The long hot days of summer are filled with many familiar sounds; kids splashing in a pool, the sound of a bat hitting a ball and the often heard screeching song of a male cicada singing to attract a mate.
Cicadas are often called harvestflies or locusts. There are 166 species of cicadas found in the U.S. and Canada. Some of the best known species include the periodical cicadas and the dog-day cicadas.
Cicadas range in size from less than 1.0 inch too longer than 2.25 inch. They are rather robust insects with large bulging eyes and transparent wings that are held roof-like over their body. Most species are brownish but some are marked with orange, green black or white.
Female cicadas lay their eggs in slits that they cut in the bark of twigs, in the top of trees. When the eggs hatch the tiny nymphs fall to the ground and burrow into the soil. Some may burrow several feet deep. The nymphs resemble wingless adults but have their front legs greatly enlarged and developed for digging.
The life cycle of cicadas is quite lengthy. It ranges from four years in some species to as long as 17 years in periodical cicadas. Once fully developed the nymphs dig their way to the surface. They emerge from the soil at night and crawl up a tree trunk, shrub or other structure. Here they molt into adults. The old nymphal skin or "shell" as it is often called, is left hanging on tree or other structure, while the adult flies off to begin the next generation. Adults live only for about four to six weeks.
Adult cicadas feed by sucking sap from twigs and stems. Nymphs suck sap from roots. Feeding activity does not cause plant damage. However, the egg-laying activity of the female can damage and even kill small twigs in the top of trees.
Only male cicadas sing. The sound is produced by a complex, membranous organ, located at the base of their abdomen. Muscles attached to the organ vibrate it rapidly, producing the sound.