One application of Flea Destroyer contains 10 million microscopic, beneficial nematodes (Steinernema feltiae and Steinernema carpocapsae) that naturally live in soil, bark and ground litter. The nematodes travel through the soil, penetrate the flea larvae that develop there, and release bacteria that kill the larvae. They reproduce inside of the flea larvae, increasing their population by 1000x with every flea killed, meaning that Flea Destroyer only needs to be applied once a year. By ending the flea life cycle before fleas can migrate to pets and homes, Flea Destroyer helps effectively end recurring flea problems naturally, without chemical pesticides.