Winged females develop during some of the generations. These winged aphids fly to other parts of the same tree or to different trees. In late fall, winged male and wingless female aphids are produced. They mate and the wingless females lay fertilized overwintering eggs on the tree. Twenty to 30 successive aphid generations may occur during the year depending upon the season.
Aphids are present in orchards whenever pecans are in leaf.
The black pecan aphid is normally most numerous from late July through October, although they may occur in significant numbers as early as late April. When sampling for black pecan aphids, check all the compound leaves on 10 terminals per tree on at least 10 trees per orchard. Sample susceptible cultivars such as Schley, Sumner or Gloria Grande. It is very important that sample size be large enough to detect small population increases to avoid excessive damage.