Red-eyed cicadas to emerge from the ground in SC soon. Here’s when, where & if they’re harmful

Sometime within the next month a new brood of cicadas will emerge from the ground in 14 eastern states including South Carolina.

But don’t expect it to be anything like last year when many South Carolinians could just step into their backyards and see — and hear — a swarming mass of insects.

Brood XIV, which comes out every 17 years, likely will only be in the northwestern tip of Oconee County, said Eric Benson, Clemson University professor emeritus and extension entomologist.

“Most of the activity will probably be in Tennessee and Kentucky, so this brood will not be seen in most of South Carolina,” he said.

Last year, the Great Southern Brood of cicadas emerged after 13 years, crawling up trees, molting and leaving their outer skins hanging. Once the adults are done mating, the females lay their eggs in tree limbs, which split, turn brown and die. Cicadas also lay eggs in bushes, which can cause them to die as well.

But it was the sound that caught most people’s attention and turned the invasion into a lesson for school children.

The brood sounded like a lawnmower thrumming through the night. Cicadas are among the loudest animals in the world, despite their size.

The sound is actually a click but it’s made so rapidly it sounds like a hum.

It’s meaning? It’s the males looking for a mate.

There are seven species of periodical cicadas, four with 13-year life cycles and three with 17-year cycles, according to the University of Connecticut’s cicada information website.

Brood XIV is among the largest of all 17-year cicadas.

They live underground, sucking root fluids and growing from the size of a small ant to nearly the size of an adult, the University of Connecticut said. Scientists don’t know how the creatures keep track of the years, but at some point their eyes become red and they begin digging tunnels to get out.

Soil temperature determines when they crawl out, usually after sunset.

“What makes periodical cicadas unusual is the combination of long life cycles, mass emergences, and periodicity, such that the vast majority of individuals in a population emerge on the same schedule and after a set number of years, UConn said.

It’s expected the cycle from emergence to the old generation dying off to the new going back underground will be about six weeks.

Benson said cicadas are an important piece of the ecosystem and a sign of health. They’re also a source of food for a variety of animals and their carcasses release nutrients into the soil.

They don’t carry disease and are not harmful to humans or pets.

Besides South Carolina, states expecting Brood XIV this year include Georgia, Kentucky, Maryland, Massachusetts, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia and West Virginia.

This story was originally published March 13, 2025 at 6:00 AM.