Gyromitra montana is a stocky spring false morel of western North American mountain conifer forests, often fruiting near melting snowbanks. It has a compact, wrinkled to convoluted yellowish- to reddish-brown cap on a very thick, whitish stem. It is the western North American species long reported as the European Gyromitra gigas, and it is very hard to separate from the eastern G. korfii without a microscope.
Not recommended; treat as poisonous. It is a false morel, the group in which gyromitrin (converted to monomethylhydrazine) causes severe and sometimes fatal poisoning. It is eaten in parts of the West and one tested specimen lacked gyromitrin, but poisonings have been reported and toxin levels can vary. Do not confuse with the deadly Gyromitra esculenta. True morels (Morchella) have regular pits and ridges and are hollow in one chamber. Details in notes.
Never eat a wild mushroom based on a web page — confirm with an expert.
Habitat
Solitary, scattered or in groups on soil, humus and sometimes rotting wood under conifers in mountains, often near melting snowbanks (one MushroomExpert collection was around dead standing Engelmann spruce at about 11,000 ft). Usually considered saprobic, possibly mycorrhizal. Spring, later at high elevations (into August).
Distribution
Western North America, from the Rocky Mountains westward (MushroomExpert); in California at higher elevations of the Sierra Nevada (Mykoweb); also collected in Oregon. The European Gyromitra gigas is not known to occur in North America; North American reports under that name refer to G. montana in the West or G. korfii in the Midwest and East.
Characteristics
Cap: 5-10 cm broad and 4-7 cm tall (Mykoweb); compact, convoluted and folded, rarely lobed; margin irregular, incurved and pressed against or fused to the stem; yellowish brown, becoming dull reddish brown in age; underside whitish. Stem: short and stout, 2-8 cm tall and 3-7 cm thick, whitish, grooved to folded, with longitudinal passages visible in cross-section. Flesh: thin (1-2 mm), brittle; odor and taste not distinctive. Spores: 25-35 x 12-16 µm, elliptical, smooth, some with thickened ends (apiculi), each with one large central oil droplet (Mykoweb); MushroomExpert gives 26-40 x 11.5-15 µm with short, blunt apiculi often present. Key features: brain-like brown cap on a stem nearly as wide as the cap; spring fruiting near snowmelt under conifers.
