Wisconsin DNR: Emerald ash borer confirmed in all of state's counties

Emerald ash borer confirmed in all counties

The Wisconsin Department of Natural Resources confirmed the detection of emerald ash borer in Burnett County. That means the pest has now been confirmed in all 72 of the state's counties.

MADISON, Wis. - The Wisconsin Department of Natural Resources (DNR) confirmed on Friday, July 26 the detection of emerald ash borer (EAB) in Burnett County. That means the pest has now been confirmed in all 72 of Wisconsin’s counties.

A news release says DNR staff responded to a report of EAB at a private residence in the Town of Meenon on June 13. Two trees on the property showed characteristic symptoms of EAB infestation, including tree decline and visible woodpecker damage to the outer bark, known as "flecking."

The state’s first confirmed sighting of EAB took place in Ozaukee County in July 2008. Although the ash tree-killing beetle is less established in northwest Wisconsin than in other parts of the state, officials said this year’s detections indicate that the pest is expanding its foothold in the region. EAB is usually transported to new areas by hitching a ride on firewood.

SIGN UP TODAY: Get daily headlines, breaking news emails from FOX6 News

Emerald ash borer (Terry Harris/Chicago Tribune/Tribune News Service via Getty Images)

DNR officials say EAB larvae bore into ash trees and carve winding, S-shaped galleries beneath the trees’ bark, typically starting in the upper canopy and progressing down the tree. The galleries restrict the movement of water and nutrients to affected areas of the tree, leading to branch dieback, canopy thinning and tree death.

EAB is expected to eventually kill more than 99% of Wisconsin's white, black and green ash (and their ornamental varieties). Landowners concerned about EAB should contact a forestry professional or ISA-certified arborist and consult the state’s EAB Information Resource webpage to learn about management options. In the parts of northern Wisconsin where EAB populations remain low, there is still an opportunity to reduce the insects’ impact.

The Burnett County detection will not result in any federal regulatory changes. EAB was federally deregulated on Jan. 14, 2021, and Wisconsin rescinded its state quarantine on July 1, 2023.