Spongy Moths Program

2022 Spongy Moth Spray

Notice of Spring Treatment and Public Hearings 

In response to resident requests, the City of Wyoming has a long-standing practice of providing spongy moth monitoring and a spring treatment as needed.  Information and updates will be available here throughout the process.

March 28, 2022 UPDATE:  The first mailing has now been sent to property owners impacted by the 2022 spongy moth spray program. The first letter contained information about public hearings associated with the program. 

The first public hearing of the proposed 2022 spongy moth spray will be held on April 4, 2022, as part of the regular City Council meeting.  During this meeting, the City Council will take public comment from interested persons affected by the proposed project.  The notices linked below have been mailed to all property owners in the treatment area, describing the process and how to provide public comment. 

2022 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 1544 acres are scheduled for treatment this year. You can find treatment locations on the Aerial Spray Map 2022 (PDF) or use the Interactive, Searchable Spongy Moth Map.

Property Owner Cost

If a property you own is within a treatment location, a fee is assessed on your 2022 Summer property tax bill.  The fees will be as follows:

  • $27 for small parcels or treatment areas equal to or less than .5 acres
  • $72 per treated acre for parcels with treatment areas larger than .5 acres

How It Works

In addition to working with Aquatic Consulting Services, we partner with Hamilton Helicopters, Inc. to perform spongy moth treatment in late-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, this limits spraying to a morning activity.

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 Helicopters is the applicant and 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 is unlikely for people to see or feel it. Application generally takes 4 - 6 hours (for the entire city) and the product dries within minutes.

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. 

Learn More About the Program

Spongy Moths Suppression Program

Residents and property owners can use several techniques to help suppress this pest. Below is a collection of documents that are useful in understanding the spongy moth, its treatment, and the techniques you as residents and property owners can use to minimize this pest on your property. 

Updates and More Information

We'll post additional details about the treatments on Facebook and Twitter and update this page. Have questions about the City of Wyoming Spongy Moth Suppression Program? Contact us at the City Clerk's Office by calling 616-530-7296 or completing our Spongy Moth Reports and Inquiries Form below.  

Spongy Moth Reports and Inquiries

Use this form to report spongy moths in your home or neighborhood, or to inquire as to the status of spongy moth suppression efforts.

* Required