Tricholoma portentosum
Mém. Soc. Émul. Montbéliard, Sér. 2 5: 338. 1873.
Common Name: none
For description see Shanks, Bessette et al., Siegel & Schwarz, & 'California Mushrooms'.
Solitary to gregarious in duff under conifers (grand fir, western hemlock, pine); fruiting from late fall to mid-winter in coastal forests and in the Sierra foothills. Uncommon south of Humboldt County.
Edible and excellent.
Tricholoma portentosum can be distinguished by a dark grey to grey-brown, streaked viscid cap with conspicuous radiating fibrils, a faintly farinaceous odor and taste, growth with conifers, and a cap, gills, and stipe that develop yellow tones at maturity. If collecting for the table, it should be compared with the toxic Tricholoma pardinum, which has a dry cap with dark grayish brown to black squamules over a pale gray ground color, larger spores, conspicuous cheilocystidia, and clamp connections.
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Knudsen, H. & Vesterholt, J. ed. (2008). Funga Nordica: Agaricoid, boletoid and cyphelloid genera. Nordsvamp: Copenhagen, Denmark. 965 p. (PDF)
Knudsen, H. & Vesterholt, J. ed. (2012). Funga Nordica: Agaricoid, boletoid, clavarioid, cyphelloid and gastroid genera. Vol. 1. Nordsvamp: Copenhagen, Denmark. 511 p.
Shanks, K.M. (1994). A Sytematic Study of Tricholoma in California. Masters Thesis. San Franciso State University: San Francisco, CA. 207 p. (PDF)
Shanks, K.M. (1997). The Agaricales (Gilled Fungi) of California. 11. Tricholomataceae II. Tricholoma. Mad River Press: Eureka, CA. 54 p.
Siegel, N. & Schwarz, C. (2016). Mushrooms of the Redwood Coast. Ten Speed Press: Berkeley, CA. 601 p.
Trudell, S.A., Matheny, P.B., Parker, A.D., Gordon, M., Dougil, D.B. & Cline, E.T. (2022). Pacific Northwest Tricholomas: Are We Using the Right Names? Self Published: Seattle, WA. 103 p.
