Which beetle is known for causing damage to structural timber?

The true powder post beetle is specifically recognized for its significant impact on structural timber. It is notorious for boring into hardwood, causing notable damage by creating tunnels as it feeds on the wood. This beetle's larvae can survive in the wood product for years before emerging as adults, leading to prolonged and often severe structural damage.

While other beetles mentioned, such as the deathwatch beetle, powder post beetle, and furniture beetle, may also cause wood damage, the true powder post beetle specifically targets structural timber and is associated with the fine powdery frass left behind as it burrows through the wood. This characteristic distinguishes it as a primary concern in terms of structural integrity and pest management in wooden structures.