A backyard citrus tree can have a longer reach than its branches. In California, tissue samples from residential properties—not commercial orchards—have prompted another adjustment to the citrus greening map.
The additions cover 273.2 acres of commercial citrus near Santa Paula and along the Riverside–San Diego county line, according to the quarantine report. The distinction matters: a grove appearing inside a quarantine boundary is not, by itself, evidence that its trees tested positive.
A line through two citrus regions
The Riverside County portion reaches the Murrieta area and extends into San Diego County. The expansion took effect September 11, with the San Diego County additions identified as grids 484, 499 and 510 in a UC Agriculture and Natural Resources notice.
Near Santa Paula, the trigger was also a residential finding. Together, the locations show how citrus in yards and commercial blocks share a regulatory map even when the positive samples come from only one of those settings.
The disease does not stay a map problem
Huanglongbing, or citrus greening, is associated with the Asian citrus psyllid and has no cure. Infected trees decline over time, which is why California’s response includes both commercial groves and backyard trees, as CDFA explains.
That makes the residential origin of these detections more than a curious detail. The boundary records where officials are managing risk; it does not establish that every citrus tree inside it is infected.
For suspected Asian citrus psyllid or HLB detections, UC’s guidance directs residents and growers to their local County Agricultural Commissioner or UC Cooperative Extension office; suspected detections can also be reported to CDFA’s Pest Hotline at 1-800-491-1899, according to a UCANR webinar Q&A.