Postia leucospongia (Cooke & Harkn.) Julich
marshmallow polypore
Uncertain
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
marshmallow polypore
Uncertain
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
Photograph
Species Information
Summary:
Postia leucospongia forms a whitish shelf or bracket with whitish pores growing on the underside of a tough white layer that is covered on the upper side with soft spongy cottony material that usually extends over the margin below the pore surface and often partly covers it. Fruitbodies develop under snowbanks in the spring on dead wood in the mountains. The online Species Fungorum, accessed April 20, 2020, gave the current name as Tyromyces leucospongia (Cooke & Harkn.) Bondartsev & Singer, and Mycobank, accessed the same day gave the current name as Spongiporus leucospongia. The description is derived from Gilbertson(1).
Odor:
not distinctive (Bessette)
Taste:
mild (Gilbertson)
Microscopic:
spores 4.5-6 x 1-1.5 microns, allantoid [curved sausage-shaped], smooth, inamyloid, colorless; basidia 4-spored, 16-23 x 4-5 microns, clavate, with basal clamp connection; cystidia absent, hyphal pegs present; hyphae monomitic, hyphae of context 3-7 microns wide, "with abundant clamps, rarely with double clamps, thin- to thick-walled, with frequent branching", "some contorted, with short, nodular branches or swellings and appearing twisted", hyphae of trama similar to non-contorted type, (Gilbertson), spores 4-6 x 1-1.5 microns, more or less sausage-shaped, smooth, (Arora)
Spore Deposit:
white (Arora)
Notes:
Postia leucospongia has been found in BC, WA, OR, ID, AB, YT, AK, AZ, CA, CO, MT, NM, NV, UT, and WY, (Gilbertson). It is also known from the Himalayas.
EDIBILITY
no (Arora)
Habitat and Range
SIMILAR SPECIES
Compare also with Postia ptychogaster.Habitat
annual, on dead conifer wood "that is under deep snow for several months, particularly fir and spruce, rarely on aspen", developing under snow and deteriorating rapidly with onset of snow melt and higher temperatures, found throughout the western mountains, associated with brown cubical rot, (Gilbertson), single to gregarious on dead conifers, usually from fissures in bark, usually in the spring, often beginning development under the snow, but the fruiting bodies persist for months without decaying; causes a brown rot of both heartwood and sapwood, (Arora), on old logs and stumps of conifers at over 5000 feet altitude, found up to timberline, (Lincoff), single to several on decorticated [debarked] conifer logs, stumps, and limbs; Picea engelmannii (Engelmann Spruce) and Abies lasiocarpa (Subalpine Fir) are common hosts, but on other conifers as well; "fruiting on wood covered with snow, reaching maturity shortly after the snow recedes; from May to July", (Bessette)
Synonyms
Synonyms and Alternate Names:
Meruliopsis corium (Pers.: Fr.) Ginns
Thelephora corium Pers.