Name: Piptoporus betulinus
Author: (Bull.) P. Karst.
Citation: Revue mycol., Toulouse 3: 9 (1881)
Preferred Synonyms:Fomitopsis betulina (Bull.) B.K. Cui, M.L. Han & Y.C. Dai
Deprecated Synonyms: Agarico-pulpa pseudoagaricon Paulet, Boletus betulinus Bull., Boletus suberosus Batsch, Boletus suberosus Wulfen, Fomes betulinus (Bull.) Fr., Placodes betulinus (Bull.) Quél., Polyporus betulinus (Bull.) Fr., Ungularia betulina (Bull.) Lázaro Ibiza, Agaricum conchatum Paulet
Misspellings: Pitptoporus betulinus
Boletus betulinus Bull., Herbier de la France 7: t. 312 (1787) [MB#210846]
The fruiting body of Piptoporus betulinus has a pileus that is 1 1/8-10" (3-25.5 cm) wide with a shell, hoof, or kidney shape. The color is at first pale white, then acquiring a brownish tinge, and finally smoky grey with age. The surface of the cap often tears or breaks up into scales or patches as it ages. The most distinct feature of the fruiting body is the inrolled margin (most obvious at maturity), which remains as a rim around the pore surface.
The pore surface or hymenium is indented or depressed from the margin. When young the hymenium is cream colored and smooth, becoming pale brown to yellowish brown and jagged with age. The pores are circular to angular and there are 3-5/mm.
Although sometimes lacking, the stalk is lateral and up to 2 3/8" (6 cm), with a reddish-brown or brown color. The flesh is 3/8-2" (1-5 cm) thick, white, tough-fibrous, and corky.