Parasitic nematodes seek out insects harmful to garden plants, shrubs and trees in their soil-borne stages and destroy them from the inside out. Present in soils throughout the world, these microscopic, non-segmented worms destroy over 200 types of insects that mature in the ground, including weevils, Japanese beetles, fleas, borers and fungus gnats, before they reach adult stages.

When released into the soil, Steinernema feltiae seek out the larvae and pupae of susceptible pests by sensing the heat and carbon dioxide they generate. They enter pests through various orifices or directly through the “skin.” Once inside the host, they release a bacterium that kills it within a day or two. They will continue to feed on the remains, multiplying as they do, before exhausting it and leaving to seek another food source.

Nematodes do not prey on lady bugs, earthworms or most other beneficial insects. They are harmless to plants and humans as is the bacterium they produce. Evidence of the nematodes effectiveness, other than reduced pest populations, is difficult to spot as these microscopic creatures consume their hosts in the soil, leaving little trace behind. They’re appropriate for use on lawns, in gardens and around trees and shrubs. They need generally moist condition to facilitate their movement.