The emergence of Brood XIV (14) of the 17-year periodical cicadas (Magicicada spp.) is well underway in southern Ohio. This is a relatively large brood affecting 13 states including Georgia, Indiana, Kentucky, Massachusetts, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia.

The emergence involves all three species of the 17-year periodical cicadas: M. cassini, M. septendecim, and M. septendecula. You can learn how to easily identify the three species by visiting this Cicada Mania website:

https://www.cicadamania.com/cicadas/where-will-17-13-year-periodical-cicadas-emerge-next/#species

You can learn more about periodical cicadas, including management options, by accessing our updated 2025 OSU Extension fact sheet titled, “Periodical Cicadas in Ohio,” that was posted in March. Click this hotlink to see the fact sheet: https://ohioline.osu.edu/factsheet/ENT-58

Current Observations

Thus far, I’ve only found M. cassini emerging in southwest Warren County and northeast Hamilton County, OH. Males are beginning to sing with some chorusing. I’ve not yet found mating pairs or oviposition damage. Others have also observed and heard M. septendecim as well as M. cassini in northcentral Clemont County. Image 1 – Image 2 – Image 3

The vast majority of the periodical cicada’s life cycle is spent out-of-site below ground where they suck sap from tree roots as they develop through 5 instars. Cicadas leave the soil at the end of the 5th instar. However, in essence, the 5th instar “nymphs” that emerge from the soil are adults wrapped in the exoskeletons of the final nymph stage.

They crawl up nearby trees, vegetation, or other vertical objects to molt through a process called ecdysis. Cast skins (exuviae) are left behind after the adults emerge. The light-tan to off-white exoskeleton of a newly emerged adult is soft and pliable until it hardens and gains the final coloration and markings. Image

Periodical cicadas emerge in massive numbers to lessen the impact of predation. A brood emergence is marked by large numbers of cast skins attached to trees and littering the ground beneath host trees. Image

However, it’s also common to find cicadas that have failed to emerge from their last instar nymphal skin. In fact, researchers reported in a study published in 1979 (White et al., 1979) that 31% died during ecdysis. The image below isn’t a Quasimodo cicada. It’s what happens when the pliable exoskeleton of a new adult hardens before the cicada can successfully free itself from its nymphal skin. Image

Cooley and Holmes (2023) observed that, “Under extremely high densities, cicadas can disrupt others undergoing ecdysis by knocking them loose from their perches, trapping them, or causing physical damage. Our observations raise the possibility that while periodical cicadas thrive at high densities, it is possible that some densities are so high that they inhibit success.” The image below shows the aftermath of a dastardly cicada that prevented the emergence of a hapless cohort. Image

Nature plays no favorites; it’s survival of the fittest. The cicada that left behind its nymphal skin stands a chance to pass its genes onto the next generation.

Where You Should Look

Cemeteries and parks with old, mature trees are prime locations to experience the emergence firsthand. Keep in mind that the Brood XIV (14) 17-year periodical cicadas spent the past 17 years sucking sap from tree roots. This means that cicadas only emerge from beneath trees that were planted at least 17 years ago. Image

A Word from Management

If you are located where you are seeing cicadas, now is the time to take measures to protect small, newly planted trees. The most effective way to prevent oviposition injury to tree stems is to use 1/4” mesh netting. Image 1 – Image 2

Make plans to remove the netting as soon as the cicada threat passes to limit the negative effects. New growth may become distorted, and the compressed, tightly packed foliage creates a microenvironment conducive to foliar disease development.

Contribute to Science by Participating in a Cicada Safari

Accurately mapping the geographical range of Brood XIV (14) can only occur every 17 years. The last appearance of this brood was in 2008. We need your help!

Gene Kritsky (Professor Emeritus of Biology, Mount St. Joseph University) worked with his university’s Center for IT Engagement to develop the Cicada Safari phone app. You can download the FREE Android or iPhone app by visiting the Apple App Store or Google Play. The app is easy to use, and it takes no time to take a photo and submit it to Cicada Safari.

ADDED BENEFIT: The app includes the locations of cicada sightings made thus far. It’s a great way to plan a trip to view and enjoy this unusual insect event!

Click this hotlink to learn more about Cicada Safari: https://cicadasafari.org/

References Cited

Cooley, J. R., & Holmes, G. (2023). Periodical cicadas (Magicicada spp.): Predator satiation, or too much of a good thing?. The Great Lakes Entomologist, 56(1), 15.

White, J., Lloyd, M., & Zar, J. H. (1979). Faulty eclosion in crowded suburban periodical cicadas: populations out of control. Ecology, 60(2), 305-315.

More Information

OSU Fact Sheet: Periodical Cicadas in Ohio https://ohioline.osu.edu/factsheet/ENT-58

Ron Wilson