The Beetle Battle
Researchers Find New Weapon to Fight Infestation
Listen to Melissa Block's report
View a photo gallery of the beetle at different stages.
The Asian longhorned beetle.
Photo: U.S. Department of Agriculture
Egg-laying sites chewed out by female ALBs.
Photo: USDA Forest Service
These round exit holes are made by adult beetles as they emerge from the tree.
Photo: USDA Forest Service
June 25, 2002 -- The Asian longhorned beetle, native to China, has been lethally chewing its way through American hardwood trees since it was first discovered in the United States in 1996. Anoplophora glabripennis, an inky black insect with white spots, has been detected so far in New York City, where it's destroyed thousands of trees, and around Chicago. Experts worry that with no natural predators, the Asian longhorned beetle (ALB) could quickly spread and devastate hardwood forests.
The Department of Agriculture is searching for ways to stop the pest, and soon, they may have a new weapon in their arsenal: an acoustic detector that can hear the beetle larvae chewing deep inside a tree. NPR's Melissa Block reports for Morning Edition.
The traditional method of identifying infestation involves close visual inspection of host trees, such as maples, elms, poplars and willows. Block recently followed some inspectors on a hunt for the beetle, doing it the hard way -- they have to examine every branch and every trunk on suspected trees.
They search for egg sites -- dimpled impressions in the tree bark -- that signal that ALB larvae have worked their way inside the tree, and grown beetles have chewed their way out. The tunneling of the mature beetles kills the hardwood trees.
In addition to visual cues, inspectors may soon be able to locate the bugs by sound. Glenn Allgood, a senior researcher at Oak Ridge National Laboratory in Tennessee, has been listening to the chomping of Asian longhorned beetles, mapping the distinctive crunch of their mandibles as they bite off a piece of wood. "What we want to do is make a catalog of insect bites, if you will -- you know, their voices," he tells Block.
Using a little vibration sensor called an accelerometer, attached to a tree and hooked up to a computer, researchers can measure and record vibrations. The computer has been programmed with algorithms that define the exact feeding sound -- or signature -- of the ALB.
Scientists hope that this method will help locate and identify the destructive beetles, and two of the devices are to be tried out in New York City's Central Park this summer. However, Block reports, "others involved in fighting the ALB say the acoustic system is still highly experimental. They're putting their hopes in the old standby: visual inspection."
Photos of the Audio Beetle Detection System, with links to life cycle photos.
A wanted poster for the beetle.
U.S. Department of Agriculture: Animal and Plant Health Inspection Service photo gallery.
Pest Alert: Asian longhorned beetle (Anoplophora glabripennis).
Asian longhorned beetle information from the USDA Forest Service, including differentiating the ALB from other beetles.
The University of Vermont Entomology
Research Laboratory, which has been involved in efforts to eradicate the ALB since 1996.