Emerald ash borer has been found for the first time in Winnebago County, and the county will join 18 others on the quarantine list in Wisconsin.
The tree-killing pest was found in the yard of a private home in the Town of Black Wolf on Aug. 1. A University of Wisconsin-Extension Service staff member in Winnebago County noticed signs of EAB damage, and notified the local forester with the Department of Natural Resources. He collected a larva, or immature EAB, at the site. The Wisconsin Department of Agriculture, Trade and Consumer Protection provided initial identification and U.S. Department of Agriculture gave final confirmation Aug. 6.
The quarantine will apply to all of Winnebago County. It prohibits wood products from being moved out of the county to areas that are not infested.
For private citizens, this means that they cannot take firewood from Winnebago County to non-quarantine counties. For businesses handling wood products that could carry EAB, it means that they must work with DATCP to assure that their products are pest-free before shipping.
The quarantine will be put in place temporarily by a Wisconsin emergency rule, until the U.S. Department of Agriculture completes the process to put a federal quarantine in place.
DATCP recommends that property owners who have ash trees in quarantine counties:
*Keep a close watch on ash trees for signs of possible EAB infestation: Thinning in the canopy, D-shaped holes in the bark, new branches sprouting low on the trunk, cracked bark, and woodpeckers pulling at the bark to get to insect larvae beneath it.
*Consider preventive treatments if your property is within 15 miles of a known infestation. Whether to treat depends on the age, size and number of ash trees. Treatment costs vary depending on size of the tree and whether you do the treatments yourself or hire a professional.
*Consider planting different species of trees that are not susceptible to EAB.
*Call a professional arborist for expert advice, and visit emeraldashborer.wi.gov for detailed information.
Emerald ash borer is native to China and probably entered the United States about 20 years ago on packing material, showing up first in Michigan about 10 years ago. It was first found in Wisconsin in 2008 in Washington County. Winnebago County will join 18 others under quarantine in Wisconsin: Brown, Crawford, Dodge, Fond du Lac, Jefferson, Kenosha, La Crosse, Milwaukee, Ozaukee, Racine, Rock, Sauk, Sheboygan, Trempealeau, Vernon, Walworth, Washington and Waukesha counties.
EAB adults lay eggs on the bark of ash trees in mid- to late summer. When the eggs hatch a week or two later, the larvae burrow under the bark for the winter and eat the wood, destroying the tree's ability to take up nutrients and water. In summer, the adults emerge through D-shaped holes in the bark.
The Wisconsin Emerald Ash Borer Program includes partners from the following agencies: Wisconsin Department of Agriculture, Trade and Consumer Protection; Wisconsin Department of Natural Resources; University of Wisconsin – Madison; UW-Extension; United States Department of Agriculture- Forest Service and Animal and Plant Health Inspection Service.