Adult cicadas suck juice out of the roots and stems of trees for sustenance. These insects have a specialized feeding tube, similar to a beak, that penetrates the bark of trees. Cicadas can feed for hours at a time during summer months in order to gain nutrition and regulate body temperature.
A cicada's mandible works by wiggling back and forth before penetrating the xylem, or bark, of a tree. The insects raise up on their forelegs to feed instead of getting closer to the branch, stem or root of the plant. When not feeding, the mandible rests between the legs. The juice from the trees provides water, minerals and some carbohydrates.
Young cicadas burrow into the ground and suck on juices of softer roots until they are adults. Cicadas can spend many years underground before emerging as adults to feed on main portions of trees. Some of these insects spend between 13 and 17 years underground before emerging.
Cicadas serve an important role in their ecosystem. Larger insects, bats, frogs, large spiders, praying mantises and birds feed off the animals. When millions of cicadas emerge from the ground after 13 or 17 years, they provide plentiful food for animals that predate upon them.