Look for signs of invasive Asian longhorned beetle

August is Tree Check Month

Photo of Angela Mulka

Last year, the U.S. Department of Agriculture declared August as tree check month in an effort to save trees from invasive pests, like the Asian longhorned beetle.

Though not yet detected in Michigan, the Asian longhorned beetle is on the state’s invasive species “Watch List” because our trees have little to no resistance to infestation. If an Asian longhorned beetle infestation is reported, federal and state officials will begin survey and eradication activities, including destroying all infested trees. Tree removal is unpleasant, but it has been successful in eradicating Asian longhorned beetle populations in neighboring states.

Populations of this beetle are known to be present in Ohio, Massachusetts and New York, and have killed more than 130,000 trees. If this large, showy beetle makes its way into Michigan and across North America, the economic and ecological impacts would be enormous, according to the State of Michigan

There are more than 1 billion maple trees growing in Michigan, which is the Asian longhorned beetle’s favorite host. That is why the Michigan Department of Natural Resources is urging people to check their trees. Early detection is critical, according to the State, because once a beetle infests a tree, there is no cure.

“We’re asking for the public’s help to find Asian longhorned beetle and any tree damage it causes, because the sooner we know where the insect is, the sooner we can stop its spread,” said Josie Ryan, Animal and Plant Health Inspection Service’s national operations manager for the Asian longhorned beetle eradication program. “Just last year, a homeowner in South Carolina reported finding a beetle in their backyard, which led us to discover an active infestation in the state where we didn’t know the beetle was.”

The adult beetle has distinctive markings that are easy to recognize:

• A shiny black body with white spots that is about 1-inch to 1 1/2-inches long.
• Black and white antennae that are longer than the insect’s body.
• Six legs and feet that can appear bluish in color.

Report any Asian longhorned beetle sightings

Report any Asian longhorned beetle sightings here or call 1-866-702-9938 to report by phone.

Pay attention to trees, especially maples with dying branches, and check your trees for these signs: 

• Dime-sized exit holes in tree trunks and branches.
• Shallow scars in bark.
• Sawdust-like material on ground or tree branches.
• Dead branches or limbs falling from an otherwise healthy-looking tree.
• The beetle itself.

You can report your sightings at AsianLonghornedBeetle.com or call 1-866-702-9938 to report by phone. August is the most critical time of year to spot the beetle as adult activity peaks.

The beetle was accidentally introduced to the U.S. on several occasions, probably in wood crating or pallets shipped from Asia. The Asian longhorned beetle feeds on a wide variety of popular hardwood trees, including maple, birch, elm, willow, ash and poplar. More than 12 different types of trees are in jeopardy when it comes to this invasive species, according to the U.S. Department of Agriculture.

For more information about the Asian longhorned beetle, visit here