White Pine Aphid
Host: White pine
Evidence: Look on the bark of tree trunks and branches for black aphids with a central white stripe, white spots on the sides and long, stiff hairs on the body. During the winter, examine needles for rows of black eggs. Honeydew, sooty mold, yellow jackets and ants (a) may be seen on twigs and branches. Look for branch flagging and discoloration of needles (b).
Life Cycle: Like many aphids, the white pine aphid has several generations and life forms each year. Winter is spent as black eggs on needles. These eggs are laid end to end in rows of 5 to 25. Eggs hatch in spring to yield the first of several generations of wingless females. In the fall, both winged males and females are produced. Mating occurs and new overwintering eggs are laid.
Management: Small trees may be killed by the white pine aphid, while branch dieback and discolored needles are common in larger trees that are infested. Needles on which eggs are found can be removed in the winter, or, if present in large numbers, eggs can be destroyed with dormant oils.
Figure a: E. Bradford Walker, Vermont Department of Forests, Parks and Recreation, Waterbury, VT.
Drooz, A.T. 1985. Insects of Eastern Forests. USDA Forest Service Miscellaneous Publication 1426. p 78;
Johnson, W.T. and Lyon, H.H. 1991. Insects That Feed on Trees and Shrubs. 2nd edition. Cornell University Press. p 84-85;
Rose, A.H. and Lindquist, O.H. 1999. Insects of Eastern Pines. Canadian Forest Service Publication 1313. p 37.