Common Names: Birch polypore, birch bracket, razor strop
The brackets burst out from the bark of the tree, and these fruiting bodies can last for more than a year. The fruiting bodies are pale, with a smooth greyish-brown top surface, with the underside a creamy white and with hundreds of pores that contain the spores. The fruiting body has a rubbery texture, becoming corky with age. Wood decayed by the fungus, and cultures of its mycelium, often smell distinctly of green apples.
Found almost exclusively on on birch trees. It is a necrotrophic parasite on weakened birches, and will cause brown rot and eventually death, being one of the most common fungi visible on dead birches.