You could split it if you were careful. Just take some time to work out the best place to start it. If you put an axe in at various places along the line you want, on both sides of the log it will usually split down that line.
In an ideal world, you want the wood that was growing on the topside of the branch. That's the tension wood, and will have tighter grain and will (usually) make a better bow. The bottom side is compression wood, and will be more coarse. That said, quite often wood surprises you and you can get some superb bows from compression wood. Might not make a fantastic warbow however. You'll need to decide whether you work towards a heavy weight or not before you crack on with it.
You could use a former - I don't know how well that will work. You're probably better letting it season naturally, then straightening later. I've heard of a method (can't remember where) of taking a fresh, unseasoned stave and cutting the belly taper first before the width and letting it season like that. Apparently it will pull itself straight or into reflex as it dries. Could be complete garbage though, so possibly worth trying on something less valuable...!
