The California Department of Food and Agriculture (CDFA) and the United States Department of Agriculture (USDA) have confirmed the detections of the citrus disease known as huanglongbing (HLB) or citrus greening in Orange County. The disease was detected in plant material taken from a lemon tree in a residential neighborhood in La Habra and from three trees (2 lemons, 1 grapefruit) in a residential neighborhood in Anaheim. HLB is a deadly disease of citrus plants and closely related species and can be transmitted from tree to tree by the Asian citrus psyllid.
CDFA, in cooperation with the USDA and the Orange County Agricultural Commissioner, has begun an extensive survey and limited treatment program in response to the detections. CDFA crews have removed and disposed of the infected trees and are preparing to conduct treatment of citrus trees for Asian citrus psyllid infestations within 800 meters of the find sites. By taking these steps, a critical reservoir of the disease and its vectors will be removed, which is essential to protect the surrounding citrus from this deadly disease.
HLB is a bacterial disease that attacks the vascular system of plants. It 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 declines and dies within a few years.
CDFA has expanded an existing HLB quarantine to include a portion of La Habra and will soon expand it further to Anaheim. The quarantine prevents the sale of all host nursery stock and the movement of all host plants and fruits within a five-mile radius of the find sites and applies to residents and commercial operations alike. The HLB quarantine maps for Los Angeles and Orange Counties are available online. Please check this link for future quarantine expansions in these counties, should they occur. Quarantines in new counties will be announced separately.
CDFA, in partnership with the USDA, local county agricultural commissioners and the citrus industry, continues to pursue a strategy of controlling the spread of the Asian citrus psyllids while researchers work to find a cure for the disease.
HLB is known to be present in Mexico and in parts of the southern United States. Florida first detected the pest in 1998 and the disease in 2005, and the two have now been detected in all 30 citrus-producing counties in that
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 there.
The Asian citrus psyllid was first detected in California in 2008, and quarantines for the pest are now in place in 29 California counties. If Californians have questions about the ACP or HLB, they may call CDFA’s toll-free pest hotline at 1-800-491-1899 or visit: www.cdfa.ca.gov/plant/acp/