Insects that Sevin dust kills include potato beetles, parasitic wasps, ladybugs, bees, roaches and fleas. Sevin dust contains a chemical called carbaryl, which kills over 100 types of insects.
Sevin dust works by degrading an insect's nervous system through ingestion or direct contact. There are different variations of Sevin dust, including 5-percent carbaryl dust, 10-percent carbaryl dust and garden dust. Sevin-5 is reserved for outdoor use on garden lawns, and it kills 65 different pests, including Japanese beetles, grubs and ticks.
Sevin dust can be applied in powder form or mixed with water for spraying on crops, such as tomato plants. Sevin dust is normally applied on fruits and vegetables, but the crops must be washed with water before these foods are consumed. However, there are times when spraying around the plant is necessary. For instance, 2 tablespoons of 50-percent Sevin powder with 1 gallon of water is for application on weed-infested areas around tomato plants, which are havens in which stink bugs thrive. The solution should not be sprayed directly on the tomato plants, and Sevin dust must never be applied on flowering plants to avoid killing honeybees.
The liquid form of Sevin dust kills insects like Colorado potato beetles. Liquid Sevin dust works best on plants that reach up to waist or chest level. Adding water to liquid Sevin dust is still necessary for thorough application of an area.