|California Fungi—Gyromitra esculenta
(Photo: © Fred Stevens)
(Persoon: Fries) Fries
Summa Veg. Scand. II: 346. 1849.
false morel, rain mushroom, beefsteak morel
Cap 5-9 cm tall, 5-11 cm broad, semi-globose, brain-like, inconspicuously lobed; fertile surface convoluted to wrinkled, lobes separated by deep furrows; color: tan-brown, ochraceous-brown, deep reddish-brown; sterile undersurface of cap cream to buff-colored; margin attached to stipe at several points; context thin, brittle; odor and taste not distinctive.
Stipe 3-6 cm long, 1-3 cm thick, hollow, round to compressed, sometimes grooved or with basal folds; surface smooth to furfuraceous, whitish, often tinged vinaceous-tan.
Spores 18-23 x 9-12 µm, ellipsoid, smooth, with two oil droplets; spores pale yellowish-buff in deposit.
Solitary, scattered to gregarious under conifers, occasionally under hardwoods; common in the Sierra, rare in coastal forests; fruiting from late winter to spring.
Potentially deadly, especially raw, but see comments.
Commonly known as the Brain Mushroom because of its much wrinkled, typically reddish-brown cap,
is one of the more distinctive members of the "False Morel" group. Nonetheless, it is sometimes confused with morels (
spp.) The latter are easily distinguished by their longitudinally ridged, pitted caps. Although the species name suggests edibility,
is a questionable choice for the table as it contains monomethylhydrazine (MMH), a volatile toxin which in high doses can be fatal. Anecdotal evidence and preliminary tests by Duffy and Vergeer suggest that California material may not contain high levels of MMH, but caution is still advised. Although we cannot recommend eating this mushroom, it is commonly consumned in the Western United states. If you do try
, it should always be cooked in a well ventilated area to avoid breathing any monomethylhydrazine that might be present and the cooking liquid should be discarded.
Other California Gyromitras include:
has a distinctive saddle-shaped cap, the surface of which is wavy to bumpy, but not wrinkled.
(Snow Mushroom), until recently known locally as
, is largely a Sierran species. It is shorter, stockier than
with a coarsely wrinkled cap only slightly broader than the stipe. Least likely to be encountered is another Sierran species,
. A beautiful fungus, it has a broad, brown to olive-brown, wavy cap, the margin of which is usually free, and a fluted, cream-yellow, often tinged pinkish stipe.
Abbott, S.O. & Currah, R.S.
(1997). The Helvellaceae: Systematic revision and occurrence in northern and northwestern North America. Mycotaxon 62: 1-125.
Ammirati, J.F., Traquair, J.A. & Horgen, P.A.
(1985). Poisonous Mushrooms of the Northern United States and Canada. University of Minnesota Press: Minneapolis, MN. 396 p.
(1986). Mushrooms Demystified. Ten Speed Press: Berkeley, CA. 959 p.
Breitenbach, J. & Kränzlin, F.
(1984). Fungi of Switzerland. Volume 1: Ascomycetes. Verlag Mykologia: Luzern, Switzerland. 310 p.
Castellano, M.A., Cázares, E., Fondrick, B. & Dreisbach, T.
(2003). Handbook to additional fungal species of special concern in the Northwest Forest Plan (Gen. Tech Rep. PNW-GTR-572). U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: Portland, OR. 144 p. (
Desjardin, D.E., Wood, M.G. & Stevens, F.A.
(2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
(2008). Toxic Fungi of Western North America.
Siegel, N. & Schwarz, C.
(2016). Mushrooms of the Redwood Coast. Ten Speed Press: Berkeley, CA. 601 p.
(1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.
(1979). Mushrooms of Idaho and the Pacific Northwest: Discomycetes. University of Idaho Press: Moscow, ID. 133 p.
(1988). A Morel Hunter's companion. Two Penninsula Press: Lansing, MI. 288 p.
Other Descriptions and Photos
Le Cercle des Mycologues de Montréal:
(D & CP)
Pilze, Pilze, Pilze:
Arora (1986): p. 801 (D), p. 802 (P), plate 206 (CP)
Arora (1991): p. 234 (D & CP)
Jordan: p. 51 (D & CP)
Lincoff: p. 336 (D), plate 714 (CP)
McKenny: p. 202 (D), p. 203 (CP)
Miller: sp. 395 (D & CP)
Orr & Orr: p. 34 (D), plate 6 (CP)
Phillips: p.302 (CP), p. 303 (D)
Smith (1975): sp. 15 (D & CP)
Smith & Weber: sp. 21 (D & CP)
Tylutki (1979): p. 70 (D & P)
Weber: p. 145 (D & CP)
(D=Description; I=Illustration; P=Photo; CP=Color Photo)
The Fungi of California
Copyright © 1999-2020 Michael Wood & Fred Stevens