In June 2021, the Animal and Plant Health Inspection Service (APHIS) expanded the Phytophthora ramorum quarantine area in Del Norte County, California. APHIS took this action in response to the confirmation of P. ramorum in the county on September 19, 2020. The California Department of Food and Agriculture has established an intrastate quarantine for the areas in Del Norte County that mirrors the federal regulatory requirements as specified in 7 CFR 301.92.
P. ramorum is the pathogen that causes sudden oak death (SOD), ramorum leaf blight or ramorum dieback. SOD was first reported in 1995 on tan oak in Mill Valley, Marin County, Calif.
Through ongoing surveys, APHIS continues to define the extent of the pathogen’s distribution in the U.S. and uses quarantine areas and public outreach to limit its artificial spread beyond infected areas. Details on APHIS-designated P. ramorum quarantine and regulated areas and the conditions to move regulated articles are in 7 CFR 301.92 and at: aphis.usda.gov/plant-health/sod.