Four HLB Trees in San Gabriel, Quarantine Declared

Taylor HillmanCitrus

Huanglongbing on Mandarin Oranges

Huanglongbing on Mandarin Oranges

Huanglongbing (HLB) has been confirmed four times in San Gabriel, in a kumquat tree on a residential property, in a lime tree on an adjacent residential property, and in calamondin and mandarin trees on residential properties in close proximity to the original find. An 87-square mile quarantine in the San Gabriel area of Los Angeles County has been added to the existing HLB quarantine in the Hacienda Heights area following the detection of the citrus disease also known as citrus greening. The California Department of Food and Agriculture has an update.

Update on San Gabriel HLB

The quarantine boundaries are on the north, E. Orange Grove Blvd.; on the east, N. Lemon Ave.; on the west, Griffin Ave.; and on the south W. La Habra Blvd.

This area is part of a much larger quarantine already in place for the Asian citrus psyllid (ACP), the pest that spreads bacteria-causing huanglongbing. The new quarantine will prohibit the movement of all nursery stock out of the area, while maintaining existing provisions allowing the movement of only commercially cleaned and packed citrus fruit. Any fruit that is not commercially cleaned and packed, including residential citrus, must not be removed from the property on which it is grown, although it may be processed and/or consumed on the premises.

“The success of any quarantine depends on cooperation from those affected,” said CDFA Secretary Karen Ross. “The stakes couldn’t be higher for California citrus. We urge residents in the San Gabriel area to do all they can to comply.”

California Department of Food and Agriculture, the USDA and the Los Angeles County agricultural commissioners continue their work to investigate the source of the disease, to survey and test for it throughout the Los Angeles Basin, and to continue with ground treatment of citrus trees within 800 meters of the find sites – which began earlier this week. In the long term, the strategy is to control the spread of ACP while researchers work to find a cure for the disease.

The disease is bacterial and attacks the vascular system of plants. It does not pose a threat to humans or animals. The ACP can spread the bacteria as the pest feeds on citrus trees and other related plants. Once a tree is infected, there is no cure; it typically declines and dies within a few years.

Huanglongbing is known to be present in Mexico and in parts of the southern United States. Florida first detected the disease in 2005, and the University of Florida estimates that the disease causes an average loss of 7,513 jobs per year, and has cost growers $2.994 billion in lost revenue since then. Huanglongbing has also been detected in Georgia, Louisiana, South Carolina and Texas as well as Puerto Rico and the U.S. Virgin Islands.

A total of 15 states or territories are under full or partial quarantine due to the presence of the ACP: Alabama, American Samoa, Arizona, California, Florida, Georgia, Guam, Hawaii, Louisiana, Mississippi, Northern Mariana Islands, Puerto Rico, South Carolina, Texas, and the U.S. Virgin Islands.

ACP was first detected in California in 2008 and quarantines for the pest are now in place in 17 California counties. If Californians believe they have seen evidence of huanglongbing in local citrus trees, they are asked to please call CDFA’s toll-free pest hotline at 1-800-491-1899. For more information on the ACP and huanglongbing, please visit: