Spongy Moth
Spongy moth has been a forest pest in Michigan for over 40 years. Over the last several years, the population and effects of spongy moth have been above average in Grand Rapids. This has mainly affected areas with high oak tree populations.
How You Can Help
If you encounter a tree affected by spongy moth, there are a few things you can do to help.
- Read the Homeowners Guide to Spongy Moth Management(PDF, 1MB) tip sheet
- Water the tree(s) throughout the summer to help with leaf regrowth
- Remove egg masses and wrap trees with a barrier
- Treat the tree(s) with an insecticide like B.t. caterpillar and webworm control
- Contact a local forester for treatment options. Foresters can be found at the International Society of Arborculture's website
- Report sightings of spongy moth to 311
Learn how to remove egg masses
October through late April, look for egg masses on tree trunks and scrape them into a cup of soapy water using a plastic putty knife or other dull scraping tool. Egg masses are light brown, sponge-like in appearance and about the size of a quarter.
