Biology and encouragement of lacewings (a natural enemy of field crop pests)

There are two important families of lacewings (Order: Neuroptera) for pest control: green lacewings and brown lacewings. 

Eggs are laid in groups, attached to vegetation.

Larvae have distinct, arrow-shaped, brown bodies with large pincers. They sometimes attach remains of their prey to their backs as camouflage.

Adults have large, translucent wings that are held roof-like above their bodies. Their wings are longer than their bodies.

Green lacewings (Chrysopidae) – 20 species

• Green bodies and golden eyes
• 20–25 mm long
• Females lay 150–600 eggs each

Brown lacewings (Hemerobiidae) – 31 species

• Brown or grey bodies
• 6–25 mm long
• Less noticeable than green lacewings
• Females lay 600–1,500 eggs each

Lacewings can produce several generations per year. Eggs develop in 6–30 days. There are three predatory larval stages. Larvae may also feed on extrafloral nectaries. Pupation occurs in a cocoon on plants and overwintering can occur either at this stage or as adults.

Larvae and adults usually prey on soft-bodied insects, especially aphids, although adults may also consume nectar, yeasts, pollen and honeydew.

Lacewings can respond to chemical cues associated with aphids. The number consumed by each larva varies but can exceed 1,500. Their effectiveness in controlling aphid outbreaks is, however, uncertain.

Unknown.

Adults may be attracted by flower-rich areas and plants that support aphids. They are attracted to strips of buckwheat. There are two important families for pest control: the green and the brown lacewings.