leafhopper, common name for small, wedge-shaped leaping insects, cosmopolitan in distribution, belonging to the family Cicadellidae, which comprises some 5,500 species of insects. Some are brightly colored and others are green to brown; they generally measure less than 1/4 in. (6 mm) in length. Leafhoppers, and the family as a whole, attack a wide range of trees, shrubs, grasses, and forbs. However, the nymphs and adults frequently suck the sap of only one or a few kinds of plants. Besides stunting plant growth by causing loss of sap, some leafhoppers introduce a toxin into the plant as they feed; others introduce disease organisms.
The potato leafhopper, Empoasca fabae, is a serious pest in the E United States. It causes a disease commonly known as hopperburn on potatoes and damages many other plants, including apples, beans, and clover. As a result of the potato leafhopper's attack, the leaf's conducting tissue is plugged; the plant leaves curl and begin to turn brown near the tip, and eventually the whole leaf appears blighted. As many as 5 to 6 million leafhoppers may be found per acre. Other leafhopper pests include the beet leafhopper, which causes the beet disease known as curly top in the W United States; the grape leafhopper; the rose leafhopper; and the apple leafhopper.
Many leafhoppers have a single generation per year, but there may be several. They overwinter either in the adult or egg stage, depending on the species. Eggs are laid singly or a few at a time in stems and leaves. The adults overwinter only in the south; those migrating north each year cause much damage, but are usually killed by the frost.
Leafhoppers are classified in the phylum Arthropoda, class Insecta, order Homoptera, family Cicadellidae.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.