Bronze birch borer : Observatree guides

The bronze birch borer (BBB, Agrilus anxius), a beetle belonging to the family Buprestidae, is a serious North American insect pest of birch trees (Betula species). The BBB causes extensive mortality to birch populations and can attack trees with stems greater than 2 cm in diameter and branches of 1 cm in diameter. Damage is caused by larvae feeding on the inner bark and cambium of the tree. Repeated attacks and the excavation of numerous winding galleries by the larvae cause disruption to water and nutrient transportation within the tree, leading to death of tissues above and below ground. In many cases tree mortality is observed within just a few years of the appearance of the first symptoms.