An entomologist at the College of Mount Saint Joseph says that when cicadas emerge this year, he won't be able to hear planes from the Cincinnati/Northern Kentucky Airport fly overhead. Among the several broods of periodical cicadas, this year's will be one of the largest. Entomologist Gene Kritsky says the screech of (b) billions of the shrimp-sized pests are expected by late May in parts of at least ten states from Georgia to Indiana. Experts say the noise is annoying, and when the cicadas die the rotting carcasses can foul the air for a week. Their huge numbers mean birds can eat their fill and leave enough to breed. The nymphs will crawl underground to suck on tree roots for 17 years -- then emerge in the year 2021. They're annoying but don't do much damage. In fact, the carcasses fertilize lawns.