This project seeks to develop baseline information for evaluating the potential ecological and economic benefits and challenges of integrating sheep into a vineyard system in Vermont. We have four explicit objectives to explore this integration across the entire integrated system including:
- To measure the soil and other ecological outcomes of sheep integration into vineyards, such as fuel savings and soil health
- To assess the animal outcomes of sheep integration into vineyards
- To understand if grape quality and vine health are affected by sheep integration
- To analyze the economic outcomes and consumer perceptions of sheep-vineyard integration
From an agricultural perspective, winegrowing has long been considered a monoculture system. Vines are planted in a grid, with frequent mowing of row middles and herbicide use/cultivation ensuring bare ground under the vines. However, more recently, there’s been a growing movement to diversify vineyards, increase biodiversity, and improve sustainability. Some of this is done through interplanting with other annual or perennial crops, establishing pollinator habitat, eliminating herbicide use by maintaining vegetation under vine, and/or allowing vegetation in row middles to grow tall. Today, a small but growing body of research is exploring the integration of animals into vineyard systems. Such efforts are part of a wider movement to re-integrate crop and animal systems, historically common, and more recently divided because of the efficiencies of modern agriculture. Research on reintegrating such systems has shown that crop and animal integration provides both environmental and economic benefits. Vermont’s small, yet progressive wine industry has been keen to adopt current best management practices for vineyards, but has not explored the utilization of livestock, which is especially common in vineyard systems in New Zealand. Based on personal conversations with several winegrowing colleagues, there is developing interest in the strategic use of sheep in vineyards. This project aims to examine the potential ecologic and economic benefits of making sheep a component of sustainable vineyard management.
The potential for synergies through seasonal sheep integration into Vermont vineyard systems could prove significant. Historically, it is common in vineyards to frequently mow row middles and apply herbicide or cultivate under the vines. Because of farming conditions specific to the northeast, Cornell University has shown that these practices can have a detrimental effect on both the environment (increased nutrient leaching/greater soil bulk density) and the vines (increased vigor) (Vanden Heuvel 2017). Their recommendation has been to allow native vegetation or cover crops to establish under the vines. However, in-row vegetation and that between rows still requires management. Current methods for doing so are costly, requiring specialized equipment, frequent passes, and high labor inputs, not to mention the negative environmental impacts of fuel consumption and soil compaction. As a result, some growers either choose to stick with herbicides/cultivation or do nothing, which has implications like increased frost risk and damage from mice. Sheep could play a valuable role by offering a sustainable solution to vineyard floor management while at the same time increasing biodiversity in the system. Farmers working with herbicides/cultivation may move to more vegetative cover along with those who already have and both groups may find labor and fuel savings, improved soil health, decreased compaction, increased soil fertility, and increased microbial diversity, not to mention the emotional lift a flock of cute sheep can bring to employees and consumers. In addition, sheep are historically significant to Vermont, with an estimate that by 1836 there were a million sheep in the state (Bazilchuk and Strimbeck 1999). This project has implications that go outside that of Vermont vineyards, with relevance in other vineyards and perennial cropping systems locally, regionally, and beyond.
From a historical perspective, the intimate relationship between livestock and cropping systems is not new. Before the introduction of large-scale agriculture, smaller, diversified farms dominated the landscape where crops and animals were integrated synergistically globally (FAO 2010). Over time, agriculture became more specialized, transitioning crop and livestock production into separate entities, in some cases separated by large distances (Peyraud et al. 2014). Through this decoupling of crop and livestock systems, there have been significant potential productivity gains, but with significant adverse environmental and social externalities (Naylor et al. 2005).
Recent efforts to re-integrate crop and livestock systems have shown great promise to reducing these potential externalities in our global food system (Martin et al. 2016; Wilkins 2008). Existing research on re-integrating crop and livestock systems has found that such reintegration can provide economic benefits to farmers via reduced input costs and farm labor and reduce some environmental impacts including fuel consumption and soil compaction.
These efforts, while ongoing in research particularly related to beef and crop systems, are more recently including vineyards. As vineyards often have inter-row species, which can serve as feed for animals, there has been a small, but growing understanding of the potential opportunities and challenges with integrating animals into vineyard systems at various times. The practice is most pronounced in New Zealand, where there is no shortage of sheep (29 million in 2017 (Statistics New Zealand 2017), and a burgeoning wine industry is now the 15th largest producer in the world. It is estimated by the New Zealand Winegrowers Association that 59% of their growers (95% of all New Zealand winegrowers) are integrating sheep or other livestock into their vineyards at some point in the season (Niles et al. 2018). Such efforts have been widely understudied for their potential benefits and challenges, but recent evidence indicates that the practice can reduce both herbicide applications and mowing in vineyards, providing economic benefits to farmers (Niles et al. 2018). As a result, “wide scale global adoption of integration of sheep into vineyards has the potential to significantly reduce environmental impact” (Niles et al. 2018) and provide reduced costs to growers. However, New Zealand is quite different than the Northeast of the U.S. in these two industries- as both wine and sheep production are largely for export markets (Harrison 2015; New Zealand Winegrowers 2018).
While these efforts are only beginning in the U.S. (for example, small experiments in California (Meadows 2008) and New York (van Zoeren and Vanden Heuvel 2018), there is great opportunity for the practice domestically. In New England, and Vermont in particular, the industry is growing. Within the last twenty years, Vermont has gone from three wineries to over twenty and seen vineyard acreage increase from just a handful of acres to nearly 150. Simultaneously, there is a growing consumer interest in more diversified farming systems, local meat and wine production, and small-scale agricultural development. As such, our research will trial the integration of sheep into a Vermont vineyard to explore the potential initial challenges and benefits to ecological, plant, animal and consumer outcomes. We seek to understand in different climate and market systems the opportunities and challenges for vineyard and livestock producers with re-integrating animals into vineyard systems.
We have broken the project down into four sections: Soil Health and Forage, Animal Outcomes, Grape Outcomes, and Economic and Consumer Outcomes.
Soil Health and Forage
Overseen by technical advisor Juan Alvez, soil health and forage data will be collected and processed as follows:
Composite soils samples within each of three treatments (two with sheep plus a control) will be collected. Each sample will be obtained by combining 15 sub-samples in a clean bucket. After mixing it, a sub-sample will be taken from the mix and placed in a sealed, identified plastic bag, and stored inside a refrigerated cooler to be shipped to UVM Soils Testing Lab for subsequent nutrient and biological testing.
Pre-grazing pasture species within treatments will be visually described and identified; then pasture yield will be estimated via electronic capacitance meter (ECM). The entire plot area will be grazed once the average forage mass reaches an average of 2,400 lb DM/acre, down to 1,300 lb DM/acre within 12 hours, and the animals removed until the next grazing. Before grazing, two, 4×36-inch forage samples will be collected by systematic randomization, by clipping at soil surface with an electric clipper. Samples will be separated into grass, legume, and forb components, dried at 130 F, and weighed to determine botanical composition and obtain another measure of forage yield in addition to ECM measurements.
After each grazing, the area will be clipped so that subsequent measurements of forage are from regrowth, not rejected material of previous grazings.
Experimental design: A completely randomized block design with a min of three replications per block (see scheme below) will help analyze, soil attributes, forage composition, yield, botanical composition and quality, fruit chemistry and quality, prune weight and before and after animal body condition. Each treatment will have a minimum of 1000 sq ft area.
Block 1 Block 2
Block 3 for1 cntrl
for2 for1 cntrl
cntrl for2 for1
(vineyard area for block design will be determined based on farm logistics at beginning of study, as there are multiple possible locations)
Information on animal health will be completed under direct supervision of technical advisor Juan Alvez and will be as follows:
Estimated pasture intake of sheep/lamb: To determine the average pasture DM intake per sheep per day, we can calculate dry matter demand from a percentage of sheep’s body weight by using the following formula: DM demand(lb) = Body weight (lb) x (DMI% Body weight value/100lb, knowing that around 1.9% of their daily intake is for its basal metabolism.
Body Condition Score: Is a 1-5 scale (Thompson and Meyer, 1994), easy and accurate method of estimating the nutritional condition by assessing the amount of muscle and fat covering the backbone and the short ribs of each sheep, which translates into stored energy. Prior to animal handling, we will seek approval from Institutional Animal Care and Use Committee (IACUC).
Within treatment areas, we will look at fruit chemistry and plant vigor on five randomly selected vines to determine if integration of sheep has an affect on either. Fruit chemistry parameters will include pH, titratable acidity, and sugar content (Brix). Likewise, on these same vines, we will measure pruning weight, simply the weight of annual growth that is removed during dormant pruning which serves as a proxy for vine vigor. Shelburne Vineyard will collect and measure these attributes. In addition, at bloom time and again at the start of ripening, we will collect grape leaf petioles for subsequent tissue analysis, giving us a snapshot of vine nutrient status. Petioles will be collected according to guidelines set forth by the Agro-One branch of the Cornell affiliated Dairy One lab and analyses will be performed by the lab.
Economic and consumer outcomes
We will measure potential economic changes in both business structures (sheep and vineyard systems) to understand how integration may affect changes in farm labor, input use, and feed costs. Led by the technical advisor Dr. Meredith Niles, this research will work with both the vineyard and sheep farm to document baseline economic costs in labor associated with sheep and vineyard management, input costs, and (for sheep) feed costs. These baseline measurements, taken from the previous year and prior to sheep integration, will then be compared with measurements taken during the integration period. Key metrics including: 1) man hours of labor (e.g. transport of animals, animal management, fencing, mowing, input applications); 2) input costs (e.g. herbicides or other chemicals, nutrient inputs, water, etc.); and 3) feed and seed costs. Analysis will explore changes in costs before and during integration to calculate the potential costs or savings to both farm systems.
In addition, we will examine preliminary consumer perceptions of sheep integration into vineyard systems. Very little is known about consumer preferences for re-integrated systems. However, animal integration into vineyard systems may elicit varying perspectives on topics including animal welfare, environmental benefits, and food safety. We will conduct surveys of wine consumers and purchases via the Shelburne Vineyard
tasting room on multiple occasions (e.g. when sheep are physically in the vineyard and not) to examine initial perceptions of the practice, consumer preferences, and willingness to pay additional premiums for wine or sheep produced in this way. Prior to surveys, Institutional Review Board approval will be obtained. Surveys will be analyzed using multivariate regression techniques.
This project ended up serving as a proof of concept type effort. Due to lack of resources to reference for our climate and vineyard conditions, and having no personal experience with sheep in vineyards, there was much trial and error. However, after the initial learning curve, it was clear that the sheep-vineyard system would work. Until this project, the utilization of sheep in VT vineyards was only a discussion. Now, with one season completed, the actual potential has been demonstrated. Colleagues are eager to either pursue relationships with existing shepherds or become shepherds themselves in effort to explore this management option themselves.
Key areas of information include paddock design and setup, renewal thinning, manure/nutrient cycling, efficacy of grazing, and preferred grazing vegetation.
As stated earlier, our project ended up being more of a proof of concept than one rich in data. However, this was crucial to determining if grazing sheep in VT vineyards was even possible. Even with a limited flock of sheep and five weeks of grazing, it was clear that the potential for this integrated management is real. We plan to continue these efforts on a larger scale, hosting a bigger flock on more area than we did in the project. Colleagues have also expressed interest in pursuing the integration of sheep in other vineyards as well.
Typically, a vineyard is a stand alone system and mowing is commonplace. With the introduction of sheep, we have added a layer of complexity that gives the land additional purpose and benefits the system as well. We will be able to delay and reduce mowing in the vineyard by at least one pass, which will save money and reduce tractor passes in the vineyard. Because sheep also prefer to graze certain vegetation, we may seed down specific choices which will benefit both the sheep and the vineyard. We also noticed that just having sheep in the vineyard contributed to overall happiness and enjoyment at work. Employees also gained skills in animal husbandry.
Education & Outreach Activities and Participation Summary
News of this project traveled far and wide and reached a broad audience. NBC5 did a feature on their evening broadcast. Seven Days, distributed throughout the state, wrote an article. Meredith and Ethan were interviewed on the Dave Gram Show on WDEV, a radio network in VT. Ethan and Mike’s alma mater, University of Vermont, did a story on their website homepage and also in the fall issue of UVM Quarterly. The project was also picked up by Modern Farmer, an authority on food producers influencing the current state of agriculture.