Sooty, since this is the 3rd J. maple to fail in one specific site, I think I'll just ditch it (it was a free tree) and not bother trying to pinpoint exactly what the issue is/was. As I recall, it was a bit of a spotty response - one limb would be infested, another was fine, which is in line with your thoughts. Thanks for replacement suggestions. I'm also thinking perhaps a sumac for the fall color and interesting form.
