A perennial resupinate polypore, sometimes with small false caps, rusty-brown in colour.  Pores are small, at 5 - 7 per mm.  The fertile surface has bristles (setae) but these are not present at the woolly margin - use low power microscope or high magnification hand lens in good light.

Rusty porecrust has setae at the margins

microscopy

Photograph fertile surface to show pores and woolly margin of a specimen to show absence of setae; note host plant and substrate.  If specimen is not examined closely and photographed, identification by an expert from examination of a specimen is needed before submission to NatureSpot. 

Deciduous wood, typically oak

Occasional in Leicestershire and Rutland.