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
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 8 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, a new set of 15 vineyards in 2023, and a new set of 19 vineyards in 2024 during budbreak, veraison, and harvest spanning all metrics described in objectives 2 and 3. Figure 1 displays a map of the 49 vineyard blocks sampled to over the course of the study. 2025 is 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 of the 49 vineyard blocks sampled over the course of the study (2022-2024).
Figure 1. A map of the 49 vineyard blocks sampled over the course of the study (2022-2024).
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:

Field work for this project was completed in October of 2024. The vast majority of the lab analyses have been completed. All that remains are identifying insects on the last three sticky trap samples from 2024 and sending the grape pulps to the UC Davis isotope lab (prep work completed) to determine delta C 13  to assess water use efficiency. While data analysis has begun we are are still in the exploratory phase, and all results and observations reported should still be considered preliminary as we have not yet submitted for publication. 

From observing the preliminary data presented in Figures 4 and 5 there was 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 were included in the general additive models (GAM) the differences observed were enhanced. In the GAMs analyzing the effect  the individual management practices comprising the regenerative matrix had on sustainability outcomes, grazing consistently appeared as one of the most significant management practices.  Additionally, in some of these GAM models grazing performed better than a vineyard's regenerative-conventional designation  in predicting sustainability outcomes. For other metric's a vineyard's regenerative designation served as a better predictor. These analyses suggest that grazing is a keystone management practice for improving soil C and N dynamics, microbial biomass, as well as other biodiversity variables. Simultaneously, these analyses highlight the importance of stacking sustainable practices to create regenerative vineyard systems.  

Regarding soil organic carbon and (SOC) and total soil nitrogen (TSN), the vineyards with grazing had significantly greater amounts of SOC and total TSN. Years under grazing was significantly and positively associated with yearly SOC accrual. However, years under regenerative management was a significantly better predictor variable with each year under regenerative management resulting in 0.28 Mg/SOC/ha/yr  (p=0.002). With TSN years under grazing was the best predictor, significantly correlating with  total N accrual at a rate of 27 lbs./TSN/acre/year (p= 0.004). Grazing and non-grazing vineyards had similar amounts of inorganic N, but grazing vineyards have significantly more organic N. Of this organic N the grazing vineyards had significantly more water extractable organic nitrogen (WEON), which is the pool of readily mineralizable N.  While grazing vineyards had increased levels of C and N, both grazing and non- grazing vineyards had similar ratios of  SOC:TSN (11:1) as well as WEOC:WEON (12:1), suggesting that N was 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. Table 2 highlights that vineyards with grazing trended towards less usage of organic amendments and tractor row tillage, with the grazing vineyards utilizing less synthetic inputs, particularly herbicides and fertilizers, while following grazing best practices of minimizing bare soil.  Further, table 2 suggests that dormant + growing season grazing (ISVS_WSG) can play a key role in further reducing synthetic herbicides, tractor row tillage, and the need to bring in offsite organic amendments. 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.

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.  In table 4. we  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 aligned with prescribed grazing best practices, with grazing increasing the total ground cover and total green/living ground cover at budbreak. Additionally, both grazing treatments had greater total cover at 50% veraison than the non-grazing vineyards suggesting that grazed vineyards were minimizing the amount of bare soil and aligning with prescribed grazing best practices. Regarding the green cover present at 50% veraison there was no difference among the treatments, suggesting that while grazing was associated with increased residue/ground cover that protects the soil it did not lead to increased vineyard floor green cover later in the growing season, which could increase transpiration and reduce water available to the vines. Further, the GAMs run to date suggested no differences in soil health metrics between vineyards utilizing ISVS_WG or ISVS_WSG, with grazing in general outperforming non-grazing sites. 

From observing the preliminary data presented in Figure 5 there appeared to be no relationship between grazing and regenerative management being associated with enhanced yield or basic berry quality metrics.  However, we still need to analyze the berry phenolic data. The slight overlap in CIs between yield in regenerative and conventional vineyards initially suggested a trend  towards lower yields in the regenerative systems. However, there was no difference in yield between regenerative and conventional systems when accounting for wine growing regions in the model. With the study primarily designed to focus on grazing, the vineyards in the Lodi/Delta region (San Joaquin and Solano counties) all fell under the conventional or transition designation. These vineyards all follow high yield production models, skewing the yield results for vineyards designated conventional by the regenerative-conventional scoring matrix.  

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 without seeing a drop in yield and berry quality metrics.

Figure 4. Preliminary results 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, regenerative (4 or more sustainable practices), or transition to regenerative (< 3 years) as defined by Fenster et al. (2021).
Figure 4. Preliminary results 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, regenerative (4 or more sustainable practices), or transition to regenerative (< 3 years) as defined by Fenster et al. (2021).
Figure 5. Preliminary results 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, regenerative (4 or more sustainable practices), or transition to regenerative (< 3 years) as defined by Fenster et al. (2021).
Figure 5. Preliminary results 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, regenerative (4 or more sustainable practices), or transition to regenerative (< 3 years) as defined by Fenster et al. (2021).
Table 1. Regenerative practices are scored as 1, and conventional as 0. Farms that score 4 or higher are considered regenerative. Farms that score below 4 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 1. Regenerative practices are scored as 1, and conventional as 0. Farms that score 4 or higher are considered regenerative. Farms that score below 4 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 2. Table displaying the mean regen-conv matrix scores as the percentage of Grazing and Non-grazing vineyards integrating that practice. Variability as 95% CI’s.
Table 2. Table displaying the percentage of Grazing (dormant and dormant +growing season) and Non-grazing vineyards integrating that practice. Variability as 95% CI’s.
Table displaying variables the study is aiming to control for.
Table 3. Table displaying variables the study is aiming to control for.
Table 3. Table displaying ground cover at budbreak in 50% veraison in vineyards with no grazing, dormant grazing and dormant + growing season grazing.
Table 4. Table displaying ground cover at budbreak and 50% veraison in vineyards with no grazing, dormant grazing (ISVS_WG) and dormant + growing season grazing (ISVS_WSG).

 

Participation Summary
26 Producers participating in research

Research Outcomes

Recommendations for sustainable agricultural production and future research:

Regarding research outcomes we have completed field work and are wrapping up the final lab analyses. Additionally, while we have begun 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. 

Regarding, future research we will have a  better sense of future research needs once we finish analyzing the data. 

15 New working collaborations

Education and Outreach

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

Participation Summary:

200 Farmers participated
500 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  complete and will be finished by July 2025. Interviews were completed last summer. Our team just completed first draft and solicited feedback from stakeholders. The team is now working to incorporate stakeholder feedback. At this point the team has created a 1 pager that summarizes the BMP findings. Attached below. 
  • ISVS one pager

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 49 vineyards in the study. We have received responses for 43 of the 49 vineyards. 
  • In addition to surveys the development of the cost-return study/planning tool will also depend on more in-depth interviews with growers. These interviews have been completed and we expect this cost-return study and planning tool to be completed by this Fall. 

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
      • Napa Grazing in Vineyards Field Day at Honig Vineyard and Winery
        • 3/7/2025
        • Napa, CA
        • Attendees: 20
        • Survey responses:7
        • Napa grazing in vineyards flyer.
          Napa grazing in vineyards flyer
  • 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
    • Cultivating Biodiversity, Soil Health, and Community in North Coast Vineyards
      • Stacking regenerative practices and the importance of grazing for enhancing soil health and biodiversity in vineyards
      • 4/2/2025
      • Medlock Ames Winery, Sonoma, CA
      • Attendees:65
      • Event information
  • 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.

  • 49 of 49 vineyards have been sampled. Data analyses has begun. Materials and method sections have been written. Goal is to begin submitting articles for publication in Summer of 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
    • EcoFarm Conference
      • 1/21-1/24/2025
      • Asilomar, CA
      • Attendees: 75

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.

  • Interviews were completed over the summer of 2024. A first draft has been produced and we just finished receiving stakeholder feedback. Integrating feedback now. 
  • ISVS one pager

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

  • 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, as well as reducing organic amendment usage and tractor row tillage. 

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.

  • We are the lead authors for the book chapter (Integrated crop-livestock systems: enhancing ecosystem services and productive potential) in an upcoming Agroecology text book (The science and practice of agroecology: Pathway to sustainable food systems).  This was just accepted pending minor revisions. This chapter highlights research being conducted as part of this project. 
  • To date preliminary findings have been presented at 4 conferences, reaching 325 people at those conferences
14 Farmers intend/plan to change their practice(s)
2 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 two field days and have presented at three workshops. At the three workshops 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
14 General public
20 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 should not be construed to represent any official USDA or U.S. Government determination or policy.