citrus varieties

Unusual Citrus Varieties for Northern California

Daniel CooperCalifornia Corner, Varieties

A recent University of California Agriculture and Natural Resources (UC ANR) article described five “odd and unusual” citrus varieties that can be grown in northern California. They are Nagami kumquat, yuzu hybrid citrus, Flying Dragon orange, finger lime and Buddha’s Hand citron. The article noted that Nagami, yuzu and Flying Dragon are cold tolerant to well below freezing. Finger lime …

California

Quarantine Updates for California

Daniel CooperDiseases, Pests, Regulation

Federal and state agriculture officials have taken actions regarding Mediterranean fruit fly (Medfly) and sweet orange scab (SOS) quarantines in California. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) updated the quarantines. MEDFLY QUARANTINE REMOVED The agencies removed the Medfly quarantine in Alameda and Santa …

expansion

California Growers and Nurseries Affected by Quarantine Expansions

Daniel CooperCalifornia Corner, HLB Management, Regulation

The California Department of Food and Agriculture (CDFA) has expanded the huanglongbing (HLB) quarantine boundary in San Diego County following the confirmation of one HLB-positive residential citrus tree in Fallbrook. CDFA is also expanding the Asian Citrus Psyllid (ACP) Bulk Citrus Regional Quarantine Zone 6 to reflect the HLB quarantine boundary expansion. A map of the expanded boundary can be …

CEO

California Citrus Mutual Names New CEO

Daniel CooperCalifornia Corner

California Citrus Mutual (CCM) has selected Tom Danowski as its new CEO effective Sept. 1. Danowski most recently served 13 years as president and CEO of the Oregon Wine Board and Oregon Winegrowers Association. There, he helped drive the Oregon wine industry’s total annual economic impact from $2.7 billion to $8 billion, CCM reported.  Prior to working in Oregon’s wine industry, …

Medfly

California Medfly Infestation Eradicated

Daniel CooperCalifornia Corner, Pests

State, local and federal agriculture officials have eradicated a Mediterranean fruit fly (Medfly) infestation centered in and around the City of San Jose, California. The eradication ends a 241-square-mile quarantine that began on Aug. 19, 2025. The California Department of Food and Agriculture (CDFA), the U.S. Department of Agriculture (USDA), and the Santa Clara County and Alameda County agricultural commissioner’s …

standard

California Weighs In on OJ Standard Change

Daniel CooperCalifornia Corner, Orange Juice, Regulation

Like the Florida citrus industry, California Citrus Mutual (CCM) welcomed the recent U.S. Food and Drug Administration (FDA) update of the federal standard of identity for pasteurized orange juice (OJ). The action marks the first significant revision to the standard in more than 60 years and takes effect Aug. 19. The FDA reviewed consumer sensory data during its rulemaking process …

efforts

Efforts to Control Psyllids in California

Daniel CooperCalifornia Corner, Psyllids

Grove edges, detector dogs and the California Citrus Research and Field Trials (CA-CRaFT) Program were prominent topics in a virtual presentation about California’s efforts to control HLB-spreading Asian citrus psyllids (ACP). Ivan Milosavljevic, Citrus Research Board (CRB) integrated pest management entomologist, delivered the report. His June 23 presentation was part of the 2026 CRB Webinar Series. GROVE EDGES Conventional human …

biocontrol

Stepping Up Psyllid Biocontrol in California

Daniel CooperBiologicals, California Corner, HLB Management

California Citrus Research and Field Trials (CA-CRaFT) plans in Ventura County call for expanded activities and a stronger emphasis on biological control of the HLB-spreading Asian citrus psyllid (ACP) with the parasitic wasp Tamarixia radiata. In a June 23 virtual presentation, Citrus Research Board integrated pest management entomologist Ivan Milosavljevic reported that the Ventura County program will utilize self-release T. …

plant growth

Plant Growth Regulators in California Citrus

Daniel CooperCalifornia Corner, PGRs

University of California Riverside Extension subtropical horticulturist Mary Lu Arpaia recently discussed the uses of the plant growth regulators 2,4-D, NAA and ethylene in California citrus. Her June 9 presentation was part of the Citrus Research Board Webinar Series. 2,4-D One use of 2,4-D in California is to increase fruit size of navel oranges, grapefruit, mandarins and mandarin hybrids. For …

gibberellic acid

Gibberellic Acid Has Multiple Uses in California Citrus

Daniel CooperCalifornia Corner, PGRs

There are numerous preharvest and postharvest uses of gibberellic acid (GA) in California citrus, a University of California Riverside Extension subtropical horticulturist reported during a June 9 webinar. Mary Lu Arpaia’s GA discussion was a major portion of her broader topic of plant growth regulators in California citrus. Her presentation was part of the Citrus Research Board Webinar Series. WHAT …

glassy-winged sharpshooter

California Responds to Glassy-Winged Sharpshooter

Daniel CooperCalifornia Corner, Pests

The California Department of Food and Agriculture (CDFA) is responding after invasive glassy-winged sharpshooter (GWSS) insects were found on shipments of grapevines sold at select Costco locations in Northern California between April 21 and May 19. GWSS spreads the bacterium that causes Pierce’s disease, a fatal grapevine disease that threatens California vineyards. It can also damage citrus trees, landscape plants …

scale

California Red Scale Advisory Issued

Daniel CooperCalifornia Corner, Pests

Sandipa Gautam, University of California area citrus integrated pest management (IPM) advisor, issued an Extension advisory for California red scale (CRS). The scale is a key pest of citrus in the San Joaquin Valley. Key points of the advisory are as follows: CRAWLERS ARE ACTIVE The CRS life cycle starts as crawlers produced by overwintering females from the past season. …

citrus breeding

Funding Expanded for California Citrus Breeding

Daniel CooperBreeding, California Corner

The U.S. House Committee on Appropriations has included additional funds in the fiscal year 2027 Agriculture Appropriations bill for the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) citrus breeding program in Parlier, California. It is allocating an additional $500,000 in federal funding, on top of the $1.5 million previously granted, to expand the program into California. If approved, the program …

Scab

California Sweet Orange Scab Quarantine Expanded

Daniel CooperCalifornia Corner, Diseases, Regulation

The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) have expanded the area quarantined for sweet orange scab (SOS). The expansion is in the Irvine area of Orange County and in the La Puente area of Los Angeles County in California. QUARANTINE ACTIONS APHIS is expanding …

Mexfly quarantine

California Mexfly Quarantine Expanded

Daniel CooperCalifornia Corner, Pests, Regulation

The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) and the California Department of Food and Agriculture (CDFA) recently expanded the La Mesa Mexican fruit fly (Mexfly) quarantine twice in San Diego County, California. On March 17, APHIS and CDFA expanded the quarantine following the confirmed detections on March 11 of one wild mated female Mexfly and …

California

California Citrus: Grower and Consumer Perspective

Daniel CooperCalifornia Corner

Jesse Silva, vice president of sales at California’s Kings River Packing, recently discussed the spring and summer citrus season from a grower and consumer and perspective on the AgNet West Radio Network. His observations follow. GROWING CONDITIONS AND COSTS This year’s warmer growing conditions have created both challenges and opportunities. Larger fruit sizes and softer textures require careful handling, but …

expanded

California Citrus Greening Quarantine Expanded

Daniel CooperPests, Regulation

The U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) have expanded the area quarantined for citrus greening in California. APHIS established a new quarantined area in the Ramona area of San Diego County of 93 square miles. The agency also expanded the quarantined area in …

Mexfly

Mexfly Quarantine Established and Expanded in California

Daniel CooperCalifornia Corner, Pests, Regulation

Agriculture officials on March 5 established a Mexican fruit fly (Mexfly) quarantine in La Mesa, San Diego County, California, designated the La Mesa quarantine. On March 10 they expanded the quarantine. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) and the California Department of Food and Agriculture (CDFA) established the La Mesa quarantine in response to …

Valencia

California Valencia Orange Forecast

Daniel CooperCalifornia Corner, Crop Forecast

The March forecast for California’s 2025–26 Valencia orange crop is 17 million 40-pound cartons. The forecast is based on the results of the 2025–26 Valencia Orange Objective Measurement Survey, which was conducted from Jan. 10 to Feb. 10. The California Department of Food and Agriculture (CDFA), in cooperation with the U.S. Department of Agriculture National Agricultural Statistics Service, prepared the …

positive

California Psyllids Positive for HLB-Causing Bacterium

Daniel CooperCalifornia Corner, HLB Management, Psyllids

Two adult Asian citrus psyllid (ACP) samples were confirmed positive for Candidatus Liberibacter asiaticus (CLas) in two central California coastal counties on March 10, the Citrus Pest & Disease Prevention Program (CPDPP) reported. CLas is the bacterium that causes HLB. One sample was collected during a routine commodity survey in a commercial citrus grove in the Fillmore area of Ventura …