I have a lovely tall sugar maple and las yar I noticed some of the limbs higher on the tree were dying. Ths year about half of the tree is dead in dffeent parts and the bark is turning black and also the are holes in a circle about every 5-8 inches apart from bottom to top. I would like so much to know I could prune the tree and save it, but I have been told some kind of beetle or bug did the boring and it could not be saved. Please advise.