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Billions of cicadas are coming as two rare broods emerge
Submitted by Virginia Tech
April 24, 2024; 9:40 p.m.

cicada
Photo credit: Doug Pfeiffer


Newswise — For the first time in more than 200 years, billions of cicadas - two different broods - will emerge from the ground at the same time. These two different broods have not been seen together since the 1800s. But, as Virginia Tech entomologist Doug Pfeiffer explained not everyone will see this once in a lifetime spectacle.

“Beginning anytime between late April to June, Brood XIX and Brood XIII will emerge in 17 states from the Southeast to the Midwest,” said Pfeiffer. “The timing all depends on soil temperatures. Urban development also affects where we will see cicadas. These insects need trees--hosts longed-lived enough to support multiple generations of 13-year life cycles.”

According to Pfeiffer, unlike annual cicadas which pop up every summer, these periodical cicadas only emerge on a 13 or 17-year cycle. “Annual cicadas can be seen globally while periodicals are only found in North America. We expect Brood XIII to emerge in the Midwest and Brood XIX across the South. Illinois is the location where the two will intersect.” Annual cicadas have black-green coloring, while periodical cicadas have black-red-orange coloring.





“The first sign that cicadas are coming are holes in your lawn, and then that distinctly loud humming will begin before they mate and die,” Pfeiffer said. “All of this lasts anywhere from four to six weeks.”

While their sound can be deafening and they are large in numbers, they are good for the environment and harmless to humans and pets. “They aerate the soil and periodically supply large pulses of nutrients into the soil. They are non-toxic and provide food for many animals.”

Pfeiffer warns that you will want to protect your plants. “The main concern is young fruit trees and grapevines. Cicadas lay eggs in twigs so it is a good idea not to plant fruit trees a year or so before a known emergence.” He also recommends using netting to protect trees while adults are active. “Insecticides can be applied to protect trees from egg-laying, but the effective materials are broad spectrum and the pest manager will have to be watchful for outbreaks of secondary pests.” He said repeated sprays will likely be necessary. “Recent research has indicated that adult cicadas feed on plant sap, but cicadas are generally not a concern for home gardeners.”

Read more from Pfeiffer here about protecting vulnerable plants.

Doug Pfeiffer is a professor in the Department of Entomology with the College of Agriculture and Life Sciences at Virginia Tech and a Virginia Cooperative Extension specialist. Pfeiffer’s work primarily focuses on fruit integrated pest management and ecological interactions in vineyard, small fruit, and orchard systems. He teaches courses on the topic, as well as insect structure and function. Pfeiffer also maintains the Virginia Fruit blog.




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