The common green lacewing (Chrysoperla rufilabris) is a widely used beneficial insect which naturally controls many different pests. Actually, most species of the adult lacewing do not kill other insects but subsist on pollen, sweet nectar, etc. It is their offspring or lacewing larvae that do the job. The adult lacewing lays her eggs on the foliage, each on top of hair-like filaments. After a few days the eggs hatch and a tiny larva emerges which is also known as the “aphid lion” because of its voracious appetite.
Lacewing larvae are similar in appearance to an alligator with pincers like tiny ice tongs, and vigorously attacks its prey, injecting a paralyzing venom then drawing out the body fluids of its victim. Besides aphids, they feed on just about any soft-bodied pest they can “grab,” including citrus mealybugs, cottony cushion scale, spider mites, thrips, caterpillars, insect eggs, etc. It is known to be cannibalistic if no other food source is available. During the two to three weeks in this stage it will devour up to 200 victims a week. After this, it will pupate by spinning a cocoon with silken thread and approximately five days later the adult emerges to complete the life cycle. There are five or six overlapping generations each season.
Release rates depend on a number of factors such as severity of pest problem, number and size of plants, number of beneficial insects already present, etc. A general guideline would be: 1,000 eggs per 2,500 square feet (50 x 50 foot area). Since the larvae feed for about two weeks, a second release, two weeks later, might be necessary.
Lacewing eggs are shipped in a carrier of rice hulls. They should be released as close as possible to pest infested areas.
Tip: Ants feed on the honeydew that sucking insects (aphids, mealybugs, thrips) produce and will vigorously protect these pests from their natural enemies. If possible, control ants prior to release.
• Lacewings – University of Kentucky Department of Entomology
• Life History of Chrysoperla rufilabris (PDF format) – USDA
• Natural Enemies Gallery – University of California IPM Program
• The Aphid Lion – Pesticide Action Network Germany