It's gorgeous, whatever it is! Thanks for sharing!

Kate

That's something in the genus Laetiporus. Usually called "chicken of the woods". There are a few species in the genus that are pretty similar, and the taxonomy is currently in flux. As the name suggests, it is edible, though not one of the fungi people usually seek out.

Patrick Alexander

Just remarked about this on another post. This is an absolute sign that this tree has some serious root rot going on. A brown heart-rot may even be systemic throughout the entire tree. Fungal fruiting bodies, such as these, though incredibly beautiful, speak loudly to the pathology within the tree.

If this were my tree (it looks like it might be an oak?), I would have to make a serious evaluation of its health and safety.

Yeah looks like chickn to me. I had some this this year. Good stuff. I say eat it.