Cicadas bring the noise!

by | May 8, 2013

Shed cicada nymphal skin; Image: Herbert A. “Joe” Pase III, Texas Forest Service,

You may have heard on the news recently that this year marks the emergence of a brood of 17-year cicadas across the East Coast — Brood II to be exact. And North Carolinians are already beginning to see these insects emerging. This year’s emergence is expected to be in the northern piedmont region.

Periodical cicada adult; Image: John Ghent, U.S. Forest Service,

North Carolina is home to many species of cicadas, including those that are periodic and those that yearly fill our summer evenings with their calls. Periodical cicadas have black and orange bodies and red eyes, which distinguishes them from the common dog-day cicadas. Cicadas are not poisonous nor do they bite. In fact, they provide food for many animals and even people, in some cultures.

Female cicadas lay their eggs in small slits they create on the tips of tree branches, commonly oaks. These branch tips may eventually die and fall to the ground. When the eggs hatch, the nymphs burrow into the soil where they feed on tree roots for up to 17 years, depending on the species and brood. When conditions are right for them to complete their life cycle, they emerge from the ground and molt into adults. The adults only live for a few weeks and produce many calls associated with mating. When periodical cicadas emerge en masse, the sound of their calls can be deafening.

Dying branch tips as a result of periodical cicadas; Image: Linda Haugen, U.S. Forest Service,

Periodical cicadas are not considered a forest pest, though females laying eggs can cause the tips of tree branches to die. In heavily affected trees, there may be many dead branch tips. The damage causes little long-term impact to large trees. Smaller ornamental and fruit trees can suffer losses of branches due to the egg-laying habits of periodical cicadas, but insecticidal control is often ineffective and is not recommended. If populations of the periodical cicadas are large enough, homeowners concerned about small trees can cover the trees completely with netting until the adult cicadas are gone.

It doesn’t happen very often, so sit back and enjoy the upcoming cacophony!  For more information about the 17-year cicada, visit Cicada Mania.