Cucumber beetles are a serious pests of cucurbit (cucumbers and squash), melons, and pumpkins. They prefer tender, succulent portions of plants, including the flowers, which may be destroyed by their feeding. The beetles chew holes in leaves and scar runners and young fruits. Adults tend to avoid heat and thus feed mainly on the underside of young melons. After the skin hardens, melons are much less subject to attack. Scarring in the crown of the plant is also typical of adult damage. Feeding on stems of young plants, followed by sustained winds, may result in severe stand reductions making replanting necessary. In some situations, larvae may cause serious injury by feeding on roots, and young plants can be killed. Cucumber beetles also spread squash mosaic virus and a bacterial wilt. The striped cucumber beetle overwinters as an unmated adult in fields, under fallen leaves, hedgerows and in garden debris. Adults emerge in early spring and feed on native food sources. Once a preferred food source, such as squash or melons, is available the adults migrate there and begin to reproduce. The larvae will feed on the root systems for two to six weeks before pupating in the soil. Emerging as adults, they then feed on tender garden vegetation. It is possible to have multiple generations within one growing season. Some natural deterrent techniques include: --rotating crops to a new place in the garden every year, --depriving adult beetles of homes for overwintering by removing debris from the garden, --removing asters and goldenrods--native hosts to the beetle--from the garden proximity to possibly persuade them to move to more inviting yards, --covering planting beds with floating row covers immediately after planting to provide early protection. (Row covers must be removed when the plants are flowering to allow for pollination.) Cucumber beetles are attacked by a variety of natural enemies, the most important being a parasitic tachinid fly, Celatoria diabroticae. Natural enemies are rarely effective enough, however, to reduce populations below economically damaging levels. Some chemicals, both man-made and botanical, will control the beetles. Mehoxychlor, carbaryl, totenone, and pyrethrum are registered for use in home gardens. Most insecticides are harmful to the honey bees and pollinating insects that the plants require, so care must be taken with timing of applications. Read the chemical labels carefully to protect the toads. Carbaryl is known to be a problem for frogs and toads.

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