Skip to main content
Michigan’s nonpartisan, nonprofit news source

We need your vote!

During this important election year, Bridge readers like you know that high-quality journalism like ours is more critical than ever. There’s a lot on the line, and we’re working daily to deliver the information you need to prepare you for November’s election. Can we count on your vote of confidence in our newsroom? Donate today!

Pay with VISA Pay with MasterCard Pay with American Express Pay with PayPal Donate

Michigan warns residents to report invasive Asian longhorned beetle

Asian longhorned beetles are shiny black insects with white spots and long antennae
Asian longhorned beetles are shiny black insects with white spots and long antennae and are considered invasive because they chew on hardwood trees. (Courtesy of the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service )
  • Asian longhorned beetles are known for attacking hardwood trees 
  • They create tunnels inside of tree trunks during their larval stage and chew their way out as adults 
  • Residents are advised to report the invasive bugs by calling the U.S. Department of Agriculture’s Asian longhorned beetle hotline

Michigan state officials are warning residents to be on the lookout for an invasive, non-native beetle that is known for attacking 12 types of hardwood trees, some of which are found in the state. 

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service is advising residents to check their trees for the Asian longhorned beetle —  a black, shiny insect with white spots and black and white antennae — especially in August, which the USDA had designated Tree Check Month

The invasive insect is known for attacking 12 different types of hardwood trees including willows, birches and its favorite, maples, according to the Department of Environment, Great Lakes, and Energy. In Michigan, there are over 1 billion maple trees.

Sponsor

During their larval state, Asian longhorned beetles create tunnels in tree trunks and branches and then chew their way out of them when the insects reach adulthood during the summer. 

Related:

While Asian longhorn beetles have not been spotted in Michigan yet, state and federal agencies are urging residents to check for signs of an infestation, which can prevent damage to urban landscapes and maple syrup production. 

“It doesn't have predators,” said Nathaniel Walton, consumer horticulture educator at Michigan State University. “Birds that are used to it know how to eat it and so these kinds of organisms that we consider invasive … take over an area more quickly. They can kill trees more quickly because the trees don't have natural defenses.”

 A tree infested by the Asian longhorn beetle in Magdeburg. The beetle from Asia was first registered in Europe in 2001.
The trunk of a tree infested with Asian longhorn beetles. (Shutterstock)

Signs of an infestation could be exit holes, about the diameter of a pencil, near tree trunks, shallow round scars in tree bark, dead branches and wood-like shavings found near trees or branches. 

“The biggest risk is that it comes through … wood that's been harvested and turned into something else and then brought into Michigan without being checked for this beetle,” Walton said.

If you spot an Asian longhorned beetle or tree damage caused by the insect, you can report it by calling the USDA hotline at 866-702-9938 or submitting a report online

If you can, take a photo of the beetle or capture and freeze it for better identification. 

How impactful was this article for you?

Michigan Environment Watch

Michigan Environment Watch examines how public policy, industry, and other factors interact with the state’s trove of natural resources.

Michigan Environment Watch is made possible by generous financial support from:

Our generous Environment Watch underwriters encourage Bridge Michigan readers to also support civic journalism by becoming Bridge members. Please consider joining today.

Only donate if we've informed you about important Michigan issues

See what new members are saying about why they donated to Bridge Michigan:

  • “In order for this information to be accurate and unbiased it must be underwritten by its readers, not by special interests.” - Larry S.
  • “Not many other media sources report on the topics Bridge does.” - Susan B.
  • “Your journalism is outstanding and rare these days.” - Mark S.

If you want to ensure the future of nonpartisan, nonprofit Michigan journalism, please become a member today. You, too, will be asked why you donated and maybe we'll feature your quote next time!

Pay with VISA Pay with MasterCard Pay with American Express Pay with PayPal Donate Now