DATCP to Aerial Spray for Gypsy Moth in 18 Counties

Release Date: April 27, 2020

Media Contacts:

Stephanie Jentz, Gypsy Moth Public Information Officer, (608) 347-1082

Leeann Duwe, DATCP Public Information Officer, (608) 224-5130

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MADISON – Starting in May, the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) will spray for gypsy moth in 18 western Wisconsin counties. Residents in the affected areas listed below can expect loud, low-flying, small, yellow planes as early as 5 a.m.

“Aerial spraying is the most efficient and effective treatment method to help slow the spread and delay the impacts associated with gypsy moth outbreaks," said Christopher Foelker, DATCP's gypsy moth program manager. “It's important to slow this invasive pest. Well-established gypsy moth populations cause damage to forests which impacts natural resources, wildlife, tourism, and the timber industry." 

Aerial spraying in western Wisconsin will focu​s on where gypsy moth populations are low or beginning to build, in an attempt to slow them from moving further west. Spraying is scheduled for the following counties: Bayfield, Buffalo, Burnett, Chippewa, Crawford, Douglas, Dunn, Grant, Green, Iowa, Lafayette, Polk, Richland, Rusk, Sawyer, Trempealeau, Vernon, and Washburn. DATCP's plan is to start in southern Wisconsin in mid-May and end in the northern part of the state in July. Maps of treatment areas are available at https://datcpgis.wi.gov/maps/?viewer=gm

The ability to spray is dependent on when caterpillars hatch and weather conditions (calm, no precipitation, low humidity). Planes fly low just above treetops so the treatment reaches the canopy leaves where caterpillars feast. From mid-May to early June, planes will spray a treatment called Bacillus thuringiensis var. kurstaki (Btk) to kill caterpillars. Btk is made from a naturally-occurring soil bacteria and is used in certified organic food production. It is not toxic to people, bees, pets, or other animals. However, people with severe allergies may prefer to stay indoors during nearby treatment applications. In late June to early July, planes will spray a gypsy moth pheromone that prevents the adult male gypsy moth from searching for a female to reproduce. The mating disruptor is organic and biodegradable. 

For more information, visit https://datcp.wi.gov/Pages/Programs_Services/GMAerialSpray.aspx. To receive up-to-date information on treatment plans during the spray season, you can do any of the following:


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