Tag: almond rootstocks

  • Start With the Conversation That Determines Your Orchard’s Future

    Planting an almond orchard has never been a simple decision. But in today’s margin-tight environment, the choice of rootstock and variety combination is more than an agronomic preference — it is a 20- to 25-year business decision that can shape profitability, harvest efficiency, marketability and long-term risk.

    That was the focus of a grower-facing discussion moderated by Almond Board of California’s Michael Roots, with perspectives from Dave Phippen of Travaille and Phippen, Duarte Nursery’s John Arellano and grower Brandon Ribiero, at the 2026 Almond Crack Out event.

    For growers, the main message was clear. Do not make a planting decision in isolation. A new orchard should begin with a practical, sometimes uncomfortable, conversation about water, soil, rootstock, variety, harvest timing, market demand and, most importantly, economics.

    “Know Your Breakeven Cost Per Pound”

    Ribiero put the economics plainly when he said growers should “know your breakeven cost per pound.”

    That calculation should sit at the center of every planting conversation. Ribiero described it as a simple equation of cost divided by yield. If a grower expects production costs of $3,500 per acre and assumes 2,500 pounds per acre, the breakeven is about $1.40 per pound. If debt, land costs or other obligations push total costs to $4,500 per acre at the same yield, that breakeven rises to $1.80 per pound.

    That difference matters. In a market where prices can move quickly and margins can narrow, the wrong yield assumption, or the wrong rootstock and variety combination for a site, can make an orchard difficult to carry through the low points of the price cycle.

    Ribiero also warned that growers cannot always “save their way to prosperity.” Trimming some costs may help at the margins, but yield is often what moves the breakeven number in a meaningful way. That makes variety performance, rootstock fit and realistic production expectations central to the decision.

    Start With Water, Soil and Site Limitations

    Before selecting a variety, Ribiero said growers should first understand “all things water” — supply, quality and rights. Without water, he noted, the rest of the planting plan loses its foundation.

    From there, the conversation moves to soil. The right rootstock depends on what the site needs most, including vigor, anchorage, salt tolerance, disease resistance, replant tolerance or other characteristics. Prior Almond Board coverage of rootstock selection has emphasized the same point. Growers should identify a site’s limitations first, then select a rootstock that helps address the biggest risks.

    That means soil tests, water quality information, local grower experience and advisor input should all be part of the planning process. Once trees are planted, growers can adjust irrigation and fertility programs, but they cannot easily redo rootstock selection, variety choice or pre-plant soil preparation.

    Bring the Right People Into the Conversation Early

    Roots framed the panel around a gap that often appears in orchard planning. Growers may talk with a nursery early, but the handler is sometimes brought in after planting decisions are already made, or never at all. The panelists encouraged growers to widen the conversation before committing to trees.

    That group should include the nursery, handler, pest control adviser, neighboring growers and other trusted advisors who understand the region. Arellano said a nursery representative should be prepared to answer questions across rootstock, variety, fit for the site and how the planting will work operationally. If he does not have an answer, he said, the next step is finding someone who does.

    Ribiero said he often asks similar questions of different people one-on-one, looking for patterns in the answers. Where the advice is consistent, growers gain confidence. Where there are outliers, that is where the next question should be asked.

    Marketability Should Not Be an Afterthought

    Phippen brought the handler perspective into sharp focus. A variety may look attractive on paper, and a nursery may be able to supply the trees, but the buying public ultimately determines how that almond is valued. Market classification, quality expectations, defects, customer preferences and regional demand all matter.

    For Phippen, that means the marketing team should be part of the decision-making process. They can help growers understand what is moving well, what may be oversupplied and what buyers are asking for. A grower may be able to produce a variety, but the better question is whether the market wants it, and at what price.

    That conversation is especially important because handlers may serve different customers and markets. Quality tolerance, product form, timing and buyer preference can vary. A variety that fits one handler’s program may not be the right fit for another.

    Do Not Overcomplicate the Orchard

    One of Ribiero’s lessons from experience was the value of simplicity. He described a planting with multiple varieties intended to hedge risk around bloom, pollination and market movement. In practice, that complexity created harvest inefficiency without delivering a better return.

    His takeaway for growers was direct. Do not overthink it. A planting plan that is efficient, repeatable and well-matched to the site may provide more long-term value than one built around too many assumptions. Simplicity can reduce operational headaches and make it easier to scale what works.

    Pre-Plant Work Is the Last Chance to Get Some Things Right

    The panel also emphasized the importance of pre-plant groundwork and amendments. Ribiero noted that once an orchard is planted, it is difficult to incorporate materials into the active root zone. If a site needs amendments such as lime, gypsum, sulfur or compost, pre-plant is often the best opportunity to get them where they need to be.

    That point ties directly back to economics. A grower may be tempted to trim development costs up front, but those savings can become expensive if poor preparation limits tree performance for the life of the orchard.

    A Grower’s Pre-Planting Checklist

    • Calculate your breakeven cost per pound using realistic cost and yield assumptions.
    • Confirm water supply, water quality and water rights before moving deeper into planning.
    • Match rootstock to soil conditions, site limitations and long-term orchard goals.
    • Ask your handler how the variety fits current and future market needs.
    • Talk with neighboring growers who have experience with similar soils, water and varieties.
    • Include your PCA, nursery representative, handler and trusted advisors early.
    • Review independent field data and regional trial information where available.
    • Keep the orchard design practical for harvest timing, equipment and labor efficiency.
    • Complete needed soil preparation and amendments before planting.

    The Bottom Line

    Choosing an almond rootstock and variety combination is not just a horticultural decision. It is a business plan, a risk-management strategy and a long-term commitment to a specific site. The most successful planting decisions begin before the nursery order is placed, with honest conversations about what the orchard must produce, what the market will reward and what the grower can afford.

    For growers considering a new planting, Ribiero’s advice is a practical place to start. Know your breakeven cost per pound. From there, every other decision — water, soil, rootstock, variety, marketability and orchard design — should help answer one question. Can this orchard make money through the full price cycle? — Story Contributed by the Almond Board of California

  • Annihilating Nematodes in the Tree Nut Orchard

    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 on March 24-26, 2026. Participants 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. 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 two 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.

    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.

    Mauricio de Almeida led the tour group around the almond, stone fruit, citrus, pomegranate, and retail table grape plants at the Nursery. Photo credit: Diana Gutierrez

    What is gnawing 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 the soft tissue of plant roots. The adults do not feed on plants.

    Another larva that Burchell manages 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.

    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.

    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 considered endemic to Florida before 2018.

    After a visit to the Cobblestone citrus packing plant, the tour group boarded the bus a final time to return to the Kearney Agricultural Research Center and ate sandwiches for lunch.  They then rode on a tram to visit different field research plots at the Center.

    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.

    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 indoors on the following two days.  — by Nancy Power, Assistant Editor

  • ‘Demo 57 Orchard’ Near Los Banos Showcases 57 Almond Variety and Rootstock Combinations

    A new almond demonstration orchard featuring 57 combinations of varieties and rootstocks has been planted near Los Banos to help growers evaluate planting decisions for the next generation of orchards.

    Known as “Demo 57,” the RPAC Variety & Rootstock Demo Orchard was planted this year adjacent to the RPAC and PAPC facilities, allowing visiting growers to easily walk through the orchard and observe how different combinations perform over time.

    The project was designed so growers can evaluate today’s commercial varieties from prominent tree nurseries alongside newer selections and rootstocks that may shape future almond plantings.

    The orchard was planted in the same year PAPC founder and longtime grower Louie Parreira will celebrate his 100th birthday, a milestone that highlights how much almond production has evolved over the past several generations.  Louie’s son, David Parreira, reflected on how orchards were planted when earlier generations of the family first entered the almond business.

    “When my father and grandfather planted their first almonds, they were on a 24-foot square spacing, about 75 trees per acre. They planted four rows of Nonpareil, then two rows of Mission, then four rows of Nonpareil and two rows of Davey and so on. I don’t think they put much fertilizer on and irrigated only when the trees looked stressed. They were happy to make 500 pounds per acre. Harvest was all by hand and the beekeepers paid the grower to bring bees in so they could make honey. Obviously, almond production has changed a lot!”

    Almond grower and RPAC partner Dennis Soares, who entered the almond industry after two decades in the cotton business, said the industry has changed dramatically since he planted his first orchards.

    “Almond prices were around 75 cents a pound when I planted my first almonds in 1999. Coming from the cotton business, we learned some lessons the hard way about planting the wrong varieties, rootstocks and spacings, like planting Wood Colony at 18-foot spacing.

    “Today plentiful information is available to growers, and making the right decisions is critical when planting a new orchard.  This demo orchard gives growers a chance to see many different combinations and evaluate what might work best for their operation.”

    Soares noted the project also benefits from agronomic support from David Doll, widely known in the industry as the Almond Doctor.

    “Working with David Doll on agronomic support has been invaluable. He provides a tremendous amount of information and stays closely connected with the almond growing community around the world.”

    The project was developed in collaboration with leading nursery partners supplying genetics and planting material.

    John Duarte, President of Duarte Nursery, expressed that “we appreciate RPAC providing nurseries this opportunity to put forward our newest ideas and genetics. For our planting, we included Yorizane high-topped containerized trees on Bright’s Hybrid 5. We believe that this new orchard system will be the highest production and most efficient almond orchard to date. Time will tell. Growers will see it firsthand.”

    “Rootstock selection plays a major role in long-term orchard performance,” said Seana Day, CEO of Dave Wilson Nursery. “Having a demonstration site like this allows growers to compare combinations and better understand how they may perform in commercial plantings. We appreciate RPAC bringing together multiple nursery partners to make this possible.”

    “New almond varieties and rootstocks are coming to market faster than ever, and growers need reliable ways to evaluate them,” said Tom Burchell, owner of Burchell Nursery. “This orchard gives the industry a place to see how different combinations perform side by side in the same environment. We are proud to partner with RPAC on a project that will provide valuable insight for growers across California.”

    In addition to the variety and rootstock trials, the orchard includes a hedgerow planted with ten species of California native plants designed to demonstrate how habitat plantings may support beneficial insects in almond orchards.

    The Demo 57 Orchard is expected to serve as a site for future grower visits and field discussions as the different combinations develop. — Story by RPAC LLC