story to find out more.
Adult Asian longhorned beetle feeding on a twig of
a potted Acer mono sentinel tree. Click the image for more
information about it.
To Bag a Bad Beetle, Researchers Tap Forensic
By Erin Peabody
May 4, 2006
Tracking the elusive Asian longhorned
beetle (ALB) could soon get a whole lot easierand weirder. Agricultural
Research Service (ARS) scientists have
developed a novel "fingerprinting" tool that relies on analyzing, of
all things, the invasive beetle's droppings to help give it away.
According to ARS insect geneticist
Hunter, what's so telling about the insect's "frass," is that it
has a genetic signature that's totally unique to the beetle. Hunter works in
Insects Research Unit at Fort Pierce, Fla.
So Hunter, with help from ARS insect behaviorist
T. Smith, developed genetic markers that can be used to screen frass found
on trees known to attract ALB. If a sample matches the insect's established
genetic profile, beetle hunters will know they've got a potential infestation
on their hands. Frass is only one sign of an ALB infestation. Beetle hunters
also look for the dime-sized, perfectly round holes left by emerging adult
beetles, as well as pits that mark locations where eggs have been laid.
Two things make the ALB one of the country's most "wanted"
invasives. First, its ravenous appetite for hardwoodslike maple, elm and
birchthreatens forests and tree-lined neighborhoods across the East.
Second, a quiet killer, the beetle inflicts its greatest damage while hidden
deep inside trees. Immature ALBs create elaborate tunnels while feeding there,
weakening trees until they finally snap in half or must be cut down.
Adding to the ALB toolbox, Smith has also developed a method for detecting
the alien insect. Smith, who works in the ARS
Insects Introduction Research Unit at Newark, Del., has shown that a
chemciala pyrethroid called Demandcan knock down adult, free-flying
beetles in just minutes.
Using the insecticide as a fast-acting detector, beetle-hunting crews could
simply spray trees suspected of harboring the insects and wait for the bugs to
fall. Now, crews climb trees one by one and scrutinize bark for the faintest
signs of ALB activity.
Officials with the ALB Cooperative Eradication Program--administered by the
Animal and Plant Health Inspection Service--believe the new technique could
have a limited application in certain circumstances in the detection component
of the program and are evaluating its potential impact on the human and natural
more about the research in the current issue of Agricultural
ARS is the U.S. Department of
Agriculture's chief scientific research agency.