Asian Giant Hornet Found in North America, Not Yet Iowa

Keep an eye out for new type of hornets, but don't panic

May 13, 2020, 8:25 am | Laura Jesse Iles, Donald Lewis, Zach Clemens

AMES, Iowa – News of the Asian Giant Hornet’s arrival in Washington state has spread a lot farther than the actual invasive insect, and there is no evidence it has arrived in Iowa or will ever be here, according to Iowa State University Extension and Outreach specialists.

The Asian Giant Hornet, Vespa mandarinia, checks in at more than two inches, which makes it the world’s largest. It carries a painful sting and could have a serious detrimental impact on honey bee populations.

Washington State Department of Agriculture verified two reports of the AGH near Blaine, Washington in December, and a nest was discovered — and quickly destroyed — in British Columbia earlier this year. Entomologists in Washington are on alert, and to identify AGH they are surveying with traps and relying on reports from citizens.

Asian Giant Hornet.Female AGH make their nests in the spring, but in the fall is when it is more likely that they may attack honey bee colonies.

Iowa State University and the Iowa Department of Agriculture and Land Stewardship are monitoring observations and reports about AGH to help assess the threat to Iowans. Iowans are invited to contact the Iowa State University Plant and Insect Diagnostic Clinic for help identifying suspect specimens. Because Iowa State is mostly operating remotely, contacts via email are more efficient than phone calls.

If a clear picture can be safely taken, send the image to Use extreme caution; photograph a suspect that is already dead or can be safely killed with spray or swatter. If a picture is not available carefully record detailed observations such as size, shape and colors. 

Donald Lewis, extension entomologist at Iowa State University, urges Iowans to watch for this and other invasive species and to report insects that seem out of the ordinary. 

“The discovery of AGH in Washington and British Columbia late in 2019 is another concern but not a reason to panic,” Lewis said.

According to Randall Cass, entomologist with ISU Extension and Outreach, it is unclear whether the AGH would find Midwestern habitats suitable, but for now, it is not the biggest worry for beekeepers. A much more relevant concern for honey bees is the destruction of pollinator habitat.

The arrival of the AGH is an unwanted, but not entirely unexpected development. Fortunately, there is no evidence of the presence of AGH in Iowa.  Iowans are encouraged to continue learning about AGH and to report suspicious insects.

For more information, visit the Washington State Department of Agriculture, the Washington State University Extension or the Smithsonian Magazine article, “No, Americans Do Not Need to Panic about ‘Murder Hornets.’”


Original photo: Asian Giant Hornet. Photo courtesy of Washington State Department of Agriculture.

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