Billions of cicadas to ascend in Ohio, New York, Pennsylvania

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The insects, which have spent the rest of their lives underground, only live above ground for about six weeks. The adults, the ones that make all the noise, only ascend above ground to reproduce.

Males use the harsh sound to look for females so they can mate in that brief time. The sound can reach over 90 decibels in some instances; that's about the same volume as a lawn mower.

The female cicadas will lay eggs in a tree, and after the eggs hatch, the newborn cicadas -- called nymphs -- will bury themselves in the ground, where they'll develop for 17 years.

According to The Washington Post, female cicadas can lay up to 400 eggs each, across 40 to 50 sites.

During the upcoming mating season, there could be as many as 1.5 million cicadas per acre in some places.

The noise, which is mostly a daytime phenomenon, will probably last until mid- to late June, by which time most of the cicadas will probably die, according to Gaye Williams, a Maryland Department of Agriculture entomologist. Williams said predicting exactly when the emergence will end is tough because it depends on many variables, including temperature, moisture and humidity.

The good news is that cicadas can't chew, so they don't devour plants and trees. Plus, they don't bite or sting.

But if you live in Ohio, New York, Pennsylvania and other neighboring states, now might be the time to invest in some ear plugs.