Unstoppable Sudden Oak Death Kills a Million California Trees

"Healthy forests are especially important at a time of climate change — they’re an incredible tool to remove carbon dioxide from the atmosphere. Dead forests, on the other hand, can light the spark for wildfires, which are already showing a long-predicted uptick in activity.

In California’s coastal forests, health is anything but good. Since 1995, a pathogen that causes a phenomenon dubbed ‘sudden oak death’ (a far catchier name than that of the pathogen itself, Phytophthora ramorum) has taken out millions of oak and tanoak trees, particularly along the coast extending northward from Monterey County. That includes areas of Marin County, Sonoma County and Big Sur.

The pathogen is a water mold that affects different trees differently, and not all are susceptible. It will tear through a forest and kill some trees while leaving others standing."

Chris Mooney reports for the Washington Post May 2, 2016.