Asian citrus psyllid detected in Santa Clara County, prompting quarantine

A portion of northwestern Santa Clara County has been placed under quarantine for the Asian citrus psyllid, an insect that can spread a disease that’s deadly for citrus trees.

The move comes after the psyllids were detected in the city of San Jose, near Kelly Park.

The quarantine zone measures 99-square miles, bordered on the north by Alum Rock Park, on the south by Santa Teresa Boulevard, on the west by North Monroe Street, and on the east by Joseph D Grant County Park.

A map of the quarantine area is here.

The quarantine prohibits the movement of citrus and curry tree nursery stock out of the quarantine area and requires that all citrus fruit be cleaned of leaves and stems prior to moving out of the quarantine area.

Residents with backyard citrus trees in the quarantine area are asked not to transport citrus fruit or leaves, potted citrus trees, or curry leaves from the quarantine area.

Quarantines are also in place in Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara, Tulare, Ventura, and portions of Fresno, Kern, and San Luis Obispo counties.

The invasive insect species can carry the disease huanglongbing, also known as citrus greening. All citrus and closely related species, such as curry trees, 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.

For more information, visit the California Department of Food and Agriculture website.