Detection of HLB Triggers Quarantine in Ramona Area of San Diego County

A new quarantine area was established on March 2 in the city of Ramona, San Diego County, following the detection of the deadly citrus tree disease Huanglongbing (HLB) in two citrus trees on a residential property. This is the first time the disease has been confirmed in the city of Ramona, marking the fifth area in San Diego County where HLB is known to be present. The find site property had a confirmed Candidatus Liberibacter asiaticus (CLas)-positive Asian citrus psyllid (ACP) detection in late January 2026. CLas is the bacteria carried by ACP that causes HLB. A quarantine area has been established with a five-mile radius from the detection site, and infected trees have been treated and removed.

The latest quarantine adds to the existing HLB quarantines in San Diego County in Oceanside, Rancho Bernardo, Valley Center and Fallbrook. The updated HLB quarantine maps are available here. Please check this link for future quarantine expansions, should they occur.

CDFA, in partnership with USDA, local County Agricultural Commissioners and the citrus industry, continues to pursue a strategy of controlling the spread of the ACP while researchers work to find a cure for HLB.