California Ag Network

Tag: UC Cooperative Extension

  • Placer County Team Demonstrates Value of Participating in 4-H

    4-H is America’s largest youth development organization. Its hands-on approach has been proven to foster life skills like confidence and independence as members learn by doing.

    For proof, look no further than the livestock judging team from Placer County, just north of Sacramento. The Ophir 4-H Club team started from scratch just five years ago and won the 4-H state championship in both 2023 and 2024. Most of the members were too young in 2023 to compete in the national competitions, but the 2024 team passed the age test and headed to the National Western Roundup in Denver, Colo., this January to take on teams from all over the country.

    “We started (the team) when we realized that not many 4-H kids were doing judging in California,” said team coach Liza Stefani, who along with her husband, Jonathan, has been a 4-H volunteer for more than 20 years. “FFA is heavily involved in competitions, but you have to go to a school with an FFA program and several of our kids don’t. 4-H allows kids to participate who otherwise wouldn’t have access to do so.”

    Junior Moriah Marshall is an original team member. She recalls that the team came together quickly.

    “Liza called us up a week before a contest and asked if I wanted to do it with her son, Joey. I said sure, we watched two videos and then did the contest. We didn’t do that bad – we did better than some of the older kids. But looking at my scores then compared to 2024 is crazy. None of us knew what reasons were,” Moriah said.

    “Now I can look at a class of livestock and know what I see and come up with a set of reasons. It’s more fun now that we actually know something.”

    Livestock judging consists of two primary components – placing (or ranking) a group of animals and orally justifying your decision, or as it’s commonly known, giving reasons.

    Joey Stefani said he first started judging because his parents were launching the program but found he really liked it.

    “When I found out that I could raise animals and do speaking contests, I stuck with it,” he said. “I wanted to get better at picking out animals to raise, and I also like the competitive aspect of the public speaking and the leadership involved.”

    Ella Miller, a high school senior, joined the team after another girl transitioned out of 4-H. Now in her eighth year in 4-H, she was interested in judging to raise her market lambs better and select the best animal to show. It apparently paid off as her market lamb placed third overall at the Gold Country Fair last year.

    Miller said teams are typically split up into groups and have 10-15 minutes to judge each pen of four animals, pigs or cattle, for market or breeding. Groups normally judge between seven and 10 pens, and after each judge fills out an evaluation, they take notes for the oral presentations.

    “For 30 minutes, you give your reasons and explain to your judge – who typically is someone who bought one of the animals – why you placed each class the way you did. You have to memorize your reasons and can’t look at notes,” she said.

    The team’s fourth member is Gabriel Kitchen.

    Tiffany Lionudakis, Senior Relationship Manager with American AgCredit, said the Placer County team reflects the important values youth learn in 4-H.

    “They develop public speaking skills and leadership skills that are invaluable in life,” Lionudakis said. “In addition to judging, some members have the opportunity to raise and market livestock. Raising project animals allows them to learn how to manage time and money at a young age – with some students completing their first income and expense statement as early as 9 years old. Those financial skills are critical, and with skills like these, it’s no wonder 4-H alumni are true leaders.”

    Moriah, Elsa and Joey also plan on pursuing careers in ag-related fields. Moriah wants to become a cloven-hoof animal veterinarian, Ella is considering being a vet or studying embryology and Joey is thinking about ag mechanics – or even becoming a professional livestock judge.

    Kevin Ralph, AgWest Farm Credit’s California President, said it’s important that young people pursue careers in California agriculture.

    “Farm Credit proudly supports organizations like 4-H that help shape the next generation of leaders as they develop industry expertise, leadership competencies and advocacy skills,” Ralph said. “It’s encouraging that outstanding youth like the members of the Placer County team will help keep California agriculture a world leader for decades to come.”

    Farm Credit associations AgWest Farm Credit, American AgCredit, CoBank, Colusa-Glenn Farm Credit and Fresno Madera Farm Credit sponsor California 4-H. The organizations are part of the nationwide Farm Credit System – the largest provider of credit to U.S. agriculture.

    Liza Stefani said the public speaking part of the competition is crucial and contestants must have the ability to think on their feet, adapt and change. She noted that one junior team member at a competition completely forgot what he was going to say.

    “He said he just made it up as he went and actually scored one of the highest scores on the team for that section because he was as confident as he could be. You just fake it ‘till you make it sometimes,” she said.

    The team members were glad to have had the experience of competing in one of 4-H’s three national competitions. Liza Stefani said it was a great learning experience – which was what everyone had expected from the event in January – one of three national 4-H competions.

    “The kids did great at nationals. They came in 25th, which, of course, is not what they would’ve hoped for, but they learned a lot. It was a very steep competition,” she said. And because of the successes the team has had, last year they added a junior team that shows great progress.

    While the team loves raising animals, it’s never easy to say goodbye to one they have raised and trained for several years. But Joey sees a practical side as well.

    “It is really hard to sell them. Especially the first few days, it’s really difficult to know they are gone – you miss working with them. But after a few weeks, when you get your money for selling them, that’s when you start to feel better. And knowing you’re feeding families is good as well,” he said.

    About Farm Credit: 

    AgWest Farm Credit, American AgCredit, CoBank, Colusa-Glenn Farm Credit and Fresno Madera Farm Credit are cooperatively owned lending institutions providing agriculture and rural communities with a dependable source of credit. For more than 100 years, the Farm Credit System has specialized in financing farmers, ranchers, farmer-owned cooperatives, rural utilities and agribusinesses. Farm Credit offers a broad range of loan products and financial services, including long-term real estate loans, operating lines of credit, equipment and facility loans, cash management and appraisal and leasing services…everything a “growing” business needs. For more information, visit www.farmcreditalliance.com

    About the California 4-H Program:

    The University of California 4-H Youth Development Program promotes hands-on, experiential learning for all youth ages 5-19. We provide meaningful opportunities for youth and adults to work together to create sustainable community change in the areas of Civic Engagement, Leadership, Healthy Living and STEM (Science, Technology, Engineering and Math). Our 4-H programs are delivered locally through the county University of California Cooperative Extension offices, where youth participate in 4-H through clubs, schools, military clubs, camps and more. Each year, approximately 100,000 youth and over 10,000 volunteers participate in the California 4-H Youth Development Program.

  • UCCE Viticulture Advisor and Exceptional Plant Pathologist Passes

    George M. Leavitt, Jr., UC Cooperative Extension viticulture advisor emeritus for Madera County, passed away in Paso Robles on April 21, 2025. He was 79.

    Leavitt served as the UCCE viticulture farm advisor for Madera County from 1975 until his retirement in 2006. During his 34-year UCCE career, he was recognized as an exceptional plant pathologist specializing in grapevine trunk diseases like Botryosphaeria, Eutypa and Phomopsis dieback.

    Prior to becoming a UCCE viticulture farm advisor, Leavitt worked as a staff research associate for the distinguished UCCE viticulture specialist Fred Jensen. While finishing up his master’s degree at Brigham Young University, Leavitt found it was the perfect job because Jensen led a busy lab focused on evaluating plant growth regulators and cultural operations for table grape production.

    Leavitt would go on to use the trial methodology in his own large field trials that became popular with Madera County growers. After Jensen’s retirement, Leavitt would check in with him regularly to discuss industry issues over lunch, which often included Larry Bettiga, UCCE viticulture farm advisor in Monterey County and former Jensen staff research associate.

    “George arranged a lunch meeting every year and we continued to meet annually after Fred’s passing for a Jensen memorial luncheon,” Bettiga said.

    In the early 1980s, Leavitt began work on his Ph.D. He took a sabbatical to complete his course work at UC Riverside and returned to Madera to continue and finish his field work, which was focused on grapevine canker diseases, under the tutelage of Donald E. Munnecke, Ph.D., at UC Riverside, whose philosophy was that fieldwork made the researcher. Leavitt had been working with growers to identify the cause of dying cordons and noticed the symptoms varied greatly and didn’t fit the traditional tattered leaf symptoms that E. lata is known to cause.

    From left, Stephen Vasquez, Leavitt, Fred Jensen and Larry Bettiga. Leavitt showed his appreciation for his mentor, Fred Jensen, with an annual lunch that often lasted 3-4 hours. They would discuss the grape industry and dates for their next ski trip.

    Leavitt took Munnecke’s adage to heart and collected numerous samples from California, Arizona and northern Mexico vineyards, documenting symptoms, collecting samples, spending hours in the laboratory, plating them on auger plates and looking through a microscope to identify the different fungi. His hard work paid dividends, because he determined that Botryosphaeria theobromae was the other fungus infecting grapevines, causing “Bot canker.”

    After retirement, Leavitt mentored early-career plant pathologists working on canker diseases who brought a different set of skills and approach to working on grapevine cankers, which was primarily focused on lab research. However, he would gently remind them of the importance of collecting their own field samples.

    Leavitt enjoyed field days and looked for opportunities to train the next generation of plant pathologists.

    Growers regarded Leavitt as a consummate professional and educator. “You could always count on learning something from him,” said Kip Green, a former vineyard manager and current Pest Control Adviser and Certified Crop Adviser. “George was generous with his time and always made sure you had the information to make the right decision in the vineyard.”

    Leavitt held monthly grower meetings at the Howard School building in Madera, which was turned into a restaurant by local caterer, Dino Petrucci, who renamed it “Old School House.” Petrucci, a grape grower himself, made sure his grower colleagues didn’t go hungry, serving up tri-tip sandwiches, potatoes, beans, salad and dessert for $10! Growers would meet for lunch and receive one hour of continuing education credit to maintain their Private Applicator License.

    Leavitt would often present a topic, but would also have his UC ANR colleagues give talks on relevant grape issues, like insect pests or weeds. A grower once said “You never leave George’s meeting hungry or bored. The discussion is always lively.”

    Leavitt’s powdery mildew field days started with him standing in the truck bed and reviewing the fungicide treatments with growers and reporters taking notes.

    In addition to working on grapevine trunk diseases, Leavitt also conducted powdery mildew fungicide trials at a local grower’s vineyard. The trials were extensive, often having 30-plus treatments that included multiple combinations of registered and experimental fungicides. Grape growers from Bakersfield to Modesto would attend the field day to learn about the latest products.

    Stephen Vasquez, a former UCCE viticulture advisor who served in Fresno County for 14 years, attended the field days and described them as a “who’s who of the grape industry.” “Everyone wanted the information so they could prepare for the next season,” Vasquez said.

    Tome Martin-Duvall, a former UC technician who worked for Leavitt and oversaw the powdery mildew trials, mentioned that 50 to 100 growers would attend the field days.

    “Bad mildew the previous season would result in increased attendance the next season,” said Martin-Duvall. “You could often meet up with other UCCE farm advisors, too, because they wanted to share the trial data with their growers.”

    After retiring in 2006, Leavitt remained involved in the grape industry and research. He supported UC colleagues by presenting at their local meetings on grapevine disease management. He also worked with international colleagues on separating grapevine fungal pathogens using DNA technology.

    “He never lost interest in viticulture research,” said Vasquez. “He always wanted the newest information so he could share it with his grower friends in the San Joaquin Valley.”

    George Leavitt was a grape plant pathologist and was always evaluating new technologies to improve disease management for growers.

    Leavitt made significant contributions to California viticulture and was recognized by the University of California, the California Association of Pest Control Advisers and the San Joaquin Valley Winegrowers Association for his research and extension program.

    Leavitt is survived by his wife Annette, seven children, 36 grandchildren and six great-grandchildren.

    Funeral services for Leavitt were held on Saturday, May 3, 2025 at The Church of Jesus Christ of Latter-Day Saints, 2600 Ramona Road, Atascadero, California. Those wishing to honor Leavitt’s life can make donations to Court Appointed Special Advocates San Luis Obispo at slocasa.org. — Article by Stephen Vasquez and Larry Bettiga

  • UCCE Kern County Potato Variety Trial Field Day

    The Annual UC Cooperative Extension and California Potato Research Advisory Board Variety Trial Field Day is an opportunity to see tubers of potentially new varieties, how they performed this year, and how they performed compared to standard varieties. Entries include varieties from numerous USDA, state, and private breeding programs. This year’s entries include Russets, chippers, reds, yellows, and specialty types. Tubers will be shown as how they look straight from the field after being washed. This is an opportunity to express your evaluations and recommendations about these varieties to University researchers, breeders, seed growers, and fellow growers.

    The Field Day will take place on Wednesday, June 11, 2025, 10a.m. to 12:30p.m.

    LOCATION! The Potato Field Day will be held in the shade near the bank of the Kern River at HART PARK. It will be located on the east end of the park in Section 2, just off Alfred Harrell Highway. Please see map on back for directions to Hart Park. Snacks and refreshments will be available.

    Potato Grower Meeting: You should be receiving a notice from the CPRAB for the annual potato grower’s dinner and informal meeting to be held the evening of the field day.

    For further information contact:

    Jaspreet Sidhu, Kern County Cooperative Extension, 661-304-8870

    Nathan Sano, California Potato Research Advisory Board, 559-591-0436

  • South Coast REC Studies Pesto Profitability for Small-Scale Basil Growers

    If you visited the greenhouse at the University of California South Coast Research and Extension Center in early fall, you would have smelled a sweet aroma with notes of lemon, pepper and licorice.

    In one of the conservatories, a team of UC Cooperative Extension advisors and staff grew seven varieties of basil and by the end of October, the plants stretched nearly two feet tall with leaves large enough to warrant a closer look. The wonderful smell would soon become delightful tastes, as the team planned to turn the basil into pesto.

    L to R: Gerry Spinelli, Chris Shogren, UCCE Environmental Horticulture Advisor, Lindsey Pedroncelli and Natalie Levy, UCCE Soil Health and Organics Material Management Advisor, pose with a batch of fresh pesto.

    “The rationale was to provide a high-value crop and a value-added solution for urban horticulture, transforming a highly perishable product into something that can be conserved,” said Gerardo “Gerry” Spinelli, UC Cooperative Extension production horticulture advisor for San Diego County, who initiated the passion project.

    After noticing a sign at South Coast REC asking consumers to use produce grown onsite in their everyday cooking, Spinelli felt inspired. The sign also requested photos of homemade dishes be sent to South Coast REC’s interim director, Lindsey Pedroncelli, to generate content for the REC’s Instagram account.

    Envisioning a “bigger picture” for this effort, Spinelli turned to Pedroncelli for support. The two agreed that the basil project demonstrates a viable pathway for urban growers who have limited space, and positions South Coast REC as an ideal partner for such endeavors. Uniquely located in urban Irvine, South Coast REC has nearly 200 acres of land reserved for agricultural research and is one of nine RECs housed under UC Agriculture and Natural Resources.

    “Urban growers are constantly looking for new ways to grow food and market their products. Growing plants using the Kratky hydroponic system is a low-input method that is simple to establish and easy to maintain,” said Pedroncelli.

    Aside from its research purposes, the project was the perfect opportunity to engage other advisors and staff at South Coast REC. The extra hands and taste buds that helped with this effort would later be known as the South Coast REC Pesto Task Force.

    Growing in hydroponics

    Given Spinelli and Pedroncelli’s Italian ancestry, it was no question that the basil would be used to make pesto – a traditional sauce originating from Genoa, Italy that’s commonly consumed on pasta. In just about two months, the following basil varieties flourished in a hydroponic system: cinnamon, Mrs. Burns’ Lemon, Kapoor Tulsi, Thai Towers, Amethyst Improved, Red Rubin and the traditional Genovese. With these varieties, Spinelli and Pedroncelli were also interested in testing how taste and color affect the pesto.

    Since learning about the Kratky method, a passive hydroponic technique developed by Bernard Kratky at the University of Hawai’i, Spinelli has championed it as an easy and affordable way to grow food. He has produced several videos in English and Spanish about the technique on his YouTube Channel and created a fact sheet that can be downloaded from his website.

    Some of its advantages are the low initial capital investment, excellent water and nitrogen use efficiency, short cycle of production and the fact that it is modular and easy to set up, move and store – a major advantage for growers who only have access to space for a limited time and investments on immobile structures are not justifiable.

    For the setup, eight 2’-by-3’ tubs were used, and each was filled with 20 gallons of water before adding a fertilizer mix that contains one ounce of calcium nitrate, one ounce of magnesium sulfate or Epson salt and 0.6 ounces of lettuce formula. With the additional steps of seeding, drilling holes into the Styrofoam, and placing the net cups with seedlings into each hole, Spinelli estimated about 30 minutes of setup for each tub.

    A few of the basil varieties before they were harvested to make pesto.

    Estimating potential profit for urban growers

    Although prices per quantity vary, he also estimated about $25 for the 20-gallon tub, a panel of Styrofoam and net baskets, which can all be reused. In addition, the fertilizer and propagation materials, including seeds and pellets, will cost roughly $68. When breaking these materials down according to the number of growing cycles, about one to two months each, the cost amounts to approximately $5 per tub for 25 cycles.

    Using basil sold at Trader Joe’s for reference, Spinelli estimated that each ounce of basil grown is worth about 70 cents. The “million-dollar question,” as Spinelli puts it, is how much profit one can earn from this endeavor. Because the Amethyst Improved and Red Rubin varieties had the lowest yields of 12 and 18 ounces, they were combined to make 40 ounces of pesto. In contrast, Genovese had the highest yield of 51 ounces of basil – which produced 64 ounces of pesto.

    Using a ratio of 0.7 to 0.9 ounces of basil for every liquid ounce of pesto, and calculating projected value based on Trader Joe’s pricing, the Amethyst Improved and Red Rubin combined pesto had a projected value of $21, whereas Genovese had a projected value of $36. Without being combined with any other variety, however, the smallest projected value was the Kapoor Tulsi variety which had a yield of 22.5 ounces, making 28 ounces of pesto and resulting in a $16 projected value.

    There are a few costs that Spinelli and Pedroncelli could not account for, such as hypothetical transportation to the market for sale, and the various prices of ingredients used to make pesto – almonds and walnuts, for instance, could be used as a cheaper alternative to the traditional pine nuts.

    “With a traditional recipe you spend $5 for the basil and $25 for the other ingredients to produce eight 8-ounce jars of pesto. If you can sell each jar for $10 at the farmers market, there are $50 for profit – maybe more if you can sell one jar for $15, or you can save with non-traditional ingredients,” Spinelli explained.

    An additional advantage, which may come with additional expenses, is that pesto can be conserved. The business model could be that the grower sells basil at the farmers market and transforms the unsold product into pesto before it goes bad.

    “Getting involved in agriculture can be intimidating and costly, so researching and showcasing inexpensive methods that can easily be scaled to fit your needs is incredibly helpful for both new and seasoned growers,” Pedroncelli said.

    South Coast REC staff offer taste buds at ‘pesto party’

    Following their harvests in October, Spinelli and Pedroncelli hosted two “pesto parties” for staff at South Coast REC. Although traditional pesto is made with Genovese basil, pine nuts, garlic, Pecorino cheese and olive oil, Spinelli and Pedroncelli experimented with different cheeses and nuts across the seven varieties of basil. Staff offered their taste buds and critical review of each pesto, advising the two chefs to add more or less of a particular ingredient.

    Eager to share their progress and vision with UC ANR’s senior leadership, Spinelli and Pedroncelli carefully preserved and packaged eight jars of homemade pesto and had it specially delivered to Vice President Glenda Humiston.

    “This is a creative way to demonstrate innovation and a fantastic opportunity to support our urban communities. It’s not just practical, but economically feasible,” said Humiston, who was pleasantly surprised by the pesto delivery. “Plus, I love pesto!” she added.

    What started out as a passion project quickly turned into an opportunity to show how a resource hub like South Coast REC can empower its urban clientele both educationally and economically. It was also the perfect opportunity to engage South Coast REC staff in an activity outside of their day-to-day responsibilities, making for excellent photo ops and social media posts. — By Saoimanu Sope, UCANR

    Darren Haver (left), REC System Director, and Saoimanu Sope (right), Digital Communications Specialist, present the gift of pesto to Vice President Glenda Humiston (center) from the South Coast REC Pesto Task Force.

    UC Agriculture and Natural Resources brings UC information and practices to all 58 California counties. Through research and Cooperative Extension in agriculture, natural resources, nutrition, economic and youth development, our mission is to improve the lives of all Californians. Learn more at ucanr.edu.

  • Watermelon Growers Face Challenges When Expanding Their Season

    Watermelon is a favorite summertime treat for consumers. Naturally anticipating those summer picnics and BBQs, consumers may want to enjoy this sweet treat earlier or even later in the year, outside of California’s traditional harvest window. Determined to meet consumer demand with an innovative spirit, California growers are planting watermelons earlier than ever before and expanding their seasons late into the fall as well. This does not come without consequence though, and growers faced some particular challenges during their extended 2024 season that they won’t soon forget. Watch this brief interview as Zheng Wang, UCCE Vegetable Crop Advisor — specializing in Central Valley melon crops, discusses these challenges with Matthew Malcolm on California Ag Network. Read more in California Fruit & Vegetable Magazine.

  • Former Kern County Viticulture Farm Advisor Passes

    Donald A. Luvisi, UC Cooperative Extension viticulture advisor emeritus of Kern County, passed away in Bakersfield on July 10 at the age of 87.

    Luvisi served as the viticulture farm advisor for Kern County from 1960 until his retirement 39 years later in 1999. He was widely recognized as a pioneer of the modern-day California table grape industry and his research influenced a significant expansion in the production of varieties such as ‘Flame Seedless,’ ‘Redglobe’ and ‘Crimson Seedless,’ along with improvements in fruit quality associated with his work with gibberellin, ethephon and girdling.

    “He gave table grape growers the knowledge they needed to maximize packable yields by investigating and extending the nuanced production practices specific for each variety,” said Rhonda J. Smith, UCCE viticulture farm advisor emeritus.

    Luvisi was widely regarded as an expert in postharvest handling of table grapes due to the impacts of his work on sulfur dioxide (SO2) fumigation. SO2 is used to inhibit the growth of fungi that can break down fruit in storage. In 1987, SO2 was removed from the ‘Generally Regarded As Safe’ (GRAS) listing by the U.S. Food and Drug Administration (FDA), and as a result, residue data and new application patterns had to be developed to prevent grapes from decaying in storage. Luvisi responded through his participation in more than 20 experiments annually that led to the acceptance of the “Total Utilization Fumigation” method and conversion of much of the industry to it from traditional fumigation. The restoration of newly approved postharvest SO2 fumigation methods was estimated to prevent 40%-50% losses in table grape production that at the time was valued at $200 million to $250 million.

    The last decade of Luvisi’s career was focused on the evaluation of rootstocks for table grape production. These rootstocks were developed as a response to growers reporting replant problems in second- and third-generation vineyards due to the buildup of plant-parasitic nematodes in the soil. He conducted more than a dozen decade-long trials evaluating the performance of common table grape varieties on these rootstocks that led to guidelines for their use by local growers. The use of soil-borne pest resistant rootstocks has become an industry standard practice within the California table grape industry.

    “Don was an internationally respected viticulturist, with particularly broad knowledge of table grape and wine production,” said Matthew Fidelibus,UCCE viticulture specialist. “He was also a generous and beloved colleague.”

    Don Luvisi was not only an internationally respected viticulturist, “he was also a generous and beloved colleague,” said Matt Fidelibus, shown on left with Luvisi.

    After retiring in 1999, Luvisi split his time between Bakersfield and Calistoga, where he managed a family vineyard. When in Bakersfield, he was generous with his time as a mentor to three subsequent UCCE Kern County viticulture advisors, and frequently met with his friends within the table grape industry.

    In the early 2000s, he was highly influential in the development of the ‘General Beale Pilot Project’ that developed and tested area-wide management programs to control the glassy-winged sharpshooter, a vector of the potentially devastating Pierce’s disease of grapevines. His knowledge of the grape industry, combined with the personal relationships he had developed over a lifetime, proved invaluable in establishing this highly successful project that remains effective today.

    Following his passing, former UCCE viticulture advisor Jennifer Hashim-Maguire said, “I’m forever grateful for having Don as a mentor and friend. His early tutelage at Cooperative Extension sowed the seeds of a career in table grape production that now spans decades and several countries.

    “Luvisi’s passion for the advancement of the grape industry was contagious and unsurpassed. As a (wine) grower himself, he understood firsthand the challenges of farming and was eager and generous to share technical information and solutions with growers all over the world.

    “Don’s legacy is measured not just in past research conducted and the growers he helped throughout his life, but in his kindness and the numerous relationships he cultivated in the industry from California to Australia, Chile to Greece and numerous places in-between,”Hashim-Maguire said. “The global table grape industry is an interconnected extended family and I know that I’m only one of many who will miss him deeply.”

    Luvisi was an “exceptional mentor,” said Stephen Vasquez. From left, Allison Ferry-Albee, Ashraf El-kereamy, Luvisi and Vasquez.

    Stephen Vasquez, a former UCCE viticulture advisor who served in Fresno County for 14 years, described Luvisi as an “exceptional mentor” who was always generous with his time and freely shared his knowledge, leaving a lasting impression on Vasquez who was a young viticulture plant pathologist in 1999.

    “As a UC Davis plant pathology grad student working on grape diseases, Don would drive me around Kern County and show me areas with high incidences of grape diseases. We’d look at powdery mildew, measles, bunch and sour rots, etc. and talk about why they were problems in the vineyards we visited. The next time I was in town, Don would drive me around new vineyards and test my knowledge. Often, I would be stumped, and he’d explain the subtleties of the diseases. This scenario lasted for two summers, and I was grateful for the experience.

    After completing his master’s degree, Vasquez applied for a viticulture farm advisor position in Fresno County. Luvisi was on the hiring committee along with several other viticulture farm advisors. “I was prepared to be grilled. Instead, he questioned me on grapevine disease scenarios with slight twists, which I had been trained to solve the past two summers. Don’s plan wasn’t to prepare me to be a farm advisor, he saw an opportunity to share his knowledge with someone who was interested in learning,” said Vasquez, who is now executive director of the Administrative Committee for Pistachios and looks for opportunities to share his knowledge with early career scientists.

    Funeral services for Luvisi were held at St. Francis Church in Bakersfield on July 30 and burial on Aug. 1 at the Holy Cross Catholic Cemetery in St. Helena.

    Those wishing to honor Luvisi’s life through contributions are encouraged to donate to the Don and Mickie Luvisi Agriculture Scholarship at Calistoga Junior/Senior High School. Donations to the scholarship fund can be made online at this link: https://www.convergepay.com/hosted-payments/?ssl_txn_auth_token=rc5FKo1YQV%2Bt0Vk%2F%2F5PGSQAAAY2E3mHg#!/payment-method. At checkout, specify “Scholarship” in the “Select Donation” field, then type in “Luvisi Scholarship” in the “Description” field.

    Checks can be made to Calistoga Joint Unified School District with “Luvisi Scholarship Fund” in the memo line. Those can be mailed to 1520 Lake Street, Calistoga, CA 94515. For more information, please contact Carla Surber at csurber@calistogajusd.org. — By David Haviland & Pam Kan-Rice (UCANR)

  • Avocados Get Hot — 4 Things to Consider Next

    It’s been hot and there is leaf damage. Those damaged leaves can protect the tree now and the fruit. Don’t prune the trees until you see the full extent of the damage and can still use those dead leaves to protect the rest of the tree.
    Fruit drop happens soon after, or slowly, depressingly over several weeks after a heat wave. The stem turns brown, cutting off moisture to the fruit, and they drop.

    If you see significant leaf drop in your groves due to excessive heat, the following actions are recommended:

    • As soon as possible, whitewash branches exposed to the sun with special attention paid to branches on the west and south sides of the tree.
    • Trees that lose a significant portion of leaves cannot efficiently move water, therefore restrict irrigation amounts to ensure you avoid creating wet, soggy conditions that can lead to root rot. It’s best to irrigate less frequently and with smaller amounts of water.
    • Do not prune your trees — leave hanging leaves in place to protect the tree from sunburn. Once new tree growth has occurred (in the next 3 – 6 months), pruning can take place on living wood.
    • Adjust fertilization as you would with a frost-damaged tree: reducing the amount of fertilizer until the tree is re-established. If you see signs of a particular nutrient deficiency, adjust fertilization accordingly.— By Ben Faber, UC Cooperative Extension

  • What Nut Growers Can Do to Combat the New Carpophilus Pest

    It seems we are always on the verge of some type of apocalypse, and with the new carpophilus beetle invading California tree nut orchards, there is cause for concern.  Watch this brief California Ag Network interview with UC Riverside CE Entomology Specialist Houston Wilson to learn more about this pest and how to stop it from damaging your crops.

  • UCCE Pear & Grape Field Day, May 28

    UC Cooperative Extension is hosting a Pear and Grape Day on May 28, 2024. This is the first event of its kind and we hope to provide programming like this each year for growers in California’s north coast region. The event will focus on the intersection between pear and wine grape production in the north coast. Presentations will be given by experts from University of California and other trusted organizations. Topics will include: Site Monitoring, Cover Crops, Fungal Pathogens, Common Pathogens, Soil Health, Water Use Efficiency in Perennial Crops, Insect Pests & Vectors and more. Registration is $35 and includes lunch. Space is limited, so please register soon if you wish to attend.

    Registration link:

    https://surveys.ucanr.edu/survey.cfm?surveynumber=42533

    Where and When:

    May 28, 2024

    8am – 11am: Rosetti Orchards, 14200 Old River Rd., Hopland, CA

    11am – 3pm: Campovida Winery, 13601 Old River Rd., Hopland, CA

    Speakers:

    • Monica Cooper – UC Cooperative Extension Viticulture Advisor (Napa)
    • Linda McElwee – Mendocino Resource Conservation District
    • Eskalen Lab – UC Davis Department of Plant Pathology
    • Cindy Kron – UC Cooperative Extension IPM Advisor
    • Chris Chen – UC Cooperative Extension Viticulture Advisor
    • Laura Garza-Diaz – UC Cooperative Extension Water and Climate Change Advisor and more…

  • 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