Pine Bark Adelgid
Pineus strobi
Key Features

  • White Wooly Bands on Trunk
  • Wooly Patches on Branches
  • Wooly Tufts on Twigs
White wooly bands on trunk
White wooly bands on trunk
Individuals on branches
Individuals on branches
White spots on branches
White spots on branches
Symptoms

Trunks and or branches can be partly or completely covered in a white, wooly wax if tree is heavily infested. Twigs can also be covered. Lighter infested trees only have isolated spots on branches. These insects can slow the growth of newly planted white pines if the infestation is heavy enough to coat the trunk.

Pine bark adelgid on twig
Pine bark adelgid on twig
Biology

Adelgids winter as immature nymphs under strands of white wax. Adult females mature in late spring, and lay eggs on the trunk and twig in April. They can have several generations a year.

Management Recommendations

These native insects are normally controlled by a wide range of predators and parasites that feed on them. On small trees with a heavy infestation you can often get control by knocking the insects off the trunk and branches with a strong stream from a garden hose. If this does not work, you can then try an application of insecticidal soap or horticultural or neem oil. Other pesticides will kill the insect and the natural enemies.

Effective Pesticides

Active Ingredients include: Azadirachtin, Horticultural oil (Paraffinic or superior oil) , Insecticidal soap (Potassium salt of fatty acid), Neem oil