Evaluation of Bacillus sphaericus against Mansonia dyari larvae in phosphate lakes in Polk County, Florida.

Effective Mansonia larval control is difficult to achieve in Polk County, Florida, because the larvae attach to the root and stem mass of water lettuce (Pistia stratiotes) and water hyacinth (Eichhornia crassipes). This study evaluated 2 Bacillus sphaericus larvicides as possible control products in 3 phosphate lakes in 2 areas maintained by Polk County Mosquito Control. VectoLex WDG was applied at 56 kg/km2 and 170 kg/km2 and VectoLex CG at 560 kg/km2 and 1,100 kg/km2.