Progress 09/01/06 to 08/31/10

Outputs
OUTPUTS: 1) Samples and data from the 2009 field station experiment and the two on-farm trials were analyzed for total biomass production, weeds, total N content and % N fixed. The second experiment at the Freeville Ag. Experiment Station tested the five best-performing warm season legume species identified in the first screening experiment conducted in 2008. These cover crops were planted in early July and remained in the field for 2-4 months. The experimental design was a split-plot design, with four replicate blocks per field. The main treatment was legume species and the sub-treatments were monocultures of the legumes and non-legumes, and a replacement series of legume-non legume mixtures at different seeding ratios. In 2009 the viny legumes included: Forage Soybean (Glycine max, var. Tyrone), Cowpea (Vigna unguiculata), and Chickling vetch (Lathyrus sativus). The non-viny legume species were Berseem clover (Trifolium alexandrinum) and Crimson clover (Trifolium incarnatum). Buckwheat (Fagopyrum esculentum) and Japanese Millet (Echinochloa frumentacea) were grown in mixtures with both the viny and the non-viny legumes. The viny species were also grown in mixtures with Sorghum-Sudan (Sorghum bicolor), it was expected that the high biomass production and tall stature of Sorghum Sudan (Sorghum bicolor) could provide structure for the viny species to grow up against. The non-viny legumes were also grown with Flax (Linum usitatissimum). Two additional experiments were established with a smaller number of treatments in fields of two collaborating farmers who selected the cover crops they were interested in testing. The results were analyzed and summarized in a master's thesis by van Zyl. 2) We examined the significance of free-living diazotrophs in experimental plots that spanned a gradient of agricultural intensification across a matrix of tillage and crop management practices. PARTICIPANTS: Laurie Drinkwater: Laurie is the PD and in addition to her role in helping with the planning and implementation of the overall project, she is analyzing the N fixation results from the first cover crop experiment. Dan Buckley: Co-PI, with expertise in microbial ecology. Dan assisted with the supervision of Dr. Julie Grossman who was a post-doc on the project. She conducted research to characterize the bacterial communities in soybean nodules from organic and conventionally managed fields. Meagan Schipanski conducted the on farm experiments and completed her PhD in 2009. Ann Piombino: Ann is a Research Technician in the Drinkwater lab. She helped to collect biomass samples from the cover crop experiment, process and analyze the samples. Burtie van Zyl is a graduate student in the Drinkwater lab who conducted research on warm season nitrogen fixing cover crops for use in organic rotations. He completed his Master's degree in Spring 2010. Partner organizations: Northeast Organic Farming Association, New York, PO Box 880 Cobleskill, NY 12043-0880; Farmscape Ecology Program, Hawthorne Valley Farm, Ghent, NY 12075, many collaborating farmers. TARGET AUDIENCES: The primary target audience for our project is organic farmers in the northeast, however some of the information we have generated is broadly applicable to all organic farmers who rely on nitrogen-fixing green manures to manage soil nitrogen fertility. Our secondary audience includes extension educators, farmer organizations and other researchers who are studying legume cover crops. We have undertaken a number of efforts to reach these audiences. Throughout the project we reached regional organic farmers through the workshop we presented at organic farmer meetings, including NOFA New York and NOFA Vermont as well as numerous field days and workshops sponsored by various Cornell University affiliated extensionists and researchers. In January 2010, we sponsored a half-day workshop at the NOFA New York meeting where we reported many of our findings to growers and extension educators. The information resulting from this research has also been included in a series of columns we produced for publication in various newsletters targeting farmers and extension educators (Northeast Organic Farming Association, New York, Cornell Small Farm Center, other NY extension newsletters). These newsletters target farmers in the northeast, particularly New York, including organic as well as conventional family farms. We continued to publish newsletter columns during this past year. In June 2011, the findings of this project will be included in a feature article to be published in The Natural Farmers, the flagship publication of Northeast Organic Farming Association that reaches thousands of organic farmers in the northeast region. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Several key findings resulted from our experiment with legumes growing in monocultures and mixtures. As expected, there were significant differences in the performance of the five legume species in terms of both N fixation and weed suppression. In monoculture, Crimson Clover fixed the most N and it was also the most weed suppressive legume while cowpea fixed the lowest amount of N in both years. Interestingly, cowpea still produced significant biomass by accessing more soil N than any of the other legumes. The legumes in all the mixtures, except in the Buckwheat mixture, showed increased rates of N fixation compared to monocultures. Mixtures were not consistently more effective in suppressing weeds compared to monocultures. Instead, the weed suppressive capacity of the mixtures depended on the species involved. Buckwheat mixtures were the most weed suppressive. Because of the replacement series design used in our experiment, we were able to rank the competitive ability of the non-legumes. The competitive ability of the non-legumes can be ranked as follows: Buckwheat > Sorghum Sudan > Japanese Millet > Flax. In general there was a functional trade-off between N fixation and weed suppression: mixtures that are effective at suppressing weeds (Buckwheat mixtures) also suppress legumes and legumes that are competitive (Cowpea) in mixture do not fix a lot of N. In mixtures containing species with complementary growth times (Clovers and Sorghum Sudan / Buckwheat), mowing the competitive non-legumes after they reached maximum growth increased legume biomass five-fold in Buckwheat mixtures and two-fold in Sorghum Sudan mixtures. Nitrogen fixation increased eight- to ten-fold in clovers following Buckwheat mowing. Overall, our study showed that there is great potential to optimize N fixation while maintaining effective weed suppression through careful pairing of legume and non-legume species with complimentary functional traits. Our work on free-living N-fixation rates and diazotroph community composition showed that both were impacted by crop biomass management practices and by interactions between tillage and biomass management while soil characteristics were mainly driven by tillage. Total N-fixation attributed to free-living diazotrophs was highly dynamic both spatially and temporarily and ranged from approximately 0-20 kg N ha-1yr-1. The main cause of temporal variation in N-fixation rates could not be determined in the present study. However, when averaged across time, the data suggest that variation in diazotroph community composition has a greater impact on N-fixation rate than soil variables at the site. N-fixation rates displayed a saturating response to increases in diazotroph community richness and evenness and were lowest in soils with the highest levels of organic matter inputs and in which potential N-mineralization rates were greatest. These results show that changes in the community structure of free-living diazotrophs in soils can impact N-fixation rates.

Publications

• Buckley, D. H. (2010) Stable Isotope Probing Techniques Using 15N. In J. C. Murrell and A. S. Whiteley (eds.). Stable Isotope Probing and Related Technologies. ASM Press, Washington, D.C.
• Buckley, D. H. (2010) Assessing the Diversity of the Unseen Majority. In Sigurdur Greipsson (ed.). Restoration Ecology. Jones and Bartlett Publishers, Inc., Boston.
• Hsu, S., M. M. Stone, D. H. Buckley (2009) "Evidence for the Functional Significance of Microbial Diversity among Free-living Diazotrophs in Soils of a Long Term Agricultural Site" Published in the Proceedings of the Soil Science Society of America Annual Meeting.
• Noar, J. and D. H. Buckley (2009) Ideonella azotifigens sp. nov., an aerobic diazotroph of the Betaproteobacteria isolated from grass rhizosphere soil, and emended description of the genus Ideonella. International Journal of Systematic and Evolutionary Microbiology 59:1941-1946.
• Schipanski M.E., L. E. Drinkwater. (2010) Nitrogen fixation of red clover interseeded with winter cereals across a management-induced fertility gradient. Nutrient Cycling in Agroecosystems. In press.
• Hsu, S. and D. H. Buckley (2009) Correspondence between diazotroph diversity and rates of nitrogen fixation in soil. International Society for Microbial Ecology Journal 3:124-136.

Progress 09/01/08 to 08/31/09

Outputs
OUTPUTS: 1. The second experiment was established at the Freeville Ag. Experiment Station to test the five best-performing warm season legume species. These cover crops were planted in early July and remained in the field for 2-4 months. The experimental design in both years was a split-plot design, with four replicate blocks per field. The main treatment was legume species and the sub-treatments were monocultures of the legumes and non-legumes, and a replacement series of legume-non legume mixtures at different seeding ratios. In 2009 the viny legumes included: Forage Soybean (Glycine max, var. Tyrone), Cowpea (Vigna unguiculata), and Chickling vetch (Lathyrus sativus). The non-viny legume species were Berseem clover (Trifolium alexandrinum) and Crimson clover (Trifolium incarnatum). Buckwheat (Fagopyrum esculentum) and Japanese Millet (Echinochloa frumentacea) were grown in mixtures with both the viny and the non-viny legumes. Because these species have moderate growth, stature and biomass production it was expected that these two species would not out-compete the non-viny legumes, while providing sufficient structure for the viny legumes to grow up against. The viny species were also grown in mixtures with Sorghum-Sudan (Sorghum bicolor), it was expected that the high biomass production and tall stature of Sorghum Sudan (Sorghum bicolor) could provide structure for the viny species to grow up against. The non-viny legumes were also grown with Flax (Linum usitatissimum). Two additional experiments were established with a smaller number of treatments in fields of two collaborating farmers. 2. Samples and data from the 2008 experiment were analyzed and the results were summarized and used to design the second experiment. These data were added into our data base for cover crop assessment tool development. 3. We participated in several field days and presented findings from the first year of cover crop experiments. In August 2009, we tested a multi-dimensional cover crop evaluation tool with about 20 growers at the annual Cornell Organic Cropping Systems Field Day. PARTICIPANTS: Laurie Drinkwater: Laurie is the PD and in addition to her role in helping with the planning and implementation of the overall project, she is analyzing the N fixation results from the first cover crop experiment. Meagan Schipanski conducted the on farm experiments and completed her PhD in 2009. Ann Piombino: Ann is a Research Technician in the Drinkwater lab. She helped to collect biomass samples from the cover crop experiment, process and analyze the samples. Burtie van Zyl is a graduate student in the Drinkwater lab who is conducting research to develop additional nitrogen fixing cover crops for use in organic rotations. Partner organizations: Northeast Organic Farming Association, New York, PO Box 880 Cobleskill, NY 12043-0880; Farmscape Ecology Program, Hawthorne Valley Farm, Ghent, NY 12075, many collaborating farmers. TARGET AUDIENCES: In addition to the undergraduates who participated in the Sustainable Ag. Scholars Program, the farmers who serve on the advisory committee and the farmer research collaborators we reached additional organic farmers through the workshop we presented at the NOFA meeting and a presentation on nitrogen fixing cover crops to growers in the Hudson Valley. The information resulting from this research has been included in a series of columns we produced for publication in various newsletters targeting farmers and extension educators (Northeast Organic Farming Association, New York, Cornell Small Farm Center, other NY extension newsletters). These newsletters target farmers in the northeast, particularly New York, including organic as well as conventional family farms. Workshops: Conducting your own on-farm experiments and trials. Organized by B. van Zyl and L.E. Drinkwater. Empire State Fruit and Vegetable Expo & Farmers' Direct Marketing Conference. Rochester, NY. Jan. 2009. (Attendance: 25) What can legumes do for you Understanding biological nitrogen fixation from the ground up! Empire State Fruit and Vegetable Expo & Farmers' Direct Marketing Conference. Rochester, NY. Jan. 2009. (Attendance: 60) Presentations: Drinkwater, L.E. 2009. Nutrient cycling processes in legume-based systems. 16th International Congress on Nitrogen Fixation, Big Sky, Montana, June 2009. Drinkwater, L.E. 2009. Evaluating cover crop performance in the field. Cornell Organic Cropping Systems Field Day. August 2009. Van Zyl, B. 2009. Warm season cover crops: field demonstration. Cornell Organic Cropping Systems Field Day. August 2009. Drinkwater, L.E. 2009. Managing biological N fixation in grain rotations. Cornell Organic Cropping Systems Field Day: Grain Systems. November 2009. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
1. Our work with the warm season cover crops is producing novel information on the interplay between biomass production, N fixation rates and the ability of these various species to suppress weeds. We are finding that in general, mixes that include a legume and non-legume species are most effective at suppressing weeds while also achieving at least moderate amounts of fixed N. The most interest mixes, which are already being tested by a few growers who have seen these plots during various field days are the clover-buckwheat mixes. These have the advantage of suppressing weeds as the buckwheat grows very quickly. Then the buckwheat can be mowed at flowering allowing the clover to grow very rapidly before cold weather sets in. This year, we were able to test some of these mixes in growers fields. We will be using these findings in a workshop we are organizing for organic growers to be held in January 2010. 2. The outcomes of the Sustainable Ag. Scholars Program spanned a range of changes in knowledge and actions. We piloted an educational model, the Sustainable Agriculture Scholars Program, linking research in organic agriculture to experiential learning activities for summer undergraduate employees in 2007 and 2008. Our objectives were to: (1) further student understanding of sustainable agriculture research, (2) increase student interest in sustainable agriculture careers, and (3) use community service as a vehicle for learning. The three learning environments were on-farm and laboratory research settings, weekly meetings and field trips to discuss research and observe farming practices, and a service-learning project. We collected feedback from participants through a post-program focus-group style evaluation in Year 1 and pre/post individual evaluations with participants and a non-participant comparison group in Year 2. Students learned about linkages between research and practice within all environments. Farm visits were the primary learning site, specifically through observations of sustainable agriculture practices related to lab work and interactions with farmers. Students described how farm visits made lab work relevant; however, there were few instances describing how lab work was relevant to farming communities. Our preliminary findings from this pilot study suggest that participation in the program led to increased interest in sustainable agriculture careers and increased desire to pursue research in some students. The outcomes of this pilot study have been published in the Journal of Natural Resources and Life Sciences Education.

Publications

• Grossman, J. M., M. Patel, and L. E. Drinkwater. 2009. Enhancing Undergraduate Agro-Ecological Laboratory Employment through Experiential Learning. Journal of Natural Resources and Life Sciences Education. In press.

Progress 09/01/07 to 08/31/08

Outputs
OUTPUTS: 1. Two screening experiment were conducted in 2008 comparing 8 different legumes as monocultures and in mixes with 5 non-legume species. These potential cover crops target the niche in vegetable rotations following early season vegetables. These cover crops would be planted in early to late July and would grow for 2-4 months. We are focusing on these warm season covers based on feedback we received from organic vegetable farmers. Several species included in the experiment were suggested by farmers who have experimented with them intermittently and felt that they were worth further study. Sample analysis began in November 2008 and will continue into 2009. A second follow up experiment is planned for 2009. 2. The rhizobial DNA from soybean and clover root nodules has been analyzed. The extracted soybean DNA was compared to soybean reference strains were obtained from the United States Department of Agriculture (Beltsville, MD) and included type strains and accessions of Bradyrhizobia japonicum inoculating soybean: USDA 31, USDA 76, USDA 94, USDA 110, USDA 122, USDA 123, and USDA 442. Both the soybean and clover strains were analyze using rep-PCR using BOX primers, nif-H gene PCR-RFLP, and standard phenotypic characterization of cultured isolates. A manuscript is currently in preparation. 3. Collaborative legume cover crop trial: In early fall of 2006, we collaborated with a cover crop trial that had been established in July 2006 to evaluate how two warm season green manures performed in monoculture and as intercrops with grasses. The treatments included two legume monocultures (forage soybean and cowpea) and intercrops of these legumes with each of two grass species (Japanese millet and sorghum sudangrass) for a total of 6 treatments. We have completed data analysis and are preparing a manuscript for publication. 4. We continued Sustainable Agriculture Scholars program for a second year. Three Cornell undergraduates were recruited in a competitive process to be Scholars in summer of 2008. These students were engaged in our research activities and participated in weekly structured meetings as in 2007, with some slight modifications. They also carried out a service-learning project 1 day each week with an agriculturally-focused host of their choice. Hosts this year included: 1) the Cornell student organic farm 2) the Tompkins County children's garden and 3) the Drinkwater laboratory. We expanded the options this year to include research in order to accommodate one student who was really interested in laboratory research. A second focus group evaluation was organized and facilitated by our collaborators in the Education Department. Two presentations on this program were given and a manuscript has been submitted to the Journal of Natural Resources and Life Sciences Education. PARTICIPANTS: Laurie Drinkwater: Laurie is the PD and in addition to her role in helping with the planning and implementation of the overall project, she is analyzing the N fixation results from the first cover crop experiment. Julie Grossman: Julie was a Research Associate with the Department of Horticulture until May 2008. She has been working on the Rhizobium characterization and is now an Assistant Professor at North Carolina State University. Ann Piombino: Ann is a Research Technician in the Drinkwater lab. She helped to collect biomass samples from the cover crop experiment, process and analyze the samples. Burtie van Zyl is a graduate student in the Drinkwater lab who is conducting research to develop additional nitrogen fixing cover crops for use in organic rotations. Kelley McCrudden, Lindsay O'Hara, Benjamin Plowe are undergraduates who participated in the Scholars Program in Summer 2008. Partner organizations: Northeast Organic Farming Association, New York, PO Box 880 Cobleskill, NY 12043-0880; Farmscape Ecology Program, Hawthorne Valley Farm, Ghent, NY 12075, many collaborating farmers. TARGET AUDIENCES: In addition to the undergraduates who participated in the Sustainable Ag. Scholars Program, the farmers who serve on the advisory committee and the farmer research collaborators we reached additional organic farmers through the workshop we presented at the NOFA meeting and a presentation on nitrogen fixing cover crops to growers in the Hudson Valley. The information resulting from this research has been included in a series of columns we produced for publication in various newsletters targeting farmers and extension educators (Northeast Organic Farming Association, New York, Cornell Small Farm Center, other NY extension newsletters). These newsletters target farmers in the northeast, particularly New York, including organic as well as conventional family farms. Workshops: What Can Legumes do for YOU Understanding Biological Nitrogen Fixation from the Ground Up. 2008 Conference of the Northeast Organic Farming Association, New York. January 2008. Presentations: Drinkwater, L.E. Managing nitrogen fixing cover crops in organic vegetable systems. Twilight meeting of Hudson Valley Ecological Farming group. July 2008. Grossman, J.M., Patel, M., and Drinkwater L. Promoting Sustainable Agriculture Careers for Undergraduates through a Collaborative Experiential Learning and Research Program at Cornell University: The Sustainable Agricuture Scholars Program. Association for the Advancement of Sustainability in Higher Education Conference, Oral presentation, Nov 9-11, 2008, Raleigh N.C. Grossman, Julie M., Meagan E. Schipanski, Maya R. Patel, and Laurie E. Drinkwater. The Sustainable Agriculture Scholars Program: Enhancing students' summer agroecological laboratory employment through structured experiential learning and reflection. Ecological Society of America Annual Meetings, Aug 3-8, 2008, Milwaukee, WI. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
1. Our work with rhizobia isolates has shown that rhizobia isolated from conventional field nodules with either continuous corn or almost continuous corn have extremely reduced diversity compared to the isolates collected in organically managed fields. Fields with a diversity of legumes in the rotation seem to have greater rhizobia diversity, perhaps due to the background of inoculant rhizobia added in the rotation. It appears that the majority of strains in nodule community are most similar to B. japonicum. Early results for red clove indicate that these inoculants are also diverse, however a few of the strains matched closely with the inoculants. The preliminary take home message from this work is that organically managed fields support more diverse communities of symbiotic N fixing microbes and that the microbes colonizing nodules are mainly derived from the soil rather than the inoculants. 2. The outcomes of the Sustainable Ag. Scholars Program spanned a range of changes in knowledge and actions. We developed and piloted an educational model, the Sustainable Agriculture Scholars Program, which linked scientific research in organic agriculture to structured experiential learning activities for summer undergraduate employees in 2007 and 2008. Our objectives were to: 1) further student understanding of the role of research in supporting sustainable agriculture, 2) increase student interest in agricultural career options, and 3) use community service as a vehicle for learning. Three students were selected for the summer program in each year. The three major learning environments were on-farm and laboratory research settings, structured weekly meetings and field trips to discuss research and observe farming practices, and a facilitated service-learning project with an agricultural organization. We collected student feedback through a post-program focus-group style interview with a third party in years one and two, and added a pre-program interview and a student comparison group in year two. Students reported learning about linkages between agriculture research and practice within all three environments, with farm visits being the primary site of this learning, specifically through observations of sustainable agricultural practices related to their lab work and interactions with farmers. Though students described ways in which farm visits made lab work seem more relevant, there were few instances describing how the lab work was relevant to the farming community. Four out of the six students reported increased interest in agricultural careers as a result of participating in the Program; three reported increased desire to pursue agricultural research. Service project discussions demonstrated students' sense of ownership and satisfaction about contributing to their community. This evaluation demonstrates the potential for this and other similar programs to foster interest in sustainable agriculture and agriculture research for undergraduates.

Publications

• No publications reported this period

Progress 09/01/06 to 08/31/07

Outputs
OUTPUTS: Activities 1. In 2007, we completed the first set of experiments in 17 on-farm grain fields in order to measure how biological N fixation (BNF) varied across soil fertility. The six treatments were as follows: Annuals--1) field pea (Pisum sativum), 2) oat (Avena sativum); Perennials- 3) red clover (Trifolium pratense), 4) orchard grass (Dactylis glomerata); Mixes-5) annuals intercropped, and 6) perennials intercropped. The aboveground biomass was sampled in fall 2006 and spring 2007. BNF results from the fall sampling were analyzed. The legumes grown in mixtures with a grass maintained higher rates of nitrogen fixation than legumes grown in monoculture. Perennial red clover fixed more nitrogen than annual field pea. 2. We have isolated and purified rhizobial DNA from soybean and clover root nodules that were collected from replicated field trials on 4 organic farms and two conventional farms. This DNA has been used to investigate if a) there are differences in rhizobia populations across a wide spectrum of organic systems and management, and b) if the rhizobia in the nodule is from indigenous non-inoculant populations of rhizobia in the soil, or from inoculant added at the time of planting. Techniques currently being used to answer these questions include rep-PCR using BOX primers, nif-H gene PCR-RFLP, and standard phenotypic characterization of cultured isolates. We will discuss these projects and recruit new farmers for involvement during a workshop event on nitrogen fixation which we have organized for this January, 2008 annual NOFA meeting. 3. In early fall of 2006, we collaborated with a cover crop trial that had been established in July 2006 to evaluate how two warm season green manures performed in monoculture and as intercrops with grasses. The treatments included two legume monocultures (forage soybean and cowpea) and intercrops of these legumes with each of two grass species (Japanese millet and sorghum sudangrass) for a total of 6 treatments. Biomass samples were collected and analyzed for 15N abundance. In early 2007 a pot study was conducted to determine the B values for the two legume species. Results from this experiment are currently being analyzed. 4. A major activity of the past year was the initiation of the innovative Sustainable Agriculture Scholars program. Three Cornell undergraduates were recruited in a competitive process to be Scholars in summer of 2007. These students were directly involved in on-farm field and lab work within the project boundaries and participated in weekly structured meetings to critically discuss and learn about the research process and the larger context of sustainable agriculture. They also carried out a service-learning project 1 day each week with an agriculturally-focused host of their choice. Hosts included 1) the Cornell student organic farm, (2 students) and 2) the Tompkins County Master Composters Program. A focus group evaluation was organized and facilitated by our collaborators in the Education department in preparation for a published manuscript on the Sustainable Agriculture Scholars program so that others can replicate our program. PARTICIPANTS: Laurie Drinkwater: Laurie is the PD and in addition to her role in helping with the planning and implementation of the overall project, she is analyzing the N fixation results from the first cover crop experiment. Julie Grossman: Julie is a Research Associate with the Department of Horticulture. She has been working on the Rhizobium characterization and coordinated the scholars program this past summer. Ann Piombino: Ann is a Research Technician in the Drinkwater lab. She helped to collect biomass samples from the cover crop experiment, process and analyze the samples. Abha Gupta, Lauren Maghram and Suzanna Konecky are undergraduates who participated in the Scholars Program in Summer 2007. TARGET AUDIENCES: The target audience that we reached this past year includes the undergraduates who participated in the Sustainable Ag. Scholars Program and the farmers who serve on the advisory committee and who are collaborating in the on-farm research components. We expect to broaden our audiences considerably during the coming year.

Impacts
Outcomes/Impacts 1. Our work with rhizobia isolates has increased our knowledge about the variation in rhizobia populations found in root nodules across organic farming systems that varied in years of organic management from 0 - 20 years. Rhizobia populations varied across the three farms from where soybean nodules were taken. Isolates from different farms were found to be only 50-60% similar, while rhizobia within a field were shown to be 75-95% similar to each other. At this point, we have no reason to believe that nodules that are formed on the lateral roots of the plant have different bacteria types within them than do nodules on the central crown portion of the root As a whole, these results demonstrate that management may have a significant effect on population structure and thus also on amount of nitrogen fixed. We will soon have data allowing us to determine source of rhizobia, specifically if it was originally from the inoculant that organic farmer rely upon to ensure that an adequate population of rhizobia is available for nodulation at the time of planting. 2. The outcomes of the Sustainable Ag. Scholars Program spanned a range of changes in knowledge and actions. The three students in the program gained knowledge not only about laboratory and field research methods and data analysis, but also about the larger context of real world sustainable agriculture issues. We did this by organizing a weekly seminar in which the students learned about: organic farming practices (especially soil management) by touring working organic farms and talking with farmers, the role of extension in agricultural development through discussions with the Cornell Small Farms Program administration, and agricultural career options by hosting a workshop with the Cornell Career Services center. The focus group results demonstrated that each of the students had either changed career paths or become more interested in agricultural careers in sustainable agriculture, including research and extension. The impact of our program went beyond the three students involved, however, as many other lab groups with summer employees have shown interest in developing similar programs to help increase student excitement about their day-to-day laboratory activities, and increase awareness of the applied nature of agricultural research. Specific actions included 2 out of the 3 students continuing to be engaged in research on organic farming systems in the Drinkwater lab into the school year, and all students taking classes that were related to sustainable agriculture the following semester. The published manuscript which we will be working on in year 2 will make the findings of this experiential learning approach available to other laboratories to replicate at a larger scale.

Publications

• No publications reported this period