Bay County Building
515 Center Avenue
Bay City, Michigan 48708-5941

Aerial Gypsy Moth Treatment will be done between May 24–June 5, 2020

The Bay County Gypsy Moth Suppression Program will conduct Aerial Gypsy Moth Treatment in the next few weeks at a heavily infested 381 acre woodlot in Gibson Township in northern Bay County. Monitoring surveys show that the Gypsy Moth population in that area has reached outbreak levels, and is likely to damage the trees in the area. This population may also spread to other areas of the county if not treated.

Bay County residents may notice a low-flying, yellow fixed-wing aircraft over wooded areas between 6:30 a.m. to 10 a.m. on the day of treatment operations. The aircraft will be spraying Foray 48B, a naturally-occurring forest health product that contains the soil bacterium Bacillus thuringiensis kurstaki (BT) that specifically affects Gypsy Moths caterpillars that are feeding at the time of treatment. BT has no known impact to non-target organisms such as humans, pets, birds, fish, and other insects. Field monitoring is performed afterwards to ensure that there are no adverse impacts. The product is an OMRI Certified organic, water-based, liquid formulation of BT that is applied to the forest canopy at a rate of ½ gallon per acre.

Timing of the aerial campaign is extremely important, weather dependent, and is based on caterpillar development and leaf development on the trees to be sprayed. The Gypsy Moth Caterpillars started hatching on May 11th and regular surveillance of the Gypsy Moth population will determine the exact date of treatment. It is anticipated that aerial treatment for Gypsy Moth will take place between May 24 – June 5, 2020.

The Gypsy Moth Suppression Program has implemented a Pandemic Preparedness Plan which includes protective equipment, extra sanitation procedures and social distancing expectations in order to protect the health and safety of staff and the public during this treatment activity.

For more information contact Program Coordinator Alicia Wallace at (989-895-4195). The Bay County Gypsy Moth Suppression Program is a division of the Bay County Environmental Affairs and Community Development Department.