Summary: Features include tough perennial or persistent fruitbodies growing flat on hardwood with the pore surface exposed, the color varying from grayish to bright yellow, and microscopic characters including thick-walled dextrinoid spores and dextrinoid skeletal and binding hyphae.
Odor: insignificant (Breitenbach)
Taste: bitter (Breitenbach)
Microscopic: spores 5-6.5 x 3-4 microns, broadly elliptic to oval, usually truncate, smooth, weakly to strongly dextrinoid, colorless, thick-walled; basidia 4-spored, 19-27 x 7-11 microns, broadly clavate with narrow base, with basal clamp; cystidia none, cystidioles not projecting 15-22 x 7-8 microns, fusoid, with basal clamp, hyphal pegs present; hyphal system trimitic: subiculum generative hyphae 2-4 microns wide, thin-walled, with clamp connections, subiculum skeletal hyphae 2.5-5 microns wide, thick-walled, nonseptate, binding hyphae 1.5-2 microns wide, thick-walled, nonseptate, much-branched, skeletal and binding hyphae dextrinoid, trama hyphae similar, (Gilbertson), spores 5-6.5 x 3.5-5 microns, broadly oval, truncate, smooth, inamyloid, pale yellow, thick-walled, (Breitenbach)
Spore Deposit: pale yellow (Buczacki)
Notes: Perenniporia medulla-panis has been found in BC, WA, OR, ID, AL, AR, AZ, CA, CO, DE, GA, KY, LA, MD, MI, MO, MT, NC, NM, NY, PA, SC, VA, and WV, (Gilbertson). In BC, it is known from three collections (Ginns).
Habitat and Range
SIMILAR SPECIES
Perenniporia subacida grows on Picea (spruce) and differs by dextrinoid and barely branched skeletal hyphae, (Breitenbach, but Gilbertson(1) give P. medulla-pannis as having variably dextrinoid skeletal hyphae and truncate spores while P. subacida has strongly dextrinoid wider skeletal hyphae and oval spores).
Habitat
annual to perennial, on dead wood of numerous hardwood genera, rarely on conifers, causes white rot of dead hardwoods, (Gilbertson), on dead wood of Quercus (oak), according to literature also on Robinia (locust) and Picea (spruce), (Breitenbach), all year (Buczacki)