Huanglongbing Detection in Mexicali Puts Pressure on California Citrus Growers and Residents to Protect Their Trees


pest-01-ACP-adults-005-RogersMexico and the United States are Working Collaboratively to Prevent Spread of the Disease in the Cali-Baja Mega Region

MEXICALI, MEXICO – The deadly and incurable citrus tree disease Huanglongbing, also known as HLB or citrus greening disease, was detected 23 miles south of the U.S.-Mexico border in a small citrus grove in Mexicali.

HLB kills citrus trees and has no cure. The disease is spread by a pest called the Asian citrus psyllid as it feeds on citrus tree leaves and stems. The HLB detection in Mexicali was in a single citrus tree, and a single Asian citrus psyllid tested positive for carrying the bacteria that causes the disease as well. Agriculture officials in Mexico are working quickly to survey the surrounding citrus trees, as a part of their ongoing efforts to protect Mexico citrus from this devastating plant disease through monitoring, removal of diseased trees and Asian citrus psyllid treatments.

In California, local and state agriculture officials are also monitoring citrus trees in the border region, placing insect traps, releasing a natural predator of the Asian citrus psyllid and conducting treatments to protect citrus trees from the pest.

“With Huanglongbing now detected in Mexicali, Ensenada and Los Angeles, Southern California citrus growers – including commercial farmers and residents who have orange, lemon or other citrus trees growing at their homes – must be on guard,” said Victoria Hornbaker, citrus program manager for the California Department of Food and Agriculture.

“Huanglongbing knows no borders. Residents throughout this region must work together,” she said.

The Citrus Pest & Disease Prevention Program recommends the following actions to protect the community’s citrus trees:

  • Do not move citrus fruit, plants or cuttings. Obey federal and state quarantine laws that limit the movement of citrus material into and out of the region. These measures are in place to prevent diseased plants and the Asian citrus psyllid from being transported to new areas.
  • Cooperate with agriculture officials. Trained agriculture specialists are scouting citrus trees in Southern California, collecting plant samples and treating citrus trees to protect against the Asian citrus psyllid. By working together with these agriculture crews, residents will help protect their community’s citrus.
  • Protect citrus trees against the pest. Ask your local nursery or home and garden center what products can help protect your citrus tree from the Asian citrus psyllid. The best way to protect against the disease is to stop the pest.

The first detection of HLB in California was in Hacienda Heights in 2012. In 2015, multiple incidences of the disease were found in San Gabriel, a nearby community. A total of 27 diseased citrus trees have been detected and removed, all within Los Angeles County. In Mexico, HLB was detected in Ensenada earlier this year. The disease is also present in southern areas of the country. Agriculture officials from both countries are working collaboratively to prevent the disease from spreading.

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