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Outdoor Insects
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return to Outdoor Insects -
Cicadas
-by Dennis M. Ferraro Extension Educator Douglas/Sarpy Extension
Unit
The Periodical cicadas are one of the longest living (13 to 17
years) insects on earth. After spending 17 years underground in a
dark, moist, quiet world, they will emerge to the surface of the
ground. When they emerge, it will be by the thousands (up to one
million per acre). This will be a spectacle worth photographing.
The cicada nymphs dig their way out of the soil during late May and
June and climb up tree trunks, posts and poles. The outer shell of
the nymph splits along the middle of the back, and the winged adult
laboriously emerges in about an hour.
Each adult may live for 5 or 6 weeks. During that time the males and
females mate and the females lay the eggs that are the start of the
next generation. Eggs are laid into the small twigs of trees and
shrubs. This causes moderate twig dieback and some disfigurement
("flagging") of forest and woodland trees, but no long-term
consequences. The eggs hatch after 6 to 7 weeks and the newly
hatched nymphs fall to the ground, burrow until they find a suitable
tree root, and begin the feeding and waiting period that will last
until the year 2015.
Periodical cicadas are well-known for the size of the mass emergence
and the incredible noise they make. The males "sing" with a loud
buzzing or drumming sound that goes on all day long. With
populations that can reach up to a million per acre, the sound can
be as deafening as it is incessant. Only male cicadas sing. The
sound is produced by vibrating two shell-like drums located along
the sides of the abdomen. Strong muscles vibrate the drum membranes
several times per second. The resulting high-pitches, rapid clicks
are resonated through air sacs and other structures to control sound
volume and quality. The upward angles of the wings form a
megaphone-like chamber that further controls the sound.
The cicadas will cover everything in the areas they emerge. In
Nebraska, they will begin emerging from the ground in the counties
that border the Missouri River, or areas containing eastern hardwood
forest.
Besides the Periodical cicadas, Nebraska has several types of
cicadas. The most common is the Annual or "Dogday" cicada, which is
the type that is heard most often every year.
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