Bring on the bugs: A guide to beneficial bugs and pests

Cabbage worms (pest): These medium green, 1-inch long caterpillars have faint yellowish strips along their sides. The adults are white butterflies with two or three black dots on each upper wing. Left unchecked, these are serious pests to cabbage-family crops, eating ragged holes in leaves and hiding in cabbage and broccoli heads.

Cabbage worms (pest, adult): These medium green, 1-inch long caterpillars have faint yellowish strips along their sides. The adults are white butterflies with two or three black dots on each upper wing. Left unchecked, these are serious pests to cabbage-family crops, eating ragged holes in leaves and hiding in cabbage and broccoli heads.

Army worms (pest): The 1- to 2-inch caterpillars come in colors from greenish-blue to brown, and usually have prominent stripes down their sides. These pests feed at night or on cloudy days and will chew holes in leaves and fruit.

Colorado potato beetles (pest): The larvae look like a dull reddish orange blob, with a black head and legs. The adults have shells with black and yellow stripes. Although called potato beetles, they affect eggplant, pepper and tomato, too, and actually prefer eggplant to potato.: The larvae look like a dull reddish orange blob, with a black head and legs. The adults have shells with black and yellow stripes. Although called potato beetles, they affect eggplant, pepper and tomato, too, and actually prefer eggplant to potato.

Colorado potato beetles (pest, adult): The larvae look like a dull reddish orange blob, with a black head and legs. The adults have shells with black and yellow stripes. Although called potato beetles, they affect eggplant, pepper and tomato, too, and actually prefer eggplant to potato.

Corn earworms (pest): Affecting corn, bean, pea, pepper, potato, squash and tomato, earworms are 1-inch long caterpillars that range in color from green to brown to yellowish tan and have dark stripes down their sides. On corn, the earworm eats the silk before moving into the ear. On other crops, it feeds on stems, leaves and fruits.

Corn earworms (pest, adult): Affecting corn, bean, pea, pepper, potato, squash and tomato, earworms are 1-inch long caterpillars that range in color from green to brown to yellowish tan and have dark stripes down their sides. On corn, the earworm eats the silk before moving into the ear. On other crops, it feeds on stems, leaves and fruits.

Cucumber beetles (pest): Larvae are white grubs with brown or black heads, while adults are spotted and striped. These beetles feast on cucumber, melon, potato and squash.

Leafminers (pest, beetle larvae): Although referring to a collection of moths, beetles and flies, the leafminer that affects vegetables is a small grayish yellow fly. Larvae resemble small green maggots, which chew tunnels in the leaves of beets, lettuce, spinach, Swiss chard and other leafy greens.

Leaf miners (pest, adult fly): Although referring to a collection of moths, beetles and flies, the leaf miner that affects vegetables is a small grayish yellow fly. Larvae resemble small green maggots, which chew tunnels in the leaves of beets, lettuce, spinach, Swiss chard and other leafy greens.

Mexican bean beetles (pest): The adults look similar to ladybugs, but have copper-colored backs with black dots. Young adults have no spots. Adults and larvae will both feed on bean leaves, leaving skeletonized foliage.

Mexican bean beetles (pest, adult): The adults look similar to ladybugs, but have copper-colored backs with black dots. Young adults have no spots. Adults and larvae will both feed on bean leaves, leaving skeletonized foliage.

Squash bugs (pest): Both nymphs and adults cause horrendous damage to squash, pumpkin, gourd, melon and cucumber plants. Squash bugs pierce the outside skin of plants and suck out the juices, leaving plants with yellow and brown spots.

Squash bugs (pest, adult): Both nymphs and adults cause horrendous damage to squash, pumpkin, gourd, melon and cucumber plants. Squash bugs pierce the outside skin of plants and suck out the juices, leaving plants with yellow and brown spots.

Tomato hornworms (pest): Hornworms may be one of the uglier bugs you encounter. These pale to medium green larvae have white streaks across the body, spots on the side, and a red or black spiky tail. A hornworm can devour most of a tomato plant in a day or two. This picture shows a hornworm caterpillar that has been attacked by the beneficial braconid wasp, hence the white cocoons on the caterpillar’s back. Any large caterpillar with those cocoons should be left alone as it will die soon and the beneficial wasps will emerge and attack more pest caterpillars. The hornworm adults are large, brownish gray moths with orange spots on the abdomen.

Tomato hornworms (pest, adult): Hornworms may be one of the uglier bugs you encounter. These pale to medium green larvae have white streaks across the body, spots on the side, and a red or black spiky tail. A hornworm can devour most of a tomato plant in a day or two. The adults are large, brownish gray moths with orange spots on the abdomen.

Ladybug (beneficial) : Most people know what a full-grown ladybug looks like, but might not recognize the black and orange alligator-shaped larvae, or the pupa pictured here. The adults are aphid-eating powerhouses, but even larvae can consume 50 to 60 aphids a day.

Ladybug (beneficial, adult): Most people know what a full-grown ladybug looks like, but might not recognize the black and orange alligator-shaped larvae. The adults are aphid-eating powerhouses, but even larvae can consume 50 to 60 aphids a day.

Praying mantis (beneficial): When a nymph hatches out of an egg case like the one shown here, it looks like a miniature of the adult. The babies are in danger of being eaten by birds or other bugs, but can camouflage themselves among the leaves. Praying mantises are a bit overrated as beneficials, since they don’t eat much for their size.

Praying mantis (beneficial, adult): When a nymph hatches, it looks like a miniature of the adult. The babies are in danger of being eaten by birds or other bugs, but can camouflage themselves among the leaves. Praying mantises are a bit overrated as beneficials, since they don’t eat much for their size.

Assassin bug (beneficial): Vicious looking as adults, these bugs can give humans a nasty bite if provoked. But they provide important pest control in your garden, killing flies, mosquitoes, beetles and large caterpillars. Their method of killing is quite gruesome. The nymph is pictured here.

Assassin bug (beneficial, adult): Vicious looking as adults, these bugs can give humans a nasty bite if provoked. But they provide important pest control in your garden, killing flies, mosquitoes, beetles and large caterpillars. Their method of killing is quite gruesome.

Green lacewing: The larvae are better at pest control than the adults. Larvae will devour aphids, spider mites, mealybugs, whiteflies and the eggs of caterpillars.

Green lacewing (beneficial, adult): The larvae are better at pest control than the adults. Larvae will devour aphids, spider mites, mealybugs, whiteflies and the eggs of caterpillars.

Hover fly (beneficial): Adults have black and yellow stripes, feed on nectar and lay eggs on leaves of plants. The eggs hatch into ugly little larvae that resemble maggots and feed on aphids and other small bugs.

Hover fly (beneficial, adult): Adults have black and yellow stripes, feed on nectar and lay eggs on leaves of plants. The eggs hatch into ugly little larvae that resemble maggots and feed on aphids and other small bugs.

Spined soldier bug (beneficial, adult): Another gruesome killer, this beneficial is a member of the stink bug family. It’s great for killing hornworms, potato and bean beetles and cabbage worms.

Trichogramma wasp (beneficial): This is one of the best known parasitic wasps. Adults lay their eggs within the eggs of pests like corn earworms, cutworms, cabbage worms and borers. When the eggs hatch, the newborn consumes the embryo of the host.