Lightest part of the image naturally draws the eye in, so the focal point is the white tree, not the dead one. I never even noticed it,till you mentioned it.
Try toning down the white one with curves or levels mask, and brightening the snag a bit.
Also, Id crop out the bottom i stead of the top.
Comverting to B/W is a good idea. Do you have Nik plugins? silver EFEX will give you options that should bring out the snag while pushing the white one into the background.
Maybe Orton-ize or gaussien blur elements you dont want the eye to focus on.
Is this an image you can reshoot from a different angle?