The Asian Longhorned Beetle (ALB) may not be in Iowa yet—but that doesn’t mean we shouldn’t be paying attention. This invasive pest has caused serious damage to trees in states like New York, Massachusetts, and Ohio. If it makes its way into our local forests or neighborhoods, the results could be devastating. Knowing what to look for and how to act can help protect your property and our environment.
What Is the Asian Longhorned Beetle?
The Asian Longhorned Beetle (Anoplophora glabripennis) is a large wood-boring insect that originally came from China and Korea. It likely entered the U.S. through wooden shipping materials and has since become a serious pest in several states.
The adult beetle is easy to recognize:
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It’s shiny black with white spots on its body.
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Its long antennae have black and white bands.
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It’s about 1 to 1.5 inches long—not counting the antennae.
Why It’s a Big Problem
ALB attacks many types of hardwood trees, including:
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Maples (especially Norway, red, and sugar)
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Elms
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Birches
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Horse chestnuts
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Willows
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Poplars
Once a beetle lays eggs inside a tree, the larvae tunnel deep into the wood. This feeding damages the inside of the tree, weakening its structure. Over time, this can cause branches to break off or the entire tree to fall. These trees often look healthy on the outside while the damage is hidden deep inside. That makes the beetle especially dangerous—it can kill trees without obvious signs until it’s too late.
Signs to Watch For
If you think ALB might be in your area or on your property, here are the top things to look for:
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Round exit holes in the bark, about the size of a pencil (⅜ to ½ inch wide)
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Oval pits or notches where the female lays her eggs
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Sawdust-like material (called frass) at the base of the tree or in branch crotches
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Dead or dying limbs, leaf drop, or thinning canopy
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Beetles themselves, especially during late summer
Treatments and Prevention
Currently, there is no guaranteed chemical treatment for trees already infested with ALB. The most effective control is removal and destruction of the infected tree before the beetles can spread.
However, for prevention and early-stage infestations, there are a few things you can consider:
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Imidacloprid – A systemic insecticide that can be injected into the soil or tree. It has shown some success in reducing larval survival but is not a cure once the beetles are deep inside the tree.
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Trunk injections – These are more direct but still limited in effectiveness, especially in large trees with heavy infestations.
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Regular inspections – Having a professional Certified Arborist inspect your trees regularly can catch signs of trouble before it’s too late.
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Proper tree care – Healthy trees are more resistant to pests. Regular pruning, watering, and avoiding soil compaction can help your trees stay strong.
What You Can Do
Even though ALB hasn’t been found in Iowa yet, the USDA and Iowa DNR are urging homeowners to keep an eye out. Here’s how you can help:
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Walk your yard and inspect your trees regularly, especially in late summer.
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Take photos of any signs you think could be ALB.
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If you think you’ve found one, report it immediately to the Iowa Department of Natural Resources or the USDA.
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Do not move firewood from one area to another—this is one of the fastest ways the beetle can spread.
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Hire a trained tree professional to help inspect and care for your trees.
Bottom Line
The Asian Longhorned Beetle is a real threat to our trees and our landscapes. If it spreads to Iowa, it could change the way our neighborhoods look for generations. Dead or damaged trees can also pose a major safety risk—especially in storms—so keeping your trees healthy and pest-free is more important than ever.
If you’re not sure what you’re looking at or you need help evaluating your trees, give us, Urban Tree Care of Iowa a call. We’re experienced, trained, and ready to help you protect your home, your trees, and your peace of mind.