Cicadas, specifically their nymph stage, burrow underground to depths of about 2.5 meters (8 feet) where they live for most of their lives feeding on xylem sap from roots
. Periodical cicadas typically live underground usually within about 2 feet (61 cm) of the surface, feeding on plant root juices, and their emergence is triggered when the soil temperature at 12-18 inches deep reaches around 64-65°F (17-19.5°C)
. The nymphs dig chambers near roots and use strong front legs for excavating. They also preemptively dig holes to the surface, which can be about the size of a dime, and sometimes form small soil "chimneys" over their burrows when the soil is moist
. In summary:
- Cicada nymphs burrow up to about 2.5 meters (8 feet) deep underground
- Periodical cicadas generally live within about 2 feet (61 cm) of the surface and emerge when soil temperatures at 12-18 inches depth reach about 64°F
- Burrows and chambers are dug near roots where they feed and develop
This depth range allows cicadas to stay protected underground for years (from 2 up to 17 years depending on species) before emerging as adults
