The emerald ash borer has been detected in more than a dozen trees in the city of Milwaukee.
The Department of Agriculture, Trade and Consumer Protection confirmed the discovery of adult beetles on the city's north side. A city forestry work crew noticed several distressed ash trees while driving through a neighborhood along West Mill Road.
The tree-killing emerald ash borer has been confirmed in 12 Wisconsin counties: Brown, Crawford, Kenosha, La Crosse, Milwaukee, Ozaukee, Racine, Rock Vernon, Walworth, Washington and Waukesha counties.
DATCP said a quarantine is imminent for Rock and Walworth counties. Infestations were found in Janesville and Lake Geneva last month.
A quarantine means hardwood firewood cannot leave the area, no what the tree species is. Some businesses that use ash products are also affected by the quarantine.
DATCP said the quarantine should happen in the next few days, when the state's official newspaper publishes it.
Fond du Lac, Milwaukee and Sheyboygan counties are under quarantine.
For more information on EAB, click here.