Last April, residents of Portola Valley and Woodside went out and collected samples to test for sudden oak death (SOD), and gave them to scientists from the University of California at Berkeley.

The results are in. Of 155 samples, 42 have been deemed positive for SOD, according to the Web site of the school's Forest Pathology and Mycology Lab.

Matteo Garbelotto, an adjunct assistant professor in environmental science, policy and management at UC Berkeley, will talk about the results at 7 p.m. Friday, Nov. 6, at Portola Valley's Historic Schoolhouse at 765 Portola Road.

The disease is incurable, but a supplier of a chemical treatment that strengthens a tree's natural defenses will be on hand to take group orders.

Click here to view the test results. The Web page includes a link to a spreadsheet that identifies specific samples. Click on the Woodside tab at the bottom of the spreadsheet.

An interactive map on the page can pinpoint a sample. On the map, a green tree indicates a non-positive sample, a yellow tree indicates a positive by molecular genetic analysis, and a red indicates a Petri-dish confirmation of a genetic analysis.

For more information, go to www.suddenoakdeath.org.

For local information, Woodside residents should contact Kevin Bryant at 851-6790 or kbryant@woodsidetown.org, and Portola Valley residents should contact Leslie Lambert at 851-1700, ext. 212, or llambert@portolavalley.net.

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