Maybe its a personal bias, as elm was my first. But, I have never made a bow so short, with such a draw length and draw weight as my first elm bow. 47 inches ntn, 50@24, stiff handle, and made of a 1.5 inch sapling. I hunted an entire season with this bow. It did develop a crack in the back because I left the bark on. The cambium lifted and took some sapwood with it. I have a rawhide patch from a doe over it and it still can be shot, but I dont wanna risk it. With what I know now, I wish I could have this stave back and do it over. Anyways, elm has an interlocking grain that rivals hickory ( generally ) and as a result, can really take tension loads no other wood can. It likes a high crown and a flat belly. I would challenege anybody to make a bow like this from any other wood. I bet they wont, even with osage. Elm is KING.
By the way, keep your sap wood on that stave. Its a great back.