1 Lacewing per 20 pests or 2 per sq. ft. 10,000-50,000 per
acre per year
RELEASE INSTRUCTIONS & NOTES
Larvae are shipped in a bottle with a small amount of food,
& should be released immediately because they will cannibalize each other.
A common green lacewing (scientifically known as Chrysoperla
rufilabris) is widely used in various situations to control many
different pests. Many species of adult lacewings do not kill pest insects, they
actually subsist on foods such as nectar, pollen and honeydew. It is their
predacious offspring that get the job done.
The adult lacewing lays her eggs on foliage. Each
egg is attached to the top of a hair-like filament. After a few days the eggs
hatch and a tiny predatory larva emerges ready to eat the pests.
Lacewing larvae are also known as aphid lions.
They are tiny upon emerging from the egg, but grow to 3/8 of an inch long.
Lacewing larvae voraciously attack their prey by
seizing them with large, sucking jaws and inject a paralyzing venom. The hollow
jaws then draw out the body fluids of the pest. Of all available commercial
predators, this lacewing is the most voracious and has the greatest versatility
for pests of field crops, orchards, and greenhouses.
Each lacewing larva will devour 200 or more pests
or pest eggs a week during their two to three week developmental period. After
this stage, the larvae pupate by spinning a cocoon with silken thread.
Approximately five days later adult lacewings emerge to mate and repeat the life
cycle. Depending on climatic conditions, the adult will live about four to six
Each adult female may deposit more than 200 eggs.
For best results, habitats should be provided that encourage the adults to
remain and reproduce in the release area. Nectar, pollen, and honeydew stimulate
their reproductive process. If these food sources are not available, adults may
disperse. An artificial diet called Wheast is available to provide the
adults with the necessary nutrition they need for reproduction. Wheast
powder mixed with sugar and water is used to help mass-rear the lacewing.
Studies by universities and the USDA have shown that spraying field crops with a
Wheast/sugar/water mixture increases egg laying considerably. Lacewing
adults can survive the winter in protected places but have a difficult time
surviving cold winters.
Lacewing larvae feed on many different pest
insects. In general, they attack the eggs and the immature stages of most
soft-bodied pests such as: aphids, thrips, spider mites, sweet potato &
greenhouse whitefly, mealybugs, leafhoppers, and the eggs and caterpillars of
most pest moths.
When targeting caterpillars, lacewing used in
conjunction with Trichogramma
wasps can be very effective. Since Trichogramma attack only the egg
stage, the lacewing offers a second line of defense; it feeds on eggs and
young caterpillars. Information about the use of Trichogramma is available from
Bioscape, Inc., as are recommendations of pertinent scientific literature.
PEST MANAGEMENT USING LACEWING
Start early in the season as soon as pest insects
are detected. Monitoring is essential. Traps and lures can be very helpful tools
for establishing "start dates" and for predicting pest population
levels. Initiating natural enemy releases when pest populations are high does
not lend itself to successful augmentative biological control. The pest must be
detected and releases begun when infestations are at a manageable level. Because
every situation is different, numbers of lacewings required can vary
significantly from site to site. It is therefore important to monitor the
beneficial insect and pest populations.
Generally, it is best to start with early release
of a relatively low number of lacewings per acre or target planting. It is
essential to refrain from using broad spectrum chemicals in order to conserve
naturally occurring predators and parasites. Lacewings should be released every
10 - 15 days until their populations are easily detectable or pests are no
longer a threat.