LEWISTON — So far, Maine has been spared from infestations from two hardwood-eating beetles and conservation officials hope to keep it that way.
“We’re concerned about these particular beetles because they both attack healthy trees,” said Karen Coluzzi, Maine Department of Agriculture entomologist. “And, there is no known natural control for them.”
Populations peak for both the Asian long-horned beetle and the emerald ash borer in late summer and early fall and that has conservation officials eager to get out in the field and see if they can find any.
Coluzzi will be leading a survey around the Bates College campus on Tuesday. The survey was originally scheduled for last week but was postponed by rain twice.
The beetles do fine in the rain, she said. Coluzzi said she was more concerned about the volunteers when she postponed the survey.
“Both are hard to find, and we end up looking up at trees with binoculars, looking for evidence,” she said. “That’s hard to do with rain pelting down on your face.”
Both bugs shun evergreens and the adults peak around the early fall, but Coluzzi said they are very different.
Asian long-horned beetles are large, with bodies of an inch or longer and antennas as long as their bodies. They are shiny black with white spots and attack hardwood trees — but never oaks, apples or cherries.
“There is a native long-horned beetle that looks very similar, but it attacks conifers and only dying ones,” she said. “We don’t consider that one a threat.”
The emerald ash borer is smaller and eats only ash trees. It metallic-green body is about half-an-inch long but it lives mostly in the canopies of ash trees.
“You won’t notice it — just the damage it does,” she said.
Both have caused big problems in the Midwest states and western Massachusetts.
“Probably, the emerald ash borer is the more elusive beetle,” she said. “It travels easily on firewood and kills trees quicker. You don’t realize you have a problem until your trees are dead.”
The Asian long-horned beetle first came to the United States about 20 years ago, hitchhiking on wooded packing crates.
“They tend to stay in the same area with multiple hosts,” she said. “If they are on an ash and the next tree is maple, they’ll just move right on to the maple.”
Ash borers kill ash trees from the top down, leaving eighth-inch wide holes around the outside of the tree. Long-horned beetles leave wider holes behind and oval shaped egg sights scratched into branches.
The only sure way to get rid of an infestation is get rid of the infected trees, she said.
The survey is a chance for conservation officials to hunt for the bugs and to spread the word about them, she said. People who suspect they have infested trees should contact her office at 287-3891.
“We need them to collect the bugs if they can, or take a picture,” she said. “We need some way to identify the suspects.”
People interested in helping with Tuesday’s survey should call 287-3892 to register.
-
- The Emerald Ash borer, shown by Maine State Forest Entomologist Colleen Teerling in August of 2009, targets Ash trees, killing them. So far, the invasive species has not been found in Maine.
-
- A dead Asian long-horned beetle is seen in its adult stage, front, and as a larva at the state Department of Resources and Economic Development Division of Forest and Lands office in Hillsboro, N.H. The beetle has spared Maine’s trees thus far.
Send questions/comments to the editors.
