Two distinct broods of cicadas are set to surface from under the ground at the same time across Indiana and Illinois, according to Cicada Safari. Both broods – Brood XIII and Brood XIX – are estimated to emerge when temperatures reach 64 degrees Fahrenheit eight inches below the ground and in response to warm rainfall usually from mid-May to late June.
Brood XIII, sometimes called the Northern Illinois Brood, is set to appear in Lake, LaPorte and Porter counties. It has a smaller range, primarily in eastern Iowa, northern Illinois, southern Wisconsin and near Lake Michigan in Indiana. The brood has a 17-year lifespan and last emerged in 2007.
Meanwhile, Brood XIX, the 13-year cicada, will make its presence known in eight western counties stretching from Posey and Warrick in the south to Jasper and Newton in the north. Brood XIX, also known as the Great Southern Brood, has a significant range, spanning across several southern and midwestern states. It was last sighted in 2011.
According to Axios, the two broods are emerging simultaneously for the first time in 221 years, and Indiana and Illinois will be the only states observing this phenomenon geographically. While there is no direct overlap between the broods, Springfield, Illinois, is where the two groups will be closest.
According to The Purdue Department of Entomology, the cicadas are harmless to people, animals and property, and it recommends tree owners cover their young plants of three to four years with mesh fabric for the month-long period.
