Adult Colorado potato beetles have bright yellow wings with black stripes. Behind the head is a orange vest with black spots. - USDA APHIS archives, www.insectimages.org

The red humpback larvae have 2 rows of black dots down each side and eat many times their weight in leaves. - USDA APHIS archives, www.insectimages.org

Often present in hordes, Colorado potato beetles ravage potato and other plants by eating the leaves to the point where the plants are completely stripped of foliage. When potatoes plants are not available, they may feed on eggplant, tomatoes, peppers, and even petunias. They'll ravage those, too.

In spring, adults emerge from wintering in the ground or in garden refuse to lay eggs on the foliage. These quickly hatch into red larvae that eat more and more as they grow. The larvae then fall to the ground to pupate and emerge as striped adult beetles that will fly to other plants. You must control them quickly, or the beetles severely weaken the plants and reduce the harvest by stripping the plant of its energy-making foliage.

To control, handpick a small infestation, or spray a large number with insecticidal soap or Neem oil. Be sure to coat the beetles with the spray. They are hard to kill and many have developed resistance to long-used pesticides.

Look for clusters of red-orange eggs on the underside of the leaves and remove them if possible. If not, be sure to spray again in 3 to 5 days because they will hatch into another batch of pests.

To help prevent new infestations each year, clean up the crop as soon as it is harvested. Don't let parts of plants stay around, even dead ones. This is a good practice to prevent lots of problems, not just beetles.

You can also help protect your plants with a floating row cover. This is a lightweight piece of white spun fabric that lets sunlight, air, and water through but lays over the plants like a blanket. When plants are covered, any beetles flying in can't get to the leaves.

A Little Beetle  History

These pests were originally native to the eastern side of the Rocky Mountains, where they fed on the buffalo bur, a plant native to the area. After potatoes were introduced to this region, the beetles decided that they liked them, too, and began spreading eastward via potato fields, reaching the East Coast by 1874. They've been a menace ever since, both to farmers and gardeners.