Big things come in small packages, and that is certainly true in the case of laurel wilt disease, though not in a good way. The tree-killing disease has already killed an estimated half a billion redbay trees across the Southeast. This big problem is caused by tiny culprits, a poppy seed-sized beetle and microscopic fungal spores it carries. And it keeps spreading to new areas.
This month, laurel wilt was confirmed in Lenoir County for the first time, making it the 11th county in N.C. to be positive for the tree-killing disease.
Laurel wilt is a devastating disease of redbay trees and other plants in the laurel family. The disease is caused by a fungus which is moved from tree to tree by the redbay ambrosia beetle. Native to southeastern Asia, the beetle was first detected in the U.S. near Savannah in the early 2000s. It has since spread to eight additional states, from Texas to North Carolina.
Each year, winter surveys are conducted to assess the spread of laurel wilt in N.C. In January 2019, forest health professionals detected the new site in Lenoir County during routine surveys. Samples were sent the NC State’s Plant Disease and Insect Clinic where the culprit was confirmed as laurel wilt.
Laurel wilt kills trees in just a few weeks. The fungus-toting beetle primarily attacks redbay and sassafras, but other lauraceous plants are also at risk. Last year, it was confirmed in sassafras in N.C. for the first time. While redbay trees are not a high-value timber species, they provide food and shelter to many animals, including songbirds, turkeys, quail, deer and bears. A couple of swallowtail butterflies rely almost exclusively on plants susceptible to laurel wilt, endangering their continued existence. There are also two rare plant species that are known to be susceptible to laurel wilt: pondspice and pondberry.
Currently, there is no reliable way to prevent or treat laurel wilt. Insecticides have not been effective in stopping beetle attacks, and fungicides are costly and need re-application. Our best weapon is slowing the spread, so please use local or treated firewood and notify your N.C. Forest Service county ranger if you suspect laurel wilt has invaded a new area. The most up-to-date range map can be accessed on the N.C. Forest Service’s website.