Be on the lookout for the Asian Longhorned Beetle

In the war against the invasive Asian longhorned beetle (ALB), the U.S. Department of Agriculture recognizes August as ‘Tree Check Month’. Now is the best time of year look for this destructive wood-boring beetle, as the signs of ALB are most noticeable in late summer.

Asian longhorned beetle feeds on over 20 different tree species, with the potential to destroy millions of acres of hardwood forests in the U.S. The beetle’s preferred host is red maple, a widely popular urban tree species. Additional trees likely to be attacked by ALB include other maples, boxelder, buckeye, willow, elm, ash, birch, and sycamore.

While ALB has not been found in Missouri, the pest is easily transported into the U.S. in infested shipping materials, such as wood pallets and crating. This devastating pest can also travel from infested areas within the U.S. through the movement of firewood. Once introduced, eradication of ALB is possible, but it’s crucial that infestations are detected early. During eradication efforts, thousands of trees in the infested area are removed to prevent the spread of the beetle. Since its first introduction to the U.S., ALB has resulted in the death or removal of nearly 200,000 trees.

Help protect your community from the devastating effects of ALB by participating in Tree Check Month. Take an evening stroll through your yard or neighborhood, keeping an eye out for the large, showy beetle and the damage it causes to trees.

ALB has distinctive markings that are easy to recognize:

• Beetles are about 1 to 11⁄2 inches long.

• They have black, shiny bodies with distinct white spots.

• Antennae are long with black and white stripes.

• Beetles have six legs that can have a blue-tinged appearance.

The signs and symptoms of an ALB infestation in trees can include:

• Round, 1⁄2 inch diameter or dime-sized exit holes in tree trunks and branches.

• Small, shallow craters in the bark (about 1⁄2 inch wide) where female beetles have chewed egg sites.

• Sawdust-like material may collect around the base of tree trunks or branches.

• Leaves on some branches may show fall colors early.

In addition to checking trees, pool owners can help by watching for ALB in their pool filters. Suspect beetles should be reported as quickly as possible and can be stored in a plastic bag in the freezer. Report suspect beetles and infested trees, including photos, to MDC’s Forest Health staff at forest.health@mdc.mo.gov or by calling the invasive forest pest hotline at 1-866-716-9974.