Gypsy Moth Aerial Treatments to Resume Early Next Week

Release Date: June 20, 2017

Contact: Chris Foelker, (608) 224-4581,
             Bill Cosh, Communications Director, (608) 224-5020,

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MADISON -- Residents of nine western Wisconsin counties can expect to hear and see low-flying planes in the early morning, depending on weather conditions, starting next week. 

Small yellow planes will be applying mating disruption product specifically targeting gypsy moths. These invasive pests defoliate trees during their caterpillar stage, causing stress and potentially tree death.

From late June to late July, yellow planes contracted by the U.S. Forest Service in a joint project with the Wisconsin Department of Agriculture, Trade and Consumer Protection will be applying an organic, biodegradable mating disruptor to 19 sites in 9 counties in the western third of the state. 

Aerial treatments will be completed by the Slow the Spread Program. It focuses its efforts in western Wisconsin where gypsy moth populations are low or beginning to increase. The objective is to slow the westward spread of gypsy moth. The Slow the Spread treatments are planned in the following nine counties over the next four weeks: Buffalo, Chippewa, Crawford, Douglas, Dunn, Grant, Polk, Rusk, and St. Croix.

“Female gypsy moths do not fly. They give off a pheromone, or a chemical scent, which attracts male gypsy moths,” explained Christopher Foelker, DATCP’s gypsy moth program manager. “The product we apply to the tree canopy emits the same scent. These treatments are highly effective at reducing the mating success of this insect. The composition of the chemical signal released is specific to gypsy moth and will not interfere with the lifecycle of other insects.”

The gypsy moth has a wide range of harmful effects on local communities. The cost of removing dead trees around a house can range from several hundred to over a thousand dollars and the loss of mature trees decreases property value. During the spring and summer, caterpillars shed bristly skin as they grow. Bristles from the cast skins become airborne and can irritate eyes, skin and the respiratory system. People may develop a rash if they come in contact with the bristles.

About the Product

The product is aerially applied and dispersed across the forest canopy as small waxy droplets which slowly release the synthetic gypsy moth mating pheromone. Past research shows this can reduce gypsy moth populations by nearly 90 percent in the subsequent year.

The mating disruptor is not harmful to humans, animals, birds or other insects. According to the Environmental Protection Agency, there is no health risk to humans nor have any adverse effects been reported in the two decades that this pheromone has been used for gypsy moth control. 

Stay Updated

Treatment dates and times are weather dependent. People can sign up to receive email notifications about treatment plans at Daily updates during the treatment season are posted to DATCP’s Facebook and Twitter accounts. You can listen to a recorded message about the plans by calling the toll-free Gypsy Moth Information Line at 1-800-642-6684. Press menu option 1 for updates.

Treatments will begin in late June in southwestern Wisconsin and end in late July in northwestern Wisconsin. Maps of specific treatment areas are available online.


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