The most common hosts in Oklahoma are Scotch, Austrian, and Japanese Black Pines, although other pines can become diseased too. The disease has only been reported in the eastern half of Oklahoma.
The disease is spread by the pine sawyer beetle, genus Monachamus, which lays eggs in the dying or dead tree. When the adult beetles emerge from the pine in the spring, they carry the nematode that causes pine wilt to healthy pines. As the beetle feeds, nematodes are deposited in the plant, which causes pine wilt to develop in the pine tree.
Pine wilt is a lethal disease of pines that can suddenly appear in pines that are usually at least 15 years old, although occasionally in trees as young as 7 years. Pine wilt is most common in the fall when the needles of the entire tree begin to turn light green or brown. Within a few weeks, the trees are usually dead and brittle.
The disease is too unpredictable and random to spray for control. The disease develops very quickly and there is no control. Prevent further disease by removing the diseased tree. If able to do so, burn the wood to reduce the chance of disease spread to nearby trees.