[1] I. andersonii induces canker rot in oak, hickory, cottonwood, and willow trees.

[2][3] Wood that has been infected by this species appears bleached of color and crumbles easily.

The bark near expanding or developing cankers may also ooze varying amounts of dark sap.

The fruiting bodies (basidiocarps) of this fungus may appear on living trees or on recently failed stems.

[3] I. andersonii is "a true pathogen of living trees with a pronounced specificity for oak, [that] exhibits annual, widely effused fruitbodies, monomitic hyphal system, and broadly ellipsoid, yellowish, thick-walled basidiospores.