Beneficial Insect — Green Lacewings

Common Name: Green Lacewing

Genus Species: Chrysoperia rufilabris

While there are dozens of beneficial insect predators, most have limited applications, one really stands out as having a multitude of applications – Green Lacewings.

Controlling insects biologically is challenging because it requires certain detailed knowledge of the target pest, frequent monitoring of the pest populations and anticipatory strategies. That sort of control usually means the application of agricultural chemicals.

To rely on biological controls alone one must think ahead. One must recognize and anticipate a threatening pest population buildup. Plants can tolerate some pests and the economic threshold should be a consideration. In other words, the dollar gain should exceed the dollar cost.

  Description:

Lacewings in this group are nearly always green in body and wing color. Adult lacewings have lacy wings and they look transparent. Their wings have short hairs along the edges and veins. They have long, filiform antennae, and chewing mouthparts. Lacewing larvae have elongated and flattened bodies that resemble tiny alligators.

  Diet:

Lacewing larvae feed on other soft-bodied insects or arachnids, including aphids, mealybugs, mites, and Lepidoptera eggs. As adults, lacewings may consume a more varied diet.

  Life Cycle:

Lacewings undergo complete metamorphosis, with four life stages: egg, larva, pupa, and adult. The life cycle varies in length according to species and environmental conditions. Most adults will live for 4-6 months. Generally, the larval stage may last several weeks, and usually requires three instars. Pupae may develop into adults in the safety of a silken cocoon attached to the underside of a leaf or on a stem, but some species pupate without a case. Common lacewings may overwinter as larvae, pupae, or adults, depending on the species.

  Benefits:

 Huge appetite for aphids
 Wide range of other pests attached
 Several generations each season

  Limitations:

 Only the larva stage is a predator
 Ants can interfere with their attacks on aphids

  Purchasing Lacewings

Green Lacewing eggs and
larvae hanging under a leaf.

Green lacewing eggs have been available from a biological control supply houses and even Amazon.com. These have been used with success in controlling aphids in greenhouses and in plant beds. One advantage when using lacewing eggs over lady beetles is that the beetles are winged and will disperse from the release area. When the lacewing larvae hatch, they are wingless and remain in the general area to search for insect prey.

  The use of some products may not be legal in your state or country. Please check with your local county agent or regulatory official before using any pesticide mentioned in this publication.

  How To Release Green Lacewings:

Lacewings are the best all-purpose predator for your garden or greenhouse. Lacewings stay where the eggs are placed in the garden and the larvae are voracious feeders. About 10 of these Chrysoperla rufilabris lacewing eggs per plant or 1,000 eggs per 200 sq. ft. will control a moderate aphid population.

For best results, release Green Lacewing early in the season when pest numbers are low. Make a minimum of 3 releases. In gardens and greenhouses, release eggs at approximately 1,000 eggs per 2,000 sq. ft. For farms release 5,000 to 50,000 per acre depending upon infestation.