State agriculture officials declared a new citrus quarantine in Ramona on Monday after two residential trees tested positive for Huanglongbing (HLB), also known as citrus greening disease — one of the most destructive citrus diseases in the world.

The California Department of Food and Agriculture confirmed the detections were made during routine inspections, according to officials with the County of San Diego. There is no cure for HLB. Infected trees eventually die, and the fruit they produce is bitter and misshapen, making it unsuitable for sale or consumption.

Citrus is one of San Diego County's most economically significant crops, valued at nearly $140 million according to the 2024 Crop Report. The new Ramona quarantine is the first of its kind in that community and joins existing HLB quarantine zones in Oceanside, Rancho Bernardo, Valley Center, and Fallbrook.

More than 100 businesses are expected to be affected by the new restrictions, including growers with approximately 10 acres of commercial citrus, two commercial nurseries, and a farmer's market in downtown Ramona. The quarantine limits the movement of citrus plants, plant parts, and fruit outside the designated boundary. Agricultural operations that must transport fruit are required to follow strict treatment, cleaning, and packing requirements before doing so.

For East County residents with backyard citrus trees, county officials recommend the following steps: do not move citrus plants, leaves, or foliage into or out of the quarantine area; remove all leaves and stems and thoroughly wash backyard citrus before moving it off the property; and contact the County Agricultural Commission if you notice symptoms such as mottled yellow leaves in asymmetrical patterns. The disease spreads through the Asian Citrus Psyllid, an insect that can be treated with products commonly found at home and garden stores. Quarantine maps are available at the CDFA website.