MADISON – Emerald ash borer has been confirmed in Yellowstone Lake State Park, the first time the pest has been found in Lafayette County.
The county has been under quarantine for EAB since July 2014, so this new find does not change anything from a regulatory standpoint. However, actually confirming the presence of EAB should alert residents that it is more important than ever not to move firewood from the county to non-quarantine areas, officials say.
“We quarantined Lafayette County last July, along with Richland, Iowa and Green counties, even though we had no confirmed findings of EAB in those counties,” said Brian Kuhn, director of the Bureau of Plant Industry in the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP). “This block of counties was surrounded at that point by quarantined counties. Along with historic patterns of movement of wood products, that led us to suspect that EAB was present in low numbers that are difficult to detect.”
EAB has also now been confirmed in Green County. That confirmation came in April.
In the Lafayette County find, forest health staff from the Wisconsin Department of Natural Resources found four adult EAB beetles June 15 in a trap set in the park as part of a routine monitoring program.
DATCP sent the sample to the U.S. Department of Agriculture Animal and Plant Health Inspection Service for official confirmation, which was received June 17.
Quarantines prohibit ash wood products and hardwood firewood from being moved to areas that are not quarantined. For businesses handling wood products that could carry EAB, this means that they must work with DATCP to assure that they are not transporting the pest to non-quarantine counties. For private citizens, a quarantine means that residents may not take firewood from these counties to non-quarantine counties.
“We strongly discourage moving firewood even within quarantine areas,” Kuhn said. “The vast majority of EAB infestations have resulted from the movement of firewood, as evidenced by the number of times our first find in a given county has been in campgrounds. Most of the quarantined counties are not generally infested, so moving firewood within them could bring the pest to new areas in the county that would otherwise remain uninfested for several years.”
Kuhn notes that other forest pests and diseases also move easily and invisibly from one location to another under the bark of firewood.
DATCP recommends that property owners who have ash trees in quarantine counties:
-Keep a close watch for possible signs of EAB infestation: Thinning canopy, D-shaped holes in the bark, cracked bark, branches sprouting low on the trunk, and woodpeckers pulling at bark.
-Consider preventive treatments if your property is within 15 miles of a known infestation.
-Consider planting different species of trees that are not susceptible to EAB.
-Call a professional arborist, and visit emeraldashborer.wi.gov for detailed information.
Emerald ash borer 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 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, Manitowoc, Milwaukee, Monroe, Oneida, Outagamie, Ozaukee, Racine, Richland, 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. When the eggs hatch a week or two later, the larvae burrow under the bark for the winter and feed, forming the 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.
The Wisconsin Emerald Ash Borer Program includes DATCP; DNR; UW-Madison; UW-Extension; USDA Forest Service and Animal and Plant Health Inspection Service.