Posted: 10/02/2013 at 09:58
Large sumac trees are very unstable, even those in good health. The roots are very shallow and they can easily topple over in high winds.
If you have a large tree that looks dangerous, then I'd cut the top off in a controlled manner.
If a large sumac tree is cut down then you will inevitably get a lot of suckers coming up over the entire area covered by its roots. You should be able to control these, and leave one or two to make new replacement trees.
Sumacs normally respond well to hard pruning. Prunning should create bigger leaves. You can keep a sumac tree trimmed to 6 feet or so, and that normally creates a nice full head of big leaves.