Looking for the Emerald Ash Borer

by | Mar 27, 2013

A purple emerald ash borer trap, hung high in an ash tree.

You may have seen them hanging in trees along the side of the road: large, purple, sticky prisms. Based on appearance alone, you can probably think of more attractive things to hang in trees. But for the emerald ash borer, an invasive beetle that has already killed countless ash trees in the U.S., there could be nothing more attractive.

These purple prisms are traps for the emerald ash borer. Inside the trap hangs a lure that mimics the smell of ash trees, drawing the beetles in with an irresistible aroma. The purple hue of the trap is also visually attractive to the beetle. Like a moth to the flame, they are drawn to the trap, and eventually fly into and get stuck on its sticky sides. Surveyors from the NCDA&CS Plant Industry Division and the N.C. Forest Service will check the traps regularly and send “suspect” beetles — any beetle that looks like it might be an emerald ash borer — to an expert for verification.

The emerald ash borer is an invasive wood-boring insect that was first found in the U.S. near Detroit in 2002. It is thought to have arrived via wood packing material or products from Asia. Since its arrival, it has spread to many more states, leaving dead ash trees in its wake. All native ash trees are susceptible.

To date, the emerald ash borer is not known to occur in North Carolina, but it has been found in southern Virginia and eastern Tennessee. Because of our proximity to the infested areas in adjacent states, North Carolina is on the lookout. For now, these traps are the most effective option at detecting the beetles’ presence as it continues to migrate.

Traps started going up last week and will continue over the next few weeks. They will remain up during the active period of the adult beetle, which lasts through late summer.

Inspectors also are monitoring lumber shipped into the state. David Pearce, a plant protection specialist, recently spotted a load of infected ash logs during an inspection in Carteret County. The shipment was immediately quarantined and treated.

To help reduce the human-assisted movement of the emerald ash borer, all firewood should be burned where it is cut or purchased. If you see a suspicious insect, contact 1-800-206-9333 orĀ newpest@ncagr.gov. You can also contact your N.C. Forest Service county ranger for assistance.

Emerald ash borer adult. Image: David Cappaert, Michigan State University, Bugwood.org