Pine bark adelgid

You will see white, fluffy cottony masses on pine bark, particularly on younger trees and in branch crotches. These masses contain adelgid colonies. Heavy infestations cause yellowing needles and twig dieback. Bark becomes sunken and bark-splitting may occur. The pest overwinters on bark and produces multiple generations. Eastern white pine and other pine species are susceptible.

Prune infested branches when populations are localized to young trees. Horticultural oil sprays target adelgids in late fall or early spring before new growth. Time applications for dormant season to maximize contact. Avoid unnecessary pruning that stresses trees. Natural enemies including small parasitic wasps and beetles attack adelgids. Maintain tree vigor through proper care.