To reduce the spread of SOD, a study conducted by the USDA recommends that Bay trees be separated from susceptible oaks per these specifications:

1. Removing bay from within 2.5 m (8.2 ft.) of the trunk of a susceptible oak
2. Extending bay foliage-oak trunk clearance to 5 m (16.4 ft.) where possible, especially in the direction(s) from which storm winds blow.
3. Pruning low branches to obtain up to 5 m (16.4 ft.) of clearance in the lower canopy even if upper canopy bay branches are present at closer horizontal distances
4. Eliminating poison oak climbing at canopy level within an oak or in adjacent tree within 2.5 m (8.2 ft.) of the oak trunk.

Depending on your circumstances, trimming back bays and other carrier plants/trees can be relatively easy. For the non-do-it-yourselfers we've heard recommendations for the following tree trimming contractors.