- Green lacewing adults are green or brown, about 0.5 – 0.75 inches (1-2 cm) long. They have transparent, finely veined wings that are longer than their body. Adults are active at night and feed only on pollen and nectar, which they need in order to lay eggs. Larvae are spindle-shaped with pincher-like mouth-parts. Lacewing larvae are often referred to as alligators due to similarities in appearance.
- Lacewing larvae voraciously attack their prey by seizing them with large, sucking jaws and inject paralyzing venom. The hollow jaws then draw out the body fluids of the pest. Of all available commercial predators, this lacewing is the most voracious and has the greatest versatility for pests of field crops, orchards, and greenhouses.
- The adult lacewing lays her eggs on foliage. Each adult female may deposit more than 200 eggs. Each egg is attached to the top of a hair-like filament. After a few days the eggs hatch and a tiny predatory larva emerges ready to eat the pests. Each lacewing larva will devour 200 or more pests or pest eggs a week during their two to three week developmental period. After this stage, the larvae pupate by spinning a cocoon with silken thread. Approximately five days, later adult lacewings emerge to mate and repeat the life cycle. Depending on climatic conditions, the adult will live about four to six weeks. Lacewing adults can survive the winter in protected places but have a difficult time surviving cold winters.
Larvae Rate: Moderate: 0.4-0.8 per sqft biweekly or as needed, High: 1 per sqft biweekly
Adult rate: divide larvae rate by four
Egg rate: multiply larvae rate by five.
Many species of adult lacewings do not kill pest insects; they actually subsist on foods such as nectar, pollen and honeydew. It is their predacious offspring that get the job done. In general, they attack the eggs and the immature stages of most soft-bodied pests. Lacewing larvae are also known as aphid lions. They are tiny upon emerging from the egg, but grow to 3/8 of an inch long.
If release is not possible nearly immediately upon arrival of the lacewing eggs, because of weather conditions, for example, the eggs can be stored at no lower than 50°F (10°C) for up to 48 hours. To minimize egg mortality, humidity should be approximately 75%. Warmer temperatures will speed up larval emergence, but the eggs should not be held at more than 80°F (26°C).
When targeting caterpillars, lacewing used in conjunction with Trichogramma wasps (see Caterpillar Control) can be very effective. Since Trichogramma attack only the egg stage, the lacewing offers a second line of defense; it feeds on eggs and young caterpillars.