Great information from St. Clair County Spongy (formerly Gypsy) Moth Program, A cooperative program between the County of St. Clair and Friends of the St. Clair River.
Strategies for landowners to manage Spongy Moth
● To avoid harming Michigan native species, please confirm what you are seeing is a Spongy Moth, an invasive
species. The Spongy Moth Lifecycle information on the back of this sheet will help you identify gypsy moth
● Avoid damaging tree bark, which can leave the trees vulnerable to other pests and disease
January - April:
Remove and destroy egg masses prior to hatch. Every egg mass you destroy prevents 100 to 1,000
caterpillars from hatching.
● Search for Spongy moth egg masses on trees, firewood, outdoor furniture, siding, and other outdoor surfaces
● Scrape egg masses into a container of soapy water and let sit overnight, or burn or bury the egg masses
● Any eggs that fall to the ground or get left behind can still hatch
March - April:
Spray egg masses with biologic oil once temperatures are above 45 degrees.
● Biologic Golden Pest Oil: https://www3.epa.gov/.../ppls/057538-00011-20040309.pdf
● Make your own spray with soybean oil and water. See directions in the Homeowner’s Guide to Spongy Moth
Management from West Virginia University Extension, page 11: https://bit.ly/manageLDD
March - June:
Wrap trees with sticky barrier bands to trap caterpillars as they move up and
down the trunks.
Follow precautions in the article to protect your trees from damage
https://fyi.extension.wisc.edu/.../making-a-sticky.../
Wrap trees with folded burlap barrier bands to trap the caterpillars.
https://youtu.be/9h6e5ZyLdKQ
May - August:
Manage Spongy moth caterpillar, pupa, and moth populations.
● Drop caterpillars into a bucket of soapy water and let sit for 48 hours. Caution! Their hairs can be irritating. Use a brush or
wear gloves when handling gypsy moth caterpillars.
● Spray caterpillars and moths directly with a strong mixture of dish soap and water. (Caution: can make surfaces slippery.)
● Monitor and maintain barrier bands.
In hot, dry weather, water prized trees defoliated by Spongy moth.
● Run a sprinkler for about an hour in the morning, soaking the ground under the spread of the branches
https://extension.umn.edu/.../watering-established-trees...
September - December:
Leave egg masses in place. Do not remove them until January to allow the Spongy Moth Field Staff to complete its survey of gypsy moth egg masses to determine next spring’s spray map.
Report Spongy moth on your St. Clair County property: www.stclaircounty.org/Caterpillars/CaterpillarsSurvey.aspx
MSU Extension Integrated Pest Management for Spongy Moth: canr.msu.edu/ipm/invasive_species/gypsy-moth/
Friends of the St. Clair River Contact Information: www.scriver.org ∙ gypsymoth@stclaircounty.org ∙ 810-294-4965 (LINK)
Original source an be found here.
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