| Abstract 2 An experimental study about an assessment of the rate of tree mortality by the redbay ambrosia beetle (Persea bornonia) has been observed in the coastal plain counties of Georgia and southeastern South Carolina since 2003 and northeastern Florida since 2005 (Fraedroch et. al 2008). The redbay mortality is due to a vascular wilt disease caused by Raffaelea sp. that is a fungal symbiont of Xyleborus glabratus, an exotic ambrosia beetle. The fungus is introduced into healthy redbay during beetle attacks on stems and branches. Trees affected by the disease exhibit wilt symptoms that include a black discoloration of the sapwood. Redbay trees and containerized seedlings died within 5 to 12 weeks after inoculation with the Raffaelea sp (Fraedroch et. al 2008). When redbay seedlings were challenged with X. glabratus, the beetles tunneled into 96% of the plants and 70% died (Fraedroch et. al 2008). Additional inoculation studies have shown that the Raffaelea sp. is pathogenic to sassafras, spicebush, and avocado and X. glabratus has been associated with their mortality. Preventing the spread of any invasive species involves learning more about how the species spreads and what can you do to stop it from multiplying. Invasive species move from an area of concentration by finding different hosts than their original host or, in this case, through the transportation of red bay wood. While it may be a major concern for naturalists it could also be a concern for the community. Many homes have seen the degeneration of their red bay trees and have wondered as to the cause and what treatments are available to save it from dying. Fortunately, there is research being done to find an effective way to deal with Xyleborus glabratus or otherwise known as the red bay beetle. Unfortunately, it may be too late based on the rate at which these beetles are dispersing. References Fraedrich, S. 2007. Laurel Wilt: Hosts and PathogenicityTests. USDA Forest Service. Fraedroch, S.W., T.C. Harrington, R.J. Rabaglia, M.D. Ulyshen, A.E. Mayfield, J.L. Hanula, J.M. Eickwort, D.R. Miller. 2008. A fungal symbiont of the redbay ambrosia beetle causes a lethal wilt in redbay and other lauraceae in the Southeastern United States. Plant Disease 92 (2): 215-224. Haack, R.A. 2006. Exotic bark- and wood-boring Coleoptera in the United States: recent establishments and interceptions. Canadian Journal of Forest Research 36 (2): 269-288. Hanula, J., B. Rabaglia, S. Fraedrich. 2007. Redbay Ambrosia Beetle Biology and Host Attraction. USDA Forest Service. Mayfield, A.E., M.C. Thomas. 2007. The Redbay Ambrosia Beetle, Xyleborus glabratus Eichhoff (Scolytinae: Curculionidae). Florida Department of Agriculture and Consumer Services. |