Hello John:
Just thought that I would throw in a few comments about using white ash for timbers. I personally would have problem using the ash in lieu of red oak, around here ash was widely used for timberframing and is quite strong, but hard to work with, especially if it has become somewhat dry. I have reconstructed buildings using white ash and I had to hose the timbers down to keep them workable. I suspect red oak being a straighter grain would work easier, but it also will become very hard to work with if it dries out.
I don't know if this is of any use but that is my comment.