No abstract

Legume cover crops can play a valuable role in maintaining and increasing soil quality and nitrogen availability, but are infrequently grown in the Upper Midwest due to short growing seasons with minimal management windows; cold, wet springs; and harsh winters. This study was performed to assess the viability of winter annual legume species in northern climates as a potential source of nitrogen (N) fertility to a 75-day sweet corn (Zea mays convar. saccharata var. rugosa) cash crop in Lamberton and Grand Rapids, MN in 2016 and 2017. Treatments included medium red clover (Trifolium pratense), two coldhardy ecotypes of hairy vetch (Vicia villosa Roth), a cereal rye-hairy vetch biculture (Secale cereale L., Vicia villosa Roth), cereal rye as a non-legume control, and a fallow weed-free control. Legumes were split into rhizobia inoculated and non-inoculated treatments. Inoculation had no effect on nodulation, biomass production, or N fixation likely due to competition with endogenous rhizobia strains. The rye monoculture and biculture produced the most biomass at all site-years averaging 7.7 and 7.0 Mg ha -1 respectively while the two vetch ecotypes averaged 4.5 and 3.9 Mg ha -1 . Both vetch ecotypes contributed among the most nitrogen in all site-years, contributing up to 211 kg N ha -1 from aboveground biomass. Data from natural abundance isotopic approaches indicate that 75% of vetch tissue N in Grand Rapids and 59% of vetch tissue N in Lamberton was derived from atmospheric N fixation, with equal or higher percent fixation of vetch in biculture at all site-years. More studies should be performed to better understand controls on N fixation of legume cover crops in cold climates.

Interacting with practitioners and understanding multiple, contradictory, and complex perspectives is an important skill for effectively managing terrestrial resources in the 21st century. Addressing these needs requires innovative approaches in higher education that elevate student learning outcomes and emphasize the affective learning domain through meaningful, place‐based interactions with practitioners. We describe an approach taken to expand a traditional soils field course to include emphasis on higher‐level student learning outcomes in the affective learning domain. Following the completion of a week‐long field study course in which students gain skills in soil description, classification, and interpretation, the expanded second module of the course includes a traveling component in which students experience soils, landscapes, and “lifescapes” (i.e., the lived experiences of practitioners). This second module incorporates practitioners as the primary source of knowledge and is structured to encourage dialogue, understanding, and co‐discovery centered around soils and land management. In unstructured narratives, students identified themes in the affective domain—deep collaboration, personal and professional development and sense of place, community, and joy—as transformational experiences in the course that influenced their personal and professional growth and future ability to interact with people from across the geographic, social, and political spectrum.

IntroductionAgroecology has multiple beginnings in diverse knowledge systems, growing practices, and social movements which, as a whole, seek systemic transformation to build just food system futures. As graduate students, we have been inspired by agroecological movements and practitioners and endeavored to build our knowledge and capacities as agroecologists. Over the course of seven years, we have worked collectively with an evolving cohort to build relationships, understand critical lineages, and practice participatory processes that we found necessary for our development as agroecologists at the University of Minnesota-Twin Cities. Building on this work, we sought to refine an emergent understanding of the necessary components of an agroecological pedagogy.MethodsWe thus hosted a series of workshops in summer 2019 to facilitate collective reflection and development of a pedagogy, which we further refined through collective autoethnography.ResultsThe resulting model contains five key components: a cohort at the heart of the model to facilitate collective learning; critical inquiry as the foundation of knowledge production; relational centering as the basis for building and maintaining care-based relationships with self and others; participatory practice as a space for taking action through and within relationships; and situated knowledge to recognize the unique and incomplete knowledge that each individual brings to their work.DiscussionWe imagine this model as the basis for a dedicated agroecology graduate program, and we close by sharing ongoing implementation efforts, key areas for further development, and our hopes for continued integration with broader movements. Ultimately, we have experienced this process as a transformational agroecological space and hope others are inspired to adapt, imagine, and enact the process, model, and principles in their own places and communities.