Overview
The Flatheaded Pine Borer is a wood-boring beetle that primarily attacks pine trees. Like other flatheaded borers, it targets weakened or stressed trees, making it a secondary pest that can accelerate tree decline.
The flatheaded pine borer (Chalcophora angulicollis), also known as the Western sculptured pine borer, is one of the largest and most distinct members of the Buprestidae family in Western North America. These beetles are easily identified by their impressive size—reaching up to 1.25 inches in length—and their metallic, “sculptured” appearance. Their dark, grayish-bronze bodies are marked with prominent longitudinal ridges and recessed iridescent spots, mimicking the texture of the pine bark they inhabit. While they primarily target Douglas-fir and various pine species, they are considered “secondary” pests because they almost exclusively attack dead, dying, or recently felled timber.
The life cycle of the flatheaded pine borer is relatively long, often taking two to three years to complete. The larvae, which possess the signature broad, flattened segment behind the head, bore deep into the wood, creating large, oval-shaped galleries packed with fine, powdery “frass” (borer dust). While they do not typically kill healthy standing trees, their extensive tunneling can significantly degrade the structural integrity and value of timber intended for lumber. For homeowners and forest managers, the presence of these beetles is usually an indicator of underlying tree stress or the presence of nearby “slash” (fallen branches and logs). Management focuses on the prompt removal of dead wood and maintaining the health of standing groves to ensure they remain unattractive to egg-laying females.
Identification
- Metallic beetle with elongated body
- Larvae with flattened head region
- D-shaped exit holes
- Visible bark damage and sap flow
Habitat
Found in pine forests, plantations, and landscaped areas with pine trees. Often associated with drought-stressed or damaged trees.
Behavior and Damage
Larvae feed beneath bark, creating galleries that disrupt nutrient flow. Severe infestations can weaken or kill trees.
Prevention and Control
Maintaining healthy trees and reducing stress factors are critical. Removing infested wood and monitoring tree health can help prevent outbreaks.