Font size with jQuery A+ | A-

What are Larvicides and What Do They Do?

Larvicides are both chemical and biological products applied to water that either kill or inhibit the development of immature mosquitoes. Larviciding is an integral part of our mosquito control program. Our staff spends much of each day looking for and treating mosquito breeding areas throughout the county. Mosquitoes are easiest to control in the earlier stages of their life because they remain in water until they become adults. These EPA registered larvicides are applied by licensed and trained staff to areas of water where the mosquitoes are growing. We are able to eliminate great numbers of mosquitoes before they become flying adults by using the appropriate larvicides. Franklin County Public Health makes it a priority to use the most effective larvicides with the least environmental impact.

Catch Basin/Storm Drain Treatment

As part of our commitment to mosquito control, each spring our staff implements a comprehensive catch basin (storm drain) treatment program throughout the county. We inspect catch basins and use historical data and mapping to determine whether or not it is designed to hold water or is holding water. Once identified, these “true” catch basins are monitored throughout the season. If sampling indicates that there are eggs, larva or pupa present, these catch basins are treated with the appropriate larvicides to kill and/or prevent the mosquitoes from hatching into adults. These treated catch basins are also monitored to ensure that the larvicides are working. If necessary, the catch basin will be treated again.

A Complete List of Larvicides We Use:

AGNIQUE MMG (EPA Reg. No. 53263-28)

AGNIQUE® MMF is a larvicide and pupicide with a unique physical mode of action rather than chemical toxicity. It is ideally suited for mosquito control programs as it can be used in a wide range of habitats from fresh water to salt water and it's even labeled for use in potable water.
Product Label | MSDS

ALTOSID XR 150 (EPA Reg. No. 2724-421)

ALTOSID® is a larvicide that disrupts the normal growth pattern of immature mosquitoes in water and prevents them from becoming breeding, biting adults. ALTOSID is an easy to use, long-term, cost-effective and environmentally responsible mosquito control larvicide.
Product Label | MSDS


AQUABAC is a biological larvicide used to control mosquito larvae and black fly larve in aquatic habitats. AQUABAC is based on the naturally occurring soil bacteria, Bacillus thuringiensis israelensis (Bti). This highly effective and economical microbial insecticide can be used in nearly all aquatic habitats, to effectively and efficiently control target species in the larval stage.
Product Label | MSDS


FOURSTARTM BRIQUETS are a highly selective microbial insecticide effective against mosquito larvae in a variety of habitats for up to 45/90/180 days or more. FOURSTAR BRIQUETS release effective levels of Bacillus sphaericus and Bacillus thuringiensis subspecies israelensis to the water surface over time as the briquet dissolves.
Product Label | MSDS


SPHERATAX SPH 50G is a highly selective microbial larvicide granule containing the bacterium, Bacillus sphaericus. Bacillus sphaericus is a naturally occurring bacterium that is found throughout the world and effectively kills mosquito larvae present in water.
Product Label | MSDS


VECTOLEX® is a biological larvicide providing selective, environmentally sound control of most mosquito larvae. VECTOLEX is based on Bacillus sphaericus a naturally occurring bacturim in the environment. These fast-acting products are commonly used in municipal and industrial water treatment facilities, animal waste lagoons, storm sewer catch basins, continuously irrigated croplands and pasture, and mosquito breeding sites. VECTOLEX offers effective residual control of a number of mosquito species.
Product Label | MSDS


VECTOMAXTM is a unique biological larvicide that combines Bti andBacillus sphaericus in one homogenous formulation. These two bacteria are combined in one molecule which ensures that larvae feed on both at the same time. VECTOMAX offers the faster, broad spectrum control of VectoBac® (Bti), with the residual control of VectoLex® (B. sphaericus).
Product Label | MSDS