Today, I had a circle of bark skinned off my tree about 8 to 10 inches in length and 6 inches across. The man put a roofing sealer over the area. No damage was done to wood underneath, just bark damage, and is less than 25% of tree but after reading your tip about letting air heal it, have I let these people do something to kill my tree? Or is there something I can do to reverse what they did if I need to?
I would just wait and see. Trying to remove the roofing sealer may cause even more stress.