Mushrooms appear at the base of the tree. Mushrooms, along with carpenter ants, termites and peeling bark, are symptoms, but not the cause, of decaying wood. A certified arborist should assess the decay. If the decay is severe, the tree should be removed. If not, keep watch on it and reassess every three to five years.
Branches break off because of poor branch structure and weak angles.
Or thin out branches to that distance. Wider angles make stronger branches. Lightning struck the tree and blew off bark. If more than one-third of the leaves die, remove the tree,'' says MacNair. Don't use tree paint and don't fertilize.