University of Illinois Extension
University of Illinois Extension - Selecting Trees for Your Home
Pine Bark Adelgid
Pineus strobi
Pine bark adelgid on white pine
Severity: 3 out of 5
Frequency: 1 out of 5
Symptoms: Light infestations do not do much to the tree. However persistent, severely heavy yearly attacks can cause twig death, some stunting, and possible death of the trees. The adelgids produce a wax while feeding. The wax is a protective cover that resembles wool, making them look like wooly aphids to which they are related. Under this waxy wool, the adelgid is teardrop shaped and black in color.
Cycle: After overwintering on the tree, reproduction occurs in the spring. At least five generations are produced per year. Winged adults can be produced which fly to spruce for additional reproduction; however, this does not appear to occur in the Midwest.
Management: Insecticides can be used to control these insects. Apply in May or later when adelgids are present. In the spring, applya spreader sticker with theinsecticide.
Associated trees: