Bronze flathead borer

Taxonomic position: The bronze flathead borer (Dicerca aenea) belongs to the order Coleoptera and the family Buprestidae. These metallic wood-boring beetles are significant pests that thrive in diverse environments, often targeting weakened or stressed trees in forests and cultivated landscapes.

Host plants: This pest primarily infests deciduous tree species. Common hosts include poplar, willow, alder, birch, and various fruit trees. The insects are particularly attracted to trees that are already compromised by drought, mechanical damage, or environmental stressors that make them vulnerable to infestation.

Biology and life cycle: The life cycle consists of four stages: egg, larva, pupa, and adult. Adult beetles emerge in late spring or summer, mating and laying eggs in bark crevices. The larvae bore into the inner bark and sapwood, creating extensive galleries that may last for one or more years before the insect completes its development into a pupa and then an adult.

Nature of damage and pest status: The damage is caused by the larval stage, which feeds on the cambium layer. This feeding disrupts the tree's vascular system, leading to wilting, branch dieback, and potentially the death of the entire tree. Heavily infested trees show visible decline, poor foliage, and localized bark necrosis which indicates the presence of galleries underneath.

Control measures: Management of the bronze flathead borer is focused on prevention and cultural practices. Maintaining tree vigor through proper irrigation and fertilization is key. Infested trees should be promptly removed and destroyed to prevent the spread of the population to healthy individuals. In nursery settings, insecticide sprays during the adult flight period can reduce egg-laying success.

• Sanitary pruning of infested branches.
• Removal of severely damaged trees.
• Maintaining tree health through proper care.
• Monitoring adult beetle activity.