Epithet = loving ash (Fraxineus). Genus = perennial pored.
Perennial, single or overlapping conks formed on trunk and main branches. Upper side narrow to wide, with a rounded whitish margin, older parts gray to black and cracked. Pores whitish, 3–5 per mm. Flesh pale brown to moderate brown. Spores are white, 9–11 μm, elliptical, thick-walled, truncate at end with germ pore.
Truncospora ohiensis (Perenniporia) is small and has larger spores. Other bracket-shaped Perenniporia are differently colored.
Ganoderma has smaller pores and the pore surface bruises brown; has brown spores.
Phellinus has brown pore surface and darker brown context, turns blackish with KOH; has brown spores.
Fomes fomentarius is more hoof-shaped and has brown pore surface; typically on birch or beech.
Fomitopsis pinicola, typically on conifers, has an orange or reddish zone on top; causes a brown rot.
Pathogen of ash, some reports on other hardwoods, also juniper (in Arizona). White mottled rot, mainly heartwood(?)
Perennial brackets can be found year round.
Known only from North America (Gilbertson and Ryvarden 1987).
Widespread across the range of ash in the U.S.A. and adjacent Canada; rare on the West Coast, absent from Gulf Coast.
Chicago Region status
Rare, even though ash trees are common.
Only recently collected from 2011, 2012, 2013, 2015, on ash trees on north-west side of Chicago. Also found in 2015 on live ash in Kane County and dead ash in DuPage County.
E.T. Harper, River Forest 1897 [UC];
V.O. Graham, Glenview 1940 [BPI, NY, UC];
C. B. Stifler, Evanston (approx. 1930's) [BPI]; and
J.C. Carter, Hinsdale, DuPage County 1944 [ILLS].
Reported for River Forest and Glen Ellyn in Moffatt (1909).
P.R. Leacock 8626, 10335, 10842, 12367, 12505; C. L. McAllister 110.
Taxon Details and Links
Norwegian Journal of Botany 19: 143 (1972)
C.H. Peck, New Species of Fungi. Botanical Gazette Crawfordsville 7 (4): 43-44 (1882)
Polyporus fraxinophilus.— Pileus sessile, thick, corky, more
or less ungulate to somewhat decurrent, concentrically sulcate,
rimose when old, the first year whitish, then gray or cinereous, finally
black, the margin obtuse, the substance obscurely zoned within, at
first whitish, then isabelline; pores medium size, stratose, nearly
plane, subrotund, the dissepiments obtuse, entire, whitish; spores
white, broadly elliptical, .0003-00035 of an inch long, .00025-0003
Pileus 2-4 inches long, 1-2 inches broad.
Dead or languishing trunks of ash trees. Dakota. C. W. Irish.
Arizona. C. G. Pringle.
This Polyporus belongs to the Fomentarii. It varies considerably
in shape, some specimens being almost as much flattened as
the thicker forms of P. applanatus, others being as thick as the
ordinary forms of P. fomentarius. Specimens three or more years
old are somewhat tri-colored, the oldest part being black and full
of chinks or cracks, the margin whitish and the intermediate part
gray or cinereous. The annual additions are separated by concentric
grooves. In the Dakota specimen the annual additions are
much broader than in the Arizona specimens, and the pileus is
more flattened and thinner. The interior substance is at first
whitish but it changes with age to a brownish-yellow or isabelline
hue, thus forming a connecting link between the second and third
sections of this tribe as given in the Epicrisis of Fries.
This species has also been transferred to Scindalma (1898) and Poria (1964).