Aphidius can parasitize about 40 aphid species, primarily the green peach aphid and closely related species. This species occurs naturally outdoors and frequently parasitizes aphids in green houses. Aphidius is a good searcher, and can locate new aphid colonies when aphid populations are low.

Aphidius is a small parasitic wasp, native to North America. About 100 eggs are laid in aphids which the larvae subsequently develop. At 77 degrees F, 10 days are required from egg to adult for Aphidius. At 70 degrees F, two weeks are required fro development on the parasite. Up to 200-300 aphids are attacked be each female. Fertilized eggs develop into females, nonfertilized eggs develop into males. There are usually twice as many females as males.

Aphidius is shipped as parasitized aphid mummies from which adults will emerge, or as newly emerged adults. Apply 500 to 3,000 Aphidius per acre, 2 to 3 times, one week apart.