Green Lacewing - Chrysoperia carnea

THE "APHID LION"

After a few days, the eggs hatch and tiny larvae emerge which are also known as"aphid lions" because of their voracious appetite. There is no other better predator known to consume vast quantities of eggs and the soft bodies of aphids, mealy-bugs, spider mites, leafhopper nymphs, caterpillar eggs, scales, thrips, and white-flies. The lacewing larvae attack the eggs of most pests and, if the bodies are not to hard and fast moving, will attack the adult pest stage as well.

Use lacewing eggs/larvae for greenhouses and gardens. Larvae will only feed for 1-3 weeks before they become adults (eating only nectar and honeydew). Use approximately 10 lacewing eggs/larvae per plant or 1000 eggs per 200 square feet. After a few days, the eggs hatch and tiny larvae emerge. The larvae are gray-brown in color and newly hatch are very tiny. Similar in appearance to an alligator with pincers, the lacewing larvae vigorously attacks its prey, injects a paralyzing venom, and draws out the body fluids of its helpless victim. Depending on climate conditions, the adults will live for about four to six weeks, feeding only on nectar, pollen and honeydew. If these food sources are not avalable, it will simply leave the area and lay its eggs elsewhere.

Green lacewing eggs are shipped in bran or rice hulls and packed with moth eggs for food. The best time to release is early morning or later afternoon. Never release in the heat of the day. For best results, immediate use is advised however, when release is inconvenient, they can be stored in the refrigerator for up to 48 hours. Warmer temperatures will speed up their emergence and newly hatched lacewing larvae are hungry and will cannibalize each other if they are not released quickly.

Use lacewing eggs/larvae for greenhouses and gardens. Larvae will only feed for 1-3 weeks before they become adults (eating only nectar and honeydew). Use approximately 10 lacewing eggs/larvae per plant or 1000 eggs per 200 square feet. After a few days, the eggs hatch and tiny larvae emerge. The larvae are gray-brown in color and newly hatch are very tiny. Similar in appearance to an alligator with pincers, the lacewing larvae vigorously attacks its prey, injects a paralyzing venom, and draws out the body fluids of its helpless victim. Depending on climate conditions, the adults will live for about four to six weeks, feeding only on nectar, pollen and honeydew. If these food sources are not avalable, it will simply leave the area and lay its eggs elsewhere.

Green lacewing eggs are shipped in bran or rice hulls and packed with moth eggs for food. The best time to release is early morning or later afternoon. Never release in the heat of the day. For best results, immediate use is advised however, when release is inconvenient, they can be stored in the refrigerator for up to 48 hours. Warmer temperatures will speed up their emergence and newly hatched lacewing larvae are hungry and will cannibalize each other if they are not released quickly.

If the infestation has not been arrested after 5 to 7 days, additional releases may be necessary. When releasing on a regular schedule, change the release sites within the target area to get maximum coverage.

If the infestation has not been arrested after 5 to 7 days, additional releases may be necessary. When releasing on a regular schedule, change the release sites within the target area to get maximum coverage.

Biology and Life cycle

Adults generally live from 1-3 months depending on temperature, humidity and quality of food sources. Females can lay several hundreds of eggs; however, fecundity is known to depend on mating activity and food quality. Lacewing eggs are very unique in that they are placed (singly) at the top of a thin "hair-like" support (ca. 3/8 inch in length). The incubation period (development time) of the eggs depends on lacewing species and temperature. The developmental time, however, does not appear to be affected by relative humidity (ranging from 20-80%). For some Chrysoperla species, the incubation period can vary from 2-3 days at 95ºF (35ºC), to approximately 4 days at 77ºF (25ºC), and 6-7 days at 68ºF (20ºC). Females tend to lay their eggs close to future sources of prey, to facilitate rapid and successful searching by the young lacewing larvae. Larvae develop through three instars. Each larva is capable of devouring 200 or more aphids, or pest eggs, per week, during its developmental period. After 2-3 weeks, larvae will pupate in a spherical silken cocoon, usually attached to the vegetation. The pre-pupal and pupal stages last about 5-8 days. Adult emergence occurs after 1-2 weeks depending on temperature, relative humidity, and trophic condition. The life cycle can be lengthened in temperate regions where green lacewings undergo a period of diapause and overwinter as adults in dry and dark places (e.g., under the leaf litter, and physical structures).

Impacts on Insects

Impact on Horticultural and Field Crop Pests

Lacewing larvae are known to feed on a wide variety of soft-bodied arthropods including many aphid species, caterpillars, insect eggs, spiders and mites. The use of lacewings to control arthropod pests have been reported for several crops, worldwide (e.g., Canard et al. 1984). For example, releases of second-instar larvae have proven to be successful for the control of the green peach aphid in peppers, tomato and eggplant. In addition, lacewing larvae have been used to control other pests such as the Colorado potato beetle, European red mite, different species of mealybugs, corn earworm and the tobacco budworm.

The efficiency of lacewings to control pests can be affected by many factors, including: pest type, distribution of the pest (e.g., within and among plants), weather, crop, number of predators released, stage of predator released, and the predator/prey ratio. The efficiency of pest control can be increased in small scale production systems by manipulation of the environment (e.g., food supplement, attractants, and crop inter-planting), in which the predators are to be released. In addition, a combination of predator releases and environment manipulation will increase the odds of success.

Impact on Greenhouse Pests

The use of green lacewings in greenhouses can be effective by using multiple or inundative releases. Green lacewing larvae or eggs of the predator can be released to control pests in greenhouses. However, if control is needed in a short period of time, the larval stage is the recommended stage to be released. Good to excellent control has been reported when the predator-prey ratio is between 1:3 to 1:5. The interval between predator releases for optimum pest control in the greenhouse varies depending on the pest species, environmental conditions and potential for crop damage.

For both field and greenhouse pest management, the use of green lacewings can be an effective component of IPM. Green lacewings have also been reported to have a degree of resistance to a number of insecticides. This insecticide resistance can be favorable to maintain predator populations, even when a chemical treatment is needed to mitigate the unexpected increase of pests.

Green Lacewing eggs are oval and pale green. Just before the larvae hatch, eggs turn gray. The eggs are shipped in vials with food and a carrier such as rice hulls, bran or vermiculite. It is best to allow a few of the lacewing larvae to begin emerging from the eggs before releasing. As soon as a few emerge, release as soon as possible to avoid cannibalism. The best time to release is early morning or late afternoon. Eggs can be stored at no lower than 50°F for up to 48 hours. Lacewing larvae are grey-brown in color and very tiny when just hatched, so you may need a magnifying glass to see them. Looking like tiny "alligators", lacewing larvae voraciously attack almost any prey they can grab, using pincer-like jaws. After injecting a paralyzing venom, they suck the body fluids from their helpless victim.

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