Species

Green lacewings (Chrysopa spp. and Chrysoperla spp.) belong to the order Nueroptera, family Chrysopidae.

Identification

Life Cycle

Females lay eggs in the spring and summer among leaf litter, twigs, and areas close to prey. It is at the larval stage that green lacewings prey on pests. The larvae hatch within 6 days and go through 3 instars (short development stages) before becoming adults. During the third instar larvae pupate into a silky, loose spherical cocoon which is attached to plants or bark. They emerge as adults within two weeks.

Prey

Green lacewings feed on soft-shelled insects such as:

• Aphids
• Caterpillars
• Leafhoppers
• Mealybugs
• Psyllids
  
  
  Not all species of green lacewings are effective predators of all of pests listed above. Pest species should be determined in order to choose an effective species of lacewing.
  
  

Function

Green lacewings are generalist predators of many small insects in the garden. They actively seek out prey, especially aphids, and use their large front pincers to attack and feed. These pincers serve to both first their prey and then suck out the body fluids for feeding.

The larvae of green lacewing larvae are also known as aphid lions due to their ability to feed on several hundred Aphids during the larval stage.

Commercial Availability

Green lacewings are commercially available, and are some of the most commonly released predators for biological control of pests.

Releasing eggs is often the most inexpensive method, but may be less effective than releasing larvae because of predation of eggs. It might be more effective to keep eggs in a closed container at room temperature until they begin to hatch into larvae before release.

Handling and Use

Eggs can be purchased stuck on a card, which can be left near plants with pest infestations. Follow directions that accompany purchases of green lacewings.

A common mistake made in releasing at the egg stage is to place them in cups which are vulnerable to rainfall collecting in them and drowning the insects.

• Always follow directions provided by distributor.
  
  

Cultivation Techniques

Nectar producing flowers increase food supplies for adult lacewings and encourage population growth.

• Refer to "Farmer" Fred Hoffman's Beneficial Insect Guide for plant choice ideas.

Wheast (a product which combines wheat and yeast) is commercially available as a supplementary food spray. It will provide lacewings another source of food. However, wheast can be expensive. A cheaper alternative is a homemade mixture of yeast and sugar.

References

"Nautral Enemies Gallery: Green Lacewings—UC IPM." 2004. The University of California. 25 June 2008. <http://www.ipm.ucdavis.edu/PMG/NE/green_lacewing.html>.

Flint, Mary Louise. Pests of the Garden and Small Farm: A Grower's Guide to Using
Less Pesticide. University of California, 1999.

Flint, Mary Louise, and Steve H. Dreistadt. Natural Enemies Handbook: The Illustrated Guide to Biological Pest Control. Berkeley: UC Division of Agriculture and Natural Resources and the University of California Press, 1998.

Weeden, C.R., A. M. Shelton, and M. P. Hoffman. "Chrysoperla spp."
Biological Control: A Guide to Natural Enemies in North America.
Cornell University. 27 Sept. 2008. <http://www.nysaes.cornell.edu/ent/biocontrol/predators/chrysoperla.html>.