Alder Leaf Beetle

Natural Habitat

Damp environments, such as riverbanks, wetlands, and woodlands where alder and hazel trees are present.

Diet & Feeding

Herbivorous; both adults and larvae feed on the leaves of alder, hazel, birch, and beech trees.

Behavior Patterns

Adults hibernate in leaf litter or under bark and emerge in spring. They skeletonize leaves while feeding and can produce several generations per year in warmer climates.

Risks & Benefits

Generally considered a pest for alder and hazel trees as they can cause significant defoliation, though they rarely kill established trees. They have no direct risk to humans.

Identified on: 5/1/2026