On July 10, the California Department of Food and Agriculture (CDFA) and the U.S. Department of Agriculture (USDA) confirmed the second case of the citrus disease Huanglongbing (HLB), or citrus greening, in the Golden State.

Officials say HLB was detected in plant material from a kumquat tree in a residential neighborhood in the San Gabriel area of Los Angeles County. 

This is the second detection of HLB in California. The first detection in 2012 was found in a residential citrus tree in Hacienda Heights, about 15 miles from the new San Gabriel find. 

“CDFA is moving quickly to protect the state’s citrus,” said CDFA Secretary Karen Ross.

Infected tree removed

According to a CDFA statement, a CDFA crew removed and disposed of the infected tree and will conduct treatment of citrus trees for any Asian citrus psyllid (ACP) infestation within 800 meters of the find site.

The ACP pest is the primary vector of HLB.

“By taking these steps, a critical reservoir of disease and its vectors will be removed which is essential,” Secretary Ross said. 

CDFA reports an intensive survey of local citrus trees and psyllids is underway to determine if HLB exists anywhere else in the San Gabriel area.

Rapid quarantine expected

Planning has begun for an area quarantine to limit the spread of the disease by restricting the movement of citrus trees, citrus plant parts, green waste, and all citrus fruit except commercially cleaned- and packed-citrus.

As part of the quarantine, citrus and closely related plants at nurseries in the area will be placed on hold.

Currently, ACP quarantines are in place in 17 California counties.

Residents of quarantine areas are urged not to remove or share citrus fruit, trees, clippings-grafts or related plant material. Citrus fruit may be harvested and consumed onsite. 

Secretary Ross added, “We have been planning and preparing for HLB detections with our growers and our colleagues at the federal and local levels since before the Asian citrus psyllid was first detected here in 2008.”

HLB kills citrus trees

HLB is a bacterial disease that attacks the vascular system of plants. The disease does not pose a threat to humans or animals.

The Asian citrus psyllid can spread the bacteria as the pest feeds on citrus trees and other plants. Once a tree is infected, there is no cure. It typically dies within several years.

“Citrus is a cherished part of our landscape and our shared history, as well as a major agricultural crop,” the Ag Secretary said.

CDFA, in partnership with the USDA, local agricultural commissioners and the citrus industry, continues to pursue a strategy of controlling the spread of Asian citrus psyllids while researchers work to find a cure for the disease.

HLB is present in Mexico and in parts of the southern U.S.

In 1998, Florida became the first U.S. state to detect the pest, followed by the first disease find in 2005. The ACP-HLB combo has been detected in all 30 citrus-producing counties in the Sunshine State.

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 HLB was first detected in that state.

HLB has also been detected in Georgia, Louisiana, South Carolina and Texas, plus in Puerto Rico and the U.S. Virgin Islands.

Fifteen 15 states or territories are under full or partial quarantine due to the detected presence of the Asian citrus psyllid: 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. 

To report a pest, call the CDFA’s toll-free pest hotline at (800) 491-1899.

More information on the ACP pest and HLB disease is available online.

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