I have witness the multilation of the Northern Red Oaks on Cornell campus and many other places. I suspect that this is the result of brainless pursuit of the symptoms arises from the intentional neglect of the only proven recourse:
I was observing the tent caterpillars on trees at SUNY at Binghamton this spring, and I advised them to put the burlap barriers on the trees to kill the caterpillars as was being done at the Binghamton Courthouse at the time. They failed to follow my advice; thus the caterpillars severely decimated a lot of trees. As a result of this I have concluded that this is probably what the whole dieback scenario is all about. Dieback is merely a defense mechanism of the tree. Once a good percentage of the leaves are eaten, the tree will selectively die back in order to survive. All of the listed causes of dieback are probably merely symptoms. Ask and I will tell you great and hidden things you do not know. Yours truly, Bobby Meade