Cicadas rarely do any damage to garden plants. On occasions they may cause dieback of susceptible young plants such as fruit trees.
Identify the problem
Cicadas are common insects in gardens and parks. They are well known for their distinctive song in summer and autumn. There are several species in New Zealand but the most common is the Chorus Cicada shown.
Cicada nymphs live in the soil and suck sap from the roots of trees and shrubs; most plants seem little affected by this. When fully grown the nymphs grow a skin and leave the soil, climb a trunk or stem and emerge from their nymphal skin as adult cicadas leaving the skin attached to the trunk or stem.
Most damage is done when mated females lay eggs inside the young twigs of young trees or shrubs. A characteristic herringbone pattern may be seen along the twigs.
Did You Know
- Male cicadas use ribbed membranes (tymbals) on each side of the base of the abdomen to produce sound. Each tymbal is attached to a powerful muscle. As the muscle contracts it buckles the tymbal, much as when the domed lid of a jar is first unsealed, causing a pulse of sound. Then the tymbal pops back into shape. This is rapidly repeated to cause the distinctive cicada call.
- Cicadas are in the superfamily Cicadoidea, in the order Hemiptera (true bugs).