yeah, sumac is a soft wood, worthless as a fire wood. I'll tell you though, that and Ailanthis, are two trees, native or not, that animals and songbirds find very beneficial. They love em. I've seen deer literally MOW the leaves off of doned trees that I've cut in the summertime, and yes, the rabbits LOVE the bark. I have no qualms cutting either. They are the most prevalent trees on my farm, and if you stump cut without treating with spray, you'll have multiple shoots that grow to 10' in one year.