Emerald ash borer detected in Washburn County

The state Department of Natural Resources detected the presence of emerald ash borer for the first time in two northern Wisconsin counties.

DNR staff members collected larvae samples in the town of Springbrook in Washburn County, as well as in Medford in Taylor County. A USDA Animal and Plant Health Inspection Service identifier confirmed these larvae as EAB. Burnett is now the only county without a detection since EAB was first discovered in Wisconsin in 2008.

The detections will not result in regulatory changes because EAB was federally deregulated on Jan. 14, 2021, and Wisconsin rescinded its statewide quarantine effective July 1.

EAB will continue to spread in northern Wisconsin, significantly impacting the state’s ash resource. In Barron County emerald ash borer was first detected in 2021, with the town of Lakeland the only location in the county found to have the invasive species, according to the Wisconsin EAB Online Detection map.

DNR’s updated EAB webpage, which can be found by searching emerald ash borer on the DNR website, includes information and resources on this invasive species.

For those looking for treatment options, UW-Madison’s EAB webpage at eab.russell.wisc.edu provides information on insecticide treatment for ash shade trees.

A total of 66 new municipal detections have already been reported in 2024, and map updates continue to occur regularly. To view where EAB has been found in Wisconsin or to report new detections, visit datcpservices.wisconsin.gov/eab/index.jsp.