Monitoring the Impacts of Laurel Wilt Disease on a Rare Redbay Population at Cannon’s Point Preserve
Authors: Cameron C. Atkinson, Alisa J. Iketani, Kristin E. Ruff, and Kaitlin I. Spivey
Throughout the southeastern United States, laurel wilt disease is contributing to the decline of members of the plant family Lauraceae. In particular, redbay (Persa borbonia) populations have experienced widespread die-off due to laurel wilt. This disease is catalyzed by the invasive redbay ambrosia beetle (RAB; Xyleborus glabratus), which harbors a symbiotic fungus that proves deadly to redbay trees. When the RAB burrows into a host tree, it introduces the fungus into the xylem vascular tissue, triggering the tree’s defense system. Ultimately, the transport of water throughout the tree is blocked, leading to the systemic wilting of leaves and eventual death. As a component of our BIOL 4020 Conservation Biology service-learning project with the St. Simons Land Trust and Georgia Department of Natural Resources, we continued the annual monitoring of a rare redbay population at Cannon’s Point Preserve (CPP), St. Simons Island, GA. We evaluated 28 overstory redbay trees for signs of laurel wilt or RAB infestation. We also measured the diameter-at-breast-height of each tree and recorded reproductive activity when detected. Compared to previous years, only one new case of laurel wilt was documented, bringing the total count to 23% of monitored trees that have been infected since 2016. Continued monitoring, genetic resistance studies, and management of the invasive RAB are needed to protect this rare redbay population at CPP.