Source: UNIVERSITY OF FLORIDA submitted to
ENHANCING SUSTAINABILITY THROUGH INTEGRATED NUTRIENT MANAGEMENT IN CONVENTIONAL AND CERTIFIED ORGANIC VEGETABLE PRODUCTION SYSTEMS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0209689
Grant No.
(N/A)
Project No.
FLA-HOS-04601
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2006
Project End Date
Sep 30, 2011
Grant Year
(N/A)
Project Director
Treadwell, D.
Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611
Performing Department
Horticultural Science
Non Technical Summary
Florida's population is expected to reach 25 million by 2025 (Keen, 2006) and during the past year, agricultural land prices have increased by 50-88% across the state (Reynolds et al., 2006). Of the 44,000 farms in Florida, approximately 85% are less than 180 acres, and 75% of those farms have earnings of less than 25,000 dollars a year (USDA NASS, 2003). All farms in Florida face increasing pressure to manage water resources more effectively. Nationally, agriculture accounts for 80% of the nation's consumptive water use. Florida's Department of Agriculture and Consumer Services initiated Best Management Practices (BMPs) (FLDACS, 2005) to reduce excessive nutrient loads of nitrogen (N) and phosphorus (P) into surface and groundwater (FDEP, 2004). N and P soil applications may be regulated in the future if sufficient progress to water quality is not made. The primary goal of the Sustainable and Organic Vegetable Production Program at the University of Florida is to minimize the negative environmental impacts of nutrient management in vegetable systems while ensuring long term security of local farming systems. Despite the ongoing application of organic soil amendments in cropping systems, there is an acute need for information and technologies to plan and monitor nutrient management programs using plant and animal fertility sources. No studies have been conducted to elucidate the rate and amount of plant available nutrients as influenced by management, soil type and climate from cover crops in subtropical conditions.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1011499101010%
1021499101015%
1021599101015%
1025210101015%
1027299101025%
1111499101010%
1331499101010%
Knowledge Area
133 - Pollution Prevention and Mitigation; 102 - Soil, Plant, Water, Nutrient Relationships; 111 - Conservation and Efficient Use of Water; 101 - Appraisal of Soil Resources;

Subject Of Investigation
1599 - Grain crops, general/other; 5210 - Fertilizers; 1499 - Vegetables, general/other; 7299 - Research equipment and methods, general/other;

Field Of Science
1010 - Nutrition and metabolism;
Goals / Objectives
Objectives 1. Assess nutrient release patterns of common organic soil amendments (OSA) in controlled environments to increase our knowledge of factors governing rate of nutrient release and to facilitate field-level nutrient management. 2. Increase adoption of cover crops in Florida vegetable cropping systems by identifying species and varieties suitable to subtropical conditions and optimizing their management to improve nutrient cycling 3. Develop novel management strategies in vegetable cropping systems that optimize nutrient utilization from OSA while reducing risk to soil and water quality. 4. Form a multidisciplinary stakeholder advisory board whose mission will be to develop intellectual and financial infrastructure to reduce or eliminate barriers to agricultural sustainability through collaborative long term farming systems research and community outreach.
Project Methods
Objective 1. Nutrient release curves (content over time) of common organic substrates will be constructed to best synchronize application rates with crop nutrient demand. Total, inorganic and organic fractions of carbon and crop nutrients from soil or media will be analyzed according to standard laboratory methods (SSSA, 1996). When plant residues are used, additional data will be collected on residue quality including % lignin (acid detergent fiber; Anderson and Ingram, 1993) and soluble polyphenol content. Samples will be processed with a CHN Analyzer (Leco Corporation, St. Joseph, MI), submitted to ETSL (UF soil testing facility) or performed in the laboratory. Organic resource quality, decomposition kenetics, and nutrient release patterns will be determined with appropriate statistical models. Objective 2. Cover crop planting depth, seeding rate, starter fertility needs and seasonal management (eg. mowing at a particular physiological growth stage) will be examined systematically. Method and timing of kill and residue management will be addressed thoroughly for subtropical conditions. Plant physiological parameters such as N and carbohydrate translocations, leaf area index, dry weight, lignon and polyphenol content during development will be monitored as they are affected by carefully and consistently monitored environmental factors. Soil moisture tension monitors and soil temperature probes will be used. These data will be regressed over qualitative and quantitative treatment data mentioned above. Objective 3. Based on knowledge gained on organic amendments from trials in Objectives 1 and 2, the next steps to optimize nutrient management include: a) match sampling and data analysis techniques to typical climatic and soil properties of a region b) explore the interactions of families of amendments (compost/soluble certified organic fertilizers/animal wastes/cover crops) with soil types and regional climates, c) elucidate the effect of irrigation on the movement of nitrogen and other nutrients through the production bed and soil profile d) utilize experimental designs, statistical models and analysis to validate prediction models for nutrients in these systems. Whenever possible, additional research from other disciplines such as soil science, entomology, nematology, pathology, and soil microbiology will be included to study effects of nutrient management on other factors important to production. Objective 4. A multidisciplinary stakeholder advisory board will be formed for the purpose of strengthening relationships, identifying critical research needs and securing long term funding for long term farming systems research. A long term farming systems trial will provide critical information on the effects of OSA to soil, water and crop quality over time. Management will be representative of typical practices and commodities in our area. Although the experimental design will be determined by the advisory board and funding constraints, the idea is to establish water quality monitoring devices on a small farm-scale to represent producer conditions as much as possible.

Progress 10/01/06 to 09/30/11

Outputs
Target Audience:From the period 2006-2011, the target audience remained consistent and included Extension faculty and staff and other technical service providers, industry partners, agency personnel and farmers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Concepts and strategies of environmental (nutrient and cover crop management), economic (farm diversification and season extension) and social sustainability (capacity-building) to Extension faculty, industry partners, and producers were disseminated as follows: Nutrient and Cover Crop Management. Improved practices are of great interest to farmers who desire to reduce off-farm inputs and reduce risk to water quality. Producers are interested in satisfying USDA-Natural Resource and Conservation Service (NRCS) incentive programs, check-off standards for Florida's Best Management Practices (BMP) program, and National Organic standards. Educational programs included: Field days with demonstrations at PSREU in Citra and NFREC in Live Oak. Six state and eleven county extension presentations delivered to 572 producers and county faculty, and 5 presentations to 150 Master Gardeners In-service trainings (IST): 1) Whether you like it or not! Tools for success in the BMP Era, 2) Nutrient Management Updates for Agronomic Crops, and 3) Workshop on BMP Research and Extension Priorities for Horticultural Crops Total attendance 187 agents and technical service providers. I regularly contribute to state-wide planning and implementation of educational programs with the Fruit and Vegetable Commodity Team, including participation at retreats, in-service trainings and in ad-hoc committees. Diversifying farm enterprises and extending the season to sell during "non-peak" production times reduces financial risk and extends cash flow. Understanding consumer preferences helps producers choose enterprises that consumers want and are willing to pay for. Constructed a greenhouse in Homestead for extension programming on season extension and crop diversification. Conducted heirloom tomato variety trial in Live Oak under field and shade house conditions and published in a proceedings paper. Eight presentations on heirloom vegetable production, marketing trends, and strategies to improve direct sales were given to farmers and agents. One IFAS Presentation on heirlooms was published with Alachua County Extension agent. Evaluated and identified farm planning software suitable for small farmers to help maximize crop diversity and extend cash flow with two Florida farmers: Farming Systems, Inc. and Bee Heaven Farm. Educate experienced and beginning producers interested in adopting organic practices compliant with the USDA National Organic Program and introduce them to the state, national and international organic industry. Principle investigator for internally-funded program "Educational Materials for Organic Vegetable Producers" in collaboration with IFAS Communications, 15 UF-IFAS faculty and one organic producer. This award produced: 13 EDIS publications (4 Treadwell lead) 9 Virtual Field Day segments produced with IFAS Communications. These short educational video segments (5-17 minutes) are available on the UF-IFAS Virtual Field Day website along with supporting EDIS publications (http://vfd.ifas.ufl.edu). For the first time, a video segment was embedded into an EDIS document that demonstrates cover crop termination with a roller-crimper I designed and commissioned (http://edis.ifas.ufl.edu/HS389). Organic Farming Field Days, Workshops, and IST. Organized and implemented a statewide 2007 Organic Farming Field Day and Workshop at PSREU in Citra, FL in collaboration with Florida Organic Growers. Eleven UF-IFAS faculty and 7 certified organic growers prepared and delivered programs to over 230 producers, county faculty and industry stakeholders. Participated in 2009 Organic Farming Workshop, St. Croix, US Virgin Islands. Sponsored trip by the University of Virgin Islands to contribute to a two-day intensive workshop on cover crops and nutrient management in organic systems to 30 area farmers, extension professionals and research faculty in the Caribbean. In-service trainings: 1) Organic Crops Workshop and 2) Organic Myths vs. Realities - What Consumers Need to Know. Attendance was 79 UF web site development. Organized and contributed to a major revision of the Organic Farming topic area in the Small Farms and Alternative Enterprises website. The topic area continues to receive updates as needed, and as new content is published. Frequent reviewer for organic web content for other Departments, including SNRE and Environmental Horticulture. Master Gardener Training. Planned (with Sydney Park-Brown) and delivered a presentation on organic farming in a State-wide videoconference for Master Gardeners simulcast to 11 county Extension offices and viewed by 490 people. Five additional trainings on applying organic principles to home gardens were delivered to 236 Master Gardeners. How have the results been disseminated to communities of interest?Throughout the project, results were disseminated in face to face programs (field days and workshops) and farm visits, online educational materials (slide presentations and videos), peer-reviewed articles (research and extension), newspaper and radio interviews on recent research and extension projects, and in professional development workshops for Extension and other technical service providers. What do you plan to do during the next reporting period to accomplish the goals?This is the final year of this project.

Impacts
What was accomplished under these goals? For all objectives and years combined, this work was supported by state and federal competitive grants totaling $437,000 (for this faculty member only) and $28,000 of cash and in-kind support. Outputs include lead or co-author of 10 peer-reviewed journal articles and 9 proceedings papers, lead or co-author of 21 published abstracts at state and national professional conferences, Organized 15 professional development trainings and organized and/or led 46 sessions at state and county programs to an estimated 2,469 participants, led or co-authored 27 peer-reviewed Extension publications totaling 178,834 page views, led 27 video segments, and hosted 4 major statewide conferences. Objective 1. One MS student and one undergraduate honors student completed research projects on OA. Four competitive awards from USDA and SR-SARE provided funding. The rate of N transformation was studied in laboratory incubation studies and verified in the field. Ingredients in OA have unique rates of N transformations and are influenced negatively by soil pH extremes, and positively correlated with soil temperature (to 90°F) and soil moisture (to field capacity). This information improves our estimation of N release rates from organic fertilizers in Florida conditions. In field experiments performed on certified organic land, commercial OA granular fertilizer applied at IFAS recommendations resulted in competitive vegetable yields when applications were split over the season but not when 100% of OA was applied prior to planting. Because excess NO3-N can degrade groundwater quality but insufficient NO3-N will reduce yield, an on-farm experiment included N data collected from soil and leachate collected from buried lysimeters. Under ideal growing conditions, nitrogen from OA was not evident in leachate analysis. However, during leaching rains, OA were as likely as conventional fertilizers to leach NO3-N, thus all farmers must follow the same precautions to minimize risk to water quality. A PhD advisee is expanding this work to investigate the effects of OA plus biochar on soil nutrient and water retention. One refereed journal article, 2 proceedings papers, 2 Virtual Field Day video segments, and 4 extension publications were published. Objective 2. Management strategies to increase soil organic matter, cover crop nutrient uptake and suppress weeds were published in refereed journals (2 publications), 8 peer-reviewed fact sheets published on national and state extension web sites, 6 newsletter articles and 2 conference proceedings papers. One of the refereed journal publications was a report from a larger project involving pest suppression by cover crops. That publication was named as a top 10 downloaded article in HortTechnology in October 2009. Four competitive grants were awarded from USDA, SR-SARE, and CCAP. Three high school students completed research projects on cover crops. Data on plant tissue quality, above-ground biomass, N returns, and effects on pests now assist producers in selecting the best cover crop for their farming system. Studies on tropical legumes resulted in modification of previous recommendations for planting and termination strategies to obtain the most plant-available N. The same study provided strong support of combining species in a planting to obtain multiple benefits. Tropical legumes grown with cereal grains produced more biomass than monocultures alone, and produced similar N returns as legume monocultures. Objective 3. Although originally conceptualized to be conducted in the field, most of the field work was categorized under Objectives 1 and 2. Therefore, the work in this objective is geared to develop biologically-based greenhouse vegetable systems that rely on local and renewable organic amendments as nutrient sources, minimize water use, reduce risk to water quality, and are profitable. Organically-managed basil and spearmint produced greatest yields in a greenhouse trough system when granular poultry litter was a major ingredient in commercial OA. An invited presentation on organic herb production was given at the American Society for Horticultural Science (ASHS) Annual Meeting (2006). A review paper on nutrient management for organic greenhouse herbs was the 5th and 6th most downloaded manuscript from HortTechnology for October and November 2007; respectively. A second paper from this effort was recently accepted by HortTechnology for publication. Two Master's students are continuing the greenhouse work. One student is examining chlorine dioxide (ClO2) as a sanitizing agent for control of pythium in bell pepper production. A second student is developing an organic nutrient management program for colored bell pepper. Objective 4. Over the course of this project, a formal stakeholder advisory board was not formed for several reasons. First, the amount of input and the quality of input that I received was significant throughout the past five years. Second, the research and extension program was very diverse, and to develop one board with a reasonable number of people with expertise in the areas of programming I was responsible for would have been too great. Third, because I already had access to excellent community leaders in my committee work across the state, I would likely have been asking those very same people to serve on yet another committee. Out of respect for their time, and for the other reasons mentioned, I chose not to move forward with assembling a committee. When it was necessary to obtain an unbiased view of a complex issue, several different advisory boards were used to vet issues and get feedback including: The Small Farms Academy board, the UF-IFAS Extension leadership team, the Hort Department Chair Advisory Board, the Small Farms Conference Advisory Board, and the Florida SARE advisory board. Outcomes and Impacts Statewide educational programs with a sole focus on cover crops were delivered to nearly 700 participants since 2005. As a result of research and outreach efforts, the rye cultivar 'FLA 401'is now widely adopted by farmers. In addition, estimated nitrogen returns from leguminous cover crops over all experiments range from 34-101 kg ha-1 plant available nitrogen, and could offset synthetic fertilizer costs by $14.00 to $40.00 per hectare. The Organic Farming Field Day was the first UF-IFAS event of its kind dedicated to meet the unique educational needs of organic growers, and was featured on the front page of the Gainesville Sun (Sept 22, 2006). Evaluations were positive (90% satisfied or very satisfied). A major outcome of this effort is the professional relationships developed with our state's organic stakeholders, evidenced by 6 research and extension grants with a non-profit organization serving organic farmers, and 7 on-farm projects with organic farmers. Between 2006 and 2010, approximately 50% of producers attending UF/IFAS presentations on organic production indicated they were interested in transitioning to certified organic production. Producer and county faculty satisfaction with educational programs consistently rated >90% (satisfied, very satisfied) and knowledge gain based on pre-test/post-test paired comparisons (statistically, t-tests) was at least 60% for educational programs on sustainable and organic vegetable production. Since 2005, the number of organic farms has doubled to 280 in 2007. Part of that increase may be due to available educational resources and the knowledge gain of agents and growers. In a post-event evaluation of statewide Master Gardener training that included organic gardening, 91% of Master Gardeners and Extension agents believed the program provided the training and resources they could use to teach others vegetable gardening in the future, and that the overall quality of the program was excellent. 27% of agents believed the videoconference was an excellent medium for teaching vegetable gardening, the rest felt it was a good medium.

Publications

  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Treadwell, D.D., G.J. Hochmuth, R.C. Hochmuth, E.H. Simonne, S.A. Sargent, L.L. Davis, W.L. Laughlin, and A. Berry. 2011. Organically-Managed Greenhouse Basil and Spearmint Respond Differently to Fertilizer Source and Analysis In a Trough System. HortTechnology. 2011. 21(2):162-169
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Tyson, R.V., D.D. Treadwell, E.H. Simonne. 2011. Opportunities and Challenges to Sustainability in Aquaponic Systems. HortTechnology. 21 (1):6-13.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Stone, A., D. Treadwell and T. Coolong. 2011 What is eOrganic and how can it help foster a national organic agriculture research and outreach community? HortSci 46(9):86
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Beyer, A. D. Treadwell, D.J. Cantliffe. 2011 ASHS Hawaii Evaluating nutrient management systems for organically-produced greenhouse colored bell pepper (Capsicum annuum L.) HortSci 46(9):369
  • Type: Conference Papers and Presentations Status: Published Year Published: 2011 Citation: Rens, L.R. D. Treadwell, Harmon, C. J. Bartz and D. J. Cantliffe. 2011 ASHS Hawaii Chlorine dioxide as a disinfectant for Pythium aphanidermatum in a closed loop irrigation system for greenhouse bell pepper. HortSci 46(9):259


Progress 10/01/09 to 09/30/10

Outputs
Target Audience:The target audience included Florida, Southern Region and National producers, information providers included Extension faculty and staff, and other agriculture stakeholders such as certified crop advisors, Organic inspectors, industry and agency representatives, and community leaders. Changes/Problems:No changes to report. What opportunities for training and professional development has the project provided?Student mentoring and training was provided to 2 graduate students and 1 undergraduate student during this period. To serve the broader agricultural community, this faculty member provided statewide leadership among Florida small farm stakeholders (University faculty, regulatory personnel, buyers and distributors, producers, etc.) leading to community food systems that sustain the farm economy, preserve natural resources, and maintain consumer trust. My leadership has been recognized through invitations to serve as a Small Farms Focus Team Leader, as a Small Farms Academy Advisory Board member, and as a representative of the UF/FAMU Small Farms Team in various state and national meetings. Co-Chair, Executive Committee (with R. Hochmuth, N. Wilson, R. Kluson, and S. Kelly) and Chair, Educational Program for The Small Farms and Alternative Enterprises State Conferences Aug. 2010. (http://smallfarms.ifas.ufl.edu/floridasmallfarmsconference/2010/index.shtml) The 2010 Conference was approved as an in service-training. The first state-wide conference designed to meet the unique educational needs of small diversified farmers and those farmers engaged in alternative enterprises (bee-keeping, agri-tourism, etc.). Planning for the 2010 conference involved a 20 member stakeholder advisory group composed of growers, suppliers, food distributors, foundations, Extension educators, USDA agency representatives, Farm Credit, Farm Bureau and the Florida Department of Agriculture and Consumer Services. 2010 conference featured seven educational tracts delivered by 100+ faculty, industry experts and farmers, live animals, local food, a keynote address, farmer awards, and a large trade show (80 exhibitors). The event attracted 800 attendees. This event is a major commitment from IFAS both in time dedicated from state and county faculty as well as financial support, and was supported by FDACS Specialty Crop Block grants in 2009 and 2010. This has been an excellent opportunity to work collaboratively with UF and FAMU (1890's Land Grant) faculty to design and deliver effective and impactful programs. The 2010 Small Farm Conference evaluations were equally as supportive as the 2009 event. Respondents indicated that as a result of this event, they were confident they could develop better business skills (67%), would investigate alternative markets (44%) and improve the efficiency of their production systems (36%). Over 90% of respondents stated they would attend a 2011 conference. How have the results been disseminated to communities of interest?Florida Food Summit planning committee member, sponsored by the Office of Sustainability. Planned and executed the two-day event to facilitate networking and action among key stakeholders involved in farm to institution networks. April 12-13. Research results are regularly disseminated through in-service trainings, state small farms conference, county level trainings and meetings, and as a guest lecturer in undergraduate and graduate classes. Responded to state and county faculty's and agricultural stakeholders' needs via on-farm visits, office visits, phone and e-mail exchanges. Clientele contacts are 600-700 annually. Nationally, this faculty member is a leadership team member of an eXtension CoP, eOrganic. In addition to contributing to content, I also provide regular updates to Florida's farmers and extension on new content, services, etc. that eOrganic and eXtension can offer. Since eXtension's debut in February 2008, Florida consistently ranks 4th in number of visits by state (over 8,000 for June 2010 alone). 85% of these visitors are new, and 15% are returning. This high number of new visitors indicates that outreach efforts to direct people to eXtension are successful. Nearly 54% (8,100 of 15,000) of Cooperative Extension Professionals have eXtension IDs, and that number continues to increase. Cover Crops for Small Spaces. Program for members of the Simple Living Institute, a not-for-profit community organization promoting the home garden and local food movement. Sept. 2010 (Attendance: 35) Cover Crops for Improved Nutrition. Going Green to Save Green Program for central FL fruit producers. Lake County Extension, Sept. 2010 (Attendance: 30) Cover Crops 101. Crop Management School. Suwannee County Extension and NFREC, Live Oak, FL. Feb. 2010. (Attendance: 60) Successful Heirloom Vegetable Production. Co-presented with Dr. Aparna Gazula, Alachua County Extension. AgriTunity Conference. Bushnell, FL. Jan. 2010. (Attendance: 85) Healthy Foods, Healthy Cities. Strategies to Integrate Agriculture into Urban Centers. Organizer, presenter. Training to Extension faculty, Kissimmee, FL (Attendance 65) What do you plan to do during the next reporting period to accomplish the goals?THe next reporting period will be the final year of this CRIS project. Activities presented here will continue or be finalized, and the current program will continue to evolve with no significant changes in focus.

Impacts
What was accomplished under these goals? Objective 1 - Two Master's students are continuing the greenhouse work. Libby Rens is examining chlorine dioxide (ClO2) as a sanitizing agent for control of pythium in bell pepper production. Allison Beyer is developing an organic nutrient management program for colored bell pepper. These students were supported by competitive scholarships and Departmental stipends. Objective 2 - Data on plant tissue quality, above-ground biomass, N returns, and effects on pests now assist producers in selecting the best cover crop for their farming system. Our studies on tropical legumes resulted in modification of previous recommendations for planting and termination strategies to obtain the most plant-available N. The same study provided strong support of combining species in a planting to obtain multiple benefits. Tropical legumes grown with cereal grains produced more biomass than monocultures alone, and produced similar N returns as legume monocultures. This work was supported by USDA CSREES-Organic Research and Education Initiative, and will be continued with a recently awarded SARE on Farm grant. Objective 3 - In field experiments performed on certified organic land, commercial OA granular fertilizer applied at IFAS recommendations resulted in competitive vegetable yields when applications were split over the season but not when 100% of OA was applied prior to planting. Because excess NO3-N can degrade groundwater quality but insufficient NO3-N will reduce yield, an on-farm experiment included N data collected from soil and leachate collected from buried lysimeters. Under ideal growing conditions, nitrogen from OA was not evident in leachate analysis. However, during leaching rains, OA were as likely as conventional fertilizers to leach NO3-N, thus all farmers must follow the same precautions to minimize risk to water quality. PhD advisee Seth Friedman is expanding this work to investigate the effects of OA plus biochar on soil nutrient and water retention. This work is supported by a SARE Graduate student grant ($14,999). Objective 4 - This faculty member continues to rely upon a diverse group of stakeholders for input. No formal advisory board will be assembled for the CRIS project, but we do have formal advisory boards for the Small Farms and Alternative Enterprises Extension team, as well as the state SARE advisory board. We have meetings twice a year with these boards, and their advice and input is much appreciated. Treadwell, D., C. Chase, A. Cho, and M. Alligood. Decomposition of Sunn Hemp (Crotalaria juncea L.) Residue Grown for Seed Production in Florida. American Society for Horticultural Science Annual Meeting. Palm Desert, CA. Aug. 2010. Treadwell, D.D., R. Hochmuth, N. Wilson, R. Kluson, and S.A. Kelly. Building Capacity for Florida's Small Farm Specialty Crop Industry with a Statewide Conference. American Society for Horticultural Sciences Annual Meeting, Palm Desert, CA July 2-5 2010. Treadwell, D. Moderator for Florida Food Summit keynote speaker, Michael Dimock, President, Roots of Change, a Nonprofit Organization Dedicated to Developing a State-Based Food System in California. Apr. 2010. Gainesville, FL. Treadwell, D. Reintegrating Agriculture into The Urban Environment: Regulatory and Planning Hurdles for the Local Food Movement. Panel Organizer and Moderator. 2010 Public Interest Environmental Conference, Levin College of Law. Gainesville, FL.

Publications

  • Type: Journal Articles Status: Published Year Published: 2010 Citation: Simonne, E., C. Hutchinson, J. DeValerio, B. Hochmuth, D. Treadwell, A. Wright, B. Santos, A. Whidden, G. McAvoy, X. Zhao, and T. Olczyk. 2010. Keeping Water and Nutrients in the Root Zone of Vegetables. HortTechnology. 20 (1):143-152
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2011 Citation: Treadwell, D.D., G.J. Hochmuth, R.C. Hochmuth, E.H. Simonne, S.A. Sargent, L.L. Davis, W.L. Laughlin, and A. Berry. 2010. Organically-Managed Greenhouse Basil and Spearmint Respond Differently to Fertilizer Source and Analysis In a Trough System. HortTechnology. Accepted 4/5/2010MS #01688
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Cho, A.*, C.A. Chase, R. Koenig and D. Treadwell. 2010. Evaluation of Sixteen Accessions of Sunn Hemp (Crotalaria juncea) for Seed Production Potential in Florida. HortScience. 45(8):S240
  • Type: Other Status: Published Year Published: 2010 Citation: Taber, S.*, D. Treadwell, R. Tyson and E. Simonne. 2010. Foliar micronutrients in closed aquaponics systems: Maintaining healthy levels and sourcing appropriate supplements. EDIS, HS408. http://edis.ifas.ufl.edu/hs408
  • Type: Other Status: Published Year Published: 2010 Citation: Treadwell, D. R. Hochmuth, L. Landrum and W. Laughlin. 2010. Microgreens  A New Specialty Crop. EDIS, HS1164. http://edis.ifas.ufl.edu/hs1164
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Treadwell, D.D., C.A. Chase, A.H. Cho and M. Alligood. 2010. Residue Quality and Decomposition Rate of Terminated Sunn Hemp Grown for Seed. HortScience. 45(8):138
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: A. H. Cho*, C. A. Chase, D. D. Treadwell and R. L. Koenig. 2010. Evaluation of Phenotypic Characteristics of Sixteen Accessions of Sunn Hemp in Florida. Amer. Soc. Hort. Sci. Annual Meeting. Electronic Abstract: http://ashs.confex.com/ashs/2010/webprogram/Paper3686.html
  • Type: Conference Papers and Presentations Status: Published Year Published: 2010 Citation: Davies, L.R.R.*, D. D. Treadwell, D. J. Cantliffe, J. A. Bartz and M. R. Alligood. 2010. Vigor Response of Greenhouse Bell Pepper Due to Chlorine Dioxide Sanitized Irrigation Water. HortScience. 45(8):S97
  • Type: Other Status: Published Year Published: 2010 Citation: Treadwell, D.D. 2010. Introduction to Organic Vegetable Production. EDIS, CV118/ HS720, http://edis.ifas.ufl.edu/CV118. (Minor revision of original 2006 version, and subsequent revisions in 2007)


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: Research A SARE research and education project "Selecting a sunn hemp cover crop genotype for weed suppression and seed production" was initiated in spring 2008. The objective for this research is to evaluate rate of disappearance of sunn hemp tissue carbon and nitrogen following seed harvest. To date, season two is still in progress. Buried litter bags filled with sunn hemp residue will be removed from the field weekly from January through March 2010. A complimentary randomized, replicated 2 year study that investigated the capacity for sunn hemp to utilize soil potassium was completed in summer of 2009. Year one findings were reported to an audience of growers, technical service providers and researchers at the Florida State Horticultural Society's annual meeting. A paper summarizing results from year one was published in the proceedings (below). Manuscripts for both experiments are in preparation. In addition, a full proposal was submitted to SARE in fall of 2009 to continue this research. A second SARE-funded grant is an on-farm grant in participation with a local organic farmer to improve the efficiency of the nutrient management program via monitoring soil solution nitrate. This is accomplished by collecting soil water from two submerged lysimeters (buried to 5 feet) in a deep sandy soil. Soil water was extracted from the holding basin every other week for the course of the spring and fall vegetable season. This project is ongoing until summer 2010. Dissemination Field research on the USDA Integrated Organic Program-funded project "Crop Diversification Complexity and Pest and Beneficial Organism Communities in Humid Tropical and Subtropical Climatic Regimes" was completed in summer 2008. In fall 2009, a two-day extension workshop was designed and delivered to 30 organic farmers and extension professionals in the US Virgin islands in St. Croix in collaboration with the University of the Virgin Islands collaborators. The workshop was focused on research results from the project and included farm tours and round table discussions of relevant topics. Results from this CRIS research project and relevant work from academic colleagues was disseminated through a total of 33 publications this year (selected publications are summarized below). A major effort has included using the internet for information dissemination. In 2009, the UF Small Farms and Alternative Enterprises website received 1.8 million hits. This is due in part to the popular Small Farms Conference held in August 2009 in Kissimmee, FL. This two day event was the result of 2 years of grass-roots planning and attracted over 800 farmers and technical service providers. Other outputs for web readership include articles in the Organic Agriculture resource area of eXtension, UF's Virtual Field Day, and the Organic Farming area on the small farms website. Total number of web visits as a result of this program was 96,873. In addition, numerous extension publications were published through eXtension and the University of Florida's electronic fact sheet library. Both require peer review and editorial review prior to acceptance. PARTICIPANTS: Individuals who contributed to the project: Two high school students completed independent study over the summer as part of a university program to mentor high school students interested in careers in science. During their 6 week stay, they developed a hypothesis, performed an experiment, collected and analyzed data. One project focused on the rate of nodulation on tropical summer legume cover crops in various planting arrangements, and the other focused on potassium uptake by summer legumes. One student received an award for Best Poster. One MS student and one PhD student began their programs in fall 2009. Partner organizations include: Florida Organic Growers and Consumers, Inc. (Gainesville, FL), Farm Bureau, Farm Credit, Florida Department of Agriculture, Florida Agricultural and Mechanical University, University of the Virgin Islands and the eOrganic Community of Practice in eXention. TARGET AUDIENCES: State/Regional Clientele for extension programming includes conventional and organic specialty crop producers. In addition, a number of row crop prudcers using cover crops are included. Technical service providers including extension professionals, crop advisors, industry reps, and faculty from related disciplines also benefit from the outputs of this program. National Content development and administrative duties were completed for eOrganic. Content launched in early 2009. As stated in the eOrganic Extension Community fact sheet: The current content is focused on general organic agriculture, dairy production and vegetable production. The content published on this site is collaboratively authored and reviewed by a community of university research and extension personnel, agricultural professionals, farmers and certifiers with experience and expertise in organic agriculture. The target audience is the same as the community described above. PROJECT MODIFICATIONS: No major modifications to the project were made in 2009.

Impacts
Knowledge change was measured at several extension programs during the year. A Master Gardener's webinar was delivered to nearly 400 volunteer master gardeners across the state. Topics included organic farming practices and IPM. Of those attendees who submitted an evaluation (n=121) 94% reported an increase in knowledge. 90% of those same respondents indicated they would change their current gardening practices based on their new knowledge. Florida Small Farm and Alternative Enterprises Conference" was held at the Osceola Heritage Park, Kissimmee, Florida on August 1-2, 2009. In attendance were farmers, allied industry representatives, researchers, educators, institutional members, policy-makers, small farm commodity associations, foundations, and others interested in strengthening the small farm community in Florida. The conference included many activities that benefitted the small farms industry: Opening session featuring Innovative Farmer Spotlights, A general session featuring keynote speaker knowledgeable on sustainable agriculture, Dr. John Ikerd, Concurrent educational sessions and workshops to share results of groundbreaking research and provide educational support for producers to operate sustainable and profitable enterprises, An exhibition area to introduce new products and technologies to small producers, and the facilitation of farmer networking during sessions, and refreshment breaks and lunches featuring local products from Florida small farms. The Small Farms Conference evaluation (n=212) indicated an 89% increase in knowledge gain and the same percentage indicated the intent to change practices based on their new knowledge. The attendees noted that the networking opportunities were very valuable as well.

Publications

  • Treadwell, D.D., G.J. Hochmuth, R.C. Hochmuth, E.H. Simonne, S.A. Sargent, L.L. Davis, W.L. Laughlin, and A. Berry. 2010. Organically-Managed Greenhouse Basil and Spearmint Respond Differently to Fertilizer Source and Analysis In a Trough System. Submission to HortScience. In review.
  • Gill, H., R. McSorley, and D. Treadwell. 2009. Comparative performance of different polyethylene films for soil solarization. HortTechnology. 19 (4):769-774
  • Treadwell, D.D., C.A. Chase, A.Cho, M. Alligood and J. Elsakr. 2009. Potential for sunn hemp (Crotalaria juncea L.) to utilize soil potassium. Proc. Fla. State Hort. Soc. Vol. 122. In Press.
  • Treadwell, D., J. Riddle, M. Barbercheck, D. Cavanaugh-Grant, and E. Zaborski. 2009. What is organic farming. Organic Agriculture Resource Area. http://www.extension.org/article/18655
  • Treadwell, D., N. Creamer and K. Baldwin. 2009. An introduction to cover crops for organic farming systems. Organic Agriculture Resource Area. http://www.extension.org/article/18542
  • Treadwell, D., W. Klassen, S. Shewey, M. Alligood. 2009. Buying and sourcing cover crop seed for organic farming systems. Organic Agriculture Resource Area. http://www.extension.org/article/18654
  • Treadwell, D. 2009. Introduction to cover cropping in organic farming systems. Organic Agriculture Resource Area. http://www.extension.org/article/18637
  • Treadwell, D.D. 2009. Introduction to Organic Vegetable Production. EDIS, CV118/ HS720, http://edis.ifas.ufl.edu/CV118. (Minor revision of original 2006 version, and subsequent revision in 2007.)
  • Gaul, S.A., R.C. Hochmuth, G.D. Israel, and D. Treadwell. 2009. Characteristics of Small farm Operators in Florida: Economics, Demographics, and Preferred Information Channels and Sources. http://edis.ifas.ufl.edu/WC088
  • Palenchar, J., D.D. Treadwell, L. Datnoff and A. Gevens. 2009. Cucumber Anthracnose in Florida. http://edis.ifas.ufl.edu/PP266
  • Stephens, J., S. Park-Brown, D. Treadwell, S. Webb and A. Gevens. 2009. Florida Vegetable Gardening Guide. http://edis.ifas.ufl.edu/VH021


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Research was performed in two separate projects during the past year. Field research on the USDA Integrated Organic Program-funded project "Crop Diversification Complexity and Pest and Beneficial Organism Communities in Humid Tropical and Subtropical Climatic Regimes" was completed in summer 2008. An oral presentation was given at the American Society for Horticultural Sciences National Meeting on this work and was titled "Soil nitrogen responses to increasing crop diversity and rotation in organic vegetable production systems". We observed a rapid decline in soil nitrogen following cover crop termination and soil incorporation as well as vegetable crop harvest. Soil organic matter increased slightly following initial contributions of compost and cover crops, but declined over the course of the trial. Preliminary analysis of treatment differences were highly variable, but additional statistical measures could identify differences. The manuscript for this work is in preparation. Two new projects were initiated. Both are funded by Southern Region SARE. A research and education project "Selecting a sunn hemp cover crop genotype for weed suppression and seed production" was initiated in spring 2008. My objective for this research is to evaluate rate of disapearance of sunn hemp tissue carbon and nitrogen folowing seed harvest. Because sunn hemp is a fibrous crop that becomes increasingly woody with age, management of plant material following seed harvest (which can take over 150 days after seeding) will be an important consideration for farmers wishing to produce seed as a value-added cover crop. To date, season one is still in progress. We are monitoring soil nitrate and ammonium. In addition, we are removing litter bags filled with sunn hemp residue (buried to less than 5 cm) and analyzing for weight loss (dry weight basis) and carbon and nitrogen content. The second SARE funded grant is an on-farm grant in participation with a local organic farmer. Our goal here is to improve the efficiency of the nutrient management program via monitoring soil solution nitrate. This is accomplished by collecting soil water from two submerged lysimeters (buried to 5 feet) in a deep sandy soil. Soil water will be extracted from the holding basin every other week for the course of the spring vegetable season. The lysimeters were buried in the fall, and we are anticipating the spring vegetable crop planting. PARTICIPANTS: Individuals who contributed to the project: One high school student interned in my lab over the summer as part of a university program to mentor high school students interested in careers in science. During his 6 week stay, he developed a hypothesis, performed an experiment, collected and analyzed data. His project was nested in the SARE sunn hemp project. He received a 99/100 for his oral presentation and won a Best Paper award for his efforts. The work will be repeated next summer, and results published in a scientific journal. Partner organizations include: Florida Organic Growers and Consumers, Inc. (Gainesville, FL), Farm Bureau, Farm Credit, Florida Department of Agriculture, and the eOrganic Community of Practice. Training and professional development: In 2008, one day-long workshop was conducted for extension county faculty to explore the data results and their potential significance to Florida sustainable vegetable systems. My role was to present the nutrient management aspect. We toured the field and observed 8 week old summer cover crops (a replicate of our field trial), and proceed to the classroom for round-table discussions on cover crop management, soil nitrogen and soil organic matter. The workshop was successful. 32 attended. TARGET AUDIENCES: In addition to the existing target audience of Florida producers, information providers and other agriculture stakeholders, development of materials for a new, national audience is underway. Content development and administrative duties were completed for eOrganic. Content is scheduled for a soft launch in winter 2009. As stated in the eOrganic Extension Community fact sheet: The current content is focused on general organic agriculture, dairy production and vegetable production. The content published on this site is collaboratively authored and reviewed by a community of university research and extension personnel, agricultural professionals, farmers and certifiers with experience and expertise in organic agriculture. The target audience is the same as the community described above. eOrganic is planning on an initial release of over 200 articles and video segments. The impact of this work will be determined following the full launch in fall 2009. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
I planned, organized and implemented several in-service trainings for extension faculty during the past year. These sessions attracted over 100 attendees, and a knowledge gain of at least 60% was reported in each session. Most of these sessions were interactive, with attendees participating in in-field activities, round-table discussions, and small group work. I was the lead author on 5, and co-author on 4 new extension fact sheets that are located on UF's electronic library of extension fact sheets EDIS: http://edis.ifas.ufl.edu. These publications were visited by over 9,500 people last year. All of these publications are on cover crops, sustainable agriculture, and nutrient and water management. To assess the extent of current adoption of technology and extent to which small farmers are implementing sustainable agriculture methods, we authored a survey instrument that was mailed to 850 small farmers that attended UF or FAMU educational programs in the past 24 months. The response rate was 38%, and these results are just now being analyzed. We anticipate the results from this survey will help us to identify areas where information is needed, how farmers prefer to be education (method and approach), and gain general knowledge about their production systems as a group.

Publications

  • Treadwell, D., W. Klassen, M. Alligood and S. Shewey. 2008. Annual cover crops in Florida vegetable systems. Part III. Buying and Sourcing. http://edis.ifas.ufl.edu/HS390.
  • Simonne, E., R. Hochmuth, J. Bremen, W. Lamont, D. Treadwell and A. Gazula. 2008. Drip irrigation systems for small conventional vegetable farms and organic vegetable farms. http://edis.ifas.ufl.edu/HS388
  • Treadwell, D. and P. Huang. 2008. Buckwheat: A cool season cover crop for Florida producers. http://edis.ifas.ufl.edu/HS386.
  • Refereed Publications Treadwell, D., N. Creamer, G. Hoyt, and J. Schultheis. 2008. Nutrient management with cover crops affects development and yield in organically-managed sweetpotato systems. HortScience. 43(5):1423-1433.
  • Tyson, R., E. Simonne, D. Treadwell, M. Davis, and J. White. 2008. Effect of water pH on yield and nutritional status of greenhouse cucumber grown in recirculating hydroponics. J. Plant Nutrition. 31:2018-2030.
  • Tyson, R., E. Simonne, D. Treadwell, J. White, and A. Simonne. 2008. Reconciling pH for ammonia biofiltration and cucumber yield in a recirculating aquaponic system with perlite biofilters. HortScience. 43:719-724.
  • Simonne, E., C. Hutchinson, J. DeValerio, B.Hochmuth, D. Treadwell, A. Wright, B. Santos, A. Whidden, G. McAvoy, X. Zhao, and T. Olcyzk. 2008. Keeping water and nutrients in the root zone of vegetables. HortTechnology. In press.
  • Non-refereed Publications Treadwell,D., A. Simonne, T. Nkambule, R. Hochmuth, W. Laughlin, T. Olczyk, C. Peavy and C. Rogers. 2008. Yield, chemical composition and eating quality of heirloom tomatoes grown in the subtropical climate of Florida. Proc. Fla. State Hort. Soc. In press.
  • Electronic Publications Thralls, E. and D. Treadwell. 2008. Home vegetable garden techniques: Hand pollination of squash and corn in small gardens. http://edis.ifas.ufl.edu/HS3098.
  • Simonne, A. and D. Treadwell. 2008. Minimizing food safety hazards for organic growers. http://edis.ifas.ufl.edu/FY1062.
  • Nguyen, T. A. Wysocki and D. Treadwell. 2008. Economics of the organic industry in Florida. http://edis.ifas.ufl.edu/FE732.
  • Treadwell, D. and M. Swisher. 2008. Understanding the USDA Organic label. http://edis.ifas.ufl.edu/HS397.
  • Treadwell, D., W. Klassen, and M. Alligood. 2008. Annual cover crops in Florida vegetable systems. Part I. Objectives: Why grow cover crops. http://edis.ifas.ufl.edu/HS387.
  • Treadwell, D., W. Klassen, and M. Alligood. 2008. Annual cover crops in Florida vegetable systems. Part II. Production. http://edis.ifas.ufl.edu/HS389.


Progress 10/01/06 to 09/30/07

Outputs
OUTPUTS: Research was initiated on the project in May 2006, prior to the final approval of the CRIS project proposal. Collaboration on a USDA Integrated Organic Program (C.Chase, PI) to study nutrient management in organic vegetable systems is underway. a 2.5 field trial on certified organic land at Plant Science Research and Education Unit (PSREU) in Citra, FL is in its second year, and will be completed in Summer 2008. Specifically, my program is investigating the impact of green manure cover crops and commercially formulated fertilizer blends on the nutrient use efficiency, crop yield and quality of organic broccoli, squash, sweet corn and beans. One Master of Science student graduated in August 2007 thesis title "Nutrient release from organic amendments approved for use in organic production." and her manuscripts are in preparation for publication. One PhD student began in August 2007 and will pursue research on the impacts of cover crop and vegetable polycultures (several species grown at the same time and space) on phosphorus nutrient use efficiency. One SARE proposal has been submitted to examine the cover crop sunn hemp (Crotalaria juncea) as a value added cover crop for seed production for small to medium sized farmers in the subtropics. Work was completed on organic greenhouse herb production from a CSREES TStar grant (G.Hochmuth, PI). A manuscript is in preparation for publication to ASHS HortScience. Several extension fact sheets have been submitted, and several field days were conducted. PARTICIPANTS: There is no new participant information to report. Participants are as noted in CRIS proposal. TARGET AUDIENCES: The target audience remains small to medium sized vegetable producers, organic producers of all sizes, and county extension faculty. A new effort to satisfy the national organic audience was initated this year. Founding member of eOrganic, a new Community of Practice in eXtension. Invited and sponsored attendance at the eOrganic Visioning Meeting in Portland, Oregon February 26-March 1, 2007 with 40 other extension professional from US land grant universities, certified organic producers (Jim Price, Horizon dairy), non-governmental non-profits (Farm Aid, OMRI), government-supported agencies (ATTRA), and other industry leaders (NewFarm) to identify educational needs and research opportunities in organic and sustainable agriculture. I am the content leader for cover crops. PROJECT MODIFICATIONS: There are no major changes to report.

Impacts
Since research is still ongoing, so conclusions and impacts from the field work are not yet available. Preliminary reports have been prepared for county faculty via workshops, field days, and a newsletter article. An extension and outreach program was funded through University of Florida to support the development of educational materials for FL organic producers (Treadwell, PI). Eleven faculty have developed extension fact sheets respective to their expertise on organic farming, and these are currently in review. Short films have been recorded that will be added to UF's extension program "Solutions for Your Life Virtual Field Days". These films include nutrient and pest management in organic farming systems, as well as cover crop management.

Publications

  • Journal Articles Treadwell, D. D., Hochmuth,G. J., Hochmuth, R. C., Simonne,E. H., Davis,L. L., Laughlin,W., Sargent,S. A., Li, Y., Olczyk,T., Sprenkel,R. K., and Osborne, L. S. 2007. Nutrient Management for Organic Greenhouse Culinary Herbs: Where Are We Now HortTechnology. 17(4):461-466.
  • Book chapter Treadwell, D.D. 2006. Introduction to Organic Vegetable Production. Chapter 24, pp.127-140. In: S.M. Olson and E. Simonne (Eds.) 2006-2007 Vegetable Production Handbook for Florida, Vance Pub., Lenexa, KS.
  • Extension articles Hochmuth,R.C., Treadwell,D.D., Hochmuth,G.J., Simonne, E.H., Olczyk, T., Migliaccio, K.W., Li,Y.C.,Sprenkel, R.K., Osborne L.S. 2007. Organic greenhouse fresh cut herb production: soilless container systems. EDIS, AE408, http://edis.ifas.ufl.edu/AE408
  • Sierra, A., Simonne, E. y Treadwell, D. 2007. Principios y practicas para el manejo de nutrientes en la produccion de Hortalizas. EDIS, HS356, http://edis.ifas.ufl.edu/HS356
  • Abstracts Treadwell, D. D., Hochmuth,G. J., Hochmuth,R. C., Sargent,S. A., Simonne,E. H., Davis,L. L., Laughlin,W. L., Berry,A., Li,Y., Olczyk, T. , Sprenkel R. K., and Osborne,L. S. 2007. Organic Greenhouse Production of Basil and Spearmint: Nutrient Uptake and Postharvest Quality. ASHS, Scottsdale, AZ. 07/15/07.
  • Sierra, Alejandra , Treadwell,Danielle, Simonne, Eric and Graetz, Donald. 2007. Using Degree Days to Predict Nitrogen Mineralization from Organic Amendments. SR-ASHS, Mobile, AL. HortScience 42(3):438
  • Ben-Avraham, R., Treadwell,D. D., and Alligood, M.A. 2007. Nitrogen mineralization in greenhouse turnips (Brassica campestris L.) amended with compost and organic fertilizer. SR-ASHS, Mobile, AL. HortScience 42(3):435.