Illinois Cicadas: How Long They Live, And When They’re Loudest

We knew it was coming, and based upon numerous reports over the last few days, "Cicada-Geddon" has begun in a few spots here in Illinois, with a lot more to follow.

If you were wondering what your yard is going to look like once the cicadas begin their emergence, those two tweets, especially the second one, should give you a pretty good idea of what will be happening throughout the state of Illinois within the next 10 or so days.

Not unlike when your relatives come to visit, the coming cicada emergence is going to turn into a "now that they're here, when will they leave" scenario.

So...when do the cicadas wrap things up and head back underground for us to get all worked up about in another 17 years?

The Cicadas Start Coming Out Of The Ground When The Soil Temperature Eight Inches Down Reaches 64 Degrees, And Several Parts Of The State Have Already Reached That Temperature

Obviously, based on the photos and videos, the soil temp in Western Springs is just right for the Northern Illinois Brood cicadas to emerge, and that will soon be the story statewide.

Remember, the Northern Illinois Brood is absolutely gigantic. The University of Illinois is calling the coming cicada emergence the largest emergence of cicadas anywhere, and this simultaneous emergence is the first one since 1803 and will not happen again until 2245. We're talking billions, if not a trillion, cicadas.

Here's An Expected Timeline For Cicada-Geddon 2024, Including When They Are Finally Gone

• Regardless of where you live in Illinois, things should roll out the same when it comes to cicada behavior during this once-in-a-lifetime event.
• Upon emerging, cicada nymphs will immediately look for ways to climb up trees or other objects, where they will then molt, leaving their shell or exoskeleton hanging there.

• The male cicadas will gather in trees where they'll start singing for a mate about 5 days after molting. This gets really, really loud. Even though the noise won't cause hearing loss, keep in mind that cicada-song can reach 90 to 100 decibels, which is similar to a lawnmower or motorcycle.
• After the mating ritual, the female cicadas will look for an area of woody plants, where they'll lay approximately 600 eggs each.
• About a month after emergence, the adult cicadas will start dying in huge numbers. Word has it that the piles of cicada corpses under trees will start to smell pretty rank, not unlike the scent of roadkill. The gardening community says that cicada bodies make an excellent fertilizer.

• About two months after the eggs are laid, they'll hatch. The newborn cicada nymphs will drop to the ground, do some feeding, and then dig themselves into the ground for their next appearance.
• We should be cicada-free (for the most part) by the time Independence Day rolls around on July 4th.