Ash bark beetle

Systematic position: The ash bark beetle (Hylesinus crenatus) is a member of the order Coleoptera, belonging to the family Curculionidae and the subfamily Scolytinae. It is widely recognized as a significant stem pest that specifically targets ash species within various forest ecosystems and urban plantations.

Host plants: The primary host for this beetle is the common ash (Fraxinus excelsior). While it occasionally infests related species within the Oleaceae family, its main economic and ecological impact is observed in European ash populations that are weakened by environmental stress, such as drought or fungal diseases.

Biology and lifecycle: The lifecycle of Hylesinus crenatus is strictly tied to the bark and phloem of its host. Adult beetles overwinter in tunnels within the bark or in the soil near the base of the trunk. In the spring, they emerge to mate, and females construct galleries beneath the bark to lay eggs. Larvae hatch and begin feeding on the cambium, constructing individual tunnels that disrupt the vascular system of the tree.

Damage character and impact: The damage caused by these beetles is severe due to the mechanical destruction of the conductive tissues. As larvae and adults feed, they create complex networks of galleries, which effectively girdle the tree. This process restricts the flow of water and nutrients, leading to crown dieback, foliage yellowing, and eventually the death of the entire tree.

Protection measures: Management of the ash bark beetle relies heavily on silvicultural practices and integrated pest management strategies. Because chemical control is difficult once the beetle is beneath the bark, prevention through maintenance of stand health is critical.

• Removing and destroying infested timber before adult emergence.
• Maintaining high tree vigor through proper irrigation and soil care.
• Monitoring flight patterns using attractant-based traps.
• Executing selective sanitary thinning of the forest stand.