Adult ALB.
David Coyle, ©2021, Clemson Extension
It’s been 1-year since the Asian longhorned beetle (ALB) was found in Charleston County. This invasive species is mostly a threat to maples but also to poplar, willow, sycamore, birch, and elm. Japanese maple, a common landscape tree, does not seem to be impacted. Feeding by the larvae creates large tunnels in the wood, often resulting in breaking stems and branches. The large black and white adults are visually striking, but surprisingly can be difficult to find on the trees.
Arrows point to ALB larval feeding galleries, which weaken tree stems and branches, often resulting in breakage.
David Coyle, ©2021, Clemson Extension
Broken branch resulting from ALB larval feeding.
David Coyle, ©2021, Clemson Extension
The Clemson Department of Plant Industry (DPI), USDA Animal and Plant Health Inspection Service (APHIS), and Clemson Extension have all been working collaboratively to launch and maintain the state’s ALB eradication program. Much information about the beetle, the damage it causes, and the quarantine can be found at www.clemson.edu/public/alb.
So far, USDA APHIS, Clemson DPI, and SC Forestry Commission personnel have surveyed over 40,000 trees across Charleston and Dorchester counties. APHIS also monitors the completion of tree removals performed by the Davey Resource Group – at this point, the only way to get rid of ALB is to remove and destroy infested trees. Clemson DPI personnel have coordinated resource-sharing trainings with colleagues from surrounding state agencies and lead efforts to help local tree and landscape companies become compliant with recent regulations. Clemson DPI also works with Clemson Extension to educate landowners and tree care professionals. Researchers from the Department of Forestry and Environmental Conservation have begun multiple research projects investigating how ALB spreads, their rate of development, and alternate management strategies.
In the meantime, life in nature goes on! Many of the ALB eggs laid last summer and fall have now fully undergone larval development and pupation. Adult beetles are actively chewing out of round holes (large enough to hold a No 2 pencil or ballpoint pen) and flying to find mates. If you live in (or are traveling to) Charleston or Dorchester counties, please keep an eye out for large-bodied black beetles with white spots and long antennae (more descriptions and where to find it at: https://www.aphis.usda.gov/aphis/resources/pests-diseases/asian-longhorned-beetle/Find-It) and report your sightings if you believe you’ve found ALB by emailing stopalb@clemson.edu or calling 843-973-8329. This is one of the worst times of year to be transporting untreated wood like firewood as beetles can quickly establish a new population to new areas once relocated, so please remember #DontMoveFirewood!
Adult ALB chewing through the bark of a red maple tree.
David Coyle, ©2021, Clemson Extension
Adult ALB crawling its way out of an infested red maple tree.
David Coyle, ©2021, Clemson Extension
