Effective November 16, 2021, the Animal and Plant Health Inspection Service (APHIS) and the California Department of Food and Agriculture (CDFA) established a Mediterranean fruit fly (Medfly) quarantine area in San Bernardino and Los Angeles Counties, California. APHIS is applying safeguarding measures and restrictions on the interstate movement or entry into foreign trade of regulated articles from this area. This action is in response to the CDFA’s confirmation of a mature, unmated female Medfly on October 25, and a subsequently confirmed male Medfly on November 9 from Jackson traps placed in backyard citrus trees in residential areas of Upland, California. There are 15.75 acres of commercial agricultural production in the quarantine area. Currently, the quarantine area encompasses 95 square miles.