They are attracted by coreopsis, candytuft, morninglory, and nemophila. Larvae have a voracious appetite for aphids, scale, thrips, mealybugs, and leafhoppers. Tachinid flies - Adults resemble houseflies, but are larger, and are covered with bristles. They parasitize adults and larvae of beetles, grasshoppers, and caterpillars such as sawflies, armyworms, and gypsy moth. Trichogrammatid wasps - Very minute wasps that parasitize insect eggs.
Some species are host and habitat specific.
Timing of release is critical since these parasitic wasps only attack the egg stage of insect pests. Paper wasps, Hornets - Though more often considered pests, paper wasps consume many caterpillars while raising their young during the summer months. Hornets catch many soft bodied flying insects to feed their larvae.