Beneficial Predator Spotlight: Lacewings

May 20, 2017

Green lacewing life cycle.[J.K. Clark]
Green lacewing life cycle. [J.K. Clark]
Last week, we discussed some common beneficial predators that help control pests on garden and landscape plants. One such predator you might find, is a lacewing. In fact, you may have seen adult lacewings on or near porchlights in the evening, since these insects are attracted to lights.

Green Lacewings

Green lacewing (Chrysopa spp., Chrysoperla spp.) adults are green, soft-bodied insects with golden eyes and four membranous wings. Their larvae are pale with dark markings and a tapered tail, and measure 1/8 to 4/5 of an inch long.

There are several species of green lacewings; some species have predaceous adults, while others feed only on honeydew, nectar and pollen. Larvae look like tiny alligators and are generalist predators on mites and small insects, including aphids, caterpillars, leafhoppers, mealybugs, psyllids, thrips, whiteflies, and insect eggs.

If you look carefully, you may see green lacewing eggs on plants in your landscape. Eggs are laid in clusters, or singly, each on an individual silken stalk.

Brown Lacewings

Brown lacewing life cycle. [J.K. Clark]
Brown lacewing life cycle. [J.K. Clark]
Brown lacewings (Hemerobius spp.) are less commonly seen in gardens and landscapes than green lacewings. They are also much smaller. The adults are about half the size of green lacewing adults, measuring only 3/8 of an inch long. Brown lacewing larvae look like tiny alligators too, but are creamy-brown with dark reddish-brown stripes and spots. A distinguishing behavior is that they move their heads from side to side when walking.

Both adults and larvae prey on various small insects including mealybugs, psyllids, thrips, mites, whiteflies, aphids, small caterpillars, leafhoppers, and insect eggs.

Protect Natural Enemies

Protect lacewings and other beneficial predators in the garden by avoiding using certain pesticides that can kill them, and choosing plants that provide pollen, nectar, and shelter. You'll also want to keep ants out of pest-infested plants. Watch the video, “Using a Sticky Barrier to Keep Ants out of Trees” for instructions.

Visit the Natural Enemies Gallery on the UC IPM Website to learn more about lacewings.

 


By Anne Schellman
Author - UC Master Gardener Coordinator