Managing Bark Beetles in Urban and Rural Trees

Bark beetles belong to a group of small, but destructive in-sects that kill or damage trees by tunneling under the bark to reproduce. Much of the damage is caused by the developing offspring. Trees stressed by unfavorable environmental condi-tions, disease, defoliation, age, or poor tree care are most sus-ceptible. Bark beetles commonly attack conifers, however some prefer hardwoods, e.g., oak, elm or Prunus species. Most are fairly specific as to their preferred host tree(s), and each species favors a particular part of the tree. For instance, it is not unusual to find one species of beetle attacking the top and large branches, (Tree Note #8) another attacking the main trunk, (Tree Note # 13), and yet another attacking the tree base (Tree Note #9). Natural resistance to bark beetle attack in pines and other co-nifers involves sustained pitch flow from their entry wounds