Brood X prepares to emerge

Photo Courtesy Missouri Department of Conservation 

The U.S. is buzzing with preparation for a new brood of 17-year cicada’s. 

This years brood will emerge covering more of the eastern half of the U.S. than any other brood.

Their emergence is based on soil temperatures. The brood will leave the soil once the soil temperature reaches 64 degrees Fahrenheit. 

The geographic reach of these cicadas was attributed to co-emergence of other broods and stragglers from other broods. 

Seventeen-year cicadas are a species known as a periodical cicadas. These species spend years in the soil as nymphs (young cicadas). 

Cicadas hatch and fall from trees in order to burrow up to 18 inches into the soil. 

According to The Scientific American this species has an internal clock that is a mystery to scientists. 

Close to exactly 17 years after burrowing the nymphs leave the ground as adult, abandoning their exoskeletons

Cicadas immediately perch in trees and begin making a buzzing noise which is used to attract a mate. 

Seventeen-year cicadas have several different types of calls, one to attract a mate, a courting call an alarm call.

Those cicadas that emerge around the same time are separated into broods. These broods can then be monitored to predict their next emergence from the soil.

Another type of periodical cicadas exists, 13-year cicadas which emerge every 13 years. There are only three broods of 13-year cicadas compared to the 12 broods of 17-year cicadas.

This year Nebraska will only have the common annual cicadas which resemble their periodic relatives do not spend years in the soil. 

Nebraska’s last visit from periodical cicada’s happened in 2015 with brood IV, who won’t make another appearance until 2032.