Nutrient management on organic vegetable farms: A research and education program for sustainable soil fertility management in southern New England

Final Report for LNE09-285

LNE09-285 (project overview)
Project Type: Research and Education
Funds awarded in 2009: $148,375.00
Projected End Date: 12/31/2013
Region: Northeast
State: Massachusetts
Project Leader:
Dr. Beth Hooker
Email
Hampshire College
Co-Leaders:
Beth Hooker
Email
Mount Holyoke College
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Project Information

Summary:

The seventeen farmers who participated in the on-farm research in 2010-2011 received detailed soils test results and fertility recommendations for 65 different fields, sampled 3 times per season. Many of the farms were doing well with their N management; however, 30% of the fields sampled indicated excess N in the mid-season. Also, the phosphorus levels were generally within or below the optimal range, although, again, about 30% of fields were in excess. We showed that the use of hoop houses had led to extremely high N and P levels, in all 4 sampled. These results suggest that as farmers use more hoop houses to extend the growing season, more work needs to be done with regard to reducing N and P inputs. The farmers with excess N and P levels were generally surprised, indicating that they would alter future applications of soil amendments as a result.

We have identified a need for soil tests that are specifically targeted to the needs of organic vegetable growers. One test that shows much promise for organic farmers is the Illinois Soil N Test (ISNT). The ISNT analyses soil for amino-sugar N, a fraction of soil N that is easily mineralizable and that may become available for the crop during the growing season (Khan et al., 2001). We assessed the ISNT on over 60 fields with biologically-based inputs with a variety of compost and manure application histories to ensure a range of potential soil N supply capacity. We found a significant, positive relationship between the ISNT values and N mineralization and organic matter content, and we expect that this will become a valuable tool for organic farmers in the region.

We held two regional workshops, aimed at education about sustainable soil management methods and led by farmer-peer educators. All 25 farmers who participated in the workshops received educational materials to optimize their N and P inputs, using a combination of soil amendments, green manures, organic C management, and organic fertilizers.

Introduction:

Organic farmers typically use manures and composts to address their soil fertility needs.   The addition of organic materials has obvious benefits to soil health, such as increased soil aggregation, water holding capacity, and organic matter content. In turn, improvements in soil aggregation are intimately tied to important soil properties such as protection of soil organic matter (Tisdall and Oades, 1982), erosion control (Barthes and Roose, 2002), nutrient cycling (Linquist et al., 1997; Wang et al., 2001), microbial community structure (Bossuyt et al., 2001), and regulation of water flow (Parmelee et al., 1990). Such improvements provide the foundation for organic agriculture. Unfortunately, while many farmers believe that the slow-release nature of composts minimizes the problem of nutrient leaching or runoff, small amounts of compost have been shown to cause excessive amounts of available soil P and soil nitrate. A SARE-funded survey conducted by Dr. Tom Morris (2004) suggested that organic vegetable growers have difficulties maintaining optimum nutrient levels, highlighting the need for better nutrient management practices on organic farms.

Understanding the nutrient content of biologically-based nutrient inputs and predicting the amount of available N and P after repeated organic additions is a perennial problem, especially due to the lack of specific soil testing procedures created for these conditions. There is a need for soil tests that are specifically targeted to the needs of organic vegetable growers. In this study, we tested the Illinois Soil N Test (ISNT) to assess its promise for for organic farmers. The ISNT analyses soil for amino-sugar N, a fraction of soil N that is easily mineralizable and that may become available for the crop during the growing season (Khan et al., 2001). The test has been calibrated for conventionally-grown corn in Illinois (Khan et al., 2001), New York (Klapwyk and Ketterings, 2006), and Connecticut (unpublished data). It has also been shown to predict N responsive sites where liquid or composted dairy manure is applied to corn agroecosystems (Klapwyk et al., 2006). We assessed the ISNT on over 60 fields with biologically-based inputs with a variety of compost and manure application histories to ensure a range of potential soil N supply capacity. We found a significant, positive relationship between the ISNT values and N mineralization and organic matter content, and we expect that this will become a valuable tool for organic farmers in the region.

We assessed soils mid-season over two growing seasons, and we determined that an in-season soil nitrate test would be an excellent tool for organic farmers in their quest for sustainable soil management. This test is most useful when there is reason to believe that N availability may be adequate for crop growth, such as in fields which receive composts or manures (Heckman, 2002). Another excellent application of this test is in the case of double cropping, a common practice in diversified organic farms. Soil nitrate testing measures the carryover N from the previous crop, and N mineralized from organic additions (Heckman, 2002).

The overarching educational goal of this project was two-fold: (1) to provide organic farmers with appropriate tools for sustainable soil management, and (2) to support organic farmers in developing the knowledge and skills they need to assess, manage, and promote sustainable soils on their farms and to their peers. During the first 3 years, we focused our efforts on working with individual organic farmers to assess their nutrient management needs, in conjunction with soil testing for research at these farms. Through our interactions with organic farmers who participated in the first part of the project, we identified farmers to co-lead educational workshops in year 4 for other farmers regarding effective sustainable soil management.  

In April 2013, we conducted a peer-led workshop, which highlighted our findings, as well as allowed farmer-educators to explore the data to make recommendations regarding soil fertility management. The workshop was interactive and designed to (a) uncover the participants’ experiences, knowledge, and concerns in soil nutrient management, (b) increase knowledge about concepts, practices, resources, and ways to adapt soil nutrient management strategies under various conditions, (c) apply their knowledge to address genuine case studies, and (d) identify next steps in achieving optimal soil nutrient levels on their farms.

In December 2013, we offered a second regional workshop. Similar to Workshop I, the workshop was interactive and engaged participants in addressing genuine soil nutrient management challenges. Specifically, the workshop was designed to introduce more advanced concepts and practices in soil nutrient management than were covered in Workshop I, including interpreting results of a range of soil nutrient tests, and developing a soil nutrient budget.

Performance Target:

Performance target: From the 225 organic vegetable farmers who participate in the project, 50 farmers will use individual field records, nutrient management tools, soil testing procedures, and, where applicable, stalk tests to reduce N applications by 30 pounds per acre and P2O5 applications by 30 pounds per acre to achieve optimal levels on 540 acres. These practices will lead to more efficient use of soil amendments linked to crop needs and existing soil fertility, which in turn will reduce the amount of nitrate in groundwater, reduce phosphorus loading to freshwater systems, and decrease the cost of production by $12 per acre for N and $12 per acre for P2O5.

Our work throughout the project was in support of this performance target. The 17 farmers who participated in the on-farm research in 2010-2011 received detailed soils test results and fertility recommendations for 65 different fields, sampled 3 times per season. Many of the farms were doing very well with their N management; however, 30% of the fields sampled indicated excess N in the mid-season. Also, the phosphorus levels were generally within the optimal range, although, again, about 30% of fields were in excess. We showed that the use of hoop houses had led to extremely high N and P levels, in all 4 sampled. These results suggest that as farmers use more hoop houses to extend the growing season, more work needs to be done with regard to reducing N and P inputs. The farmers with excess N and P levels were generally surprised, indicating that they would alter future applications of soil amendments as a result.

During 2010 and 2011, we also assessed the ISNT on the fields with biologically-based inputs with a variety of compost and manure application histories to ensure a range of potential soil N supply capacity. We found a significant, positive relationship between the ISNT values and N mineralization and organic matter content, and we expect that this will become a valuable tool for organic farmers in the region. Use of this test will provide an additional way for farmers to understand their soil fertility and to limit excess nutrients.

There were over 25 farmers who participated in the two workshops, aimed at education about sustainable soil management methods. All who participated in the workshops received educational materials to optimize their N and P inputs, using a combination of soil amendments, green manures, organic C management, and organic fertilizers.

Cooperators

Click linked name(s) to expand/collapse or show everyone's info
  • Alexandra Bell
  • Joe Bonelli
  • George Hamilton
  • Stephen Herbert

Research

Materials and methods:

A. ON-FARM RESEARCH

Our objectives for on-farm research, which we pursued through two approaches, were the following: 1) to assess the ISNT for organic farms by surveying a wide variety of organic farms, collecting soil data, and performing N mineralization incubations (Approach I); 2) to illustrate the utility of the in-season NO3-N test for determining whether soil N availability is adequate for crop production, especially in the case of the common practice of double-cropping on diversified organic farms (Approach I); 3) to assess P levels across a wide number of sites with varying compost or manure addition history to determine the relationship between nutrient management practices and P levels (Approach I); 4) to determine the N mineralization potential of organic soils and explore relationships between N mineralization and the ISNT, NO3-N levels over the growing season, or P levels (Approach I); and 5) to establish winter squash trials on 3-5 organic farms to assess the ability of the ISNT to predict the responsiveness of winter squash to N additions.

 

ON FARM RESEARCH APPROACH I:

 

The research team, with members from the University of Massachusetts, University of New Hampshire and Mount Holyoke/Hampshire College, collected soil samples in 2010 and 2011 from a total of seventeen organic farms in New Hampshire (6), Massachusetts (7), and Connecticut (4). Members of the research team met with farmers to discuss the project plans and to identify 3-5 fields appropriate for sampling. Soils were collected from three sampling dates (early, mid-, and late season) and were analyzed at the University of Maine soil testing laboratory. Research team members discussed results from the 2010 growing season with farmers in early spring 2011, so that their nutrient management approach would reflect current soil conditions. Data from 2011 field research was distributed to the participants in early Spring 2012 to inform their soil fertility decisions.

Work in the third year of the project was focused on analyzing the data collected from over 65 individual fields on organic farms in Connecticut, Massachusetts, and New Hampshire during the first two years of the project. We collected soil samples in early, mid- and late-growing season. In addition to the standard soil test values (e.g., pH, OM, P, K, N), we assessed soils using the Illinois Soil Nitrogen Test (ISNT). We conducted N mineralization experiments at the University of Massachusetts, in order to calibrate the ISNT for soils which receive organic inputs. Much of the sample analysis was completed at the University of Maine analytical laboratory. Because of the variety of soils, management histories, and organic matter content collected from our locations, the UMaine laboratory completed additional analyses using our soils to inform the creation of a new soil carbon dioxide (CO2) analysis that can be used to quantify soil microbial activity (Haney et al., 2008). We continue to work with Bruce Hoskins at the University of Maine to create a publication of the results.

 

ON-FARM RESEARCH, APPROACH II:

In 2011, we established winter squash trials testing the responsiveness of winter squash to N additions, at 4 fields with a range of low to high ISNT values. We chose these sites to sample a range of potential soil N supply capacity. We also chose winter squash, because it was a crop used commonly by the organic farmers. In the original proposal, we indicated that we would use sweet corn, but upon consultation with our farmer participants, we determined that winter squash would be more relevant to typical practices.

By employing three N rate treatments (no N, standard rate, and 1.5 x standard rate), we assessed the efficacy of the ISNT and pre-sidedress soil nitrate test (PSNT) for their ability to distinguish between N responsive and non-responsive winter squash sites. We based the standard N rate on recommendations from soil testing. Sources of N were blood meal at three of the sites and at one site, the source used by the participating farmer. We applied organic sources of phosphorus and potassium (e.g., bone char or potassium sulfate) in levels indicated by soil test values. By including an excessive N rate (i.e., the 1.5 x standard rate), we aimed to ensure that we captured maximum yield where N is not a limiting factor.

We collected soil samples in early and mid-growing season. In addition to the standard soil test values (e.g., pH, OM, P, K, N), we assessed soils using the Illinois Soil Nitrogen Test (ISNT). We conducted N mineralization experiments at the University of Massachusetts. At the end of the season, we collected yield data from each of the replicated plots, from a standard area across sites. Sites with higher ISNT values did not have significant yield response to added N, while those sites with lower ISNT values showed yield responses to added N. These results, which are being included in a peer-reviewed publication, further support the usefulness of the ISNT for organic farmers.

 

B. EDUCATION:

The overarching educational goal of this project was two-fold: (1) to provide organic farmers with appropriate tools for sustainable soil management, and (2) to support organic farmers in developing the knowledge and skills they need to assess, manage, and promote sustainable soils on their farms and to their peers. During the first 3 years, we focused our efforts on working with individual organic farmers to assess their nutrient management needs, in conjunction with soil testing for research at these farms. Through our interactions with organic farmers who participated in the first part of the project, we identified farmers to co-lead educational workshops in year 4 for other farmers regarding effective sustainable soil management.  

A planning meeting was held with the participating farmer educators in winter 2012/2013, along with Beth Hooker (Mount Holyoke College/Hampshire College) and Alexandra Bell (University of Connecticut), to assess learning outcomes associated with participatory research.  

In April 2013, we conducted a peer-led workshop, which highlighted our findings, as well as allowed farmer-educators to explore the data to make recommendations regarding soil fertility management. We are working to analyze the resulting data from the workshop. In December 2013, we offered a second regional workshop. Details of the 2 workshops are included below.

 

WORKSHOP I (April 6, 2013):

Workshop I was facilitated by Beth Hooker, Sandy Bell, and two farmer facilitators (Nancy Hanson and Ryan Voiland). The workshop was interactive and designed to (a) uncover the participants’ experiences, knowledge, and concerns in soil nutrient management, (b) increase knowledge about concepts, practices, resources, and ways to adapt soil nutrient management strategies under various conditions, (c) apply their knowledge to address genuine case studies, and (d) identify next steps in achieving optimal soil nutrient levels on their farms.

The workshop began with participants completing a Pre-Workshop Survey of their current practices, knowledge, and values related to soil nutrient management. Beth Hooker then provided a brief overview of key concepts related to soil nutrient management. A group discussion activity followed in which participants in small groups identified problems or challenges in soil nutrient management they have experienced on their own farms, how they address the problems, and the outcomes of their efforts. The outcomes of this activity were used as the basis for the two farmer facilitators to present additional key concepts and resources to the participants. Each farmer facilitator then presented a case scenario reflecting genuine challenges associated with soil nutrient management on organic produce farms. One scenario addressed converting to organic a previously conventionally farmed field, and the other scenario addressed issues with a field that had been fallow for many years. The participants worked in groups to identify what data they needed to know in order to offer recommendations, worked with the actual data, and then offered recommendations. The workshop concluded with a debriefing of key concepts and practices related to the scenarios, and an all-group discussion of next steps they could take in addressing soil nutrient management on their farms and resources available to assist them.

 

WORKSHOP II (December 13, 2013)

Workshop II was also facilitated by Beth Hooker, Sandy Bell, and two farmer facilitators (Nancy Hanson and Ryan Voiland). Similar to Workshop I, the workshop was interactive and engaged participants in addressing genuine soil nutrient management challenges. Specifically, the workshop was designed to introduce more advanced concepts and practices in soil nutrient management than were covered in Workshop I, including interpreting results of a range of soil nutrient tests, and developing a soil nutrient budget.

The workshop began with participants completing a Pre-Workshop Survey of their current practices, knowledge, and values related to soil nutrient management. Many of the items in this survey were similar to those in the Pre-Workshop Survey for Workshop 1. Beth Hooker provided an overview of the NESARE research project, and presented data from study participant sites to illustrate key concepts and practices related to how and when to test soil, how to interpret results, and how to apply the results in making soil management decisions. Farmer facilitator, Ryan Voiland, then led the participants through a case scenario illustrating steps in developing a soil nutrient budget on a field that is being converted from conventional to organic practices. Following, Nancy Hanson led the participants in a case scenario in which they needed to account for green manures in developing a soil nutrient budget. For each scenario, participants used worksheets and a variety of text and web-based resources to address completing the soil budgets. Beth Hooker facilitated a wrap up of the workshop by sharing a variety of resources available to organic farmers in assessing soil nutrient levels and developing soil nutrient management plans for their farms.

Pre-Workshop Survey Data Analysis

Sandy Bell created an SPSS database of participant responses to the Workshop I Pre-Workshop Survey and the Workshop II Pre-Workshop Survey. Descriptive statistics were generated for all numerical response items and qualitative written responses were analyzed for themes.

In the original project proposal, we planned to assess changes in knowledge, values, and behaviors related to soil nutrient management among participants who attended both workshops. However, among the 11 Workshop I participants and the 12 Workshop II participants, only two individuals attended both workshops. Therefore, we were not able to conduct statistical analyses of changes in attributes among participants from the first workshop to the second.

Research results and discussion:

This section includes the milestones, as included in the original proposal, with responses to how those milestones were addressed. In addition, there are results and discussion sections for the on-farm research and for the education components of the project.

ON-FARM RESEARCH MILESTONES:

  • Milestone 1: A group of 25 organic vegetable growers will use two new nutrient management planning tools to assess their fertility needs: (1) an NRCS-compliant tool which utilizes a combination of spreadsheets for vegetable farmers to develop nutrient management plans; (2) a web-based program for predicting soil organic matter and P changes from applications of manure and compost. Participating farmers will gain critical insights about their soil fertility and employ modified nutrient management strategies as a result.   Data from 2010 and 2011 was shared with the participating farmers. We held a series of meetings to analyze the site-specific data. We decided on this approach in order to maximize use of data and to engage farmers more fully in the data analysis.

  • Milestone 2: Among the group of 25 organic vegetable farmers, 5 farmers will participate in an on-farm research trail to test the responsiveness of sweet corn to N additions. We will assess the efficacy of the ISNT, PSNT, and the cornstalk nitrate test for their ability to distinguish between N responsive and non-responsive sweet corn sites. Farmers will gain an appreciation for research design and data collection and will be active participants in the research.   Established field trials, using winter squash instead of sweet corn. The change in crop better reflects farmers’ crop choices (sweet corn is a minor crop for the organic vegetable growers in this study). Established field trials on 4 farmers’ fields. Analyzed data will be included in a peer-reviewed journal article, aimed at establishing the utility of the ISNT for organic farmers.

  • Milestone 3: Before the second growing season, the group of 25 organic vegetable growers will use data from the previous year in the nutrient management tools. Farmers will adjust their nutrient management approach to reflect current conditions of their soils. The group of 17 organic farmers received their data from the previous year. Members of the research team met with and answered questions about the data with farmers in New Hampshire, Connecticut and Massachusetts.

  • Milestone 4: During the second year of on-farm research trials, the continuing group of 5 organic growers will participate in the data analysis. After collecting 2 years of data on the efficacy of the ISNT, PSNT, and the cornstalk nitrate test for their ability to distinguish between N responsive and non-responsive sweet corn sites, we will work together to interpret the data. Peer educators led discussion of data from field trials as part of farmer workshops in 2013. This work continued with the second regional nutrient management workshop in Fall 2013,where farmers worked on examples from the two farmer educators’ fields.

 

ON FARM RESEARCH OBJECTIVES, RESULTS AND DISCUSSION

 

OBJECTIVE 1: To assess the ISNT for organic farms by surveying a wide variety of organic farms, collecting soil data, and performing N mineralization incubations; and to determine the N mineralization potential of organic soils and explore relationships between N mineralization and the ISNT, NO3-N levels over the growing season, or P levels (Approach I)

During 2010 and 2011, we assessed the ISNT on over 60 fields with biologically-based inputs with a variety of compost and manure application histories to ensure a range of potential soil N supply capacity. We found a significant, positive relationship between the ISNT values and N mineralization and organic matter content, and we expect that this will become a valuable tool for organic farmers in the region. We have included data from 2010 to illustrate the trends (Fig. 1 and 2). Data from 2011 is similar (significant, positive relationships), and will be included in peer reviewed journal article.

 

We did not find significant (or meaningful) relationships between ISNT and NO3-N or P levels (data not shown).

 

OBJECTIVE 2: to illustrate the utility of the in-season NO3-N test for determining whether soil N availability is adequate for crop production, especially in the case of the common practice of double-cropping on diversified organic farms (Approach I);

 

During 2010 and 2011, we sampled all sites mid-season for NO3-N, to assess mid-season availability. Figure 3 shows data from 2010 (trends were similar for 2011 and will be compiled for peer reviewed paper). About 20% of the values indicated that no additional N fertilizer was needed mid-season (i.e., values between 25-35 ppm). There were many sites where additional N was needed (about 50%). About 30% were in excess of plant need, suggesting the possibility of excess N leaching from the sites. Extremely high levels of NO3-N were found in hoop houses, suggesting a need for better management in those settings, especially when growing leafy greens. Overall, the results support the utility of having a mid-season evaluation for organic farmers to meet nutrient and plant management goals.

OBJECTIVE 3: to assess P levels across a wide number of sites with varying compost or manure addition history to determine the relationship between nutrient management practices and P levels (Approach I);

In 2010 and 2011, we sampled sites in early season for PO4. We did not find significant (or meaningful) relationships between PO4 levels and NO3-N, NH4-N, N mineralization or ISNT values. We found extremely high PO4 values in hoop houses, suggesting that these sites were accumulating nutrients and are in need of more active fertility management to avert environmental consequences. Below are two figures showing PO4 values, one with the “outliers” from the hoop houses, and then one with them removed (Fig. 4-5). In the second figure, data show that about two thirds of the values were either within the optimal range for plant growth or below it. The other third of the fields had PO4 levels that exceeded the optimal range, indicating management practices that allow for PO4 accumulation. Additional analysis of 2010-2011 data will be included in a peer-reviewed journal article.

OBJECTIVE 4:   to establish winter squash trials on 3-5 organic farms to assess the ability of the ISNT to predict the responsiveness of winter squash to N additions (Approach II).

In 2011, we established winter squash trials testing the responsiveness of winter squash to N additions, at 4 fields with a range of low to high ISNT values. We chose these sites to sample a range of potential soil N supply capacity. We also chose winter squash, because it was a crop used commonly by the organic farmers.

At the end of the season, we collected yield data from each of the replicated plots, from a standard area across sites (Figs. 6-8). At one of the Hampshire College Farm sites, field crews harvested the field for CSA distribution before yield data could be collected; thus we only have three sites. Extreme rainfall from Hurricane Irene (ca. August 29, 2011), affected crop yields across all sites. Sites with higher ISNT values did not have significant yield response to added N, while those sites with lower ISNT values showed yield responses to added N. These results, which are being included in a peer-reviewed publication, further support the usefulness of the ISNT for organic farmers. However, additional field trials are necessary to calibrate the ISNT model.

 

EDUCATION MILESTONES/RESULTS AND DISCUSSION

  • Milestone 5: The first regional nutrient management workshops will be offered in January of year 3 for farmers who use organic inputs. Two workshops will be offered in each state for a total of six workshops. Approximately 30-35 farmers will participants in each workshop. From among the core group of 25 farmers who participated in the on-farm research, 12 will serve as peer educators in the first regional workshops, with two farmer educators per workshop. The core group of 12 farmer educators, in conjunction with other project investigators, will help participants identify critical information and resources they need for nutrient management. April 2013. We held one workshop in April 2013, and a second regional workshop in December 2013.

Preface: In our original proposal, we planned to assess changes in farmers’ knowledge, values, and practice behaviors in soil nutrient management that we could attribute to participation in the workshops. We planned for farmers who participated the first workshop to participate in the second workshop as well. Our method of assessment for changes was to be a statistical analysis of differences in participant responses to the pre-workshop survey for Workshop I to the pre-workshop survey for Workshop II. We assumed that we could attribute changes in knowledge, values, and practices, at least in part, to participation in the first workshop. Unfortunately, despite sending email invitations to the 11 Workshop I participants only 2 individuals also participated in Workshop II. Scheduling conflicts appeared to be the primary reason individuals were unable to attend the second workshop. Subsequently, we analyzed the outcomes of the pre-workshop surveys separately and did not run any statistical tests of differences in responses. Following are the outcomes for the Workshop I Pre-Workshop Survey and the Workshop II Pre-Workshop Survey. (Because some notable differences existed in characteristics of Workshop I and Workshop II participants, where applicable, in the description of outcomes for Workshop II Pre-Workshop Survey, we have provided comments about differences solely for descriptive purposes.)

Workshop I.

To assess the knowledge, values, and current practice behaviors of farmers who participated in the first Workshop I, we administered a paper-and-pen survey after participants had arrived and prior to beginning the workshop. Following are the Workshop I Pre-Workshop Survey Outcomes:

  • Participants: Eleven (11) participants total; 9 identified as farmers and 2 were in academic/research positions.

  • Farmer Experience: Though we did not ask for years of farming experience in the Pre-Workshop Survey for Workshop I, based on participant introductions a majority of the farmers were relatively inexperienced, with 5 or less years of experience in farming. One individual had many years (over 20 years) of experience.

  • Farm Types: The farmer participants worked at relatively small-scale levels. Average acres in operation during 2012 was 5.7 (SD = 6.5), with a range from 0-15 acres. Five (5) farmers identified their operations as organic, 2 as sustainable, and 2 as organic and sustainable. None of the operations were certified organic.

  • Soil Nutrient Management Knowledge: Overall, participants were knowledgeable about definitions of key concepts in soil nutrient management. A subgroup (6 or 10) mixed up the definition of the PSNT and ISNT tests; with that exception, all the participants the questions correctly. When making decisions about soil fertility, participants ranked the results of soil tests as most important, followed by cost of amendments, use of green manure, and experiences of other farmers. In determining if their soil nutrient management practices have been effective, participants tended to focus on the appearance of plants, followed by crop yield and quality of produce.

  • Soil Nutrient Management Values: Overall, participants valued highly assessing soil fertility on their farms (M = 3.67 on 1-4 scale, SD = .50), and consider results of soils tests when making soil fertility decisions (6 used soil testing in the past 2 years, 2 did not, and 3 did not reply.) In order of importance, participants identified reduced crop yield, reduced soil health, and excess N or P runoff as the most important consequences of not assessing soil fertility

  • Soil Nutrient Management Behaviors: Participants who used soil testing tended to use university soil test services (n = 6) and get soil tested primarily in the spring (n =3), and secondarily in the fall (n = 2). A subset of farmers (n = 3) also used soil-testing services from independent vendors. None of the farmers indicated using the PSNT or cornstalk nitrate tests. One (1) farmer indicated using the ISNT and 1 farmer a mid-season soil test. All the farmers who use soil tests have not followed recommendations at one point. The two factors that had the biggest influence on their not following the recommendations were the cost to implement the recommendations and the timing—with the recommendations too late to implement.

  • In response to the open ended-question, “What is the biggest concern you have regarding sustainable soil management practices on your farm?” participants tended to be concerned about soil pH, long-term soil health, and impact of cost of amendments on financial income.

 

  • Milestone 6: The second regional nutrient management workshops will be offered to the farmers who participated in the first workshops, in the manner described under Milestone 5. The second workshops will build upon the first. Participants will be involved in interpreting the results of the on-farm research projects and trials from years 1 and 2 and in developing a customized soil nutrient management plan.

 

Workshop II.

Prior to the start of workshop II, we administered a paper-and-pen survey that was very similar to the Workshop I Pre-Workshop II survey. Following are the Workshop II Pre-Workshop Survey Outcomes:

  • Participants: Twelve (12) participants total. All participants were farmers, and 11 indicated they had been active in vegetable production in 2012. Two (2) of the 12 individuals also participated in the first Workshop I.

  • Farmer Experience: Compared to participants in Workshop I, participants in Workshop II were more experienced. They had an average of 6.25 years farming experience (SD = 6.68). Six (6) either owned or managed a farm, or both, 3 were employed on a farm full-time, and 1 was a farm apprentice.

  • Farm Types: Compared to participants in the first Workshop I, participants worked on farms that were larger in scale. Average acres in operation during 2012 was 18 (SD = 13.10), with a range from 3-40 acres. Six (6) farmers identified their operations as organic, 4 as sustainable, and 1 as urban garden. Six (6) of the operations were certified organic.

  • Soil Nutrient Management Knowledge: Though the participants in Workshop II had on average more experience than those in Workshop I, they had a wider range in accurate knowledgeable about definitions of key concepts in soil nutrient management. Of the 8 knowledge items, all participants correctly identified only 2 items. Four (4) of the items were correctly identified by 4 or fewer participants. Similar to Workshop I participants, when making decisions about soil fertility, participants in Workshop II ranked the results of soil tests as most important, followed by use of green manure, and productivity or quality of crops in prior seasons. In determining if their soil nutrient management practices have been effective, participants’ responses were very similar to those in Workshop I: they tended to focus on the appearance of plants and crop yield, followed by quality of produce. Noticeably different from Workshop I responses, farmers in Workshop II also identified reduced soil erosion as a important factor in determining if their practices have been effective.

  • Soil Nutrient Management Values: Similar to Workshop I participants, overall, participants valued highly assessing soil fertility on their farms (M = 3.9 on 1-4 scale, SD = .32), and consider results of soils tests when making soil fertility decisions (7 used soil testing in the past 2 years, 3 did not, and 1 did not reply.) In order of importance, participants identified excess N or P runoff as the most important consequences of not assessing soil fertility, followed by reduced crop yield and loss of potential income. Loss of potential income was not among the highest ranked consequences among participant in Workshop I.

  • Soil Nutrient Management Behaviors: Similar to Workshop I participants, participants who used soil testing tended to use university soil test services (n = 7), however this group tended to get soil tested primarily in the fall (n = 4), and secondarily in the fall and spring (n = 2). A subset of farmers (n = 3) also used soil-testing services from independent vendors. Similar to Workshop I participants, none of the farmers indicated using the PSNT or cornstalk nitrate tests. Additionally, none used the ISNT. One (1) farmer indicated using a mid-season soil test.

  • Among the farmers who used soil testing, all of them (n = 8) have not followed recommendations at one point. One of the top two factors that had the biggest influence on their not following the recommendations was the cost to implement the recommendations, similar to farmers in Workshop I. Workshop II participants also identified the recommendations not being consistent with their own experiences and the recommendations not taking into account green manures as influencing their decisions not to follow soil test recommendations.

  • In response to the open ended-question, “What is the biggest concern you have regarding sustainable soil management practices on your farm?” participants tended to have more focused concerns reflecting a wider range of issues than farmers in Workshop I. For example, different concerns included interpreting and prioritizing the various outcomes provided in soil test results, building organic matter and increasing yields in sandy soils, getting consistent results across a variety of farms, soil nutrient leeching in heavy rain, and increasing production in urban garden settings.

 

  • Milestone7: Based on the on-farm research and collaborations, a set of peer-reviewed articles regarding soil fertility with biologically-based nutrient inputs will be submitted. We will also create a set of New England Regional Fact Sheets on Nutrient Management for Farms using Biologically-based Nutrient Inputs. These regional fact sheets will be used by 100 farmers using biologically-based nutrient inputs. Given the necessity to end the grant by December 31, 2013, PIs have committed to completing these milestones during 2014, as part of their professional expectations. Both PIs are expected to write journal articles and outreach publications.

 

 

  • Milestone 8: A follow-up survey of all project participants will be conducted in year 4 to assess current soil management practices and utilization of soil testing resources. From the 25 on-farm participants, we will determine the extent of behavior change and profitability using baseline data from our soil testing database, and the follow-up survey in year 4. Reduction in environmental impacts will be assessed using literature values for N and P loading, on a farm-by-farm basis. We indicated in the recent contract that this work would be completed in Spring 2014, after the project funding has ended

 

Follow-Up Survey

  • We will send a Follow-Up Survey to all farmers who participated in Workshop I, Workshop II, or both, in Fall 2014. The target population is 19 different farmers. The Follow-up Survey will comprise items to assess knowledge, values, and practices in soil nutrient management on their farms. Many of the items will be similar to items in the pre-workshop surveys, to facilitate comparison of responses across surveys. This Follow-up Survey will enable us to draw conclusions about any changes in knowledge, values, practices attributable to each farmer’s participation in either Workshop I, Workshop II, or both. We will also include items in the Follow-up survey that assess farmers’ perceptions about the value of their participation in the workshop(s), and feedback about their experiences we will use to inform our development of outreach materials to organic produce farmers in New England. We plan to conduct the Follow-up Survey through an electronic venue such as SurveyMonkey. Participants will be sent an email with a link to the survey. Non-respondents will be sent a second invitation to complete the survey. Any remaining non-respondents will be contact by phone and provided the opportunity to complete the survey over the phone.

Participation Summary

Education

Educational approach:

  1. In 2010 and 2011, research team met on-farm with farmer participants to discuss the project and address any questions. As part of the on farm research, participants received detailed soil analysis and recommendations for each of their fields sampled (65 total).

  2. In April 2011, Beth Hooker met with all farm participants from New Hampshire, to discuss previous years’ data and address questions. This was in addition to the work done with farmers by George Hamilton (UNH extension).

  3. Workshop I (April 6, 2013): see results and discussion for full analysis

  4. Workshop II (December 13, 2013): see results and discussion for full analysis

  5. Based on the on-farm research and collaborations, a set of peer-reviewed articles regarding soil fertility with biologically-based nutrient inputs will be submitted.

  6. We will also create a set of New England Regional Fact Sheets on Nutrient Management for Farms using Biologically-based Nutrient Inputs.

No milestones

Additional Project Outcomes

Project outcomes:

Impacts of Results/Outcomes

ON-FARM RESEARCH

 

We collected soils in the 2010 and 2011 growing season and have completed analytical analyses in order to complete the following activities. We are continuing to analyze the data from both years, and are in the process of writing a paper. We aim to:

  • to submit a journal article, detailing our work, within the context of other current research; main aspects of the paper will be:

o   to assess the ISNT for organic farms by surveying a wide variety of organic farms

o   to illustrate the utility of the in-season NO3-N test for determining whether soil N availability is adequate for crop production, especially in the case of the common practice of double-cropping on diversified organic farms;

o   to assess P levels across a wide number of sites with varying compost or manure addition history to determine the relationship between nutrient management practices and P levels;

o   to determine the N mineralization potential of organic soils and explore relationships between N mineralization and the ISNT, NO3-N levels over the growing season, or P levels.  

  • To create a set of New England Regional Fact Sheets on Nutrient Management for Farms using Biologically-based Nutrient Inputs

 

We are also working with the University of Maine, where they have used our samples in their research trial. This trial is in support of a new CO2 analysis that can be used to quantity soil microbial activity (Haney et al., 2008). Results from this collaboration will be analyzed to determine the applicability of this new analytical method to biologically-managed agroecosystems, with the aim to produce a peer-reviewed journal article.  

 

EDUCATION:

Though we were unable to do a statistical analysis of changes in farmer’s knowledge, values, and behaviors pertaining to soil nutrient management on their farms as a result of participation in both workshops, we were able to draw some inferences about farmer characteristics that have implications for development of outreach materials targeted to specific subgroups of farmers. First, though they had accurate didactic knowledge of nutrient management concept definitions, the less experienced farmers in the first workshop struggled with more advanced concepts and practical application of concepts. For example, they struggled in completing the mathematical calculations for a nutrient budget. Conversely, though the more advanced farmers in the second workshop demonstrated less accurate knowledge of concept definitions, most of them were comfortable and effective in applying advanced concepts to develop a detailed and adaptive nutrient budget plan. The concerns of the less experienced and more experienced farmers differed also. While the less experienced farmers in Workshop I tended to be focused on more general issues such as soil pH and long-term soil health, which could be applicable across a range of farms, the more experienced farmers in Workshop II tended to be focused on issues specific to their own settings. Members of both groups, however, identified issues of cost.  These findings may have implications for service providers in customizing their educational outreach about soil nutrient management to organic produce farmers based on farmers’ years of experience and role in farm operations.

Economic Analysis

n/a

Farmer Adoption

Farmers were generally receptive to meetings on farm, in concert with soil sampling. Some were too busy to meet, but were welcoming nonetheless. One farmer reported that he “liked having a full analysis of his soils, with helpful interpretations and recommendations”. Many farmers in MA and CT noted that they would like to have more support, but that cooperative extension was not as helpful with organic farmers. The participating farmers in NH liked working with cooperative extension, especially on these types of projects, where new approaches are being tested. Many farmers were also trying out ideas such as “nutrient dense” or “rock dust” amendments, and seemed to be unsure of which approaches would be the most useful. Most farmers reported using a combination of crop rotations, cover crops, soil amendments and fertilizers to address their sustainable soil needs; however, many were not clear on how to account for each of the components.  

For the workshop participants, please see previous entries about why we cannot make any conclusions about adoption or behavior changes based on participation in the workshops. Written comments on the surveys address challenges and questions but did not provide any formal or informal feedback. We anticipate that the Follow-up survey will be useful in collecting farmer comments.

Assessment of Project Approach and Areas of Further Study:

Areas needing additional study

Understanding the nutrient content of biologically-based nutrient inputs and predicting the amount of available N and P after repeated organic additions was highlighted as a perennial problem in this research, especially due to the lack of specific soil testing procedures created for these conditions.  In this study, we showed that the Illinois Soil N Test (ISNT) would be an excellent soil management tool for organic vegetable farmers. Based on our work, further work is needed to field test and calibrate the ISNT for integrated vegetable farms. We also showed that mid-season NO3-N testing is valuable for organic farms, which will be featured in a peer reviewed journal article.

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Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.