Willow flea beetle

The Willow flea beetle (Crepidodera violacea) is a specialized beetle species belonging to the family Chrysomelidae within the order Coleoptera. It is recognized by its distinct metallic violet-blue coloration, which is a key diagnostic feature for field identification when scouting for pests on willow trees.

The primary hosts for this insect are various species of the genus Salix (willow), including basket willows and ornamental varieties. The beetles typically target young foliage and terminal shoots, making them particularly problematic in nurseries and young plantations where rapid plant growth is essential for economic value.

The biology of Crepidodera violacea is characterized by overwintering as adults in protected microhabitats such as leaf litter and topsoil. As temperatures rise in early spring, adults emerge to feed on developing buds and leaves. Female beetles lay eggs on the leaves, and the emerging larvae continue the cycle of damage by feeding on the leaf epidermis and parenchyma.

Damage caused by this beetle manifests as a pattern of small, irregular holes or "shot-holes" across the leaf surface. In cases of severe infestation, the foliage may become heavily skeletonized, leading to premature leaf drop. This damage reduces the overall photosynthetic capacity of the tree, stunting its growth and diminishing its aesthetic or commercial appeal.

Effective management strategies require a multi-faceted approach. Monitoring should begin early in the season as soon as leaves appear. Sanitation, specifically removing and destroying leaf debris in late autumn, is critical to disrupt the overwintering life stage. Chemical control using approved systemic or contact insecticides is recommended only when scouting indicates that economic thresholds have been exceeded.