The Asian longhorn beetle (ALB) is one of the biggest threats to trees in this country. This invasive insect, first discovered in the U.S. in 1996, arrived accidentally from Asia in wood cargo packing. It attacks a wide range of deciduous hardwood trees, including ash, maple, elm, birch, horsechestnut, sycamore, willow, and poplar. Since its arrival in this country, it has led to the loss of nearly 130,000 hardwood trees, and hundreds of millions of dollars have been spent in efforts to control infestations in Illinois, New Jersey, New York, Ohio and Massachusetts. Forty-five other states are currently considered at-risk for infestation.
The rather striking looking adult beetles are bullet-shaped, 1-1/2 inches long, glossy black with irregular white spots. Their size may give you pause, but they are harmless to humans and pets, and don't bite or sting. Their most distinctive feature is their 2-inch long antennae banded with black and white. But it's the white, worm-like larvae that hatch from eggs deposited within the tree that do the damage, tunneling deep into live trees and eventually killing them by destroying their water and nutrient conducting tissues.
One of the best ways to halt the spread of this pest is to enlist the help of the public in locating new infestations. In fact many initial infestations were found by members of the public, not by pest specialists. To encourage people to check trees on their property and in their community, the USDA has designated August as Tree Check Month. They are asking everyone to take even just 10 minutes annually to check trees for both the adult ALB and any signs of the damage to trees, then report possible infestations. What are you looking for? Besides the beetle itself, look for round, pencil eraser to dime size exit holes on the tree, shallow pitted scars in the bark, sawdust like material on the ground or tree branches, and dead branches in the crown of the tree.
Another important way to help is by not moving firewood. Purchase it where you will burn it to avoid inadvertently moving the ALB to an uninfested area. States currently fighting the ALB -- Massachusetts, New York, and Ohio -- have quarantines in place and special guidelines for handling wood. Check with local authorities for more information.
To learn more about the ALB; how to identify it and signs of tree damage; what trees are at risk; how to report a possible infestation; and what else you can do to protect trees and make others aware of the danger, go to the USDA's Asian Longhorned Beetle. (Image courtesy of U.S. Dept. of Agriculture).