For up to 180 days of residual control, FourStar® Microbial Briquets feature naturally occurring active ingredients Bti and Bsph. The solution can be applied to standing water without fear of harming aquatic life as well as in areas frequented by humans, livestock and wildlife. Developed with dual-action sustained release technology, apply FourStar® Microbial Briquets to potential mosquito breeding areas prior to flooding as periodic wetting and drying of the treatment site will not reduce their effectiveness.