After 17 long years underground a brood of periodical cicadas will emerge in several east coast states. After they come out they have a mere four to six weeks to live. This is the first time after 2003 the brood known as brood IX will emerge. Some cicada species emerge annually, others mature underground for 13 or 17 years. The life cycle of cicada is a mystery of nature. The reason for such a long time to mature is still unknown.
Cicadas are harmless insects. Male cicadas sing out to silent females, using vibrating membranes on the sides of their abdomen. They are considered as the loudest insects on Earth. Tree growers and orchard and vineyard managers must be careful about the emergence of the swarms. The female cicadas lay hundreds of their small eggs in twigs and branches. This causes the branch or vine to split and wither. Trees weighed down with eggs can also die. However, their emergence naturally turns over soil and prunes trees, increasing flowers and fruits in later years.