Huanglongbing Detected Again in San Gabriel

Apr 6, 2017

The following press release was distributed on March 28, 2017 by the Citrus Pest & Disease Prevention Program.

The California Department of Food and Agriculture crews conducting intensive, risk-based surveys detected eight citrus trees confirmed to be infected with Huanglongbing. All trees were in the core area of San Gabriel where HLB has previously been detected. This brings the total number of HLB-positive trees in California to 46.

CDFA routinely conducts HLB surveys throughout the state based on a risk model that considers factors that may make an area more likely to have a presence of the disease. CDFA has further fine-tuned this approach by increasing the number of samples pulled from citrus trees that are considered high risk. This strategic approach – developed by the CDFA lead diagnostician with input from the Citrus Pest & Disease Prevention Program and leading scientific researchers – has helped pinpoint infected trees.

State and local crews are building relationships with residents in the area, which not only helps gain access to properties, but also results in swift removal of trees identified as having HLB. While removal of diseased trees is mandatory, positive homeowner relationships encourage cooperation. Of the eight trees recently detected, seven have already been removed or been scheduled for removal by CDFA. Crews are contacting the property owner of the remaining citrus tree Tuesday, March 28, and will pursue quick removal.

In 2016, CDFA collected nearly 50,000 plant samples and nearly 80,000 Asian citrus psyllid samples to test for HLB. Since sample collection began in 2008, more than 400,000 plant and psyllid samples have been collected and processed. This diligent work has contributed to quick detection and eradication of diseased trees.

As a part of the Citrus Pest & Disease Prevention Program, CDFA will continue surveying and sampling the area for HLB and keep the industry abreast of finds as they occur.

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