The East Middlesex Mosquito Control Project will be conducting a helicopter application of the biological larvicide, Bti (Bacillus thuringiensis var. israelensis), to control mosquito larvae. Wetlands currently being evaluated for this application are located near Davis Rd./Winterberry Way, Old Stagecoach Rd, and at Hartwell Town Forest. One helicopter application will take place between April 22, 2025 and May 2, 2025. The Bti will be applied in a granular formulation by a helicopter flying low directly over the wetlands. Residents do not need to take any special precautions for this application.

Bti is a natural occurring bacterium found in soil, and is classified by the EPA as relatively non-toxic. Bti is target specific and only affects mosquito larvae and a few closely related aquatic insects in the fly family. Bti breaks down quickly in the environment. The product to be used is VectoBac GS (EPA Registration #73049-10).

For further information, contact the East Middlesex Mosquito Control Project at 

781-899-5730.