He managed Mt. Mitchell State Park, and he was right: The problem was caused by the Balsam Woolly adelgrid (link). What part of this statement do you not understand: "Balsam woolly adelgids have destroyed about 95% of the Fraser firs in the Great Smoky Mountains National Park, creating "ghost forests". " This is not from acid rain: Please Register or Log in to view the hidden image! It's caused by an insect (link).