In the United States no truffles of economic importance have thus far been found. One or two small species have been found during a single season in Minnesota, and small forms are also known in California. It is thought that none of the larger edible species are native in this country. There seems to be no reason why truffle-growing may not succeed in parts of some of the southern states. The introduction experiments thus far have been of no consequence.
Truffles are found in lime-containing clay soils, and are thought to be absent from all sandy soils. They are seldom found at great distances from the roots of certain trees, and it is thought that the mycelium is, in part at least, parasitic on living roots. T. melanosporum is more commonly found under oaks, particularly Quercus Iler, the live-oak (Cheue rent) of southern Europe, Q. coccifera, a scrub live-oak of the Mediterranean garigues, and Q. sessiliftora.
Properly speaking, truffles are exploited rather than cultivated ; nevertheless they are cultivated in the sense that many areas in which truffles did not grow are now yielding an abundance of this fungus. Truffle production has been made possible in such areas by planting the necessary shelter trees, providing for proper soil drainage and shut ing out predatory animals. Sometimes, moreover, the soil from truffle regions has been spread on the land, thus securing a sewing of the spores. A double economic purpose has thus been accom plished.—reforestation and the encouragement of t rutHe-growing.
T,rfa. Terle:iacecr. Fig. 711.
The terfas. or kameS, are fungi which in general appearance resemble the white truffle of southern Europe, but because of well-marked characters they are placed in another related family, the Ter jeziorefr. They were among the earliest known edible fungi, and were greatly prized by the an cient Greeks. At present the terfas are abundant in parts of Asiatic Turkey and Persia, particularly near Smyrna and Babylon, also in the Libyan Des ert of northern Africa and in the semi-desertic regions of southern and southwestern Algeria. They are highly prized by the Arabs, and wher ever they occur in quantity they constitute an important food product. These fungi are found, as a rule, under certain species of Cistacmr, although they occur associated with the roots of other plants. They are found more readily than truffles. They mature in the spring after the heavy rains, and as they develop rapidly, they break or raise the soil slightly, so that the locations may be detected, although subterranean. They occur in
lime- containing, sandy soils, mostly in the flood plains of small streams. The production of these fungi is very evidently dependent on sufficient winter rainfall, or inundations at some time in the winter months.
Tuekahoe. (Indian Bread, Indian Loaf. Okeepe nauk of the early Indians.) Fig. 713.
The American tuckahoe is now considered to be inedible. It is unquestionably the sclerotial stage of some fungus, very probably of a pore-bearing mushroom (supposedly of a Polyporus). The form and size of this sclerotium is not unlike a coco nut. The exterior is also rough and bark-like. The interior, however, when mature, is hard, white and friable. The tuckahoe has been found in various parts of the South and Southwest. It has received tentatively the name Pachyma eoeos.
Among other pore-bearing mushrooms which may produce a somewhat similar sclerotial stage, one of the most interesting is Polyporus The sclerotium of this fungus is known as "Native Bread," and is said to be eaten by the native in habitants. P. Sapurema, found in Brazil, produces a sclerotium weighing many kilos. In Italy, P. tuberaster, produces a sclerotial mass of mycelium. This mass will produce the edible sporophores of the Polyporus until the stored-up nutriment is ex hausted. The sclerotial mass is therefore sought in the open and brought in, so that none of the mushrooms may be lost as produced. No form of tuckahoe or allied structure is cultivated so far as can be ascertained.
Literature on mushrooms.
Atkinson, Mushrooms, Edible, Poisonous, etc., first edition, Andrus and Church, Ithaca, N. Y. (1901); second edition, Henry Holt & Co., New York City (1903); B. M. Duggar, The Principles of Mushroom-Growing and Mushroom Spawn Making, Bulletin No. 85. Bureau of Plant Industry, United States Department of Agriculture (1905); W. G. Farlow, Some Edible and Poisonous Fungi, Bulletin No. 15, Division of Vegetable Physiology and Pathology, United States Department of Agricul ture (1898); Wm. Hamilton Gibson, Our Edible Toadstools and Mushrooms, and How to Distinguish Them, Harper & Bros., New York (1895); Nina L. Marshall, The Mushroom Book, Doubleday, Page & Co. (1901); Charles McIlvaine, One Thousand American Fungi, Bowen-Merrill Co., Indianapolis, Ind.; Charles H. Peck, Reports of New York State Botanist in the Reports of the New York State Museum of Natural History, 1879 to present.