News & Features Home

‘Good bugs’ play a key role in gardening success

‘Good bugs’ play a key role in gardening success

There’s no way around it—insects are unwelcome guests in most people’s homes, and some residents go to great lengths to expel creepy crawlers from their dwellings.

But in the garden, it’s a whole different story. Whatever your definition of “bugs”, they are a crucial part of supporting plant growth and acting as pest control, pollinators and facilitators of soil regeneration. Of the 10 quintillion insects estimated to be living on Earth, about 99% of them provide positive ecological benefits.

Dr. Doug Pfeiffer, a Virginia Tech entomology professor, offered a few impartial reviews of insects that some may consider harmful.

Bees – Anthophila

Pfeiffer’s review: “Bees have a very positive role in the environment, including the role they have with humans. They’re good because they pollinate a wide variety of plants. Honeybees, bumblebees and mason bees are all useful pollinators.”

Ladybugs – Coccinellidae

Pfeiffer’s review: “Most ladybugs are predatory, but a couple of North American species feed on plants, such as Mexican bean beetles. They can be very effective in reducing mites and aphids. Ladybugs often hunt in ground cover and in trees. They help control pests on a wide variety of horticultural crops.”

Praying mantises – Mantidae

Pfeiffer’s review: “Praying mantises are almost entirely predatory, and they often catch pest insects. However, it’s hard for them to really put a dent in a pest population because they’re not all that numerous.”

Ground beetles – Carabidae

Pfeiffer’s review: “Ground beetles are an interesting family because they’re mainly predatory, but some feed on seeds in the ground. Ground beetles often are good predators of caterpillars, and generally they’re good predators of pest insects that spend some part of their life cycles in the ground cover.”

Vespid wasps – Vespidae

Pfeiffer’s review: “The vespid wasps, such as paper wasps and yellow jackets, have a mixed role, mostly because people are leery of them because they can sting. Some species are more aggressive than others, but they’re beneficial during most of the growing season because they feed on caterpillars and other pest insects in farm fields.”

Lacewings – Chrysopidae

Pfeiffer’s review: “There are two main families of lacewings—green and brown. Their larvae are entirely predatory, and they’re sometimes called aphid lions because they’re voracious predators of aphids. Overall, they can be very effective predators of soft-bodied insects. Some species mainly feed on pollen, but I don’t know of any that cause injury to plants.”