MDA Expands War Against Gypsy Moths

New targets acquired, and MDA is on the hunt for further infestations.

Photo by I, Svdmolen. CC-BY-SA-3.0

ST. PAUL, Minn. – The Minnesota Department of Agriculture (MDA) announced Thursday it will be starting a new campaign against gypsy moth infestations, as well as a statewide survey to identify additional problem areas.

MDA will treat 791 acres north of Hinckley in order to eradicate the moth from the area. According to MDA’s press release, the area was identified as problematic by a survey conducted last fall.

Treatment will be conducted by aerial application of the bacterium Bacillus thuringiensis var. kurstaki (Btk.) The bacterium is approved for use by the U.S. Environmental Protection Agency, and has very low risk for humans or animals other than caterpillars. A helicopter will apply two doses to the area seven to 10 days apart, with the first treatment sometime between June 1 and June 15.

MDA has previously used this method across thousands of acres in Minnesota. MDA treated portions of the Richfield and Minneapolis areas earlier in May for gypsy moth infestations.

Gypsy moths are an issue due to their ravenous appetites, mainly targeting the leaves of many trees and shrubs. They mainly favor oak, poplar, birch, and willow trees. Severe repeat infestations can kill trees, and the gypsy moths can also be a nuisance to humans.

MDA will also be putting out 21,000 traps in the spring in an attempt to identify potential problem areas for gypsy moth populations. Personnel will begin putting out the traps May 25, with the instillations expected to take until the end of July. The traps contain a pheromone designed to lure in male gypsy moths.

“Our trapping survey program is an important frontline defense in the invasion of gypsy moth as they make their way across the country,” MDA Plant Protection Director Geir Friisoe said in a press release. “Each year we identify and treat start-up infestations, we save our urban and forested areas from a serious threat. This protects industries like tourism and forestry from economic harm and saves Minnesota from environmental damage.”

Gypsy moths have been a problem for many parts of the United States since their original introduction in New England. For example, the Iowa Department of Natural Resources estimated in 2011 that growing infestations could end up costing the state $22 million annually.

Anders Koskinen