- Author: Linda Lewis Griffith
- Editor: Noni Todd
Beneficial Insects
By Linda Lewis Griffith UCCE Master Gardener
There is an army of tiny predators in your garden, busily keeping harmful pests at bay. Here are a few you may encounter:
Adult convergent lady beetles are easily recognized by their shiny, convex, half-dome shape and short antennae. They can have up to 13 black spots on their forewings. But many have fewer spots and some individuals have none. Both adults and larvae eat aphids. They also feed on whiteflies, other soft-bodied insects and insect eggs. One species, Hippodamia, is frequently sold at gardening outlets. But their tendency to disperse even if food is abundant makes them of little use.
Green lacewings are soft-bodied insects with four membranous wings, gold eyes and green bodies. Adults can fly at night and are usually seen when they're drawn to lights. Some species are predaceous; others feed on honeydew, nectar and pollen. Larvae prey on a wide variety of insects, including mealybugs, psyllids, thrips, mites, whiteflies, aphids, small caterpillars, leafhoppers and insect eggs. Green lacewings are commercially available and are among the most commonly released predators.
Predaceous ground beetles of the Carabid family are medium to large soil-dwelling beetles that are 1/3 to 2/3 inches long. Over 2,500 species are known in North America. Adults are often black or dark reddish, although some species are brilliantly colored or iridescent. Adults and larvae feed on insect larvae and pupae in the soil, invertebrates such as snails and slugs, and sometimes on seeds and organic litter. You can attract these and many other natural enemies to your garden by following a few simple steps:
· Avoid using pesticides that kill both harmful and beneficial insects
· Choose plants that provide beneficial insects with pollen, nectar and shelter
· Keep ants out of pest-infested plants.
Learn more about beneficial insects at the Advice to Grow By workshop Saturday, February 20, from 10:00 to 12:00 at 2156 Sierra Way, San Luis Obispo. If inclement weather, the workshop will be held in the auditorium across the parking lot from the garden.