California Ag Network

Category: Citrus Industry

  • New, Cross-Sector Work Group will Speed CA’s Shift to Safer Pest Management

    Yesterday, the California Department of Pesticide Regulation and California Department of Food and Agriculture launched a broad new work group to accelerate the systemwide adoption of safer, sustainable pest control practices.

    The 25-member Sustainable Pest Management Work Group includes farmers, community members, university researchers and representatives from commodity groups and the pesticide industry. They are charged with identifying pathways to minimize the use of toxic pesticides and expand the use of integrated pest management practices; better protect public and environmental health; and engage, educate and promote collaboration to achieve these goals.

     “Transitioning away from toxic pesticides requires us to speed up the development of effective alternatives,” said CalEPA Secretary Jared Blumenfeld. “By giving our farmers a suite of integrated pest management tools, we can better protect farmworkers and some of California’s most vulnerable communities. This dynamic task force will give us the roadmap to achieve this bold vision.”

    “California agriculture is recognized not only for its quality and quantity, but also for the sustainable, innovative, forward-thinking way it is grown,” said CDFA Secretary Karen Ross. “Our farmers have been leaders in adopting integrated pest management and partnering with universities and technical assistance providers to meet our high standards for food, environmental and worker safety. This work group represents a broad array of perspectives to inform the next decade of research and development investment and new partnerships to continue the production of nutritious, delicious food and high quality agricultural products with the least impact to our surrounding communities.” 

    Funded in last year’s budget, the group’s work will build upon the recommendations of the Alternatives to Chlorpyrifos Work Group whose 2020 report identified alternatives to the hazardous insecticide and outlined actions to further support agriculture and the health of local communities, farmworkers and the environment. A new status update details additional actions DPR has taken based on the 2020 report, and how DPR and CDFA are working together to provide additional funding to the University of California and California State University to expand integrated pest management research and education. California prohibited virtually all uses of chlorpyrifos as of Dec. 31, 2020.

    The Sustainable Pest Management Work Group is part of the State’s larger commitment to accelerating the transition away from hazardous pesticides. To support the move, Governor Newsom is proposing to fund additional support for the transition by replacing the current flat-fee mill assessment on pesticide sales with a new risk-based tiered mill assessment, where higher toxicity pesticides are assessed a higher fee.

    The members of the Sustainable Pest Management Work Group include:

     

    1. Jenny Broome, Driscoll’s
    2. Don Cameron, Terranova Ranch
    3. Casey Creamer, California Citrus Mutual
    4. Jim Farrar, UC Integrated Pest Management (IPM)
    5. Chris Geiger, City of San Francisco
    6. Kim Harley, UC Berkeley
    7. Lisa Herbert, Sutter County Agricultural Commissioner
    8. Nina Ichikawa, Berkeley Food Institute
    9. Dan Kaiser, Environmental Defense Fund
    10. Susan Kegley, Pesticide Research Institute
    11. Margaret Lloyd, UC Extension – small farm advisor
    12. Suguet Lopez, Líderes Campesinas
    13. Gabriele Ludwig, Almond Board of California
    14. Pam Marrone, Chestnut Bio Advisors, Formerly Marrone Bio Innovations
    15. Nayamin Martinez, Central California Environmental Justice Network
    16. John McKeon, Taylor Farms
    17. Cliff Ohmart, Pest Control Advisor (PCA)
    18. Scott Park, Park Farms
    19. Margaret Reeves, Pesticide Action Network
    20. Taylor Roschen, California Farm Bureau
    21. Sarah Ryan, Environmental Director Big Valley Band of Pomo Indians
    22. Daniel Sonke, Campbell Soup Company
    23. Paul Walgenbach, Bayer
    24. Ron Whitehurst, Pest Control Advisor (PCA)
    25. Houston Wilson, UC Organic Agriculture Institute

  • Valencia Orange Production Forecast At 20 Million Cartons

    The March 2020-21 Valencia orange forecast is 20.0 million cartons. This forecast was based on the results of the 2020-21 Valencia Orange Objective Measurement (O.M.) Survey, which was conducted from January 11 to February 28, 2021. Estimated fruit set per tree, fruit diameter, trees per acre, bearing acreage, and oranges per carton were used in the statistical models estimating production.

    The season had experienced scattered precipitation in some areas but mainly warm and dry conditions in January and February. Survey data indicated an average fruit set per tree of 545, a 2.7% decrease from the previous year and slightly below the five-year average. The average March 1 diameter was 2.552 inches, up 3.3% from the previous year and slightly above the five-year average of 2.529.

    SURVEY HISTORY

    A Valencia Orange Objective Measurement Survey was conducted from the 1985-86 to 1993-94 seasons before suspension due to a lack of funding. The survey has been conducted since it was reinstated for the 1999-00 season, with the exception of the 2006-07 season due to a substantial freeze. The data from the first three years after the survey was reinstated were used for research purposes in developing crop- estimating models.

    SURVEY SAMPLE

    A sample of 379 Valencia orange groves were randomly selected proportional to acreage, county, and variety representation in the state, with 334 of these groves being utilized in this survey. Once a grove was randomly chosen and grower permission was granted, two trees were randomly selected for each grove. For each randomly selected tree, its trunk was measured along with all connected branches. A random number table was then used to select a branch, and then all connected branches from the randomly-selected branch were measured.

    This process was repeated until a branch was reached with no significant limbs beyond it. This randomly-selected branch, called the terminal branch, was then closely inspected to count all fruit connected to it, as well as all of the fruit along the path from the trunk to the terminal branch. Since each selected path has a probability of selection associated with it, a probability- based method was then applied to estimate a fruit count for the entire tree.

    In the last week of the survey period, fruit diameter measurements were collected on the right quadrant of four trees surrounding the two trees of every third sampled grove. These measurements were used to estimate an average fruit diameter per tree. The sampled groves were primarily in the top Valencia orange producing counties of Tulare, Kern, Fresno, Ventura, and San Diego.

  • CA Prune Board Addresses Non-Tariff Barriers for Nuts & Dried Fruit

    As the world leader in prune exports, the California Prune Board is preemptively addressing issues that affect the trade of dried fruits and nuts with a three-year project focused on preserving the use of sulfuryl fluoride. With the support of the Foreign Agriculture Services arm of USDA, the California Prune Board (CPB) has secured funding to lead a Technical Assistance for Specialty Crops (TASC) program titled “Preserving sulfuryl fluoride for dried fruit exports to the European Union.”

    “This project hits on all the major non-tariff barriers,” says Gary Obenauf, CPB Production Research Coordinator and lead on the TASC project. “Exports of nuts and dried fruits require reliable measures that ensure consumers around the world are receiving a safe product and this project is paramount in gathering the information needed, enabling California Prunes and other commodities to retain and expand export markets.”

    While the project specifically investigates the voids in residue data associated with the use of sulfuryl fluoride for treating U.S. dried fruit and tree nuts, the research ultimately addresses the stringent criteria to limit emissions for continued and optimal sulfuryl fluoride use in all export markets for a variety of commodities. The study is being conducted by top experts in their fields from Stanford, Yale, USDA’s Agricultural Research Service (ARS), University of California, and DFA of California.

    “Global trade interest in eliminating greenhouse gas emissions is growing, and we’re getting asked about sulfuryl fluoride use in several markets,” stated Spencer Walse, a research chemist for ARS. “This project provides an opportunity to continue sulfuryl fluoride use globally and preserves the quality of products while maintaining food safety and security. If we don’t protect the use of sulfuryl fluoride, the ability to export to various countries, including the EU, diminishes.”

    With new use patterns that need to be reflected globally, efficacy data is generated for market access into new export opportunities. Many countries, including India and Australia, require residue data to accompany the efficacy data to ensure consumer safety.

    “We studied methyl bromide decades ago and found the use patterns didn’t apply, so we had to adapt for sulfuryl fluoride,” added Obenauf. “This project allows us to update regulatory use patterns which have evolved since we started this work.”

    Phytosanitary techniques are vital to the export industry. The benefits of updating regulatory information through this research and gaining data on sulfuryl fluoride scrubbing extend far past the dried fruit and nut industries and will allow continued use of the gas globally.

    California is the world’s largest producer of prunes providing approximately 40 percent of the world’s supply and over 90 percent of the U.S. supply. Today, there are more than 40,000 bearing acres of California Prune orchards concentrated in the Sacramento and San Joaquin Valleys.

  • New Study Indicates High Prune Diet Prevents Bone Loss After Traumatic Injury

    As part of the California Prune industry’s long-time commitment to world-class nutrition research, a new, peer-reviewed animal study shows a diet high in California Prunes completely prevents bone loss associated with spinal cord injury (SCI), while also restoring a fraction of the bone lost after SCI.

    Individuals who suffer spinal cord injury (SCI) are prone to extremely rapid bone loss. This leads to a significant increase in the risk of fractures, osteoporosis, and overall mortality. Results of this New animal study conducted by San Francisco Veterans Affairs Medical Center, Department of Veterans Affairs and the Department of Orthopedic Surgery show California Prunes may be able to help.

    “Healthy bones come from the right exercise and diet,” says Leslie Bonci, registered dietitian and consultant for the California Prune Board. “California Prunes are particularly rich in bone-building minerals. Not only does the fruit provide boron and manganese, but also Vitamin K — another nutrient that is fundamental for bone mineralization.”

    The study finds Prunes, in their Dried Plum version, mitigates Spinal Cord Injury-induced Bone Loss in Mice, was published in the Journal of the Orthopedic Research Society. The research was led by Halloran and Xuhui Liu, M.D., San Francisco Veterans Affairs Medical Center, Department of Veterans Affairs and the Department of Orthopedic Surgery, UCSF. In a serving of California Prunes, you can find potassium, Vitamin K, manganese, boron, and fiber.

    The researchers conducted two separate experiments. In a prevention experiment, they looked at dietary supplementation with dried plum for mitigating the loss of bone induced by SCI. Then, in a recovery experiment, they examined if a dried plum diet could restore bone lost after SCI.

    “We are seeing an exciting ‘prune effect’ on bones,” said Bernard Halloran, Ph.D., Professor Emeritus, University of California – San Francisco (UCSF). “In a variety of unique research scenarios, prunes are consistently associated with a favorable bone response.”

    The new study findings build on a growing body of research that shows a link between positive bone health response and California Prunes in post-menopausal women, along with research that shows a similar favorable bone response among those exposed to radiation – such as astronauts in space.

    Additional nutrition research studies are now underway adding to the investment in scientifically-sound evidence about the health benefits of prunes. The research pipeline includes the largest clinical trial ever undertaken by the California Prune industry that is looking at how California Prunes influence the microbiota and inflammation reduction, as well as a first-of-its-kind study that is evaluating the impact of California Prunes on the bone health of men. More studies are examining how California Prunes effect the fracture-healing process and the fruit’s impact on the bone health of younger women who are taking oral contraceptives.

    ABOUT THE CALIFORNIA PRUNE BOARD

    Created in 1952, The California Prune Board aims to amplify the premium positioning and top-of-mind awareness of California Prunes through advertising, public relations, promotion, nutrition research, crop management and sustainability research, and issues management. The California Prune Board represents approximately 800 prune growers and 28 prune, juice, and ingredient handlers under the authority of the California Secretary of Food and Agriculture.

  • Novel Treatment Causes Killer Citrus Disease to Leak & Die

    New research affirms a unique peptide found in an Australian plant can destroy the No. 1 killer of citrus trees worldwide and help prevent infection. Huanglongbing, HLB, or citrus greening has multiple names, but one ultimate result: bitter and worthless citrus fruits. It has wiped out citrus orchards across the globe, causing billions in annual production losses.

    Untreated citrus plants on the left, as compared to treated ones on the right. (Hailing Jin/UCR)

    All commercially important citrus varieties are susceptible to it, and there is no effective tool to treat HLB-positive trees, or to prevent new infections. However, new UC Riverside research shows that a naturally occurring peptide found in HLB-tolerant citrus relatives, such as Australian finger lime, can not only kill the bacteria that causes the disease, it can also activate the plant’s own immune system to inhibit new HLB infection. Few treatments can do both.

    Research demonstrating the effectiveness of the peptide in greenhouse experiments has just been published in the Proceedings of the National Academy of Sciences.

    The disease is caused by a bacterium called CLas that is transmitted to trees by a flying insect. One of the most effective ways to treat it may be through the use of this antimicrobial peptide found in Australian finger lime, a fruit that is a close relative of citrus plants.

    “The peptide’s corkscrew-like helix structure can quickly puncture the bacterium, causing it to leak fluid and die within half an hour, much faster than antibiotics,” explained Hailing Jin, the UCR geneticist who led the research.

    When the research team injected the peptide into plants already sick with HLB, the plants survived and grew healthy new shoots. Infected plants that went untreated became sicker and some eventually died.

    Arrows point to areas of fluid leakage from the bacterial cell after treatment with the antimicrobial peptide. (Hailing Jin/UCR)

    “The treated trees had very low bacteria counts, and one had no detectable bacteria anymore,” Jin said. “This shows the peptide can rescue infected plants, which is important as so many trees are already positive.”

    The team also tested applying the peptide by spraying it. For this experiment, researchers took healthy sweet orange trees and infected them with HLB-positive citrus psyllids — the insect that transmits CLas.

    After spraying at regular intervals, only three of 10 treated trees tested positive for the disease, and none of them died. By comparison, nine of 10 untreated trees became positive, and four of them died.

    In addition to its efficacy against the bacterium, the stable anti-microbial peptide, or SAMP, offers a number of benefits over current control methods. For one, as the name implies, it remains stable and active even when used in 130-degree heat, unlike most antibiotic sprays that are heat sensitive — an important attribute for citrus orchards in hot climates like Florida and parts of California.

    In addition, the peptide is much safer for the environment than other synthetic treatments. “Because it’s in the finger lime fruit, people have eaten this peptide for hundreds of years,” Jin said.

    Hailing Jin, research leading UC Riverside geneticist

    Researchers also identified that one half of the peptide’s helix structure is responsible for most of its antimicrobial activity. Since it is only necessary to synthesize half the peptide, this is likely to reduce the cost of large-scale manufacturing.

    The SAMP technology has already been licensed by Invaio Sciences, whose proprietary injection technology will further enhance the treatment.

    Following the successful greenhouse experiments, the researchers have started field tests of the peptides in Florida. They are also studying whether the peptide can inhibit diseases caused by the same family of bacteria that affect other crops, such as potato and tomato.

    “The potential for this discovery to solve such devastating problems with our food supply is extremely exciting,” Jin said. — By Jules Bernstein, UC Riverside

  • Yellow Leaves In Spring Indicative Of Need To Adjust Nutrient Management

    California Avocado Commission — In spring, as California avocado trees begin to bloom, growers often report seeing yellow leaves at the ends of branches of otherwise healthy trees. Dr. Danny Klittich, of Redox, recently posted an online article about the yellowing of leaves in spring, what this indicates, and what growers can do to remedy the situation.

    When avocado trees begin producing flowers, the blooms become major sinks for nutrients — gathering the nutrients they need to set and retain fruit. The timing of fruit development also coincides with the cooler months of the California avocado growing season, when growers tend to fertilize less and the soils, adapting to cooler temperatures, tend to provide less nutrition to the trees. Thus, trees begin to reallocate nutrients from the roots and leaves to the more important task of developing blooms for fruit set. With nutrients reallocated, leaves on the ends of branches may begin to yellow.

    According to research, nitrogen, zinc and iron leaf concentrations were lower in chlorotic (yellow) leaves. This makes sense when you consider the importance of each of these to bloom and fruit development. In general, Dr. Klittich recommends that trees should yield a fall tissue sample of 2.5 – 2.7% nitrogen for higher yields. This level provides the tree with an adequate reservoir for bloom development.

    Dr. Klittich recommends growers complete the following to improve yield potential.

    • Early bud development — During cauliflower bloom and floral elongation, apply nitrogen, zinc, iron, boron and calcium.
    • Bloom spray — Nutrient applications should provide calcium, zinc, iron and amino acids and can be made from cauliflower stage through full bloom
    • Fruit set — Weekly applications should be designed to support fruit set and development

    To view Dr. Klittich’s specific product and dosage recommendations, as well as an informative video concerning avocado bloom strategies, visit his latest online article.

  • Preventing & Managing Wind Damage In CA Avocado Groves

    California Avocado Commission — When it comes to potential wind damage, California avocado growers typically face two different scenarios: chronic wind exposure or severe wind events.

    Avocado trees housed in windy portions of a grove are often stunted and underperform production wise.  They also may be water stressed, which will impact the uptake of minerals, and their roots may be stressed due to consistent rocking caused by the wind. The only remedy, in these cases, is to create a wind shelter that minimizes wind exposure.

    In windy groves, fruit often will exhibit markings that can be mistaken for diseases or pest damage. For example, black marks caused by wind may be mistaken for anthracnose post harvest rot or russet scars may lead growers to suspect their trees have persea thrips damage. While some superficial wind damage may not affect the quality of the fruit – particularly if that damage occurs when the fruit is young – some wind damage can lead to large scars or “alligator skin” that are more impactful to fruit quality.

    Severe wind events often blow avocado trees over. In these instances, unless the tree is very young, consider removing the tree. Attempting to move the tree back into an upright position can further damage the roots. If the fallen trees looks like it will recover, it can remain where it is. New shoots may emerge from the trunk and form the structure for a new tree. If this occurs, large, old branches can be removed later as the new portion of the tree takes shape. If you do remove the tree, avoid planting a new tree close to where the old tree existed unless you remove the stump and sterilize the soil. The roots from the old tree could become infected by Phytophthora root rot and thus infect a new tree.

    Strong wind events also can break limbs or blow fruit off the trees. After a storm, windfall should be properly disposed of and broken branches removed.  It is important to monitor trees after severe storms, paying close attention to signs of wilting that may indicate stressed roots or a broken branch that was missed during earlier assessments.

    For more information about preventing and managing wind damage, visit the California Avocado Commission’s wind protection online library.

  • California Avocado Commission Referendum Announced

    Every five years the California Department of Food and Agriculture holds a state-mandated referendum vote to provide California avocado growers the opportunity to determine whether the California Avocado Commission will be reapproved to continue for the next five years.

    “The referendum process is a vital component of the law that established the California Avocado Commission,” said Rob Grether, chairman of the CAC board of directors. “It provides growers the opportunity to cast their vote on continuing the operations of the organization.”

    Ballots will be mailed to eligible California avocado commercial producers on February 15, 2021 and must be postmarked and sent to CDFA for tallying by March 16, 2021. Eligible commercial producers who do not receive a ballot should contact the CDFA Marketing Branch staff at 916-900-5018. Results are expected to be tallied by CDFA and announced no later than March 31, 2021.

    “The California Avocado Commission exists to support California avocado growers and is governed by a board of directors comprised of their peers to ensure good stewardship of grower funds,” said CAC President Tom Bellamore.

    The Commission focuses on fostering grower viability by building demand for California avocados at a price premium and increasing the fruit’s perceived value, preference and loyalty. About 70% of CAC’s current budget goes toward marketing, which includes developing strategic, targeted programs with retailers and foodservice operators. Other key activities include advocating for California avocado growers on issues such as water, trade and export, supporting production research and grower education.

    There have been eight reaffirming referenda since the establishment of the California Avocado Commission in 1978.

  • Drier La Niña Winter Conditions Can Contribute To Sudden Freezes

    California Avocado Commission — Although the California avocado growing regions are expected to experience a moderate La Niña phase with warmer average temperatures through spring 2021, the lower rainfall amounts associated with this climate phase can lead to sudden cold spells or freezes. As Dr. Ben Faber noted in a recent blog post, some of California’s most severe freezes have occurred during weak La Niña phases.

    Advection and radiation freezes pose the most threat to California avocado groves. Advection freezes are caused by the movement of arctic air into the region. Radiation freezes occur at night when clear skies and calm conditions are present that allow cold pockets of air to settle in low areas of the grove.

    To prepare for potential frosts or freezes, it’s important to remember that different prevention measures may be used for a frost versus a freeze. A frost is caused when objects cool at night and radiate their heat loss, thus chilling the surrounding air. In Southern California, warm air is typically close to the ground due to a low ceiling, thus causing a temperature inversion that protects orchards. However, windy conditions can disrupt this inversion and press cold air to the ground. In comparison, a freeze occurs when cold air moves in and the air temperature decreases at both high and low levels.

    • To prevent damage when cold weather events are in the forecast, consider the following.
    • To protect against frost or freeze, orchard heaters can be used to distribute heat. The downside of heaters is the cost of running them and possible fire hazards.
    • Wind machines should only be used in frost, not freeze, conditions and should not be used when it is windy. This economical option can be paired with orchard heaters to improve effectiveness.
    • If frost threatens and no temperature inversion is present, the best practice is to run microsprinklers during the day and turn off the water prior to sunset. If the temperature drops below freezing, restart the water and run it until sunrise. If ice forms on the fruit or leaves, heat will be released as the ice melts and protect the plants.
    • If watering the entire grove prior to a cold weather event is cost prohibitive, it is recommended that growers opt to water only those portions of their groves that tend to be coldest.

    If your grove is affected by a frost/freeze event, please view Post-freeze Avocado Grove Management on the California Avocado Commission’s website. For more complete information, visit the Commission’s online library of frost/freeze protection articles.

  • CDFA Seeking New Grower Representative for Citrus Pest & Disease Prevention Committee

    The California Department of Food and Agriculture (CDFA) is seeking a grower representative with operations in the Fresno County area to sit as a member on the Citrus Pest and Disease Prevention Committee. The Committee advises the CDFA Secretary on activities associated with the statewide citrus specific pest and disease work plan that includes – but is not limited to – outreach and education programs and programs for surveying, detecting, analyzing, and treating pests and diseases specific to citrus.

    Committee members receive no compensation but are entitled to payment of necessary travel expenses in accordance with the rules of the Department of Personnel Administration. The term for one grower representative from Fresno County expires on Sept. 30, 2023. Applicants should have an interest in agriculture and citrus pest and disease prevention. Individuals interested in being considered for a committee appointment should send a resume by Feb. 15, 2021 to the California Department of Food and Agriculture, Citrus Pest and Disease Prevention Division, 1220 N Street, Sacramento, California 95814, Attention: David Gutierrez.

    For additional information on the committee vacancy, contact: David Gutierrez, Branch Chief, Citrus Pest and Disease Prevention Division at (916) 274-6300, or e-mail David.Gutierrez@cdfa.ca.gov.