The mighty oak, California’s signature tree, is being helped by the severe drought the state is experiencing, which is slowing down the spread of sudden oak disease. The number of contagious spores that have killed hundreds of thousands of oak trees has been drastically reduced by the dry conditions.
Surveys taken between April 4 and June 5 of this year show an infection rate of between 2 and 10 percent of bay laurel trees, compared with 20 to 80 percent during a normal year when rainfall is abundant. Pinpointing infected bay laurels is the key to fighting the pathogen, because bays are a waylay point for the microbes before they do their dirty work on oaks.
California bay laurels are the vectors for this disease, storing up the spores on their leaves and spreading them in the winds to nearby oak trees. The drought is allowing scientists time to battle the microscopic pathogen.