During National Invasive Species Awareness Week, I had the good fortune to teach Indian Lake Central School’s 9th graders how to become beetle busters. On February 22, they discovered how invasive insects can cause economic, ecologic, and societal harm. For this lesson, we zeroed in on emerald ash borer and Asian longhorned beetle.
The class already had a solid understanding of what invasive species are because their teacher Sandra Bureau had been incorporating invasive species curriculum into their studies since September. Hands shot up when I asked for a definition. I detailed that Asian longhorned beetle and emerald ash borer probably hitched a ride from Asia to the United States in wood packing crates. Without the ecological checks and balances found on their home turf, they reproduce rapidly.
In the U.S., emerald ash borer and Asian longhorned beetle are transported to new locations in untreated firewood, green lumber, and contaminated nursery stock. Emerald ash borer infestations close to Hamilton County include those in Albany and Onondaga counties. Asian longhorned beetle has been found in Brooklyn and Queens, as well as on Long Island, and even closer in Worcester County, Massachusetts.
Students received a quick lesson in entomology and botany. Emerald ash borer and Asian longhorned beetle larvae kill trees by burrowing through xylem and phloem, the food and water transport systems of the tree. With aggressive infestations, trees can die in a few years. Emerald ash borer attacks ash species including white, green, and black. Host trees for Asian longhorned beetle include 13 hardwoods such as maple, elm, willow, and birch.
Students quickly realized how serious invasive insect infestations are. When asked, many students had played baseball with a wooden bat and all students loved maple syrup on their pancakes. Emerald ash borer and Asian longhorned beetle threaten the baseball bat, maple syrup, lumber, tree nursery, paper, and tourism industries. These beetles weaken trees, and limbs may fall on cars, homes, or power lines. Tree removal is expensive for homeowners and municipalities.
The morning was sunny and cold, and after covering the indoor lesson as fast as I possibly could, we laced up our winter boots, grabbed our jackets, and headed to the nature trail behind the school where students conducted an invasive insect forest survey.
The freshmen class looked for woodpecker damage, a great initial clue to an insect problem. Binoculars allowed for a zoomed in view of branches and trunks, allowing students to scan for exit holes that adult invasive beetles leave behind after chewing their way out through the bark. Asian longhorned beetles make round exit holes that are deep enough to hold a pencil, while emerald ash borers chew small, D-shaped exit holes.
Another sign students were on the lookout for was frass, or sawdust-like excrement produced by larvae. Asian longhorned beetle frass is often found at the base or in the crotch of an infested tree, while emerald ash borer frass is piled inside S-shaped galleries under the bark. They also checked for epicormic sprouting, or new branches produced at the trunk when the tree is stressed. No signs or symptoms of invasive insects were found during the forest survey.
At the end of the presentation, 9th graders became Beetle Busters armed with a toolbox to be proactive in invasive insect spread prevention. By not moving firewood and continuing to survey trees, they can stop the spread of emerald ash borer and Asian longhorned beetle. These enthusiastic students are the future stewards of our environment, and our environment is in excellent hands.
Visit the Hamilton County Soil and Water Conservation District’s website for more information about the signs and symptoms of invasive insects, and for a forest survey how-to video.
Photos: Above, the Beetle Busters of Indian Lake Central School learned how to check trees for invasive Asian longhorned beetle and emerald ash borer; middle, students scan trees for signs and symptoms of invasive insects; and below, a student uses binoculars to zoom in on signs and symptoms of invasive insects.