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Beginner

Scientific Names
Green lacewings (Chrysopidae): Chrysopa nigricornis (Burmeister), Chrysopa oculata (Say), C. carnea (Stephens)
Brown lacewings (Hemerobiidae): Hemerobius humilinus (L.).

Identification
Eggs:

• Less than 1 mm in length, oval and pale.
• Laid individually or in small groups:
• at the end of long silken stalks attached to leaves (green lacewings) or,
• without a stalk (brown lacewings). 

Larvae:

• Three larval instars.
• 0.6-1.2 cm in length, with a long pointed body and a mottled appearance at maturity.
• Well-developed legs and heads with large sickle-shaped mandibles.
• Some species of green lacewing larvae cover their bodies with debris for protection. 

Pupae:

• White silken cocoon.
• Round (green lacewings) or loosely constructed (brown lacewings).

Adults:

• Up to 15 mm long.
• Green or brown.
• Long antennae, large eyes and large veined wings held roof-like over the body.

Often Confused With

• Ladybug larvae – their sickle shaped mandibles and their colouring can distinguish Ladybug larvae.

Interaction With Host
Adults and larvae belonging to the brown lacewing group are predaceous generalist feeders, while only the larvae of the green lacewings feed on other insects and mites. Green and brown lacewing eggs, larvae and adults are all commonly observed in apple orchards.   Lacewing larvae are voracious predators and feed on aphids, phytophagous mites, lepidopteran eggs and other lacewings. Larvae use their mandibles and maxillae to pierce prey and suck out their body fluids. Adult green lacewings are not predaceous and require aphid honeydew and plant nectar as food prior to egg laying.

Period of Activity
Petal fall through harvest.

Insects attacked
Lacewing larvae are voracious predators and feed on aphids, phytophagous mites, caterpillar eggs and other lacewings.

Monitoring and Management
Lacewings are active in orchards from late May until early September. Check for lacewings (eggs, larvae) by visual examination of terminals when monitoring aphid populations. The presence of lacewings and other aphid predators can delay or prevent the need of insecticide applications for green apple aphids.

Lacewing adults and larvae can be monitored in orchards with beating trays. The number of lacewing larvae needed for effective pest control has not been established. Larvae can be most easily detected by examining active aphid colonies on the undersides of leaves. Eggs are usually laid near aphid colonies and can be monitored at the same time as the larvae.  Lacewing larvae are active earlier in the season than many other predators and are good biological control agents for early season pests.

Advanced

Scientific Names
There are several species of green (Chrysopidae) and brown (Hemerobiidae) lacewings commonly found in apple orchards. Common species include the green lacewings Chrysopa nigricornis (Burmeister), Chrysopa oculata (Say), C. carnea (Stephens) and the brown lacewing Hemerobius humilinus (L.). C. carnea is considered the most abundant.

Identification
Eggs: Eggs are less than 1 mm in length, oval and pale. Depending on the species, eggs are laid individually or in small groups, either at the end of long silken stalks attached to leaves (green lacewings) or without a stalk (brown lacewings). 

Larvae: Mature larvae are 0.6-1.2 cm in length, with a long pointed body and a mottle appearance. They have well-developed legs and heads with large sickle-shaped mandibles. Lacewings have three larval instars. Some species of green lacewing larvae cover their bodies with debris for protection. 

Pupae: white silken cocoon (round for green lacewings and loosely constructed for brown species)

Adults: Adults are up to 15 mm long, green or brown in colour, with long antennae, large eyes and large veined wings held roof-like over the body.

Often Confused With

• Ladybug larvae – their sickle shaped mandibles and their colouring can distinguish Ladybug larvae.

Interaction With Host
Larvae of both green and brown lacewings, as well as adult brown lacewings, are voracious predators and feed on aphids, phytophagous mites, beetle eggs, lepidopteran eggs, and other lacewings. Larvae use their mandibles and maxillae to pierce prey and suck out their body fluids.  Occasionally, they pierce plant tissue for moisture or food. Lacewings are best known as aphid predators.  Consumption rates of 44-105 aphids/day and 1,000 mites/day have been reported.  Green lacewing adults are not predaceous and require aphid honeydew and plant nectar as food prior to egg laying. 

Period of Activity
Lacewings are active petal fall through harvest. Green and brown lacewing eggs, larvae and adults are all commonly observed in apple orchards. Most lacewings overwinter as pupae in cocoons, although Chrysoperla carnea overwinters as an adult. Adults emerge in early spring and disperse. Breeding continues throughout the summer. Lacewings have three to four generations per year in Ontario. Brown lacewings are active earlier in the season that green lacewings.

Insects Attacked
Lacewing larvae are voracious predators and feed on aphids, phytophagous mites, caterpillar eggs and other lacewings.

Monitoring and Management
Lacewings are active in orchards from late May until early September. Check for lacewings (eggs, larvae) by visual examination of terminals when monitoring aphid populations. The presence of lacewings and other aphid predators can delay or prevent the need of insecticide applications for green apple aphids.

Lacewing adults and larvae can be monitored in orchards with beating trays. The active adults are best sampled in the cool morning hours. The number of lacewing larvae needed for effective pest control has not been established. Larvae can be most easily detected by examining active aphid colonies on the undersides of leaves. Eggs are usually laid near aphid colonies and can be monitored at the same time as the larvae.  Lacewing larvae are active earlier in the season than many other predators and are good biological control agents for early season pests.