It was the first time in 221 years that two cicada species (chicks XIX and XIII) emerged from the ground at the same time, during Thomas Jefferson’s time as president, and it is not expected to happen again until 2244.
This insect, 1 to 2 inches long, has a sturdy body, bulging compound eyes, and membranous wings with a 3-inch wingspan.
But don’t worry. Cicadas are not harmful to humans, pets, home gardens or crops, the Environmental Protection Agency says.
In fact, they are a valuable food source for birds and mammals. Cicadas provide air to the lawn, improve water filtration into the ground, and add nutrients to the soil as they decompose.
Most species of cicadas occur annually, but in the United States there are two periodic cicada swarms that remain underground for 13 or 17 years.
“It’s rare for two members of different periods to emerge at the same time, because their periods are both prime numbers,” John Cooley, a cicada expert at UConn, told Live Science.
“A given 13 year old and 17 year old piece will only appear together once every 13 x 17 = 221 years.”
Reuters
Floyd Shockley, an entomologist at the Smithsonian Institution’s National Museum of Natural History in Washington, said Blued XIII cicadas appear every 17 years, mainly in northern Illinois, eastern Iowa, southern Wisconsin and far northwestern Indiana. It is said to be limited to a few counties.
Brood Widely distributed in the Carolinas, Tennessee, and Virginia. There are 15 states total, Shockley said.
Their lineage spans a combined 17 states.
Reuters
These two lineages overlap only in a small area of central Illinois, and occasionally in Indiana.
They are close enough that interbreeding can occur between conspecifics.
Female cicadas make cuts in small branches of trees and usually lay 20 to 30 eggs in each cut.
Females lay 400 to 600 eggs during their lifetime.
Eggs hatch in late July to early August.
The cicada then falls to the ground and quickly burrows underground.
If they die in large numbers, they can give off a foul odor.
They can’t lay eggs in their skin, Cooley told MassLive.
“This summer, some people will have the chance to witness a phenomenon rarer and perhaps even larger than Halley’s Comet,” Cooley said.
“It’s hard not to notice periodic cicadas, because they’re noisy, charismatic, active insects that come in millions and are everywhere,” Cooley said.
However, the EPA says cicadas can be dangerous to young trees because they lay eggs on small branches of trees and can harm the trees.
The agency advises covering mature seedlings with mesh or netting to prevent insects from entering.
Reuters and The Associated Press contributed to this report.
