A newly-released UC Berkeley study followed cases of sudden oak death (SOD) in California and found levels of the pathogen that cause the disease in oak trees has tripled in the last year.
Matteo Garbelotto is a Forest Pathology Specialist at UC Berkeley. He is the founder of the study, which used volunteers to collect data. Garbelotto said the increases of the pathogen are caused by the recent wet and windy winters.
The biggest change, he said, is in the Carmel Valley in Monterey County, where SOD is spreading to more urban areas.
"[For twenty years, Big Sur] has consistently had the "worst amount of infections," Garbelotto said.
However San Luis Obispo County is once again in the clear of detectable cases. Garbelotto said the last year’s study tested several false positives of the disease, and this year’s study proved them unfounded.
He said it's difficult to detect the disease, because it infects the tree through its bark for many years before the tree actually dies.
"And we only perceive the very last stage. And the last stage could last as little as six weeks,” Garbelotto said. “That's why it's called sudden oak death, because visually, all of a sudden we see the entire tree drying out."
Garbelotto said next year’s study will again focus on San Luis Obispo County because with so many nearby areas infected, the county is high risk for SOD. The study will take place when the symptoms are most prevelant, in the springtime.
Head to sodblitz.org to find ways to participate in data collection.