In five coastal counties of central and northern California, thousands of oak trees are dying. The cause of this increased mortality in coast live oaks, tan oaks, and black oaks is not yet fully understood, but the syndrome seems to be associated with a new species of the Phytophthora fungus. Termed “Sudden Oak Death” because of the rapid browning and death of the leafy canopy of the tree, this disease may infect an oak for months or even years before the tree succumbs. Representatives from a number of government, university, private, and non-profit organizations have formed the California Oak Mortality Task Force to address Sudden Oak Death through research, monitoring, management, education, and public policy. In November, the state allocated $100,000 to support the Task Force’s initial efforts. To quickly disseminate information to the public, the task force has created a comprehensive web site—www.suddenoakdeath.org—that covers the history of the disease, research into its causes and treatment, photos and descriptions of symptoms, distribution maps, and much more. If you are concerned about an oak tree that appears to be diseased, contact your local U.C. Cooperative Extension Farm and Home Information office, or your local County Agriculture Commissioner.
Bay Nature magazine ◦ January-March 2001