I personally like the elms here in Michigan. We have Gery Elm (American) and Red Elm (slippery elm) I've built a lot of bows from both. It is excellent bow wood in my opinion. My favorite bow woods from around here are......(no particular order).......slippery elm, grey elm, hard maple, ironwood. The elms seem to have more differences tree to tree than either maple or ironwood, but all make excellent bows.
rich