Burned Area Recovery from the Chimney Tops 2 Fire, Great Smoky Mountains National Park

Left: To monitor hemlock woolly adelgid infestation, staff collected infested hemlock branches during the larval stage of the beetle.

Right: The larvae of the hemlock woolly adelgid are collected and tallied as they drop to pupate.

NPS

In November 2016, the Chimney Tops 2 Fire burned in Great Smoky Mountains National Park, growing to over 10,900 by acres by the time it was contained. Post-fire, the park has undertaken several projects to stabilize and restore the landscape, including a project for the cultivation and preservation of eastern hemlock.

Eastern hemlock is in decline due to invasions of the exotic hemlock woolly adelgid. The trees are further threatened by fire because of its thin bark. If extreme drought and high winds push fire into hemlock forests there is potential for large scale tree mortality and loss of this iconic tree. After the Chimney Tops 2 Fire, the park decided that the best approach to keeping these trees on the landscape was to treat the hemlock woolly adelgid with a stop gap chemical control, release biological control agents to reduce adelgid numbers and to monitor efficacy.

AmeriCorps team members apply an injectable form of imidacloprid that will control hemlock woolly adelgid for up to seven years.

NPS

Trees within the fire perimeter have been treated with systemic insecticides and biological controls such as the introduction of a predatory beetle Laricobius osakensis. The beetle is documented as a known adelgid predator and post fire monitoring showed that in the low fire severity sites, beetles were able to survive and are now continuing to reproduce. Augmentations of more predators are continuing in the area to reach a long-term predator prey balance needed.

Monitoring in 2019 and 2020 indicated that trees in the low to moderate fire severity sites, with some charring, continue to recover from fire effects. This trend should continue with healthy canopy trees seeding the understory in the burned area.