One thing that is important to determine is whether any of the off-schedule populations (especially the 4-year early and 4-year late ones) are large enough to persist and lay eggs. The big question is will they establish a new population? Please send photos of cicadas laying eggs. And if egg laying is extensive enough to damage branches, please send photos of that as well!
Some Brood XIII cicadas are emerging 4 years early, particularly in the Chicago area in 2020. Blue in the map below:
Periodical cicada Brood XIII (13) will emerge in the spring of 2024 in Iowa, Wisconsin, Illinois, Indiana, and possibly Michigan. The last time this brood emerged was in 2007.
Special note: Brood XIX (19) will also emerge in 2024.
What, when, where, and why:
Millions of these:
- Cicada insects with a 17-year life cycle.
- Some people call them “locusts” but they’re really cicadas.
- Which species: All three 17-year species, Magicicada septendecim, Magicicada cassini and Magicicada septendecula. How to tell the difference between the species.
- NOT the green ones that arrive annually.
When: Typically beginning in mid-May and ending in late June. These cicadas will begin to emerge approximately when the soil 8″ beneath the ground reaches 64 degrees Fahrenheit. A nice, warm rain will often trigger an emergence.
Other tips: these cicadas will emerge after the trees have grown leaves, and, by my own observation, around the same time Iris flowers bloom.
- Illinois places: Belvidere, Brookfield, Channahon, Chicago, Des Plaines River Trail, Downers Grove, Elmhurst, Flossmoor, Geneva, Glen Ellyn, Highland Park, Hinsdale , Homewood, La Grange , Lagrange Woods, Lake Forest, Lansing, Lincolnshire, Lisle, Lombard, MacArthur Woods Forest Preserve, Marseilles, McHenry, McKinley Woods, Morton Arboretum, Naperville, Northbrook, Ogden, Ottawa, Palos Heights, River Forest , River Grove, Romeoville, Schiller Park, Thornton, Vernon Hills, Villa Park, Weaton, Western Springs, Westmont, Wonder Lake, and more.
- Illinois counties: Bureau, Carroll, Cass, Cook, DuPage, Fulton, Grundy, Henderson, Henry, Jo Daviess, Kankakee, Lake, LaSalle, Livingston, Logan, Marshall, Mason, McHenry, McLean, Menard, Peoria, Putnam, Sangamon, Stark, Tazewell, Whiteside, Will, Winnebago, Woodford.
- Iowa places: Atalissa, Solon, and more.
- Iowa counties: Benton, Black Hawk, Bremer, Cedar, Dubuque, Henry, Iowa, Johnson, Jones, Linn, Louisa, Muscatine, Scott, Tama.
- Wisconsin places: Aurora University, Big Foot Beach State Park, Lake Geneva, Moraine Nature Preserve, and more.
- Wisconsin counties: Crawford, Grant, Green. Rock, Walworth.
- Indiana places: Crown Point, Portage, Purdue-North Central, Valparaiso, and more.
- Indiana counties: LaPorte, Porter, Lake.
- Michigan: According to Magicicada.org, Magicicada have been found along the border of Michigan and Indiana.
More Location Tips:
- County data is from the Cicada Central Periodical Cicada Record Database. Cities come from May 2007 reports and June 2007 reports.
- Not sure? Ask someone in your community who lived there 17 years ago.
Why: Why do they stay underground for 17-years? The prevailing research suggests they’ve evolved a long, 17-year lifecycle to avoid predators that can sync up with their lifecycle & emergence. Why are there so many?! Research suggests that their huge numbers allow them to overwhelm predators, so enough of them will live on to breed and perpetuate the brood.
More facts and fun:
- Use the correct image when talking about these cicadas.
- Use the Periodical Cicada Emergence Checklist for the Maximum Magicicada Experience.
- All cicada questions that are frequently asked.
- A video to help you tell the difference between the species.
- The 17 Most Interesting Periodical cicada facts.