Monterey Garden Insect Spray is a broad spectrum insecticide that contains Spinosad , which is derived through fermentation of a naturally-occurring soil bacterium. Spinosad works on the insects' nervous system, causing paralysis and death in 1-2 days. Since the insects are paralyzed, they may stay on the plants and be mistaken for live insects; always check 2-3 days after spraying to evaluate control in the insect population. For control of foliage feeding worms/caterpillars, thrips, fire ants and many other listed pests.