Cicadas are insects known for their distinctive sounds and remarkable life cycles, which often culminate in large-scale emergences. These events provide an opportunity to observe creatures that spend most of their lives hidden underground. Understanding their appearance offers insight into their biology and environmental cues.
Annual Cicada Emergence
Georgia experiences annual cicada emergences each summer, featuring “dog-day” cicadas. These cicadas typically appear from late June through early September. Different generations emerge each year, ensuring a consistent presence. Annual cicadas are generally larger than their periodical counterparts, recognized by their green bodies and black eyes.
Periodical Cicada Broods
Beyond annual visitors, Georgia is home to periodical cicadas (Magicicada), which emerge on synchronized cycles of either 13 or 17 years. These large-scale emergences are less frequent but more dramatic due to the sheer number of insects appearing simultaneously. Periodical cicadas are visually distinct with black bodies, bright red eyes, and clear wings often tinted orange.
One significant group, Brood XIX, also known as “The Great Southern Brood,” is a 13-year cicada that last emerged across Georgia in 2024. This brood is the largest periodical cicada emergence by geographic extent in North America, affecting counties like Fulton, Cobb, and Troup. Its next emergence in Georgia is expected in 2037.
Another notable periodical brood, Brood XIV, is emerging in Georgia in 2025. This 17-year cicada brood was last seen in 2008 and is expected to return around 2041 or 2042. Brood XIV’s presence is primarily in northern counties such as Fannin, Lumpkin, Rabun, and Union. Brood X, another 17-year cicada, last appeared in a few northern Georgia counties in 2021 and is projected to re-emerge in 2038.
Environmental Factors for Emergence
The timing of periodical cicada emergence is largely governed by soil temperature. Cicada nymphs typically emerge when the soil temperature reaches approximately 64 degrees Fahrenheit (18 degrees Celsius) at a depth of about eight inches. This temperature signals suitable conditions for their development and reproduction.
Warm rainfall can also trigger a more intense emergence once soil temperature is near the optimal range. These factors ensure millions of cicadas emerge simultaneously, a strategy that helps them overwhelm predators and ensures enough individuals survive to reproduce.
What to Expect During an Emergence
When a large periodical cicada brood emerges, the experience is distinctive due to the sheer numbers. Millions of cicadas can appear per acre. One noticeable aspect is the sound, as male cicadas produce extremely loud buzzing or singing to attract mates, which can be as noisy as a jackhammer.
The landscape during an emergence is characterized by adult cicadas and their discarded exoskeletons, or shed skins, left by transforming nymphs. Cicadas are harmless to humans and pets; they do not bite, sting, or pose a threat. They pose minimal threat to mature plants, though very young trees might benefit from netting for protection. Adult cicadas typically live for about four to six weeks above ground, focusing on mating and laying eggs before their life cycle concludes.