Summary:
Features include 1) resupinate growth on wood, 2) a tomentose, separable fruitbody that is gray to dull buff, the surface papillose to colliculose, the margin and subiculum almost white, 3) spores that are mostly round to nearly round, aculeolate to echinulate, and brown, 4) subicular hyphae that are colorless to pale brown (some with yellow-brown contents), with frequent clamp connections, and 5) white cordons.

Microscopic:
SPORES 5-6 microns in diameter, or 5-6 x 5 microns, mostly round to nearly round, sometimes irregular to irregularly round, "aculeolate to echinulate, walls hazel to dull brown"; BASIDIA 4-spored, 30-45 x 6.5-8 microns, clavate, sterigmata up to 5 microns long; SUBHYMENIAL HYPHAE 2.5-4 microns, colorless (parts sometimes green in KOH), thin-walled, with clamp connections; SUBICULAR HYPHAE 2.5-4(5) microns wide, walls colorless or light tan to pale brown (some with contents dull yellowish brown), thin-walled or with wall thickening slight, septate, with frequent clamp connections; CORDONS up to 90 microns wide, pale brown to almost colorless, individual hyphae 1.5-3 microns wide, thin-walled, with clamp connections, (Larsen)

Notes:
Tomentella cinerascens has been found in BC, WA, ON, AZ, MI, MT, NY, and SD, (Ginns), as well as Austria, Czechoslovakia, Denmark, Finland, France, Germany, Poland, Sweden, Algeria, and Turkey, (Larsen).

Synonyms and Alternate Names:
Auricularia pulverulenta Sowerby
Hypochnus cinerascens P. Karst.
Merulius pulverulentus (Sowerby) Fr.