prl12566a prl12566b

Meripilus sumstinei (Murrill) M.J. Larsen & Lombard

Mycologia 80: 615 (1988)

black-staining polypore. Species named in honor of collector David Ross Sumstine (1870 - 1965).
Large compound fruitbody formed of overlapping caps. Caps 5–20 cm wide, whitish to yellowish brown, may be radially streaked or zoned. Pore surface whitish to light brown or darkening; pores small, 3–5 per mm (apparently 6–8 per mm when dried). Upper and lower sides bruising black after handling or with age. The short basal stem may become black and tuberous. Texture is very fibrous; easily splitting radially. Odor mild. Spore print white. Hyphal system monomitic; clamp connections absent.
Similar species:
None of the similar species bruise black. Grifola frondosa has smaller lobed fronds, grayish to brownish and white pores; pores are 2–4 per mm. Laetiporus species have brighter coloration. Bondarzewia is cream-colored and thick-fleshed with larger pores (1–2 per mm), caps not streaked; spores with amyloid ornamentation.
Saprobe and probably parasitic, on hardwoods at bases of trees, roots, and stumps, causing a white rot. Often with oak, also recorded for beech and hickory. Some reports in the west are with conifers, such as Douglas-fir.
Summer and fall; July to mid October in Chicago Region.
Widely distributed in eastern North America, less common in the west.
Chicago Region status:
Uncommon. Recorded in widely scattered locations of six counties across the region. Surprisingly not documented for the much-studied Cook County until twice in 2015.
LECTOTYPE - United States, Pennsylvania, [on Quercus sp. - MJL], date of collection unknown, D. R. Sumstine No. 11 (NY).
Index Fungorum (August 2015) shows the synonymy as listed above. Mycobank (August 2015) has this species as a synonym under Meripilus giganteus.
Specimens examined:
Six collections from five counties.
Description links:
Michael Kuo ; Gary Emberger ; Missouri Department of Conservation.
Related links:
Larsen, M., F. F. Lombard. 1988. The status of Meripilus giganteus (Aphyllophorales, Polyporaceae) in North America. Mycologia 80(5):612–21. PDF from Forest Service.
Records online:
Mushroom Observer ; MycoPortal for Meripilus spp.
Taxon links:
135100 MycoBank ; Index Fungorum ; Species Fungorum