California Ag Network

Tag: citrus greening

  • APHIS Expands the Citrus Greening (Huanglongbing) Quarantined Area in California

    The Animal and Plant Health Inspection Service (APHIS), in cooperation with the California Department of Food and Agriculture (CDFA), is expanding the citrus greening (Huanglongbing; HLB) quarantined area in California. APHIS is adding one square mile to the Santa Paula quarantined area in Ventura County, which impacts 151.7 acres of commercial citrus. APHIS is adding 10 square miles to the quarantined area in Riverside and San Diego Counties, which impacts 121.5 acres of commercial citrus. This measure parallels the intrastate quarantine that CDFA established on July 15, 2026. APHIS is taking this action because plant tissue samples from residential properties tested positive for Candidatus Liberibacter asiaticus, the causal agent of HLB.

    APHIS is applying safeguarding measures outlined in 7 Code of Federal Regulations (CFR) 301.76 through 301.76-11 and associated Federal Orders that govern interstate movement of regulated articles from the quarantined areas. This action helps prevent HLB from spreading to areas that are not currently infested.

    For updated maps and details, visit the APHIS Citrus Greening and Asian Citrus Psyllid webpage. APHIS will also publish a notice of this change in the “Federal Register.”

    For additional information contact Abby R. Stilwell at 919-323-6296 or abby.r.stilwell@usda.gov

    — Story contributed by the USDA Animal and Plant Health Inspection Service

  • Citrus Greening Quarantine Expands in Southern California

    Effective immediately, the Animal and Plant Health Inspection Service (APHIS), in cooperation with the California Department of Food and Agriculture (CDFA), is expanding the area quarantined for citrus greening (Huanglongbing), caused by the Asian citrus psyllid, in California. APHIS is establishing a new quarantined area in the Ramona area of San Diego County of 93 square miles and is expanding the quarantined area in the Loma Linda area of San Bernardino and Riverside Counties by 26 square miles. These measures parallel the intrastate quarantines that CDFA established on March 2, and March 6, 2026, respectively. APHIS is taking this action because of citrus greening detections in plant tissue samples collected from residential properties. There are 25.16 acres of commercial citrus impacted by the new Ramona quarantine and 411.47 acres of commercial citrus impacted by the Loma Linda area expansion.

    APHIS is applying safeguarding measures outlined in 7 CFR 301.76 and Federal Orders pertaining to the interstate movement of regulated articles from the quarantined areas in California. This action is necessary to prevent the spread of citrus greening to non-infested areas of the United States.

    The APHIS Citrus Greening webpage contains specific changes to the quarantined areas in California. APHIS will publish a notice of this change in the Federal Register.

  • Ants Protect Deadly Citrus Disease Vector – New Ant Management Tools

    Ants are known to interfere with biological control of key citrus pests because they feast upon the sugary honeydew produced by small insects. One of these key pests is the invasive asian citrus psyllid that vectors the deadly huanglongbing citrus disease. As California growers diligently work to keep this disease out of citrus orchards, effective ant management is a critical component in the game plan. Ivan Milosavljevic from the California Citrus Research Board met with Matthew Malcolm on California Ag Network to discuss some new game-changing control strategies. Watch this brief interview and read more about it in California Fruit & Vegetable Magazine.

  • Funding Available for California Citrus Growers to Fight Asian Citrus Psyllid, Prevent Citrus Disease

    Huanglongbing (HLB), the deadly citrus disease that decimated the Florida citrus industry has shown up in Southern California and is now threatening the nation’s number one citrus state.  HLB is primarily spread by the invasive Asian Citrus Psyllid, so managing this insect is key to preventing the spread of the disease. Pest mitigation practices may be costly, the California Citrus Research Board (CRB) introduced the California Citrus Research and Field Trials program (CA-CRaFT) to help fund commercial growers (both conventional and organic) to implement these practices. CRB representative Ivan Milosavljevic met with Matthew Malcolm on California Ag Network to share details. Watch this brief interview and read more in California Fruit & Vegetable Magazine.

  • CA Detections of Citrus Disease HLB up 160 Percent

    HLB infected Tree

    Stakes at All-Time High for Backyard & Commercial Trees in 2019

    Detections of Huanglongbing (HLB), an incurable plant disease that kills citrus trees, increased by 160 percent in 2018 compared to the previous year, signaling the growing threat to the state’s iconic citrus trees, landscape and economy.

    HLB is spread by a small pest called the Asian citrus psyllid as it feeds on citrus tree leaves. The disease is not dangerous to humans or pets, but it is fatal for citrus trees and has no cure. Once a tree is confirmed with the disease, it must be removed from the property in order to protect neighboring citrus trees.

    The disease was first discovered in California in 2012 in Hacienda Heights. HLB was detected in 269 trees in 2017 and 699 trees in 2018, with a majority of these occurring in Los Angeles and Orange counties. The disease has not yet been detected in a California commercial grove.

    HLB has devastated commercial citrus production in Florida. Over the course of 10 years, Florida’s commercial citrus industry lost $7.8 billion in revenue, 162,200 citrus acres and more than 7,500 jobs due to HLB. Should the disease spread from backyard trees in Southern California to nearby commercial citrus groves, the livelihood of California’s citrus production could impact about 3,900 farmers and 292,000 acres of citrus production in the state. Commercially grown citrus contributes $7 billion in economic impact to the state and employs more than 22,000 individuals.

    “The livelihood of California’s commercial citrus industry and the generations of families it supports is at risk because of HLB,” said Jim Gorden, a citrus grower in the San Joaquin Valley and chair of the Citrus Pest & Disease Prevention Committee. “We are at a crossroads, and we must all work together to do what is necessary to protect our citrus.”

    Asian Citrus Psyllid Adults

    The California Department of Food and Agriculture (CDFA) has established quarantines throughout the state that limit the transport of citrus across state and international lines, and between areas where the psyllid and disease have been found. Additionally, CDFA has agriculture crews canvasing the state to inspect backyard citrus trees for the Asian citrus psyllid and HLB.

    “The Department is committed to our partnership with California’s commercial citrus industry and residential citrus growers to fight HLB,” said Victoria Hornbaker, interim director of the citrus program at CDFA. “With more than half of California residences estimated to have a citrus tree on their property, and California citrus production supporting billions of dollars in our state’s economy, we all play an instrumental role in protecting our citrus.”

    California residents play an important role in protecting the state’s citrus trees. Residents should: 

    • Proactively inspect their citrus trees for the Asian citrus psyllid and HLB monthly, and whenever watering, spraying, pruning or tending trees.
      • Adult Asian citrus psyllids are brown, about one-eighth of an inch long, and feed with their body at a 45-degree angle on citrus leaves.
      • Symptoms of HLB include blotchy and yellowing leaves, premature and excessive fruit drop, lopsided fruit, and bitter, inedible fruit.
    • Call the state’s pest hotline at 800-491-1899 if the pest or disease is spotted.
    • Cooperate with agriculture officials who may ask to inspect or treat their citrus tree.
    • As part of tree maintenance, visit a local nursery or garden center to get advice on products that can help protect citrus trees.
    • When pruning citrus trees, be sure to dry out citrus clippings or double bag them before removing the plant material from the property.
    • Refrain from moving citrus plants, foliage or fruit as doing this may unknowingly spread the pest.

    More information and photos of Asian citrus psyllids and HLB symptoms are available at CaliforniaCitrusThreat.org.

  • NEW STUDY REVEALS CA CITRUS ECONOMIC IMPACT 

    Citrus Research Board Quantifies Industry Importance

        The total economic impact of California’s iconic citrus industry is $7.117 billion according to a new study commissioned by the Citrus Research Board (CRB).

    Bruce Babcock, UC Riverside

    “In updating our economic analysis, we selected a well-known expert, Bruce Babcock, Ph.D., a professor in the School of Public Policy at the University of California, Riverside, to conduct the research. His findings quantified the significant impact of citrus on California’s economic well-being,” said CRB President Gary Schulz.

    According to Babcock, the California citrus industry added $1.695 billion to the state’s Gross Domestic Product (GDP) in 2016. “California citrus is a major contributor to the economic value of the state’s agricultural sector and is much larger than just the value of its sales,” he said. “Estimated full-time equivalent California citrus jobs totaled 21,674 in 2016-17, and estimated wages paid by the industry during that same timeframe totaled $452 million.”

    Babcock added, “The application of management skills and capital equipment to efficiently utilize land and water to produce high-quality citrus also generates upstream and downstream jobs and income that magnify the importance of citrus production beyond its farm value.”

       In 2016-17, the most recent marketing year of data compilation, Babcock found that the total direct value of California citrus production was $3.389 billion. This value generated an additional $1.263 billion in economic activity from related businesses that supplied materials and services to the citrus industry. Layered on top was another $2.464 billion in economic activity generated by household spending income that they received from California’s industry, according to Babcock, thus rendering a total economic impact of $7.117 billion.

    The study revealed that 79 percent of California’s citrus was packed for the fresh market and 21 percent was processed in 2016-17, which is economically significant because fresh market fruit has a higher value than processed fruit.”

    Of further note, California produced about 95 percent of all U.S. mandarins in the most recent reporting season.

    Joel Nelsen, President of the California Citrus Mutual

    California Citrus Mutual President Joel Nelsen commented, “The “wow” factor in this report is something as it relates to gross revenues and positive impact for the state, people and local communities.  This enthusiasm must be tempered by the fact that huanglongbing (HLB) can destroy all this in a matter of a year if the partnerships that exist between the industry and government cannot thwart the spread of this insidious disease.  Just this week, coincidentally, Brazil authorities reported a 20% reduction in fruit volume.  Reading how that would affect our family farmers, employees and the state is sobering.”

    The CRB study also looked at the possible impact of a potential 20 percent reduction in California citrus acreage or yield or a combination of the two that could result from increased costs associated with meeting government regulations, combatting the Asian citrus psyllid (ACP) and warding off the invasion of HLB, a devastating disease that has decimated citrus production in many other growing regions such as Florida. Babcock calculated that such a reduction could cause a loss of 7,350 jobs and $127 million in associated employment income and could reduce California’s GDP by $501 million in direct, indirect and induced impacts. The CRB currently is devoting most of its resources to battling ACP and HLB to help ensure the sustainability of California citrus.

    Babcock is a Fellow of the Agricultural and Applied Economics Association and has won numerous awards for his applied policy research. The economist received his Ph.D. in Agricultural and Resource Economics from the University of California, Berkeley and his Masters and Bachelors degrees from the University of California, Davis.

    The CRB administers the California Citrus Research Program, the grower-funded and grower-directed program established in 1968 under the California Marketing Act as the mechanism enabling the State’s citrus producers to sponsor and support needed research. Read the full report on the “Economic Impact of California’s Citrus Industry” Here.

  • Statewide Citrus Grower Approaches for Controlling ACP & HLB

    Special Thanks to This Video’s Sponsor!

    The deadly HLB spreading asian citrus psyllid (ACP) continues to make its way through citrus orchards all over California, and the industry is going to need to work together to slow the spread of this pest to buy researchers sufficient time to come up with a solution for HLB. Watch this brief interview with UC Entomologist Beth Grafton-Cardwell as she discusses what works for controlling ACP and growers are doing in southern and central California to manage the pest.

  • HLB Detected on Residential Property in Riverside

    The California Department of Food and Agriculture (CDFA) and the United States Department of Agriculture (USDA) have confirmed the detection of the citrus disease known as Huanglongbing (HLB), or citrus greening, in Riverside County. The disease was detected in plant material taken from a grapefruit tree in a residential neighborhood in the city of Riverside near I-215.

    The infected tree has been removed and agriculture officials are moving swiftly on mandatory surveying in an 800-meter area. Mandatory treatments will soon follow. CDFA staff will visit all regulated entities in the quarantine area, including retail and production nurseries and packinghouses. Additionally, local, state and federal agriculture authorities are working together to determine potential implications to the University of California, Riverside, which will fall within the 5-mile quarantine area.

    Riverside County Agricultural Commissioner/Sealer Ruben Arroyo plans to take an aggressive stance on any abandoned groves in the area, and the Citrus Pest & Disease Prevention Program outreach team is already working with the City of Riverside to inform residents of the actions needed to stop HLB’s spread.

    Learn more in the press release shared by Riverside County.

  • California Lands More than $5 Million in USDA Grants for Citrus Greening Research

    Sacramento, Calif., (January 25, 2017) – The USDA’s National Institute of Food and Agriculture (NIFA) has announced four grants totaling more than $13.6 million to combat a scourge on the nation’s citrus industry, citrus greening disease, also known as Huanglongbing (HLB). UC Riverside will receive $5,112,000 of that funding for a program to design and identify bactericides that can cure or suppress HLB.

    “The economic impact of citrus greening disease is measured in the billions,” said NIFA Director Sonny Ramaswamy. “NIFA investments in research are critical measures to help the citrus industry survive and thrive, and to encourage growers to replant with confidence.”

    HLB is currently the most devastating citrus disease worldwide. It was first detected in Florida in 2005 and has since affected all of Florida’s citrus-producing areas leading to a 75 percent decline in Florida’s $9 billion citrus industry. HLB has also been detected in Georgia, Louisiana, South Carolina and Texas, as well as three residential communities in Southern California. Fifteen U.S. States or territories, including California, are under full or partial quarantine due to the presence of the Asian citrus psyllid (ACP), a vector for HLB.

    Since 2009, USDA has invested more than $400 million to address citrus greening, including more than $57 million through the Citrus Disease Research and Extension Program since 2014.  Other projects in the current grant award include:

    • Clemson University, Clemson, South Carolina, $4,274,523
    • Iowa State University, Ames, Iowa, $2,476,099
    • USDA Agricultural Research Service (ARS), Athens, Georgia, $1,821,197

    More information on these projects is available on the NIFA website.

    Information on efforts to control the Asian citrus psyllid and stop HLB in California is available on CDFA’s web site and the California Citrus Threat web site.