Brood X Periodical Cicadas
Martha Maletta, Home Horticultural Consultant
Dated - May 21, 2004

Brood X periodical cicadas have been getting a lot of press recently and generating a lot of questions to the Rutgers Master Gardener Helpline. They are likely to begin emerging in NJ this week, if they have not already started. How much of a visitation Hunterdon County experiences remains to be seen. But those areas that last saw Brood X in 1987 and have not undergone development or other change that would have disturbed cicada nymphs during their 17-year youth and adolescence underground can expect to encounter them again.

The cicada emergence is really more a curiosity of nature and, perhaps, a big nuisance than a hazard. These sizable flying insects – adults are about 1 and 1/2 to 2 inches long – do not feed on plants to any significant extent. These are not the locusts of plague fame, although they are known, erroneously, as 17-year locusts. They do not bite or sting. They can be intimidating by their numbers – in the past up to 1 million insects per acre have been reported, their erratic, clumsy flight, and their noise. Groups of male cicadas “sing” in unison during the day, creating quite a din. They also “squawk” if disturbed or handled.

There are a few considerations and cautions relevant in areas of expected emergence. Consider alternative plans for outdoor events in late May and June if the noisy, flying insects would be a problem. Delay planting new trees and shrubs until fall, and plan to cover already planted new trees and shrubs with cheese cloth or other fine mesh net to protect against cicada egg laying damage.

Eggs are deposited in slits made by the female in stems of woody plants. On large trees and shrubs this damage is not important but may be on small plants. Female cicadas prefer stems about 1/4 to 1-inch diameter. Many species of trees and shrubs are used, but oak, maple and various fruits are preferred. Conifers are unlikely to be damaged. Don’t know if cicadas will be a problem? Wait and listen. If the males’ “song” is heard, there will be a few days leeway before egg laying begins during which protection could be installed.

Cover small ornamental ponds to prevent large numbers of insects from drowning and fouling water. Gutters may become plugged with cicadas’ bodies. Dogs, cats and many wild creatures enjoy snacking on cicadas with reportedly no ill effects. Cicadas, before they molt, are apparently fit for human consumption, too! For more information (but no recipes), request the Rutgers Fact Sheet on periodical cicada from the Rutgers Master Gardener Helpline of Hunterdon County, 908-788-1735, or visit the publications section of the RCE website at .

The periodical cicadas live only a few weeks and should be gone by the end of June. If they are not appearing in your neighborhood, try to visit an emergence area to experience this unique phenomenon. There are many websites devoted to these insects. A good place to start is the University of Maryland site: