& Grazing Sheep in Vineyards by Kelly Mulville
G
ood fortune (or perhaps simply a preference for beer over wine in my younger years) resulted in my learning and practicing Holistic Management before I became captivated by the world of wine growing. Although I had studied ecological horticulture in California, it wasn’t until a decade later later,, and back home in the Southwest, that I developed a strong appreciation for wine—which naturally led to a desire to grow grapes. Coming at grape growing with a cerebral hangover from trying to grapple with holism and a formidable amount of ignorance encouraged a little different perspective in my farming approach. Admittedly, Admittedly, a bit of geographical isolation from the major wine growing regions, as the first vineyard I designed and managed was in Southeast Arizona, also played a role, for better or worse, in my learning and methodology. methodology. The memory of my first pilgrimage to California wine country ten years ago is still vivid. Coming out of the drought-plagued Southwest, I was nearly
as awe-inspired by the sight of lush cover crops between vine rows as I was attending a co-ed high school after three years of confinement at an all boys boarding school. For a few minutes I imagined how happy the livestock back home would be to see this feast. Snapping out of my ungulate culinary fantasy, I quickly realized that this crop was destined not for grazing but would be mowed, sprayed, and disced back into bare soil for the summer. But the seed had been set: the potential for using grazing animals as a management tool in viticulture was blatantly obvious.
Tapping the Potential The use of livestock (especially sheep) in vineyards is not a new idea, but even to this day I have yet to come across anyone (including myself) managing grazing animals in vineyards at the potential that seems possible. Vineyard management practices in general have become increasingly mechanized throughout the world. A typical year on a California vineyard (organic or conventional) can require anywhere from twelve to twenty-five tractor passes down each row (roughly 26-34 rows per square acre) for pre-pruning, mowing, disking or spading, spraying, under-vine cultivation and in-row cultivation, fertilization, harvesting and seeding. Organic viticultural practices often require more tractor passes than conventional because mechanical cultivation, as opposed to herbicides, tends to be the tool of choice.
Before, during and after grazing in a block of young vines. The tractor row had previously been cultivated leaving a mass of weeds around the vines in the grow tubes. The vineyard crew was delighted at not having to cultivate this area by hand.
Number 127
CONTINUED ON PAGE 10
Land & Livestock
9
Grazing Sheep in Vineyards continued from page nine
Based on the quality of life I was working towards it was apparent that the mechanical domination in both conventional and organic viticulture would hold little attraction to me. I got into agriculture to creatively and effectively work towards solar-based biological management practices. In order to grow grapes and stay true to my desired quality of life, I needed to create or develop farming practices that reflected these values and produced a triple bottom line. Upon my return back to the Southwest I immediately decided to make the row spacing on the vineyard I was planting too narrow for the farm tractor.. This was an important breakthrough in my introduction to the power tractor of design: there hasn’t been a tractor in that vineyard for ten years and rather than reducing options it was great incentive to develop creative alternatives. Large portions of the world’ world’ss wine growing regions are located in Lambs grazing in early spring. Mediterranean climates. This means that virtually all of the annual rainfall comes during the winter and early spring months with summer and early autumn being almost completely dry dry.. This unique pattern allows for an Dealing with Complexit Complexityy increasingly popular practice of seeding annual cover crops each fall or Grazing vineyards can be a fairly complex process with a number of simply allowing the native vegetation to grow while the grapevines are factors to plan for while managing the tool of livestock. Elements to consider dormant. This helps keep soil in place during the wet season and can aid in when planning include: carrying capacity, capacity, vine/cover crop vigor in specific maintaining soil fertility fertility.. areas, reducing erosion potential, coordinating with winter cultural practices Regardless of a vineyard’s location and what season rains occur, like pruning, grafting and spraying, problem plants, water availability, the areas between and under vine rows need to be managed. Keeping avoiding browse damage at bud break and allowing for flowering of cover in line with my quality of life focus on biological (rather than mechanical) crops (especially beneficial insect hosts). With a little modification the management practices, I have experimented grazing vineyards with cattle, Grazing Plan and Control Chart works very well for both planning livestock chickens and geese, but sheep have been my main focus for both contract moves and recording factors such as pounds of manure and quantity of urine grazing (for clients) and grazing of vineyards that I manage throughout deposited per block and acre. Information is then converted to estimated the year. For the past five years I have been grazing and managing vineyards pounds of elements such as nitrogen, phosphorus and potassium. Many in the coastal areas of central and northern California. vineyards/wineries pay close attention to their soils and how management practices affect wine quality quality.. Providing accurate and relevant information is both an aid to winegrowing practices and broadens awareness to the biological and economic benefits of livestock grazing. The grazing season for vineyards in the north coast region of California is Overview of dependent upon the weather (rainfall timing, amount, and temperature), sheep grazing in the vineyard but can start anytime from November through January and runs until the showing electric grapevines start to bud out, which can be from the middle of February until the first of April. In order to keep things simple and avoid overstocking, net fencing animal numbers are determined based on an early bud break date (time of used to create stock removal), total acres to be grazed, assume slow growth for the entire temporary grazing period, type of cover crop being grown, forage estimates and past paddocks. experience. Stock densities of 150 to 400+ sheep per acre (375-1,000 sheep/ha) and grazing periods no longer than three days provide effective animal impact and reduce the undesirable tendency for sheep to chew on the dormant vines. Generally each paddock receives only one grazing during the grazing period unless it is desirable to reduce vigor by overgrazing. Controlling sheep in most vineyards is fairly simple using electrified net fencing, polywire or a combination of both. Having sheep trained to a whistle makes the moves impressively fast. Sheep don’t particularly like to be confined to a single vine row (usually six to eight feet or two to three meters wide), and can damage hanging plastic drip hose by running underneath to access forage between rows. Disconnecting drip lines at T’s or elbows tends to reduce the likelihood of serious damage. As for varieties, I primarily use hair/meat sheep such as Katahdins, St Croix, and Dorpers, but suspect that there are many other suitable types out there. So what are the advantages of grazing vineyards as opposed to the more conventional approaches of mowing, herbicides, tilling, etc.? Following is a list of some of the benefits I’ve experienced over the past few years: 10
Land & Livestock
September / October 2009
Economic:
• Reduction in tractor/labor use for mowing, cultivation and fertilization (3 passes), approximate savings of $134/acre ($335/ha) each year in labor labor,, equipment, and fuel costs. • Provides interesting story and draw for marketing and publicity. Ecological: • Improved soil structure through reduction in tractor use (compaction) and beneficial effects of planned grazing. • Improved nutrient cycling by converting vegetation into an effective fertilizer on site. • Lower pollution levels through reduced tractor use. • Sheep tend to attract birds including turkeys and blackbirds. • Reduced impact on beneficial insects and habit over conventional practices. Social: • Improved neighbor and community relations due to less noise and pollution (this depends, of course, on the flock being well controlled!). Neighbors have become clients after observing the process. • Aesthetically pleasing to see sheep grazing contently in the vines. • More enjoyable form of management for myself. • As opposed to tractors, sheep are self-replicating, can be completely and directly powered by weeds, aid in carbon sequestration, and pair well with red wine.
Contract Grazing
to prevail in January and February. February. I raise sheep without the use of any commercial wormers to avoid any negative effects on the mineral cycle (and the sheep!) and only graze vineyards that use organic or biodynamic practices. Some of the main challenges are economic and design issues. As one might expect these are directly related. Although I consider the rates for my grazing services to be very reasonable, they can still cost the vineyard more than their normal practices. Most clients feel the overall benefits outweigh this discrepancy. discrepancy. For long-term viability,, however, this issue needs to be addressed. The obvious weak link in viability this scenario is that just as cover crop growth starts to pickup as the weather warms, the sheep are removed from the vineyard to avoid grazing the tender new growth of the vines. It’s not uncommon to see late spring cover crops two to four feet tall destined for mowing and discing. Ultimately this is a design problem—vineyards are engineered for machines rather than designed for grazing. In addressing these issues I have found the principles of Holistic Management to be invaluable in developing and guiding a design process that can lead to a much more sustainable approach to wine growing. How we go about designing existing and new vineyards to be managed more effectively and economically with livestock will be the focus of my next article. Kelly Mulville is a Certified Educator who lives in Valley Ford, California. He can be reached at:
[email protected] or 707/431-8060.
Contract grazing on vineyards is usually charged on a per head basis. This rate is determined by terrain, distance from home, layout, amount of assistance provided by the vineyard crew crew,, and a number of other factors. This past winter my rate varied between $.78/sheep/day to $1.60/sheep/day plus a hauling fee. As part of the contract, I meet with the vineyard manager or foreman and work out a grazing plan based on the particular needs of each vineyard. At the end of the season, a completed grazing plan is provided with the actual moves, management notes, and manure and urine estimates per block. Most of the moves are done alone or with an assistant, although I have trained onsite staff to do these moves as well. The grazing season (in the vineyard itself) can be as short as 45 days and as long as 100 days or more.
Vineyard grazing in early January at the start of the rainy season.
Lessons Learned For the most part my experiences with grazing vines over the past five years have been positive and very educational. During that time I have only lost one sheep to a predator (mountain lion) and one to the electric fence (got tangled up during the night). In addition to the occasional broken irrigation tube, at times sheep will chew on young grapevine spurs and canes. This seems to be indicative of a lack of dry matter in their diet and has only been a problem for a couple of weeks in one year. I have lambed out in the vines with very few problems in spite of the cold and wet conditions that tend Sheep grazing in vineyard. Sheep quickly adapt to the obstacles of trellis wires and drip tubing, moving between rows with relative ease.
Shortly after sheep have been removed in late winter.
Number 127
Land & Livestock
11
