Final report for GNE21-259
Project Information
The research questions that informed this research are: (1) How do understandings of soil health differ between farmers and Extension professionals? (2) How do understandings of soil health differ by farm type? (3) How do farmers and Extension professionals assess soil health? (4) What factors enable and constrain farmers’ efforts to promote soil health across diverse contexts and approaches to soil health? To answer these questions, I use mental models of soil health to visualize the complex web of social-ecological factors that (1) constitute diverse conceptualizations of soil health, (2) inform modes of assessing soil health, and (3) mediate individuals’ capacity to promote soil health on Vermont farms. Mental models are effective tools for visualizing the factors that inform farmers’ decision-making (Moon et al., 2019; Van Hulst et al., 2020) and have been useful in prior research exploring soil health (Lobry de Bruyn & Andrews 2016; Prager & Curfs 2016).
My findings suggest that conceptualizations of soil health vary by farm type, and that social factors play a significant role in not only how farmers and Extension professionals conceptualize soil health, but also in enabling or constraining collaborative efforts to promote soil health. Co-creating mental models and engaging farmers in participatory analysis of these models proved a valuable way to parse the full social-ecological complexity of soil health. I contend that processes clarifying what individuals understand ‘soil health’ to mean are key for enabling collaboration between diverse actors with diverse types of knowledge and, therefore, may be a valuable strategy for improving soil health outcomes. This research indicates that co-created mental models provide a viable tool for integrating diverse forms of soil health knowledge and supporting collaborations between farmers and Extension professionals.
This research also highlights that soil health is not a singular concept, but a complex, multi-dimensional discourse that encompasses a wide range of meanings, practices, and values. Although the nature of this research precludes broader generalization, my findings indicate that conceptualizations and assessments of soil health vary across farm types. I identified social elements as both central to conceptualizations of soil health and as important mediating factors that enable and constrain efforts to promote soil health. An exclusive focus on how on-farm practices impact the physical, chemical, and biological properties of agricultural soils fails to address the social factors that mediate farmers’ management decisions and attendant soil health outcomes. Agroecological frameworks offer one possible avenue for broadening soil health research to simultaneously consider the social and ecological factors that influence soil management and outcomes. There are many possible benefits to considering soil health research and efforts through the lens of agroecology. First, principles-based frameworks enable multiple pathways for achieving shared goals around soil health. This is important given the diverse agricultural contexts in which farmers make soil management decisions (Montanarella et al., 2016). Second, in explicitly honoring multiple ways of knowing, agroecology provides a framework for integrating diverse types of knowledge to work towards goals shared by diverse actors (Coolsaet, 2016). This is particularly important in the context of soil health, as research indicates that different actors hold different types of knowledge related to soil health (Ingram et al., 2010; Huynh et al., 2020) and may therefore conceptualize or approach soil health in diverse ways (Lobry de Bruyn & Andrews, 2016; Prager & Curfs, 2016; Winstone et al., 2019; Wade et al. 2021; Mann et al., 2021).
To begin to parse complexity and diverse types of knowledge, I advocate for collaborative processes to identify social-ecological principles of soil health. My research indicates that mental models paired with participatory analysis provide powerful tools for visibilizing the connections between social and ecological dimensions of soil health. Principles may effectively expand the soil health research agenda to better reflect diverse discourses of soil health and facilitate knowledge mobilization processes that integrate experiential and scientific knowledge. A principles-based approach also aligns with agroecology.
This research demonstrates that investing in soil health requires investing in farmers and in the social structures that they rely on. This may include things like university extension services, healthcare, and childcare, all of which represent socio-economic factors that may constrain farmers’ capacity to prioritize soil health. Viewing soil health through the lens of agroecology validates the inherent interconnectedness of social and ecological dimensions of soil health. The potential to leverage interest in soil health towards agroecological transitions is an important site for future research.
The objectives of this research are:
- To visualize agricultural service providers’ mental models of soil health
- To visualize farmers’ mental models of soil health
- To identify how soil test results fit into farmers’ soil management strategies
- To visualize farmer mental models of soil health grouped by farm type
- Farm type groups include organic dairy, conventional dairy, organic vegetable & fruit, conventional vegetable & fruit, organic non-dairy animal operations, conventional non-dairy animal operations. These groupings encompass the main agricultural production systems in Vermont. Different production systems entail different soil management strategies, which may influence mental models of soil health.
- To identify whether mental models of soil health differ across farm type
- To compare farmers’ and service providers’ mental models of soil health
- To identify differences in farmers’ and service providers’ understanding and assessment of soil health, which -if unidentified- may impede collaboration in research and outreach related to soil health
- To identify complementary or shared ways of understanding and assessing soil health, which may provide leverage points to further improve collaboration and co-creation of knowledge between farmers and service providers
- To develop clear guidance for extension and other agricultural service providers in the Northeast on how to integrate farmer soil knowledge and collaboratively identify best practices for soil health.
The purpose of this project was to facilitate the integration of farmer and scientific knowledge to improve sustainable soil management and drive effective future research and extension outreach. Co-created mental models of soil health enabled identification of the full suite of social and ecological factors that inform diverse ways of assessing and managing agricultural soil health (see Figure 1).
The Natural Resources Conservation Service defines soil health as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals and humans” (USDA 2019). Restoring and maintaining soil health on farmland remains a pressing issue in the United States (Baumhardt et al. 2015; Nearing et al. 2017). Soil degradation due to agriculture drives climate change (Lal 2012). Simultaneously, degraded soils make farms more susceptible to the adverse impacts of climate change (Moebius-Clune et al. 2016) with attendant consequences for farmer livelihoods (Hatfield et al. 2014).
In the Northeast, recent weather patterns are following past projections of increasing extreme precipitation events and periods of drought (Hatfield et al. 2014, Wolfe et al. 2018). Management strategies that improve and maintain soil health can buffer against the negative impacts of these extreme weather patterns (Moebius-Clune et al. 2016; Magdoff & van Es 2009).
Since the mid-1990s, researchers and scientists have focused on identifying metrics and indicators of soil health (Stewart et al. 2018; Karlen et al. 2019). Much of this work has focused on interpreting soil data and enhancing in-field measurements. While important, this approach fails to acknowledge that soil management decisions are made by farmers in their particular local contexts (Bagnall et al. 2020). Sustainable agriculture requires moving beyond measuring disaggregated indicators and employing integrated, whole-systems approaches to soil management that center farmers’ complex decision-making context (Kibblewhite et al. 2008).
If indicators of soil health are not salient and legible for farmers, they are less likely to adopt practices that promote soil health (Ingram et al. 2016; Reimer et al. 2014). In the context of the Northeast, there is no current published research on how farmers utilize soil test data to inform decision-making and long-term soil management strategies. Not only is it vital to know whether and how farmers use this information, it is also vital to determine whether the metrics and indicators emphasized in traditional soil tests are relevant to farmers in the Northeast. If not, we risk sinking resources into research and outreach tactics that are unlikely to improve agricultural soil health in the region, with attendant consequences for farm viability and the environment.
There is a need to bridge the local knowledge of farmers with scientific knowledge and the expertise of agricultural service providers to identify the information and outreach processes that best support sustainable soil management. Doing so requires the capacity to effectively communicate across different ways of understanding, assessing, and managing soil health. Findings from this research contributed to development of processes for improving collaboration between farmers and agricultural service providers working towards improving and maintaining agricultural soil health.
Cooperators
- (Researcher)
Research
Methodological Background (for all research objectives)
The proposed research used mental models to explore leverage points for further integrating farmer and service provider knowledge systems in the context of Vermont agriculture. By visualizing farmers’ and service providers’ mental models of soil health, this research aimed to improve collaboration for sustainable soil management.
Mental models refer to the cognitive frameworks used by actors to understand or make sense of the world (Jones et al. 2011; for an example, see Figure 2). Cognitive frameworks are constructed and refined through knowledge acquisition processes, past experience, values, beliefs, and assumptions (Carley & Palmquist, 1992; Moon et al. 2019). They are also well-suited to efforts that attempt to identify and analyze the underlying social systems and structures that mediate ecological outcomes (Moon et al. 2019; Jones et al. 2011; van Hulst et al. 2020; Prager & Curfs 2016).
There is no standard way to construct or analyze mental models; rather, appropriate methods for constructing and analyzing mental models are determined by the context and intended applications of the research (Jones et al. 2011). Research design is therefore variable, but often includes common methods for collecting qualitative data, such as interviews, participant observation, document analysis, and focus groups (Jones et al. 2011). This wide array of methods for eliciting and constructing mental models allows for the methodological flexibility necessary to study complex social-ecological systems.
Van Hulst et al. (2020) note, however, that common methods for constructing mental models prioritize expert knowledge over farmer knowledge. This undermines processes of knowledge co-construction and social learning, which have been identified as crucial for effective soil health management strategies (Schneider et al. 2009; Bennett & Cattle 2013). To better enable collaboration between farmers and other stakeholders, Van Hulst et al. (2020) propose an innovative approach to co-constructing mental models. The authors co-constructed mental models with farmers during elicitation interviews using visual displays and concept sorting (see Figure 3). Typically, researchers conducting elicitation interviews produce mental models afterwards based on their own analysis of interview data.
I utilized mixed methods within an iterative process of co-constructing and comparing farmers’ and agricultural service providers’ mental models of soil health. I triangulated across methods to generate mental models that visualize the diverse beliefs, perspectives, experiences, and relationships that inform farmer and agricultural service provider strategies for improving and maintaining soil health. Institutional Review Board (IRB) approval was obtained before research began.
Objectives 1 & 2
I conducted semi-structured interviews to elicit farmers’ and agricultural service providers’ mental models of soil health. I utilized purposive sampling (Tongco 2007) to interview farmers who represent organic and non-organic dairy, vegetable/fruit, and non-dairy animal operations. These farm types employ diverse practices and face unique social and environmental constraints and accordingly, may have different ways of understanding, assessing, and managing soils. I also utilized maximum variation sampling to include participants within each farm group who represent a diversity of farm sizes and farmer identities (Collins 2010). To recruit interviewees, I relied on recommendations from agricultural extension agents, government employees, and key informants within Vermont’s agricultural networks.
Interviews included elicitation questions as well as visual concept sorting, following van Hulst et al. (2020) and their methods for co-constructing mental models. Elicitation questions encouraged participants to discuss the factors, beliefs, and concepts that inform their understanding of soil health. Concept sorting included visually displaying and arranging concepts that emerged during the interview and further exploring how these concepts related to each other qualitatively (see Figure 3). This process allowed the researcher and participant to co-create a mental model of soil health. Van Hulst et al. (2020) note that the “co-constructed mental model method proved to be a useful tool for eliciting individuals’ internal cognitive depictions of the world regarding concepts, practices and beliefs, and their qualitative relationships” (p. 184). Interviews were recorded and transcribed. Due to pandemic restrictions, I conducted interviews virtually and used a shareable digital workspace (Lucidspark) for visual displays and content sorting. After elicitation interviews, I tidied up co-created mental models and shared them back with farmers for final feedback (Figure 1).
Objective 3
I comparatively analyzed farmers’ individual mental models of soil health to identify how farmers’ use soil test results to inform soil management strategies. Methods for this included using data displays and arrays (Creswell & Clark 2007). Data displays and arrays are an analytical method for iteratively comparing across multiple data sources to identify connections and patterns. In this context, I identified similarities and differences in how soil test results fit into farmers’ mental models of soil health.
Objectives 4 & 5
I wanted to know if farmers’ mental models of soil health differ across farm types. This could have implications for tailoring research, outreach, and best management practices related to soil health. To tackle this research objective, I compared and integrated individual mental models to create 7 grouped mental models: 1 for service providers and 6 for the main farm types I identified earlier. The farm type for each individual mental model was recorded during the original elicitation interview, and purposive sampling ensured that all interviews fit into one of the 7 established groups. Hoffman et al. (2014) note that grouped mental models can examine “collective knowledge and understanding of a particular domain held by a specific population of individuals” (p. 13016). Grouping mental models also helped make the findings of this work more broadly relevant.
Again, I triangulated across analytical methods, using visual displays and arrays (Creswell & Clark 2007) as well as comparative qualitative thematic analysis of interview transcripts in NVivo to identify the connections, concepts, practices, barriers, and other factors and themes that emerged as common across the individual mental models within each group. See Figure 4 for an example of the process for combining individual mental models to create grouped mental models.
Once the grouped mental models were completed, I compared the 6 grouped mental models for major farm types. I used similar processes of visual displays and arrays paired with thematic analysis in NVivo to identify similarities and differences across the grouped mental models of soil health by farm types.
Objectives 6-8
To compare farmer and service provider mental models of soil health, I compared the 7 grouped mental models. I used an iterative approach that incorporated my own analysis with participatory analysis. I used a combination of visual displays and arrays combined with thematic analysis using NVivo software. This identified major similarities and differences in mental models of soil health.
Next, I incorporated participatory analysis of grouped mental models. I conducted 7 focus groups: 6 with farmers (grouped by farm type) and 1 with agricultural service providers. All individuals who participated in interviews also participated in focus groups. Within the focus groups, I asked each farmer group to compare their grouped mental model to that of the service providers’. I similarly asked service providers to compare their group’s mental model to farmer groups. Participants were asked to identify what they saw as important differences and similarities across the grouped mental models of soil health. In addition, participants were asked to discuss why they think similarities or differences exist, whether communication of knowledge across farmer and service providers is effective, and what might improve integration of farmer and service provider knowledge. Focus groups were recorded, transcribed, and qualitatively coded using NVivo software. Within my final analysis, I integrated my comparative analysis with the participatory analysis and qualitative data gathered in focus groups.
Objective 9
The methods described above identified similarities and differences in understandings of soil health across farm type groups and between farmers and agricultural service providers. The analysis yielded recommendations for integrating farmer and agricultural service provider knowledge to improve sustainable soil management and highlighted the importance of visualizing the full suite of social-ecological factors that inform approaches to soil health. This analysis led to ongoing efforts to create tools that support service providers who work with farmers to improve soil health in Vermont and the Northeast.
I identify three main themes that encompass how farmers and Extension professionals discussed soil health: (1) as a holistic concept, (2) in a context-dependent way, and (3) using the Western scientific paradigm centered on chemical, biological and physical soil properties. Following analysis of the meanings of soil health, I explore how farmers and Extension professionals assess agricultural soils. Finally, I explore the factors that enable and constrain farmers in prioritizing or implementing practices for soil health. I focus on enabling and constraining factors that were consistent across farm types, as these seem to hold the greatest potential for supporting farmers in managing soil health across a wide range of contexts.
Of the many ways that farmers and extension professionals spoke about soil health, holistic framings were both common and complex. Many farmers and extension professionals identified soil health as a foundation upon which farm businesses and agroecosystems are built. This concept was often expressed in a direct and economical way; as one livestock farmer stated, “the soil is the basic generator. That interaction between sun, grass and soil is basically the foundation for any money that I make here.” Others expressed a foundational understanding of soil health in more expansive terms. For example, an organic livestock farmer stated,
soil health is essentially the foundation of everything that we do here. I think it's the life force of our ecosystems and our planet, that it's filtering air and water and supporting life above and below, that the cycles of most of the things we're involved with as farmers, production of milk or something, is really this elaborate microbiology of what's happening within the soil and in the [animal’s] rumen and how those two things relate and how nutrients are cycled through that system.
In this quote, we see how conceptualizing soil health as foundational may lead farmers to connect soil health to broader agroecosystems, food systems, and planetary systems. Many interviewees similarly emphasized (agro)ecological relationships between soils, plants, and animals. Holistic conceptualizations of soil health often included socio-economic factors. Within these framings, soil health could be neither conceptualized nor achieved without considering social factors such as on-farm housing, just livelihoods, and policy processes.
There was a very clear divide in who conceptualized soil health in a holistic way. Extension professionals, organic and non-organic livestock farmers, and organic dairy farmers all primarily viewed soil health through a holistic lens. Non-organic dairy farmers, as well as both organic and non-organic vegetable farmers, on the other hand, rarely thought of soil health in a holistic way. One possible explanation for this divergence is that the vegetable farms and non-organic dairies represented in the data had less integrated systems and therefore relied on imported inputs to maintain soil fertility. In vegetable production systems, a holistic view of soil health may be difficult to square with the reality of constantly removing vegetal biomass and importing nutrients and organic matter to replenish soils. Somewhat similarly, non-organic dairy farms often lack sufficient land to supply all their own feed and rely on imported feed. With limited capacity to graze very large herds, non-organic dairies also often rely on synthetic fertilizers to maximize on-farm feed production. Due to heavier reliance on external inputs, such farms may approach soil health in a more chemically oriented or agronomic way.
Many farmers and extension professionals understood soil health to be highly context dependent. As one organic dairy farmer stated bluntly, “soil health is absolutely individual to the land that you’re stewarding.” From this perspective, factors such as soil parent material, topography, climate, and social factors all mediated what might constitute soil health in a given context, with attendant implications for management strategies. A livestock farmer similarly noted that because soil health is so context dependent, “what works well in one place isn’t always the same as what works in another place.” Within this framing, both farmers and Extension professionals emphasized the need to align soil management practices with the particularities of a given farm.
Extension professionals were also highly attuned to the variability of what might constitute soil health in various farm contexts. One Extension professional emphasized that “every farm is such a different situation, and every farm has a different set of issues.” The contextual nature of soil health also complicated extension and outreach; one Extension professional explained, “we don’t always know what the outcomes of practices will be because each farm, each system, is different.” For both farmers and Extension agents who viewed soil health in a contextual way, trial and error was an integral part of identifying the moving target of soil health within unique agricultural settings.
A context dependent conceptualization of soil health was one of the most consistently mentioned conceptual categories across farm types and extension professionals (Table 1). The only outliers were non-organic dairy farmers and organic livestock farmers. Non-organic dairy farmers spoke of tailoring practices to their unique contexts but did not directly identify soil health as a context-dependent concept. Organic livestock farmers, on the other hand, recounted using deep, place-based knowledge to guide soil management; it is possible that for these farmers, the importance of context was so intrinsic that it did not bear explicit mention.
Farmers and extension professionals referred most often to the Western scientific definition of soil health as comprising chemical, biological, and physical soil properties. Some interviewees discussed all three dimensions at once or in relation to each other. It was, however, more common that people emphasized a particular dimension when discussing their understanding of soil health. In general, interviewees discussed the three Western scientific dimensions of soil health with comparable frequency. Below, I explore how soil chemical, biological, and physical properties informed farmers’ and Extension professionals’ conceptualization of soil health and the differences in which dimensions were emphasized across farm types.
Soil chemical properties include macronutrients, micronutrients, and pH. Many farmers emphasized the role that soil chemistry plays in plant nutrient availability. Soil acidity was of particular interest to nearly all farmers. As one non-organic dairy farmer emphasized, “an acidic soil ties up our nutrients so that crops can’t get those nutrients” even if soil tests indicate the presence of nutrients in the soil. The vital role that pH and nutrient availability play in soil fertility and plant growth led many farmers to prioritize soil chemical properties. An organic vegetable farmer explained,
We've really been trying to get the chemical properties up, because when we moved onto this really sandy soil, our soil tests - everything was just rock bottom. I think there've been some issues with that approach… but our soil tests are looking a lot better now than they were.
This farmer exemplifies the connection between soil test results and a conceptualization of soil health that centers soil chemistry. Despite possible issues associated with a narrow focus on chemical properties, this farmer felt encouraged by soil test results and committed to addressing soil chemistry as a primary path to soil health. Due to scientific orthodoxy around plant growth limiting factors and yields, farmers may feel that focusing on soil chemistry is the only path towards financial viability. This possibility seems to align with the experiences of Extension professionals, many of whom found soil chemical properties to be an important ‘on-ramp’ for farmers to discuss soil health. One extension professional summarized, “mostly when I talk to farmers, it’s in this vein of nutrient management planning.”
Other farmers, however, expressed frustration at agricultural policies and support programs focused narrowly on soil chemistry. An exasperated organic dairy farmer asserted, “you can’t extrapolate one nutrient… in doing that, you’re going to perpetuate the same harmful cycles because you’re going to create imbalances on the other end.” Other farmers expressed similar frustration with the statewide emphasis on phosphorus reduction, which they felt reduced financial and technical support for farmers who do not struggle with excess phosphorus but may face other soil health concerns.
Conceptualizations of soil health centered on soil chemical properties differed substantially by farm type. Organic vegetable producers emphasized soil chemistry far more than any other farm type (Table 1). Annual vegetable production requires substantial nutrient inputs to account for the export of nutrients and biomass when produce leaves the farm. In an organic production system, nutrient input options are more limited than in a non-organic production system and may therefore require more careful deliberation. This could explain why organic vegetable producers emphasized a chemical conceptualization of soil health more than their non-organic counterparts. Organic vegetable producers also reported ongoing issues with crop yields, ostensibly due to insufficient macronutrients; providing sufficient nitrogen was a particular struggle in organic vegetable systems.
Organic and non-organic dairy producers also emphasized soil chemical properties in their conceptualizations of soil health. As with organic vegetable producers, this emphasis aligns with dairy farmers' production context. Across both organic and non-organic dairy farms, nutrient management is a key concern in terms of both feed production and manure management.
On the other hand, Extension professionals, non-organic vegetable farms, and both organic and non-organic livestock operations did not heavily emphasize soil chemistry within their framings of soil health. Extension professionals and livestock farmers emphasized other Western scientific dimensions of soil health, such as biological properties, over chemical properties. Extension professionals explicitly conveyed that soil chemistry represents but one small slice of the soil health pie. For livestock farmers, a decreased emphasis on soil chemistry may be due to the nutrient cycling facilitated by animals and the reduced need to purchase inputs to return nutrients to the soil.
Soil biological properties include soil organic matter and soil organic carbon as well as micro- and macro-organisms. Many farmers and Extension professionals emphasized that their interest in and understanding of soil biology has increased substantially in recent years. An extension professional shared, “one thing that I've been really getting more interested in this last year is the soil microbial community because that is a driver of so many pieces of good soil health.” This sentiment was shared by many farmers, who highlighted ways in which soil biology connected to soil, plant, and animal health as well as farm-scale ecological resilience. These linkages varied across farm types, reflecting the particularities of different production systems. For example, a livestock farmer explained that “if you don't have biodiversity in your soil, you're not going to have biodiversity in your plants, which means you're not going to have the nutrition in the cows that you want.” Within pastured livestock systems, farmers connected soil biology to pasture biodiversity and animal health; some even likened soil microbiology to ‘below-ground livestock’.
In vegetable operations, there was an emphasis on the role of soil biology in plant nutrient availability. For example, one organic vegetable farmer described a healthy soil as one with “a lot of mycelium fungus roots that go broadly throughout the soil [facilitating] exchange of nutrients between the various life forms.” This also demonstrates the ways in which both farmers and extension professionals linked soil biology to other dimensions of soil health, such as soil chemistry.
Finally, across all farm types, farmers linked soil biology to moisture regulation and resilience to precipitation extremes. Many focused on the role of soil organic matter. In connecting soil biology to other dimensions of soil health, pasture or crop productivity, and broader processes linked to farm-scale resilience, farmers emphasized soil multifunctionality within their conceptualization of soil health.
References to soil biology as a core component of understanding soil health were even across both Extension professionals and farm types, though organic vegetable farmers emphasized soil biological health slightly more frequently than any other farm group. This aligns with the concerns that organic vegetable farmers expressed around the impact of tillage and cultivation on soil biology. Many organic vegetable farmers emphasized full-season or multi-year cover cropping as an important strategy for mitigating the effects of tillage on soil biology, though few were able to implement long periods of rest due to economic pressures to produce cash crops.
Physical properties refer to soil structure, which is determined by soil aggregates, porosity, and degree of soil compaction. Some farmers, particularly those managing livestock, focused on soil structure in the context of grazing management strategies to avoid compaction. One farmer emphasized that,
Soil physics is guiding most of my decisions. It's like, ‘Don't turn over the earth. Don't do anything to jeopardize positive soil structure.’ It seems like that's the primary goal. Don't compact it, don't squish it. I want good soil, physical characteristics.
This farmer went on to link soil structure to soil biology, emphasizing the importance of creating adequate ‘habitat’ for soil micro- and macro-organisms. More commonly, farmers emphasized the role of soil structure in water infiltration, with many farmers identifying adequate infiltration and a lack of surface crusting and pooling as important components of soil health. Extension professionals also emphasized the link between soil physical properties and water infiltration in their conceptualizations of soil health.
Relative to biological and chemical properties, physical properties were emphasized less frequently in farmers’ and Extension professionals’ understanding of soil health. Organic vegetable farmers emphasized soil structure more often than other farmers, which was, again, linked to their concerns around the amount of tillage and cultivation required to produce annual vegetable crops without using agrichemicals to control weeds.
Extension professionals mainly noted that perceived problems with soil physical properties were core to their work with farmers around soil health. As one summarized, “we address what the farmers perceive as not soil health. What is not soil health - soil compaction. It's saturated all the time.” While these references were not always indicative of how Extension professionals themselves conceptualized soil health, soil physical properties were clearly a part of how they communicated with farmers around soil health.
As with meanings of soil health, we identified many ways that individuals assess soil health. Farmers and Extension professionals emphasized observational methods of assessment in addition to traditional soil tests. The diversity of assessment tools, and in particular the emphasis on qualitative indicators and sensory observation, align with the holistic and context-dependent conceptualizations of soil health identified above. Across diverse contexts and understandings of soil health, there was generally great consistency of assessment methods across farm types and between farmers and Extension professionals, with notable exceptions that I explore below.
In discussing how they assessed soil health, both farmers and Extension professionals emphasized the power of sensory observation grounded in long-term, place-based knowledge. Some farmers mentioned strategies of visual record keeping. Many more stressed the value of long-term, observational knowledge in determining the health of agricultural soils and identifying best practices for soil health. For many participants, observation constituted both a tool to assess soil health and a core component of farm management.
Both farmers and Extension professionals also emphasized the value of bio-indicators in assessing soil health. In assessing plant species as indicators of certain soil conditions, one farmer shared “I understand that when you see certain weeds, that says something about the soil. Not that I can read the tea leaves if you will.” While this particular livestock farmer felt unsure of interpreting bioindicators, others felt more confident and used this method to assess the general state of their soils and how soils responded to management. For example, an organic dairy farmer noted, “we see a lot of wild strawberries and blackberries in pastures that have been depleted of nutrients.” The ways in which farmers rely on observation generally, and bioindicators specifically, aligned with Extension professionals’ primary approach to assessment. All Extension professionals interviewed emphasized careful observation over time as the best tool for assessing soil health holistically. One specifically underscored, “I feel like the power of observation and performance cannot be replaced by a soil health test.” While observation was identified as key for farmers, Extension professionals also emphasized the power of long-term observation in their own work providing guidance and recommendations to farmers. This led Extension professionals to emphasize the need for cultivating long-term relationships with farmers.
Another subset of observational assessment strategies was looking to productivity and yields as indicators of soil health, or lack thereof. This was most often communicated as part of an approach to soil health integrated with wider farm management and decision-making. Many farmers, across farm types, mentioned low yields as indicators of poor soil health and a key motivator in prioritizing soil health. This translated into Extension work as well. All Extension professionals noted that yields constitute a central component of their work with farmers, providing an important entry point into conversations about soil health. For example, one Extension professional shared that they begin soil health conversations by asking farmers, “What are your crops doing? What are your yields looking like?” This underscores how connections between on-farm practices, soil health, and yields may provide a valuable ‘on-ramp’ into wider conversations about soil and agroecosystem health.
Soil tests were the most frequently referenced tool for assessing soil health. In our coding, we included both conventional soil tests and more comprehensive soil health tests in this category. The frequency with which soil tests were mentioned, however, is not necessarily indicative of their use value, as we asked directly about how farmers and Extension professionals view and use soil tests.
In fact, attitudes towards soil testing and application of soil test results were highly variable. Many farmers reported conducting soil tests merely to comply with state policy or organic certification requirements. Organic farmers in particular expressed ambivalence towards the value of soil tests, noting that they were mainly useful in validating observations or identifying specific chemical imbalances. As one farmer summarized, soil tests were seen as useful in “determining deficiencies, but not really for measuring health as a holistic idea.” The tension between soil tests and holistic conceptualizations of soil health was a recurring theme across many farmers and Extension professionals. For example, many interviewees emphasized a desire for more holistic soil tests that centered biological assessments. Ambivalent attitudes make it difficult to determine how soil tests factor into understandings of soil health or farmer decision-making.
The incompatibility of standard soil tests with certain agronomic contexts further complicates efforts to determine the role of soil testing in farmers’ soil health management strategies. For example, livestock farmers and organic dairy farmers expressed frustration that standard soil tests are not calibrated to pastures. One livestock farmer emphasized that “a hay field and a pasture are not the same thing. They don't function the same. The soil cover is not the same. The biodiversity is not the same. The harvest is not the same and those conventional soil tests are not oriented for pastures.” This quote demonstrates the ways in which conventional soil testing may be at odds with a context dependent understanding of soil health.
Finally, there were farmers who relied heavily on soil testing, not as an indicator of soil health, but to guide chemical amendments. This was particularly true for organic and non-organic vegetable and non-organic dairy farmers. A dairy farmer emphasized, “we soil sample every three years. Anything that the soil needs - lime or anything to straighten out the pH, we’ve always done that.” This demonstrates a wide range of utility, wherein some farmers conduct soil tests to supplement primary observational assessment methods, and others take soil test results as a trusted playbook to guide soil amendments but not necessarily broader soil management decisions.
Extension professionals expressed similarly mixed attitudes towards soil tests. Some noted that soil tests are a vital starting point for engaging with farmers around soil health. One individual emphasized soil testing as the base of Extension support, stating “if [farmers] don’t have a soil test, how can I help [them]?” Others viewed soil testing as an entry point for farmers into more complex discussions around soil health. Despite this, however, there was ubiquitous awareness of the limitations of soil tests. For instance, the same individual quoted above went on to say that a soil test “doesn’t really address soil health, except for the chemical aspects of it.” A handful of individuals shared deeper reservations regarding the accuracy of both conventional soil tests and the more comprehensive Cornell Assessment of Soil Health (CASH). One Extension professional, reflecting on perceived discrepancies between observed soil function and CASH results, shared,
We do these soil health tests from Cornell and pretty much every dairy farm I've ever done it on, they get high scores because of the system they're in. That doesn't mean that we're seeing the results that we want to see. You can measure these things but what are the outcomes and are they truly linked to those results?
Overall, Extension professionals and farmers conveyed similarly mixed sentiments regarding the utility of soil tests to holistically assess soil health.
There were many factors that supported farmers in prioritizing soil health. Many of these factors overlap, representing the complex entanglement of social-ecological factors that mediate farmers’ ability to promote soil health. In parsing this complexity, I identified three main factors that supported farmers’ soil health management strategies: access to capital, strong knowledge networks, and access to sufficient land base.
Relative to these enabling factors, however, farmers and Extension professionals more often emphasized factors that constrained efforts to prioritize and promote soil health. Perhaps unsurprisingly, the thematic categories of constraining factors were the inverse of the enabling factors, underscoring the centrality of these issues in mediating processes and outcomes related to soil health. Access to capital, access to land, and lack of supportive networks constituted the most significant barriers farmers faced in promoting soil health.
Farmers repeatedly identified an inability to access sufficient land base as a factor constraining their capacity to promote soil health. When asked directly about the challenges they faced in prioritizing soil health, one livestock farmer succinctly explained “the biggest [challenge] for me is land access.” For some, land access challenges were centered on the acreage that they had access to. Insufficient land base was particularly common amongst vegetable producers, many of whom lamented feeling as though razor thin margins meant they had to plant all their land to cash crops. For other farmers, land tenure rather than land base was the key challenge constraining their capacity to invest in soil health. In certain contexts, this limited farmers’ willingness to implement certain practices. One livestock farmer renting land explained, “Agroforestry just hasn't felt worth investing my time and planning and financing [for] putting trees into land when I don't know how long I'll be there.” Farmers renting land also highlighted the tension between their desire to invest in amending depleted soils and the uncertainty stemming from a lack of secure, long-term tenure.
Inability to afford equipment, inputs, and infrastructure constituted another major factor constraining farmers’ capacity to promote soil health. Nearly all farmers emphasized feeling unable to invest more in soil health and expressed deep frustration with the systemic and structural factors that contributed to financial constraints. For instance, an organic dairy farmer underscored how years of low milk prices placed a financial squeeze on the farm, which limited their capacity to prioritize soil health in a way that aligned with their values. The desire to do more for soil health than present financial realities allowed was a common theme. Across farm types, farmers emphasized that the timescale(s) of benefitting from investments in soil health are difficult to square with economic systems that prioritize cheap food over living wages for farmers. These challenges highlight that socio-economic factors constrain farmers from fully implementing their substantial existing knowledge related to soil health.
While support programs and grants alleviate some of these financial constraints, they also require substantial administrative legwork on behalf of farmers and do not benefit all farmers equally. As an organic livestock farmer noted, “particular farms may not rank high enough to be able to take advantage” of support programs, which they found to be problematic when “financial cost is the biggest prohibitive factor for most farms” implementing practices for soil health. Beyond support programs, some farmers navigated financial constraints by relying on off-farm income. An organic vegetable farmer discussed their partner’s decision to seek full-time work off-farm, explaining, “That income [will] pay for childcare, which [will] allow me to be more focused on the farm whereas these past two years, both of us have been split between childcare and the farm.” Considering childcare costs exemplifies how access to capital extends beyond grants and support programs and reveals how systemic and structural factors mediate farmers’ capacity to prioritize and promote soil health.
The final category of constraining factors encompasses a range of issues that point to a lack of sufficient support for farmers in their efforts to promote soil health. Many farmers expressed a generalized frustration with support programs. As noted previously, applying to financial support programs requires substantial time and effort from farmers, who often have limited capacity to commit to an application process that may not pay out. Farmers also noted the alphabet soup of federal, state-level, and private funding opportunities; while the opportunities are important, farmers expressed uncertainty around what opportunities exist, who qualifies, and what each application process entails. Many farmers expressed a desire for clear guidance and better support navigating the complex landscape of existing support programs.
Interestingly, many farmers translated available financial support into perceived societal valuation of the role of farmers. Farmers interpreted insufficient Extension support as indicative of the University of Vermont failing to value farmers. While farmers expressed deep appreciation for the individuals working in Extension, they also expressed deep frustration with how the University structures and funds Extension agents - specifically, the ways in which a lack of base funding impacts the extent to which Extension agents can support farmers. Many farmers connected the loss of long-term, trusted advisors to the ‘political will’ of the University as demonstrated by their unwillingness to pay Extension staff to support farmers. Others noted that Extension’s funding structure made it difficult to form trusting, long-term relationships at all. Absent reliable support from Extension agents, many farmers reported feeling uncertain about where to go for information on soil health. The impact of Extension funding structures on farmers’ capacity to promote soil health was one of the more unexpected themes within the data and further highlights the role of social factors in mediating soil health practices and outcomes.
My analysis of results aligns with previous research that different actors conceptualize and approach soil health in diverse ways (Lobry de Bruyn & Andrews, 2016; Prager & Curfs, 2016; Winstone et al., 2019; Wade et al. 2021; Mann et al., 2021). Building on existing research, my findings specifically suggest that meanings of soil health vary across farm types. Farmers managing systems reliant on frequent tillage and external inputs (including organic and non-organic vegetable farms and non-organic dairy farms) tended to articulate understandings of and approaches to soil health focused on chemical, biological, and physical soil properties. Farmers managing highly integrated, animal-based operations (including organic and non-organic livestock farms and organic dairy farms) tended to conceptualize soil health in a more holistic way that incorporated both the wider agroecosystem and social factors that mediate soil health outcomes. Extension professionals also emphasized a more holistic framing of soil health.
It is important to note that across all farmers and Extension professionals, soil health was understood, assessed, managed for, and discussed in complex and diverse ways. Nearly all participants drew on multiple concepts, experiences, and frames of reference to communicate how they conceptualize and approach soil health. There are two important implications stemming from this complexity. First, there is substantial potential for miscommunication, misunderstanding, and divergent perceptions of soil health outcomes across diverse actors (Barrios et al., 2006; Wade et al. 2021). This potential is amplified by varying reliance on soil testing and perceived discrepancies between soil test results and observational assessments of soil health (Doran & Parkin, 1994; Romig et al., 1995; Bagnall et al., 2020). Further research clarifying both how well soil testing reflects farmers’ observation of soil function and the degree to which farmers and Extension professionals trust soil test results is urgently needed.
The second implication is that soil health may function as a discourse that farmers and Extension professionals are using to frame conversations, research, practices, and policies centered on soil management. Hajer & Versteeg (2005) define a discourse as “an ensemble of ideas, concepts and categories [expressed in language] through which meaning is given to social and physical phenomena, [and] which is produced and reproduced through an identifiable set of practices.” I contend that the diverse, complex, and sometimes conflicting nature of how farmers and Extension professionals discussed soil health is indicative of the discursive nature of the topic. Understanding soil health as a discourse, rather than as a term encompassing only biophysical processes, has important implications, not only for soil health research, but also for agroecological transitions more broadly. Discourses play an important role in informing individual and collective actions or practices (Fairclough, 2013). Therefore, attending to how soil health research and outreach is conducted and communicated may have important bearing on how information is translated into practice.
A principles-based approach may provide one option for mobilizing diverse discourses of soil health for agroecological transitions. Within agroecology, principles provide a framework for integrating the social and ecological processes that comprise agroecosystems while also enabling flexible pathways for achieving shared goals across diverse contexts (FAO, 2018; CIDSE, 2018). In the context of soil health, my findings suggest that there is a similar need to integrate the social forces and factors that mediate farmers’ management decisions with the ecological dimensions of soil function. Both farmers and Extension professionals emphasized social factors as central components of soil health. This aligns with recent research exploring the importance of social factors in determining farmer adoption of soil health promoting practices (Bagnall et al., 2020). While examples of principles for soil health exist (USDA NRCS, n.d.; Brown, 2018), none of these framings meaningfully integrate the social forces and factors that mediate soil health outcomes. My results suggest that this is a significant omission and may limit the extent to which such principles can support farmer decision-making or mobilize knowledge for transitions towards more just and ecologically resilient agrifood systems. Land access, living wages, childcare, and governance processes were important factors that enabled or constrained farmers’ ability to promote soil health. To attend to this complexity, I advocate for collaborative processes to identify social-ecological principles of soil health that center farmers’ experiences, knowledge, and needs. Collaboration between farmers, researchers, and Extension professionals is key for ensuring that efforts to promote soil health are relevant to farmers in their unique contexts (Bagnall et al., 2020). Such processes would also enable principle-focused evaluations of soil health, which previous scholarship identifies as a valuable method for assessing agroecological outcomes (Patton, 2021). Principle-focused evaluation could provide an important complement to soil tests, which Extension professionals and many farmers considered insufficient for a holistic assessment of soil health.
Importantly, my results also indicate that there may be significant roadblocks to the participatory processes proposed above. On one hand, farmers reported substantial economic pressures that limited their capacity to engage in collaboration, trial innovative practices, or even implement existing recommendations. This coheres with previous research identifying economic factors as constraining farmers’ conservation efforts (White et al., 2021). On the other hand, Extension professionals were limited in their capacity to respond to farmer needs due to their institutional context. Forced to constantly fund their own positions through grants, Extension professionals reported frustration with the need to prioritize grant deliverables and timelines over developing long-term, collaborative relationships with farmers. Farmers also expressed deep frustration with this situation and interpreted the funding structure of Extension as indicative of the University’s lack of political will to support farmers. This research demonstrates how, in failing to fund Extension staff, the University undermines long-term relationships and collaborations. Addressing constraining institutional factors is necessary to strengthen collaborative efforts between farmers and Extension professionals. Specifically, guaranteed base funding for Extension professionals is an important strategy for improving agricultural soil health in the state.
The extent to which the structure and funding of UVM Extension constrains collaborative efforts around soil health constitutes an important finding of this research. Specifically, it highlights how institutional governance processes mediate soil health outcomes. This, in turn, points to larger questions around the role of universities and Extension services in facilitating agroecological transitions. Asking such critical questions may provide an important context for farmers to engage with the politics of agricultural knowledge. In problematizing institutional structures, many of the farmers interviewed began to question how power operates within knowledge networks to mediate both social and ecological outcomes. In this way, soil health may be a powerful heuristic for agroecological transitions in the United States. Future research should explore the potential for soil health practices, research, and discourses to facilitate engagement with the socio-political dimensions of agroecology.
Education & Outreach Activities and Participation Summary
Participation Summary:
I conducted interviews with 34 farmers and 7 Extension professionals. In each interview, I co-created mental models of soil health with research participants. I then created 6 grouped mental models of soil health by farm type and 1 grouped mental model of soil health for Extension professionals. In total, 49 mental models of soil health arose from this research. I conducted 6 farmer focus groups (by farm type) to engage farmers in participatory analysis of the grouped mental models.
I presented this work as part of my doctoral dissertation defense in November 2022. I also led a workshop on co-creating mental models of soil health with graduate students and researchers within the Institute for Agroecology at the University of Vermont. I presented methods and findings from this research in two undergraduate classes and at one seminar in the Plant & Soil Science department at the University of Vermont.
I was unable to present results of this research at conferences due to health concerns tied to the Covid 19 pandemic. Written outputs of this work (including an open-access, peer-reviewed publication and several popular pieces) were also delayed but will be forthcoming in Spring 2024.
Finally, I shared this work with researchers at Coventry University in the United Kingdom. This was part of a methodological exchange that built on a main finding from this work that centered on farmers' reliance on biological indicators of soil health. I was able to share methods for co-creating mental models of soil health while learning about participatory methods for identifying with farmers what species indicate particular aspects of soil quality. This will inform future work to identify bioindicators of soil health in the Northeast.
Project Outcomes
One of the most surprising and potentially impactful findings of this project was the extent to which UVM Extension funding structures mediate farmers’ capacity to prioritize and promote soil health on their farms. Building on this finding, an outcome of this work is ongoing advocacy for increasing base funding to UVM Extension agents who work with farmers. Equally, this research provides evidence of the need to attend to social factors that mediate soil health outcomes, including access to childcare, healthcare, land, and capital. This points to the need for more holistic approaches in outreach, education, policy and support mechanisms that aim to improve or promote soil health in Vermont. Finally, this project identified an effective and powerful method that agricultural service providers can leverage to more holistically understand farmers’ knowledge and decision making context related to soil health and management decisions.
Over the course of this project, my advisor and I gained the following knowledge:
- Soil health is engaged by both farmers and extension professionals as a discourse that encompasses social dimensions in addition to biophysical processes.
- As a result, agroecology may provide an important framework for integrating the social and ecological dimensions of soil health.
- Observation is often more important than soil test results in terms of how farmers assess the health of their soils and how they make management decisions.
I also gained significant experience in co-creating mental models with farmers, and this project demonstrated the efficacy of this method as a tool for integrating diverse types of knowledge, such as those held by farmers and agricultural service providers.
Virtual interviews with 34 farmers and 7 Extension professionals were a success! LucidSpark was a valuable tool for co-creating mental models of soil health with farmers virtually.
Virtual focus groups with 30/34 interviewed farmers were also a success. The online format enabled more farmers to participate by reducing transportation time and costs. We did ensure that farmers without internet access were able to participate. This involved reserving rooms at public libraries near these farmers and sending a research assistant with a laptop to set up virtual participation for farmers at the library.