Sustainability outcomes of integrated sheep vineyards systems

Progress report for SW23-949

Project Type: Research and Education
Funds awarded in 2023: $347,696.00
Projected End Date: 03/31/2026
Host Institution Award ID: G306-23-W9981
Grant Recipients: University of California, Davis; Ecdysis Foundation; Community Alliance with Family Farmers; Napa County Resource Conservation District
Region: Western
State: California
Principal Investigator:
Dr. Amelie Gaudin
University of California, Davis
Co-Investigators:
Dr. Elisabeth Forrestel
UC Davis Viticulture and Enology
Dr. Brittney K Goodrich
Cooperative Extension at the University of California, Davis
Dr. Jonathan Lundgren
Ecdysis Foundation
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Project Information

Summary:

Vineyard producers are rapidly adopting regenerative production models to address sustainability challenges arising from input based conventional production. Integrating livestock onto cropland is a key practice in regenerative agriculture, providing opportunities to meet sustainability goals by building soil health, reducing input and labor costs while creating new markets and added value1–5 . Integrated sheep vineyard systems (ISVS) are gaining traction in the coastal regions. However, the lack of systems level data from working farms and knowledge sharing platforms for producers integrating grazing across a co-management gradient (conventional-regenerative) limits our understanding of best management guidelines, as well as the full scope of the potential benefits and tradeoffs associated with ISVS 6,7. With grape systems in California approaching 1M acres (CA’s third highest grossing crop), the need for sustainability impact assessments, best management practices (BMP) guidelines and economic return planning tools for integrated systems is growing. California is also confronting decline in forage with the current drought and vineyards’ understories represent an increasingly important source of forage. The proposed 3-yr study is based on extensive consultation with growers, sheep operators, and previous work by the team to provide a systems level comparison of ISVS practicing winter season grazing (ISVS_WG), winter and summer season grazing (ISVS_WSG) and non-grazed vineyard systems (NG). Our objectives are to 1) establish a landscape scale on-farm participatory research platform to 2) quantify the impacts of grazing and grazing intensities on vineyard soil health, biodiversity, vine health, yields, berry quality, forage quality and input use. This data, along with farmers interview will be used to 3) analyze the economic performance of these viticulture systems and develop a cost-return planning tool. We will 4) identify benefits and potential tradeoffs by evaluating interactions between the chemical, physical, biological, and economic components of vineyards and 5) disseminate results to producers in English and Spanish via field days, presentations, a BMP guide, and social media. The recently published report on Nature based Climate Solutions (NbCS)8 emphasizes the critical need for studies such as these that engage in on-farm research investigating the stacking of sustainable farming practices, while considering the inherent variability of landscapes, soils, resource availability and production goals. Our network of commercial vineyards will consist of vineyards with medium to long term grazing legacies (+3 years minimum) to vineyards with no history of grazing. This diverse network will facilitate the collection of real-world information on management strategies, input use, soil health and crop yield outcomes as a function of edaphoclimatic conditions underlying potential benefits and tradeoffs 8. By providing empirical assessments of integrated systems across the three pillars of sustainability, we hope to improve the profitability and natural resource base of vineyards and grazing operations, while increasing the quality of life in farming communities.

Project Objectives:

Research Objectives

Obj. 1: Establish a participatory research network across California comprised of 45 commercial vineyards with current management legacies along a grazing gradient: Non-Grazed (NG), Integrated Sheep Vineyard Systems (ISVS) with Winter Grazing (ISVS_WG) and extended Winter and Summer Grazing (ISVS_WSG) (n = 15 per treatment over the 3-yr study).

Obj. 2: Measure the impacts of grazing intensities and co-management practices on vineyard soil health, species biodiversity, vine health/nutrition, yield, berry quality, and input and labor use.

Obj. 3: Determine the economic performance of ISVS and conventional viticulture systems.

Obj. 4:  Integrate socio ecological and economic outcomes to identify the benefits and tradeoffs of grazing vineyard understories and inform the development of best management practices.

Outreach Objectives

Obj. 1: Create a Best Management Practice (BMP) guide in English and Spanish synthesizing grower knowledge and research results.

Obj 2: Generate a cost-return planning tool to assist producers seeking to integrate grazing into their operations. 

Obj. 3: Share project results and best management practice guidelines to a minimum of 150 producers via 3 in-person on-farm field days and 3 workshops. The effects of ISVS on soil health, biodiversity, yield and grape quality and cost and expected returns will be presented.  The benefits of sheep for meat and fiber markets, as well as ecosystems benefits, such as fire load management will be included.

Obj. 4:  Disseminate research results, field day demonstrations, workshops, our BMP guide, and the cost-return tool to an extended audience using podcast interviews, industry publications, Facebook live streams, twitter, and other social media outlets handled by the team’s outreach specialists.

Obj. 5: Produce 3 academic journal articles and present findings at local and national conferences.

Cooperators

Click linked name(s) to expand/collapse or show everyone's info
  • Sophia Bates - Producer
  • Rebecca Burgess
  • Tommy Fenster
  • Jaime Irwin - Producer
  • Kelly Mulville - Producer
  • Lucas Patzek
  • Clay Shannon - Producer
  • Sara Tiffany
  • Maria Zumkeller - Producer

Research

Materials and methods:

Obj. 1: Monitoring will be conducted on triads of commercial vineyards across a management gradient. The geographic region will span three main regions of California: North (Mendocino, Lake, Sonoma, Napa)  Central Valley(San Joaquin and Solano), and Central Coast (San Benito County). These three regions also align with the field day locations outlined in the outreach section.  A total of 45 vineyards (n = 15 per treatment) that represent the three management systems (NG, ISVS_WG, ISVS_WSG) with at least 3 years of management legacy will be identified and strategically selected to fall along a regenerative-conventional co-management gradient9. The gradient is from Fenster et al.  (2021) and it utilizes rankings derived from a character matrix of nine different practices that were considered as regenerative or conventional (Table 1). Engaging in a regenerative practice or abstaining from a conventional practice resulted in the vineyard getting a score of 1 for that matrix category. Utilizing a conventional practice or abstaining from a regenerative practice entail the vineyards receiving a score of 0 for that matrix category. Hence, the maximum regenerative score a vineyard could receive is 9 and the lowest is 0. Table 1 displays where each vineyard falls along this gradient and the management practices contributing to this score. 

 Each triad will be within 20 miles of each other, on a similar soil type, the same rootstock and variety, and under the same management practices except for the grazing treatment. Vineyards will be sampled for one field season at three key phenological stages (bud break, 50% veraison, and harvest). Data was collected from 15 vineyards in 2022 and a new set of 15 vineyards in 2023 during budbreak, veraison, and harvest in 2022 spanning all metrics described in objectives 2 and 3. Figure 1 displays a map of the 30 vineyards sampled to date. Another new set of 15 vineyards will be sampled in 2024, allowing for 2025 to be devoted to analyzing/disseminating results and the completion of outreach activities. 

Obj. 2: Four, 50-meter transects at least 20m apart (Figure 2) will be established in each vineyard. Vines and forage development and composition will be monitored throughout the growing season. We will also quantify soil health metrics and species biodiversity (plant, invertebrate and vertebrate). Leaf petiole nutrient profiles will be determined just prior to 50% veraison and yields and berry quality at harvest. We will use general linear mixed-effect models, general additive models, and multivariate analyses such as Principal Component Analysis, K clustering and normalized indexes to explore the relationship between grazing and different combinations of management practices on systems outcomes. Input use will be recorded for each vineyard as part of the grower intake survey described in Obj 3 and results will be analyzed considering input levels to determine shifts in productivity (output per unit of input).

0-60cm soil metrics (budbreak sampling trip, Regen Ag Labs; Pleasanton, NE): pH, total soil carbon (TSC), soil organic carbon (SOC), mineral associated organic carbon (MAOC), particulate organic carbon (POC), total soil nitrogen(TSN), NO3-N, PO4-P, S, K, Ca, Mg, Na, Cation Exchange Capacity (CEC), Base Saturation percentage, H % saturation, Ca % saturation, Mg % saturation, Na % saturation, Gravimetric soil moisture percentage, and available water holding capacity (AWHC).

Four 0-60cm soil cores will be taken in each transect at the 0m (Aisle), 15m (Margin), 30m (Row), and 45m (Aisle) marks (Figure 3). In the field the cores will be cut into 0-5cm, 5-10cm, 10-15cm,15-30cm, and 30-60cm increments. The soil for each depth zone will be composited at the transect level (4 transects/vineyards). Soils will be analyzed at Regen Ag Labs for the above analyses where they will be carried out via standard lab procedures. Soil carbon and nitrogen stocks on a per hectare basis will be determined via dry combustion and elemental analysis combined with the equivalent soil mass protocol24.

Following the completion of the above analyses, Regen Ag Labs will return the remaining soil to the Gaudin Lab at UC Davis for measurement Mineral Associated Organic Carbon and Particulate Organic Carbon by dispersion via the Par + Den5 methodology outlined in Poeplau et al 25.

Soil classification and bulk density (Budbreak sampling trip). Soil classification and surface bulk density (BD) samples will be collected at the 25 m point of each transect, following the protocol outlined by the NRCS26. These soil samples will then be analyzed for their sand, silt, and clay percentages using the hydrometer technique27.

Water infiltration rates (Budbreak sampling trip). Water infiltration rates will be measured at the 25m mark of each transect, following the NRCS protocol, where 444 mL of water will be poured into a sheet-metal ring (15.2 cm diam, 13.5 cm tall) hammered 6.5 cm into the soil28.

Unsaturated hydraulic conductivity (Budbreak sampling trip). The mini disk infiltrometer (Meter Group- Pullman, WA) will be used to calculate unsaturated hydraulic conductivity at the 25m mark of each transect.

Soil microbial community and Haney soil health metrics (Budbreak sampling trip). In each transect twelve 0-15cm soil cores will be taken every 4 m (4-48m), following an aisle, margin, row sampling pattern (Figure 3). The samples will be composited at the transect levels and placed in coolers before being shipped to Regen Ag Labs for analysis of Phospholipid fatty acid profiles29 to determine microbial diversity, abundance of major microbial groups and biomass and Fungus and bacteria.

Water extractable organic C and total N (WEOC and WEON) (Teledyne-Tekmar Torch C:N analyzer), mineralizable C (IRGA-Li-Cor 840A, LI-COR Biosciences, Lincoln NE), and soil nutrient levels using H3A extracts (organic root exudates, lithium citrate, and two synthetic chelators-DTPA, EDTA) 30 will be determined.

Plant community (budbreak and veraison sampling trips). Percent ground cover and composition in each of the transects will be recorded during the budbreak and veraison sampling trips. Understory biomass will be assessed during the budbreak sampling trip using quadrats (0.1 m2) placed at the 0m (aisle), 25m (margin), and 50m (row) marks of each transect. At these marks the Canopeo app will be used to determine the percent green cover in the quadrat. A visual scaled assessment will be conducted to assess total ground cover in the quadrat. Species richness and functional diversity of the plants in the quadrat will be recorded (grasses, forbs, forb brassicas, forb legume, native, non-native, major agronomic weed). Every 5m a falling plate meter (0.1m2) will be used to estimate biomass31. At the 25m mark of each transect, the vegetation will be severed at the soil line and bagged. Vegetation will be dried and weighed to calibrate the falling plate meter and estimate biomass at each vineyard31. Vegetation will then be sent to Regen Ag Labs for a standard feed/forage analysis (forage quality, dry matter, and protein content).

Invertebrate community (budbreak and veraison sampling trips). The epigeal invertebrate communities will be sampled during the budbreak sampling trip using a 15 cm tall 0.25 m2 sheet metal quadrat6,12,32. The invertebrate communities will be collected from the soil surface and top 2 cm of the soil with mouth-operated aspirators over 15 min and will be preserved in 70% ethanol.

The understory invertebrate community will be sampled using sweeps during the bud break and veraison sampling trips.  25 sweeps will be performed along a path which parallels the 25m mark of each transect.

The vineyard canopy invertebrate community will be sampled using yellow sticky traps during the veraison sampling trip. A yellow sticky trap will be hung on each of the 12 flagged vines (3 per transect). The yellow sticky traps will be collected during the harvest sampling trip approximately 3 weeks later. Thus sampling methodology will focus on the leafhopper pests and the their associated parasitic wasps

The biomass of the invertebrates per 0.25 m2 will be weighed to the nearest 0.0001 g. Invertebrates will be identified to the morphospecies level and placed into functional groups. Voucher specimens are all housed in the Mark F. Longfellow Biological Collection at Blue Dasher Farm, Estelline, SD, USA.

Avian community (budbreak sampling trip). The avian community in each vineyard will be assessed (abundance, species diversity, functional diversity) during the morning hours in each vineyard at budbreak. An Ecdysis ornithologist will walk the vineyard, recording the time spent walking the vineyard (~ 1 hour) as well as the distance walked (~1 mile). The number of birds and the bird species will be counted via visual and auditory identification.

Petiole nutrients (veraison sampling trip). 100 Petioles will be sampled from each transect just prior to 50% veraison from recently matured leaves opposite clusters. The petioles will be placed in paper bags, dried, and sent to Regen Ag Labs for: NO3-N, Total -N, P, K, Zn, Mn, Na, B, Ca, Mg, Fe, Cu.

Yield and grape quality sampling (harvest sampling trip).

In each transect the vines at the 15m, 30m, and 45m transect marks will be sampled for yield, equating to 12 vines per vineyard. Clusters will be clipped, counted, and weighed in the field.

Across each transect 300 berries will be sampled on ~ 115 vines. The berries will be placed in a cooler in the field. ½ of the berries will be stored at 2 C and processed within 72 hours for primary chemistry quality analysis. The other ½ of the berries will be stored at -20 C until secondary quality analysis. The samples will be weighed to determine mean berry weight. The following primary chemistry analyses will be performed: brix, total titratable acidity, pH, yeast assimilable nitrogen. The following secondary chemistry analyses will be performed total phenolics, total anthocyanins, and Carbon 13 isotope analysis (water use efficiency).

Obj. 3: We will conduct a Cost and Return Study of an ISVS, similar to the 2016 Biodynamic Farm Standard Cost and Returns Study. This will provide an accurate and up to date assessment of the total costs (operating and overhead costs) associated with ISVS. We will then use Net Present Value (NPV) to calculate how ISVS compares in profitability to conventionally managed vineyards over the useful life of the vineyard. The Cost and Returns Study and NPV analyses will be based on data collected from the growers in the study via a survey detailing management practices and input use. Numerous costs and returns studies are already available at UC Davis for conventional viticulture systems33. Since no tool currently exists for integrated systems, we will develop a new spreadsheet tool which incorporates operating costs, overhead costs, and revenues associated with integrating sheep.

Obj. 4: This systems-level approach will allow us to quantify the interactions occurring among the chemical, physical, biological, and economic components of vineyard systems. We hypothesize that the integration of grazers will result in reduced mechanical and chemical disturbances and an enhanced resource base. This will lead to stronger linkages among the biological communities and soil health metrics, revealing a significant relationship between enhanced biodiversity and the delivery of ecosystem services, such as pest control34,35, soil fertility 6,36and input use. Hierarchical and K means clustering, co-occurrence networks and Principal Component Analysis will be used to assess these relationships. Further, because the vineyards in the study will have been in their established systems from a minimum of three years to as many as 25 years, the study will explore the relationship between time under management to the ecological and environmental metrics collected6.

A map showing the vineyards sampled in 2022 and 2023.
Figure 1. Map of the 30 vineyards comprising the 2022 and 2023 study years. An additional 15 vineyards with a focus on Napa/Sonoma will be sampled in 2024.
The image shows the four 50m transects in one of the vineyards
Figure 2. Transect placement in a trellised vineyard. Each red line represents a transect.
The picture shows the zones along which soil and plant community sampling occurs in each vineyard. These zones are the vine row, margin, and tractor row.
Figure 3. The highlighted regions in the left of the photo represent the sampling regions within vineyards. The right is left uncolored for a visual reference of what will be found in the field. Picture taken by Paige Green.

Research results and discussion:

At this time there is still one more field season to complete and all results and observations reported are preliminary. While we expect the general trends to be reinforced with an additional year of data it is possible that the final findings may not align with what is reported here.

From observing the preliminary data presented in Figures 4 and 5 there seems to be a statistically significant trend towards grazing and regenerative management being associated with enhancing soil health and biodiversity metrics.  It is important to note that both figures 4 and 5 are visualizations that do not account for key covariates such as soil texture and latitude/longitude. When these covariates are included in the general additive models (GAM) the differences observed are enhanced. Additionally, in these GAM models grazing generally performs better than a vineyard's regenerative-conventional designation in predicting sustainability outcomes, suggest that well managed prescribed grazing may be a keystone management practice.

Regarding nitrogen (N), the vineyards with grazing have significantly greater amounts of total N. Grazing and non-grazing vineyards have similar amounts of inorganic N, but grazing vineyards have significantly more organic N. Of this organic N the grazing vineyards have significantly more water extractable organic nitrogen (WEON), which is the pool of readily mineralizable N.  While grazing vineyards have increased levels of C and N, both grazing and non- grazing vineyards have similar ratios of  SOC:TSN (11:1) as well as WEOC:WEON (12:1), suggesting that N is not immobilized in either system. This is synthesized by the higher Haney soil health scores observed in Figure 4. 

From observing table 1, one will notice that vineyards integrating grazing as well as forming regenerative systems are a mix of certified organic and conventional farms. Further, both grazing and regenerative management perform better in predicting sustainability outcomes than whether a vineyard is organic certified. Table 2 highlights that vineyards with grazing and those without utilize organic amendments and tillage similarly, with the grazing vineyards utilizing less synthetic inputs and following grazing best practices of minimizing bare soil. Table 3 displays the variables the study is aiming to control for, with the results suggesting the study is doing a good job in controlling for these variables. Overall, these results suggest that both organic and conventional vineyard systems could enhance their sustainability outcomes by integrating grazing and potentially stacking other sustainability practices.

Regarding grazing intensities, one of our research goals is to determine if increasing the number of prescribed grazing events (adding post-bud break grazing events-ISVS_WSG) over the course of growing year has a negative, positive, or neutral effect on soil health metrics and the delivery of associated ecosystem services.  We are still in the process of documenting stocking rates, number of days of grazing, and rest periods so we are not ready to fully present this data.  However, in table 4. for we do present some basic data on the ground cover composition of the non grazing vineyards, ISVS_WG and ISVS_WSG vineyards. Table 4  suggests that the grazing being utilized in the vineyards aligns with prescribed grazing best practices, with grazing increasing the total ground cover and total green/living ground cover at budbreak. Additionally, both grazing treatments have greater total cover at 50% veraison than the non-grazing vineyards suggesting that grazed vineyards are minimizing the amount of bare soil and aligning with prescribed grazing best practices. Regarding the green cover present at 50% veraison there is no difference among the treatments, suggesting that while grazing is associated with increased residue/ground cover that protects the soil it does not lead to increased vineyard floor green cover later in the growing season, which could increase transpiration and reduce water available to the vines. 

We hypothesize that there will not be a significant relationship between an increase in vineyard grazing events and a decline in soil health metrics. In semi-arid Mediterranean climates grazing when not carried out at the optimum intensity (ideal stocking rate, duration, and rest periods) can result in significant soil degradation. Currently the most common grazing regime in vineyards is to utilize 1-2 prescribed rotational grazes (high stocking rate, short duration event) during the winter dormant season. However, in CA vineyards the understory plant community puts on its most significant biomass gains post-budbreak and into fruiting when the available moisture, combined with the longer/warmer days accelerates growth. Therefore, we hypothesize that additional grazing events during the spring/summer would still align with prescribed grazing best practices and not constitute overgrazing. Additionally, the alternative to grazing is increased tractor passes resulting in tillage, mowing, or herbicide usage. Hence, when compared to the baseline of vineyard understory management we hypothesize that grazing still results in an overall reduction in the intensity of disturbances taking place on the vineyard floor.

From observing the preliminary data presented in Figure 6 there generally seems to be no relationship between grazing and regenerative management being associated with enhancing yield or basic berry quality metrics. However, we still need to perform the total phenolic, anthocyanin and C 13 isotope analyses on the berries. While there is substantial overlap in CIs between yield in regenerative and conventional vineyards there does appear to be a slight trend  (not statistically significant) towards lower yields in the regenerative systems. Additionally, based on the survey results to date it appears that grazing is associated with reductions in inputs (table 2). It appears that vineyards that integrate grazers and stack sustainable practices can enhance their sustainability outcomes without seeing a drop in production metrics.

 

 

Spider plots summarizing soil health and biodiversity metrics. On the left is a plot which compares vineyards integrating sheep grazing to vineyards without grazing. On the right is a spider plot comparing vineyards under regenerative and conventional management.
Figure 4. Preliminary results (2022 and 2023 data) for a selection of soil health, plant community, and epigeal invertebrate metrics. Soil health score refers to the Haney Soil Health Score.  Covariates, such as soil texture, latitude/longitude, and grazing intensity are not included in this visualization. The means were normalized and scaled using the Scale function in base R. The shaded areas represent the 95% confidence intervals. On the left is a comparison of non-grazed (NG) and Grazed (G) vineyards that integrated sheep either during the winter dormant season or during the winter and summer grazing seasons. On the right is a comparison of vineyards designated as either conventional or regenerative (5 or more sustainable practices) as defined by Fenster et al. (2021).
Principle Component Analysis (2022 and 2023 data) for a selection of soil health (SOC, TSN, Haney soil health score, mineralizable carbon, microbial biomass) plant community (mean plant species richness from budbreak and veraison sampling), and epigeal invertebrate metrics (species richness and abundance from budbreak sampling.
Figure 5. Principle Component Analysis (2022 and 2023 data) for a selection of soil health (SOC, TSN, Haney soil health score, mineralizable carbon, microbial biomass) plant community (mean plant species richness from budbreak and veraison sampling), and epigeal invertebrate metrics (species richness and abundance from budbreak sampling). Covariates, such as soil texture, latitude/longitude, and grazing intensity are not included in this visualization. The means were normalized and scaled using the Scale function in base R. On the left is the PCA visualizing the vineyards with and without grazers and where they fall along the conventional-regenerative gradient. Red indicates vineyards the integrated sheep and blue represents vineyards with not sheep. The size of the dots corresponds to the vineyards’ regenerative score, with zero being the lowest score and 9 being the highest score6,7. On the right is the PCA with biplot visualizing the loadings of soil health, plant and epigeal invertebrate community metrics.
Spider plots displaying Preliminary results (2022 and 2023 data) for a selection of yield, berry quality, and vine fertility metrics.
Figure 6. Preliminary results (2022 and 2023 data) for a selection of yield, berry quality, and vine fertility metrics. The means were normalized and scaled using the Scale function in base R. The shaded areas represent the 95% confidence intervals. On the left is a comparison of non-grazed (NG) and Grazed (G) vineyards that integrated sheep either during the winter dormant season or during the winter and summer grazing seasons. On the right is a comparison of vineyards designated as either conventional or regenerative (5 or more sustainable practices) as defined by Fenster et al. (2021).
Table summarizing management on each of the vineyards in the study.
Table 1. Regenerative practices are scored as 1, and conventional as 0. Farms that score 5 or higher are considered regenerative. Farms that score below 5 are designated conventional. The bold numbers indicate each farm’s overall regenerative score. This scoring matrix is from Fenster et al. (2021) and Fenster, Oikawa, Lundgren. (2021).
Table displaying the mean regen-conv matrix scores as the percentage of Grazing and Non-grazing vineyards integrating that practice.
Table 2. Table displaying the mean regen-conv matrix scores as the percentage of Grazing and Non-grazing vineyards integrating that practice.
Table displaying variables the study is aiming to control for.
Table 3. Table displaying variables the study is aiming to control for.
Table showing differences in ground cover between grazing and non grazing vineyards. Show that grazing vineyards have more green cover and total ground cover at budbreak
Table 4. The table shows the differences in ground cover among the vineyards not grazing, those just grazing prior to budbreak , and those the graze prior to budbreak as well as after budbreak.

Participation Summary
16 Producers participating in research

Research Outcomes

Recommendations for sustainable agricultural production and future research:

Regarding research outcomes we still have the third and final season of fieldwork. Additionally, while we have done some statistical analyses and data visualizations we still need to perform more in depth analyses on the full data set.   At this time all data, insights, and recommendations are preliminary.  

In this research we have made an explicit effort to work with vineyards and graziers that follow prescribed grazing best practices as outlined by the NRCS. At this time it appears that vineyards can support prescribed grazing prior to budbreak as well as during the growing season. However, if vineyards do not utilize prescribed grazing best practices, resulting in over or under grazing it would seem likely that the benefits observed to date would not translate. Therefore, it is imperative that vineyards integrating grazing work with graziers to ensure the grazing regimes are following the optimum stocking rates, grazing duration, and necessary rest periods. As these can change year to year based on weather, cover crop composition etc., it is necessary for vineyard managers and graziers to work together to adapt the grazing management to the present conditions. Vineyards with high-wire trellising systems present the most immediate opportunity for increasing grazing events and have the opportunity to also ease management logistics for graziers (i.e. there may still be sufficient cover crop/forage, but bud break starts and all the sheep must go). 

Overall, it appears that vineyards that integrate prescribed grazing and stack sustainable practice can enhance their sustainability outcomes without seeing a drop in production metrics. Vineyards that integrate grazers appear to be reducing the number of tractor passes (~2-3 per growing season) they utilize for managing ground cover, while reducing their synthetic and fertilizer and herbicide usage, with organic amendments and tillage remaining constant among grazing and non grazing systems. 

Regarding, future research we will have a  better sense of future research needs once this project is closer to completion. 

9 New working collaborations

Education and Outreach

5 Consultations
1 Curricula, factsheets or educational tools
1 On-farm demonstrations
4 Published press articles, newsletters
3 Webinars / talks / presentations
3 Workshop field days

Participation Summary:

80 Farmers participated
340 Ag professionals participated
Education and outreach methods and analyses:

Education Plan

Our outreach goals are to create Best Management Practices (BMP) guidelines for growers and sheep operators while implementing a multipronged outreach plan to share results on feasible and innovative sheep grazing practices. Additionally, by highlighting the role of sheep in regenerative systems we hope to help expand the market for CA sheep-based products (meat and fiber). The outreach objectives are designed to reach English and Spanish speakers. The team members have extensive experience producing meaningful and effective outreach alongside their research. The target audience for all the outreach activities will be viticulturists and sheep operations, with the secondary audience consisting of farmers in other perennial cropping systems, those involved with the winemaking industry, and consumers of wine and sheep-based products. The timeline for achieving these outreach objectives can be found in the associated Gantt chat.  Our specific objectives are listed below. In the bullet points below each objective we state where we are in accomplishing this objective. 

Obj. 1: Create a Best Management Practice (BMP) guide in English and Spanish synthesizing grower knowledge and research results.

  • The research to inform the BMP is 2/3 complete and will be finished by 2025. However, the BMP will mostly be based on interviews with vineyard managers/owners and livestock operators. Interviews for the BMP will be led by CAFF and will begin this summer. 

Obj 2: Generate a cost-return planning tool as part of the cost-return study to assist producers seeking to integrate grazing into their operations. 

  • To date we have sent out management surveys related to each of the 30 vineyards in the study. We have received responses for 21 of the 30 vineyards. At the end of the 2024 growing season surveys will be sent out to the 2024 vineyards. 
  • In addition to surveys the development of the cost-return study/planning tool will also depend on more in-depth interviews with growers. Dr. Brittney Goodrich is leading these interviews and is coordinating with CAFF who are also conducting interviews for a BMP guide. Interviews will commence this summer.

Obj. 3: Share project results and best management practice guidelines to a minimum of 150 producers via 3 in-person on-farm field days and 3 workshops. The effects of ISVS on soil health, biodiversity, yield and grape quality and cost and expected returns will be presented.  The benefits of sheep for meat and fiber markets, as well as ecosystems benefits, such as fire load management will be included.

  • Field Days
      • BIFS: Cover Cropping and Livestock Grazing for Regenerative Viticulture
        • 12/5/2023
        • Lodi, CA 
        • Attendees: 65
        • Survey responses: 48
        • This was a field day and also an on-farm demonstration, since it took place in the vineyards block where sheep were grazing to take advantage of the post-harvest residue
        • Link to news article about the field day
  • Workshops
    • Wild Farm Alliance Field Day at Paicines Ranch
      • Presentation on integrating livestock into vineyards and other perennial cropping systems
      • 6/1/2023
      • Paicines, CA
      • Attendees: 60
    • Napa Green Grazing in Vineyards Workshop
      • Presentation on potential ecosystem services of integrating sheep into vineyard systems
      • 2/27/2024
      • Calistoga, CA
      • Attendees: 45
      • News article on workshop
  • Data reports for growers
    • Data reports summarizing the results for each vineyard that was sampled are shared with each grower at the end of the growing season.

Obj. 4:  Disseminate research results, field day demonstrations, workshops, our BMP guide, and the cost-return tool to an extended audience using podcast interviews, industry publications, Facebook live streams, twitter, and other social media outlets handled by the team’s outreach specialists.

Obj. 5: Produce 3 academic journal articles and present findings at local and national conferences.

  • 30 of 45 vineyards have been sampled. The final 15 vineyards will be sampled in 2024. Preliminary data analyses has begun. Materials and method sections have been written. Goal is to begin submitting articles for publication in 2025 and present the final findings at the 2025 Ecological Society of America Conference. 
  • Preliminary findings have been presented at the following conferences
    • ASA, CSSA, SSSA  International Annual Meeting
      • 10/30/2023
      • St. Louis, Missouri
      • Attendees: 50
    • Unified Wine and Grape Symposium
      • 1/24/2024
      • Sacramento, CA
      • Attendees: 100
    • CA Plant and Soil Conference
      • 2/6/2024
      • Fresno, CA
      • Attendees: 100

Gantt_Chart_ISVS_2022_Full_Proposal

Education and outreach results:

Obj. 1: Create a Best Management Practice (BMP) guide in English and Spanish synthesizing grower knowledge and research results.

  • Just beginning theses efforts. Will have an update in the next report.

Obj 2: Generate a cost-return planning tool to assist producers seeking to integrate grazing into their operations. 

  • We are still getting survey results back and need to conduct follow up interviews. Preliminary findings indicated that grazing is reducing 2-3 tractor passes associated with mowing/herbicide usage. Preliminary results also suggest that grazing operations are utilizing less synthetic fertilizers and herbicides. 

Obj. 3: Share project results and best management practice guidelines to a minimum of 150 producers via 3 in-person on-farm field days and 3 workshops. The effects of ISVS on soil health, biodiversity, yield and grape quality and cost and expected returns will be presented.  The benefits of sheep for meat and fiber markets, as well as ecosystems benefits, such as fire load management will be included.

Obj. 4:  Disseminate research results, field day demonstrations, workshops, our BMP guide, and the cost-return tool to an extended audience using podcast interviews, industry publications, Facebook live streams, twitter, and other social media outlets handled by the team’s outreach specialists.

  • To date 170 people have been engaged via in-person outreach events (1 field day and 2 workshops).
  • CAFF shared 1 Instagram post to promote the 12/5/2023 field day, receiving 103 likes. 

Obj. 5: Produce 3 academic journal articles and present findings at local and national conferences.

  • To date preliminary findings have been presented at 3 conferences, reaching 250 people at those conferences
9 Farmers intend/plan to change their practice(s)
1 Farmers changed or adopted a practice

Education and Outreach Outcomes

Recommendations for education and outreach:

At this stage we are still at the beginning stages of our outreach and education efforts. To date we have put on one field day and have presented at two workshops. At the two workshop we were guest presenters and not the organizers, so we did not collect surveys.  However, at all of these events we have had multiple conversations with growers, answering their questions, exchanging contact information, and establishing relationships. Qualitatively, it seems that in-person events are invaluable for furthering adoption of sustainable agricultural practices. 

Regarding future efforts we are excited about the development of the BMP guide in English and Spanish, as well as the cost return study/planning tool. Both, of these materials will be informed by our research, but they will also be formed by interviews with growers and graziers. The results will be a synthesis of quantifiable and qualitative metrics, as well as grower insights that are not typically captured in journal articles. While, we are excited to publish journal articles it seems that it is critical for applied agricultural research to also produce information/tools that are accessible and practical to growers. 

20 Producers reported gaining knowledge, attitude, skills and/or awareness as a result of the project
Non-producer stakeholders reported changes in knowledge, attitudes, skills and/or awareness as a result of project outreach
11 General public
17 Ag Service Providers
Key areas taught:
  • Implementing grazing in vineyards
  • Benefits of integrating grazing in vineyards
  • Costs and equipment associated with integrating grazing in vineyards
  • Financial and funding opportunities for integrating grazing in vineyards
Key changes:
  • Implementing grazing in vineyards

  • Benefits of integrating grazing in vineyards

  • Costs and equipment associated with integrating grazing in vineyards

  • Financial and funding opportunities for integrating grazing in vineyards

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.