Scott Hartman, Deputy County Administrator, joined the committee for the report.
He noted that moth season was approaching, and the committee, citizen scientists, and the public were asked to watch for spongy moth egg masses. He mentioned sending a message with more details to the citizen scientists, which the committee was copied on. There was also an article in MC Thrive on identifying and removing egg masses.
Removing egg masses now could prevent hundreds or thousands of moths from hatching and defoliating trees. Hatching typically occurred from late April to May, and the caterpillars grew rapidly, feeding on over 300 tree species, mainly oaks and hardwoods. Removing egg masses early not only prevented damage but helped curb the breeding cycle. A video on safe removal was included in their outreach materials.
For the past two years, McHenry County had been in a spongy moth outbreak, starting after residents raised concerns with the County Board. The Board took action, and Mr. Hartman became involved in the response.
McHenry County was now considered “infested,” meaning eradication wasn’t feasible, and efforts shifted to slowing the spread. Historically, these outbreaks followed a pattern of population explosions followed by natural crashes, as seen in McHenry County from 2009 to 2011. They hoped the same would happen after the recent outbreaks.
Over the past two years, they had monitored moth populations through trapping. Trapping didn’t reduce the population but helped collect data, which identified hotspot areas. Looking ahead to 2025, they planned to continue trapping, work with trained citizen scientists, and compare 2024 and 2025 data.
They were hopeful for two natural population controls: a population crash and the resurgence of a soil fungus, Entomophaga maimaiga, which was lethal to moth caterpillars and thrived in warm, wet springs.
Mr. Hartman explained that if state support was limited, they might need to purchase additional lures and insecticide strips at a cost of $500–$700, noting that many traps were reusable, helping keep costs low.
He recalled property owners in Bull Valley and Marengo raised concerns about tree loss and defoliation, leading to discussions about whether public dollars should be used for mitigation on private property. The County Board decided to respond with monitoring and data collection rather than direct intervention.
This approach, Mr. Hartman said, demonstrated responsive government. The county listened, engaged, and continued monitoring despite disagreements on spraying.
He recommended continuing the low-cost, high-value trapping and monitoring program in 2025 to collect critical data, assess population decline, and guide future decisions.