Geograph - photograph every grid square

The other side of the trunk shows a long vertical wound, as though the young tree had been split in two and had grown back together, becoming infected during the slow process. Fellow-contributor Mike Richardson quickly emailed me to say "I'm pretty certain this is Inonotus hispidus. It occurs most frequently on Ash, and has a felty brown upper surface [hispid], not hard like a lot of brackets."
Someone has poked a short stick into the fruiting body.