Willow Bracket - Phellinus igniarius

A large thick bracket usually found on willow trees, sometimes hoof-shaped.  Upper surface is hard and woody, with concentric ridges, and is grey or black, with a paler reddish margin.  Older specimens are cracked and blackened as though they have been in a fire.  The under surface has fine pores and is reddish or grey.  

Other polypores and brackets. The hoof fungus Fomes fomentarius can look similar, but is usually on Birch trees.

You must note the species of tree on which you have found it, and photograph the upper and under surfaces.

Usually willow trees