What cicada broods appear in Illinois and where? –NBC Chicago

The historic cicada emergence of 2024 will see two broods of cicadas emerge this spring, and while some sightings have already been reported, how can you know which brood you’re seeing?

Cicadas have already started showing up in the Chicago area and parts of Illinois, but where you live will determine which brood you see — unless you’re in a certain part of Illinois where both broods can emerge at the same time.

“This is the year for Illinois,” cicada expert Catherine Dana, with the Illinois Natural History Survey, told NBC Chicago. “There will be crickets popping up all over the state.”

The two emerging broods are Brood XIII and Brood XIX, which have not emerged simultaneously in 221 years.

For the Chicago region, Brood

The Northern Illinois Brood itself is huge, with a reputation for the “largest emergence of crickets anywhere,” according to the University of Illinois.

Meanwhile, Brood XIX, or the Great Southern Brood cicadas, have a more widespread population, covering parts of Missouri, Illinois, Louisiana, North Carolina, Virginia and Maryland.

“Brood “Although 13-year-old cicadas are generally thought to have a southern distribution, the northernmost known find of this brood is in Chebanse, Illinois, approximately 75 miles from Chicago’s Loop.”

In most of Illinois and the Chicago area, at least one of the two broods is likely to occur, but in a small part of the state, both could occur at the same time and in the same place.

“Somewhere around central Illinois, probably like around Springfield, some researchers predict we’ll see some overlap between these two … different broods,” Dana said. “It won’t be a large area, but there will probably be some mating between these two broods, which will be very exciting.”

Here’s a map of what to expect in Illinois, according to data from the USDA Forest Service.

The rise has started earlier than average in Illinois, but for those wondering when the region could see swarms of crickets and the destructive noises that have prompted 911 calls in some states, that moment has yet to come.

Peak attendance for the Chicago area is expected to reach mid-May, according to experts at the Insect Asylum.

Sightings have been reported so far, but there are many factors that will determine when crickets will emerge en masse.

Cicadas usually appear as the ground begins to warm in spring and early summer, i.e. from mid to late May and into June.

“The periodical cicadas have been on the rise for the past week and a half,” Stephanie Adams, a plant pathologist at Morton Arboretum in Lisle, said Tuesday of Brood XIII, which will soon spread throughout the Chicago area. “We found them both here in our landscape and also in our eastern forests.”

According to Adams, the emergence of the first cicadas is about two weeks ahead of the historical average. However, it will remain sporadic as soil temperature, mulch and turf all impact crickets differently. For example, the ground is warmer near pavement, so the crickets in those areas are expected to emerge more quickly.

The ideal soil temperature for crickets is 64 degrees, but an increase in humidity can also play a role, reports the Insect Asylum.

Cicadas have a lifespan of about four weeks, meaning emergence will last until at least mid-June.

“Research shows that the specific night the periodic cicadas appear depends on soil temperature,” according to a release from the National Weather Service. “Young cicadas, or nymphs, emerge after a rain when the soil temperature at 8 inches of depth is above about 64°F.”