Golden Mussels have been a silent threat California growers since they arrived in the Delta in 2024. These mollusks reproduce at an alarming rate and don’t require saltwater, meaning they are now clogging up irrigation systems and depriving crops of an already scarce water supply. Jason McKee from Greenleaf Ag spoke with Matthew Malcolm from Malcolm Media Ag Publishing to discuss this latest threat to orchards. Watch this quick video and learn more in Pacific Nut Producer Magazine.
Category: Featured Post
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California Water Alliance Fights for Access to Growers
Getting the water needed for growers to produce their crops is always an issue in California. Despite the water being available, getting it moved to rural communities is hindered by state politics. California Water Alliance CEO William Bourdeau spoke to Matthew Malcolm at Malcolm Media Ag Publishing to go over the challenges growers face and what is being done to help. Watch this quick video and learn more in Pacific Nut Producer Magazine.
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How Pistachios Created a New Word in Mexico
American Pistachio Growers is marketing at the international level, and it’s bearing fruit across the globe. This includes Mexico, where excitement over pistachios resulted in a new word in the country’s vocabulary. Ines Masallach from Imalinx spoke with Matthew Malcolm about how American pistachios have exploded onto the Mexican market. Watch this quick video and learn more in Pacific Nut Producer Magazine.
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Duarte Nursery Harvest Demo Showcases Future of Almond Farming
Duarte Nursery brought almond growers and industry professionals together at its DeWitt Ranch in Modesto for a hands-on look at the future of almond farming. Director of Farming Isaac Duarte discusses the ranch’s high-density Yorizane almonds, catch-frame harvesting technology, orchard design and the data helping growers build more productive, longer-lasting orchards.
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New Products Being Developed to Sell Oregon Hazelnuts
George Packing Company is looking at new products, from spreads to confectioneries, to market and sell Oregon hazelnuts. These efforts are enabling consumers to enjoy hazelnuts in ways not previously imagined. Northwest Hazelnut Company Sales Director Aaron McGraw spoke with Matthew Malcolm from Pacific Nut Producer about some of the latest goods coming out of R&D. Watch this quick video and read more in Pacific Nut Producer Magazine.Please thank this video’s sponsor George Packing Company for their industry support.
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Common Tree Disease May Contribute to Reduced Orchard Longevity
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
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Blue Diamond Releases Crop Progress Report
Blue Diamond Growers release its monthly crop progress report, noting that harvesting conditions began earlier this year due to the impact of the weather.
Warm summer temperatures dominated the conditions in California’s Central Valley during much of July, with a significant heat wave developing during the final week of the period. Daily maximum temperatures ranged predominately between the mid- and upper 90’s to just over 100 degrees with highest temperatures reported in the southern San Joaquin Valley. Morning lows exhibited greater variability, with readings ranging from the low 50’s to lower 70’s, depending on the degree of cloud cover each morning. Temperatures were amplified by monsoonal moisture traveling northward, bringing occasionally cloudy skies and increased humidity. Increasing daytime temperatures materialized in the final days of the period, marking the start of a significant heat wave. Temperatures were reported to be between 102 to 105 degrees, with higher temperatures forecast for the first week of August.
The annual return of summertime monsoon flows stirred a bit of apprehension among California’s almond growers, as memories of the challenging 2025 harvest season were rekindled. With that in mind, growers and huller/sheller operators alike worked to complete final pre-harvest tasks during July, focusing on crop maturity that is running well ahead of normal.
Insect and vegetation management were prime considerations during the period. As noted in our previous report, treatments to protect early harvesting varieties from damage by navel orangeworm were initiated in June, causing the early or advanced crop and pest development. As the crop continues to develop, secondary treatments, intended to catch the insect’s next generation and protect mid and later maturing varieties, were completed in July. As a reflection of the year’s advanced crop development, second treatments have been conducted in roughly the same time frame that initial applications would have been in “normal” years.
As for other pest issues, observers are reporting increased population of web-spinning mites in the Sacramento and southern San Joaquin Valleys. Control at this stage of crop development presents several challenges and the forecast heat wave promises to expand existing infestations. Treatments targeting almond-damaging ant species have also been performed, including second applications in cases with particularly high populations.
Observers are reporting widespread instances of red blotch infections in orchards throughout the Central Valley. As may be seen in the photo accompanying this report, if untreated, red blotch can cause severe foliar damage. However, symptoms of this new fungal disease do not appear until 30 to 40 days after infection. Easily spread by airborne spores that are activated by rain events, and potentially by irrigation, this disease spread from a single orchard in Merced County in 2024 to most of the Central Valley by 2025. Orchards that did not receive adequate protection, or any treatments at all are presenting significant symptoms, with the worst infections beginning to defoliate the trees. This is especially problematic in orchards that have been abandoned. Leaf rust, which follows a similar symptomology, has also been observed.
After delaying or deferring mower passes during the growing season to control costs, vegetation management on the orchard floor became particularly important during the period. Growers must provide for a clean, firm soil surface within the orchard middles (the area between the tree rows), to facilitate an efficient harvest. Where warranted, treatments to control weed regrowth, followed by flail mowers running close to the soil surface, provide the best conditions for a clean harvest.
Crop maturity also made irrigation management a focal point. Machinery passing through the orchards must be timed between irrigations to prevent rutting of the surface. For those working to employ regulated deficit irrigation (RDI) described in our previous report, the hotter temperatures complicate grower decisions. Under RDI, growers reduce irrigation to one-half of the orchard’s consumptive use for a two-week period at the initiation of hull split. Keeping in mind that water consumption increases as temperatures rise, in extreme cases, normal irrigation scheduling can result in one-half of consumptive use. For those with orchards ready for harvest, water must also be withheld to prevent bark damage during shaking.
Owing to the advanced crop maturity, harvest operations of the 2026 crop were launched in mid-July. Observers reported the shakers entered the first orchard on July 10 in western Colusa County. Shakers began working in other advanced plantings along the west side of the Sacramento and San Joaquin valleys during the week of July 12 and the first crop to be picked up was delivered to huller/shellers during the week of July 19. For those along the east side and along the Highway 99 corridor, shaking of advanced blocks is expected to begin during the first week of August.
Growers and observers have noted that hulls have begun splitting in several pollinator varieties, indicating a potentially compressed harvest. However, how the crop will flow though huller/shellers will be determined as more crop arrives in the first weeks of August. Observers have noted thick hulls in many orchards that can potentially reduce flow rates during hulling.
— Story by Mel Machado, Blue Diamond Growers
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Madera County Seeks Pistachio Grower Input
The Madera County Ag Commissioner’s office is gathering data to determine if the pistachio crop has been damaged due to weather and pollination earlier this year. They are hearing reports of low yields and lots of blanks in the current pistachio crop and would appreicate the filling out of this survey form.
The survey form can be downloaded here.
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Can Growers Store Carbon by Changing their Water?
What if Central Valley Farmers could sequester carbon in their soil by only changing how they treat their irrigation water? That is the question driving a new $500,000 study at Fresno State. If 400,000 acres — 10% of the irrigated acres in California — adopted this practice, over 30 million tons of CO2 could be stored in soil through the water every year, as estimated by the research study’s hypothesis. Currently, less than 1% of the acreage in California is using it.
“Soil health is what brought me to California, and this study is exactly the kind of work I came here to do. A simple change to water treatment could have a meaningful impact on soil health and carbon sequestration, and this research will help us understand that potential,” said Dr. Sangeeta Bansal, assistant professor of plant science at Fresno State and the principal investigator.
The study is the largest and longest farm-scale investigation of CO2 in water treatment ever conducted, spanning three years on six working pistachio farms in California’s Central Valley. The California Energy Commission provided primary funding, with support from F3 Innovate.
ECO2MIX, a Fresno-based agriculture company, is providing the water treatment for the study. Their equipment dissolves CO2 into irrigation water to produce carbonic acid, primarily to adjust water pH.
“I started ECO2MIX because I saw the damage sulfuric acid was causing to farms and people, and I knew there had to be a better solution, and carbonic acid was exactly that. This study will finally help us understand the additional benefits after water treatment. If this can sequester carbon across the Central Valley through the water, that is a big deal for California sustainability,” said Waldo Moraga, CEO and President of ECO2MIX.
High-pH irrigation water is common throughout the Central Valley and affects the health of soil and plants. Correcting water pH addresses many problems simultaneously. Carbonic acid also offers a safety advantage over current practices. Other acids are corrosive to equipment and require specialized handling and safety. On the other hand, carbonic acid, the same compound that gives sparkling water its bubbles, is safe to handle.
“We are always evaluating what tools are available to us as farmers and what they can do for our operation. If the water we are already using can do more for the soil and increase profitability, we want to know about it,” said Joe Coelho, a farmer participating in the research and the Director of Sustainability and Member Outreach for American Pistachio Growers.
About ECO2MIX
ECO2MIX provides water pH control as a service by dissolving CO2 in water. The company designs, installs, and operates on-site reactors that treat irrigation water, which supports nutrient availability and efficient irrigation with additional soil health and sustainability benefits. ECO2MIX serves production agriculture and golf customers across high-pH water regions of the United States. For more information, visit www.eco2mix.com. For interviews or farm visits, contact Waldo Moraga at cherbert@eco2mix.com or call 559-321-7917.
