Summary:
Lentinellus vulpinus is recognized by 1) shelf-like or shingle-like clusters with a fused base, 2) a white to yellowish tan cap with a woolly surface, 3) crowded, toothed gills, 4) a distinct short, stout stem, 5) a peppery taste, 6) growth on logs or trunks of hardwoods, 7) a white spore deposit, and 8) nearly round, amyloid, weakly spiny spores.

Cap:
5-10cm, "sometimes even larger, shell-shaped", convex then flat-convex, "pubescent from cottony or even woolly layer, pale clay pink or vinaceous buff below which becomes prominent with age, sometimes woolliness forming raised irregular scales especially at margin which is inrolled and obscurely ridged at first", (Watling), cap 5-10(25)cm broad, a shelving or shingled cluster of convex fruitbodies, conchate [shell-shaped], margin inrolled at first; white, "pale pinkish buff", to "pale pinkish cinnamon"; covered by pubescent cotton to woolly layer, margin "obscurely ridged at first, some ridges becoming raised and prominent in many specimens in age, occasionally raised or recurved squamules develop near the margin as well", (Miller), 5-10cm, shaped like shell; white to yellowish; evenly covered by downy cotton to woolly layer of short hairs, (Mochizuki), 5-11.5cm, convex, shell-shaped, "velvety to fuzzy, covered with short white hairs over a pale pinkish to pale cinnamon ground color, dry or moist", (Bessette), 2-8cm wide, up to 5.5cm deep, broadly ligulate to pleurotoid, more or less conchate to depressed, "margin downturned, loosely to tightly inrolled", thin, "radially undulate to delicately rivulose"; "off-white all over, off-white inward to pallid tan outward (fresh)", or rufous tan all over (dried); "superficially smooth to thickly tomentose over attachment", velvety to suede-like outward, "minutely hoary with common erect, minute hyphal fascicles", margin naked (smooth, dark brown) to delicately pruinose (and then colored as cap), "lined as though striate but not so, developing a white, superficial tomentum", (Petersen)

Flesh:
watery, pliant, soft; "ivory to vinaceous pink to pale buff close to gills", (Watling), watery pliant to soft at center; dingy white with pinkish or light brownish tint, "pale pinkish cinnamon" to light "sayal brown", darkening near gills, (Miller), watery; dull white with pinkish to brownish tints, (Bessette), 0.1-0.6cm thick, corky; off-white when fresh, drying pallid buff, when dried sometimes showing a black line (representing pileipellis between flesh and suprapellis), (Petersen)

Gills:
"replaced by close or crowded, broad, equal, shortly decurrent ridges with lines running down stem"; pale pinkish cinnamon, but becoming brown on handling or when old, (Watling), short decurrent with thin ridges extending down stem, often breaking transversely, close to crowded, broad, equal; whitish becoming "pale pinkish cinnamon"; edges roughly serrate, (Miller), decurrent with thin ridges extending down stem; whitish becoming pale pinkish cinnamon; roughly toothed, (Mochizuki), short decurrent with ridges extending down the stem, close to crowded; whitish becoming pale pinkish cinnamon; edges serrate, (Bessette), "deeply decurrent, close to crowded", up to 0.35cm broad; probably ocher to ochraceous tan when fresh, deep ocher to ochraceous brown and fragile when dried; becoming overgrown with white tomentum on stem; edge "shallowly serrate to entire over significant lengths", (Petersen)

Stem:
strongly eccentric, "short, stout, fused to form a common base"; light fawn; "dry, pubescent and ridged from decurrent gills", (Watling), short, stout, fused to form large common base, solid; light brown; "dry, pubescent and ridged by the decurrent gill edges", (Miller), "short, stout, fused to form a large common base, dry covering of short, soft, downy hairs ridged by the decurrent gill edges"; light brown, (Mochizuki), lateral, short, usually less than 5cm long, "stout, narrowed downward and fused with others to form a common base"; pinkish brown; dry, velvety to fuzzy, (Bessette), 0.8-1.5cm x 1.5-2.2cm, ridged in upper part from decurrent gills, "irregularly lumpy downward, covered with white tomentum", (Petersen)

Odor:
not distinctive (Watling, Miller, Bessette), strong of licorice (Petersen)

Taste:
peppery (Watling, Miller, Bessette), slowly peppery, reportedly bitter, (Petersen)

Microscopic spores:
spores 3.5-4.5 x 2.5-3.5 microns, nearly round, echinulate [spiny], amyloid; basidia 4-spored, 17.5-25 x 4-6 microns, colorless in water; pleurocystidia and cheilocystidia "usually lacking or if present then infrequent, narrowly clavate and thin-walled"; clamp connections present, (Watling), 3.5-4.5 x 2.5-3.5 microns, nearly round, minutely echinulate [finely spiny], amyloid, nearly colorless in KOH; basidia 4-spored, 17-25 x 4.2-6.0 microns, colorless but light yellow in mass in KOH; cystidia usually absent, if present, infrequent, narrowly clavate, and thin-walled; cap cuticle at tangled mass of thin-walled or slightly thick-walled hyphae 2.5-5.0 microns wide, yellowish in Melzer''s reagent to light yellowish in KOH, with scattered clamp connections, subcutis a narrow compact band or darkly amyloid intermixed with inamyloid hyphae 2.5-4.5 microns wide, thick-walled (1-2 microns thick) dingy yellow in KOH, composed of radiating parallel hyphae as viewed in tangential section; cap trama of loosely interwoven hyphae 2.5-9.5 microns wide, dark amyloid with a reddish brown cast, thick-walled (0.9-2.5 microns thick) intermixed with colorless thin-walled cells in Melzer''s solution, light yellowish in KOH, (Miller), spores 3.5-5 x 2.5-3.5 microns, nearly round, weakly echinulate, amyloid, (Bessette), spores (3.0)3.8-5.0 x (2.5)3.0-4.1 microns, nearly round, flattened somewhat adaxially, ornamentation of scattered aculei hardly discernible at 1500X, thin-walled, amyloid; basidia 4-spored, 16-24 x 5.0-5.8 microns, emergent up to 8 microns, "clavate when young, subsphaeropedunculate to broadly cigar-shaped at maturity", colorless, with basal clamp connection; hymenium with two other elements: 1) gloeocystidia rare, 8-10.5 microns wide, "emergent up to 15 microns, arising from lateral stratum, hardly emergent to immersed" [using mu plus "m" for microns], contents coscinoidal [foamy], and 2) leptocystidia rare, 2-2.5 microns wide, filamentous, colorless, thin-walled, [illustrated as emergent for a small fraction of their length], (pleurocystidia doubtful as a third element); cap trama dimitic, tightly interwoven, with 1) generative hyphae perhaps adherent, (2.8)4.2-9.5(12.0) microns wide, colorless, thin-walled to thick-walled (wall up to 1.5 microns thick, occasionally to commonly occluding cell lumen), "frequently to infrequently clamped, moderately amyloid (from weakly to strongly, dictated by wall thickness, mauve to avellaneous singly to pallid mauve-purple or dull purple in mass)" and 2) occasional to rare gloeoplerous hyphae, 2-7.0 microns wide (usually at narrower width), hardly yellow-refringent in KOH; cap cuticle "a repent, radial, coherent layer of generative hyphae", hyphae 3.5-5.5 microns wide, colorless singly, weakly straw-colored in mass, "thin-walled, frequently clamped, ?involved in mucus", darkening when old to become a dark brown layer, (Petersen)

Spore deposit:
white (Watling)

Notes:
It is infrequently encountered in northern North America but has been found in ID, AK, MI, VT, and Sweden, (Miller(10)). Collections were examined from ID, MI, MN, PA, Finland, France, and Sweden, (Petersen(25)). It has been reported from BC (in Ginns(20) 1986). There are collections from BC at the Pacific Forestry Centre, and collections from WA, ON, and MI at the University of Washington.

EDIBILITY

inedible (Bessette)

Synonyms and Alternate Names:
Lentinus vulpinus Fr.