Elm buprestid beetle

Systematic position: The elm buprestid beetle (Agrilus convexicollis) belongs to the order Coleoptera and the family Buprestidae. These metallic wood-boring beetles are significant pests that cause severe damage to trees by boring into the cambium and xylem layers beneath the bark.

Host plants: The primary hosts for this species are members of the genus Ulmus (elm trees). While the insect often targets stressed, weakened, or injured trees, it can also infest healthy elm trees during outbreaks, leading to rapid decline and mortality of the host plant in urban and forest settings.

Biology and life cycle: The life cycle involves a complete metamorphosis. Adult beetles typically emerge in late spring or early summer to feed on foliage for maturation. Females lay eggs in bark crevices. Upon hatching, larvae immediately bore into the tree, constructing winding galleries under the bark, where they feed and develop before pupating within the wood.

Damage and economic impact: The damage is primarily caused by larval feeding, which disrupts the vascular system, preventing the flow of nutrients and water. Typical symptoms include canopy dieback, leaf chlorosis, and the presence of D-shaped exit holes on the bark surface. Left unchecked, infestation leads to branch dieback and eventually the death of the entire tree.

Protection measures: Integrated pest management (IPM) is essential for controlling Agrilus convexicollis. Sanitation is the most critical step: promptly removing and destroying infested wood before adults emerge is crucial to breaking the life cycle. Preventive insecticide treatments applied to the trunk during the peak flight period can protect high-value specimen trees in urban environments.