The emerald ash borer (Photo: DATCP)
A destructive pest continues to spread across Wisconsin. Routine trap monitoring confirmed the tree-killing emerald ash borer in Richland County, and in Marquette County, which will become the 38th Wisconsin county to be quarantined for EAB. Richland County remains under a previous quarantine.
The state Department of Agriculture, Trade and Consumer Protection (DATCP) said confirming the presence of EAB should alert residents that it is more important than ever not to move firewood to non-quarantine areas. Commercial ash products must be certified as pest free before they can sold in non-quarantined counties.
Emerald ash borer is native to China. The insect first showed up in Michigan in 2002 and likely arrived in the U.S. in packing material. It was first found in Wisconsin in 2008 in Ozaukee County.
Other quarantined Wisconsin counties are Adams, Brown, Buffalo, Calumet, Columbia, Crawford, Dane, Dodge, Door, Douglas, Fond du Lac, Grant, Green, Iowa, Jefferson, Juneau, Kenosha, Kewaunee, La Crosse, Lafayette, Manitowoc, Milwaukee, Monroe, Oneida, Outagamie, Ozaukee, Racine, Rock, Sauk, Sheboygan, Trempealeau, Vernon, Walworth, Washington, Waukesha and Winnebago.
EAB adults lay eggs on the bark of ash trees in mid-to late summer. The eggs hatch a week or two later, and larvae burrow under the tree bark for the winter and feed, forming characteristic S-shaped tunnels and destroying the tree’s ability to take up nutrients and water. The following summer, the adults emerge through D-shaped holes in the bark.