Pine Bark Beetles
Cooperative Extension Service, College of Agricultural and Environmental Sciences, The University of Georgia Bulletin 1097, October 1993, 8 pp.
Bark beetle attacks can be recognized by the presence of boring dust, pitch tubes on the outside of the bark, characteristic galleries under the bark, and beetle adults and larvae in the inner bark.
The presence of "pitch tubes" on the bark of trees is one of the best ways to identify bark beetle attack. However, pitch tubes may not form on stressed trees. Instead, attacks are indicated by the presence of brown boring dust. Use a good pair of binoculars to observe the middle and upper trunk and the base of large limbs for pitch tubes, since the initial attack of some bark beetles occurs at mid-trunk height or above. Observing the change in color of tree crowns is not a good method of locating beetle attacks since it may take several weeks or longer after the initial attack for the crowns to "fade" to a light yellowish-green or red.