The California Department of Food and Agriculture has added 110 square miles to a quarantine zone for Asian citrus psyllid in Tulare County.

The zone may expand again later in June after the detection of a single psyllid west of Exeter near Farmersville, according to a news release. The size and scope of any added regulation is still being determined.

The latest expansion brings the total quarantine area in Tulare County to 856 square miles. An online map depicts the zone, which also includes Terra Bella, Lindsay, Dinuba, Orange Cove and Orosi.

Separate quarantines are in place in Fresno, Kern, Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara and Ventura counties.

The psyllid can carry the disease huanglongbing, or HLB, leaving trees vulnerable to citrus greening.