Destructive insects and diseases have been studied to identify major pests, to quantify their incidence and abundance, and to assess their impact on the Duke Forest. Red-heart, eastern gall rust, Annosus root rot and southern Fusiform rust are the most prevalent and destructive of the diseases found to affect coniferous species on Duke Forest. During recent periods of cyclical outbreak, the southern pine beetle has caused more loss than any other coniferous insect pest. Control measures are employed when they are judged to be economically and environmentally advisable.
These methods include, but are not limited to:
- removal of mature timber,
- maintenance of adequate spacing,
- proper matching of species and sites,
- shortening the rotation for certain species on high hazard sites,
- use of genetically improved planting stock, and
- use of fungicides and insecticides if necessary.
Hardwood defects that have been found to be most prevalent are heart rot, poor form, and trunk boring insects (which are especially common in the red oak group). Minimizing losses by using careful logging practices, cutting stumps flush with the ground to force low sprouting, practicing good fire management, and promptly removing poorly shaped trees are among the primary measures employed.
Because of the Forest’s commitment to research, demonstration and study plots illustrating insect and disease problems may be created by allowing certain pest conditions to remain unchecked. The deliberate allowance of such conditions is to be closely monitored in order to ensure the prompt implementation of control measures if necessary.