California Ag Network

Tag: Huanglongbing

  • Huanglongbing Quarantine Boundary Expands in Riverside, SD Counties

    Effective September 11, 2026, the Department is expanding the citrus greening disease boundary in the Murrieta area of Riverside County and into San Diego County (grids 484, 499, and 510). A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/hlb/regulation.html. 

    Also effective September 11, 2026, the Department is expanding the Asian Citrus Psyllid Bulk Citrus Regional Quarantine Zone 6 in these areas to reflect the HLB quarantine boundary expansion. A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/acp/regulation.html.

    Regulated articles and conditions for intrastate movement under the quarantine can be found at Title 3 of the California Code of Regulations (CCR) section 3435 & 3439. Pursuant to 3 CCR § 3435 & 3439, any interested party or local entity may appeal a quarantine area designation. 

    Process to Appeal the Expanded Boundary 

    The appeal must be submitted to the Department in writing and supported by clear and convincing evidence. The appeal must be filed no later than ten (10) working days from the date of this notification. During the pending of the appeal, the designated quarantine boundary under appeal shall remain in effect. 

    Mail Appeals to: CDFA – Citrus Division 1220 N Street Sacramento, CA 95814 

    Electronic Notification of Boundary Changes 

    California Code of Regulation allows interested parties to be notified of quarantine area boundary changes, as well as the opportunity to submit quarantine boundary appeals. If interested in receiving notifications, please sign up for regulatory updates through the email notification at: https://public.govdelivery.com/accounts/CADFA/subscriber/new 

    For questions regarding the regulations or map, please email Raymond Niem (Raymond.Niem@cdfa.ca.gov) or call 916-274-6300. — Story contributed by the California Department of Food and Ag

  • 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

  • Huanglongbing Quarantine Boundary Expands in Riverside, San Diego Counties

    Effective July 29, the Department is expanding the HLB quarantine boundary in the Fallbrook and Rainbow areas of San Diego County and into Riverside County (grids 499 and 500). A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/hlb/regulation.html.

    Also effective July 29, the Department is expanding the Asian Citrus Psyllid Bulk Citrus Regional Quarantine Zone 6 in the both areas to reflect the HLB quarantine boundary expansion. A map of the expanded boundary can be found at https://www.cdfa.ca.gov/citrus/pests_diseases/acp/regulation.html.

    Regulated articles and conditions for intrastate movement under the quarantine can be found at Title 3 of the California Code of Regulations (CCR) section 3435 & 3439. Pursuant to 3 CCR § 3435 & 3439, any interested party or local entity may appeal a quarantine area designation.

    Process to Appeal the Expanded Boundary

    The appeal must be submitted to the Department in writing and supported by clear and convincing evidence. The appeal must be filed no later than ten (10) working days from the date of this notification. During the pending of the appeal, the designated quarantine boundary under appeal shall remain in effect.

    Mail Appeals to: CDFA — Citrus Division 1220 N Street Sacramento, CA 95814

    Electronic Notification of Boundary Changes

    California Code of Regulation allows interested parties to be notified of quarantine area boundary changes, as well as the opportunity to submit quarantine boundary appeals. If interested in receiving notifications, please sign up for regulatory updates through the email notification at: https://public.govdelivery.com/accounts/CADFA/subscriber/new

    For questions regarding the regulations or map, email Raymond Niem (Raymond.Niem@cdfa.ca.gov) or call 916.274.6300.

    — Story contributed to the California Department of Food and Agriculture

  • California Citrus Breeding Program Receives Additional Congressional Support

    California Citrus Mutual (CCM) and Citrus Research Board (CRB) voiced support for the House Committee on Appropriations for including additional funds in the FY 2027 Agriculture Appropriations bill for the citrus breeding program in Parlier.

    Congress 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 will receive $2 million in federal funds annually, in addition to the funding it receives from CRB.

    “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 have been instrumental in getting this program off the ground.”

    “I would like to thank our Appropriators and Committee leadership for their continued support of this vital program,” said CCM Director of Governmental Affairs Jacob Villagomez. “Finding solutions for California-specific growing patterns is an essential tool in fighting HLB for years to come.”

    The California citrus breeding program will focus on fresh market citrus. Funding will go towards research and development of citrus selections suited to California growing regions, changing climatic pressures, consumer taste preferences and resistance to pests and diseases, such as huanglongbing.

    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 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 ongoing appropriations commitment, forward progress continues to be made with the addition of a dedicated scientist, completion of a greenhouse, and future plans for laboratory and office space, and hopefully securing additional ground for further expansion.

    — Story contributed by California Citrus Mutual and Citrus Research Board

  • 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.

  • UC Seeks Consumers to Weigh in on New Method of Controlling Asian Citrus Psyllids

    To understand consumers’ attitudes toward a bioengineered pesticide for citrus crops, University of California Agriculture and Natural Resources researchers are asking for volunteers to participate in focus groups in Riverside, Oakland and Fresno.

    Bacillus thuringiensis, or Bt, is a naturally occurring bacterium being tested to control the spread of Asian citrus psyllid, the small insect that transmits the disease huanglongbing to citrus trees. Both the Asian citrus psyllid and huanglongbing have been found in Southern California backyard citrus trees and threaten to spread throughout the state.

    Huanglongbing, also known as citrus greening disease, is a bacterial infection that stunts citrus trees, reduces their fruit production, deforms and greens the fruit and eventually kills the tree. There is no known cure or effective control.

    The disease has already devastated Florida’s citrus industry, slashing the state’s orange production by 92% between 2005 and 2025, according to Karen Jetter, associate director and project economist at the UC ANR Policy Institute. By the time the magnitude of the problem was revealed, both Asian citrus psyllid, or ACP, and huanglongbing were widespread in Florida.

    “In California, we still have the opportunity to slow the spread of huanglongbing through ACP management,” Jetter said.  “This unique technology is designed to be part of a comprehensive ACP management program, not to replace it.”

    Jetter and Fiona Ogunkoya, survey researcher at the UC ANR Policy Institute, are conducting focus groups to assess consumer attitudes toward an engineered Bt pest control method that targets Asian citrus psyllids, the primary vector of the disease, to stop the spread of huanglongbing.

    The bioengineered pest control strategy, developed in Florida and shown to be effective, uses an engineered citrus tristeza virus to transmit an engineered Bacillus thuringiensis to citrus trees. The Asian citrus psyllid lays eggs on the tender new leaf growth of the trees. After the nymphs hatch, the immature insects consume the modified Bt-infected leaves, become sick and die.

    California citrus growers surveyed by Sandipa Gautam, UC Cooperative Extension integrated pest management citrus advisor, said they are interested in the approach. But they growers are concerned that consumers will not accept fruit grown with this new bioengineered insecticide.

    To find out what consumers think, the researchers will meet with three focus groups, with each session limited to six to eight people to allow all participants time to express their thoughts.

    The 90-minute focus group meetings will be held at UC Cooperative Extension offices in Riverside on March 30 at 6 p.m., in Oakland on April 6 at 2 p.m. and in Fresno on April 8 at 2 p.m. Pizza will be served.

    To participate in a focus group, register for a session at https://forms.gle/QPyUd7QazTLfNdATA. To be eligible, participants must be 18 years of age or older and able to attend the focus group in person. — By UC Agriculture and Natural Resources

  • Using Predators to Counter Asian Citrus Psyllids

    The Asian citrus psyllid is an active threat for growers and the main vector for Huanglongbing disease. These invasive insects have wreaked havoc in Florida and spread to Southern California, but researchers at UC Riverside are finding ways to counter them. Matthew Malcolm from Malcolm Media Ag Publishing interviewed Bodil Cass at the World Ag Expo to discuss the use of predators against psyllids. Watch this quick video and read more in California Fruit & Vegetable Magazine.

    Please thank this video’s sponsor Simplot for their industry support.

  • 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.

  • Asian Citrus Psyllid Infestation in California: A Guide for California Citrus Growers

    SPONSORED CONTENT

    California’s vibrant citrus industry, renowned for its oranges, lemons, and limes, is under threat from the Asian citrus psyllid (Diaphorina citri , ACP). This small invasive pest not only jeopardizes the health of citrus trees but also acts as a carrier of Huanglongbing (HLB), a bacterial disease that causes citrus greening. Here’s what growers need to know about ACP, its impact, and how Kemin Crop Technologies can help with effective botanical solutions to manage and prevent infestations.

    Understanding the Asian Citrus Psyllid

    The Asian citrus psyllid is a sap-sucking insect native to Asia, Africa, and the Saudi Arabian Peninsula. It was first detected in the United States in 2005 in Florida and in California in 2008 and has continued to spread across the major citrus growing regions. This insect’s feeding behavior damages citrus trees by causing leaves to curl and blacken. However, the real threat lies in ACP’s role as a vector for Huanglongbing (HLB). HLB is one of the most devastating diseases affecting citrus crops worldwide. HLB is caused by the bacteria Candidatus Liberibacter asiaticus, which infects the phloem of citrus trees, disrupting nutrient flow. Once a tree is infected, there is no cure, and the disease eventually leads to the tree’s death. Infected trees can be stunted, have reduced fruit yield, blotchy mottled leaves, and produce misshapen, bitter fruit, rendering them unmarketable. The economic and ecological impact of ACP and HLB is profound, putting California’s multibillion-dollar citrus industry at significant risk.

    Identifying an ACP Infestation

    Early detection of ACP infestations is crucial for effective management. Growers should regularly inspect their orchards for the following:

    • Adult Psyllids: Small (3-4 mm long), brown, winged insects perched at a 45-degree angle on leaves.
    • Nymphs: Tiny (0.25-2 mm long), yellowish-orange immature psyllids found on new growth.
    • Honeydew: Sticky substance excreted by psyllids, often leading to sooty mold development.
    • Leaf Curling: Deformed leaves caused by psyllid feeding.

    Regular monitoring and application during ACP’s active growth stages can significantly reduce infestations and aid in limiting the spread of HLB through psyllid vectors.

    Unlock Superior Protection with TetraCURB™ MAX: Kemin’s botanical-oil based Solution

    For growers seeking a sustainable and effective solution, Kemin’s botanical oil-based biopesticide, TetraCURB MAX, offers a promising option. TetraCURB MAX is a rosemary, peppermint, clove and castor oil-based contact miticide-insecticide and repellent specifically designed to target soft-bodied insects like ACP. Its unique composition is formulated from a proprietary blend of essential oils and synergizers to have multiple modes of action that paralyze, suffocate, desiccate, repel, and disrupt the pest’s feeding and reproductive cycles.

    Here are the key benefits of TetraCURB MAX, and excellent tool for citrus growers to leverage:

    • Smart Blend for Maximum Impact: TetraCURB MAX is formulated with a proprietary blend of active ingredients, including castor oil, rosemary oil, clove oil, and peppermint oil. It also contains an adjuvant, soap and emulsifiers ensuring optimal spray contact, spread, and improves active ingredients efficacy without phytotoxicity. This unique combination ensures multiple modes of action, such as neurotoxic effects, contact suffocation, desiccation, and repellency aiding in fast pest knockdown. The multiple modes of action also help to reduce the likelihood of pests developing resistance.
    • Broad-Spectrum: TetraCURB MAX is effective against a range of pests, being specially formulated to target small, soft-bodied insects. ACP fits perfectly into this category, and we see excellent ACP knockdown in 3rd party assays.
    • TetraCURB MAX Kills on contact with a quick knockdown thanks to the smart blend technology.
    • Safety for Labor, Workers, and Consumers: TetraCURB MAX is made from safe-to-use ingredients, providing peace of mind for laborers and workers. Use of TetraCURB MAX requires minimal personal protective equipment (PPE) and allows a zero-hour restricted-entry interval (REI)
    • Minimal Disruption to Harvest Activities: With a zero-day pre-harvest interval (PHI) TetraCURB MAX can be applied at any time during the season, including on the day of harvest.
    • Versatility: TetraCURB MAX is labeled for use on all crops and has no restrictions on the number of applications per growing cycle.
    • Environmental Safety: TetraCURB MAX does not cause phytotoxicity in plants when used according to the label direction.
    • Easy Application: Applying TetraCURB MAX is simple. It can be used as a stand-alone or in a tank mix. Shake well before use, dilute in water, and apply as a foliar spray with standard equipment ensuring full plant coverage until runoff. ​ With a recommended spray volume of 100 gallons per acre and a treatment interval of 5-10 days, TetraCURB MAX fits seamlessly into your crop protection routine.
    • Exemption from Food Tolerance Requirements: These biopesticides are exempt from Maximum Residue Limits (MRLs) in the United States, as the pesticide residue expected to remain on crops after application is minimal.

    Proven Efficacy in Lab and Field Trials

    Recent studies conducted at the University of Florida and in Oviedo, Florida have demonstrated the efficacy of TetraCURB MAX against ACP. First, in lab bioassays, TetraCURB MAX at a 1% rate achieved a 59% mortality rate of ACP nymphs within just three days of the application, outperforming the positive control Spinosad-based product. ​A field trial on sweet orange trees showed that two applications of TetraCURB MAX at 0.5% 21 days apart, significantly reduced the nymphal population by 86%, matching the performance of conventional insecticides like Cyazypyr at 16 fl.oz/100 gal. ​ Download the crop sheet to see the full data set HERE:

    Protecting California’s Citrus Legacy

    The battle against ACP and HLB is ongoing, but with vigilance and innovative solutions like TetraCURB MAX, California’s citrus growers can protect their orchards and ensure the industry’s longevity. By adopting sustainable practices, we can safeguard the future of citrus farming for generations to come.

    Don’t let ACP infestations compromise your citrus yield. ​Add TetraCURB™ MAX to your rotation in an IPM program and experience the benefits of superior pest control. ​

    For more information, visit kemin.com/tetracurbmax or contact your Kemin Sales representative today.