While there is no cure for Sudden Oak Death or other P. ramorum-associated diseases, there are preventive measures that may protect plants, and a treatment that has been shown to prevent or slow the progression of the disease in some hosts. More information and links to other resources can be found below. The most current research on P. ramorum can be found at: UC Berkeley Forest Pathology and Mycology website

Treatments for individual trees
Wildland treatments
 

Individual trees

The California Department of Pesticide Regulation approved a special registration for Agri-Fos fungicide in October 2003. It is currently the only treatment approved by the State for use against Phytophthora ramorum infections on oaks and tanoaks. The compound is best used as a preventative measure and is NOT A CURE, but it can help protect trees from getting infected, as well as suppress disease progression in very early infections.

The phosphonate compound may be injected or mixed with a surfactant and sprayed on the trunk for absorption through the bark. It requires 3-6 weeks to be assimilated by the plant and start being effective against the pathogen, and must be reapplied annually. The optimal treatment routine calls for the first treatment in November-December (if temperatures are still mild), with a booster treatment 6 months later, and then repeated every 18 months.

Since the treatment must be made to healthy trees, and the pathogen's distribution and activity is patchy and somewhat unpredictable, it is difficult to determine which trees need to be treated. Generally, you should treat healthy, high-value oak or tanoak trees within 50 m of other infested plants. You may want to treat healthy, high-value oaks or tanoaks if they are surrounded by healthy California bay laurel and there are known infections between 50 m and 300 m away. Treatment is NOT recommended in areas where infested plants are not already present. Although these treatments are best used as a preventative approach, it may be possible to prolong the life of trees already infected by Phytophthora ramorum. Research results indicate that treatments are effective only if trees are treated within the first two months of infection. Treatment of trees having displayed symptoms for six months or longer is not recommended.

More details and information can be found here:
Chemical Treatment for Sudden Oak Death
 

Wildland Treatments

In wildland situations, burning may also be an effective management technique as this kills the pathogen and consumes infectious plant material. More research is needed before specific burning recommendations can be made, however.

Summary of Fire and P. ramorum issues (PDF) (Posted 11/7/06)

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