The value of salvaged timber may also be reduced by decay, stain or insect holes. Galleries excavated under the bark by southern pine beetles are commonly curved or S-shaped. This can distinguish their damage. Southern pine beetles overwinter in all life stages in the bark of trees. Development of all stages continues throughout the year, although it is much slower in winter.
Adults lay eggs in their excavated galleries.
Eggs hatch in two to nine days and the larvae enter the cambium layer, then the inner bark, enlarging their galleries as they grow. When mature, larvae bore to the outer dead bark, create a cell and pupate. Emerging adults bore out of the pupal cell directly through the outer bark, leaving a clear-cut, open hole. Adult emergence may continue for an extended period of time. Generally, emerging adults leave the host tree and aggregate on an adjacent tree or leave the area to find a suitable new host tree.