Organic Beans and Peas: Nutritious and Gluten-free Local Foods

Final Report for LNC11-336

Project Type: Research and Education
Funds awarded in 2011: $199,217.00
Projected End Date: 12/31/2015
Region: North Central
State: Minnesota
Project Coordinator:
Dr. Craig Sheaffer
University of Minnesota
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Project Information

Summary:

We studied production practices and analyzed markets to promote diversification of organic cropping systems with grain legumes. Our research indicates that black, pinto, and navy cultivars will be most successful for regional organic producers. Either alfalfa or corn prior to dry beans is acceptable in rotations with adequate fertility. Field beans and peas provide little N or rotation benefits to subsequent wheat crops. Field beans can be productive after a winter rye cover crop provided it is terminated in early May. Our market analysis found that there is room for more local production and sales of organic dry beans.

Introduction:

Context, Background, Rationale, and Need

Farm profitability. Crop diversification is the most powerful tool that farmers can use to reduce economic risk, disrupt pest cycles, and sustain soil quality. Soybean is the predominant grain legume in this region, but its excessive production offers little flexibility in terms of marketing. There is a critical need for more information on organic production practices for alternative grain legumes that have potential to fit our cropping systems. However, alternative crop production must go together with market development. The development of local markets would reduce risks for producers and greatly increase price stability. Currently, the market for organic edible beans is often supplied by imports from other regions, despite the fact that Minnesota and North Dakota are leading edible bean producing areas in the United States. This signals a market opportunity for locally grown organic legumes in the upper Midwest. Creating availability of organic, locally-grown edible legumes would be a welcome addition to many “locavore’s” diets and would provide environmental benefits by creating meat substitutes.

Environmental benefits. Diversification of landscapes with crops with different planting and harvest dates, cultural practices, and rooting characteristics will improve soil health and provide significant ecosystem services. Grain legumes conduct biological N fixation and can provide N for subsequent crops, thereby reducing use of synthetic N fertilizers. Alternative grain legume crops can diversify the timing of field operations in cropping systems and reduce selection for weed populations normally associated with soybean and corn production.

Quality of life issues. More financial stability through cropping system diversification will improve farm family and community vitality. Since agriculture contributes significantly to the GDP in our region, our whole society will benefit. Likewise, the local foods movement includes strong elements of community connections between farmers and consumers. Many farmers are interested in providing local foods, through direct marketing (CSAs, farmers markets, on-farm sales) and institutional outlets (Farm to School, hospitals) and retail (grocery stores, co-ops). The building of relationships supports the farm community and individual farmer’s quality of life. Another element of the local foods movement is building community food security. Legumes are extremely nutritious, affordable, and available year-round in our northern climate. There is growing interest in capacity building to include more grain staples into regional systems. One applicable example is the Appalachian Staples Food Collaborative (2008 SARE project).

Appropriateness: This research and education proposal impacts farm economics, environmental quality, and food systems. Alternative grain legumes can provide economic diversity for producers and can contribute directly to the sustainability of local food programs. The U of M Farm to School website (http://www.extension.umn.edu/food/farm-to-school/procurement/foodservice/) promotes edible beans as one of the foodstuffs tested in Minnesota Farm to School programs. There are, however, only a few farms producing organic edible dry bean or peas. Because there has been little agronomic or marketing attention given to organic legumes, we believe this project would provide important first steps in that direction for our region.

Our grant team will work with the SARE Farm to School effort (SARE project ENC08-104) to provide access to organic legumes for this program. Prior to our project, SARE had not invested in studying the organic production of grain legumes and their marketing for local foods use in our region. Our goal is to bring more agronomic and marketing resources to organic edible legumes that stimulate both the production and consumption of these legumes and increase agricultural sustainability. As a team we are intentional about creating both the production potential and the marketing outlets that are needed to create a robust organic, edible legume economy in our region.

Literature Review

Grain legume overview. Grain legumes, such as beans and peas, are gluten-free, high in fiber and protein, low in fat, and nutritionally a good complement to grain-based diets. Recent research suggests that the quality of the American diet could be improved by increasing grain legume consumption (Mitchell et al, 2009). Protein content varies among varieties and species, but is generally in the 22% or higher range (USDA, 2009). In other parts of the world, grain legumes provide the majority of protein for people’s diets. Dry edible beans contain a trypsin inhibitor and thus require heat to denature the inhibitor prior to consumption (by humans or livestock), but peas do not (Hardman et al, 1990; Oelke et al, 1991). All of these legumes can be used as feed for livestock and certain types of field peas are already commonly grown in organic agriculture in the Upper Midwest for this use.

There are several market classes for grain legumes. For dry bean, market classes consist of Black Turtle, Cranberry, Great Northern, Kidney, Navy, Pink, Pinto, Small Red, and Small White (Hardman et al, 1990). All market classes have a number of varieties with maturity classes, seed origin, vining/growth type, and some resistance/susceptible disease classification. The top four dry beans in terms of production in the U.S. are pinto, navy, black, and great northern (USDA, 2009). Dry field peas (also called split peas) used for human consumption are of the smooth, green- or yellow-seeded varieties (Oelke et al, 1991). North Dakota and Minnesota are among the top-producing state for dry beans and North Dakota is the top producer for dry edible peas (USDA, 2009).

Grain legume management in organic production. Growing edible grain legumes in organic production has special consequences for organic farmers. Organic producers are limited in terms of options for weed control, disease control, and fertilization. Also, grain legumes can be slow to establish, are poor weed competitors, can be highly susceptible to a broad range of diseases, and may require a long growing season. Unfortunately, there is a lack of research studying varieties suitable for organic production and management of organic edible legumes.  

One recent study by Singh et al (2009) in Idaho compared seven production systems, including organic, and 16 varieties and landraces of dry beans. Overall mean yields were slightly higher in conventional systems than in an organic system in this study, but several varieties performed as well in organic production systems compared to the conventional systems, suggesting that some varieties may be better suited than others to organic production. Presently, almost all variety trial information for dry bean and field pea in the Midwest is performed under conventional conditions. Research on varieties that will excel in organic systems would be a worthy and attainable objective.

Inoculants benefit dry beans and field peas by increasing nodulation and N fixation (Hardman et al, 1990; Oelke et al, 1991). However, these legumes may need supplemental N, especially if soils are low in organic matter or if nodulation is poor (Hardman et al, 1990; Oelke et al, 1991). Conventionally grown edible beans are typically fertilized with 90 kg/ha of N because of the inadequacy of the symbiosis with rhizobium. However, in organic systems this N can only realistically be applied from limited sources (e.g., manure and green manures). Responses to phosphorus and potassium additions are sometimes seen for these species when these nutrients are at low to moderate levels in the soil (Hardman et al, 1990; Oelke et al, 1991). Again, these nutrient requirements must be supplied through rotation/green manures or amendments.

Weed management is challenging for these grain legumes, as they tend to be poor competitors. Perennial weeds are especially problematic for dry beans (Hardman et al, 1990). For corn and soybean, there is evidence that some varieties are more tolerant to weeds and presumably more adapted to organic systems (Seidel and Hepperly, 2005). Differences such as these may also be found in edible legumes, leading to better recommendations for varieties in organic production.

Of the grain legumes, dry beans can be the most problematic when it comes to diseases and negative yield effects (Hardman et al, 1990). A large number of diseases are found in edible dry beans and are a yield-limiting issue in ND and MN. Disease examples include common blight, white mold, rust, halo blight, Rhizoctonia, Pseudomonas brown spot, Fusarium, Pythium, Alternaria leaf spot, and Anthracnose (Meronuck et al, 1993). Field pea can be susceptible to seed and root rots under certain circumstances (Oelke et al, 1991). As synthetic pesticides are prohibited in organic agriculture, cultural practices to control diseases in organic dry legumes will need to be determined for the Upper Midwest. Research in New York (Abawi and Ludwig, 2002) found that green manures, animal manures, and crop rotations reduced root rot severity and increased dry bean yield.

Please see References for the references in this section.

Project Objectives:

Objective 1. Determine the performance of edible bean and pea varieties. We evaluated the performance of edible bean and pea varieties. We conducted research at six sites that included on-farm locations and field research stations in Minnesota and North Dakota. We did not conduct pea variety trials to evaluate pea varieties because of the unavailability of seed of multiple organic entries. Instead we increased the number of dry bean market class trials. We did use an available pea variety in a pea rotation trial.  

Objective 2. Compare the agroecological value of edible beans and peas grown in rotation with corn, alfalfa, and wheat. A replicated 3-year rotational experiment was conducted at the Elwell Ecological Station at Lamberton, MN, Rosemount Research and Outreach Center in Rosemount, MN, the Sand Plains Research Farm in Becker, MN, and on-farm at Madison, MN. We evaluated the rotational value of peas grown alone and in mixture for barley followed by winter wheat.

Objective 3. Determine the effect of winter cover crops on yield and weed control in field beans. A replicated experiment was conducted at the Elwell Ecological Farm at Lamberton in which edible beans were grown following a winter rye cover crop. We evaluated different methods and times for termination of the winter rye cover crop. Winter rye was selected because of its ability to overwinter and regrow in the spring.

Objective 4: Develop crop enterprise budgets for organic edible beans. We used data generated from the field research objectives to develop enterprise budgets. These budgets explore the price and yield conditions under which edible beans could compete with soybean. Crop enterprise budgets organize yield, price, production, and cost information to compare profitability and help producers make decisions such as which crop to grow.

Objective 5. Identify local markets and describe the various marketing channels available to producers. Preliminary research demonstrated that there is an unmet demand for organic grain legumes. Therefore, we measured the size and scope of marketing channels for the organic dry edible bean market in Minnesota to identify the opportunities for producers. We estimated the general size of the organic edible bean market, current sources for those edible legumes, and examined a mix of channels open to producers and growers looking to market edible legumes.

Cooperators

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  • Dr. Kathy Draeger
  • Dr. Tom Michaels

Research

Materials and methods:

Objective 1. Determine the performance of edible bean varieties.

Plant Material and Seed Treatments. Twenty-eight cultivars representing 11 market classes were selected to represent dry beans commonly produced in the upper Midwest (Table 1). Just prior to planting, seed was inoculated with a commercial N-fixing Rhizobium bacteria in a peat-based suspension.

Experimental Design. To increase the impact of these results, we have included work from sites and years that were supported by funds from other grants. Yield evaluations were conducted during the 2012-2015 Minnesota growing seasons. Experimental plots were established at six locations: Southwest Research and Outreach Center in Lamberton, MN; A-Frame Farms in Madison, MN; Rosemount Research and Outreach Center in Rosemount, MN (2012-2013); NDSU Agricultural Station in Carrington, ND (2014 only); on-farm in Duluth, MN (2015 only) and the Sand Plain Research Farm in Becker, MN. No fertilizer or insecticides were applied because soil fertility was adequate for dry bean production. The Becker, MN site was irrigated as recommended for the Anoka Sand Plain.

The experimental design was a randomized complete block design with three replications, except for Carrington, ND, which consisted of four replications. The same cultivars were not grown every year, but cultivars were consistent among locations within each year. An experimental plot consisted of a single cultivar planted in a two-row plot that was 6 meters long with 76 cm row spacing. Seed count was adjusted for germination and 5% seedling mortality to obtain a target seeding rate of 172,900 plants/ha for large-seeded cultivars and 222,400 plants/ha for small and medium seeded cultivars. The seed bed was prepared by chisel plowing followed by field cultivating. Experiments were planted between May 25 and June 15. Weeds were controlled using both mechanical cultivation and hand weeding.

Data Collection and Analysis. Plots were hand harvested at harvest maturity during late September and early October to determine yields. To aid in comparisons across market classes, cultivars were grouped according to small, medium, and large seed sizes and separate analyses were performed for each seed size class. All data analyses were performed using R-software.

Objective 2. Compare the agroecological value of edible beans and peas grown in rotation with corn, alfalfa, and wheat.

Experiment 1 Dry Beans

Cropping sequence experiments were conducted at four locations in Minnesota from 2010 to 2015. To increase the impact of this research that was originally proposed only for Lamberton, MN for 2011 to 2013, we included data from years and sites that were supported by other funding. The research was conducted at four sites: the Elwell Agroecology Farm at University of Minnesota’s Southwest Research and Outreach Center in Lamberton, MN, Rosemount Research and Outreach Center in Rosemount, MN, the Sand Plains Research Farm in Becker, MN, and on-farm in Madison, MN. The three-year rotations were initiated in 2010 at Rosemount, 2011 at Lamberton, 2012 at Becker, Madison, Rosemount, and Lamberton, and 2013 at Becker and Lamberton.

The three-year crop rotation sequence consisted of the following: year 1: corn and alfalfa; year 2: dry bean and soybean; year 3: wheat. The experimental design was a randomized complete block with treatments in a split-plot arrangement. Main treatments were either corn or alfalfa in year 1, and the subplots were soybean and dry bean market classes in year 2. In year 3, all plots were cropped to spring wheat. At each site, there were four replicates of each treatment.

In year 1, organic corn and alfalfa were grown using organic practices. In year 2, a food grade soybean (‘MN1412’ or ‘MN1505SP), as well as five market classes of dry bean including black (‘Eclipse’), heirloom (‘Peregion’), kidney (‘Red Hawk’ or ‘Montcalm’), navy (‘OAC Rex’), and pinto (‘Lariat’) were grown. Legume seeds were inoculated with N-fixing rhizobia and planted in planted that had previously been corn or alfalfa. Seeding rate for each market class was as follows: 370,700 seeds/ha for soybean, 222,400 seeds/ha for small-seeded classes including black, heirloom, and navy, and 172,900 seeds/ha for large-seeded classes including kidney and pinto. The soil was field cultivated twice before planting, and rotary hoed and cultivated twice post-planting to control weeds. Broadleaf and grass weed biomass was measured at harvest. Soybean and dry bean yield was determined by hand-harvesting in the second or third week of September.

In year 3, spring wheat, either ‘RB07’ or ‘Prosper,’ was drilled at a rate of 135 kg/ha in the spring around 1 May each year, following the soybean and dry bean treatments. Wheat grain and straw yield was measured by hand harvesting each plot after reaching physiological maturity. Weed biomass from was measured at wheat harvest.

Soil samples were taken each year and analyzed for organic matter, pH, P, K and nitrate-N. In early spring of year 3, prior to planting wheat, soil samples were taken again to assess the effects of edible beans on soil nutrient status in each plot.

To test for differences in bean and wheat yield, as well as total weed biomass and soil nitrate levels, mixed effects ANOVA was performed with previous crop (corn or alfalfa) and bean type as the main effects. We analyzed experimental data using the R statistical program.

Experiment 2 Field peas

We evaluated the use of field peas harvested as grain and as a component of a pea-barley mixture on yield of a subsequent winter wheat crop in 2013-1014 and 2014-2015. This research was separated from the field bean research because of dramatically different establishment times and periods of growth. The experimental design was a randomized complete block with treatments in a split plot design. There were 4 replicates. Whole plots were two pea treatments and for comparison a barley monoculture: ‘Admiral’ field peas were grown in monoculture and harvested for grain; peas were grown in mixture with barley (‘Robust’) and harvested for forage; ‘Robust’ barley was also grown in monoculture and harvested for grain. Subplot treatments were 3 nitrogen fertilizer rates (0, 45, and 90 kg/ha) applied to the winter wheat. Planting of all treatments occurred in April of 2013 and 2014 at Lamberton, MN. Peas were seeded at a rate of 112 kg/ha and the pea-barley mixture was seeded at a rate of 67 and 108 kg/ha respectively. Peas and barley monocultures were harvested for grain in early August and the pea-barley mixture was harvested in early July when barley was at boot stage. Following tillage, winter wheat was seeded at a rate of 90 kg/ha in early September.   Nitrogen fertilizer rates were applied in September. In the year following seeding, winter wheat was harvested when mature in late July.

Objective 3. Determine the effect of winter cover crops on yield and weed control in field beans.

We established three field bean types (‘Zorro’ black bean, ‘Majesty’ kidney bean, and ‘Tiger Eye’ heirloom bean following a winter rye cover crop in 2014 at Lamberton, MN. We focused on winter rye because our preliminary experiments showed that it was the only cover crop that provided significant residue for weed control in the spring. The rye cover crop had been established in fall of 2013. The experimental design was a randomized complete block with treatments in a split plot arrangement. Whole plot treatments were four winter rye management treatments: 1) killing of the rye with tillage on 1 May; 2) chopping the rye at boot stage followed by tillage on 2 June; 3) chopping rye at anthesis followed by tillage on 10 June; and 4) rolling and crimping rye on 10 June. Within each whole plot treatment the three field bean types were planted on 20 June. Tillage operations are described in the accompanying table. We measured weed biomass at harvest of the beans and bean yield at maturity in September.

Objective 4: Develop crop enterprise budgets for organic edible beans.

Crop enterprise budgets were developed for producers to compare growing organic food grade and feed grade soybean with four market classes of dry beans including black, pinto, turtle and navy (see Organic Dry Bean Enterprise Budget attachment). We utilized cost-per-acre prices from sources in Iowa, Minnesota and North Dakota. We formatted cells with formulas to calculate revenue per acre and costs per acre to get the net returns per acre. Revenue is calculated from yields and estimated market prices. Costs include the costs for seed, fertilizer, machinery operations, labor, management, rent and insurance. We designed three spreadsheets. The first, ‘Research Results’, utilized values from our crop rotation experiment.   The second, ‘Hypothetical’, uses values that a typical organic producer might use. For this option, we modeled the values based on the production practices of the organic farmer on whose farm we conducted research. The final spreadsheet, ‘Blank’, has formulas, but values have not been entered, for producers to use their own numbers based on their specific production practices.

Objective 5. Identifying local markets and marketing channels

Dry Bean Producer Survey. Research was conducted from September 2012 - March 2013 to examine the experiences of edible dry bean producers. Producers contacted for this research were those who are listed on the U of M Farm to School website. Wholesale bean producers listed on the state’s local food directory website, Minnesota Grown, were also contacted and asked to participate in this research project. The U of M Farm to School Toolkit included 20 self-identified growers of edible dry beans who were available to provide beans for farm-to-school programs. We did not receive responses from six growers and three growers had never grown edible dry beans or not grown them recently. The remaining 11 growers were asked whether they were growing dry beans, whether they grow organically, and whether they had been contacted by schools regarding dry beans.

Farmers Market Vendor Survey. A study of Minnesotan Farmers’ Market vendors began in January 2014 to further understand the potential demand for edible dry beans at these markets. The Operations Manager for the Minnesota Farmers’ Market Association, Kathy Zeman, emailed 606 vendors a link to the survey, of which 66 participated in the survey, for a response rate of 10.8%. The survey included both quantifiable and free responses to elicit a full perspective of vendors’ experiences selling dried beans. Of the vendors who participated, 18 reported that they were currently growing and selling dry beans. Those not growing dry beans were directed to separate questions to complete the survey.

Dried Bean Distributor Survey. Bean distributors in Minnesota were interviewed to examine market channels for edible dry beans. Responses from bean distributors were intended to help improve understanding of the role that distributors play in the dry edible bean market. A total of 16 bean distributors were identified and contacted for information. Two of these distributors were no longer selling dry beans. The remaining distributors were called and given the opportunity to set up a phone interview or complete an emailed survey. Six respondents completed phone interviews, two completed in-person interviews, and one completed an emailed survey, resulting in a 64.3% response rate.

Dry Bean CSA Report. CSA farmers were surveyed in Minnesota to improve understanding of direct-to-consumer market channels.  The survey was distributed to 121 CSA farmers via email in May 2013. Of the farmers contacted, 37 completed the survey, for a response rate of 30.6%.  The survey included questions about general business operations, current and past production of dry edible beans, incorporation of dry beans into CSA shares, and perceived barriers to producing and marketing dry beans. The questions were distributed in the form of an email survey to make it easier for farmers to respond. Respondents were given the ability to write in responses for some open-ended questions, such as those about perceived barriers to production and marketing of dry beans.

Co-op Grocery Store Survey. Co-op grocery store personnel were surveyed to help improve understanding of retail market channels. The survey was distributed to 21 co-op managers and bulk buyers representing a total of 24 co-ops in Minnesota and North Dakota. These co-ops were identified using the National Cooperative Growers Association list of co-ops. A total of 11 responses were received (52.4% response rate). One of the respondents was the bulk buyer for a co-op with three locations, so a total of 13 stores were represented. All respondents were located in Minnesota. Respondents were initially contacted via telephone and given the option of scheduling a telephone interview or completing an emailed version of the survey. In total, seven respondents completed emailed surveys, four completed phone interviews, and one completed part of a phone interview and then emailed more information.  

Restaurant Survey. Restaurant managers in the Twin Cities and in Greater Minnesota who actively procure and advertise the use of locally grown products were surveyed on usage and potential future usage of locally grown edible dry beans. The responses from restaurant managers were intended to help improve understanding of direct-to-consumer market channels. The survey was distributed to 74 restaurants in the Twin Cities and Greater Minnesota via email in August 2013, with follow-up e-mails throughout September. Of these restaurants, 29 completed the survey, giving the study a response rate of 39%. The survey included questions about use, qualities desired, amount purchased and varieties used of edible dry beans. Surveys were distributed by e-mail for ease of response. The survey gave respondents the ability to write in responses to the more open-ended questions, such as questions about experience purchasing edible dry beans and reasons for not purchasing locally grown edible dry beans in the past.  

Research results and discussion:

Objective 1. Determine the performance of edible bean and pea varieties.

Yield across all seed classes and cultivars ranged from 1181 kg/ha (‘OAC Lyrik’) to 2839 kg/ha (‘Maverick’). Medium seeded (mean = 2408 kg/ha) cultivars outperformed small (mean = 2202 kg/ha) and large (mean = 1546 kg/ha) seeded cultivars (Table 2). Black and pinto were consistently high-yielding market classes within the small and medium seed classes, and pink and small red were the highest yielding market classes within the medium seed class. No observable trend in yield was observed among cultivars in the large seed class.

Examination of 95% confidence intervals associated with the best linear unbiased estimate of yield suggested true differences among cultivars within each seed class (Figure 1). Highest yielding cultivars within the small, medium, and large seed classes were ‘Zenith’ (mean = 2621 kg/ha), ‘Maverick’ (mean = 2840 kg/ha), and ‘OAC Inferno’ (mean = 2385 kg/ha), respectively. Lowest yielding cultivars within the small, medium, and large seed classes were ‘Lightning’ (mean = 1749 kg/ha), ‘Matterhorn ‘(mean = 1966 kg/ha), and ‘OAC Lyrik’ (mean = 1181 kg/ha), respectively. In no instance did a cultivar achieve the target plant population. In all three classes, the lowest yielding cultivar was also associated with the lowest plant population (Table 2). In 2015, the variety trial was repeated at three of the previous sites (Lamberton, Madison, and Carrington), plus an additional new on-farm site in Duluth. These results have not been fully statistically analyzed, but preliminary results are shown in Table 3.

Favorable and unfavorable environments differed between the seed size classes. Seven favorable environments and five unfavorable environments were identified in the small seeded class; five favorable and seven unfavorable environments were identified in the medium and large seeded classes. Yield of each cultivar within a seed class was subject to stability biplot analysis by plotting yield in favorable environments on the x-axis and yield in unfavorable environments on the y-axis (Figure 2). Cultivars that performed well in both favorable and unfavorable environments have dynamic stability, an indicator of good yield performance despite environment. These were plotted in the upper-right quadrant of the graph. Cultivars of the small-seeded class with dynamic stability included ‘Super Jet’, Jaguar’, ‘Zenith’, and ‘Alpena’. Cultivars of the medium-seeded class with dynamic stability included ‘Lariat’ ‘Maverick’, and ‘Rosetta’. Cultivars of the large-seeded class with dynamic stability included ‘Red Hawk’, ‘Majesty’ and ‘OAC Inferno’.

Growers new to Minnesota dry bean production and/or organic management should first consider reliable, stable market classes such as pinto, pink, and black. In doing so, growers can be better prepared to obtain stable yield and a reliable economic return. Cultivars representative of the small/medium seed classes, such as ‘Maverick’, ‘Rosetta’, and ‘Zenith’, exhibited adequate dynamic stability and were less influenced by effects of environment. Because large seeded market classes were subject to larger environmental effects and provided less economic return, the production of large seeded cultivars, such as ‘OAC Inferno’ or ‘Majesty’, may be best suited for organic producers with well-established management strategies or previous dry bean production experience. It is of the utmost importance, however, that growers evaluate their system, soil, and experience in conjunction with cultivar recommendations.

Objective 2. Compare the agroecological value of edible beans and peas grown in rotation with corn, alfalfa, and wheat.

Experiment 1 Dry Beans

Bean yield. Averaged across all 8 site-years, there was no significant rotation effect on bean yield, showing that the previous crops of either corn or alfalfa gave similar yields over a long-term period with a range of weather conditions. Overall, bean yields were highest in 2011 with 2,655 kg/ha, followed by 2012 and 2013 with an average of 1,852 kg/ha, and lowest in 2014 with 1,234 kg/ha. Reductions in dry bean yields may be attributed to early-season soil water and weed growth. Bean yields differed by type with soybean yielding the highest on average, followed by pinto, black, navy, heirloom, and kidney beans (Table 4).

Wheat yield. Overall, wheat yields were highest in 2013 and 2015 at 3,100 and 3,096 kg/ha, respectively, followed by 2,521 kg/ha in 2012 and 1,920 kg/ha in 2014. The high wheat yields appear to have no correlation to bean yields, as evidenced by the low bean yields in 2014 followed by relatively high wheat yields in 2015. Wheat yields were up to 1,700 kg/ha greater at Lamberton as compared to the other locations, with Madison wheat yielding the lowest (Table 5). These differences do not correspond with bean yield response, as bean yields were lowest at Lamberton. This difference in yield response could be, in large part, due to the difference in precipitation. Bean type had no discernable effect on wheat yields when compared across environments. This suggests that environment was a strong driver of wheat yield response.

Weed biomass. Weed biomass in the bean phase varied significantly by year, location, and bean type. Previous crops of corn or alfalfa had similar effects on weed biomass. Total weed biomass was at least two times higher in 2014 than the other years, likely due to greater precipitation. Lamberton had significantly more weeds during this phase than the other locations, with an average of 4,567 kg/ha total weed biomass, compared to the 2,869, 1,555, and 1,368 kg/ha weeds at Rosemount, Becker, and Madison, respectively. Bean type also influenced total weed biomass; navy bean plots had the most total weed biomass on average with 3,491 kg/ha, and soybean plots had the least weeds with 2,324 kg/ha. Total weed biomass in the wheat phase also demonstrated more weeds in 2014 than other years. The plots that had been previously planted to alfalfa had greater weed biomass with 4,350 kg/ha, as opposed to corn plots with 3,192 kg/ha total weed biomass. Bean type from the previous year had no bearing on total weed biomass in the wheat phase.

Based on our results, we recommend that either alfalfa or corn prior to dry beans is acceptable in rotations if there is adequate existing soil fertility. However, in cases where there is not adequate soil nitrogen, we would expect that alfalfa prior to dry beans would increase yields, given the higher bean yields seen here following alfalfa at three out of the four locations.

Experiment 2 Field Peas

Peas and pea-barley mixtures were grown in rotation with winter wheat. In the first phase of the rotation, pea monoculture yields averaged about 1602 kg/ha while barley yields averaged 4063 kg/ha (Table 6). In the second phase of the rotation, when we compared unfertilized wheat yields (0 kg/ha N applied), we found no difference in wheat yields for the peas harvested for grain, barley harvested for grain, and a pea-barley forage mixture, indicating that peas did not contribute significant amounts of N or rotation effects to the following winter wheat crop (Table 7). However for the pea monocultures and the pea-barley mixture, N fertilization did not increase yields compared to the no N (0 kg/ha N applied). Nitrogen fertilization did increase wheat yields following the barley monoculture. Producers should not depend on peas to contribute a significant amount of N for subsequent winter wheat grown likely because of removal of N in the grain.

Objective 3. Determine the effect of winter cover crops on yield and weed control in field beans.

For all dry beans, yields were greatest when the beans were killed by tillage on 1 May. Delaying killing followed by tillage on 20 May resulted in lower yields (Table 8).   Lowest bean yields and greatest weed yields occurred when the winter rye was rolled and crimped. Chopping the winter rye at anthesis and tilling resulted in greater black and kidney bean yields than rolling the winter rye.   The relative yield ranking of the three field beans was similar for all winter rye management treatments. Yields were highest for black bean, and lowest for ‘Tiger Eye’ with ‘Majesty’ kidney bean yields being intermediate.   We conclude that for a winter rye cover crop system, early tillage is beneficial to field bean yields likely because of soil moisture depletion when winter rye is allowed to reach anthesis and because of significant weed growth associated with rolling winter rye. Allowing rye to reach anthesis was not beneficial to bean yields compared to earlier chopping and tillage.

Objective 4: Develop crop enterprise budgets for organic edible beans.

Net Returns (Research Results). We calculated returns using the yields and production techniques in the rotation experiment (Objective 2). The production costs for dry bean are very similar to soybean, but dry beans have additional costs for fertilizing, weed control and sometimes harvesting. The returns for all types of dry beans (black, navy, kidney and pinto) were higher than for food grade soybean.   Food grade soybean had a net return of $428/acre and the net return of the dry beans ranged from $974 – 1150 per acre. However, it should be noted that these kinds of experiments may not be representative of real world conditions. For instance, it is usually recommended that dry beans receive 40-50 lbs of nitrogen per acre, but fertilizer was not applied per the research protocol.

Net Returns (Hypothetical). In our second example, we estimated what the net returns might be at the field scale using figures from the organic producer’s farm where we conducted the research. We found the same trend continued with all dry bean market classes providing a higher net return as compared to feed grade and food grade soybean. Unlike with soybean, producers growing dry bean should have buyers for their crop pre-arranged.

While our research and hypothetical results show potentially a larger profit for organic dry bean market classes as compared to soybean, we recommend that growers use these budgets only as a starting point in their what-to-grow decisions. Because production challenges can greatly affect profit, we recommend that new growers experiment with only limited acreages of dry beans.

Please see attached file (Organic Dry Bean Enterprise Budget) for interactive version that farmers can use to calculate their own returns.

Objective 5. We will identify local markets and describe the various marketing channels available to producers.

Dried Bean Producer Survey. Results indicate that very few growers in the U of M Farm to School Toolkit have experience selling local dry beans to Minnesota schools. Of the 11 interviewed, only one had experience selling dry beans to local school districts. When this grower was asked whether or not they were contacted via the U of M Farm to School Toolkit, the grower stated that her relationship with the local school district was a result of personal initiative and not the result of the school coming to her. While the base of dry bean growers could not be expanded, nor the relative success of the U of M toolkit versus the Minnesota Grown directory compared, a result of this investigation has been the addition of a specific category to differentiate and promote local wholesale dry bean growers separate from fresh beans in the Minnesota Grown directory.

Farmers Market Vendor Survey. Results of the survey show that Minnesota growers have a range of experience in producing dry beans, with 30% cultivating these beans for more than six years to 10% of respondents currently in their first growing season. Size of operation also varied from small growers with less than one acre to larger operations planting over 40 acres of dry beans. Only 7.6% of survey participants currently sell their dry beans at the farmers market. The varieties of dry beans grown in 2013 are illustrated in Figure 3. Black beans were the most cultivated variety with 50% of surveyed farmers planting black beans, followed by kidney, pinto, and Lima varieties. Six farmers indicated they grew heirloom varieties, and, of these, the ‘Peregion’ variety was most grown. Two farmers mentioned that their black bean varieties were the best-selling variety at farmers markets.

While some vendors have made profit from selling edible dry beans at farmers markets, they related the difficulty in growing these beans. Farmers report dry beans as labor intensive and lacking a high return compared to other crops. One farmer commented that Minnesota’s wet fall weather can cause pods to mold easily, decreasing crop yield. However, a different grower with two years of experience, increased their dry bean production by four times the previous year.

The experience edible dry bean growers have selling their product at farmers markets varies in many respects. These include what bean varieties they supply and how they are market these products to consumers. Specialty heirloom varieties are not as widely available as other varieties and can be sold for more than non-heirlooms varieties. Certain heirloom varieties, like Jacob’s Cattle, feature unique colorings that are attractive to consumers. Successful sale of dry beans can also depend on marketing and merchandising methods used by vendors. This research indicates growers have varying success in selling beans at farmers markets. One barrier may be that farmers markets are not recognized by consumers as a source of dry beans. Demand for dry beans may increase if more consumers see farmers markets as a place they can purchase locally grown dry beans.

Dry Bean Distributor Survey. Most distributors deal with limited varieties of beans. Four respondents distributed only one variety of dry bean, four distributed three varieties, and one distributed six varieties. One respondent said that, in addition to the three varieties of beans that they distribute, they will handle other varieties of beans on a consignment and custom basis. Figure 4 shows the varieties of beans sold by distributors. The most distributed beans in Minnesota were Navy, Kidney, and Pinto varieties, but the nine respondents surveyed sell a total of eight varieties of beans. Distributors sold between 10 million pounds and 300 million pounds of dry beans each year. The median number of beans produced was 20-28 million pounds. Most distributors were reluctant to give a dollar estimate of their 2012 dry bean sales, but estimates ranged from $5-$15 million.

All distributors reported purchasing products from growers using contracts or on the open market. Distributors provide aggregation, sorting, cleaning, packaging, and marketing of the product. One distributor is willing to process beans for growers and then allow those growers to market their own product. This is typically done for specialty varieties. All distributors sell all or most of their beans to processors. Eight out of nine distributors said the processors they sell to are canners. Another distributor said that in addition to selling beans to canners, they sold some to dry processors. Most distributors said that there is generally more money in canning. No distributors reported selling beans directly to retailers. Generally, retailers buy their beans from processors.

Dry Bean CSA Report. While a substantial number of CSA farmers had considered growing beans for their CSA shares, fewer than half of them actually did so. A slim majority of farmers have grown dry beans at some point, but this was primarily for personal consumption. There are numerous barriers to producing dry beans on a CSA farm (Figure 5). Beans are labor-intensive and require a large amount of land relative to their market value. Equipment can be purchased to make the bean processing more practical. However, this equipment is too costly for CSA farms that only have a small acreage devoted to beans. In addition, while beans are costly to produce, they have a relatively low market value. Local organic producers would have to be able to convince customers to pay a premium for their product, but this could prove difficult since it is difficult to differentiate locally grown, organic dried beans from conventional grown ones (Figure 6). CSA farmers would benefit from reducing the cost of processing beans. This could involve sharing their equipment, bringing beans to a centralized processor, or purchasing beans from a larger local producer to add to their shares.   More research looking into the feasibility these options would be beneficial. CSA farmers would also benefit from a program that helps them market local organic beans to consumers.

Co-op Grocery Store Survey. Based on this survey, it appears there is room for small producers to enter into the dry bean market by selling through co-ops. A majority of respondents said that they would be open to sourcing beans from local producers, but only if there was a consistent supply. Farmers would need to be able to provide co-ops with a sufficient volume of beans to meet demand. In addition, small producers may struggle to produce product that is price-competitive. Some co-ops are willing to reduce their mark-up for local products in an effort to make them more competitive, but it is questionable whether this could completely compensate the cost to produce and transport these beans. Co-ops generally reported that customers may be willing to pay a premium for local product. However, the premiums customers are willing to pay for staple products, such as beans, are low.  

Respondents seemed interested in sourcing any variety of beans through local producers. However, there seems to be greater unmet demand for specialty varieties. The most common locally sourced beans were varieties such as black turtle and kidney beans. Seven respondents felt that there would be a demand for locally sourced heirloom beans, but only one co-op offered an heirloom blend. Focusing on meeting unmet demand for specialty varieties of beans could help farmers be more price competitive.   Small producers may have trouble producing common varieties of beans at competitive prices because consumers are not willing to pay a large premium for staple products. These farmers may find it easier to market specialty beans. Higher-priced specialty crops also sell in lower volumes.   This could help small producers who are unsure of how much they can produce meet the co-ops’ demands to provide sufficient volume of product.

Restaurant Survey. Many restaurant managers in Minnesota who are focused on utilizing local ingredients incorporate dry beans into their menu items (Figure 7), but fewer of these source their dry beans from local growers. Roughly half of the managers surveyed used dry beans in their dishes every day, but only 10 out of 26 (38%) used locally grown dry beans. Some managers stated they were unable to use locally grown dry beans because they couldn’t source them from their supplier and weren’t available. Factors that would make them more likely to purchase local beans were obtaining a consistent supply, purchasing these beans for a good price, and being able to select from different varieties of dry beans. Those restaurants who already bought dry beans from local growers stated a variety of reasons for doing so. The top three reasons were to support growers, that they wanted dry beans for their restaurant, and to add variety to the restaurant menu. Consistent supply was noted as a top factor for restaurants when considering increasing their purchasing of locally grown dry beans, followed by having a good price point, and being able to choose from a number of dry bean varieties (Figure 8).

For full marketing report, please see A Survey of Dry Bean Supply Chains in Minnesota (1).

Research conclusions:

One of the most important outcomes of this project has been the formation of a team of researchers, educators, producers, and others devoted to increasing the production and consumption of locally-grown organic edible beans. Our team has participated in a great number of outreach events related to dry beans where we have made contact with producers who are interested in dry beans. Consequently, we have been able to provide production and market information to our targeted audience.

From a research standpoint, the variety trial work from this SARE project has led to other funded projects on breeding that will result in new varieties of market class and heirloom dry beans adapted to organic systems. Our team will continue to facilitate communication among producers, university staff, and government agencies about dry edible beans.

One result of market survey has been the addition of a specific category to differentiate and promote local wholesale dry bean growers separate from fresh beans in the Minnesota Grown directory. Prior to this project, growers were listed as having grown generic “beans”, which did not help schools or consumers differentiate growers who were growing dry beans rather than green beans.

The results of the market analysis indicate there is room for more local production and sales of edible dried beans. The attached market analysis document contains specific recommendations to producers for buyers that include farmers markets, distributors, CSAs, co-ops and restaurants. These will help in future work to develop concrete markets for organic dry beans.

The groundwork for the future is in place for creating markets for organic edible beans. We believe that demand for and preferential buying of locally grown organic edible legumes will increase. As a result, there will be increased diversification of Midwest landscapes because organic producers will be encouraged to add a variety of edible legumes to grain cropping systems. Options for local markets for organic producers will be created. Increased quantities of locally grown, protein-rich legume grains will be available to rural and urban populations through various marketing channels that includes retail stores (like whole foods co-ops), community supported agriculture (CSA) shares, and institutionally through programs like Farm to School. By facilitating local production and use, we will reduce the distance (and energy used) in the food production system. Because the ecoregions of MN and ND are diverse, our results will apply to a broad audience including local producers and producers throughout the Midwest.

Economic Analysis

Objective 1. In the organic edible bean variety experiment, gross revenue per acre was highly associated with yield (Table 9). Maximum gross revenue was associated with the pink market class ($2378/acre), while minimum gross revenue was obtained from the dark red kidney market class ($1402/acre). It should be noted that the pink and small red market classes consisted of only one cultivar; reservation must be taken in evaluation of these revenue estimates. According to price estimates, kidney seed types received $0.10-$0.25 premium/cwt over black, navy, pinto, small red, and pink market classes. Despite this price differential, yield disparities still made small seeded market classes more profitable than all kidney types. The one deviation from this trend was the light red kidney, which was slightly more profitable than the navy market class. Further, the lack of available organic seed and ill-defined market prices make it difficult to compile a comprehensive enterprise budget; details regarding production inputs would contribute to a complete economic analysis.

Objective 2. Using data from the dry bean rotation experiment, we examined the economics of production. This is hard to estimate due to widely fluctuating bean prices and varying production costs, resulting in profits that are highly variable. Additionally, organic bean seed is often unavailable, especially in large quantities. Nevertheless, many large-scale bean producers are considering organic production given the price advantage (~150%) for the organic crop (Heilig, 2010). Our analysis comparing different dry bean types following either corn or alfalfa integrates both direct and indirect costs (Table 10). Production costs include seed, weed management, fuel, labor, harvest, and other machinery costs. Gross income from each crop was estimated based on crop yield and current market prices; market prices were gathered from regional grain buyers, and organic seed cost was estimated across classes at $0.60 lb. With the exception of kidney bean, dry beans tended to have lower returns as compared to soybean. However, as demand for local organic dry beans grows, premiums for organic dry beans may increase, which could help narrow the gap.

Objective 4. See Results Section of Objective 4 for information on crop enterprise budgets. Please note that the crop budget calculations vary from the economic analyses for Objective 1 and 2 as listed above.

Objective 5. See Results Section of Objective 5 for information on survey results that pertain to economics.

Farmer Adoption

An estimated 900 farmers and agricultural professionals have been reached through our outreach events and we anticipate several hundred more per year once our website on dry beans is completed later this year. Specific recommendations we would make to farmers as a result of this project include the following:

Minnesotan organic farmers new to dry bean production should first consider reliable, stable market classes such as pinto, pink, and black to obtain stable yield and a reliable economic return. Cultivars representative of the small/medium seed classes, such as ‘Maverick’, ‘Rosetta’, and ‘Zenith’, exhibited adequate dynamic stability and were less influenced by effects of environment. Because large seeded market classes were subject to larger environmental effects and provided less economic return, the production of large seeded cultivars, such as ‘OAC Inferno’ or ‘Majesty’, may be best suited for organic producers with well-established management strategies or previous dry bean production experience.

Based on our rotation experiment, we recommend that either alfalfa or corn prior to dry beans is acceptable in rotations if there is adequate existing soil fertility. However, in cases where there is not adequate nitrogen, we would expect that alfalfa prior to dry beans would increase yields, given the higher bean yields seen here following alfalfa at three out of the four locations.

Field beans can be productive after a winter rye cover crop provided it is terminated in early May. However, organic producers should be aware that our research found that the lowest bean yields and greatest weed yields occurred when the winter rye was rolled and crimped.

While our crop budgets showed research and hypothetical results with potentially larger profits for organic dry bean market classes as compared to soybean, we recommend that growers use these budgets only as a starting point in their what-to-grow decisions. Because production challenges can greatly affect profit, we recommend that new growers experiment with only limited acreages of dry beans.

The market analysis suggests that small growers such as CSA or farmers market operations should grow heirloom dry beans rather than market class dry beans to differentiate their product. While yields of heirlooms are lower, specialty products such as these can command a higher price from consumers.

Participation Summary

Educational & Outreach Activities

Participation Summary:

Education/outreach description:

Journal Publications

Swegarden, H. R., C. C. Sheaffer and T. E. Michaels. Yield Evaluation of Commercial Dry Bean Market Classes (Phaseolus vulgaris L.). Manuscript in progress

Flavin, C. T. Michaels, N. Ehlke, J. Lamb, and C. Sheaffer. Rotation Effects of Edible Dry Beans and Soybeans in Organically Managed Systems. Manuscript in progress.

Theses

MS Thesis completed: Swegarden, H. R. 2015.   Selection of commercial and heirloom common bean (Phaseolus vulgaris L.) for organic production in Minnesota. University of Minnesota.

MS Thesis in progress: Flavin, C. Spring 2016. University of Minnesota.

Other publications

Our field research will help us collaboratively develop recommendations that show benefits of organic edible legumes in cropping systems, including economic return, legume N contribution, and weed management. The information gathered from this project will be incorporated into online publications and published on a University of Minnesota website focused on all of our projects involving dry edible bean. Our overall plan is to release this information from this project, combined with our other dry bean research on breeding (market class and heirloom dry beans), in an accessible format to provide grower recommendations for organic dry bean production in the Upper Midwest. The market analysis and crop enterprise budgets (both included as attachments to this report) will also be made available on this website.

Outreach events

  • University of Minnesota Organic Field Day, July 9, 2013: The Basics – Soil, Fertility, Weeds, and Crop Rotations at Southwest Research and Outreach Center in Lamberton, MN. Drs. Craig Sheaffer and Tom Michaels discussed organic bean research with attendees while touring plots.
  • Research assistants Claire Flavin and Hannah Swegarden presented bean research to a group of 30 agritourists from Fargo, ND at the Jorgenson farm in Big Stone County, MN on September 28, 2013.
  • Presented webinar titled “Organic Dry Bean Production Systems and Cultivar Choices” through eOrganic’s webinar series on November 12, 2013.
  • The Minnesota Organic Conference on January 10, 2014 in St. Cloud, MN.       Dr. Tom Michaels, Dr. Craig Sheaffer, Hannah Swegarden (grad student), and Claire Flavin (grad student) presented on the dry bean weed control and rotation projects. 36 people were in attendance.
  • 2014 Minnesota Organic Conference on January 10, 2014 in St. Cloud, MN. You Can Grow Beans and Market Them Locally. We presented results and ongoing research of organic edible dry bean supply chain research. Approximately 35 people in audience.
  • Midwest Organic and Sustainable Education Service Organic Conference in LaCrosse, Wisconsin on March 1, 2014. Dr. Tom Michaels, Dr. Craig Sheaffer, Hannah Swegarden (grad student), and Claire Flavin (grad student) presented on the dry bean weed control and rotation projects.
  • 2014 Midwest Organic and Sustainable Education Service Conference in LaCrosse, WI on March 1, 2014 You Can Grow Beans and Market Them Locally. We presented results and ongoing research of organic edible dry bean supply chain research. Approximately 75 people in audience.
  • The Organic Field Day at the Lamberton Southwest Research and Outreach Center held on July 11, 2014. This organic field day is the largest in the state with about 100 participants. In 2014, the field tour featured the research plots from the dry bean field research.
  • The NDSU Carrington Research Extension Center Annual Field Day on July 14, 2014. Graduate students Hannah Swegarden and Claire Flavin shared organic dry bean research results and gave research plot tours.
  • Graduate students Claire Flavin and Hannah Swegarden presented research posters on organic edible beans during the Production Ag Symposium at the University of Minnesota, and presented a seminar to the What’s Up in Sustainable Agriculture series at the University of Minnesota.
  • On-farm field day featuring organic dry beans held on September 19, 2014 in Madison, MN. Attendees toured on-farm plots from two of this project’s experiments.
  • Midwest Organic and Sustainable Education Service Organic Conference in LaCrosse, Wisconsin on February 27, 2015. Hannah Swegarden (graduate student) presented a poster on the dry bean project. This conference attracts thousands of attendees from across the country every year.
  • The Organic Field Day at the Lamberton Southwest Research and Outreach Center held on July 15, 2015. This organic field day is the largest in the state with about 100 participants. In 2015, the field tour featured the research plots from the breeding dry beans and soybean projects.      
  • Albert Lea Seed House open house in November 2015 in Albert Lea, MN. Claire Flavin discussed her work on rotation and weed control in dry beans.
  • ASA-CSSA-SSSA Annual Meeting in Minneapolis, MN on November 18, 2015.       Claire Flavin presented her results from the rotation experiment at this conference.
  • The Minnesota Organic Conference in St. Cloud, MN on January 9, 2016. Carmen Fernholz (A-Frame Farms), an organic producer who participated in our on-farm dry bean research, was part of a panel with other organic dry bean growers on pest management in organic dry beans.

Engaged students from the College of Design’s Surface Design Class, Applied Economics, and Environmental Sciences. In 2013 we reached out to the College of Design’s surface design class to have 25 undergraduate students design images for bulk bags used to store and sell organic, locally grown dry beans. Professor James Boyd Brent incorporated this project into the student’s coursework and each student developed a concept, design, and final product. During the semester the project research team met with the students multiple time to discuss the project and view the resulting designs which were silk screened onto the bean bags. Haberer Foods International of Morris, MN, the major organic bean processor in the region, provided the 50# bags. The resulting class product was a collection of 19 unique artistic 50 pound bulk bean bags (Figure 9). These bags have been displayed prominently on campus bringing further attention to the University’s work developing organic edible dry beans.

In addition to the classroom contact, the project worked with a graduate student in Applied Economics (and associated with the Center for Urban and Regional Affairs) to collaborate on the supply chain research. Another undergraduate was engaged to interview bean processors in the state.  

Project Outcomes

Recommendations:

Areas needing additional study

Objective 1: The market class variety trial work has demonstrated the need for improvement of current dry bean varieties to improve adaptation to organic systems. Currently, dry beans are much less competitive when compared to soybeans.

Objective 2: The rotation work indicates that more long term studies on rotations need to be carried out to build upon the knowledge of rotation effects, including a more in-depth analysis of nitrogen dynamics, and ecological benefits in dry bean systems.

Objective 3: Other cover crop species could be examined to see what effects they have on dry edible beans.

Objective 4: Weed management and harvesting complications for dry beans need to be addressed for producers to gain better yields and obtain good net returns.

Objective 5: The market survey results suggests that research is needed to provide solutions for producers to overcome major challenges of dry bean production, such as high equipment costs, low market value, and difficulty differentiating organically grown dried beans from conventional. More research is needed to identify other potential distributors of organic specialty beans. In addition, research into how farmers can process beans at low volumes in a cost effective way would benefit producers who are unable to produce semi-load quantities. CSA farmers would benefit from reducing the cost of processing beans. This could involve sharing their equipment, bringing beans to a centralized processor, or purchasing beans from a larger local producer to add to their shares. More research looking into the feasibility these options would be beneficial. CSA farmers would also benefit from a program that helps them market local organic beans to consumers. Further work is need to address major challenges that include high equipment costs, low market value, and difficulty differentiating organically grown dried beans from conventional. Consistency of supply, adequate volume, purchasing price, and locating sources for local dried beans are issues for both co-ops and restaurants.

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.