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Brood X Periodical Cicadas Hit PEAK 2021 Emergence

Photo Credit: Pennsylvania Department of Conservation and Natural Resources – Forestry,

Brood X periodical cicadas are hitting PEAK emergence in many parts of Maryland. This means millions of fully-grown winged adults are flying and blundering into things (and us), “singing” as loud as they can, and starting to mate.

Photo Credit: Eric R. Day, Virginia Polytechnic Institute and State University,

What’s that loud buzzing you hear? It’s the sound of male cicadas earnestly belting out their love songs! In some areas, this ensemble chorus is being measured at 100 decibels – that’s louder than a lawnmower or low-flying jet!

Photo Credit: Pennsylvania Department of Conservation and Natural Resources – Forestry,

What can we expect next? Mated female cicadas are laying eggs in small twigs of woody plants and mature trees. This will cause ‘flagging’ or browning of branch ends. Later this summer, they can be pruned out.

Photo Credit: Lacy L. Hyche, Auburn University,

Spent adults are already dying and joining the piles of brown nymphal exoskeletons they shed earlier this spring. Adult periodical cicadas are expected to be gone by the end of June.  

PRO TIP: Try adding cicada carcasses and exoskeletons to your compost to pile!

Photo Credit: Maryland Department of Agriculture

In late July-early August, after their parents are gone, tiny cicada nymphs will hatch, fall from the trees, and quickly burrow underground to harmlessly feed on roots. They will quietly live here for the next 17 years.

Photo Credit: Maryland Department of Agriculture

So take a big sigh of relief or sadness. We are more than halfway through the 2021 Big Brood X emergence!

Try to appreciate the fascinating, mysterious life cycle of these unique insects that are found nowhere else on Earth. Soon enough they will be gone, not to be seen again until 2038.

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Contact Information

If you have any questions, need additional information or would like to arrange an interview, please contact:
Jessica Hackett
Director of Communications
Telephone: 410-841-5888