Learning from farmer innovation in nitrogen fixation for improved nutrient management on organic farms

2008 Annual Report for LNE07-252

Project Type: Research and Education
Funds awarded in 2007: $99,108.00
Projected End Date: 12/31/2011
Region: Northeast
State: New York
Project Leader:
Julie Grossman
Cornell University
Laurie Drinkwater
Cornell University

Learning from farmer innovation in nitrogen fixation for improved nutrient management on organic farms


We held our first workshop on nitrogen fixation management in Jan 2008. Twenty participants attended and of those, 8 evaluated the workshop. The evaluations indicated that the material was presented in an effective manner and was interesting (100%) and 88% agreed that the information would be beneficial in their work. A second workshop was held at a twilight meeting in the Hudson Valley with 30 growers in July 2008. We also launched our newsletter column this year which was published in several newsletters and reached a wide audience of thousands of growers in the northeast. Our first round of farmer interviews was completed and we are revising the interview tool in anticipation of completing an additional 18 interviews in 2009. Finally, we completed on-farm measurements of biological N fixation on 10 farms and will continue with an additional group of farms this growing season.

Objectives/Performance Targets

1. Over 2000 growers and those working as grower educators will read answers to farmer questions on green manure management for BNF in our column

2. Overall, the 60 farmers trained in green manure management for BNF will act as informal educators to another 60 farmers who were not directly trained

3. Of the 50-60 farmers involved as workshop attendees, collaborators, or advisors, 25 will adjust their management of green manures within 6 months of project completion.


1. Newsletter column: Several newsletter columns were published during 2008. We launched the “Ask Vicki Vetch column in January 2008 with an announcement soliciting grower questions on cover crops in the NOFA-NY newsletter. Vicki Vetch is now being carried by three newsletters: 1) The Small Farms Quarterly is mailed to 27,000 small farms in several states and is also available on-line. 2) The NOFA-NY newsletter ‘Organic Farms, Folks, and Foods’ is distributed to all NOFA-NY members and 3) The Cornell Cooperative Extension newsletter VegEdge is distributed to farmers in Western NY, including Ontario, Yates, and Monroe counties. In addition to the first call for questions, we have published two articles which are presented as a response to a specific question received by Vicki Vetch. Topics covered in 2008 include ‘Red and White Clover Close-up’ and ‘New Vetch Varieties Snap-shot’. The winter 2009 issue will include an answer to a challenging question about cover crop management and nutrients and will include a corresponding feature article.

2. Workshops- farmer and extension educator training: Our workshop, entitled What Can Legumes do for YOU? Understanding Biological Nitrogen Fixation from the Ground Up!, presented during the Northeast Organic Farming Association conference January 25th, 2007 was attended by 20 participants. The half-day workshop was taught by 3 experienced farmers, and the SARE project coordinators (Julie Grossman and Laurie Drinkwater). The program covered various strategies of legume cover crop use, and introductory information about the ecology and biology of biological nitrogen fixation in the field. We received very good evaluations from this first workshop. We also gave a presentation on “Managing legumes to optimize biological N fixation” to 30 growers in the Hudson Valley region, July 7th, 2008. This was an informal twilight meeting. This group was particularly interested in summer cover cropping options. One grower contacted us after the presentation to say that he was so excited about the forage soybean cover crop, he tried to get seed for planting but could not find any distributor that had seed. We are finding that access to legume seeds, particularly quality organic certified seeds is a significant barrier that farmers face. Overall, our workshop efforts have generated a lot of interest and we will carry out additional workshops in 2009 using the model we developed for the NOFA workshop.
Feedback from the first SARE-sponsored workshop at the 2008 NOFA meeting:
The most useful features of the workshop for me were:
• “The biology of N fixation: So helpful to understand the biology of this relationship between species”
• “Eero’s presentation: Very well done; would be nice to have a handout”
• “Interactive portion: Interacting and participation always yields rich learning for me. Well done. Thanks for mixing us and addressing (or allowing us to address) these questions”
• “Information respective to crops and rotations”
• “The talk about ecology”
• “The New Hampshire farmer’s presentation. Thorough and excellent slides”
• “Networking/talking with other farmers”
• “The farmer’s actual use of cover crops and the gaps in their systems that require research or further evaluation to fill.”
• “Listening to the experiences of others”
• “Specifics about N-fixation and nodulation”
• “All of it was a good mix of general and specific information as well as the scientific underpinning”

Will the information you learned today change your management of soil fertility and use of nitrogen-fixing green manures? If so, list one specific change you will consider using, at least on a trial basis, in the next year.

• “I will encourage people in NYC to plant winter legumes, and try using living mulches between crops. Also, I will work to bring workshops on cover cropping with legumes to NYC gardners”
• “If I can find Tony’s (Potenza’s) N-producing radish, I’d like to try that”
• “I’ve used legumes mainly for animal feed. I might start looking at them for soil health.”
• “Yes, buckwheat for summer planting”
• “Yes, I will learn better ways to handle inoculant, I will look into nodules more to see if there is competition between bacteria; I will attempt different cover crop schedules”
• “I might try Austrian field peas”
• “White clover alleys in my garden; and maybe try them under my Brussels sprouts”

3. On-farm survey plots to assess nitrogen fixation and grower interviews: In 2007 we established 10 plots on a total of 8 working farms for assessment of nitrogen fixation. Preliminary contact was made with 40 vegetable farms from the NOFA list, followed up with a personal phone-call. A total of 10 farms planting winter legumes intercropped with a non-legume were identified. The eight farms chosen for plot establishment are listed under ‘collaborators’ in the beginning of this report. Most farms planted hairy vetch intercropped with rye, oats, or winter wheat. On each farm, four replicate plots in one or more field were established. Within two weeks of farmer seeding, each plot was weeded accordingly to create three sub-plot treatments including a) legume only, b) non-legume reference plant only (rye, oats or wheat), and c) farmer practice (both legume + non-legume). Plots were sampled in spring 2008 a15N abundance. We received the data from these samples and are in the process of analyzing the results. Our plan is to provide this information to our collaborating farmers in a way that gives them information on there specific field while also providing them with an overview of the N-fixing rates we have found across the full range of vegetable farms. We also carried out the first round of the grower interview with 7 farmers in the Hudson Valley region and identified 4 farms that will collaborate with these on-farm trials during the 2008 growing season. In the fall of 2008, 5 farms in the Finger Lakes area were identified as growing fall seeded cover crops and 4 sets of micro plots were set up. Due to the unusually cold fall weather, plots were not set up in all the fields. In early 2009, more plots will be set up on 2-3 more farms.

Impacts and Contributions/Outcomes

• The results from our first 7 farmer interviews were extremely enlightening and point to several limitations that farmers face in their management of nitrogen fixing cover crops. One issue that has come up is the access to quality cover crop seed. A second issue is recommendations for seeding rates, etc. We found that many growers use SARE’s publication the Northeast Cover Crop Handbook (Sarrantonio, 1994) as a reference for seeding rates. We expect that when we have completed these interviews, we will have a wealth of information that will be helpful in promoting better cover crop management in the northeast.
• Hundreds of growers have been able to access information on nitrogen fixing cover crops through our newsletter column which is structured to publish responses to specific, grower-generated questions. Furthermore 40 growers who have participated in our workshops have learned how they can manage the biology of legumes and have also heard about practical tips for managing cover crops from expert growers. A significant proportion of these growers and extension educators plan to take action as a result of what they learned in these workshops.
• Over the course of this first year, as we establish monitoring plots in farmer’s cover crop fields, we find that there is a very strong interest in the actual measurements on nitrogen fixation we are making. Farmer’s are extremely curious to know how much N they are actually getting from these covers. This information will be included in our next round of workshops. We also plan to publish a Vicki Vetch article summarizing these findings of actual on-farm fixation rates from this project and other earlier projects. Also, we anticipate that we will be able to use this information in creating management guidelines for nitrogen fixing cover crops in the future.


Carol MacNeil

[email protected]
Senior Extension Educator /Vegetable Specialist
Ontario County Coop Extension Association
480 N. Main St.
Canandaigua, NY
Office Phone: 5853943977
Greg Swartz

[email protected]
Interim Executive Director
Northeast Organic Farming Association of NY
PO Box 880
Cobleskill, NY 12043-0880
Office Phone: 8457968994
Website: www.nofany.org