Document Type

Weed and Insect Management


The Agricultural Extension Service receives numerous inquiries for information about where insect predators and parasitoids can be purchased. These insects are intended for use by both homeowners and commercial growers as biological control agents.

Biological control uses beneficial organisms rather than insecticides to reduce insect populations. Almost all insect groups include some benefi cial members. The use of beneficial organisms is particularly important where chemical residues are undesirable. Beneficial organisms can be predators, such as ladybugs, lacewings and praying mantids that feed on other insects. Others, such as some species of nematodes and wasps, including Trichogramma, are parasitoids with an immature stage that lives on or inside a host, which the parasitoid eventually kills. Trichogramma wasps lay their eggs into the eggs of caterpillars, where they develop by feeding inside the host’s egg. An example of a beneficial pathogen is Bacillus thuringiensis, which is used as a microbial insecticide.

The Tennessee Department of Agriculture does not list the decollate snail, Rumina decollata, as a biological control organism suitable to be brought into Tennessee.

The Agricultural Extension Service is not in the business of advertising, selling or buying benefi cial organisms. This list of sources was compiled as a response to public requests for information. This listing and general description of benefi cial organisms are not recommendations and do not imply effectiveness in controlling any pest.

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