California Ag Network

Category: Pest/Disease Management

  • California Citrus Breeding Program Expanding with Congressional Support

    Today, Presidents of California Citrus Mutual (CCM) and Citrus Research Board (CRB) issued statements applauding Congressional leaders for recently approving additional funds for the new citrus breeding program in Parlier, California. Congress is allocating an additional $500,000 in federal funding on top of the $1 million granted last year to expand the program into California. The program will now receive $1.5 million in federal funds on an annual basis along with the $500,000 that CRB provides the program with annually.

    “CRB was instrumental in developing the concept for the California based program and was also involved in efforts to establish the nationwide program while CCM advocated to secure funding,” said CRB President Marcy Martin. “Our two organizations working together on behalf of the industry has been instrumental in getting this program off the ground.”

    “On behalf of the industry, I would like to thank our congressional leaders and the Committee for their continued support of this program, which will help us find solutions to issues specific to our growers located in California,” said CCM President and CEO Casey Creamer. “I would like to specifically extend our gratitude to Congressmen Costa and Valadao and Senator Padilla for championing the need for this program in D.C.”

    The California citrus breeding program will focus on fresh market citrus. Funding will go towards research and development of high-quality, superior citrus selections well suited to California growing regions, changing climatic pressures, consumer taste preferences, and resistance to pest and diseases, such as huanglongbing (HLB).

    The California program is an expansion of the existing national USDA Agricultural Research Service (ARS) citrus breeding program located in Fort Pierce, Florida, which is focused primarily on varieties that are optimized for Florida growing conditions. Work done through the Florida program has resulted in new varieties with higher yields, increased disease resistance, improved color, and a longer shelf life.

    The Florida and California breeding programs along with the continued support from the University of California citrus breeding program at UC Riverside will work together to deliver results for California based growers.

    The California citrus breeding program is located at the USDA-ARS field station in Parlier. Thanks to funds that have already come in, forward progress continues to be made with the addition of a dedicated scientist, developing plans for construction of a greenhouse and laboratory, and securing additional ground for the program.

    About California Citrus Mutual (CCM)
    CCM is a voluntary, non-profit trade association representing California citrus growers on the economic, regulatory, and political issues that most impact them.

    About the Citrus Research Board (CRB)
    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. More information about the Citrus Research Board may be found at www.citrusresearch.org.

  • USDA Scientists Develop Technology to Reduce Pathogens in Intact Eggs

    Radio Frequency unit. (Photo by Joseph Sites, ARS)

    CDC estimates Salmonella bacteria causes about 1.35 million infections, 26,500 hospitalizations, and 420 deaths in the United States every year. Despite their appearance in everyday meals and snacks, the truth is that raw eggs and egg products can carry Salmonella and cause foodborne illness and outbreaks, and even death, in some circumstances. But researchers at the U.S. Department of Agriculture (USDA) recently found a way to combat this through Radio Frequency (R.F.) technology.

    A simple solution to foodborne pathogens in eggs would be to pasteurize all raw eggs before they are consumed; however, less than 3 percent of commercial eggs are pasteurized in the United States. Conventional thermal pasteurization of intact eggs is usually a long process that involves submerging eggs in hot water for more than 57 minutes to inactivate Salmonella cells. Researchers at the Agricultural Research Service’s (USDA-ARS) Eastern Regional Research Center in Wyndmoor, Pa., used a novel thermal technology that pasteurizes eggs and inactivates Salmonella cells with a short processing time.

    During the study, the water molecules inside the egg rotate and align with the RF instrument’s electric field. This molecular friction causes the liquid inside the egg to heat up quickly and subsequently reduce Salmonella by 99.999 percent within 24 minutes. The R.F.-processed eggs were transferred to the refrigerator and kept at 7°C for seven days to simulate the commercial cold chain temperature.

    “After treatment with the system, no intact Salmonella or sub-lethal Salmonella cell remnants were recovered, and no cell recovery was found in the R.F. – treated eggs when stored at retail refrigerated temperature,” said USDA-ARS Research Food Technologist Daniela Bermudez-Aguirre. “The egg quality, such as the color and other parameters, were also preserved through the processing.”

    This technology has shown several advantages when used in food, all without a negative effect on food quality. Statistics also show that Americans consumed a total amount of 93.1 billion eggs in 2023. So, this is a promising advancement for small farmers or egg processors and can ensure food-safe eggs while minimizing Salmonella. Consumers will also benefit from this technology since it preserves the quality of the eggs that can be used for special markets such as nursing homes, hospitals, or schools.

    ARS researchers will continue to develop this technology’s capabilities and expect it to be commercially available in the near future.

    The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact.

  • Edible Blue-Green Algae to Protect Honey Bees Against Viruses

    Scientists at the United States Department of Agriculture (USDA)’s Agricultural Research Service (ARS) developed an edible antiviral treatment that can be used to protect honey bees against Deformed Wing Virus (DWV) and other viruses, according to a recent study published in Sustainable Agriculture.

    Honey bees are important agricultural pollinators. However, viruses, including DWV, are linked to the deaths of millions of colonies worldwide. DWV, like other viruses, is most often spread by Varroa mites who carry the disease inside them and infect bee colonies. Infection typically causes deformity and death in bees, especially in the pupae and brood. These colony losses devastate beekeeping industries and pose a major risk to agriculture and the global food supply.

    While there are medicines for other bee diseases and parasites, there is currently no treatment available to help beekeepers reduce viruses in their colonies. Nearly all colonies have DWV and can often be infected with multiple viruses at any given time. Effective antiviral treatments could help to improve colony health and survival as well as crop pollination efficiency.

    “We found that engineered algae diets suppressed DWV infection and improved survival in honey bees,” said Vincent Ricigliano, research scientist at the ARS Honey Bee Laboratory in Baton Rouge, Louisiana. “When mixed into bee food, the engineered algae boost the bee’s immune system to fight off the targeted virus.”

    According to Ricigliano, blue-green algae is the “bee’s knees” of bee food additives. Ricigliano and other ARS researchers previously studied blue-green microscopic algae, also known as microalgae, as a potential food source for honey bees. The algae showed promise since it has a nutritional profile that resembles pollen and is scalable to the level of commercial beekeeping.

    “In addition to the nutritional benefits and immune-boosting effects, engineered algae strains have the potential to protect bees against a wide variety of pathogens,” said Ricigliano.

    Blue-green algae grow via photosynthesis and can remove carbon dioxide from the atmosphere, making it an ecologically friendly approach to improve the health of honey bees.

    “This technology represents a potential new class of treatments for honey bees that is highly sustainable and scalable,” said Ricigliano.

    “It can be added directly to supplemental feed without additional processing and easily integrated into beekeepers’ existing management practices. However, there are regulatory considerations that must be addressed before these applications can be fully realized.”

    The researchers filed a patent application for the technology and plan to use variations of it to target additional bee viruses and other pathogens in future studies.

    The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact.

  • Update to ACP and HLB Bulk Citrus Movement Requirements

    Effective March 12, 2024, the Citrus Pest and Disease Prevention Division (CPDPD) has updated the requirements for moving bulk citrus fruit from an Asian citrus psyllid (ACP) quarantine zone to a packer/processor in a Huanglongbing (HLB) quarantine area. Citrus fruit may now be moved from any ACP quarantine zone to an HLB quarantine area for packing or processing without a mitigation, such as a pre-harvest treatment or field cleaning. One mitigation was previously required.

    Listed below are some examples of potential bulk citrus movement that is now allowed without mitigation, per the CPDPD’s Citrus Grower/Grove Manager Information page:

    • Tulare County to HLB quarantine zone in Riverside County
    • Imperial County to HLB quarantine zone in Ventura County
    • Kern County to HLB quarantine zone in San Diego County

    Please note, safeguarding all fruit in transit is still required for all bulk citrus ACP/HLB quarantine movements, and all other quarantine requirements, such as those for invasive fruit fly quarantines, still apply. Trucks must be fully tarped or the vehicle must be fully enclosed.

    In the instance that HLB is detected in new areas, this regulatory update may be revisited and revised by CPDPD.

    For complete information regarding the mitigations required for fruit movement, please visit the CPDPD’s Citrus Grower/Grove Manager Information page.

    For questions regarding citrus fruit movement requirements, please contact your local County Agricultural Commissioner or contact Keith Okasaki at Keith.Okasaki@cdfa.ca.govor 916-274-6300.

  • UCCE Tulare County Assists Pathologists in Survey for Decay Fungus in Prunes

    Recently, extensive wood decay-related limb breakages have been reported in commercial prune orchards in the Sacramento Valley, adversely affecting fruit production and limiting the value of salable firewood upon orchard removal. Several fungal genera such as Phellinus, Rhodoformes, Schizophyllum, Sterum, Trametes, Ceriporia, and Perenoporia have been recognized for wood-decaying activity on California prunes.  Phellinus pomaceus has been the primary organism associated with prune decay symptoms in the Sacramento Valley; however, it is yet unknown whether P. pomaceus is present in southern San Joaquin Valley prune orchards.

    Figure 1: Symptoms of advanced Phellinus pomaceus infection, showing white rot internal decay of heartwood. Scale bars 10 cm.

    Phellinus pomaceus, specific to prunes and other plums, is one of the commonly reported wood-decaying fungi that attack the heartwood (non-functional xylem) of mature trees (Figure 1). It tends to attack the trunk and large-diameter branches, often resulting in broken limbs and the loss of fruit-bearing scaffolds. In fact, older trees are more likely to contain infection by the fungus, and frequent pruning of large branches may increase the probability of infection due to exposure of the internal heartwood. The fungus can be identified based on its fruiting bodies that emerge as conks or shelf-like brackets that are usually hard, woody, and hoof-shaped (Figure 2). Under the right conditions, these fruiting bodies are often perennial and may exhibit a darkened upper surface after several years of development.

    UCCE Tulare County assisted UC Davis researchers from the Department of Plant Pathology in surveying Tulare County prune orchards for presence of P. pomaceus. Laurel Hoffman, a PhD student working under Dave Rizzo, Professor of Plant Pathology, visited our local UCCE Tulare County office, coordinating with Elizabeth Fichtner, UCCE farm advisor, to visit and survey prune orchards for the pathogen. With the assistance of Walter Martinez, Tulare County Ag Technician, and Santosh Bhandari, Assistant Specialist, six local ‘French’ prune orchards were surveyed with data collected on tree canopy status and presence or absence of fruiting bodies associated with decay fungi. Surveyed orchards were all over 15 years old and were in varying states of overall productivity. Samples from putative decay fungi were collected and brought back to UC Davis for genetic sequencing to identify the specimens. A preliminary observation based on the initial survey suggests that the prevalence of putative decay fungi in prune orchards is lower in the southern San Joaquin Valley than in the Sacramento Valley. The presence of P. pomaceus in the southern San Joaquin Valley has not yet been confirmed.

    To date, there are no control measures for management of P. pomaceus. Chemical control strategies are not available for management of this disease. Removal of fruiting bodies may limit sporulation, thus having the potential to slow disease transmission. However, the value of this technique is limited by the ability to remove conks prior to sporulation and conks may be difficult to see, particularly after leaf out. Additionally, if the pathogen is present at a high level in (or near) affected orchards, the removal of conks may not significantly influence the total load of spores at a site. Fruiting body removal would not affect the health of infected trees because they are already colonized by the fungus.

    Most of California’s prunes are sold in the dried fruit market; however, a few orchards are reserved for fresh prune production. After the economic lifespan of prune orchards, trees are removed, generating wood that can either be sold as firewood, or reintroduced to the soil through whole orchard recycling.  Infection with decay fungi such as P. pomaceous may adversely affect fruit production, limit the lifespan of infected trees, and reduce the economic longevity of orchards. — By Santosh Bhandari, Laurel Hoffman & Elizabeth Fichtner, UC Cooperative Extension

  • Efficacy of a Hull Split Spray vs. Sanitation for NOW Control

    Navel orangeworm (NOW) is most effectively controlled with the cultural practice of winter sanitation. Winter shaking almond trees to remove mummy nuts has proven to decrease next year’s NOW damage better than any other approach. The reason for this is clear. NOW overwinters as larvae in mummy nuts left in the tree after harvest and it is in these nuts the population carries over into the next season. Adult moths emerge in spring, mate, and lay eggs on mummies that are still in the trees as the females can’t find the new crop nuts until hull split. The second generation will then put direct pressure on the new crop nuts at hull split and the third generation will chew the nuts up during the harvest period.

    The way almond prices have been going recently, there’s no doubt that everyone is going to have to spend dollars as wisely as possible for the foreseeable future. Although cleaning the trees of mummies during the winter isn’t cheap, it is the method of NOW control where you clearly get the most bang for the buck spent. We’re really playing a numbers game here, and this is one practice that is stacked in our favor by the biology of this pest.

    For example, let’s assume a potential of 50 mummies per tree and 30 of them each have 1 NOW larvae. Half of those are female, and each female lays approximately 85 eggs. At harvest in late July we’re into the third generation, and for arguments sake let’s assume there’s no natural mortality.

    Look at what could theoretically happen to the worm population in one Nonpareil tree with 30 infested over-wintering mummies and no control:

    • 1st generation: 15 females x 85 eggs/female = 1,275 larvae
    • 2nd generation: 1,275/2 (half female) x 85 eggs = 54,188 larvae
    • 3rd generation: 54,188/2 x 85 = 2,302,990 larvae per tree at harvest!!!
                        (Thankfully, there IS natural mortality or else we’d be knee deep in worms!)
    Now, look at the impact of a hull split spray aimed at the second NOW generation. We know that sprays give at best about 60 percent control. This reduces the population but is not nearly as good as sanitation as you will see.
    • 2nd generation: 54,188 larvae x 40% survival after the spray = 21,675 larvae
    • 3rd generation: 21,675/2 x 85 = 921,196 larvae per tree to attack the crop at harvest.
    Now, look at what sanitation does in comparison. Start with the same 30 infested mummies per tree, then winter clean down to 2 mummies per tree. One is female, one is male.
    • 1st generation: 1 female x 85 eggs/female = 85 larvae
    • 2nd generation: 85/2 (half female) x 85 eggs = 3,613 larvae
    • 3rd generation: 3,613 larvae/2 x 85 = 153,531 larvae per tree at harvest.

    (If you can beat the 3rd generation by an early harvest you’re even further ahead.)

    So, a hull split spray reduced the worm population by 60 percent, but sanitation by itself, without spraying, reduced the population by 94 percent! When more NOW larvae make it through the winter, more egg laying will occur next season regardless of what else you do. In relation to the number of mummies left in the tree, expensive chemical treatments next season will only slow the rate of worm damage increase.

    If you have scarce dollars to spend on NOW control, spend them this winter when they will do the most good in a sanitation program. If the entire neighborhood works at this, the positive effect will be multiplied many times over for everyone. If you’ve got neighbors that don’t seem to get it, cleaning your orchard will still be a tremendous help to you. If you have no mummies, the first generation in the spring won’t be able to build up and establish a population in your orchard. You’ll benefit since they’ll have to fly in from the neighbors after hull split before they can begin to hurt your crop.

    Be sure to finish the job by destroying the infested nuts once they’re on the ground. Mow and shred the mummies before March 1st so NOW moths don’t have a chance to emerge. When you’re enjoying mowing during bloom in the spring, take personal satisfaction in seeing the chips and pieces of almond fragments and mangled worm parts fly out from under your mower! — By Joseph Connell, UCCE Farm Advisor Emeritus, Butte County

  • Preventing Bacterial Blast Damage in Almond This Year

    In 2023, the cold, wet weather during bloom and leaf-out resulted in bacterial blast damage in many Sacramento Valley almond orchards. If conditions this year are cold and wet during bloom, we may see a recurrence of blast: make a plan now to keep blast damage to a minimum.

    The Bottom Line:

    • Bacterial blast can be a problem when cold, wet conditions coincide with bloom or leaf-out.
    • Copper resistance is common in the pathogen: spraying copper is ineffective for preventing blast in many orchards.
    • Frost protection is the most economical prevention option and will help prevent damage from both frost and bacterial blast.x
    • The antibiotic kasugamycin (Kasumin®) is effective for preventing blast when applied up to 7 days before cold, wet weather. It has received approval for availability this year under an emergency exemption registration (Section 18) but is not currently labeled for almond under a full registration (Section 3).The Details:

      Pseudomonas syringae pv. syringae (Pseudomonas) is a bacterium which can infect all aboveground parts of an almond tree. If leaves, flowers, or spurs are infected, the resulting disease is bacterial blast. Pseudomonas is ubiquitous in orchards, so bacterial blast is likely to develop whenever environmental conditions are cold and wet, which favors this disease. Pseudomonas is spread by water hitting the trees, either from rain or sprinklers. If this wetting occurs at the same time as frost damage, Pseudomonas can enter the tree through cells damaged by freezing. Trees are especially susceptible to frost damage during bloom and leaf-out, when tender new growth is exposed to cold temperatures.

      Preventing infection by Pseudomonas is the only way to control bacterial blast. Frost protection in an orchard is your best defense and your most inexpensive prevention strategy: if the trees are not damaged by frost, Pseudomonas will not be able to enter the tree to cause disease. As a second line of defense, research has shown that kasugamycin (Kasumin®) is effective for preventing bacterial blast when applied no more than 7 days before cold, wet weather. Note that kasugamycin is currently not labeled for use in almond, but has become available this season due to a Section 18 exemption. If the weather warrants treatment, kasugamycin can be used as a preventative spray up to two times during bloom. For this spray, complete coverage is crucial for control: all tender new growth must be covered in a protective layer of the antibiotic for it to be effective. Any tissue left uncovered will be unprotected.

      What about copper? Current work by UC researchers shows that copper-resistance is common in Pseudomonas throughout the state. Many of the orchards heavily affected by blast in 2023 received multiple dormant sprays containing copper. In some cases, mixing mancozeb with copper may provide some level of control, but research shows that this mixture is not as effective as kasugamycin and the copper can cause phytotoxicity. — By Jaime Ott, UCCE Tehama, Shasta, Glenn, and Butte Counties

      For more information on bacterial blast, check out these articles at sacvalleyorchards.com

      Bacterial blast/canker: What do we know? – an update on the factors predisposing orchards to damage by bacterial blast, and more details about control strategies for bacterial blast

      Bacterial Blast and Canker – a good description of the various symptoms seen with bacterial blast

  • Legislation Introduced to Extend Pierce’s Disease Control Program

    Last week, Assemblywoman Dawn Addis, (D-Morro Bay) introduced AB 1861 to extend a vital program within the California Department of Food and Agriculture (CDFA) that protects California’s picturesque vineyards and our iconic wine industry from deadly disease. This legislation is sponsored by the California Association of Winegrape Growers and Wine Institute.

    “The wine industry is integral to the economic success of the Central Coast and all of California,” said Addis. “I’m proud to author AB 1861 that extends a crucial line of defense for our wine industry against invasive disease. We have a track record of collaboration among State, local, federal government and the industry itself when it comes to battling Pierce’s Disease and the Glassy Winged Sharp Shooter. I’m proud to extend this collaboration and to be part of the on-going success of California’s wine regions.”

    “Over the last 23 years, the Pierce’s Disease Control Program has been fundamental in addressing the challenges posed by Pierce’s Disease and other pests and diseases,” said Natalie Collins, President of the California Association of Winegrape Growers. “We thank Assemblymember Addis for her leadership in authoring this important legislation.”

    “Our collaboration with California’s Department of Food and Agriculture continues to protect our vineyards against Pierce’s Disease and the Glassy-Winged Sharpshooter,” said Robert P. Koch, President and CEO of Wine Institute. “AB 1861 will extend critical research, innovation, and mitigation and prevention efforts to safeguard the health and vitality of our winegrapes against this invasive species. We are grateful for the support of Assemblymember Addis and the California legislature.”

    California’s wine industry stands as a formidable economic force, contributing significantly to the state’s prosperity. California leads the nation in wine production, producing 80 percent of all U.S. wine and generating a staggering $170.5 billion in annual economic activity. With 615,000 acres of winegrapes producing 3.6 million tons, California’s commitment to sustainability shines through, with eighty percent of its wine produced in certified sustainable wineries.

    Growers are all too familiar with the significant threat posed to vineyards by Pierce’s Disease (PD), carried between plants by an insect called the glassy-winged sharpshooter (GWSS). Since the 1990s, GWSS has been one of the most invasive and deadly pests for vineyards. When a vine develops PD, its ability to draw in moisture is hindered and the plant will either die or become unproductive. PD has caused millions of dollars in damage throughout the state.

    To safeguard California’s wine industry and support ongoing research, inspection, and control measures for PD, AB 1861 will extend the Pierce’s Disease Control Program (program) and the PD/GWSS Board from 2026 to 2031. This extension is subject to approval of growers through a

    referendum that would be conducted in 2025. The last PD/GWSS referendum, conducted in 2020, passed with 78 percent approval of California winegrape growers.

    California’s first indication of a severe threat posed by this disease occurred in Temecula in August of 1999, when more than 300 acres of vineyards were infected with PD and had to be destroyed. In response, the Legislature enacted a legislative package that year creating the advisory task force. In 2001, the program was created to fight the spread and find solutions for PD and GWSS.

    The program has demonstrated success in controlling the spread of PD and GWSS due to the collaborative efforts involving federal, state, and local agencies, along with grower-funded research. The program is funded through a combination of federal and industry funds, as well as grape grower assessments. These assessment funds are used for research, outreach, and related activities on PD, GWSS, and other designated pests and diseases of winegrapes.

    The research overseen by the PD/GWSS Board is critical to advancing knowledge, improving practices, and guaranteeing the longevity of the California winegrape industry. The focus of current research projects ranges from investigating pests and diseases to evaluating existing control methods to exploring new promising control strategies.

  • Citrus Industry Guide to Fruit Fly Quarantines

    Over the last several months, a variety of invasive fruit fly detections have triggered quarantines across numerous counties in California. These fruit fly species – including Mediterranean fruit fly, Mexican fruit fly, Oriental fruit fly, Tau fruit fly and Queensland fruit fly – are considered not established in California. Quarantines and their associated regulatory actions are implemented to stop the artificial spread of these pests and thus avoid additional negative impacts to growers and the state’s agriculture and natural resources.

    The Citrus Pest and Disease Prevention Division is working to provide boots-on-the-ground assistance to the California Department of Food and Agriculture’s Plant Health and Pest Prevention Services Division as they lead efforts in eradicating the fruit flies by conducting larval surveys, host fruit removal, delimitation trapping, treatment activities and regulatory actions across the state.

    Fruit fly quarantines are established after a certain number of adult flies are captured within three miles of one another and within one life cycle. Fruit fly quarantines are also established when detections of reproductive populations such as larva, pupae or mated flies are found in an area. These thresholds have already been met in certain areas of the state, including the following areas:

    Counties Currently Impacted by Fruit Fly Quarantines:

    • Oriental fruit fly: Contra Costa, Riverside, Sacramento, San Bernardino and Santa Clara Counties
    • Mediterranean fruit fly: Los Angeles County
    • Tau fruit fly: Los Angeles County
    • Queensland fruit fly: Los Angeles and Ventura Counties

    To review the quarantine maps, regulatory information, pest profile information for various fruit flies and additional resources, please visit https://www.cdfa.ca.gov/plant/PDEP/treatment/index.html

    FAQ: Bulk Citrus Movement Requirements in Fruit Fly Quarantine Zones

    Treatment information & maps can be found here:https://www.cdfa.ca.gov/plant/PDEP/treatment/treatment_maps.html

    Quarantine information on fruit fly species and other invasive pests can be found here: https://www.cdfa.ca.gov/plant/pe/InteriorExclusion/quarantine.html

    Frequently Asked Questions:

    How is a fruit fly quarantine triggered?
    A quarantine is triggered by the number of adult flies captured within three miles of each other and in one life cycle:

    • Mediterranean, Melon, Caribbean Fruit Fly – 2
    • Mexican Fruit Fly – 5
    • Oriental, Guava, Peach Fruit Fly – 6 Rural or 8 Urban
    • All other adult invasive fruit flies (e.g., Queensland Fruit Fly) – 2

    OR

    • SINGLE detection of larva, mated female, or pupae indicating a breeding population.

    How large is the fruit fly quarantine zone(s)?

    There are three main areas to consider within the fruit fly quarantine zone, and each has different requirements for harvest/bulk citrus movement:

    1. The property where the detection occurred
    2. Core Area: A one-half mile radius around the detection
    3. Quarantine Area: A 4.5-mile radius around the detection.

    What steps must growers in these three areas of the quarantine zone follow in order to harvest/move their bulk citrus?
    For properties where the detection occurred and properties within the core area (0.5-mile radius around the detection site), this citrus is not eligible for packing, but may be stored, processed and consumed on the growing site. If properties within the core areas have no fruit fly or life stages detected on the growing grounds, fruit can only be moved for juicing, processing, freezing, etc. under compliance and safeguarding with approval of the receiving county ag commissioner.

    Growers in the quarantine zone, but outside of the core area, may receive regular pre-harvest treatments with approved insecticides, applied at recommended intervals, starting a sufficient time before harvest (but not less than 30 days before harvest and a minimum of 4 treatments) to allow for development of fruit fly egg and larvae. Determination of the pre-harvest treatment window is based on the degree day model for the specific fruit fly. Once treatment has begun, it must continue through the harvest period.

    Have additional questions? Please reach out to your local County Agricultural Commissioner. — California Citrus Pest & Disease Prevention Program

  • New Stanislaus County Ag Commissioner Serves as Liaison Between Farmers and California DPR

    At Malcolm Media’s recent Tree & Vine Expo, event host Matthew Malcolm was pleased to introduce, Linda Pinfold, the new Stanislaus County Ag Commissioner to attendees.  Watch this brief video to get to know Linda and her emphasis on serving and assisting local farmers in navigating the ever-changing pesticide regulatory environment of California.

    Please thank this video’s sponsor Thunder Creek Equipment for their industry support.