Huanglongbing Detections in Urban Southern California

The following press release was distributed on April 13, 2017 by the Citrus Pest & Disease Prevention Program.

Huanglongbing was confirmed in a single citrus tree in the City of La Habra in Orange County on April 11. This new find will result in a new HLB quarantine area, which will link the existing quarantines into a contiguous zone spanning portions of Los Angeles and Orange counties.

Additionally, two samples of Asian citrus psyllids in Anaheim tested positive for carrying the bacteria that causes HLB. These lab results were confirmed last week, and the California Department of Food and Agriculture is treating host plants in the surrounding 800-meter area. No diseased tree has been detected thus far, but the California Department of Food and Agriculture staff have been diligently implementing an intensive survey in the area. This approach includes sectioning trees into four to eight sections and evaluating the leaves from each section independently.

This thorough approach has proven successful in identifying diseased trees. On April 8, intensive survey resulted in the detection of another diseased tree in the HLB core area of San Gabriel; another two positive trees in San Gabriel were confirmed April 11. The total number of diseased citrus trees detected in California is now at 53.

The detection of HLB in a La Habra citrus tree is alarming, as are the samples of Asian citrus psyllids from Anaheim that were found to be carrying the bacteria that causes HLB. While this activity is disheartening, California should be proud that the disease has been, thus far, contained to urban pockets of Southern California. Not a single commercial citrus tree has been lost to the disease. Sadly, our industry partners in Florida are left with a fraction of production after battling HLB for more than a decade. We must continue holding the line in California until research finds a cure for HLB.

Read about ACP and HLB distribution at http://ucanr.edu/sites/ACP/. For more detailed information on ACP and HLB, reference UC IPM's Asian Citrus Psyllid and Huanglongbing Pest Note.