Table: Diagnosis and Control of Balsam twig aphid
Pest Identification	Host Plants	Damage Symptoms
Balsam twig aphid Mindarus abietinus family Aphididae	Balsam and Fraser fir, occasionally on spruces.	Slight curling and stunting of previous years' needles. Shoots may appear twisted and silvery. Most of the needle curling straightens out once needles mature. Injury is cosmetic and does not significantly damage trees.
Monitoring	Control Options	Pesticides
First generation aphids are present prior to budbreak. Adults and their cast skins can be found on the stem and older needles within 1-2 inches of developing buds. Scout aphids by beating the outer 10 inches of midcrown foliage over a small black cloth. Sample 2 branches, one on each side of a tree. If you find 2 or more aphids and the tree was infested the previous year, control may be warranted.	In urban landscapes control is seldom warranted, natural enemies and weather generally restrict the level of damage. Physical: On individual landscape trees, a strong stream of water from a hose can kill many aphids. Shearing can remove heavily damaged shoots. Spraying trees when needles begin to curl will probably NOT prevent damage from occurring. Chemical: Apply a registered systemic insecticide just before budbreak if the tree has suffered annual infestations that have caused permanent needle curling.	Acephate
Description and Life History
Description: Green aphids may be either winged or wingless. They are most often covered with a white powdery wax. Honeydew may be present. Newly hatched nymphs are yellow and often rest on the underside of the previous years' needles. Life history: Overwintering eggs hatch in early spring and quickly mature into stages that feed on developing needles. Several overlapping generations produce both winged and wingless aphids by mid-June. By early July, the non-feeding adults have mated and laid eggs on stems and at bases of needles.

Back to Balsam twig aphid slides

Back to Insect Pests of Conifers