Woolly apple aphid

The woolly apple aphid (Eriosoma lanigerum) is a significant pest of apple trees, belonging to the family Aphididae. The insect is easily recognized by the white, cotton-like waxy secretions that cover its body. When crushed, these aphids release a red fluid, which is why they are commonly referred to as "woolly" or "blood" aphids.

This pest infests various parts of the apple tree, including the trunk, branches, and root system. While they prefer apple trees, they can occasionally be found on other Pomoideae species. The presence of the pest is often indicated by the white, fuzzy patches on the bark, particularly in cracks, crevices, and around pruning wounds where the bark is soft.

The life cycle involves rapid reproduction, with multiple generations overlapping throughout the growing season. In favorable conditions, they reproduce parthenogenetically, leading to explosive population growth. They feed by piercing plant tissues with their mouthparts and sucking sap, which disrupts the tree's vascular system and nutrient transport.

Damage caused by Eriosoma lanigerum is characterized by the formation of characteristic galls or swellings on the branches and roots. These distortions weaken the tree, inhibit shoot growth, and lead to poor yields. In severe cases, particularly with young trees, the infestation can result in tree mortality due to root system damage and subsequent secondary infections.

• Planting resistant rootstocks to prevent root infestation.
• Applying biological control methods, such as the parasitic wasp Aphelinus mali.
• Ensuring proper orchard hygiene by removing dead bark and heavily infested branches.
• Implementing systemic insecticide treatments during the early season.
• Avoiding excessive use of nitrogen fertilizers to limit succulent shoot growth.