Summary:
Clitocybe albirhiza is separated from its lookalikes by dense mycelium at base and growth in spring; other features include a light brownish cap that may have whitish down or river-like lines or concentric zones, adnate to decurrent gills colored like the cap or pale buff, stem colored as the cap, unpleasant or mild odor, bitter taste, and white spore deposit. Clitocybe albirhiza is common in the mountains of western North America.

Cap:
2-10cm across, convex becoming flat to broadly umbonate then depressed; watery brown to pale buff to cinnamon buff, pinkish buff or grayish buff; smooth or with whitish down, or with river-like lines, (Arora), 2.5-10cm across, convex at first, expanding to flat with disc sometimes slightly umbonate or shallowly depressed, gibbous [humped] at times, margin decurved [downcurved] to horizontal, finally infundibuliform [funnel-shaped], with margin elevated and often undulate [wavy] or incised; watery pale buff beneath areas of thin whitish canescence [hoar] when fresh, becoming watery brown ("cinnamon buff", "clay color") when old or when water soaked, fading or drying to pale buff or buff ("light buff", "pinkish buff", "warm buff"); more or less bald when old or when water soaked, opaque when faded or in dry weather, rivulose [with river-like lines] at times when old, (Bigelow), "pale buff to watery brown with faint concentric bands or patches of tawny pinkish buff", (Phillips)

Flesh:
thin; colored like cap, (Arora), moderately thick on disc, thin at margin, firm; colored as surface, (Bigelow)

Gills:
adnate to decurrent, close; pale buff or colored about as cap, (Arora), adnate to short-decurrent, close, narrow to rather broad (up to 0.9cm broad), at times forked, often interveined, faces veined at times; white at first, soon pale buff ("tilleul buff", "pale pinkish buff") or colored as cap, (Bigelow)

Stem:
3-8cm x 0.4-2cm, "equal or tapered at either end", often hollow when old, sometimes fluted; colored about as cap; base with dense mass of white mycelial threads, (Arora), 3-8cm x 0.5-2cm at top, equal or tapering either way, stuffed becoming hollow, flattened or fluted at times, usually central, fibrous, tough; colored as cap; bald or canescent when wet, fibrillose-striate in dry weather, base with dense mass of white rhizoids embedded in needles, (Bigelow), "smooth or downy when moist, becoming finely hairy and furrowed when dry", (Phillips)

Veil:
[presumably none]

Odor:
unpleasant or mild (Arora), slight, disagreeable, (Bigelow)

Taste:
disagreeable and bitter (Bigelow)

Microscopic spores:
spores 4.5-6 x 2.5-3.5 microns, elliptic, smooth, inamyloid, (Arora), spores 4.5-6 x 2.5-3.5 microns, elliptic, smooth, inamyloid; basidia usually 2- or 4-spored, occasionally 1-spored, 20-30 x 3.5-5 microns; [pleurocystidia and cheilocystidia presumably absent]; clamp connections present, (Bigelow)

Spore deposit:
white (Arora, Bigelow)

Notes:
Bigelow examined collections from ID, CA, and WY. It has been reported from WA by Andrew Parker, pers. comm. There are collections from BC at University of British Columbia.

EDIBILITY

unknown (Arora)