How to identify it?
Fruiting Body
Fruiting body rather large; one or several loosely arranged large lobes.
Cap
Cap 5-30 cm across, cylindrical to roughly elliptical; grey to beige, and even orange; surface dry, roughened, velvety. Flesh soft to stringy and leathery, brown to reddish brown. Taste bitter.
Pores
Pores decurrent, orange to bright yellow, becoming greenish yellow to olive or brown, 1–3 pores per mm. Stem 2-5 cm long, short, off-center.

Scientific Classification

Phylum
Club fungi Class
Mushroom-forming fungi Order
Shelf fungi Family
Bracket polypores Genus
Phaeolus Species
Dyer's polypore