The first discovery of Asian longhorned beetle infesting trees in Ohio -- announced by the Ohio Department of Agriculture on June 17 -- points to a worrisome trend of exotic, invasive pests attacking the state's forests and urban tree resources while potentially dBeetle ealing yet another blow to nursery and forest-products industries, according to Ohio State University scientists.
A wood-boring insect from China first identified in the United States in New York City in 1996, ALB was found on three maple trees at a residence in Bethel, Clermont County, in southwestern Ohio. While the emerald ash borer (EAB) --another invasive beetle that hitchhiked its way to North America from Asia in wooden shipping material -- kills ash trees by feeding on the tissue right under the bark that transports water and nutrients, the ALB larva feeds on the interior of trees. Eventually, this causes the trees to lose their structural integrity, literally crumbling apart.
And unlike EAB (which only attacks ash trees), Asian longhorned beetles feed on a variety of hardwood trees, including maple, birch, elm, poplar, ash, horsechestnut and buckeye. Such feeding behavior makes ALB particularly dangerous.
"I had hoped that Asian longhorned beetle would never be detected in Ohio," says Dan Herms, an entomologist with OSU Extension and the Ohio Agricultural Research and Development Center and an expert on wood-boring insects. "ALB poses such a serious threat to Ohio's trees because it has a wide host range that includes maples, which are among the most abundant species in Ohio's natural and urban forests.
"Unfortunately, it is inevitable that invasive insects will continue to colonize Ohio and the rest of the U.S. as global commerce increases, and because agricultural inspectors are spread thinner and thinner due to the increased volume of imports and declining state and federal budgets to support their efforts."
According to ODA, if not controlled ALB could decimate maple trees in Ohio, impacting up to $200 billion worth of standing timber, adversely affecting maple sugar processors, damaging the state's multi-billion dollar nursery industry, and diminishing Ohio's popular fall foliage season. The U.S. Forest Service estimates there are more than 7 billion board feet of maple in the state.
However, the mere discovery of ALB in Ohio could have an immediate impact on the economy.
"Whenever this type of invasive insect is discovered, there follows a cascade of quarantines and restrictions on wood and tree products," said Dave Shetlar, an urban entomologist with OSU Extension and OARDC. "This has a major influence on nursery production companies, forest-products companies, landscape tree care companies, etc. I am hoping that we have discovered this infestation early enough that we can successfully eradicate it as was done in the Chicago area."
Unlike unsuccessful eradication attempts for EAB in Ohio and other infested states, ALB is being effectively contained in the other four states with known infestations (Illinois, Massachusetts, New Jersey and New York) and in Toronto, Ontario in Canada.
ODA and the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (USDA-APHIS) are now surveying the southern part of Bethel and the surrounding area to determine the extent of the infestation there. Crews will inspect tree species susceptible to ALB for signs of the insect, employing ground surveyors and specially trained tree climbers.
Federal and state officials are asking residents to help minimize the spread of ALB and other dangerous insects by not moving firewood (where larvae can hide unseen), choosing instead to obtain firewood locally when going camping or enjoying other activities outdoors.
"Community members can also help by being vigilant, checking their trees for symptoms of Asian longhorned beetle, and contacting the Ohio Department of Agriculture or OSU Extension if they find suspicious beetles or signs of an infestation," says Cindy Meyer, an agriculture and natural resources educator with OSU Extension in southwest Ohio. "In fact, the find in Clermont County was made possible by a homeowner who noticed something was wrong with his maple trees and contacted a forester with the Ohio Department of Natural Resources."
USDA is also enlisting the help of private citizens, the nursery and landscape industries, and natural resources professionals as "beetle detectives" --encouraging them to look for signs of ALB in their neighborhoods. Details on how to become involved are available at www.beetledetectives.com.
Residents who think they know of an ALB infestation are encouraged to call ODA's toll-free ALB hotline at 855-252-6450.
Community members in southwest Ohio who have questions about this beetle and its impact can call OSU Extension's Southwest Ohio Asian Longhorned Beetle Information Line at 513-946-8980.
Signs of ALB infestation include perfectly round exit holes (about 3/8 to 1/2 inch in diameter) made by adult beetles on the bark as they emerge from trees; notches or pockmarks on tree trunks and branches where female beetles deposit eggs; frass (wood shavings and sawdust) produced by larvae feeding and tunneling; early fall coloration of leaves or dead branches; and running sap produced by the tree at the egg-laying sites, or in response to larval tunneling.