California Ag Network

Category: Pest/Disease Management

  • New Pesticide Laws & Regs Now Taking Effect in California

    If you missed the Annual Tree & Vine Expo, Marline Azevedo with the Stanislaus County Ag Commissioner’s office provided an update on changes in laws and regulations for growers moving into 2018. Watch her brief interview as she describes two key changes in Chlorpyrifos permit conditions & pesticide use around school sites.

  • CA Citrus Clonal Protection Program Plays a Key Role in Fighting HLB

    As the CA citrus industry works to fight the HLB disease carrying Asian Citrus Psyllid from destroying the industry, the California Citrus Clonal Protection Program is playing a key role in preparing the industry for battle. Watch this interview with Georgios Vidalakis, Director of the program as he explains. Read more in California Fresh Fruit Magazine.

  • Ag Leaders, Scientists Set Priorities to Prevent Invasive Pest Threats to the Environment and Economy

    Sacramento, Calif., (January 18, 2018) – The gypsy moth, an interloper from Europe and Asia, is threatening California’s majestic oaks in Ventura County.

    Invasive desert knapweed, which comes from Africa, has made its first North American appearance in in California’s Anza-Borrego Desert, where it has started to crowd out native plants.

    Asian citrus psyllids are slowly spreading the devastating huanglongbing disease in Southern California citrus.

    River rats from South America, called nutrias, are munching voraciously on wetland plants in some areas of Stanislaus, Merced and Fresno counties.

    These are just a few of the insects, weeds, animals and diseases that have entered the state of California from elsewhere on the globe, causing tremendous ecological damage and huge economic losses to agricultural crops, which ultimately affect every resident of California.

    Based on historical data, a new invertebrate species establishes itself in California about every six weeks, on average. They don’t all become serious pest problems, but many evade eradication efforts, disrupt carefully balanced integrated pest management programs, hijack sensitive ecosystems, and spoil valued recreational resources and urban landscapes.

    A diverse group of university scientists, federal and state government representatives, county agricultural commissioners and non-profit organization leaders who are battling these pests converged at a summit in the state capitol Jan. 11 and 12 to coordinate their efforts, pool intellectual resources, and plot a strategy for protecting agricultural crops, natural resources, unique ecological communities, cityscapes and residential neighborhoods.

    “We are a big, beautiful, special place, blessed with great weather and diverse geography,” said California Department of Food and Agriculture Secretary Karen Ross at the summit. “That means a lot to our many visitors – including pests.”

    Glenda Humiston, vice president of UC Agriculture and Natural Resources, which co-sponsored the summit, outlined the goals.

    Glenda Humiston, vice president of UC Agriculture and Natural Resources, said research is a fundamental component of the fight against damaging invasive species.

    “We know that collectively, we have the tools and expertise to prevent invasive species from entering California, spreading and becoming established,” Humiston said. “I am so pleased with the numbers of people here today, and the expertise that you bring.”

    A fundamental component of the fight against damaging invasive species is research, Humiston said, adding that the European grapevine moth in an apt example. The pest was detected in California’s wine country in 2009, and later found as far south as Fresno County. A multi-agency collaboration responded quickly.

    UC ANR academics studied the moth’s biology, life cycle, host range and proven management practices. They developed a pest management program that relied on mating disruption with pheromones and application of carefully timed insecticides. In short order, the moth population plummeted, and the state was declared free of European grapevine moth, lifting a quarantine, enhancing farmers’ ability to export its product, and preserving the communities’ economic wellbeing.

    “This multi-agency collaboration contributed to a successful, science-based response plan to a serious pest threat,” Humiston said.

    She noted, however, that prevention is the best option.

    “This is critical,” Humiston said. “Once the pests are here, they cost us millions upon millions of dollars to manage, not to mention the devastation and destruction inflicted on our crops, natural resources and the damage to local economies.”

    In 2010, CDFA created a strategic framework for addressing California’s ongoing invasive pest problems and potential future introductions. Successful implementation of the framework requires partnerships involving government from the state to local levels, the agriculture industry and commodity groups, non-governmental organizations committed to the environment, and researchers at UC and other universities.

    UC Cooperative Extension advisor emeritus John Kabashima led a break out session on arthropods during the summit.

    UC Cooperative Extension advisor emeritus John Kabashima was instrumental in bringing the summit to fruition. Kabashima, who retired in 2015, continues to lead a battle against invasive shot hole borer pests in Southern California. The insects, originally from Asia, are killing thousands of Southern California trees, and have the potential to kill millions of trees in urban areas, natural areas and even on farms in parts of the state as far north as Sacramento.

    “We convened this meeting to bring together experts in the field and people who are feeling the impacts,” Kabashima said. “We’re trying to start a 21st century invasive pest program that would then be implemented and funded to address the urgent issues before they cause any more devastation.”

    At the end of the two-day summit, the participants voted to decide the most pressing issues and best strategies to take forward to their agencies, coalitions, research groups, legislators and constituents. Key strategies that emerged were:

    • Analyze the economic impacts of invasive species management and the cost of “doing nothing.”
    • Develop and maintain statewide surveys and map high-risk surveys.
    • Increase funding to study invasive species’ biology.
    • Create a standing rapid response workgroup to guide response to new invasive species. Fund a rapid response emergency fund.
    • Enact regulations to control high-risk vectors, such as soil, green waste, gravel, forage, straw and firewood.
    • Formalize the Invasive Species Council of California (ISCC) and the California Invasive Species Advisory Committee (CISAC).

    Mark Hoddle, UC Cooperative Extension biological control specialist and director of the Center for Invasive Species Research at UC Riverside, said the summit was a valuable part of the ongoing battle against invasive pests.

    Summit participants prepare to vote on most pressing invasive species’ issues and best management strategies.

    “It’s good to see the number of agencies and organizations involved with invasive species issues,” Hoddle said. “I’m impressed with the energy in coming up with these priority lists.”

    Summit outcomes will include sending recommended action items to the Legislature for funding consideration.

    “Without financial support, many of the management tools that prevent unwanted incursions, find and monitor incipient pest populations, and develop sustainable, cost-effective management programs won’t be possible,” Hoddle said.

  • Mexican Fruit Fly Quarantine In Portion Of San Diego County

    Sacramento, Calif., (January 8, 2018) – A portion of San Diego County has been placed under quarantine for the Mexican fruit fly following the detection of seven flies within the City of Encinitas.  The United States Department of Agriculture (USDA), the San Diego County Agricultural Commissioner, and the California Department of Food and Agriculture (CDFA) are working collaboratively on this project.

    The quarantine area in San Diego County measures 65 square miles, bordered on the north by McClellan Palomar Airport; on the south by San Dieguito Road; on the west by the Pacific Ocean; and on the east by the San Dieguito River.  A link to the quarantine map may be found here:www.cdfa.ca.gov/plant/mexfly/regulation.html.

    Sterile male Mexican fruit flies will be released in the area as part of the eradication effort.  The release rate will be 325,000 males per square mile per week in an area up to 50 square miles around the infestation.  Sterile male flies mate with fertile female flies in the natural environment but produce no offspring.  The Mexican fruit fly population decreases as the wild flies reach the end of their natural life span with no offspring to replace them, ultimately resulting in the eradication of the pest.  In addition, properties within 200 meters of detections are being treated with an organic formulation of Spinosad, which originates from naturally-occurring bacteria, in order to remove any mated female fruit flies and reduce the density of the population.

    The quarantine will affect anyone who grows, sells, or gives fruit or plants away to others. This includes growers, wholesalers, and retailers of susceptible fruit in the area as well as nurseries that grow and sell Mexican fruit fly host plants. All host fruit grown within the quarantine area must be treated or processed before being sold. All nursey plants with host fruit must be treated or placed off sale. The quarantine will also affect local residents – home gardeners are urged to consume homegrown produce on site and not move it from their property.  These actions protect against the spread of the infestation to nearby regions where it could affect California’s food supply and our backyard gardens and landscapes.

    The Mexican fruit fly can lay their eggs in and infest more than 50 types of fruits and vegetables, causing severe impacts on California agricultural exports and backyard gardens alike.  For more information on the pest, please see the pest profile at: www.cdfa.ca.gov/plant/go/MexFly.  Residents who believe their fruits and vegetables are infested with fruit fly larvae are encouraged to call the state’s toll-free Pest Hotline at 1-800-491-1899.

    The eradication approach used in the Encinitas area of San Diego County is the standard program used by CDFA and it’s the safest, most effective and efficient response program available.

    While fruit flies and other invasive species that threaten California’s crops and natural environment are sometimes detected in agricultural areas, the vast majority are found in urban and suburban communities.  The most common pathway for these invasive species to enter our state is by “hitchhiking” in fruits and vegetables brought back illegally by travelers as they return from infested regions of the world.  To help protect California’s agriculture and natural resources, CDFA urges travelers to follow the Don’t Pack a Pest program guidelines (www.dontpackapest.com).

  • UCCE Verifies Efficacy of Mating Disruption Technology for Navel Orangeworm Control

    Mating disruption technology for Navel Orangeworm Control has been around for a while now, but today there are a lot more products on the market available to tree nut growers. UCCE Entomology Farm Advisor in Kern County, David Haviland shared in an interview with California Ag Network that his research trials prove that not only is mating disruption technology a worthwhile investment for growers, but growers have several effective options to choose from. Watch this interview and read more about it in Pacific Nut Producer Magazine.

    Calagnet & YARA
    Special thanks to this video’s sponsor!

  • Tests Show Low or No Pesticide Levels in Most Fruits and Vegetables in California

    Sacramento, Calif., (December 29, 2017) – Tests on produce collected by the California Department of Pesticide Regulation (DPR) indicate that the vast majority of fruits and vegetables available for sale in California meet stringent pesticide safety standards. During its 2016 survey, DPR found 96 percent of tested California-grown produce had little or no pesticide residues.

    The findings are included in DPR’s just released 2016 Pesticide Residues in Fresh Produce report.

    “Once again this report shows that California consumers can have high confidence in the fresh fruits and vegetables available to them at stores.” said Brian Leahy, Director of DPR. “A strong regulatory program gives guidance to the proficient farmers and pesticide applicators that grow the fruits and vegetables that are part of a healthy diet.”

    The report is based on year-round collection of 3,585 samples of produce, from 27 different countries, including those labeled as “organic”. California grown produce accounted for 24 percent of the samples tested. DPR scientists and staff sampled produce from various grocery stores, farmers’ markets, food distribution centers, and other outlets throughout California.

    The U.S. Environmental Protection Agency (U.S. EPA) sets levels for the maximum amounts of pesticide residue that can be present on fruits and vegetables, called a “tolerance”. It is a violation if any residue exceeds the tolerance for the specific fruit or vegetable, or if a pesticide is detected for which no tolerance has been established. However, a sample with an illegal pesticide residue does not necessarily indicate a potential health concern

    In 2016, after public concern arose about glyphosate DPR conducted a pilot project to screen fresh produce for glyphosate residues. This herbicide is widely used in agriculture. The testing found no illegal glyphosate residues on any of the produce tested.

    The produce is tested for nearly 400 types of pesticides using state of the art equipment operated by the California Department of Food and Agriculture.

    Highlights from the 2016 report include:

    • 39 percent of all produce samples had no detectable residues at all,
    • 57 percent had residues detected within the legal level.
    • 4 percent of the samples had pesticide residues in excess of the established tolerance or had illegal traces of pesticides that were not approved for that commodity.

    Produce that most frequently tested positive for illegal pesticide residues in 2016 include Snow Peas from Guatemala, Longan from Vietnam, Ginger and Lichti nuts fruit from China; Cactus pads from Mexico; and Bok Choy from the United States.

    If illegal residues are found DPR immediately removes the illegal produce to prevent it from reaching consumers and the department also attempts to trace it to its source. DPR then verifies that the produce is either destroyed or returned to its source.

    Businesses that violate California pesticide residue laws face loss of their product and fines. For example, in September 2016, DPR imposed a $10,000 fine against a California grower after an illegal pesticide was detected on his grapes in the marketplace and on the crop in his 43-acre vineyard.

    The new regulation:

    • The survey included 3585 produce samples representing 161 different fruits and vegetables
    • Each sample is approximately 2 pounds of produce
    • Produce sampled originated from 27 countries
    • Californian grown produce accounted of 24% of all samples tested
    • 96% of all samples had either no detected pesticide residues levels or levels at or below U.S. EPA tolerance levels

  • Almond and Walnut Pest Management Guidelines Revised Just in Time for the Holidays

    Davis, Calif., (December 27, 2017) – ‘Tis the season for baking lots of tasty treats. Breads, cookies, cakes, and candy are just a few that come to mind. What makes many of these treats so tasty is the addition of almonds or walnuts to the list of ingredients.

    California is the top almond producer in the world, accounting for about 80% of all almonds grown. (Photo: Jack Kelly Clark)

    In California, we are lucky to be at the center of almond and walnut production. According to the California Department of Food and Agriculture’s (CDFA’s) latest Agricultural Statistics Review, more than 99 percent of the almonds and walnuts produced in the United States are grown in California.

    Almond and walnut growers work tirelessly to supply enough nuts to not only satisfy domestic demand, but also for export. Worldwide, almonds rank as the largest specialty crop export. California is the top almond producer in the world, accounting for about 80 percent of all almonds grown. For walnuts, California ranks as the second largest producer in the world. To keep up with this demand, almond and walnut growers must be constantly aware of pests, diseases, and abiotic problems that can affect the tree and growing nuts.

    The University of California Statewide Integrated Pest Management Program (UC IPM) has recently published revised Pest Management Guidelines for almonds and walnuts, helping growers prevent and manage pest problems with the most up-to-date information.

    Bacterial spot on almond, a new disease of almond in California. (Photo: Brent A. Holtz)

    Revisions in the Almond Pest Management Guidelines include:

    • A new section on bacterial spot, a new disease of almond in California found in the Sacramento and northern San Joaquin valleys
    • A renamed section on fruit russeting, revised from the old powdery mildew section
    • Significant revisions made to the management section of navel orangeworm, one of the major pests attacking California almonds
    • Improvements on how to do dormant spur sampling section with easier-to-understand information on monitoring and thresholds
    • Revisions in the Walnut Pest Management Guidelines include:
    • Updated information on the association between walnut twig beetle and thousand cankers disease
    • New sections for Botryosphaeria and Phomopsis cankers, branch wilt, and paradox canker
    • Significant changes to the walnut husk fly management section
    Male (left) and female walnut twig beetles. (Photo: Larry L. Strand)

    Both the almond and walnut revised Pest Management Guidelines also include updated information on fungicide efficacy, weed management, and vertebrate management.

    Authored by University of California specialists and advisors, the Pest Management Guidelines are UC’s official guidelines for monitoring and managing pests in California crops. For more information on pest management in these or other crops, visit the UC IPM website.

  • Medfly Quarantine In Portion Of San Mateo County

    Sacramento, Calif., (December 21, 2017) – A portion of San Mateo County has been placed under quarantine for the Mediterranean fruit fly (Medfly) following the detection of two Medflies within the City of Half Moon Bay.  CDFA is working collaboratively with the USDA and the San Mateo County Agricultural Commissioner’s office on this project.

    The quarantine area measures 56 square miles, bordered on the north by San Vicente Creek; on the south by Lobitos Creek Road; on the west by the Pacific Ocean; and on the east by Lower Crystal Springs Reservoir. A link to the quarantine map may be found here: www.cdfa.ca.gov/plant/medfly/regulation.html.

    Sterile male Medflies will be released in the area as part of the eradication effort.  The release rate will be 500,000 males per square mile per week in a 12 square mile area around the infestation.  In addition, properties within 200 meters of detection sites are being treated with an organic formulation of Spinosad, which originates from naturally-occurring bacteria.

    Sterile male Medflies are provided by the joint CDFA/USDA sterile insect rearing facility in Los Alamitos, which prepares sterile files for release every day over the Los Angeles basin.  The sterile release program has a proven track record of success in California. Sterile male flies mate with fertile female flies in the natural environment but produce no offspring.  The Medfly population decreases as the wild flies reach the end of their natural life span with no offspring to replace them, ultimately resulting in the eradication of the pest.

    The quarantine will affect any growers, wholesalers, and retailers of susceptible fruit in the area as well as nurseries that grow and sell Medfly host plants. The quarantine will also affect local residents – home gardeners are urged to consume homegrown produce on site and not move it from their property.  These actions protect against the artificial spread of the infestation.

    The Medfly can infest more than 250 types of fruits and vegetables, causing severe impacts on California agricultural exports and backyard gardens alike.  Residents who believe their fruits and vegetables are infested with fruit fly larvae are encouraged to call the state’s toll-free Pest Hotline at 1-800-491-1899.

    While fruit flies and other invasive species that threaten California’s crops and natural environment are sometimes detected in agricultural areas, the vast majority are found in urban and suburban communities.  The most common pathway for these invasive species to enter our state is by “hitchhiking” in fruits and vegetables brought back illegally by travelers as they return from infested regions of the world.  To help protect California’s agriculture and natural resources, CDFA urges travelers to follow the Don’t Pack a Pest program guidelines (www.dontpackapest.com).

     

  • Barn Owl Helps Clean Up Rodents Naturally

    Woodland, Calif., (November 16, 2017) – The screech of a barn owl at night may be startling or annoying to some. But others may find their harsh calls satisfying, knowing that barn owls are out, feeding on pesky rodents.

    Barn owl adult, photo by G. Rohman, grohman@gmail.com

    They’re fierce hunters with a voracious appetite for mice, voles, gophers, and rats. A family of five barn owls, including two adults and three young will feed on about 1,000 rodents during a season. When they nest twice in a year, that number doubles and you wind up with some good help on rodent control that’s safe and free.

    So, the next time you hear that eerie, rasping sound at night, don’t panic. Instead, think about all the good the owls are doing. Even better, invite a family of barn owls to your property by building a nest box for them and creating a home.

    Identifying barn owls. If you’re lucky to spot one in an old barn where they’re often found (hence their name), they have iconic white heart-shaped faces, white chests, and tan-colored backs with spots. Barn owls are nocturnal and can be recognized by their drawn-out rasping screech. Unlike other owls, they don’t hoot. They often shriek when they leave their roost to hunt and make hissing and snapping sounds when startled.

    Barn owls have excellent vision and hearing for finding prey in the dark and capturing it with their sharp talons and beaks. They’re quiet hunters, flying close to their prey without being heard, due to specialized feathers, making them incredibly good predators. Barn owls are found world-wide and occupy a wide range of habitats, including natural, agricultural, and urban areas, but prefer to hunt in more open areas as opposed to forests. They readily hunt rodent pests in grape vineyards, alfalfa fields, and along levees, making them valuable allies for farmers.

    Barn owl with a gopher on a nest box. (Photo: G. Rohman)

    How do you attract barn owls? Barn owls are cavity nesters, including cliffs, trees, and buildings such as barns, so they will readily use nest boxes. Plans for how to build nest boxes can be found in the UC Agriculture and Natural Resources (UC ANR) booklet, Songbird, bat, and owl boxes. This handy guide also shows how to attract insectivorous birds and bats to help control insect pests naturally.  Barn owl boxes and plans can be found online or through local sources, such as G. Rohman (photographer). Barn owls begin nesting in February, so now is the time to put up a house before males and females select nest sites. Boxes should be mounted 10 feet off the ground on metal poles to prevent mammal predators from accessing the boxes and feeding on eggs or chicks.

    Barn owl house on a pole. (Photo: G. Rohman)

    Paint the boxes white to keep them cooler and help prevent weathering and face them northeast. Add some timothy hay for bedding (often sold in small bags in stores for rabbit feed). Wooden nest boxes are generally preferred over plastic ones. Fifty gallon drums can also be used; just remove the top, retaining a lip so the chicks don’t fall out, add some hay, and hoist it up on a rafter in a barn and secure it well with a chain. Avoid disturbing nest boxes during the breeding season (February through August), as barn owls will often abandon nests if disturbed while nesting.

    Who moves into the nest box? A family of barn owls. Females generally lay four to seven eggs from February to April, which hatch in about 30 days. While they incubate the eggs, the males bring food to the nest. The baby owls fledge in about 10 weeks, but stay around the nest until fall, when they wander off, usually within 30 miles of where they were born. Sometimes a second clutch of eggs is laid in May. Barn owls do not migrate, so tend to stay in an area year-round and will reoccupy a nest box the following year. They generally forage about one to three miles from their roosts. They are only mildly territorial in that they will defend their nests if you get too close. This means that you can put up several nest boxes in an area and expect occupancy from several families. Barn owls generally only live for about two years. Great horned owls are the fiercest predator of adult barn owls (and collisions with cars).

    Barn owl bringing prey back to the nest box. (Photo: G. Rohman)

    What are they eating? The favored prey of barn owls is rodents, including voles and gophers. Like other owls, they often swallow their prey whole and then undigested bones and fur are coughed up (regurgitated) as owl pellets. These pellets can be dissected and prey readily identified by the skeletons left behind. Farmers appreciate owls and other raptors because they feed on rodents that can damage their crops and irrigation systems (Wildlife Survey).

    Barn owl pellets. (Photo: Chuck Ingels)

    UC ANR researchers, including Roger Baldwin, UC Cooperative Extension vertebrate pest control specialist, are currently evaluating the economic impact of barn owls for rodent control in agricultural lands. It is important to note that rodents reproduce rapidly so barn owls cannot always keep up with rodent outbreaks and other methods of control might be needed to prevent crop damage (Rodent Control). But, every rodent a barn owl takes is one less we have to deal with!

    How about maintenance? Barn owl boxes need to be cared for and cleaned once a year during fall or winter (October to December) as the pellets can quickly fill up a nest box. Doors for accessing the inside of the boxes need to be secured, hinges lubricated, and mounting structures checked during annual inspections. Avoid breathing unhealthy dust when cleaning the house and always make sure no one is home. Although this takes time, the pellets cleaned out might have added value. A Yolo County farmer mentioned he has a buyer for his pellets, which are used for science projects where students dissect them to learn about skeletons and barn owl diets. He read his recent owl pellet invoice noting, “The pellets are graded from small at 10 cents each to premium at 20 cents each and I sold over 100. Barn owls are great!”

  • California Adopts Rules on Agricultural Pesticide Use Near Schools and Day-Care Centers

    Sacramento, Calif., (November 9, 2017) – The California Department of Pesticide Regulation (DPR) has adopted new rules to further protect young students from pesticide exposure. The rules, which take effect on January 1, 2018, regulate the use of agricultural pesticides near schools and licensed child day-care facilities.

    “These rules will help to further protect the health of children, teachers and school staff from unintended pesticide exposure,” said Brian Leahy, DPR director. “They build on our existing strict regulations and give an additional layer of protection that is now consistent across the state.”

    The new regulation was adopted following an extensive process to gather public and stakeholder input during the past two years. DPR conducted three formal hearings and 15 public workshops in five locations around the state to gather input and reviewed more than 19,000 public comments.

    The new regulation:

    • Prohibits many pesticide applications within a quarter mile of public K-12 schools and licensed child day-care facilities during school hours, Monday through Friday between 6 a.m. and 6 p.m. This includes all applications by aircraft, sprinklers, air-blast sprayers, and all fumigant applications. In addition, most dust and powder pesticide applications, such as sulfur, will also be prohibited during this time.
    • Requires California growers to provide annual notification to public K-12 schools and licensed day-care facilities, as well as county agricultural commissioners, of the pesticides expected to be used within a quarter mile of these schools and facilities in the upcoming year.

    Although California has strict regulations governing the use of pesticides, population growth has created a growing number of situations where schools and day-care facilities are located near or directly adjacent to working farms, increasing the potential for unintended exposures to pesticides.

    Many California counties have adopted local rules related to pesticide applications near schools and day-care centers, but until now, the state did not have a consistent, statewide standard. The regulation is expected to affect about 4,100 public K-12 schools and licensed child day-care facilities and approximately 2,500 growers in California.

    In addition to tightening restrictions, the regulation is designed to encourage greater communication between growers and schools or licensed daycare facilities. By providing more information on nearby pesticide applications and increasing communication, the new rules are expected to help schools and day-care centers in responding to potential incidents and inquiries from parents.

    The regulation also allows a school, a grower and the county agricultural commissioner to devise alternative application restrictions that provide an equal or greater level of protection to those provided by the regulation. The new regulation and other related documents can be found at http://www.cdpr.ca.gov/docs/legbills/rulepkgs/16-004/16-004.htm