Elm sapwood is as tough as the rest of the wood in tension, but it isn't as HARD as the heartwood in compression. I never chase a ring on it, let the belly fall where it lies, and heat treat it.
On small diameter red elms, I often even find the very middle to be very vascular, almost punky, so lay out bows to be thin enoughn to avoid it.
I would be interested to know what specie you have there. It's quite pretty, but less dark in the heartwood than I am used to on a slippery elm, and the sapwood seems very thick to me for the red elms I am used to, which tend to have thin rings, and only a few of them, before I hit heartwood.