The good news about this disease is that controls are available and now is the time to spray. Two to three applications of a fungicide applied when growth begins through May can help save infected trees. Unfortunately there is a problem with Scotch pine that cannot be controlled by the use of chemical sprays. This problem is called pine wilt. Pine wilt is the result of an attack by a pathogen known as a nematode.
Nematodes reproduce in the vascular system of the plant, reducing the flow of water and nutrients.
Once infested, the tree will rapidly die, usually in the late summer through early winter. Removal of the tree is recommended to help reduce the spread. Determining the cause of the evergreen problems is the first step in helping to revive the landscape tree or shrub. Extension can provide this service. Trained volunteers can assist in solving your growing concern.