Sudden Oak Death

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State SOD Quarantines (this link goes to a 120 KB PDF developed by the California Dept. of Food & Agriculture -- it applies to Oregon, California & Washington) 

Sudden oak death (SOD) is a serious plant disease that attacks many types of plants and trees common to the Pacific Northwest, including azaleas, big leaf maples, huckleberry, California bay laurel, camellia, myrtles, honeysuckle, Pacific madrone, Douglas fir, rhododendrons, and vibernum. It does not affect humans and is not a food safety concern.

Sudden oak death is caused by a pathogen called Phytophthora ramorum. The pathogen is not a fungus or a bacterium, but a member of a unique group of organisms called Oomycetes. Oomycetes share some characteristics of fungi but are biologically different. 

Symptoms of sudden oak death  

Symptoms vary from plant to plant, and may include leaf spots, needle and tip blight, shoot-tip dieback, and canker formations. Many other plant pathogens cause the same symptoms. The only way to confirm the presence of sudden oak death is through laboratory testing.

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Additional resources

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. [External link]

California Oak Mortality Task Force [External Link]

Oregon Department of Agriculture [External Link]

California Department of Food and Agriculture [External Link]

Sudden Oak Death and Phytophthora ramorum: A Guide for Forest Managers, Christmas Tree Growers, and Forest Tree Nursery Operators in Oregon and Washington[PDf 426 kb]

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