IDOA Concludes Gypsy Moth Treatment In Select Nothern Illinois Counties

May 27, 2019

An adult male gypsy mot. Females have a white hue.
Credit Wikimedia Commons

The Illinois Department of Agriculture recently treated several northern Illinois counties for gypsy moths.

Areas in northern Will County, Joliet/Will County, and Jo Daviess County were treated with BtK. This bacteria is an alternative to chemical pesticides and was applied in two stages by helicopter over the month of May. Scott Schirmer is the northern Illinois field office section manager for the Department of Agriculture. He says the bacteria is specifically formulated to attack gypsy moths, while leaving beneficial bugs like dragonflies and bees alone.

“As they consume the leaves and the product is on the leaves, their digestive system activates the product, and the toxin kind of, for lack of a better term, gives them a stomachache, stops them from feeding, and they effectively starve,” he said. 

The gypsy moth is an invasive species that feeds on more than 250 species of trees and shrubs, and has a particular appetite for oak trees. Large groups of the moth can defoliate trees and strip plants bare. This leaves them vulnerable to diseas and other insects, or kills them outright.  Counties with heavy infestations of gypsy moths, including Will County, are quarantined. This requires state officials to inspect nursery stock, firewood, and outdoor equipment leaving the county for cases of contamination.

“The peanut-buttery, putty looking stuff. Those are their egg masses and that’s basically what we inspect for. That would be pretty visible year round, whereas this time of year, you’re looking for tiny caterpillars or during the flight season, the male moths are going to be flying around trying to mate," Schirmer said.

The Department of Agriculture advises anyone who finds a gypsy moth to call them at 1-866-296-MOTH (6684). That way, the Department can take measures to slow the spread of the bug's population.