Rethinking Trellis Viability in the Age of Mechanization

By: Tracey L. Kelley

Initially, when conceptualizing this article, we wanted to present the feasibility, maintenance and costs of the Lyre trellising system.

  However, research and interviews revealed that while it was once a viable choice, evolving production practices, reduced labor availability and other factors require growers to think more strategically. For cost-saving efficiency in the fruit zone, vine vigor and development of the finest product, growers need more modern trellis innovation.

  You know something interesting is about to happen when you contact a subject matter expert about a story angle and he or she says, “Um, that simply won’t work. Here’s why.”  Uh oh…

  What first piqued The Grapevine Magazine’s interest in the Lyre system was visiting American-based vineyards and hearing growers share their enthusiasm for it. Developed in the 1980s by Alain Corbonneau in the Bordeaux region of France, the Lyre trellis trains vines to grow up, allowing more wind and sun into the canopy for greater fruit yields and reduced mildew. It first entered into some mainstream vineyards because of a disaster.

  “The 1990s was a period of questioning canopy management and trellising. This was particularly evident in California, where (growers) were replanting after the AxR debacle,” said Richard Smart, author of Sunlight into Wine and world-renowned viticulturist specializing in canopy management, improving vineyard yield and nutrition management. The referenced debacle was AxR#1, or Aramon Rupestris Ganzin No. 1, a French-American cross rootstock devastated by the louse phylloxera.

  “There was a lot of the Lyre trellis installed in the Napa Valley and thereabouts at that time, probably more than anywhere else in the world that I am aware of,” Smart said. At the time, high-yielding growers in California, Oregon and Washington considered it a viable alternative—as did some in Texas and, to a limited extent, Missouri, New York and North Carolina. It’s a less-popular divided canopy choice where cold injury is common because of the extensive cordon development required. However, that’s not the only issue with it.

  “There may be 6–to–12 foliage wires and two fruiting wires. It’s, therefore, one of the more expensive trellis systems to install,” Smart said. “And its popularity soon waned because of problems with mechanization and subsequently, the effects of trunk disease—although this system is less prone than single curtain vertical shoot positioning (VSP). I hear mixed reports on the ease of mechanical harvesting, although it’s relatively easy to mechanically pre-prune.”

  So here’s one point where our story angle turned: how does a single choice of trellis impact all other aspects of production, labor and cost savings?

Labor+Mechanization=Different Trellis Choices

  “The top three trellis issues we’re asked to help with are labor savings, trellis systems that allow for more mechanization and stronger systems to hold the larger crop loads,” Jeff Miller told The Grapevine Magazine. Jeff Miller is COO of JSC Agricultural Supply, a division of Jim’s Supply based in Bakersfield, California. It manufactures trellising supplies, provides a full line of agricultural equipment and consults with growers about trellis systems and installation.

  A term frequently mentioned in the industry now is “no touch”: vineyards managed by mechanization and technology that reduce reliance on human labor. In France, where agricultural labor receives higher wages than in the United States, there’s an intense demand for advanced no-touch technology. Growers in Australia, Italy and Spain are adapting, too. At the 2017 Unified Wine & Grape Symposium, numerous panel experts—including Mark Krstic of the Australian Wine Research Institute, Aaron Lange of Lange Twins Family Winery and Vineyards in California, and Nick Pehle of Stone Hill Winery in Missouri—detailed the hows and whys of no-touch operations for everything from pruning and shoot thinning to leaf removal and harvest.

  “This is the direction the industry is heading,” Miller said. “It has to. With a shrinking workforce, more competition for labor, changing overtime laws and increasing minimum wage, growers are seeking solutions to limit the amount of labor needed in the vineyards.”

  These essential points circled our story angle back to trellis choices. Craig Macmillian is an ag specialist with Gold Ridge Research Conservation District in Sebastopol, California, who works with landowners to conserve, preserve and improve their properties. A former grower and winemaker, he said it’s not easy or inexpensive to convert horizontally-divided systems to vertical systems to allow for greater mechanization.

  “When I have seen people make a change, they were redeveloping the vineyard,” he said. “While horizontal systems like the Lyre are still excellent choices for high-vigor sites, you can’t pre-prune, prune or harvest mechanically. Most machines are designed for vertical trellises.”

  He went on to say that because both sides of the vine established on a horizontal structure require more touches, it takes additional time to work a block. “So with whatever labor you have, it’s very slow to get through a block. Doubling the amount of labor just isn’t practical. Costs are going up, and growers are paying more per hour, but more importantly, there simply aren’t enough people.”

  Here’s where the angle of this particular story could have easily jumped from the Lyre system and trellising in general to necessary mechanization due to immigration and adverse effect wage issues. In the United States, most farm labor comes from Mexico, but fewer people, in general, want to be involved with such hands-on, backbreaking work. So, while that topic is definitely an important feature to present another time, what’s interesting and more on target in this story is how growers, educators and manufacturers are innovating to accommodate where the industry is now and how planning should evolve to address key challenges before they happen.

Consider All Options for Now…and the Future

  To ensure the most healthy and productive canopy, Smart encourages growers to consider their options down the line, taking into consideration the overall operations of the vineyard.

  “My general preference in today’s market of constrained labor availability and cost is to use the vertically-divided Scott Henry system for cane pruned vines, and the Smart-Dyson for spur pruned vines,” Smart said. “The latter can be mechanically pre-pruned, and both machine-harvest well.” Smart partnered with John Dyson, a California and New York grower, to develop a split canopy system to improve yield and wine quality. Industry experts rely on the system to provide better grape-foliage balance.

  Miller added that “as the grower works to reduce their costs in the field, they’re moving towards a single bi-lateral cordon system 60–66 inches high. The system allows for uniformity to help with mechanization.”

  To new vineyard owners, Macmillian recommends installing the most basic trellis system possible at first. “Then put in a line post that has the ability to have retrofits put on it, so you can put on catch wires, additional catch wires, a crossbar, if that’s how you decide to go. Build up to what your needs eventually will be.”

  For ease of mechanized harvest, he referenced a California grower who established a cross arm that was up to about 18” wide. “While not horizontally divided, it was a way to capture the canopy without having to move the wires, which is what a cross arm will enable someone to do. It allows the canopy to be more open than with catch wires, but not flopping completely.”

  Macmillian also suggests people think about mechanization right from the beginning. “I don’t see that there’s going to be more labor in the future. In order to survive, vineyards are going to have to become increasingly mechanized. This applies to small, medium and large producers.”

What about the sense of community pride when people are involved in pruning, harvest and crush? Many vineyard owners rely on this assistance not only to provide a connection to tradition and as great promotion but also to manage costs more effectively.

  “If someone has a small enough vineyard—we’re talking a couple of acres—and they have that kind of community of friends, neighbors and relatives, hand labor is viable,” Macmillian told The Grapevine Magazine. “However, what I’ve found is most folks are excited to work for a couple of hours, then it’s not fun anymore. So there’s not much acreage you can cover that way. Now, in Europe, for example, domains—such as those in Burgundy, which tend to be very small—have folks from the community who come every year who pick at the end of the day, and that’s it. But we don’t have the same kind of tradition as they do there. And even in Europe, [use of] immigrant vineyard labor is increasing.”

  He added that “if you have a high-vigor site, a divided canopy trellis might initially be the right choice, but economically and logistically, it may not be the right choice. Which means you’ll have to deal with that vigor issue another way, and that’s the problem.”

  Miller said JSC tries to develop products to allow for a slight hybridization in operations, recognizing that while complete trellis retrofitting might not be an option for existing growers—especially those of a certain size—adapting technologies might bridge the gap.

  “In early 2018, JSC partnered with ECO Trellis out of New Zealand to add the ECO/ KLIMA suite of products to our product line,” Miller said. “The KLIMA pruning machine is a cane pruning system that reduces costs during the pruning process. We developed a cross arm that can adapt any existing trellis system over to be compatible with the KLIMA pruning machine. In addition, working with a grower on the Central Coast, we developed an extension that can be added in the early years of a high-wire system to help with the spur positions in the initial development of the vineyard.”

  University of Missouri Extension Services offers a comprehensive article that provides great detail in preparing for mechanized viticulture or preparing an existing vineyard for mechanization. It advises producers to first “develop a working knowledge of the abilities, limitations and requirements of currently available equipment.” Also included in this analysis is the importance of site selection, vineyard design, cultivar selection and trellising.

  “At present, single curtain, cordon-trained systems are the most conducive to full vineyard mechanization. Examples include the high bilateral cordon, mid-wire cordon with VSP and the Smart-Dyson and Ballerina systems. Of these, the former two are often preferred for their simplicity in management, and selection of either should be based upon cultivar growth and bearing habit, anticipated vine size and revenues and other site or regionally-specific considerations.”

  Basic touchstones for existing vineyards include close examination of trunks and cordons, as well as the density of canes and spurs; investigating the cost of repairing or retrofitting the trellis; and reasons for sagging between posts, whether it’s due to falling end assemblies, excessive line post spacing or inadequate tension prior to cordon establishment. U of M Extension offers an extensive checklist for established growers considering more mechanized operations.

Email This Post Email This Post

Leave a Reply

Your email address will not be published. Required fields are marked *