Summary:
Fruitbodies in the Lyophyllum decastes group characteristically grow in large compact clusters in disturbed places. The caps are various colors of brown, often lobed, smooth and often lubricous. Gills are close and whitish. The often curved stem is also whitish, and may discolor brownish. The odor is mild. The group contains at least these species: 1) Lyophyllum decastes = Clitocybe multiceps = Tricholoma aggregatum, 2) Lyophyllum connatum (=Clitocybe connatum) with a white or whitish cap (=Clitocybe dilatata according to one source and easily confused with it according to another), 3) Lyophyllum loricatum with a blackish-brown to dark brown cap when young, often with a hoary sheen or a metallic luster, and with a thick cartilaginous cap cuticle: it fades with age to paler brown or tan and then indistinguishable from L. decastes, 4) a species with a grayish cap and grayish gills, and 5) another species that grows under mountain conifers soon after snow melt, (Arora). As a group, they are common along the west coast from Alaska to California.

Cap:
3-12cm across, "convex then expanded becoming wavy; gray-brown to yellowish brown with silky or silvery streaks; smooth, soapy", (Phillips), 6-10(15)cm across, hemispheric when young, later convex to flat and sometimes wavy, center usually with obtuse umbo, margin acute; "gray-brown to hazel brown, paler toward the margin, sometimes almost whitish"; smooth, lardaceous-shiny, cuticle peelable almost to center when moist, (Breitenbach), very variable in color "ranging from whitish to pale watery tan to grayish brown or almost black"; smooth, consistently slippery feel, (Trudell(4) who note that different color forms are sometimes considered separate species like L. loricatum and L. fumosum)

Flesh:
firm; white, (Phillips), thick in center, thin toward margin, elastic; white, (Breitenbach)

Gills:
"adnate to slightly decurrent or often notched, close"; white or pallid but sometimes becoming straw-colored when old

Stem:
3-10cm x 1-2.5cm, "solid, equal or tapering downward, often curved", white, sometimes discolored brownish when old, especially at base; smooth, dry

Microscopic spores:
spores 4-6 x 4-6 microns, round or nearly round, smooth inamyloid, basidia with siderophilic granules

Spore deposit:
white

Notes:
Lyophyllum decastes group has been recorded from AK, BC, WA, OR, and CA.

EDIBILITY

some mild cases of poisoning have been attributed (Arora)