查看文章

One hundred eighty-seven sites were established in perennial watercourses and sampled for one to four years between 2004 and 2007 to monitor for the presence of Phytophthora ramorum throughout coastal central and northern California watersheds as well as portions of the Sierra Nevada mountain range. In 2007, 132 sites were monitored, including 65 new sites. The majority of the monitored watersheds have limited or no Pr at this time, but are near the epidemic range of P. ramorum and/or are considered high-risk for invasion by P. ramorum. Three currently infested watersheds in Sonoma, Humboldt, and Monterey Counties were included as a baseline for successful recovery of Pr. Rhododendron leaves were placed in mesh bags and secured in watercourses for one-to three-week intervals to bait for Phytophthora species. Recovered symptomatic leaves were plated on Phytophthora-selective medium …