Asian Citrus Psyllids Found in Manteca, San Joaquin County

Sep 22, 2016

The following press release was distributed on Sept. 20, 2016 by San Joaquin County agricultural officials.

Insect that carries disease deadly to citrus trees found in San Joaquin County.

The San Joaquin County Agricultural Commissioner, in cooperation with the California Department of Food and Agriculture (CDFA) and the United States Department of Agriculture (USDA), has already begun an extensive survey in response to the detection of three Asian Citrus Psyllids (ACP) within the City of Manteca.

The three ACPs found in Manteca were detected on September 13, 2016 near N. Union Road and Lathrop Road.

These finds were adjacent to an existing delimitation area for ACP in Manteca that was initiated in 2014. The delimitation will now expand to a Northwest area of Manteca due to these finds.

As a result, the next steps that will be taken include the deployment of additional traps in the area and the performance of a visual survey to determine if there is an infestation. Treatment activities will be carried out on properties containing citrus within 400 meters of the find site.

A public meeting will be scheduled in advance of any treatment activity. This detection will result in an expansion of the current quarantine already existing in the southern section of San Joaquin County stretching from the eastern County border near Escalon west to the Alameda County line near the City of Tracy.

“The Asian Citrus Psyllid is a dangerous pest of citrus,” said Tim Pelican, San Joaquin County Agricultural Commissioner. “We are working to determine the full extent of this infestation so that we can protect our State's vital citrus industry as well as our backyard citrus trees. Working together we can prevent the spread of this invasive species and the harm it can cause.”

While San Joaquin County has very little commercial citrus there is a $10.7-billion-dollar industry statewide not counting the nursery industry, which has increased significantly in some of our neighboring counties in recent years. “It is our duty to not only help protect the industry in our nearby counties but also the citrus that many of us grow in our own backyards,” concluded Commissioner Pelican.

Background: The ACP is an invasive species of grave concern because it can carry the disease Huanglongbing (HLB), also known as citrus greening. ACP is found in tropical and subtropical Asia, Afghanistan, Saudi Arabia, Reunion, Mauritius, parts of South and Central America, Mexico, the Caribbean, and in the U.S. (Alabama, Arizona, Florida, Georgia, Hawaii, Louisiana, Mississippi, South Carolina, and Texas). ACP was first found in California on August 27, 2008 in San Diego County. In recent years, it has spread to Kern, Tulare, Fresno, Madera, Merced and Stanislaus counties in the San Joaquin Valley. All citrus and closely related species are susceptible hosts for both the insect and the disease. There is no cure once a tree becomes infected, the diseased tree will decline in health and produce bitter, misshaped fruit until it dies.

The citrus is safe to eat and the disease is not harmful to human health. HLB has been detected on eleven trees at nine different locations in the Los Angeles and Orange Counties. If you think you may have the pest please do not remove it or any plant materials from the area.

Residents in the area who think they may have seen the pest are urged to call the Pest Hotline at 1-800-491-1899. For more information on the Asian Citrus Psyllid and Huanglongbing disease, visit:

Learn more about the Asian citrus psyllid and huanglongbing disease by reading the detailed pest note on UC ANR's Statewide Integrated Pest Management website.

Watch this 4 minute video to see how to inspect your trees for ACP.