Source: UNIV OF MINNESOTA submitted to
A MULTI-REGIONAL APPROACH FOR SUSTAINED SOIL HEALTH IN ORGANIC HIGH TUNNELS: NUTRIENT MANAGEMENT, ECONOMICS, AND EDUCATIONAL PROGRAMMING
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
1010608
Grant No.
2016-51300-25722
Cumulative Award Amt.
$1,523,708.00
Proposal No.
2016-04404
Multistate No.
(N/A)
Project Start Date
Sep 1, 2016
Project End Date
Aug 31, 2021
Grant Year
2016
Program Code
[113.A]- Organic Agriculture Research & Extension Initiative
Project Director
Grossman, J.
Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108
Performing Department
Horticultural Science
Non Technical Summary
Season-extending high tunnel production has been expanding rapidly across the U.S., offering organic growers an exciting new option for production. High-tunnel production is characterized by increased productivity, but due to intense cultivation strategies, high tunnels pose many challenges for sustainability, soil health, and environmental quality. The long term goal for this integrated project (Research, Education), based on extensive feedback from growers, is to develop a comprehensive and economically viable model to address soil health issues in high tunnels across a wide geographic reach, resulting in increased adoption of practices such as legume cover crop incorporation that promotes sustainable management of organic high tunnels and financial stability for farmers. We propose to evaluate a range of farmer-selected rotations in three distinct regions ranging from the far north to the south, build a predictive understanding of soil quality management and economics of season extension, and facilitate knowledge exchange via University coursework, organic information clearinghouses (hightunnels.org, eOrganic), and community partners (NGOs), with a focused emphasis on limited-resource farmers and historically underrepresented groups. We will develop three organic agriculture course modules, a hands-on short course addressing issues and applicability of high tunnels for limited-resource growers, a mobile nutrient management phone app, and a webinar series. We will also work closely with NRCS' new Division of Soil Health to connect to existing resources, network farmers, and expand resources via our project results. Our project is designed to have far-reaching implications for how farmers manage their high tunnels for optimal soil health and economic returns.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1010110107070%
6031460301020%
9030110302010%
Goals / Objectives
High tunnel (HT) production has been expanding rapidly across the United States, offering organic growers an exciting, new option for production. High-tunnel production is characterized by increased productivity and protection from extreme weather events and foliar disease. However, because of the intense cultivation strategies, often with large compost additions, HT's pose many challenges for sustainability, soil health, and environmental quality. These challenges could offset the economic gains that HT production offers, which is largely unexplored in a holistic way. Thus, our long term goal, based on extensive feedback from growers, is to develop a comprehensive and economically viable model to address fertility and soil health issues in HT's across a wide geographic reach, resulting in increased adoption of practices such as legume cover crop incorporation that promote sustainable management of organic HT's and financial stability for farmers. We will accomplish this by conducting networked experiments across a North-South gradient of research sites and by training students and limited-resource farmers excited about using season extension to increase food security and marketing opportunities. Our unique team of researchers and educators is well poised to bring this goal to fruition, with expertise in organic production systems, high-tunnel management, food and agricultural economics, and soil quality. Outcomes include practical, research-based information on conservation and economic benefits of rotations, and allow for improved Organic Systems Plans by broadening viable options for nutrient management and rotation in HT's
Project Methods
Advisory Board: We will develop a multi-region advisory board including ten stakeholders from our three sites, compensated for their participation. Our advisory board will meet twice annually, bringing together as many of our members in a face-to-face venue as possibleSoil Quality Experiments: We will develop an extensive research network to guide this project, and also to maintain a high tunnel soil fertility research community that outlives the life of this project. In order to develop recommendations and data that are relevant and useful across a wide geographic range, as part of this project we will develop a community of practice across three climatic zones in the U.S. ranging from cold northern climates in Minnesota (USDA Hardiness Zone 3-4; PD Grossman), the Great Plains in Kansas (Zone 5-6; Co-PD Rivard) and the Mid-South in Kentucky (Zone 6-7; Co-PD Jacobsen). At each site we will develop two associated replicated experiments, designed to 1) model system-level effects of cover crop legume integration (Cropping systems experiment) and 2) identify best establishment practices for soil N acquisition (Cover crop windows experiment).Economic Evaluation Experiments: Together with our economics team, we will assess farmers' willingness to adopt the proposed nutrient management plans, accounting for economic returns and farmers' valuation of soil improvements and ecosystem services. This will be accomplished primarily through a partial budgeting approach and a farmer survey. The partial budgeting approach will use data collected from the experiment sites and a phone survey to wholesalers and retailers of local, organic produce. A farmer survey will incorporate a valuation section to elicit farmers' values for soil resources.Education about High Tunnels: We will facilitate knowledge exchange about high tunnel management to university students and underrepresented groups through new curriculum design and experiential learning. Three hands-on course modules will be developed and shared across existing KY, MN and KS curricula, as well as for use by our collaborating non-profit organizations in each region. We will also develop a unique integrated one-week short course in Appalachia (Eastern KY) for students in all three states to learn about the use of tunnels in under-resourced regions of the U.S. where regular access to fresh and affordable produce is challenging. The field course will be taught as an elective as part of the new University of Minnesota undergraduate Food Systems major and the Kansas State University Urban Food Systems Practicum graduate course, both of which heavily-emphasize experiential learning in food system and agricultural education. A valuable output of our curriculum work is the development of a mobile tool (i.e. 'smartphone app') to use in our classrooms to help students understand nutrient cycling as related to cover crops, as well as aid farmers in decision-making on their farms. The app will determine the amount of N delivered via a cover crop planting based on common legume N concentrations, recorded biomass or height/density measurements, and rate of N release based on N-release equations under different soil types, temperature, and moisture conditions. The fourth educational tool we will develop is a webinar series in Y4 that will be archived online via the hightunnels.org and eOrganic websites. We will develop a series of three webinars, each describing management practices and lessons learned via our project in each site.

Progress 09/01/16 to 08/31/21

Outputs
Target Audience:Research results and related resources have been shared with a wide variety of grower groups and students over the life of the project, including Appalachian, Hmong, refugee, indigenous and urban farmers, as well as NRCS and Extension professionals serving these audiences. We estimate to have reached over 1000 individuals via presentations given throughout this five-year project (415 in MN, 425 in KS, and 280 in KY). In addition to this number, we reached 1300 via an NRCS webinar series (see below). During our final (and primary) reporting years of 2019-2021, in-person outreach and visits to the experimental sites was hindered by covid-19, yet expect that we reached significantly more individuals via virtual events. Here we summarize key non-conference events, including field days, classrooms, and workshops. The citations for events from the final product year (2021) are found in the 'Products' and 'Other Products' sections. Other products can be found in past annual progress reports. One of the most important target audiences in this project was NRCS service providers. In 2021, we met our target goal of three national webinars, sharing information with over 1390 attendees and via presentation downloads, 527 of these represented by the final webinar emphasizing soil health data resulting from the project. A second significant educational output from this project was an experiential learning delegation to Kentucky (May-June, 2019) that provided an opportunity for ten students from three states to learn about historical and current challenges and opportunities for sustainable agriculture in Appalachia. Learning opportunities included site visits of historical or commercial importance, and a hands-on high tunnel build with Grow Appalachia, a local NGO working to promote sustainable agriculture in the region. Every student responding to our post-trip survey reported increased knowledge of Appalachian agriculture, challenges to food access, and high tunnel construction and management. Student comments included: "I gained so much perspective on Appalachian food systems and on how the general-public understands food systems" (Student 1); "I brought ideas and inspirations back to our college farm in hopes of broadening our horizons while simultaneously refining some of our goals. Many ideas and experiences are still ruminating as inspiration that will be utilized as I pursue a career in nonprofits that work with agriculture" (Student 3). A third important event (February, 2020) was invitation to lead a full-day 'Organic University' workshop at the premier organic farming gathering, the MOSES Organic Farming Conference. This 6-hour event included organic farmer Hallie Anderson from Minnesota and three project team members. We reported project results, as well as provided resources and recommendations to 60 organic high tunnel producers. Evaluations demonstrated that 94% of all attendees learned something new, with most informative parts of the program being organizational information, cover crop integration, high tunnel soil nutrient management and environment, pros and cons of different high tunnels, crop rotations and soil health. When asked to rate their knowledge of how high tunnel management affects soils, water, and pests, participants stated 'somewhat low to medium' knowledge before the workshop to almost all stating 'somewhat high to high' following the workshop. All areas of learning increased participant knowledge in similar ways. Most learning occurred in the areas of cover crop rotations, calculation of fertility benefits, stationary/moveable tunnel differences, and economic management. The project also reached undergraduate and graduate student audiences, and middle and high school students. Three teaching modules based on project research for use in undergraduate level courses were developed covering 1) an introduction to high tunnels, 2) high tunnel rotations and pest management, and 3) soil management. These modules have now been incorporated into existing courses in each state focusing on organic (KY and MN) and urban agriculture (KS). As well as the cross-project outputs above, several significant target audiences were reached in each of our project regions. In Minnesota, we reached a wide diversity of stakeholders, including many non-traditional and BIPOC farmers, via presentations at events such as the Bimaaji'idiwin Gitigaan, a farmer training program on the Fond du Lac reservation (April, 2019), the Great Lakes Indigenous Farming Conferences (Feb, 2020), thee MN Organic Conference in St. Cloud, MN (Jan 2018), the Sustainable Farming Association Conference (March, 2018), and the MOSES Organic Farming Conference (all years). The results from the soil health valuation work were presented at the Joint Meeting of Agricultural and Applied Economics Association and Western Agricultural Economics Association (August 2021). In Kansas across the life of the project, results were delivered to the Juniper Gardens Refugee Training Farm (Kansas City, KS) both formally and informally. Co-PI Rivard collaborated with Juniper Gardens Training Farm Program Manager, Semra Fetahovic, to plant a demonstrational cover crop on their farm. Ms. Fetahovic was given teaching materials and delivered formal instruction on soil health and cover cropping practices to refugee farmers. The work of the project was also delivered during nine field days (one virtual), four workshops, seven regional growers' conferences, and numerous tours and other training events in Kansas. Direct results from the project were delivered to Growing Growers Kansas City Farm apprentices during the soils workshop and vegetable research field day throughout the project period. Growing Growers KC is a beginning farmer apprenticeship program that utilizes workshops and apprenticeships at local organic farms (growinggrowers.org). In Kentucky (University of Kentucky, UK), over the life of the project 29 events reached our target audiences, including presentations to 12 UK courses, 3 field days, 4 regional conferences, 5 state meetings, and 4 county-level meetings. Specifically, results of the project were directly delivered to agriculture service providers (Cooperative Extension Agents, Organic Transition Trainers, and Extension Specialists) at three field day at the University Horticulture Research Farm in Lexington, Kentucky. These events included tours of the field experiments. Producers throughout the Southeastern US were exposed to the project through two sessions (one per year) on high tunnel production and marketing challenges at the Southern Sustainable Agriculture Working Group Annual Conference in Little Rock, Arkansas which incorporated sections on cover cropping challenges and strategies in high tunnels. Conventional and organic producers were exposed to the project in a presentation including project results at the SE Fruit and Vegetable Growers Annual Conference in Savannah, GA. Organic producers, state government officials and service providers in the greater Kentucky area were exposed to the project during a session on Successful Organic High Tunnel Production at the Organic Association of Kentucky (OAK) conference, which was presented by co-PI Jacobsen and a team member from one of our NGO project partners at Grow Appalachia (Mark Walden). Four other state meetings included sessions at OAK Annual conferences and the Kentucky Fruit and Vegetable Grower's Annual conference. Undergraduate students in the UK College of Agriculture, Food and Environment were reached through field and lab activities associated with the Sustainable Agriculture Undergraduate Degree Program. Changes/Problems:Two of our key staff have left the project (Pfeiffer, Gieske), and covid-19 has reduced the pace of laboratory operations. This has slowed progress toward the milestone of peer reviewed manuscript publication reporting on the project. What opportunities for training and professional development has the project provided?Over the 5 project years, the project has supported professional development for two post-doctoral students, two graduate students (UMN and KS), and ten undergraduate students. Dr. Fucui Li, a first post-doc supported by the project, is now a faculty member in China. Dr. Miriam Gieske, second post-doc researcher, is now an ecology faculty member at the University of Minnesota, Morris. Ashlee Skinner, Master's student at Kansas State University, also finished her M.S. thesis and is now an Extension Associate at the University of Florida. Dojin Park, a PhD student in applied economics, successfully completed his course work and oral prelim during the course of the project. Ammar Al-Zubade and Dr.Debendra Shresth were both research analysts in Jacobsen's lab working on the trace gas aspects of the project. Shresth now a post-doctoral associate at the University of Wisconsin-Madison working on nutrient cycling modeling and N fate. Undergraduate student Ada Fitz-Axen did independent research on spinach production in the project's cover crop windows experiment and presented results at the University of Minnesota research symposium and is currently applying to graduate programs. Finally, at the University of MN and KSU, six additional undergraduates (UMN: Tanner Beckstrom, Martina (Mar) Horns, Kai Leung, Emily Locke, and Heidi Schlinsog; K-State: Cassidy Fleck and Jessica Mascote) learned basic field and lab techniques, introducing them to opportunities in scientific research. One high school student in KS, Luke Lebar, was also trained. While not financially supported by the project, two additional UMN undergraduates (Sarah Duber and Lucia Carlson) and two Macalester College interns (Zala Cok, Talia Berkstrom), were exposed to the project via occasional fieldwork and project reports. Finally, the project provided training to 4 high school students of color from North Minneapolis during a 2d educational program to learn about high tunnel production in Madison, Wisconsin, in partnership with NC-SARE Youth Educator Grant YENC19-137, and Marcus Kar, Program Director of the Youth Farm urban youth development organization in Minneapolis/St. Paul. How have the results been disseminated to communities of interest?Outputs presented in the Products and Target Audience What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Key findings showed that cover crops produced substantial amounts of biomass and impacted soil nitrogen (N) cycling and associated soil biological characteristics in all three regions. Our results suggest that organic farmers using high tunnels have multiple options to fit a cover crop into their system, however trade-offs exist relative to costs associated with cover crop management and savings provided via cover crop N contribution, and loss of income from cash crop that may be replaced by cover crops. By providing growers with clear data about the soil health, crop yield, and economic considerations posed by cover cropping systems, this project provided data to help farmers better understand these trade-offs. Long term outcomes include knowledge that could serve to reduce detrimental impacts fertilizer overapplication, such as phosphorus run-off, as well as the positive soil health impacts of cover crop inclusion in high tunnel rotations. Goal 1: Across the five years of the project, two experiments were carried out to evaluate the impact of cover cropping systems on soil attributes. Experiment 1 evaluated the degree to which overwintered hairy vetch affected nutrient cycling, biological indicators across the three study sites. Soil mineral N data suggests that within the evaluation period of this study, winter vetch production may result in services related to N retention than N contribution. For example, soil mineral N was generally higher where vetch was not sown relative to the vetch treatment. The hairy vetch cover crop also did not contribute appreciably to mineral N pools four weeks following termination in all site years.While soil mineral N generally trended upwards in the four weeks following vetch cover crop termination, this occurred in all plots including the control where no vetch was sown. Interestingly and in contrast to soil mineral N, at all sites potentially mineralizable N (PMN) was typically higher in the vetch treatment than in the control plots, and frequently increased over the four-week period following cover crop termination. This suggests that while N contributions from vetch may not be apparent in the short-term (4 weeks) following termination, there may be a pool of un-mineralized N that may become available over a longer time frame. No differences were identified in POX-C between plots with vetch those without, yet POX-C trended towards being frequently greater in the vetch treatment than in the control across several site years and sampling periods. Additional soil data (enzyme, PLFA, microbial biomass and soil moisture and temperature) is being analyzed. Two manuscripts are pending, with submission of the first by the end of 2021, and the second soils-focused manuscript by the end of 2022. Experiment 2 ("cover crop windows") evaluated the potential of three cover crop scenarios in high tunnels, identifying cover crop species and planting date combinations that produce optimal nitrogen management during narrow windows of planting time in each of our three regions. This experiment includes cover crop and weed biomass samples as soil samples focused more intensely on nitrogen cycling questions. Rotations included 1) warm season summer cover crops (cowpea and cowpea/sorghum sudangrass), 2) winter-killed fall cover crops (millet, and millet/cowpea), and 3) overwintered cover crops (vetch and vetch/rye). In all states, Legume-grass mixtures usually produce more biomass than legume cover crops alone. Mixes often had reduced legume biomass, which likely reduced the N contributed via biological nitrogen fixation. In Minnesota, cowpea/sorghum sudangrass treatment consistently produced the highest cover crop biomass (driven by sudangrass), followed by vetch/rye and cowpea treatments. In all regions, the winter-killed crops of millet, and millet/cowpea, had low biomass relative to the other seasonal windows. Cowpea plots appeared to positively impact available soil N in some regions three weeks after termination and biomass incorporation, with nitrate levels increasing in plots in Minnesota and in Kansas relative to the cowpea/sudangrass mix. An additional project was carried out in KS (graduate student Skinner) to investigate arthropod diversity related to cover crop presence in high tunnels, demonstrating that arthropod diversity was strongly impacted by soil organic matter content and soil moisture, with mites representing a majority of species present. Results are expected to be submitted for publication by mid 2022. Greenhouse gas emissions results indicate that trace gas flux patterns and cumulative total fluxes differ more by microclimate between the open field and inside tunnels than by practices within the high tunnels. Goal 2: Two economic analyses were performed to quantify farmer valuation of soil health and the financial impact of cover crop use on enterprise returns. A survey developed with a conjoint instrument was finalized after feedback from soil experts and the project advisory board members. The survey was distributed to participants at the 2020 Minnesota Organic Conference and MOSES Organic Farming Conference. Preliminary analysis suggests the survey instrument is effective in estimating values that farmers place on different improvements in soil health. An online version of the survey was designed and distributed to other channels, such as a contact list of farmers at the FairShare Farm and the Organic Broadcaster newspaper at the MOSES, to reach target sample size for reliable statistical analysis. Additional responses were collected during the winter of 2020. In addition to soil and plant data (Goal #1), we compiled economic data for each cover cropping system, including labor inputs and material costs. Data were cleaned to account for differences in sampling and tested using an ANOVA to explore the statistical significance of treatment effects. Data was analyzed using a partial budget method to explore the economic impact of cover crop use on subsequent cash crop returns. Results indicate that the material and labor costs associated with cover crop establishment, maintenance and termination outweighed N fertility benefits, thus producing a negative net change in income for subsequent cash crop enterprises. Negative changes in income were further exacerbated in when the cover crop replaced a winter/early spring cash crop, suggesting that the opportunity costs of cover crop use far outweigh any fertility benefits observed. The economic results have important implications for organic growers who are required under the USDA National Organic Program to incorporate soil building practices, such as cover crops, into their rotation schedule. Two manuscripts are pending, with one submission anticipated by the end of 2021 and another by May 2022. Goal 3: While covid-19 reduced the number of planned events, we were still able to bring results to an estimated 800 individuals, including both virtual and in-person events. The most impactful and high profile of these events was most likely the MOSES Organic University where we reached 60 organic farmers interested in high tunnel production. As part of this event, a 100- page book was developed that included all presentations, as well as numerous additional print resources on high tunnel management. Finally, as a team we updated the hightunnel.org website to include updated resources from multiple sources focusing on high tunnels generally, and more specifically high tunnel soil management.

Publications

  • Type: Theses/Dissertations Status: Published Year Published: 2021 Citation: Skinner, A. Monitoring Belowground Arthropods Associated with Cover Crops in Great Plain High Tunnel Systems. 2021 Kansas Rural Center Farm and Food Conference, August 6, 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Park, D., Agricultural and Applied Economics Association-Western Agricultural Economics Association Joint Meeting, The Valuation of Soil Health Improvements and Ecosystem Services among Crop Producers in the U.S., Virtual. (Aug 2, 2021).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Grossman, J. M., Mid-Atlantic Fruit and Vegetable Convention, "Improving Soils in High Tunnels with Cover Crops," Virtual. (February 9, 2021).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Grossman, J. M., Great Lakes Fruit, Vegetable & Farm Market EXPO, "Observing and Assessing Soil Health Indicators on your Farm," Virtual. (December 9, 2020).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Grossman, J. M., Great Lakes Fruit, Vegetable & Farm Market EXPO, "Virtues of Cover Crops to Support Soil & Crop Health," Virtual. (December 9, 2020)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Locke, E., Gieske, M., Gutknecht, J., and Grossman, J. 2020. Evaluating Enzyme Activity in Agricultural High Tunnels Compared to Open Fields in Minnesota and Kentucky. UMN Undergraduate Research Symposium. Virtual Presentation accessed at Emily Locke.


Progress 09/01/19 to 08/31/20

Outputs
Target Audience:In year 4 of the project, our plans for dissemination of results were greatly impacted by covid-19. Many of our regular venues for presentation, such as the UMN and Southwest Research and Outreach Center's organic field days, were cancelled. However, prior to restrictions, we shared our experimental results with organic farmers, indigenous and minority farmers, and Natural Resource Conservation Service (NRCS) staff. We presented the first in a series of three webinars as part of NRCS' organic agriculture webinar series, with 462 people registering for the webinar and 212 attending. In February, 2020 our project team was honored to be invited to lead a full-day 'Organic University' event at the premier organic farming gathering in the United States, the MOSES Organic Farming Conference. This 6-hour event included organic farmer Hallie Anderson from Minnesota and three of our project team members. We reported on project results to date, as well as provided resources and recommendations to over 60 organic high tunnel producers. Evaluations demonstrated that 94% of all attendees learned something new, with most informative parts of the program being organizational information, cover crop integration, high tunnel soil nutrient management and environment, pros and cons of different high tunnels, crop rotations and soil health. When asked to rate their knowledge of how high tunnel management affects soils, water, and pests, participants stated 'somewhat low to medium' knowledge before the workshop to almost all stating 'somewhat high to high' following the workshop. All areas of learning increased participant knowledge in similar ways. Most learning occurred in the areas of cover crop rotations, calculation of fertility benefits, stationary/moveable tunnel differences, and economic management. In addition to farmers, the project also reached undergraduate and graduate student audiences, as well as middle and high school students. A series of three teaching modules based on project research for use in undergraduate level courses were developed covering 1) an introduction to high tunnels, 2) high tunnel rotations and pest management, and 3) soil management. In addition, we organized and carried out an experiential learning trip for BIPOC youth to a range of high-tunnel based agricultural enterprises in and around Madison, WI. During the Madison visit, a video was produced highlighting soil health topics specifically relevant to high tunnel environments and innovative high tunnel management strategies, targeted toward college student and farmer audiences. These videos are in the final stages of production. In Kansas, results of the project were delivered to the Juniper Gardens Refugee Training Farm (Kansas City, KS) both formally and informally. Co-PI Rivard collaborated with Juniper Gardens Training Farm Program Manager, Semra Fetahovic, to plant a demonstrational cover crop on their farm. Ms. Fetahovic was given teaching materials and delivered formal instruction on soil health and cover cropping practices to refugee farmers. The work of the project was also delivered during three field days, two workshops, three regional growers' conferences, and numerous tours and other training events in Kansas. Direct results from the project were delivered to Growing Growers Kansas City Farm apprentices during the soils workshop and vegetable research field day. Growing Growers KC is a beginning farmer apprenticeship program that utilizes workshops and apprenticeships at local organic farms (growinggrowers.org). In Kentucky, results of the project were directly delivered to agriculture service providers (Cooperative Extension Agents, Organic Transition Trainers, and Extension Specialists) at a field day at the University Horticulture Research Farm in Lexington, Kentucky. This event included tours of the field experiments and a demonstration of the app being developed by the project. Producers throughout the Southeastern US were exposed to the project through a session on high tunnel production and marketing challenges at the Southern Sustainable Agriculture Working Group Annual Conference in Little Rock, Arkansas which incorporated sections on cover cropping challenges and strategies in high tunnels. Organic producers, state government officials and service providers in the greater Kentucky area were exposed to the project during a session on Successful Organic High Tunnel Production at the Organic Association of Kentucky conference, which was presented by co-PI Jacobsen and a team member from one of our NGO project partners at Grow Appalachia (Mark Walden). Undergraduate students in the UK College of Agriculture, Food and Environment were reached through field and lab activities associated with the Sustainable Agriculture Undergraduate Degree Program. Changes/Problems:Two of our key staff have left the project (Pfeiffer, Gieske), and covid-19 has reduced the pace of laboratory operations. This has slowed progress toward the milestone of peer reviewed manuscript publication reporting on the project. What opportunities for training and professional development has the project provided?During this reporting period, the project has supported professional development for one post-doctoral student, two graduate students (UMN and KS), and six undergraduate students (in addition to those supported last reporting period). Miriam Gieske, post-doctoral researcher at the University of MN, has learned project management skills, and advanced her knowledge of soil assays and high tunnel field management. In July 2020 Miriam defended her PhD thesis and moved into a faculty position at the University of Minnesota, Morris where she is faculty of Ecology. Ashlee Skinner, Master's student at Kansas State University, also finished her M.S. thesis in this reporting period. Dojin Park, a PhD student in applied economics, furthered his understanding of developing an instrument to elicit farmers valuation of soil health. He also interacted with potential respondents as he distributed the survey instrument at MOSES Organic Conference. He also successfully completed his oral preliminary exams using his work on this project as part of his dissertation and became a PhD candidate in applied economics. Ammar Al-Zubade, a PhD student in the Integrated Plant and Soil Science Program at the University of Kentucky successfully completed his written and oral preliminary exams and became a PhD candidate. Dr. Debendra Shrestha, research analyst in Jacobsen's lab working on the trace gas aspects of the project, secured a postdoctoral position at the University of Wisconsin-Madison working on nutrient cycling modeling and N fate. Undergraduate student Ada Fitz Axen did independent research on spinach production in the project's Experiment two and presented results at the University of Minnesota research symposium. Finally, at the University of MN and KSU, six additional undergraduates (UMN: Tanner Beckstrom, Martina (Mar) Horns, Kai Leung, Emily Locke, and Heidi Schlinsog; K-State: Cassidy Fleck and Jessica Mascote) learned basic field and lab techniques, introducing them to opportunities in scientific research. One high school student in KS, Luke Lebar, was also trained. While not financially supported by the project, two additional UMN undergraduates (Sara Duber and Lucia Carlson) and one Macalester College intern (Zala Cok), were exposed to the project via occasional fieldwork and project reports. Finally, the project provided training to 4 high school students of color from North Minneapolis during a 2d educational program to learn about high tunnel production in Madison, Wisconsin, in partnership with NC-SARE Youth Educator Grant YENC19-137, and Marcus Kar, Program Director of the Youth Farm urban youth development organization in Minneapolis/St. Paul. How have the results been disseminated to communities of interest?In Minnesota during the 2019-2020 reporting year, in-person outreach and visits to the experimental sites was hindered by covid-19, however one class (HORT 3131) and one organic field day allowed 60 participants, including both university students and the general public, to learn about our project via visits to our experimental sites.Despite the covid-19 restrictions, prior to cancellation of in-person events, we were able to present to live audiences at 12 educational events, including workshops, conference presentaions, and guest lectures. In Kansas, Co-PI Rivard was invited to present at three (virtual) conferences and one webinar on the topic of diversification of high tunnel rotations, including cover crop inclusion. In Kentucky and the Southeast, information about the project was disseminated to an audience of ~250 through field days and conference activities. In particular, at least 45 of these participants were Cooperative Extension Agents or other farm service providers and were exposed to the project in a train-the-trainer capacity. What do you plan to do during the next reporting period to accomplish the goals?Additional outreach efforts will be made to increase the number of responses to the soil health survey. Then, estimates will be incorporated into the enterprise budget analysis to consider the returns to cover cropping practices for various lengths of time. During the final no-cost extension year, we will finish all lab assays. Data analysis has begun and will be completed and compiled in peer-reviewed publications, including six planned for the biophysical data (soils, plants) and two for the economic analysis. We have presented one of the three NRCS Organic webinars. The final two will be taught in the final project year.

Impacts
What was accomplished under these goals? High tunnel production has increased dramatically in the United States over the past decade, providing growers with new opportunities for high value production, both in novel crops as well as season extension. Many growers attempt to maximize the profits available in high tunnel crops through intensive cropping, often resulting in long-term soil degradation and environmental consequences. Farmers are interested in learning strategies to improve their high tunnel soil health without compromising their income. In research conducted through this project, summer and overwintering cover crops grown in high tunnels produced substantial amounts of biomass and, in the case of legumes, contributed nitrogen to the system through biological nitrogen fixation. Winter vetch cover crops were able to replace up to 77% of fertilizer N, with no decrease in crop yield relative to fully fertilized plot. Cover crops grown during the summer produced significant biomass and plant-based nitrogen to help reduce the application of external inputs, such as manure, known to contribute to environmental issues such as phosphorus overload in soils. Our results suggest that organic farmers using high tunnels have multiple options to fit a cover crop into their system. By providing growers with clear data about the soil health, crop yield, and economic considerations posed by cover cropping systems, farm systems can become more sustainable, limiting the need and expense for off-farm fertilizer, and reducing the detrimental impacts of overuse of fertilizer, especially phosphorus run-off and losses via GHG emissions. Goal 1: In year four of the project, covid-19 impacted our ability to conduct laboratory analysis, including PoxC, PLFA, and total CN analysis. We anticipate that by spring of 2021 all data will be finalized. We completed field trials for our cropping systems experiment, examining the trade-offs associated with the integration of a winter legume cover crop in rotation with tomatoes, with an emphasis on soil and crop quality, nutrient retention, and cost effectiveness. In this experiment we collected soil samples, weed and cover crop biomass, and produce yield data, as well as labor and other economic inputs to create a systems analysis. We also completed a second replicated field experiment, "planting windows" to identify cover crop species and planting date combinations that produce optimal nitrogen management during narrow windows of planting time in each of our three study regions. This experiment includes cover crop and weed biomass samples as soil samples focused more intensely on nitrogen cycling questions. Experiment 2 (cover crop windows) evaluated the potential of three cover crop scenarios in high tunnels, including rotations of warm season summer cover crops (cowpea and cowpea/sorghum sudangrass), winter-killed fall cover crops (millet, and millet/cowpea), and overwintered cover crops (vetch and vetch/rye). In Minnesota, cowpea/sorghum sudangrass treatment consistently produced the highest cover crop biomass (driven by sorghum sudangrass), followed by vetch/rye and cowpea treatments. Millet, millet/cowpea, and vetch treatments had low biomass. Cowpea plots appeared to positively impact available soil N in some regions three weeks after termination and biomass incorporation, with nitrate levels increasing in plots in Minnesota and in Kansas relative to the cowpea/sudangrass mix. Greenhouse gas emissions results indicate that trace gas flux patterns and cumulative total fluxes differ more by microclimate between the open field and inside tunnels than by practices within the high tunnels. For example, in MN, cumulative nitrous oxide (N2O) fluxes in the high tunnel cover crop treatments were twice that of the open field in 2017 and five times that of open field in 2019. Cumulative CO2 and N2O fluxes in the HT were numerically greater in the continuously cropped (IC) treatment compared to the cover crop (IR) treatment in both 2017 and 2019, but differences were not as pronounced as the open field. Cumulative N2O fluxes in the IC treatment was nearly three times that of IR in 2019. In KY, cumulative trace gas emissions were numerically greater in the HTs than the open field, likely due to high mineral N levels in the soil due to the management history and lack of leaching rainfall for multiple years. However, despite increased greenhouse gas emissions in some HT treatments during some years, yield-scaled global-warming potential (GWP) were lower in HT treatments than the open field in all treatment/site combinations. The GWP is a sustainable intensification measure which adjusts emissions with total crop yields, giving a measure of total emissions per unit yield. Lower yield- scaled GWP values were driven by higher yields in the HTs. Yield scaled GWP was nearly identical in the HT treatments in KY, and was ~40% less than in the open field, on average. Treatment differences were more pronounced in MN, where yield-scaled GWP was 400% greater in the open field than the vetch-based HT treatment in 2017 (open field data were not available for 2019, due to crop failure. Goal 2: A survey developed with a conjoint instrument was finalized after feedback from soil experts and the project advisory board members. The survey was distributed to participants at the 2020 Minnesota Organic Conference and MOSES Organic Farming Conference. Preliminary analysis suggests the survey instrument is effective in estimating values that farmers place on different improvements in soil health. An online version of the survey was designed and distributed to other channels, such as a contact list of farmers at the FairShare Farm and the Organic Broadcaster newspaper at the MOSES, to reach target sample size for reliable statistical analysis. Additional responses will be collected during the winter of 2020. In addition to soil and plant data, we compiled economic data for each cover cropping system, including labor inputs and material costs. Second and third year data were cleaned to account for differences in sampling and tested using an ANOVA to explore the statistical significance of treatment effects. A literature review of cover cropping economics was performed. With the statistical analysis and literature review complete, data from years 1-3 will be analyzed using a partial budget method to explore the economic impact of cover crop use. Results from the analysis will be submitted this winter to a peer-reviewed journal: Agroecology and Sustainable Food Systems or Renewable Agriculture and Food Systems. Goal 3: The literature on soil valuation and measurement of soil health has been reviewed to develop a valuation instrument. The valuation will be included in a longer survey to collect attitudes toward and current practices of soil nutrient management. An earlier version of the survey was reviewed by the advisory board members, and Peterson and a graduate student discussed the survey instrument with each member on the phone. The valuation instrument is continually revised in preparation for its administration. The plan for administration is to invite attendees of a soil health session at MOSES to participate in the survey. While covid-19 reduced the number of planned events, we were still able to bring results to an estimated 800 individuals, including both virtual and in-person events. The most impactful and high profile of these events was most likely the MOSES Organic University where we reached 60 organic farmers interested in high tunnel production. As part of this event, a 100-page book was developed that included all presentations, as well as numerous additional print resources on high tunnel management. Finally, as a team we updated the hightunnel.org website to include updated resources from multiple sources focusing on high tunnels generally, and more specifically high tunnel soil management.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Gieske, M. F., Grossman, J. M. , Pfeiffer, A., Shrestha, D., Al-Zubad, A., Li, F., Rivard, C. L., Jacobsen, K., Gutknecht, J. L., ASA-CSSA-SSSA International Annual Meeting, "Cover Crop Effects on Soil Health in Organic High Tunnels," San Antonio, Texas. (November 12, 2019).
  • Type: Theses/Dissertations Status: Published Year Published: 2020 Citation: Skinner, A., 2020. Integrating cover crops in high tunnel production systems. M.S. Thesis. Kansas State University. https://krex.k-state.edu/dspace/handle/2097/40667
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Rivard, C. Ft. Walton Beach, FL ⿿Breaking Bad Habits: Integrating Crop Diversity into High Tunnel Production Systems⿝ Panhandle Fruit and Vegetable Conference, October 2, 2019.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Rivard, C. ⿿Breaking Bad Habits: Integrating Crop Diversity into High Tunnel Production Systems⿝ Missouri Winter Vegetable Production Conference, Feb 17, 2020, Eureka, MO
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Rivard, C. ⿿Breaking Bad Habits: Integrating Crop Diversity into High Tunnel Production Systems⿝. Mid-Atlantic Fruit and Vegetable Conference, January 29, 2020, Hershey, PA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Fitz-Axen, A., Gieske, M., and Grossman, J. 2020. ⿿The Effects of Cover Crops on Vegetable Yield and Mineral Nitrogen in High Tunnel Agricultural Systems⿝. UMN Undergraduate Research Symposium. Virtual Presentation accessed at Ada Fitz Axen.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Locke, E., Gieske, M., Gutknecht, J., and Grossman, J. 2020. ⿿Evaluating Enzyme Activity in Agricultural High Tunnels Compared to Open Fields in Minnesota and Kentucky⿝. UMN Undergraduate Research Symposium. Virtual Presentation accessed at Emily Locke.


Progress 09/01/18 to 08/31/19

Outputs
Target Audience:In year 3 of the project, research results and related resources have been shared with a wide variety of grower groups and students, including Appalachian, Hmong, refugee, indigenous and urban farmers, as well as NRCS and Extension professionals serving these audiences. An experiential learning trip in May-June, 2019 provided an opportunity for ten students from three states to learn more about historical and current challenges and opportunities for sustainable agriculture in Appalachia. Learning opportunities included site visits to several sites of historical or commercial importance, and a hands-on high tunnel build with Grow Appalachia, a local NGO working to promote sustainable agriculture in the region. Every student responding to our post-trip survey reported increased knowledge of Appalachian agriculture, challenges to food access and food security, and high tunnel construction and management. Student comments included: "I gained so much perspective on Appalachian food systems and on how the general public understands food systems." "I really want to work in food systems now. Preferably urban food systems like the hub we saw in Lexington which incorporated food, community, and education." "I brought ideas and inspirations back to our college farm in hopes of broadening our horizons while simultaneously refining some of our goals. Many ideas and experiences are still ruminating as inspiration that will be utilized as I pursue a career in nonprofits that work with agriculture." Experimental results were also shared via an invited presentation at the Emerging Farmer's Conference (formerly the Immigrant & Minority Farmers Conference), which serves to advance the success and sustainability of farmers who traditionally face barriers to the education and resources necessary to build profitable agricultural businesses, including immigrant farmers and farmers of color. In addition, invited talks were given on the project at the Soil Science Society of America annual meetings in San Diego (2018), the MN Organic Conference in St. Cloud, MN (Jan 2018), the Sustainable Farming Association Conference in St. Joseph, MN (March, 2018) and the Bimaaji'idiwin Gitigaan, a farmer training program on the Fond du Lac reservation (April, 2019). In Kansas, results of the project were delivered to the Juniper Gardens Refugee Training Farm (Kansas City, KS) both formally and informally. Co-PI Rivard collaborated with Juniper Gardens Training Farm Program Manager, Semra Fetahovic, to plant a demonstrational cover crop on their farm. Ms. Fetahovic was given teaching materials and delivered formal instruction on soil health and cover cropping practices to refugee farmers. Ms. Fetahovic also participated in the experiential learning trip in Kentucky, which will lead to further medium- and long-term impacts as a result of the project. The work of the project was also delivered during three field days, two workshops, three regional growers' conferences, and numerous tours and other training events in Kansas. Direct results from the project were delivered to Growing Growers Kansas City Farm apprentices during the soils workshop and vegetable research field day. Growing Growers KC is a beginning farmer apprenticeship program that utilizes workshops and apprenticeships at local organic farms (growinggrowers.org). In Kentucky, results of the project were directly delivered to Kentucky specialty crop producers via two field days at the University Horticulture Research Farm in Lexington, Kentucky. These included tours of the field experiments and discussion of the app being developed by the project, which producers were keen to learn more about. The Organic Association of Kentucky (sponsor of one of the field days) has committed to help disseminate the app once it is finalized. A total of ~12 UK Cooperative Extension agents were also reached through these trainings. A demonstration of summer cover crops for high tunnels demonstrated cover crop timing strategies at a demonstration site at The Healing Place in Louisville, Kentucky. This was requested by the local Soil and Water Conservation District and the county Cooperative Extension Horticulture agent who were familiar with the project. The Healing Place is a women's residential drug and alcohol recovery treatment center with a horticulture therapy program. The women in the program directly participated in the workshop and helped select the cover crops, seeded them, and initiated a vibrant discussion about the parallels between soil recovery and human recovery. Producers throughout the Southeastern US were exposed to the project through a session on Organic Soil Management of High Tunnels at the Southern Sustainable Agriculture Working Group Annual Conference in Little Rock, Arkansas. Undergraduate students in the UK College of Agriculture, Food and Environment were reached through field and lab activities associated with the Sustainable Agriculture Undergraduate Degree Program. Changes/Problems: Describe major changes/problems in approach and reason(s) for these major changes. If applicable, provide special and/or additional reporting requirements specified in the award Terms and Conditions. Major changes include: major problems or delays that may have a significant impact on the rate of expenditure; significant deviations from research schedule or goals; unexpected outcomes; or changes in approved protocols for the use or care of animals, human subjects, and/or biohazards encountered during the reporting period. The winter vetch in the cropping systems experiment did not survive the 2017-2018 winter in MN, thus we will continue this experiment one additional year to complete three full years of data collection. Due to crop failures at the MN location during year 2 and data collection complications at the MN and KS locations during years 2 and 3, economic and soils data collection took longer than anticipated. Weekly calls were scheduled with team members to ensure quality control with the incoming material, labor, and harvest records. The planting windows experiment was started in all three sites in the fall of 2017 but experienced setbacks in both MN and KY. This experiment will be continued in these two states through our no-cost extension year What opportunities for training and professional development has the project provided??During this reporting period, the project has supported professional development for one post-doctoral student, three graduate students (UMN, KY and KS), and seven undergraduate students (in addition to those supported last reporting period). Miriam Gieske, post-doctoral researcher at the University of MN, has learned project management skills, and advanced her knowledge of soil assays and high tunnel field management. Ashlee Skinner, Master's student at Kansas State University, has conducted her M.S. degree work on this project and is currently writing up results. Through her work on this project, Ashlee has gained experience developing, collecting and implementing research protocols related to soil health in high tunnels. Dojin Park, in PhD student in Applied Economics at Minnesota, learned a great amount about Midwestern US agricultural systems through his research to better understand what farmers value about soil. Ammar Al-Zubade, a PhD student in the Integrated Plant and Soil Science Program at the University of Kentucky learned how to collect greenhouse gas data and more about soil processes in organic specialty crop production systems. Undergraduate students Ada Fitz Axen and Harywilliam Gonzalez both conducted mentored research in the experiment in Minnesota. Finally, at the University of MN and Kansas State, seven additional undergraduates (UMN: Christine Evitch - a non-traditional student returning to college, Natalie Duncan, Kai Leung, Emily Locke, and Heidi Schlinsog; K-State: Cassidy Fleck and Jessica Mascote) learned basic field and lab techniques, introducing them to opportunities in scientific research. Ten participants from three states learned about high tunnel building techniques and Appalachian agriculture and food systems through a weeklong experiential learning trip in May-June 2019. These participants included graduate student Ashlee Skinner from Kansas State, post-doctoral student Debendra Shrestha from University of Kentucky, Semra Fetahovic of Juniper Gardens Training Farm in Kansas City, Kentucky farmer Patrick Ranval, and six additional undergraduate and graduate students from K-State, UKY, and UMN How have the results been disseminated to communities of interest??Preliminary results have been shared through a number of field days, conference presentations, and workshops (see "Other Products" section for detailed list). In summary, extensive outreach in each of the three states has reached hundreds of growers and resulted in tangible changes in growing practices. In Minnesota, over 150 visitors to our high tunnel experiment on the University of Minnesota flagship Twin Cities campus learned about cover crop options for high tunnels by visiting the experiment. In Kansas, information about the research and project need was disseminated to an audience of at least 700 through field days, tours, and other educational events. In addition, the results of the project were delivered to at least 500 farmers through extension trainings, conferences, webinars, and workshops. Refugee farmers at the Juniper Training Farm (Kansas City, KS) acquired knowledge related to cover crop selection and management. Following training provided through this project, farmers at the Juniper Training Farm (Kansas City, KS) planted cover crops at their field in order to demonstrate and evaluate the use of soil health building practices. Kansas project staff have also noted an increase in area growers asking extension staff for cover crop recommendations for high tunnel production and an increase in grower concern about soil health, as evidenced by more growers asking how to proactively maintain good soil health. In Kentucky, information about the project was disseminated to an audience of ~200 through field days and educational activities. In particular, at least 15 of these participants were Cooperative Extension Agents or other farm service providers and were exposed to the project in a train-the-trainer capacity. Following training provided by the project, residents and supporting technical service providers at The Healing Place (Louisville, KY) planted cover crops in their high tunnel to address compaction and organic matter management issues and incorporate soil restoration into their horticulture therapy program. What do you plan to do during the next reporting period to accomplish the goals??During the next year, field work will continue in Minnesota for the cropping systems experiment. The cover crop windows experiment will continue in all three states until data collection is finished next summer. Soil and biomass samples will continue to be analyzed in the lab setting in Minnesota, allowing us to ensure a standardized analysis approach. We will finalize the development of educational materials that will be made available to other educators via online resources and slide sets. Training of NRCS personnel in high tunnel management will take place via a series of three webinars presenting our results from the project. A phone-based app to assist growers and students in understanding cover crop nitrogen credits and improving on-farm decision making has been developed and will be put to use in our outreach efforts to the degree possible. We have been granted a no-cost extension year to finalize data collection in some states (see Changes/Problems

Impacts
What was accomplished under these goals? High tunnel production has increased dramatically in the United States over the past decade, providing growers with new opportunities for high value production, both in novel crops as well as season extension. Many growers attempt to maximize the profits available in high tunnel crops through intensive cropping, often resulting in long-term soil degradation and environmental consequences. Farmers are interested in learning strategies to improve their high tunnel soil health without compromising their income. In research conducted through this project, summer and overwintering cover crops grown in high tunnels produced substantial amounts of biomass and, in the case of legumes, contributed nitrogen to the system through biological nitrogen fixation. Winter vetch cover crops were able to replace up to 77% of fertilizer N in high tunnels, with no significant difference in cash crop yield relative to fully fertilized plots. Our results suggest that organic farmers using high tunnels have multiple options to fit a cover crop into their system. By providing growers with clear data about the soil health, crop yield, and economic considerations posed by cover cropping systems, farm systems can become more sustainable, limiting the need and expense for off-farm fertilizer, and reducing the detrimental impacts of overuse of fertilizer, especially phosphorus run-off. Goal 1: In year three of the project, we continued field trials for our cropping systems experiment, examining the trade-offs associated with the integration of a winter legume cover crop in rotation with tomatoes, with an emphasis on soil and crop quality, nutrient retention, and cost effectiveness. In this experiment we are collecting soil samples, weed and cover crop biomass, and produce yield data, as well as labor and other economic inputs to create a systems analysis. We have completed most data collection and preliminary analysis for cover crop biomass production, carbon and nitrogen cycling, and economic outcomes. We also continued a second replicated field experiment, "planting windows" to identify cover crop species and planting date combinations that produce optimal nitrogen management during narrow windows of planting time in each of our three study regions. This experiment includes cover crop and weed biomass samples as soil samples focused more intensely on nitrogen cycling questions than the cropping systems experiment. Experiment 1 (cropping systems) outcomes show that winter vetch cover crops were able to replace up to 77% of fertilizer nitrogen in high tunnels. In addition, vetch cover crops sometimes reduced soil mineral nitrogen in fall and early spring, when tomatoes were not growing, reducing the potential for nitrogen losses. Yields were similar between plots with and without cover crops, suggesting cover crops replaced fertilizer adequately. However, the cover crops did not increase permanganate-oxidizable carbon, a measure of carbon available for microbes to use. Regarding gaseous loss of nitrogen or organic carbon in the forms of nitrous oxide or carbon dioxide, results from 2017 and 2019 in Minnesota demonstrate that cover crops do not change the levels of gaseous losses, but that any high tunnel system has lower emissions than field best practices systems. In Kentucky however, cover cropping resulted in higher gaseous losses than either non cover cropped high tunnels or field best management practices treatments. Experiment 2 (planting windows) outcomes: In Minnesota, cover crop biomass ranged from 371 kg ha-1 for a fall-seeded mix of frost-sensitive Japanese millet and cowpea, to 8622 kg ha-1 for a mix of cowpea and sorghum-sudangrass grown in summer, with overwintering vetch and vetch-rye mix cover crops producing intermediate amounts of biomass. Cowpea grown in summer and vetch grown in winter contributed similar amounts of fixed nitrogen. In the summer and overwintering windows, grass-legume mixes produced more total biomass than legumes grown alone. However, legumes contributed more fixed nitrogen to the system when grown alone than when grown in mixes with grasses. Despite these differences, soil mineral nitrogen did not vary significantly between treatments with legumes alone and those with legume-grass mixes. Analysis of biomass and nitrate results for Kansas and Kentucky is in progress. Lab analysis of microbial biomass and other characteristics of the soil microbial community is underway for samples collected in 2018 and 2019. Goal 2: In addition to soil and plant data, we also collected economic data relative to each cover cropping system, including labor inputs and material costs associated with this system. First year data was analyzed using a partial budget approach to better understand the economic impact of cover crop use in HT systems. Data from years 2 and 3 will be analyzed once final harvest data is compiled by the field teams. Considerable time was spent during the spring and summer of 2019 compiling and cleaning data from all sites. Net returns from the vetch rotation and non-vetch control treatments as well as the net change in income owing to cover crop treatments will be calculated this winter after final harvest data has been compiled by the field teams. Material costs recorded included seed, inoculants, low tunnel materials, fuel, water, and interest on operating expenses. Labor costs included time spent on tillage and bed prep, planting, irrigation set up and repairs, watering, ventilation and monitoring, low tunnel install and crop termination. Spinach enterprise costs were collected for KS and KY (per original experiment design). Summary statistics and discussion of results: Data from years 2-3 will be analyzed once final harvest yields for tomatoes have been tabulated. Analysis will utilize partial budgets as was done for year 1 to explore whether the added costs associated with the use of cover crops can be offset by positive changes in yield (income) for the tomato enterprise. The literature on soil valuation and measurement of soil health has been reviewed to develop a valuation instrument. The valuation will be included in a longer survey to collect attitudes toward and current practices of soil nutrient management. An earlier version of the survey was reviewed by the advisory board members, and Peterson and a graduate student discussed the survey instrument with each member on the phone. The valuation instrument is continually revised in preparation for its administration. The plan for administration is to invite attendees of a soil health session at MOSES to participate in the survey. Goal 3: As the project comes nearer the conclusion of field experimentation work, outreach and education opportunities for both students and growers have increased. A highlight of year three was the development and execution of an integrated one-week experiential learning field course in conjunction with the NGO Grow Appalachia for students to learn about HT production in under-resourced regions of the U.S. such as Appalachia. In addition, the project team has nearly completed development of a mobile application tool for classroom and outreach events to aid farmers in their decision making regarding cover crop planting dates, biomass accumulation and N delivery in HT's, as well as other cover crop planting scenarios, as well as the creation of a collection of classroom and outreach teaching modules and additional resources to be posted on HighTunnels.org. These materials and project findings in general have been disseminated via a wide range of outlets, with an emphasis on underserved target audiences

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Li, F. (Author & Presenter), Grossman, J., Pfeiffer, A., Gieske, M., Rivard, C., Jacobson, K., Agronomy Society of America Annual Meeting, "Legume Cover Crop Effects on Tomato Yield and Soil Health in Organically Managed High Tunnels," Baltimore. (November 5, 2018).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Grossman, J. M. , Wauters, V., Soil Science Society of America Symposium on Multifunctional Agriculture, "Designing multifunctional agricultural systems via legume diversification in the Upper Midwest," San Diego, California. (January 7, 2019).
  • Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2019 Citation: A. Skinner, R.A. Cloyd, D. Presley, and C.L. Rivard. 2019. Impact of cover crops on soil arthropods in high tunnel systems. American Society of Horticulture Science 24 July, 2019. Las Vegas, NV. (oral presentation). Hortscience (in press)
  • Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2019 Citation: C.L. Rivard. 2019. Integrating cover crops successfully into high tunnel production systems. American Society of Horticulture Science 25 July, 2019. Las Vegas, NV. (Invited High Tunnel Discussion Panel). Hortscience (in press)
  • Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2019 Citation: S. Han, L. Hok, L. Chea and C.L. Rivard. 2019. Effects of living mulches and soil nutrient management on growth, yield, and yield components of Chili pepper (Capsicum annum L.). American Society of Horticulture Science 24 July, 2019. Las Vegas, NV. (poster). Hortscience (in press)


Progress 09/01/17 to 08/31/18

Outputs
Target Audience:In year 2 of work, we have begun to share preliminary results with grower groups and other stakeholders in a variety of extension programs and professional meetings. Audiences for these programs have been comprised of Appalachian, Hmong, urban, and refugee farmers as well as NRCS and Extension professionals serving these audiences. We have continued ongoing communication with our 9-member Grower Advisory Board including individuals and organizations representing Appalachian, Hmong, urban, and refugee farmers. The Advisory Board has provided critical input into fine-tuning research questions and methodologies and outreach strategies. Changes/Problems:The winter vetch in the cropping systems experiment did not survive the 2017-2018 winter in MN. Since there was effectively no winter cover crop treatment, we reduced our sampling schedule, collecting only spring and fall soil samples. Pending approval for a no-cost extension, we will continue this experiment one addition year to complete three full years of data collection. The planting windows experiment was started in all three sites in the fall of 2017 but experienced setbacks in both MN and KY. In MN, fall planted cover crops had poor germination and minimal winter survival, presumably due to both poor soil quality as well as harsh winter conditions. Topsoil and compost material was added to the MN high tunnel in the spring of 2018, creating a new effective start date for experiment 2. The KY site experienced severe wind storms in April 2018 made the tunnels unsafe for human entry and required significant repair work, resulting in postponement of the experiment until fall of 2018. Pending approval for a no-cost extension, we will continue this experiment one addition year to complete two full years of data collection. What opportunities for training and professional development has the project provided?During this reporting period, the project has supported professional development for 2 post-doctoral students, 1 graduate student and 2 undergraduate students. Post-doctoral students Fucui Li and Miriam Gieske, both post-doctoral students at the University of MN, have learned field experiment management skills as well as soil health lab assays. Ashlee Skinner is a Master's student at Kansas State University. Through her work on this project, Ashlee has gained experience developing, collecting and implementing research protocols related to soil health in high tunnels. Ashlee has been successful at teaching these skills to growers as well as K-12 audiences during extension and outreach activities that happen at KSU OHREC. In the summer of 2018, Ashlee attended ASHS to learn more about research methods that are used in horticulture. While there, she also attended an Urban Food Systems Study Tour of Hawaii (not supported by project) to learn about sustainable agriculture methods utilized and food security issues surrounding Urban Agriculture. Undergraduate students Daniel Lee and Natalie Duncan were both employed at the University of MN and learned basic field and lab techniques, introducing them to opportunities in scientific research. How have the results been disseminated to communities of interest?Preliminary results have been shared through a number of field days, conference presentations, and workshops (see "Other Products" section for detailed list. In addition to the activities listed above, information from this project has contributed to these other grant-funded projects: Soil Health Bootcamp Workshop held at Schmidt Farms (SARE PDP) Soil Health Bootcamp Workshop held at R&B Produce Farm. Ft. Scott, KS (SARE PDP) J. French, T. Buller, K.Oxley, and C.L. Rivard. 201X. Growing Under Cover: A Kansas Grower's Guide. (Volume 3) Kansas Rural Center Publication (40 page manual) (KDA SCBG) J. Vipham, J. DeRouchey, C. Rivard, G. Sampson , and Z. Stewart. 2017 Multidimensional Trade-off Analysis of Integrated Animal-Horticulture Farming Systems for Improved Smallholder Farmer Adoption. (USAID) What do you plan to do during the next reporting period to accomplish the goals?During the next year, field work will continue for both the cropping systems and cropping windows experiemnts, including economic and agronomic data collection. Soil and biomass samples will continue to be analyzed in the lab setting. We have also begun preparing for an experiential learning trip in the summer of 2019 that will bring a dozen undergraduate and graduate students to the Hindman Settlement School, a cultural heritage center in Central Appalachia and other sites of agricultural and cultural importance in Appalachia as well as offer students a chance to engage in a low-tunnel building process with Appalachian growers. The development of a phone-based app to assit growers and students in understanding cover crop nitrogen credits and improving on-farm decision making is in progress and will be a focus project for the coming year.

Impacts
What was accomplished under these goals? High tunnel production has increased dramatically in the United States over the past decade, providing growers with new opportunities for high value production, both in novel crops as well as season extension. Many growers attempt to maximize the profits available in high tunnel crops through intensive cropping, often resulting in long-term soil degradation and environmental consequences. This work is intended to benefit growers who use high tunnels, or who are considering adding a high tunnel to their operation. Soil health data from the field experiments as well as the economic analysis is intended to provide growers with the resources they need to effectively weigh the costs and benefits of integrating soil building practices into their high tunnel rotation. By providing growers with clear data about the soil health, crop yield, and economic considerations posed by cover cropping systems, farm systems can become more sustainable, limiting the need and expense for off-farm fertilizer, and reducing the detrimental impacts of overuse of fertilizer, especially phosphorus run-off. In year two of the project, we continued field trials for our cropping systems experiment, examining the trade-offs associated with the integration of a legume cover crop in the rotation with tomatoes, with an emphasis on soil and crop quality, nutrient retention, and cost effectiveness. In this experiment we are collecting soil samples, weed and cover crop biomass, and produce yield data, as well as labor and other economic inputs to create a systems analysis. We have completed most lab work and preliminary analysis for the first year of data including both agronomic as well as economic data. We also initiated a second replicated field experiment, "planting windows" to identify cover crop species and planting date combinations that produce optimal nitrogen management during narrow windows of planting time in each of our three study regions. This experiment includes cover crop and weed biomass samples as soil samples focused more intensely on nitrogen cycling questions than the cropping systems experiment. Experiment 1 (cropping systems) outcomes In Kansas, both total tomato yield and marketable yield were significantly lower in the Integrated Rotation plots with a vetch cover crop than in the Intensive Control plots. Yield data are not yet available from Kentucky. In Minnesota, the vetch cover crop failed, and thus the effect of cover crops on tomato yield could not be tested. Experiment 2 (planting windows) outcomes In Minnesota, total cover crop biomass was greater in the cowpea/sorghum-sudangrass treatment than in the cowpea treatment, though this difference was only marginally significant. Cowpea biomass was significantly lower in the cowpea/sorghum-sudangrass treatment than in the cowpea treatment. Weed biomass did not differ significantly between treatments. Cover crop biomass data are not yet available from Kansas, and Experiment 2 had to be restarted in Kentucky due to high tunnel structural damage from a storm. Lab analysis of microbial biomass, potentially mineralizable N, and other characteristics of the soil microbial community is underway for all experiment 1 and 2 samples collected in 2018. In addition to soil and plant data, we also collected economic data relative to each cover cropping system, including labor inputs and material costs associated with this system. First year data was analyzed using a partial budget approach to better understand the economic impact of cover crop use in HT systems. 3(a) Major activities completed/experiments conducted: Enterprise data (yield, material input expenses, labor costs) was compiled at each site for year two of the experiment. Net returns were calculated for tomatoes produced using IR and IC treatments using year one data. Net change in income for the cover-tomato and spinach-tomato rotations was calculated to determine the net economic contribution of cover crop treatment using year one data. 3(b) Data collected: Material and labor costs were collected and compiled for cover crops and tomatoes at all three experiment locations. Material costs included seed, inoculants, low tunnel materials, fuel, water, and interest on operating expenses. Labor costs included time spent on tillage and bed prep, planting, irrigation set up and repairs, watering, ventilation and monitoring, low tunnel install and crop termination. Spinach enterprise costs were collected for KS and KY (per original experiment design). 3(c) Summary statistics and discussion of results: Preliminary results suggest no positive economic impact from the use of cover crops. Tomato yields, representing a change in income, show no significant change (positive or negative) following the use of cover crops in the IR treatment. Similarly, the use of cover crops resulted in a very modest reduction in applied nitrogen (due to nitrogen credit observed from cover crop). Therefore, with very little to no added income (tomato yields) or reduced expenses (applied nitrogen), we observed no offset in material and labor costs for the cover crop in year one of the experiment.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Jacobsen, K. L., MOSES Organic Farming Conference, "Soil Health in High Tunnels," Midwest Organic and Sustainable Education Service, Invited. La Crosse, WI, United States. (February 24, 2018). (No published citation, slides available upon request to confirm acknowledgement of NIFA support.)


Progress 09/01/16 to 08/31/17

Outputs
Target Audience:Our activities to date have centered on research that will meet the needs of high tunnel growers, especially limited-resource farmers. High tunnels can provide a sizeable market advantage to growers but must be managed well for soil health in order to remain productive over the long term. The opportunity for high return on high tunnel crops encourages growers to use intensive rotations and may limit opportunities for soil building, especially the use of cover crops. In keeping with the timeline set forth in our original proposal, we will not begin outreach and education activities until later years of the project. We have, however, been mindful about designing research with these growers in mind. We have established a grower advisory board comprised of nine growers or representatives of grower organizations from each of the three regions covered by this project. The Grower Advisory Board includes individuals and organizations representing Appalachian, Hmong, urban, and refugee farmers. Growers have advised project researchers regarding cover crop selection, research needs, and seasonal planting windows during which they are likely to plant cover crops Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?To date, this project has supported professional development for one post-doctoral student and one Master's student engaged in conducting field and lab research. Fucui Li has increased her knowledge of field approaches used in organic production through seminars and workshops, and also learned new field and laboratory protocols. Jennifer Nicklay is a Master's student at the University of MN in the Department of Soil, Water, and Climate. She has learned field and laboratory research methods and has carried out the soil gas sampling. We also trained an undergraduate student, Justin Panka, who is pursuing an undergraduate degree in Environmental Engineering at the University of Minnesota. Justin learned soil sample preparation and laboratory analyses including quantification of Permanganate oxidizable C (POX-C), Particulate organic matter (POM), and rhizobia occupancy from sampled soil. How have the results been disseminated to communities of interest?The Grower Advisory Board was established and had one full meeting. Individual growers have been consulted to provide input about experimental design related to their personal expertise. Involving this group in the early stages of our research has allowed us to design research that will meet real world needs of growers and provide results that are relevant to their operations. Early in our project two of the PI's (Jacobson and Grossman) delivered an NRCS webinar to over 375 live audience members discussing the project objectives. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? High tunnel production has increased dramatically in the United States over the past decade, providing growers with new opportunities for high value production, both in novel crops as well as season extension. Many growers attempt to maximize the profits available in high tunnel crops through intensive cropping, often resulting in long-term soil degradation and environmental consequences. This work is intended to benefit growers who use high tunnels, or who are considering adding a high tunnel to their operation. Data from the field experiments as well as the economic analysis is intended to provide growers with the resources they need to effectively weigh the costs and benefits of integrating soil building practices into their high tunnel rotation. In the first year, the high tunnel (HT) treatments significantly increased the tomato yield and quality, compared with the field best practice (FBP) in MN and KY. In the HTs, tomato yield and quality showed no significant differences between the integrated rotation (IR) and integrated control (IC) treatments in all three experimental sites (MN, KS, and KY). For the cover crop biomass, there was more weed pressure in the HT treatments than in the field in KY. In addition to tomato yield and cover crop biomass measurements, various parameters of soil N and C have been measured to better understand the nutrient cycling under each system for each site at different times. Abiotic measurements include permanganate oxidizable carbon (POX-C), potentially mineralizable nitrogen (PMN), which includes KCl extractable N pools (Ext-N). The results showed that the IR treatment with legume cover crops increased soil POX-C compared with IC treatment at the cover crop termination in KY. Compared with the IC treatment, the IR treatment decreased soil PMN at two weeks after the cover crop termination in MN and four weeks after the cover crop termination in KS, but the IR treatment tended to increase the Ext-N between two and four weeks after cover crop termination at all three sites. Microbial biomass growth and activity strongly mediates nutrients cycling in soils and either builds or degrades soil health. Therefore microbial biomass C and N were also measured . The microbial biomass C and N showed no significant difference between the treatments in three sites in the first year. In addition to soil and plant data, we also collected economic data relative to each cover cropping system, including labor inputs and material costs associated with this system. In the coming year we will analyze this data and build cost benefit models that growers can use to evaluate implementation on their own farms. During this first year of the project, we have developed our experimental design and research protocol. We have now finished collecting data from the first year of the experiment and will analyze this data in the coming months.

Publications