E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Features include 1) a dark brownish gray cap with dark brown appressed or recurved scales on a grayish buff background, 2) buff to light gray gills that often become flushed orange-pink in areas, and 3) a stem with appressed or recurved scales, pale gray between the scales. T. atrosquamosum var. squarrulosum is regarded by many as a distinct species - see Tricholoma atrosquamosum for details. Heilmann-Clausen(1) note that the three photographs in Bessette(5) labeled as T. squarrulosum appear to be somewhat deviant from their concept of that species, based on the slender stem and occurrence under conifers, [the habitat disparity noted also by the authors of Bessette(5)].

Var. squarrulosum is widely distributed in North America, (Bessette(5) who show photographs from ID and CO from conifer forests). The photographs accompanying this program by M. Beug and Kit Scates-Barnhart were taken in conifer forests in Idaho. This is different from the hardwood habitat described by other authors, although the Latin description of Tricholoma squarrulosum Bres. in Saccardo''s Syll. fung. XVI: 21; XX: 1009 says "in pinetis campestribus". Ovrebo(2) examined collections of var. squarrulosum (as Tricholoma squarrulosum) from ON, MI, MN, and Austria. There are collections from BC at the University of British Columbia and a collection from WA at the University of Washington.

Gills:
"sinuate, close to crowded", subgills numerous; light gray fading to nearly white when old, "discoloring dark gray on the edges and often staining salmon-pink in some areas", (Bessette), white-gray, bruising slightly flesh-colored, (Moser), sinuate, 0.3-0.7cm broad, close, subgills "numerous but not arranged in distinct tiers"; light gray, fading to nearly white when old, "discoloring dark gray on edge" and often orange-pink in areas over several gills; edges entire, (Ovrebo)

Stem:
4-8cm x 0.5-1.5cm, "nearly equal with a rounded or slightly bulbous base, solid"; "with grayish to brownish appressed or recurved squamules, or with portions silky-fibrillose and pale gray", (Bessette), stem 4-5cm x 0.6-0.7cm, completely punctate-scaly, same color as cap, (Moser), 3.8-8cm x 0.5-1.5cm, "equal, the base rounded or subbulbous", stem solid; "with grayish to brownish appressed to recurved squamules, silky-fibrillose and pale gray between squamules", (Ovrebo)

Odor:
"variously described as farinaceous and somewhat disagreeable, sweet-fruity and somewhat spicy-peppery, or not distinctive" (Bessette), "farinaceous and somewhat disagreeable" (Ovrebo)

Taste:
"farinaceous to slightly bitter" (Bessette), farinaceous (Ovrebo)

Microscopic spores:
spores 5.7-7.2 x 3.8-4.8 microns, in side view "oblong or elliptic to narrowly elliptic, when elliptic often with adaxial face flattened", "narrowly elliptic in face view", smooth, inamyloid, colorless, thin-walled; basidia 4-spored, 23-29 x 5.7-6.7 microns, clavate, colorless; cheilocystidia "absent but occasional hyphal filaments projecting beyond hymenium"; clamp connections absent, (Ovrebo)

Spore deposit:
white (Ovrebo)