|California Fungi—Agaricus bitorquis
(Photo: © Fred Stevens)
Syll. Fung. 5:998. 1887.
Cap 5-15 cm broad, convex, becoming broadly so in age, sometimes expanding to plane with an upturned margin; surface smooth, whitish, often with adhering dirt; flesh white, thick, firm, unchanging; odor and taste mild.
Gills free, close, pallid, becoming pale brown, blackish-brown at maturity.
Stipe 4-10 cm long, 2-4 cm thick, stout, equal to enlarged below, solid; surface whitish, more or less smooth, sometimes with fine, appressed scales at the apex; veil membranous, thick, white, sheathing from the base of the stipe.
Spores 5-6.5 x 4-5.5 µm, smooth, elliptical; spore print chocolate brown.
Scattered to gregarious in disturbed habitats,
roadsides, paths, vacant lots etc., preferring heavy soils like those surrounding San Francisco Bay; fruiting from mid to late winter.
Excellent; substantial size, firm texture, and good flavor make this one of the best
species for the table.
is recognized by a usually short, compact, stature, smooth, white, but frequently dirty cap, and partially emergent fruitings, i.e. often just breaking through the soil surface. It is most likely to be confused with
, which is also white and similar in stature, but the latter has a distinct briny odor and the flesh turns pink when cut.
Bougher, N.L. & Syme, K.
(1998). Fungi of Southern Australia. University of Western Australia Press: Nedlands, Australia. 391 p.
Desjardin, D.E., Wood, M.G. & Stevens, F.A.
(2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
(1986). The Agaricales (Gilled Fungi) of California. 6. Agaricaceae. Mad River Press: Eureka, CA. 62 p.
of North America. New York Botanical Garden: Bronx, NY. 574 p.
(2008). Agaricus L.; Allopsalliota Nauta & Bas; Tribu Agariceae S. Imai: Part 1. Edizioni Candusso: Alassio, Italy. 824 p.
(1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
Other Descriptions and Photos
(D & CP)
Arora (1986): p. 321 (D & P), plate 80 (CP)
Arora (1991): p. 121 (D & CP)
Jordan: p. 222 (D & CP)
Kerrigan: p. 23 (D & CP)
Lincoff: p. 503 (D), plate 157 (CP)
Miller: sp. 215 (D) [as
Phillips: p. 190 (CP), p. 191 (D)
Smith & Weber: sp. 169 (D & CP)
(D=Description; I=Illustration; P=Photo; CP=Color Photo)
The Fungi of California
Copyright © 1996-2016 Michael Wood & Fred Stevens