A “Double Brood” of Cicadas is coming in April, a Phenomenon which occurs every 221 years.

Billions of Cicadas. The last time this double brood event occurred, Thomas Jefferson was President. The next co-emergence of these broods won’t happen for another 221 years in the year 2245.

“When the soil temperature about eight inches down gets to be about 64 degrees, they’re going to start coming up,” explained Dr. Clyde Sorenson, Professor of Entomology and Plant Pathology at North Carolina State University. “They’re just waiting right now,” Sorenson added.

According to ABC, “The males are the ones that are making all the racket,” Sorenson said. “The predominant species sounds like he’s screaming ‘pharaoh’. It’s really high at a really high pitch. So, they say ‘pharaoh’ over and over and over about four hours a day until the right lady comes by.”

Sorenson said three species surface every 17 years, the other four species surface every 13 years. But, once every 221 years, their emergence overlaps, and two broods come out at the same. It’s an event expected to happen this spring across the Southeast and Midwest.

The blue map dots denote Brood XIII cicadas and the red dots are areas where Brood XIX has emerged in the past. These areas will likely have periodical cicadas in 2024. NBC.com

While cicada’s mating call may be loud, they are harmless to humans. They don’t sting or bite and are not poisonous. Cicadas may be damaging to young trees, though, if female cicadas lay their eggs in one. To better protect a tree, the EPA suggests covering it with mesh or netting with 1/4-inch holes or smaller. You can also wrap the branches in cheesecloth to keep cicadas away but they aren’t harmful to any flowers or fruit, they only consume sap to stay alive. Pesticides do not work on cicadas.