Emerald ash borer discovered in 5 new Wisconsin counties

Emerald ash borer

MADISON — The emerald ash borer (EAB), a destructive insect of ash trees, has been confirmed in five new Wisconsin counties, including two norther counties. The Wisconsin Department of Agriculture, Trade and Consumer Protection reports Tuesday, September 5th they will quarantine all five.

According to a news release, the new counties are Chippewa, Green Lake, Marinette, Waupaca and Waushara. The Chippewa County infestation was discovered by a homeowner on private property where trees were dying. The other four were finds in monitoring traps set by the USDA-APHIS and the Wisconsin Department of Natural Resources.

“These new finds fill in the map for the southern two-thirds of the state, and add to the checkerboard of quarantined counties in the north,” said Brian Kuhn, Plant Industry Bureau Director with DATCP.

“However, many of the quarantined counties are not generally infested. This is a pest that’s largely been spread by humans. People still need to use certified firewood that has been treated or seasoned to ensure it’s not infested with live pests. If they use uncertified firewood, they should burn it where they buy it, and not move it even within quarantined areas. That will help slow the spread of EAB and the many other pests that firewood could carry.”

Details of the new finds:
Chippewa County A Lake Wissota homeowner in the Town of Lafayette reported dying trees, and DNR staff collected EAB larvae, or immature insects. This infestation appears to have been present for several years.

Green Lake County Adult emerald ash borers were found in traps in two different townships: The Town of Green Lake, in the right of way along St. Marie Road just north of Highway 23, and in the Town of Brooklyn, in Margaret Dodge Memorial Park.

Marinette County Adult emerald ash borers were found in traps in three different locations: On Ridge Street in Niagara, County Rd RR in the Town of Wagner, and on South Hilbert Road in the Town of Goodman.

Waupaca County An adult EAB was collected in a trap in the right of way along County Road Q, just south of Highway 10 in the Town of Farmington.

Waushara County An adult EAB was collected from a trap in the right of way along Beechnut Avenue, just west of County Road V in the Town of Deerfield.

For private citizens, the quarantine means that they cannot take firewood from quarantined counties to non-quarantined 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.

For property owners in these and other quarantine counties, Kuhn recommends:

  • Watch 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.
  • If your property is within 15 miles of a known infestation, consider preventive treatments. Whether to treat depends on several factors: the age of the trees, the size of the trees, and the number of 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.
  • Contact a professional arborist for expert advice, and visit emeraldashborer.wi.gov for detailed information.

EAB is native to China and probably entered the United States on packing material, showing up first in Michigan in 2002. It was first found in Wisconsin in 2008 in Washington County. The five new counties joins 41 other Wisconsin counties where EAB has been found: Adams, Brown, Buffalo, Calumet, Columbia, Crawford, Dane, Dodge, Door, Douglas, Fond du Lac, Grant, Green, Iowa, Jackson, Jefferson, Juneau, Kenosha, La Crosse, Lafayette, Manitowoc, Marquette, Milwaukee, Monroe, Oneida, Outagamie, Ozaukee, Portage, Racine, Richland, Rock, Sauk, Sawyer, Sheboygan, Trempealeau, Vernon, Walworth, Washington, Waukesha, Winnebago and Wood. Kewaunee County is also under quarantine because of the proximity of infestations in neighboring counties.