Cicada Emergence

May 21, 2024

The anticipated emergence of periodical cicadas will be here soon. Brood XIII, also known as the Northern Illinois Brood, will surface after 17 years, last seen in 2007, captivating us with one of the largest cicada emergences worldwide. Cicadas emerge annually in various parts of the eastern United States, with cycles repeating every 13 to 17 years. This year holds special significance as two broods are emerging simultaneously, a phenomenon not seen in 221 years.

Northern Illinois hosts both annual and periodical cicadas. Annual cicadas show up every year from July to September. Periodical cicadas have longer lifespans, spending 13 or 17 years underground before a brief 20-25 days as adults. They’re smaller than annual cicadas, maturing at 1.5” in length.

Chicago might see up to 1.3 million cicadas per acre in flood plains and 133,000 per acre in upload areas. Late summer may reveal some tree damage from egg-laying, but it’s natural pruning and won’t harm the tree’s health.

Vernon Hills Park District will not be covering trees due to the large number within our parks, residents may choose to cover their own trees. Avoid insecticides on trees as they’re generally ineffective and harmful to beneficial insects.

Don’t worry, cicadas don’t bite, harm humans, or our pets.

Appreciate this rare and natural phenomenon — it only lasts a few weeks!