Parts of Livingston County, McLean’s northeast neighbor, have been scheduled for spraying this past week along with six other counties in northern Illinois for the gypsy moth, leaving the rest of us wondering will we be next.
Gypsy moth caterpillars eat the leaves of hundreds of different species of trees, leaving behind winter bare trees. The infected trees have a chance of dying from repeat defoliations or becoming stressed enough to possibly succumb to other diseases or insect infestations.
Vast swaths of forestland in the northeast can be completely defoliated in heavy years. The residents in these areas can actually hear the caterpillars chomping on their favorite trees. The U.S. Forest Service considers the gypsy moth the most devastating tree pest.
Scott Shirmer, northern field operation manager for Illinois Department of Agriculture, has high hopes for combating this pest with Organic Splat-O, a mating disrupter that will be dispersed over numerous acres inundating the air with the scent of the female.
The male is unable to find a female and mate. Scott says it is perfect timing because the caterpillars are almost ready to pupate. Pupation can last 14 to 21 days before adults emerge, mate and lay egg masses on the trunk of trees. These egg masses overwinter and caterpillars emerge the following spring.
An insect with such a broad host range can be worrisome, but Scott is optimistic. He explains, “gypsy moths are not like Emerald ash borer in that they seek mates rather than look for food. Emerald ash borers infest, kill and move on. Gypsy moths form more of a pocket infestation vs. a wide spread blanket therefore making control plausible."
Scott says there are probably 10,000 gypsy moth traps throughout the state of Illinois. A computer uses historical data to determine if treatment is needed and this year a bloom occurred in Fairbury, Streator and Pontiac resulting in a scheduled aerial treatment of thousands of acres to combat the invasive insect.
He does not want to cause alarm for other counties, but does want us to be on the lookout. If gypsy moth is suspected, USDA may come out to inspect or set up a trap. Homeowners in the infected areas are encouraged to look for the brown fuzzy egg masses that can be on the trunk of trees, lawn furniture, vehicles and houses. Egg masses should be scraped into a plastic bag, sealed and thrown away.
For more information on life cycle or identification of gypsy moth, visit https://extension.illinois.edu/gypsymoth/ for more information.