Farmers thus provide an important node in the research and policy making process, whereby they determine if scientific findings or policy recommendations apply to their specific farming context—through direct observation, personal experience, and experimentation. Understanding the mechanisms of farmer knowledge formation and precisely how farmers learn is essential to integrating farmer knowledge into the scientific literature. As outlined in the farmer knowledge formation framework, farmer ecological knowledge is accumulated over time based on continuous systematic assessment through direct observation, personal experiences, or experimentation. This iterative feedback approach to learning among organic farmers is akin to the scientific method and parallel in approach to adaptive management in agriculture . As highlighted in the results, it is possible for a farmer to acquire expert knowledge within one or two generations of farming alternatively. Documenting this farmer knowledge within the scientific literature—specifically farmer knowledge in the context of relatively new farmers in the US—represents a key way forward for widening agricultural knowledge both in theory and in practice . This finding is significant because it underscores the importance of farmers not as subjects of science but as actors within the scientific community. This study provides one example for documenting farmer knowledge in a particularly unique site for organic agriculture. Future studies may expand on this approach in order to document other contexts with recent but deep agricultural knowledge on alternative farms.
For example, pipp mobile systems when farmers were asked to talk about soil management specifically, several farmers struggled with this format of question, because they expressed that they do not necessarily think about soil management specifically but tend to manage for multiple aspects of their farm ecosystem simultaneously. This result aligns with similar findings from Sūmane et al. across a case study of ten different farming contexts in Europe, and suggests that farmers tend to have a bird’s eye view of their farming systems. Such an approach allows farmers to make connections across diverse and disparate elements of their farm operation and integrate these connections to both widen and deepen their ecological knowledge base.For most farmers, maintaining ideal soil structure was the foundation for healthy soil. Farmers emphasized that ideal soil structure was delicately maintained by only working ground at appropriate windows of soil moisture. Determining this window of ideal soil moisture represented a learned skill that each individual farmer developed through the iterative learning process elaborated in Figure 1. This knowledge-making process was informed by both social mechanisms gained through inherited wisdom and informal conversations and ecological mechanisms through direct observation, personal experiences, and experimentation . As farmers developed their ecological knowledge of the appropriate windows of soil moisture, their ethos around soil management shifted. In this way, over time , these farmers learned that no amount of nutrient addition, reduced tillage, cover cropping, or other inputs could make up for damaged soil structure. Destroying soil structure was relatively easy but had irreversible, long-term consequences and often took years, in some cases even a decade, to rebuild.
This key soil health practice voiced by a majority of farmers interviewed represented a different framing compared to messaging about soil health vis-a-vis extension institutions , where soil health principles focus on keeping ground covered, minimizing soil disturbance, maximizing plant diversity, keeping live roots in the soil, and integrating livestock for holistic management. While these five key principles of soil health were mentioned by farmers and were deemed significant, for most farmers interviewed in this study, the foundation and starting point for good soil health was maintaining appropriate soil structure. Though soil structure is clearly important in NRCS conception of soil health, soil structure is not explicitly considered in the core soil health principles. The results of this study emphasize that the most successful entry point for engaging farmers around soil health is context specific, informed directly by local knowledge. Among farmers in Yolo County—a significant geographic node of the organic farming movement—soil structure is a prevalent concept; however, in another farming context, this entry point may significantly diverge for social, ecological, economic, or other reasons. Each farming context therefore necessitates careful inquiry and direct conversation with local farmers to determine this entry point for engagement on soil health. For this reason, in most cases it may be more relevant to tailor soil health outreach to the local context rather than applying a one-size-fits all model.The capacity to learn and pass on that learning are essential for organic farms to be able to adapt to ever changing social and ecological changes ahead . Across all farmers interviewed, including both first- and second-generation farmers, farmers stressed the steep learning curves associated with learning to farm alternatively and/or organically.
While these farmers represent a case study for building a successful, organic farm within one generations, the results of this study beg the question: What advancements in farm management and soil management could be possible with multiple generations of farmer knowledge transfer on the same land? Rather than re-learning the ins and outs of farming every generation or two, as new farmers arrive on new land, farmers could have the opportunity to build on existing knowledge from a direct line of farmers before them, and in this way, potentially contribute to breakthroughs in alternative farming. In this sense, moving forward agriculture in the US has a lot to learn from agroecological farming approaches with a deep multi-generational history . To this end, in most interviews—particularly among older farmers—there was a deep concern over the future of their farm operation beyond their lifetime. Many farmers lamented that no one is slated to take over their farm operation and that all the knowledge they had accumulated would not pass on. There exists a need to fill this gap in knowledge transfer between shifting generations of farmers in order to safeguard farmer knowledge and promote adaptations in alternative agriculture into the future.Most studies often speak to the scalability of approach or generalizability of the information presented. While aspects of this study are generalizable particularly to similar farming systems in California such as the Central Coast region, the farmer knowledge presented in this study is not generalizable and not scalable to other regions in the US. To access farmer knowledge, relationship building with individual farmers leading up to interviews as well as the in-depth interviews themselves require considerable time and energy. While surveys often provide a way to overcome time and budget constraints to learn about farmer knowledge, this study shows that to achieve specificity and depth in analysis of farmer knowledge requires an interactive approach that includes—at a minimum—relationship building, multiple field visits, and in-depth, multi-hour interviews. Accessing farmer knowledge necessitates locally interactive research; this knowledge may not be immediately generalizable or scalable without further locally interactive assessment in other farming regions. Local knowledge among farmers in US alternative agriculture has often been dismissed or overlooked by the scientific community, policymakers, industrial drying rack and agricultural industry experts alike; however, this study makes the case for inclusion of farmer knowledge in these arenas. In-depth interviews established that farmers provide an important role in translating theoretical aspects of agricultural knowledge into practice. It is for this reason that farmer knowledge must be understood in the context of working farms and the local landscapes they inhabit. As one of the first systematic assessments of farmer knowledge of soil management in the US, this research contributes key insights to design future studies on farmer knowledge and farmer knowledge of soil. Specifically, this study suggests that research embedded in local farming communities provides one of the most direct ways to learn about the substance of farmer knowledge; working with the local UCCE advisor in combination with community referrals provided avenues to build rapport and relationships with individual farmers—relationships that were essential to effective research of farmer knowledge. Farmer knowledge of soil management for maintaining healthy soils and productive, resilient agriculture represents an integral knowledge base in need of further scientific research. This study provides a place-based case study as a starting point for documenting this extensive body of knowledge among farmers. It is our hope that this research will inspire future studies on farmer knowledge in other contexts so that research in alternative agriculture can widen its frame to encompass a more complete understanding of farming systems and management motivations—from theory to practice.
A fundamental challenge in agriculture is to limit the environmental impacts of nitrogen losses while still supplying adequate nitrogen to crops and achieving a farm’s expected yields . To balance among such environmental, ecological, and agronomic demands, it is essential to establish actual availability of nitrogen to crops . A holistic, functional understanding of plant N availability is particularly imperative in organic agriculture, as in this farming context, synthetic fertilizers are not applied and instead, production of inorganic N—the dominant form of N available to crops—depends on internal soil processes . In organic agricultural systems, farmers may seasonally apply cover crops or integrate livestock as alternative sources of nitrogen to crops—in addition to or in place of using organic fertilizers. In applying these alternative sources of nitrogen to soil, organic farmers rely on the activity of soil microbes to transform organic N into inorganic forms of N that are more readily available for crop uptake . Currently, the predominant way crop available N is measured in organic agricultural systems tends to examine pools of inorganic N in soil . Inorganic N, or more specifically ammonium and nitrate , represents the predominant forms of N taken up by crop species in ecosystems where N is relatively available, such as in non-organic agricultural systems that apply inorganic fertilizers . However, in organic systems, crop available N is largely controlled by complex soil processes not adequately captured by simply measuring pools of ammonium and nitrate. First, because nitrogen made available to crops is controlled by soil microbes—wherein crops only have access to inorganic forms of N after microbial N transformations occur to first meet microbial N demand—pinpointing the flow of N moving through inorganic N pools as a result of these microbial N transformations is necessary to accurately measure actual N availability to crops . Second, extensive recycling of N among components of the plant-soil-microbe system complicates relying solely on measurements of inorganic N pools, which do not reflect these dynamics . As an example, one previous study in organic vegetable systems showed examples where inorganic N pool sizes in the soil were measured to be low, yet there existed high production and consumption rates of inorganic N . This outcome highlighted that if the turnover of inorganic N is high—for instance, high rates of soil ammonium production exist in the soil with simultaneously high rates of immobilization by soil microbes and high rates of uptake by plants—measured pools of inorganic N may still be low . This study also showed that conversely, there may also exist situations when inorganic N pools are low and rates of ammonium and nitrate production are also low, in which case N availability would limit crop production. In organic systems especially, higher carbon availability as a result of organic management can increase these microbially mediated gross N flows, thereby increasing N cycling and turnover of inorganic N . Thus, we hypothesize that measuring total production of ammonium from organic N, or gross N mineralization, and subsequent total production of nitrate from ammonium, or gross N nitrification, may provide a more complete characterization of crop available N in the context of organic systems . Though the application of such diverse management practices on organic farms is known to affect rates of N cycling in soil , measuring N flow rates as a proxy for crop available N is currently uncommon on working organic farms. The current historical emphasis on measuring inorganic pools of N in organic agriculture was originally imported from non-organic farming, wherein the Sprengel-Liebig Law of the Minimum was a widely accepted agronomic principle . In practice, this Law of the Minimum placed particular importance on using artificial fertilizers to overcome so-called “limiting” nutrients—namely, inorganic forms of N. Because inorganic N is relatively straightforward to measure, focus on quantifying pools of inorganic N has since become common practice among agronomists and agricultural researchers . However, the continued acceptance of the Law of the Minimum in organic agriculture underscores the gap in a functional understanding of organic agricultural systems, in particular the role of soil microbes in mediating N cycling.