A foreign invader, despised for its ability to kill from the inside out as its larva feeds for months on living tissue, emerging as a grown adult as it bores a perfectly round hole to go on to the next host.

Sounds like a nightmare right? Unfortunately, this dream is a reality, one that now includes the Palmetto State. 

Asian Longhorned Beetles

The Asian Longhorned Beetle. So named for its nearly 4 inch long antennae, is one of the most destructive invasive species to certain trees, maples, willows, elms, and birch. It arrived in the US nearly 20 years ago via wood packaging material from China. Since then, the beetle has killed thousands of trees in several states, including Ohio, Massachusetts, and New York. Researchers recently discovered it for the first time in South Carolina earlier this year.

David Coyle, state extension specialist for South Carolina in the areas of forest health and invasive species, explains.

“We found it here at the end of May- we’re right now in the middle of what I call the hot zone. It’s a 22 square mile area that’s heavily infested in spots.”

Coyle has been leading the charge against this pest in Johns Island and Hollywood, the only known areas infested with the Asian Longhorned Beetle in the state. Every infected tree is marked with an orange dot- doomed and destined for removal, that is if they survive the damage the beetles have done to them.  

“If you look real closely you can see a tiny hole in the center. This is where that female laid an egg, then that larva feeds and feeds in there… they completely remove that wood. You get a lot of this sawdust and frass, which is a fancy entomology term for poop.”

He continues, “when they’re ready to come out they’ll make these nice round exit holes, it’s one of our telltale signs. There’s other beetles that may look like Asian Longhorned Beetles (ALB), but we’re looking for that perfectly round hole.”

Exit hole caused by ALB infestation

While the beetles don’t kill the tree directly, the structural damage they inflict is deadly- killing the tree by robbing it of water or weakening it so it falls from a strong breeze. 

Since there’s no cure once a beetle infests a tree, Coyle recommends South Carolinians should take action and check their trees for those signs and symptoms- the round exit holes, sawdust, frass,  and know the characteristics of the Asian Longhorned Beetle (ALB).

“The keys for this thing is it has black and white antennae, the feet have a bluish tint, a big black inch and a half beetle with white spots on it. If you have anything that you think may be this, please report it. We’d rather be safe than sorry on this one. You can email invasives@clemson.edu or you can call the Clemson Department of Plant Industry.”

David Coyle, Assistant Professor, Forest Health and Invasive Species Clemson University

Similar in size and color, the native cottonwood borer beetle may be mistaken for ALB, but it is predominately white with black spots.

You can also help by keeping this infestation contained by not moving firewood long distances. The Asian Longhorned Beetle and other invasive species are often transported this way- instead, buy or gather wood where you’ll burn it. Hopefully keeping this hot zone isolated in Charleston county. Because while there is no hope for these infected trees, there is hope in the fight against this invasive pest. 

“We’re lucky in this case that there’s a chance we can eradicate this and get it out of South Carolina. For a lot of the other really bad invasives, the Laurel wilt, the emerald ash borer- that’s never going to be gone. We have a chance to eliminate this one, it’s gonna take a lot of resources but it can be done.”

Storm Team 2 Meteorologist David Dickson