Fungus Hits Redwoods, Firs

A fungal plague killing off California's beloved oaks continues to wrack up victims.

What started out a bad dream for California habitat has turned into an all-out nightmare. In 1995, the fungus Phytophthora ramorum was discovered to be killing off California's famed oak woodlands. Since then, what has come to be known as Sudden Oak Death has swept like wildfire from Monterey to the California-Oregon border laying waste to the state's oaks and tanoaks. Now the fungus has turned up on coast redwoods and Douglas-firs, widening its hit list to seventeen plant species.

Researchers from UC Berkeley and UC Davis isolated P. ramorum from redwood sprouts and saplings in every site they tested-groves in Jack London, Henry Cowell, and Armstrong Redwood state parks, Muir Woods, Big Sur, the UC Berkeley campus, and on Mount Tamalpais. While the infected fir trees were found at only a single site in Sonoma County, they appeared to be more strongly affected by the disease. However, scientists remain skeptical that the disease will kill mature trees.

The epidemic already has scientists concerned that it could drastically alter California landscape, but the recent discovery has politicians up in arms. Redwoods and Douglas-firs together make up more than half the economic value of the annual wood harvest. Additionally, coast redwoods draw tourists from around the world to see the stately trees, which can live for 2,000 years are found only in California and Oregon.

Governor Gray Davis has requested $10 million in federal aid from the Bush administration to battle the deadly fungus. Likewise, Senator Barbara Boxer has filed for $5 million in emergency funding.


Map: Colleen Sudukem


Douglas-fir (Pseudotsuga menziesii) displaying wilting of new shoots and some dieback of branches and needles. Photo: University of California Cooperative Extension in Marin

Redwood (Sequoia sempervirens) showing early symptoms of sudden oak death, detected on the needles (discoloration) and very small branches (cankers that produce bleeding sap on the bark’s surface). Photo: University of California Cooperative Extension in Marin

Web Links

Sudden Oak Death - Science Now

Sudden Oak Death - California Wild

UC Davis - Sudden Oak Death Site

California Oak Mortality Task Force

CalFlora - Susceptible Species