| Macroscopic characters | shape | Dimidiate to semicircular or broadly attached |
| size | 1-5 x 2-8 x 0.3-2.0 cm |
| texture | Corky; coriaceous |
| pileus | Smooth; becoming cracked in older specimens; slightly zonate; hard crust; brownish gray to blackish gray; often greenish tint in age; tomentose to hispid |
| stipe | N/A |
| context | Brown; up to 6 cm thick; fibrous |
| pore surface | Brown; convex |
| pores | Lamellae-like; dichotomously forked |
| tube layer(s) | Up to 12 mm deep at the base |
| Microscopic characters | hyphal system | Trimitic |
| clamp connections | Present on generative hyphae; sparse |
| sterile elements | N/A |
| basidiospores | Cylindric; slightly bent; hyaline; 5-6 x 2-3 um |
| Habitat characters | substrate/host | Hardwoods; preferably on Betula spp.; occasionally on conifers |
| seasonality | Annual |
| type of decay | White rot of dead hardwoods |
| range | Common throughout the eastern and Midwestern hardwood forests of North America; extremely rare in the central Rocky Mountains |
| Notes | Easy to recognize due to hirsute to tomentose zoned pileus and the lamellate hymenophore |
| References | Overholts, 1953 Gilbertson & Ryvarden, 1986. |
