The big green bugs that make a deafening sound are back. Cicadas have popped out of the ground early this year and are starting to show up in Ohio and other parts of the Midwest, as well as the South and East Coast. First you see their skin. Then you hear their call. >> Swarms of cicadas expected soon in Southeast It's the unmistakable sound, and evidence the cicadas are back. 'I think they're really gross,' said Ashley Gilbert of Kettering, Ohio. 'They're a little scary, kind of prehistoric looking so they're a little startling,' said Melissa Todd of Riverside, Ohio. The fragile brown casings could be from Brood X – some of these 17-year cicadas reportedly are arriving four years early – or the annual dog-days-of summer cicadas that have arrived several weeks ahead of time. >> Read more trending news According to the Gardener's Network, Brood X cicadas span the following states: Georgia, North Carolina, Ohio, Pennsylvania, Tennessee, New York, Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, Virginia and West Virginia. Whichever kind they are, cicadas don't bite and don't cause much harm to trees. Their loud sounds and startling movements is all most will have to deal with. – The Cox Media Group National Content Desk contributed to this report.