News Releases


Gypsy Moth Spraying Planned in Polk County; Environmental Assessment Open for Comment
May 24, 2013

Gypsy Moth Spraying Planned in Polk County; Environmental Assessment Open for Comment (1 page PDF)

Contact:  Donna Gilson, 608-224-5130,
             Jim Dick, Communications Director, 608-224-5020,

MADISON – Aerial spray treatments to destroy a population of gypsy moths in Polk County will benefit local businesses and residents, and will not harm the environment.

That is the finding in an environmental assessment required by the Department of Agriculture, Trade and Consumer Protection.

Members of the public can comment on the environmental assessment until Friday, May 31. The assessment, including a map of the site, is available online. Copies are also available by contacting Rick Hummell, or 608-224-4891. Comments may be emailed to Hummell or mailed to him at DATCP-ARM, P.O. Box 8911, Madison, WI 53708-6777.

The 901-acre site in central Polk County includes land on either side of 220th Avenue. It will be sprayed twice, 5-10 days apart, in June with Foray 48B. The active ingredient in Foray 48B is Bacillus thuringiensis var. kurstaki, or Btk. This biological pesticide contains a common soil bacteria that is fatal to the caterpillars of gypsy moths when they eat leaves sprayed with it. While it may also harm other species of caterpillars, no threatened or endangered species are in the area to be sprayed. Residents in the area have been notified of the plan by postcard.

Gypsy moth caterpillars feed on the leaves of hundreds of species of trees and shrubs. High populations defoliate trees, leaving them susceptible to other pests and diseases that may kill them. When populations become established in an area, that county is quarantined. In addition, tourism may suffer.  Droppings and hairs from high populations of gypsy moth caterpillars during outbreaks can cause human health effects, including skin lesions, eye irritation, and respiratory problems. 

Without this treatment, Polk County would likely be quarantined in the next year. That would mean that timber-related industries, Christmas tree growers, and nurseries have to follow regulations to move their products and might have to apply pesticides before doing so.

The gypsy moth infestation found in Polk County is isolated from the other areas of Wisconsin with scattered gypsy moth populations, indicating a westward spread, and from quarantined counties that are generally infested with gypsy moth.


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