News Release

COLUMBUS, OH -- After 17 years in silent seclusion, Ohio's largest brood of periodical cicadas will make their noisy presence known this spring, the Ohio Department of Natural Resources (ODNR) reports. Noted for the distinctive, often annoying hum of their collective mating calls, cicadas can also damage trees and ornamental shrubs in heavily infested areas, ODNR foresters warn.

"Three species of cicadas will emerge in mid-May over much of the eastern half of the state for this first time since 1982," says Dan Balser, with the ODNR Division of Forestry. "Of the 17 to 20 cicada broods nationwide, four exist in Ohio. The brood emerging this spring will number in the billions, making this Ohio's largest and noisiest crop of cicadas. This same brood will also appear in much of West Virginia, the southwest corner of Pennsylvania, western-most Maryland and northwest Virginia," he said.

Harmless to humans, the 1-1/2-inch winged insect can damage deciduous trees, primarily oak, apple, dogwood, and hickory, as well as newly planted ornamentals. While the cicada's roar is produced by a chorus of mate-hunting males, any damage is the work of female cicadas. Each female emerges from the ground to lay hundreds of eggs in inch-long slits she has cut in pencil-sized tree branches. These slits can weaken young or otherwise susceptible trees, killing off the affected branches or leaving openings for disease.

To help reduce cicada damage, Balser recommends to homeowners that they not prune trees this spring. Instead, damaged twigs may be pruned out later this summer, after the cicada invasion has run its course. In affected areas of the state, most tree damage can be avoided by delaying new plantings of woody ornamentals and trees until fall or the following spring. Small shade and ornamental trees can be protected by a covering of cheesecloth or finely woven netting, according to Balser. "This physically prevents females from laying eggs in the twigs. Trees too large to cover may be sprayed with a contact insecticide," he said. "Chemical control is difficult during the peak of the cicada's egg-laying season, because of the large number of cicadas present and relatively slow action of the pesticide." Spraying trees in flower can also harm honeybees, he warned.

For more information regarding insecticide recommendations, homeowners should contact their local extension agent or entomologist, being certain to follow all insecticide label directions carefully.