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Treatment Scheduled for Black Fly Control on Potomac River

HAGERSTOWN, MD (August 19, 2019) – Washington County Government would like to notify all citizens that the Maryland Department of Agriculture, in partnership with the Department of Natural Resources, will treat targeted areas of the Potomac River in Washington County as an ongoing effort to control the black fly population. Treatment is scheduled for Tuesday, August 20, 2019 beginning at 8:30 a.m.

The department will apply a Bacillus thuringiensis israelensis (Bti)-based larvicide via helicopter (Bell 206 Long Ranger, green and white paint scheme. Tail number N641HA). Bti is a naturally occurring bacteria found in soils worldwide. It is a bacterial insecticide, not a chemical, and is only harmful to a very limited variety of organisms including midge, black fly, mosquito larvae and a few other aquatic Dipteran (flies) insects.

The treatment may cause temporary discoloration of the water, but it is completely non-toxic and is not harmful to humans, fish, crabs, or other aquatic invertebrates.

For additional information, please contact Washington County’s Public Relations and Marketing Department at 240-313-2380.

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