Both males and females were wingless. A few days after mating, the female laid a single, long, oval, cinnamon-colored egg almost as large as her body. The egg was laid in the crevices of bark. With the disappearance of elm trees, the woolly apple aphid lives primarily on apple trees throughout the year. Each group of aphids, small or large, is termed a colony.
Aphids are present year-round on the roots.
Females in the aerial colonies may give birth to crawlers at any time in spring, summer, or fall. Newborn nymphs are very important in the distribution of woolly apple aphid. They spread either through some mechanical agent or directly by crawling. Birds and insects can also transport aphids. Crawlers are generally more abundant in spring and fall.