The California Department of Food and Agriculture issued a quarantine following the detection of the citrus disease Huanglongbing (HLB), or citrus greening, in a single citrus tree in an unincorporated area of San Bernardino County, near Montclair. This is the first time the plant disease has been detected in San Bernardino County. CDFA is working with the USDA and the San Bernardino County and Los Angeles County agricultural commissioners on this project. The 93-square mile quarantine area will link up with existing quarantines in Los Angeles and Orange Counties, creating a contiguous 1,015-square-mile area. The new portion is bordered on the north by I-210; on the south by Chino Airport; on the west by Highway 57; and on the east by Ontario International Airport.  HLB quarantine maps for San Bernardino and Los Angeles counties are available online here. Quarantines are already in place for HLB in portions of Los Angeles, Orange and Riverside counties.

The quarantine prohibits the movement of all citrus nursery stock or plant parts out of the quarantine area. Provisions exist to allow the movement of commercially cleaned and packed citrus fruit. Fruit that is not commercially cleaned and packed, including residential citrus, such as oranges, lemons, grapefruits, and kumquats, must not be moved from the property on which it is grown, although it may be processed and/or consumed on the premises, according to CDFA.