Found along the Old Mount Si trail on our way back down from the summit. This is about a foot across (30cm) and they can be much larger. They are edible though I have never tried them. I believe this is the Yellow Coral, Ramaria rascilaspora. The photo is my wife's who got pictures of it than I did.

ronaldhanko-orchidhunter.blogspot.com/2013/05/mount-si.html