Willow weevil

Systematic position: The willow weevil (Otiorhynchus salicicola) belongs to the order Coleoptera and the family Curculionidae. It is a significant pest known for targeting woody ornamental plants and various species within the Salicaceae family, often causing aesthetic and physiological damage in nurseries and urban landscapes.

Host plants: The primary hosts for this species include willow (Salix) varieties, though it can also infest other deciduous trees and shrubs. The insect affects plants at different stages of growth, causing damage to foliage in its adult stage and to the root system during the larval stage of its development.

Biology and life cycle: The lifecycle of Otiorhynchus salicicola consists of egg, larva, pupa, and adult stages. Adult weevils are nocturnal, remaining hidden in the soil or under debris during the daylight hours. The larvae thrive in the soil, feeding on roots, which allows them to remain undetected until significant damage to the plant's health has already occurred.

Character of damage and harmfulness: Adults cause defoliation by eating the margins of leaves, resulting in typical scalloped edges. While this reduces the plant's photosynthetic capacity, the root-feeding activity of the larvae is often more destructive, leading to stunted growth, wilting, and potential death of young plants due to root damage.

Protection measures: Integrated Pest Management (IPM) is crucial for controlling this species. Cultural practices such as maintaining clean cultivation and soil aeration can help disrupt the larval environment. Chemical control involves the application of appropriate insecticides to the canopy to target adults and the use of soil drenches to suppress larval populations.

• Nocturnal monitoring of adult activity using light traps.
• Proper soil management to disrupt the larval lifecycle.
• Use of insecticides labeled for systemic or contact control.
• Removal of leaf litter to reduce daytime hiding spots for adults.