Oyster up a tree

There are suddenly lots of fungi at the nature reserve and I was spoilt for choice after a short walk there. In the end, I decided I liked this one best - I think it is a Veiled Oyster, Pleurotus dryinus, though it was too far up the ash tree to be able to see the top of the cap. If I'm right then true to the book descriptions, it was growing out of a long vertical wound scar.