Recent studies conducted by scientists at UCCE and CSU Bakersfield demonstrate that a common disease prevalent in vineyards and orchards may impact long-term orchard longevity of almonds in the southern San Joaquin Valley.Almond orchards with a high incidence of crown gall, a disease caused by a ubiquitous soilborne pathogen, exhibit high rates of tree failure caused by a newly identified wood rotting disease.
Crown gall is common in walnut and almond orchards and can be readily identified by the tumors it induces on the roots and crowns of trees. Unless severe, crown gall generally does not cause tree mortality, but may limit tree size, thus affecting overall yield.Growers with crown gall-affected orchards often replant young trees that exhibit girdling by the tumors but leave mature trees untreated. Within the past decade, however, growers have noticed heightened prevalence of tree mortality due to butt rot in crown gall-affected almond orchards. The butt rot disease is caused by an introduced fungal pathogen, Ganoderma adspersum, that was first reported in California in 2016.
From 2024 through 2026, UCCE researchers have surveyed over 23,000 almond trees in Kern and Tulare Counties, documenting prevalence of both butt rot and crown gall.Molecular identification of the butt rot pathogen in each surveyed orchard was conducted by scientists at CSU Bakersfield. The study found that Ganoderma adspersum was the only species of Ganoderma isolated in all surveyed orchards. Additionally, the results indicated that orchards with crown gall were six times more likely to have butt rot disease. Trees with historic or active signs of butt rot also exhibited 1.5 times the mortality rate of healthy trees over a 26-month survey period.
The results of this work demonstrate that the introduction of the new butt rot pathogen may elevate the importance of crown gall as a predictor of orchard longevity. The implication of this finding is that the planting of crown gall-free rootstocks during orchard establishment may be key to future reduction of risk from G. adspersum. Similarly, Mohammad Yaghmour and Elizabeth Fichtner, Farm Advisors in Kern and Tulare Counties, respectively, found that crown gall was also associated with increased incidence of thousand cankers disease on walnut.Fichtner has also reported that crown gall is related to heightened root predation by ten-lined June beetle on walnut.
The current study was conducted with support from the Almond Board of California and as a collaborative effort between UCCE scientists including Elizabeth Fichtner, Santosh Bhandari, Mohammad Yaghmour, and Raymond Mireles, and CSU Bakersfield Professor Isolde Francis and Chance Kophamer, graduate student. — Story by Elizabeth J. Fichtner, UC Ag and Natural Resources
California and Arizona cantaloupe growers in the southern desert production region report that current short-supply conditions are significant but temporary.
“While weather-related production challenges have impacted the desert growing region, approximately 70 percent of California’s cantaloupe crop is produced in the San Joaquin Valley, where harvest is expected to begin by the June 29, which is right on schedule,” said Garrett Patricio, President of Classic Fruit Company and chairman of the California Cantaloupe Advisory Board, who stressed shippers are expecting promotable volume to be available by early July.”
In the meantime, unusual weather patterns have severely impacted melon production in California’s Imperial Valley and the Yuma, Ariz. growing region. Growers expect extremely limited supplies of all melon varieties, including cantaloupe, during the next two weeks.
“I’ve never seen anything like this in my more than 30 years of growing cantaloupe,” said Barry Zwillinger owner of Legend Produce. “We would love to be able to fill retail orders at any price, but at the moment we simply do not have the volume available.”
Zwillinger explained that a combination of unusual weather conditions contributed to the shortage. Warmer-than-normal winter temperatures and the absence of freezing weather allowed pest populations to increase significantly. This was followed by an exceptionally warm spring, causing harvest to begin nearly two weeks earlier than normal.
“Spring harvest started out fantastic, but as the season progressed, we noticed plants becoming weaker, and yields in many fields declined by as much as 40 to 60 percent,” Zwillinger said. “Those conditions have led to the supply gap we’re experiencing today, with very few melons available over the next couple of weeks.”
Patricio emphasized that growing conditions in California’s San Joaquin Valley have been considerably more stable, and harvest timing is expected to be normal.
“The good news is that we expect strong cantaloupe volume beginning in early July and continuing throughout the remainder of the summer,” Patricio said. “Consumers and retailers can look forward to a steady supply of high-quality California cantaloupes once the San Joaquin Valley season gets underway.”
About 75 percent of all cantaloupes consumed in the United States are grown in California. As the San Joaquin Valley harvest gets underway, the California Cantaloupe Advisory Board is launching an expanded consumer marketing campaign designed to drive demand throughout the summer season. The program includes digital advertising, retail support materials, influencer partnerships and a strong emphasis on reaching younger Gen Z consumers through social media platforms.
“California growers are looking forward to a great summer season with an abundant supply of high-quality cantaloupes,” said Patricio. “We encourage retailers and consumers to follow our social media channels on Instagram, Facebook, TikTok and X for selecting and eating tips, nutrition information and a lot of fun and engaging content from California cantaloupe growers.”
“We appreciate the patience and support of our retail partners during this short transition period and look forward to supplying promotable volumes throughout the remainder of the summer,” said Patricio. — Story contributed by the California Cantaloupe Advisory Board
Farmer John Chandler lamented the loss of methyl bromide for replanting an orchard or vineyard. Photo credit: Diana Gutierrez
Andreas Westphal, scientist at Kearney Agricultural Research and Extension Center in the San Joaquin Valley, organized a soil plant pathology conference that was held late last month. Growers from as far away as Virginia came to learn about the latest research findings.
Chandler Farms
The first day of the conference was a field tour to three sites and then Kearney itself. After meeting at Kearney, the participants rode on a tour bus to Chandler Farms in Selma. John Chandler, his brother Tom and their father, Bill operate a diversified farm that includes almonds, grapes and citrus.
Soil Fumigants
The Chandlers typically change out one field per year. John lamented the loss of methyl bromide for replanting an orchard or vineyard. He now uses Telone, which he finds “has less effect but still works.”
He always contracts out his Telone application because it requires special training. He has the contractor put tarps over it, beyond the usual seal — to prevent off-gassing — but he says, “It’s not worth it to get acres of plastic.” The tarps add about $1000/acre to the cost.
Westphal explained, though, that Telone is becoming more difficult to use because of a new restriction in the amount of Telone allowed plus a requirement that the fumigant be applied with lots of water. The new regulations say that the soil has to be wet to 2 feet depth. If the soil is bone dry, three inches of water must be added within 72 hours before applying the fumigant.
However, the excess water makes it hard to get a tractor through the field. Also, the fumigant does not move well through water, as it is made to move through air. Lastly, the Telone stays in wet soil longer before vaporizing off, which may make it toxic to plants.
Nematodes
Chandler said that his farm has nematodes — the microscopic roundworms that feed on plant roots. His soil has root-knot, lesion, ring and citrus types of nematodes.
When he can afford it, he fallows the land for a year or two instead of fumigating, but he says that fumigation gives the plants the best chance to get started. Once the crop is established, he notes, there are few tools for nematode adjustment.
In his Ruby Red grape concentrate vineyard, Chandler finds that ring nematodes like the wettest part, whereas other types of nematodes prefer the edges, where they feed on the fresh, new roots. Ring nematodes, he finds, like pure sand, but root knot nematodes thrive most in clay soil with good secondary structure.
The tour participants had many more questions for Chandler, but to stay on schedule, Westphal guided everyone back onto the tour bus.
Burchell Nursery
The second stop was Burchell Nursery in Fowler, where Mauricio De Almeida led the group around the almond, stone fruit, citrus, pomegranate, and retail table grape plants.
What Is Eating the Plant Roots?
Almeida said that, as in all greenhouses, the water, heat and humidity may induce root rot and fungus gnats. The fungus gnat larvae eat soft tissue of the plant roots. The adults do not feed on plants.
Another larva that needs to be managed is that of the European pepper moth. The caterpillars girdle the plant stem below the soil line.
The root rot and insect pests occur even though the potting media — made of peat, bark, wood fiber and sometimes Perlite — comes pasteurized. The nursery uses Nemasys® beneficial nematodes to manage the larval insect pests.
Citrus
Almeida explained that Burchell Nursery started growing citrus in 2010. They grew the citrus indoors to protect the trees from the Asian citrus psyllid. Westphal remarked that if you grow bareroot trees in the field, the soil must be certified nematode-free or else the trees themselves must get tested for nematodes. He also said that you cannot fumigate after pulling up the plants because the fumigant would kill the tree.
Among other species, Burchell Nursery sells commercial almond trees, including some cultivars they developed themselves. Photo credit: Tiffany Baiocchi
Almonds
In almonds, Bright’s Hybrid 5, Hansen and Viking rootstocks and Shasta scions resist root-knot nematode. Viking and Shasta also tolerate ring nematodes. Bright’s Hybrid also has low susceptibility to root lesion nematodes. In susceptible varieties, root-lesion nematodes create lesions that can lead to secondary infections like bacterial canker.
The visitors got to see the Cornerstone cultivar of Prunus rootstock, developed by Burchell Nursery to resist the root knot nematodes Meloidogyne javanica and M. incognita. Used as rootstock for almond and stone fruits, Cornerstone is also less sensitive to crown gall, caused by Agrobacterium tumefaciens.
Developed by Burchell Nursery, the Cornerstone cultivar of Prunus rootstock is resistant to the root knot nematodes Meloidogyne javanica and M. incognita and less sensitive than other rootstocks to crown gall, caused by Agrobacterium tumefaciens. Cornerstone can be used as rootstock for almond and stone fruits. Photo credit: Tiffany Baiocchi
Unfortunately, in both Kern and Merced counties (but not Fresno County where the tour took place), in 2018 a root-knot nematode from Florida, Meloidogyne floridensis, was found in almond trees on Hansen 536 and Bright’s Hybrid 5 rootstocks, where they caused growth decline of the trees. Now considered an A-rated (“highest concern”), quarantined pest in California, it has since been found in South Carolina and Georgia, after being endemic to Florida before 2018.
Levels of Plant Response to Pathogens
Plants can be divided into three groups of responses to nematodes and other pathogens: sensitive, tolerant and resistant. Tolerance allows for high nematode populations, which gives the nematodes more opportunity to have genetic mutations that enable them to overcome the plants’ resistance. Therefore, nematicides should be used in tolerant cultivars to limit the pest population.
Grapevines
In a vineyard section of the research fields, Westphal showed a poster of nematodes in the soil profile. Of the three types of nematodes represented, ring nematodes were found only in the top foot of soil.
By contrast, citrus and pin nematodes were found in each one-foot segment down to 4-5 feet, the deepest tested. The citrus nematode population peaked at 2-3’ depth and pin nematodes peaked at 3-4’ depth. The population of pin nematodes far exceeded those of ring and citrus nematodes at all depths. Fortunately, pin nematodes do not cause much economic damage in grapes.
Westphal also showed a poster of total sugar yield in 2025 of Pinot Gris cultivated on different rootstocks planted in 2023 in nematode-infested soil. The negative impact of nematodes was measured as sugar content of the fruit.
Of the seven commercial grapevine rootstocks tested, Freedom had the highest sugar content. An experimental rootstock had even higher sugar content. Serving as control groups, Chardonnay and Zinfandel rootstock had the lowest sugar content.
“On sensitive rootstock, even a few nematodes are bad,” Westphal remarked. About 85% of all new grapevine plantings are on Freedom rootstock. Freedom’s downside is susceptibility to quick decline, so the search continues for an even better rootstock.
In sugar beets, the exudate from plant roots helps nematodes find the roots. Westphal and colleagues are looking into the possibility of manipulating plants to exude different chemicals that do not attract nematodes.
Walnuts and Almonds
Walnuts are sensitive to some nematodes and resistant to others, but “every plant has its limits,” Westphal said. Walnut soil is treated pre-plant and at-plant at the planting site. Tank water is used to settle the tree in. Salibro® is added to the tank water to form a concentration that kills the nematodes but not the trees. Westphal cautioned growers to not overwater walnuts.
Among other things, Westphal is testing juice from walnut hulls to see if they inhibit nematodes. He noted that ASD (anaerobic soil disinfestation), created by applying nine tons of rice bran per acre, inhibited nematodes somewhat. However, it would not be worth the $6,000/acre price tag for growers.
Westphal is testing whether juice from walnut hulls can inhibit nematodes in almond orchards.
Highly resistant rootstocks can grow without fumigation, with less toxic, affordable nematicides applied. As with citrus, nursery trees must be grown in nematode-free soil, or the trees must be certified before leaving the premises.
Westphal showed the tour participants an almond rootstock test orchard, in which nematode resistance is compared among various commercial and experimental rootstocks. Only the most successful experimental rootstocks make it to the next round of trials, along with the commercial ones for comparison.
Westphal then concluded the field tour. The conference continued in an indoor classroom on the following two days.
The California table grape season is on track to arrive about two weeks early, signaling that grapes from California will be available for promotion longer than previous seasons. Each season begins in the Coachella Valley, where growers are expecting to begin harvesting at the beginning of May this year. An early start to harvesting in the San Joaquin Valley is also expected to begin in mid-June.
“California grapes have always enjoyed a long season, with grapes often being promoted into January, but an early start to the season this year lets retailers get a head start on promotions and providing tasty, healthy, happy Grapes from California to eager customers,” said Commission President Ian LeMay.
For the 2026 season, the Commission is launching an updated global marketing campaign throughout the U.S. and up to 22 export markets, targeting the trade — which includes retailers, wholesalers and importers, as well as primary shoppers — with the objective to drive demand for California table grapes. The updated campaign introduces retailers and consumers to a cast of characters known as the Lunchbox League. The Lunchbox League is a trio of superhero grapes that originate from California, where tasty fuels healthy, and healthy makes happy. Captain Cluster, Munch and Glow are the superheroes who make up the Lunchbox League and serve as the embodiment and personification of all the health benefits, taste, and quality of California grapes.
“This campaign element is exciting because it capitalizes on the scientific perspective published by Dr. John Pezzuto in July 2025, which claimed grapes should be considered a superfood, in order to give the Lunchbox League their superhero status,” said LeMay.
Dr. Pezzuto, Ph.D., D.Sc., is a leading resveratrol and cancer researcher and Dean of the College of Pharmacy and Health Sciences at Western New England University.
To drive demand for California grapes through the season, the commission works with retail partners on a variety of activities such as contests, digital promotions, merchandising, point-of-purchase materials and sampling. For retailers in the U.S. with registered dietitians on staff, the commission Retail RD Program offers an additional way to promote Grapes from California and highlight the health benefits of grapes to shoppers. Retail dietitians can work directly with the commission dietitian team to develop customized promotional activities and educational materials.
“With a healthy crop arriving early and an engaging new campaign with demand-driving materials and activities, the commission is eager to work with retailers throughout the U.S. and around the world to move California table grape volume this season,” said LeMay.
— Story provided by the California Table Grape Commission
The California Table Grape Commission announced a $2.2 million award through the America First Trade Promotion Program to support expanding international marketing efforts to strengthen demand for California table grapes.
“This award through the America First Trade Promotion Program represents a meaningful investment in the continued success of the California table grape industry and the communities the industry supports,” said Commission President Ian LeMay. “We are grateful to the Trump Administration for recognizing the importance of export market development and for providing tools that help American agriculture compete and thrive in global markets. These resources will allow us to expand strategic promotions in key partner countries and ensure consumers around the world continue to choose grapes from California.”
California table grapes are exported to more than 60 countries each year, with international markets representing an important component of industry stability and growth. According to the Commission, funding from this award will support retail initiatives in Australia, Mexico, Canada and the United Kingdom, and reinforce California’s position as a global supplier, while supporting growers, shippers and farming communities throughout the San Joaquin and Coachella valleys.
California table grape growers are doubling the impact of each gift made to the Central California Food Bank between October 20-31 to help provide meals for families facing hunger across the Central Valley.
October is California Farmer and Farmworker Month, a month-long acknowledgement of California’s hardworking farmers and farmworkers. In celebration of the hands that help feed us, every dollar donated during the two-week campaign, up to $15,000, will be matched by California table grape growers. The campaign is designed to raise awareness and provide essential support to sustain food distributions in the San Joaquin Valley. Specifically, funds raised will help strengthen Central California Food Bank’s Farmworker Community Partnership Program across Fresno, Kern, and Tulare Counties.
Central California Food Bank is the largest hunger-relief organization in Central California, serving Fresno, Kern, Kings, Madera, and Tulare counties. In Central California, 1 in 4 adults and 1 in 3 children face food insecurity, which is the limited or uncertain access to adequate food. Through a network of more than 260 member partner agencies, Central California Food Bank distributes nutritious foods to over 320,000 people each month, including more than 100,000 children.
The campaign is a demonstration of California table grape growers’ collective commitment to building thriving communities in the table grape growing regions. “The commission is a service-based organization, and this initiative is a reflection of the commitment of California table grape growers to the communities they live and work in,” said Ian LeMay, commission president.
California table grape growers are once again providing scholarship opportunities to graduating high school seniors from the table grape growing regions of California. Three categories of scholarships are available again in 2026.
Two scholarships are available to field workers and their families. The Field Worker Bridge Scholarship is a $14,500 scholarship for students who will attend two years at a community college and transfer to a four-year university in California. The Field Worker Scholarship is a $25,000 scholarship for students who will attend a four-year university in California. Eligible high school graduates or graduating seniors, or their parent/legal guardian, must have been employed as a field worker in a California table grape vineyard during the 2025 harvest or plan to be employed during the 2026 season to be eligible for the Field Worker Scholarships.
The third scholarship is a $25,000 Agricultural Scholarship available for students interested in building a career in the California table grape industry and investing their undergraduate years of study in academic areas related to the industry. Eligible high school graduates or graduating seniors must pursue a four-year undergraduate degree from a California university in a field of study pertinent to table grapes and be residents of the Coachella or San Joaquin valleys.
Three scholarships from each category are available. Applicants for all scholarships must plan to attend a California college or university. The deadline to apply for all scholarships is Friday, February 6, 2026.
Springtime is an important time for replenishing your vineyard with the essential nutrients lost from the last harvest. Nitrogen-fixing cover crops are a great source for this. But what types of cover crops are best and how do you tell when it’s time to disk them under? Watch this brief interview with Madera County raisin grower and PCA Manuel Marin to find out. Read more in American Vineyard Magazine.
Ag Students at Reedley College Learn how to bottle wine for the first time.
The Plant and Soil Science program at Reedley College offers a wide variety of courses that lead to an Associates of Science Degree or Certification. Students enrolled in a plant and soil science course have the opportunity to engage in numerous industry experiences, including: wine making, field trips to local packing facilities and hearing from Ag industry speakers throughout the school year. The Plant & Soil Science program also provides job opportunities during the school year and the summer. Students in the Program run and operate equipment on the campus farm.
Photo by Matthew Malcolm, American Vineyard Magazine
Fresno, Calif., (August 17, 2017) – Several students from throughout the San Joaquin Valley recently competed at the 69th National High School Finals Rodeo (NHSFR) in Gillette, Wyoming, from July 16 to 22.
Local competitors included Reed Neely, Andee Poole, Chance Strong and CJ Whitney. These individuals represented District 6 of the California High School Rodeo Association (CHSRA), which encompasses Kern through Madera counties. The organization offers 13 events that freshman through senior students may compete in.
Andee Poole
To qualify for the NHSFR, contestants were first required to compete at the state level. To make it to the California High School Finals Rodeo (CHSFR), students had to be ranked in the top five in their district for their respective event. At the state finals, the top four contestants in each event qualify to go on to compete at the NHSFR.
In Wyoming, contestants competed against opponents from throughout the United States, Canada and Australia. Each state or providence is entitled to send up to four competitors in an event. This year, more than 1,600 participated. The NHSFR has become known as the “World’s Largest Rodeo.” The California team placed second overall, behind Texas.
Reed Neely (18 years old), of Clovis, is a student at Clovis East High School. He competed in the saddle bronc, placing fourth overall. Reed followed in the footsteps of his father, Jeff. His mother, Debbie, also has a history in rodeo. Reed is involved with FFA and ranches with his dad.
Reed Neely
Chance Strong (17 years old), of Hanford, is a student at Kings Valley Academy. He competed in bull riding. He began riding sheep at the age of four when his dad got him started in the sport. Outside of competing, Chance spends his time ranching with his stepdad.
CJ Whitney (17 years old), of Visalia, attends Visalia Independent Charter and qualified for the reined cow horse event. CJ got interested in rodeoing through her grandpa. She spends her free time training service dogs.
The National High School Rodeo Association has a strong emphasis on academics. The organization also promotes western heritage, invests in the future of rodeo athletes, teaches leadership, promotes education and encourages family values.
Sponsorships play a large role in the success of the organization’s athletes. Contestants receive support through awards and scholarships. To become a sponsor of the California High School Rodeo Association, contact 209-847-6819 or chsrarodeo@gmail.com.
