Abstract: Larvicide products are widely used in vector control operations to target the immature stages of mosquitoes. However, aquatic mosquito habitats often include cryptic sources such as: septic tanks, planters, storm drains, and yard drains. These locations can be challenging to treat; therefore, effective and efficient treatment methods are essential. Natular DT (Clarke, IL.) is a compact bi-layer tablet with spinosad (Saccharopolyspora spinose) as an active ingredient. This product can be used in containerized and cryptic water sources to prevent mosquito development and emergence. The first effervescent dose provides control within the first 24hr and the second dosage dissolves at a slower rate, providing continuous control for up to 60 days. At the Sacramento-Yolo Mosquito and Vector Control District (SYMVCD), we tested the efficacy of Natular DT in an artificial yard drain system that resembled a typical suburban drain system. Larval mortality was assessed weekly and we found that the point of product application (inlet, outlet) affects the overall larval mortality dynamics, and that application in a single drain has cascading mortality effects in the rest of the interconnected drains. Our results suggest that Natular DT can be used as an effective control tool by SYMVCD as well as other abatement programs.
