Asian Citrus Psyllid

Asian Citrus Psyllid insect on a plant

​In October 2014, CDFA detected an infestation of Asian citrus psyllid (ACP) in San Jose near Kelly Park. This is the first detection of ACP in Santa Clara County and the Bay Area. The ACP were detected in a residential neighborhood near Phelan Avenue and Roberts Avenue in San Jose.

In December 2014, a second infestation was discovered on Agua Vista Drive in northern San Jose. This detection is roughly 5 miles north of the Kelly Park detections.

In May, 2015, an ACP was detected just over a mile north of the Agua Vista Drive area. This detection widened the quarantine area, bumping the boundary into Alameda County. (see map below)

ACP is an invasive species of grave concern because it can carry the disease huanglongbing (HLB), also known as citrus greening. The insect is small - as small as a grain of rice. 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.

Efforts are focused on slowing the spread of this insect as much as possible. The disease has not yet been found in Northern California, but has been detected in Southern California and other parts of the country.

This insect and disease endangers not only our commercial citrus industry, but also our backyard gardens. If ACP spreads all across California, an introduction of HLB anywhere can spread like wildfire, and since there is no cure, we will no longer be able to have citrus in our backyard gardens.

Where is the disease, HLB?

HLB is present in Mexico and in parts of the southern U.S. Florida first detected ACP in 1998 and the disease in 2005, and the two have now been detected in all 30 citrus-producing counties in that state. There is no cure for the disease and the citrus industry has been hit hard from the fruit and tree loss. The University of Florida estimates the disease has tallied more than 6,600 lost jobs, $1.3 billion in lost revenue to growers and $3.6 billion in lost economic activity.

What is the State doing about this infestation?

Treatment activities will be carried out on all citrus plants surrounding the sites where the insects were trapped. Residents in the treatment area will be notified in advance of any activity.

What can you do to help?

ACP and HLB can be carried into California on citrus plants, cuttings, or fruit. Please do not accept any tree cuttings or plants from an uncertified source. The best way to carry ACP or HLB into California is by taking a cutting or plant from a friend that has an infected tree and doesn’t know it yet!

You can also help out by saying “yes” to a trap in your yard if the State Department of Food &Agriculture asks to hang one on your property. It’s due to the great cooperation of residents in the San Jose area that we were able to detect this invasive pest early and control it before it spread!

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, please visit the California Department of Food & Agriculture’s website in the link below.​



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