Unfortunately, the ones appearing as adults in the next few years can overwhelm your cooling towers, evaporative condensers, and air-handling units. They emerge as adults in 17-year intervals in large and generally nonoverlapping geographic regions of the northeastern United States.
Because of this separation in time and place, these species are called periodical cicadas, and their various widespread populations are called broods. A total of a dozen such broods are recognized, according to Dr. Thomas E. Moore, Museum of Zoology, University of Michigan, Ann Arbor, Mich., who provided all of the cicada distribution and biological information for this article.