Forest Treatment Strategies for Phytophthora ramorum

Although there is no known cure or preventative on a landscape scale for sudden oak death (SOD), the plant disease caused by Phytophthora ramorum, a variety of management options. has been tested with the goal of developing an integrated program of treatment for the pathogen. This paper presents a first attempt to gather together individual management trials into an overall decision-making tool for landowners contemplating treatments for the disease. It conceptualizes these treatments as a matrix that matches available strategies-some of which are still substantially untested-to management goals for properties or landscapes of varying sizes. The major goals we envision for landowners who are making decisions about P. ramorum treatments include 1) minimizing property impacts from the pathogen when it is already established on a property; 2) strategically protecting particular geographic locations, areas of high-quality oak and tanoak resources, or "islands" of old-growth oak and tanoak; and 3) suppressing P. ramorum inoculum and limiting its spread on a landscape (or larger) level. For each goal, we consider a number of possible treatment approaches. A key principle for landowners to keep in mind when considering strategies for managing P. ramorum is that all treatments should complement long-term goals for the property. In general, the action that should be taken in an area should be appropriate to the size of an epidemic; the most effective treatment programs involve early intervention.