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Mosquito Control Project
Norfolk County Mosquito Control
The Norfolk County Mosquito Control Project treats wetlands in 24 of the communities of the District,  including the Town of Needham, with a granular form of Bti (Bacillus thuringiensis israelensis), a naturally occurring soil bacterium that kills mosquito larvae before they become mosquitoes.

Bti is virtually non-toxic to humans, plants and animals. The Bti is impregnated on coarsely ground corncob granules. In the larger wetlands inaccessible from roads, these applications are done by helicopters flying at tree-top level. The granules, when applied, fall straight into the wetland and do not drift beyond the targeted area.

According to information on the EPA website, microbial larvicides "are essentially nontoxic to humans, so there are no concerns for human health effects with Bti" and "do not pose risks to wildlife, most non-target species, or the environment." 

The mosquito species that are most likely to be potential vectors of West Nile Virus breed in containers like rain gutters, kiddie pools, or any other containers that hold water for more than five days. The public can play a major role in controlling these vectors by eliminating all standing water on the property.

Additional information on larvicides (including detailed information on toxicity), mosquito breeding, and the aerial program may be found on the Norfolk County Mosquito Control Project’s website. You can also contact the Health Department at (781) 455-7523.