All water needs filtration, boiling, or other accepted treatment before drinking. Pests and disease also threaten the Smokies' ecosystem. Currently the most visible and serious threat is the balsam woolly adelgid. The small wax-covered insect attacks the Park's Fraser fir trees. The fir overreacts to the feeding adelgids, clogging its transport tissues.
Trees die within five years of infection.
Other pests and diseases affecting park ecosystems include chestnut blight, southern pine beetle, and dogwood anthracnose. The future promises additional problems. Gypsy moths, currently near the Virginia-Tennessee border threaten oak forests with total destruction. The hemlock woolly adelgid could eliminate Park hemlocks, and destroy the entire forest type. Both pests came from Europe.