The green apple aphid (Aphis pomi) is one of the most common aphid species in apple orchards. Both nymphs and adults feed on young leaves and shoots, reducing tree vigor and affecting shoot development. While moderate infestations (<5% leaf curling, <10% shoots infested) are often tolerated by healthy, mature trees, high populations can slow vegetative growth, contaminate fruit with honeydew, and reduce overall orchard performance, particularly in young plantings and nurseries.
Green apple aphid infestations can cause a range of symptoms, including:
Green apple aphid overwinters as small, shiny black eggs on apple trees, typically laid around buds, branch forks, and young twigs.
Eggs hatch shortly before bud break, when temperatures exceed 10°C. Wingless females colonize young shoots and reproduce rapidly without mating, allowing populations to build quickly during spring.
Several generations develop throughout the growing season, typically four to six generations in temperate climates. The first generation usually appears three to four weeks after egg hatch. Winged adults periodically disperse to nearby trees, establishing new colonies and increasing aphid populations throughout the orchard.
In autumn, sexual forms are produced, and females lay overwintering eggs on apple trees, completing the annual life cycle.
Effective control of green apple aphids requires an integrated approach combining cultural practices, monitoring, and timely interventions during the vulnerable spring periods.
Ants form mutualistic relationships with aphids, actively protecting them from natural enemies in exchange for honeydews.
Inspect orchards regularly from bud break onwards for:
Early monitoring allows biological control measures to be introduced before populations reach damaging levels.
Koppert supports the biological control of green apple aphid with a range of natural enemies, including parasitic wasps, lacewings, hoverflies, ladybirds, and predatory midges. When introduced early and combined with regular monitoring, these beneficial insects help suppress aphid populations naturally and support sustainable apple production.