Insect community composition on Sassafras in natural areas in southern Appalachia

In July 2019 laurel wilt, a fungal disease caused by an invasive pathogen, Raffaelea lauricola, was found on sassafras in north-central Tennessee. This disease is known to be transmitted by the redbay ambrosia beetle and has devastated redbay populations in the southeastern U.S. Nearly all plants in the family Lauraceae are known to be susceptible to laurel wilt. Sassafras is a member of the Lauraceae family endemic to the eastern U.S. Sassafras has a deep cultural significance and rich history of use in traditional practices by Native Americans and residents of the Appalachian region. Sassafras is also important from an ecological standpoint. Some species, such as caterpillars of spicebush swallowtails, are known to feed almost solely on a few laurel species, such as sassafras. Other arthropods may also exhibit a specialized dependence on sassafras. However, the insect community composition on sassafras has not been well studied. Because no treatment to cure laurel wilt or protect plants from infection is currently available, it has the potential to spread through most of the native range of sassafras. If sassafras becomes locally or regionally extinct due to the spread of laurel wilt, it is critical to have a basic knowledge of associated insect species to gauge insect species that may become rare, threatened, or endangered, or even locally or regionally extinct. Therefore, a study designed to determine insect community composition on sassafras was initiated at healthy and laurel wilt-infected sites in Tennessee. This research will inform protection of sassafras in natural areas.