (Shear. Asa Gray Bull. 7: 118, 1899) reports finding a "truffle" (_Terfezia oligosperma_ Tul.) in Maryland, and _T. leonis_ occurs in Louisiana.

FOOTNOTES:

[C] There is not room here to discuss the uses of other fungi than the "mushrooms."

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