Lacewings belong to the order Neuroptera. The Green lacewing, Chrysoperla sp. belongs to the Chrysopidae family. Adults are green and the lacy wings fold over the body.
These flying insects lay their eggs either singly or in small groups, and each egg is always perched on the tip of a hair-like stalk, which helps to reduce cannibalism of the eggs by other larvae.
Larvae are brown and white and are often called aphid lions, as they are excellent predators on aphids. However, they don’t only feed on aphids, but also other soft-bodied insects, small cabbage worms, other caterpillars, mealybugs and whiteflies. In addition, the larva of the green lacewing is a well-known biological control agent.
Lacewing larvae are natural predators on the following pest species:
- Grapevine mealybug, Planococcus ficus, in vineyards.
- Diamond-back moth, Plutella xylostella, which targets members of the Brassicaceae family.
- Cotton aphid, Aphis gossypií, which is a common pest on hundreds of recorded host plants.
- Yellow pecan aphid, Monelliopsis pecanis, which is a pest species on pecan trees.
- Citrus psylla, Trioza erytreae, which is a common pest on the leaves of Rutaceae trees.
- White powdery scale, Pseudocribrolecanium andersoni, a common pest on a variety of cultivated plants.
- Citrus thrips, Scirtothrips aurantii, a common pest on host plants with aromatic oils or terpenoids.
- Aloe aphid, Aloephagus myersi, a common pest on Aloes, Gasteria and Haworthia.
- Red scale, Aonidiella aurantii, a common pest on many indigenous and exotic trees and shrubs, and many members of the Rosaceae family.
The above examples emphasize the importance of lacewings to control various infestations of pest species. In most species, adults feed on pollen and honeydew. The adult stages of some species are also predatory.
To attract lacewings to your garden, you can do the following:
· Tolerate light outbreaks of aphids, as they are an important food source for lacewing and ladybug larvae.
· Remove covers from plants during the evening so that lacewings can scout for pests.
· Prevent the use of pesticides when lacewings are active.
· When you notice an aphid problem that needs immediate attention, spray the plants with a light solution of sugar and water (1 tablespoon sugar per 250ml water). The sugar water simulates aphid honeydew, which can quickly increase the visits of lacewings and ladybugs.
Plants that are known to attract lacewings
The adult lacewings are often seen in and around the house at night. You can easily recognize them on a wall, especially when the wall is painted a light colour – the green colour of the lacewing is then conspicuous. Appreciate these lacewings, as they are essential biological control agents.