Life cycle (Green apple aphid)

• Overwintered eggs on the bark of apple trees hatch in April, rather later than those of the apple grass aphid or the rosy apple aphid.
• The nymphs feed on the undersides of the leaves mainly in the tips of young shoots. Winged aphids develop in June and throughout the summer.
• The winged aphids migrate to other apple trees and these are largely responsible for the colonies that develop in extension shoots in summer. Wingless sexuals form in the autumn and eggs are laid on the bark of young shoots, often in considerable numbers.
• Colonies are usually attended by the common black ant Lasius niger, which feeds on the honeydew produced by the aphids but also defend the colonies from attack by natural enemies.