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Hemlock Woolly Adelgid

Hamilton County Distribution


  • Insects
  • Adults are dark reddish-brown to purplish-black in color
  • Adults produce wool-like wax filaments (ovisacs) that contain eggs


  • Hemlock woolly adelgid consumes sap and nutrients from hemlock foliage, preventing tree growth
  • Signs and symptoms of infestation include white, woolly ovisacs on branches, foliage, and bark, defoliation, and twig dieback
  • Tree death occurs in 4-10 years
  • Host trees include Eastern and Carolina hemlocks
  • This invader spread by wind, birds, animals, and humans


  • Quarantine zones
  • Remove and chip infested trees
  • Insecticides
  • Biocontrol
  • Slow the spread and don’t move firewood

  • HWA1Small
  • HWA2Small
  • HWA3Small
  • HWA4Small
  • HWA5Small
  • HWA6Small
  • HWA7Small

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