Mosquito Science Mosquito Killer 30 oz volume. Naturally-based, safe, biodegradable. Dual action - kills mosquito larva in water, repels adult mosquitoes for up to 8 weeks. Use early in the season and use follow-up allications as directed for the full season, until outdoor daytime temperatures fall below 55° F. Effective control that biodegrades without persistent toxic chemicals, bacterial toxins or insect hormones. Recommended Application for Mosquito Larvicide: Use in and around mosquito-bearing still waters, including ponds, ditches, water impoundment, marshes, swamps, puddles and artificial water sources such as birdbaths, tires, tree-holes, gutters, cans or debris. Also for use in areas subject to tidal water, seepage, overflow, flooding, snowmelt or rainwater. Recommended Application for Mosquito Repellent: Use in yards, parks, playgrounds, schools, golf courses, and other areas where mosquitoes may congregate. Apply to grass areas, gardens, mulched areas and under trees and shrubs.