Willow leaf aphid

Systematic position. The willow leaf aphid (Chaitophorus vitellinae) belongs to the order Hemiptera, family Aphididae. This insect is a specialized feeder that maintains a close biological association with trees of the genus Salix (willows).

Affected crops. The pest primarily targets various species of willow, including white willow (Salix alba) and brittle willow (Salix fragilis). It is commonly found in nurseries, forest plantations, and urban landscapes where willow trees are used for ornamental or restoration purposes.

Biology and life cycle. The species is monoecious, meaning it completes its entire life cycle on the same host plant. It overwinters as eggs deposited on the bark of twigs. In the spring, nymphs emerge and develop into apterous (wingless) fundatrices. Throughout the summer, multiple generations are produced, including winged individuals that facilitate the spread of the colony to nearby hosts.

Damage and harmfulness. The aphids form dense colonies on the undersides of leaves and on tender shoots. By sucking plant sap, they induce leaf curling, yellowing, and necrosis. Severe infestations can cause significant stunting of young shoots, leading to reduced vitality and weakened growth of the host tree during the critical vegetation period.

Protection measures. Management strategies include both chemical and cultural approaches. Regular monitoring of trees during the spring is crucial for early detection. If population levels exceed the economic threshold, the application of systemic or contact insecticides is recommended. Additionally, promoting biological control agents such as ladybirds and lacewings can help maintain aphid populations at manageable levels.