Wisconsin DATCP: Spongy moth aerial treatments to resume in late June


Morgan Cavitt, Public Information Officer, (608) 852-7438, [email protected]

Stephanie Jentz, Plant Industry Public Information Officer, (608) 347-1082, [email protected]

MADISON, Wis. – The Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) plans to treat 32 sites across 15 western Wisconsin counties for spongy moth, formerly known as gypsy moth, starting in late June. Residents can expect to see and hear loud, low-flying planes as early as sunrise.

From late June to mid-July, planes will spray an organic, biodegradable mating disruptor containing spongy moth pheromone, which inhibits the adult male spongy moth’s ability to locate females. This 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, and no adverse effects have been reported in the two decades that this pheromone has been used for spongy moth control.

“These treatments are highly effective at reducing the mating success of this insect. The chemical signal released is specific to spongy moth and will not interfere with the life cycle of other insects,” said Christopher Foelker, DATCP Spongy Moth Program Manager.

The following counties are scheduled to receive treatment: Barron, Bayfield, Buffalo, Burnett, Chippewa, Dunn, Grant, Eau Claire, Lafayette, Pepin, Rusk, Sawyer, Trempealeau, Vernon and Washburn.

Spongy moths are non-native pests that defoliate many tree species during their caterpillar stage, causing tree stress and potentially tree death. The harmful effects of spongy moths include the cost of removing dead trees and potential loss of property value. Caterpillars also shed their skin several times as they feed, and these bristly skins can irritate the eyes, skin, and respiratory system in humans.  

Treatments are expected to begin in late June in southwestern Wisconsin and end in mid-July in northwestern Wisconsin. Maps of specific treatment areas are available online at https://smaerialspray.wi.gov.

To receive up-to-date information on treatment plans:


Note: A new common name for Lymantria dispar, spongy moth, replaced the prior name of this insect, gypsy moth, in 2022. Thank you for your patience and understanding as we transition through the name change process. For more information, visit the Entomological Society of America website.