The California Department of Food and Agriculture (CDFA) has placed all of Los Angeles County under a quarantine regulating the movement of citrus and closely-related plants.

The quarantine follows the detection of several dozen Asian citrus psyllids in the Echo Park area. CDFA is working with the USDA and county officials and growers to implement the quarantine in an effort to prevent the spread of the Asian citrus psyllid in California.

The Asian citrus psyllid can carry the disease huanglongbing (HLB). Tests on the psyllids detected in Los Angeles County were negative for the disease. All citrus and closely related plant species are susceptible host plants for both the Asian citrus psyllid and HLB. There is no cure for HLB once a citrus tree becomes infected. The diseased tree will produce inedible fruit and decline in health until it dies.

“The quarantine is an important step toward stopping the spread of this pest,” said CDFA Secretary A.G. Kawamura. “This action protects our state’s citrus farmers and also protects our backyard citrus trees, which are equally susceptible to the HLB disease that these pests can spread.”

The states of Texas, Mississippi and Alabama have detected the Asian citrus psyllid but not the HLB disease. Florida, Georgia, South Carolina and Louisiana have detected both the pest and the disease. Since the disease was first detected in Florida in 2005, it has spread to all 32 citrus-producing counties throughout the state.

The quarantine area is comprised of approximately 4,000 square miles covering all of Los Angeles County. A map of the quarantine area is available at http://www.cdfa.ca.gov/phpps/pe/interiorexclusion/acp_quarantine.html.

All harvested citrus in the quarantine area must be commercially cleaned and packed before it can be moved out of the area. Nursery host plants may not be moved out of the quarantined area and the movement of cut greens, green waste and citrus fruit will be regulated and enforced by federal, state and county quarantine officials. Residents are urged to consume back yard citrus fruit at home and to refrain from transporting their backyard citrus, as well as citrus plants, out of the area.

A treatment program for the Echo Park area is still being developed. A public meeting to discuss details of the treatment has yet to be scheduled.

California’s citrus industry ranks first in the U.S. in terms of value and second (after Florida) in terms of production. California’s total citrus production has averaged 3.2 million tons per season over the past three seasons, about 24 percent of the nation’s total. California is the nation’s main source (80 percent) of fresh-market oranges, while Florida grows oranges mainly for juice. California also supplies 87 percent of the nation’s lemons (source: USDA Economic Research Service).