Periodical cicadas belonging to Brood X emerged in parts of western Ohio and most of Indiana in May and June of 2004. The mass emergence started on the evening of May 12, a week earlier than previous emergences, with some areas reporting over 300 cicadas emerging per square meter. Mapping of the eastern Cincinnati boundary of Brood X found evidence that some Brood XIV cicadas, expected to emerge in 2008, emerged four years early. Housing developments built in the 1990s and devoid of emerging cicadas attracted cicadas from areas over a quarter of a mile away. These dispersing cicadas formed chorusing centers that reached 96 dB in intensity and resulted in heavy oviposition in trees planted after the previous Brood X emergence in 1987.