2020 Gypsy Moth Spray
Notice of Spring Treatment and Public Hearings
We sent three letters to property owners impacted by the 2020 Gypsy Moth Suppression Program. The first two informed property owners of the public hearings associated with the program. The final letter explained more about the program's purpose and how it works.
The first public hearings for the 2020 Gypsy Moth Suppression Program Special Assessment was held on April 20, 2020 City Council meeting. During the meeting, the City Council held public hearings to take public comments from interested persons affected by the proposed project. We sent the notices linked below to all the impacted property owners describing the process and how to provide public comment.
The second public hearings for the 2020 Gypsy Moth Suppression Program Special Assessment was held at the May 4, 2020 City Council meeting. During the meeting, the City Council held public hearings to take public comments from interested persons affected by the proposed project. We sent the notices linked below to all the impacted property owners describing the process and how to provide public comment.
2020 Spring Treatment
05/31/2020 Update: Our consultant has identified June 1 as the day for treatment. Helicopters will be in the area in the morning tomorrow.
We partner with Hamilton Helicopters, Inc. to perform gypsy moth treatments in mid-May to early June. The exact date is determined through continued monitoring of weather conditions, as well as caterpillar and tree canopy development. Spraying will be done when average wind speed is less than 10 miles per hour and relative humidity is more than 50-percent. In most cases, these constraints limit spraying to a morning activity.
2020 Treatment Locations
Using resident complaints, tree damage assessments and egg mass surveys, our consultant, Aquatic Consulting Services, LLC, determined the areas of treatment. A total of 575 acres are scheduled for treatment this year. You can find treatment locations on the Aerial Spray Map 2020 Map (PDF) or use the Interactive, Searchable Gypsy moth Map.
Property Owner Cost
If a property you own is within a treatment location, a fee is assessed on your 2020 Summer Property Tax Bill.
- $26 for small parcels with equal to or less than .5 acres
- $82 per treated acre for parcels larger than .5 acres
How It Works
The insecticide used in this process is a naturally occurring bacteria called Bacillus thuringiensis (Bt), which is also used by organic gardeners. The applicator is Hamilton Helicopter, Inc., PO Box 264, 4488 134th Avenue, Hamilton, Michigan, 49419, (616)291-5808. The Bt brand used is Foray 76B (or equivalent). On treatment days, our contractor will apply 1 quart of the Bt material over each acre in a very fine mist. It’s unlikely for people to see or feel it. Drying takes 4 - 6 hours and once dry, rain does not wash it away.
The Bt only affects the caterpillars of moths and butterflies that are actively feeding at the time of treatment, which is why the application date varies. In an effective spray application, you may notice a change in the level of activity and responsiveness of the caterpillars, and they will die in 5-7 days.