Hawthorn root aphid

Systematic position: The hawthorn root aphid (Eriosoma crataegi) belongs to the order Hemiptera and the family Aphididae. It is a specialized pest characterized by a complex life cycle involving migration between different host plants and a hidden, soil-dwelling phase on root systems.

Host plants: The primary host for this species is the hawthorn, where overwintering occurs. The secondary hosts are typically apple trees. The aphid colonizes the roots of these trees, where it can cause significant hidden damage if left uncontrolled for long periods.

Biology and life cycle: The pest exhibits a migratory life cycle. Eggs overwinter on hawthorn branches. In spring, winged forms migrate to apple trees, where the next generations colonize the root system. Throughout the summer, multiple generations of wingless aphids develop on roots, while in the autumn, a return migration to hawthorn occurs for mating and egg deposition.

Damage and economic impact: By feeding on roots, the aphids inject secretions that cause gall formation and tissue deformation. This prevents proper nutrient and water uptake. Infected trees show stunted growth, yellowing foliage, and reduced yields. In severe cases, especially in young orchards, the infestation can lead to tree decline and death.

Management strategies: Controlling soil-dwelling pests requires specific attention:

• Strict inspection of nursery stock to prevent the introduction of aphids.
• Removal of hawthorn hedges and wild shrubs near apple orchards to break the life cycle.
• Application of systemic insecticides specifically for soil drenching during peak periods.
• Maintenance of soil health to promote rapid root regeneration.
• Biological control through the encouragement of ground-dwelling predators.