Asian Longhorned Beetle

“Just this past June, we confirmed a new infestation in South Carolina after a homeowner reported that they found a dead Asian longhorned beetle on their property,” said Josie Ryan, APHIS’ National Operations Manager for the ALB Eradication Program. “We need the public’s help to find new areas where the beetle has spread, because finding it sooner means less trees will become infested.”

The Asian longhorned beetle arrived in the U.S. via wood packing material from Asia. ALB has been reported in five other states (NY, MA, OH; eradicated in IL and NJ) and primarily feeds on maple, willow, elm and birch. In its larval stage, the insect feeds inside tree trunks and branches during the colder months. The beetle creates tunnels as it feeds, then it chews its way out as an adult in the warmer months. Infested trees do not recover and eventually die. Infested trees can become safety hazards since branches can drop and trees can fall over, especially during storms. Once a tree is infested with ALB, there is little that can be done other than removing the tree. Removed trees should be chipped or burned on-site, as it is possible to move ALB long distances in pieces of wood (e.g., firewood).

Spot a Killer

The beetle has distinctive markings that are easy to recognize:

  • Black and white antennae that are longer than the insect’s body.
  • A shiny black body with white spots that is about 1” to 1 ½” long.
  • Six legs and feet that can appear bluish-colored.  

SC Native Look-A-Likes

The cottonwood borer (left) is slightly larger than ALB (it can be ~2” long), is predominantly white with black spots, lacks the blueish feet, and has solid black antennae. The whitespotted sawyer (right) lacks white spots on the antennae and does not have bluish feet.

Check Your Trees

ALB infestations have already killed thousands of trees in 5 states and threaten trees in every state. Once a beetle infests a tree, there is no cure. Our best line of defense against this devastating pest is South Catolinians taking action and checking trees in their landscape for signs and symptoms of ALB. Symptoms of decline include:

  • Round exit holes in tree trunks and branches about the size of a dime or smaller.
  • Shallow oval or round scars in the bark where the adult beetle chewed an egg site.
  • Sawdust-like material called frass, laying on the ground around the tree or in the branches.
  • Dead branches or limbs falling from an otherwise healthy-looking tree.

What to Do

Do Not Move Firewood long distances – it can potentially transport invasive species. Instead, buy it where you will burn it, buy certified heat-treated firewood, or gather it on-site where permitted.

USDA APHIS and Clemson DPI are working on managing the current infestation in SC. If you think you see an ALB, please take pictures and if possible, capture suspicious insects in a durable container and freeze them, which helps preserve the insect for identification. Residents can report the insect or tree damage to the Clemson Department of Plant Industry (invasives@clemson.edu or by calling 864-646-2140) or your local Clemson Extension office, which can be found here

Additional ALB resources include:

Tidelines Editors

(Image Credits: aphis.usda.gov & hgic.clemson.edu)