Hygrophorus subalpinus
Univ. Mich. Herb. Contr. 5: 19. 1941.
Common Name: none
Cap 60-120 (150) mm broad, suberumpent to erumpent, convex, expanding to plano-convex, disc sometimes depressed; margin incurved, becoming decurved, occasionally wavy with veil fragments; surface white, subviscid to dry, when moist, often with adhering debris; context white, firm, unchanging, up to 2.0 cm thick, odor and taste mild.
Gills adnexed, subdecurrent to decurrent in age, close, white, maturing cream, edges even, 4-8 mm broad; lamellulae in one to two series.
Stipe 40-100 x 30-50 mm broad, robust, solid, cylindrical, often with a bulbous base; surface dry, glabrous, white, firm, unchanging when cut; partial veil, fibrillose-membranous, evanescent, leaving a thin volva-like remnant at the base or fragments on the young cap margin.
Spores 7.5-10.5 x 4.5-5.5 µm, elliptical in face view, slightly inequilateral in profile, hyaline, inamyloid, hilar appendage inconspicuous; spores white in deposit.
Solitary to gregarious, partially emergent in duff of montane conifers, both Sierra Nevada and Coast Ranges; fruiting from spring to mid-summer at higher elevations, occasional in the fall; common in most years.
Edible and good with meaty texture and good flavor.
Hygrophorus subalpinus is a robust montane species recognized by stocky stature, a white, glabrous cap, waxy often decurrent gills, and an evanescent partial veil that typically leaves a thin volva-like remnant on the lower stipe. Like a number of montane species, the fruiting bodies of Hygrophorus subalpinus develop partially under the duff, protected from the often dry mountain air. Investigating mounds of fresh litter is the key to finding this and ecologically similar species. Hygrophorus subalpinus should be compared with unrelated white mushrooms such as Amanita ocreata, Tricholoma murrillianum (Matsutake), Trichololma vernaticum, and Russula brevipes. Amanita ocreata is a toxic spring fruiting species that is similar with a cream colored cap, but has a more upright stature, lacks decurrent gills and occurs under oaks at lower elevations. Tricholoma murrillianum is a robust white species that closely resembles Hygrophorus subalpinus with a sheathing basal veil, and sometimes fruits under montane pines. It is easily distinguished, however, by a spicy odor, rusty brown stains that develop on the fruiting body, and a fall fruiting habit. Another Tricholoma, T. vernaticum fruits in the spring under montane conifers, but the cap is greyish, the gills are not decurrent, and it has a strong raw potato or cucumber odor. Russula brevipes is also similar in stature to Hygrophorus subalpinus, but rarely fruits in the spring and differs with brittle stipe, gill, and cap tissues.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Hesler, L.R. & Smith, A.H. (1963). North American Species of Hygrophorus. University of Tennessee Press: Knoxville, TN. 416 p. (PDF)
Largent, D.L. (1985). The Agaricales (Gilled Fungi) of California. 5. Hygrophoraceae. Mad River Press: Eureka, CA. 208 p.
