Sudden oak death expands in San Francisco Bay Area

Aerial and ground surveys have documented 375,700 new cases of dead live oak and tan oak trees over 54,400 acres of California where the pathogen that causes sudden oak death is known to exist, reported the San Francisco Chronicle. Last year there were 38,000 dead trees covering 8,000 acres.

Diseased trees were even found in Golden Gate Park, where there is no obvious source of the pathogen, such as nurseries or wildland.

"It's puzzling that we found it there because it's a totally urban environment, and I really didn't expect it. It shows how complicated and adaptable this organism is," said Matteo Garbelotto, UC Cooperative Extension specialist in the Department of Environmental Science, Policy and Management at UC Berkeley. "The area doesn't have a lot of oaks, so I'm not worried about oaks there, but I'm worried about other plants being infected and, of course, people carrying it on their shoes."

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