HLB spotted for the first time in Imperial County, California

The California Department of Food and Agriculture (CDFA), in collaboration with the US Department of Agriculture (USDA), confirmed the detection of Huanglongbing (HLB), also known as citrus greening disease, in Imperial County. 

This is the first time the malady has been spotted in a tree in this area of the Golden State. 

Map courtesy of CDFA.

The detection happened on a residential property in the city of Calexico and follows the first trapping of an Asian Citrus Psyllid (ACP), the main vector of greening disease, carrying the HLB-causing bacteria in November of 2025. 

State agents treated and removed the infected plant and are currently inspecting all citrus trees within a 250-meter radius of the detection site. The agencies will also treat the area to reduce the risk of an ACP infestation, a step considered crucial to contain the spread of the lethal disease. 

No citrus movements within the HLB-quarantined area

Per CDFA protocol, the confirmed presence of HLB triggers the establishment of a quarantine area with a 5-mile radius around the residential property where the infected tree was planted. The state agency keeps a live map on its website updated in real time if and when new psyllids are trapped. 

During the quarantine, no citrus nursery stock, host plants, or plant parts will be allowed to leave the restricted area. Citrus fruit harvested for commercial purposes will be able to travel only after being cleaned and packed, while non-commercial fruit must stay within the harvesting premises.

Map courtesy of CDFA.

There are currently six other HLB quarantined areas in California, comprising parts of Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura counties, where over 10,700 HLB-infected trees have been removed since 2012. 

*Maps courtesy of CDFA; main image courtesy of USDA.  

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