Archive:Poplar/Cicadas
From Bugwoodwiki
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From: Ostry, Michael E.; Wilson, Louis F.; McNabb, Harold S., Jr.; Moore, Lincoln M. 1988. A guide to insect, disease, and animal pests of poplars. Agric. Handb. 677. Washington, DC: U.S. Department of Agriculture. 118 p.
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Importance
Cicada adults cause no visible damage when they feed. Female cicadas injure shoots and branches of trees by laying eggs in slits on the bark. Terminal shoots may break over or die. Young trees, especially, may be heavily damaged, but older trees may only lose a few branches when infested. Dogday cicadas appear yearly; the periodical cicada is important at 17-year intervals in the North and 13-year intervals in the South.
Look For:
• Broken over or dead branch tips.
• Slits up to 3 inches long on the newest growth or at the juncture of a broken or dead branch tip, with fibrous material protruding from the slits.
• Stocky green to black boat-shaped insects 1 to 2 inches long on the trees. Males emit a high-pitched whine that may help you locate them.
Biology
Cicadas live from 2 to 17 years, mostly as nymphs underground, during which time they feed on roots. When mature, normally in April or May, the nymphs emerge from the soil at night and move to nearby trees to moult to the adult stage. The females lay eggs in the shoots of trees and shrubs; when the nymphs emerge, they drop to the ground to seek suitable roots on which to feed. Adults may live 5 to 6 weeks.
Monitoring
Inspect whips or young plantings in early summer for shoot injury. Listen for the whine of the males, which will be incessant when insects are abundant.
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| Egg slit made by cicada. |
 Photo by Jim Occi, BugPics, Bugwood.org |
Control
• In nurseries, prune and destroy shoots with eggs.
• Chemical control is usually impractical.
