Potential Economic and Nitrogen Benefits of Fababean as a Double Purpose Cash and Cover Crop in Northern California

Progress report for SW19-902

Project Type: Research and Education
Funds awarded in 2019: $348,772.00
Projected End Date: 09/30/2022
Grant Recipient: California State University- Chico
Region: Western
State: California
Principal Investigator:
Dr. Hossein Zakeri
California State University- Chico
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Project Information


The benefits of cover crops to soil health and environment is well understood. However, socio-economic limitations such as the costs of cover cropping and lack of general knowledge about its long-term benefits limit this sustainable farming practice. Especially in California where suitable weather allows year around cash crop production, cover cropping does not seem profitable for most growers. We have formed a team of agronomists and extension specialists, agriculture business and business information specialists, a food and nutrition specialist, a breeder, and three growers to identify short-term economic benefits of fababean cover crop that can promote its cultivation in intensive cropping systems of California. Specifically, we will quantify total fresh pod production of fababean cover crop and its potential values, plus the value of added nitrogen to soil from the fababean nitrogen fixation.   

The research consist of two field trials at Chico and Lockeford, CA, and demonstration fields at three growers’ fields. In a split-plot trial in Chico, we will quantify 1) fababean fresh pod production from multiple harvests, and 2) potential economic benefits market values of the pods, and 3) nitrogen fixation and nitrogen benefits (added nitrogen to soil) of fababean in response to multiple pod removals. The results of this 3-years trial will determine the economic potentials of fababean as dual-purpose cash & cover crop. In the second field trial at the NRCS Lockeford Plant Material Centre, we will investigate the effects of termination time on nitrogen fixation and nitrogen benefits of the fababean cover crop. At three growers’ fields, we will estimate fresh pod production and potential economic values of pods in the large scale.

The experiments and the demonstration fields will be presented to growers and Chico community. We will perform at least one field day and present the trials to local growers at each location (Chico and Lockeford) every year. In addition, we will 1) prepare and present foods from fababean pods and immature seeds to the Chico community, 2) obtain consumers’ opinions in the form of survey, 3) publish the results in North State Agricultural Bulletin,  4) present the results in professional meetings, and 5) aim to publish at least one peer-reviewed paper in a high-ranked crop science journal.  

It is anticipated to educates local farmers and encourage them to include fababean in their rotations. It is also expected to educates the Chico community about the potentials of fababean as a healthy food and increase its consumption in California. Considering the diversity of activities, the project will create substantial learning opportunities for undergraduate students at CSU, Chico to learn from different aspects of the research. The students will be involved in planting and field trials, sampling and data collection, food demonstrations and food surveys, presenting the results at local and national conferences. Contingent on the results, we will seek further funding opportunities to identify national and international markets for the fababean fresh pods.

Project Objectives:
  1. Quantifying fresh pod production potentials of fababean cover crop
  2. Quantifying N fixation and N benefits (added N to soil) of fababean in response to pod removal and termination time
  3. Quantify N fixation and N benefits of fababean in ricelands, orchards, and annual cropping systems of northern California;
  4. Quantifying the amounts of removed N in harvested biomass, fresh pods, and grain of fababean cover crop.
  5. Educating California growers about the economic benefits of the fababean cover crop.
  6. Presenting foods made of fababean fresh pods to the public to promote the consumption of fababean as a healthy diet.


Click linked name(s) to expand
  • Dr. Kyle Brasier (Educator and Researcher)
  • Mrs. Sandy Fisher - Technical Advisor - Producer
  • Mr. Rory Crowley - Technical Advisor - Producer
  • Jessica Lundberg - Technical Advisor - Producer
  • Dr. Junda Jiang (Researcher)
  • Dr. Whitney Brim-DeForest - Technical Advisor (Educator and Researcher)
  • Dr. Maria Giovanni - Technical Advisor (Educator)
  • Dr. Eric Houk - Technical Advisor (Researcher)
  • Dr. Jinguo Hu (Researcher)
  • Dr. Arash Negahban (Researcher)
  • Dr. Margaret Smither-Kopperl (Researcher)



1- Fresh pods of fababean cover crop can produce additional income for growers 

2- Harvesting fababean fresh pods reduces nitrogen benefits of fababean cover crop  


Materials and methods:

Potentials of faba bean as dual-purpose food and cover crop:


  • Two faba bean varieties (Windsor & Sweet Lorane) were grown in Chico for their fresh pod production potentials and nitrogen benefits to the soil. The cultivar’s marketable fresh pods were harvested 4 times from April to May. Plants were sampled at the last harvest to quantify the faba bean cultivar’s contribution to soil N. Plant samples have been shipped to UC Davis Stable Isotope lab for N and 15N analysis. 


  • The above described trial is replicated in 2021. Pod production of the faba varieties will be quantified and plants will be sampled for nitrogen measurements. The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Fresh pod production of five large-seeded faba bean varieties:


  • Five food varieties of faba bean (Aguadulce, Grano Violetta, Masterpiece, Vroma, and Windsor) were planted in a field trial at Chico State Farm. The varieties were compared for fresh pod production, pod and seed qualities, and contribution to soil N (poster in the Results and Discussion).

2021: The above experiment is replicated at the following locations:

  • CSU Chico University Farm 
  • Cal Poly Pomona University Farm 
  • CSU Monterey Bay University Farm 

The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Faba bean cover crop termination time:


  • A field trial was conducted at the NRCS’s Plant Material Center at Lockeford, CA.  A faba bean variety was planted in a Complete Randomized Block Design to determine the best termination time of the faba bean cover crop. Plants were sampled for biomass and nitrogen. After termination, sudangrass was planted in the field, and forage yield and nitrogen concentration of sudangrass were quantified. 


  • The above experiment is replicated at the NRCS’s Plant Material Center at Lockeford, CA. The results will be demonstrated in the upcoming virtual field day event.  The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Nitrogen benefit of faba bean cover crop in orchards:


  • An experiment was conducted in a 5-years walnut to quantify the nitrogen benefits of the faba bean cover crop. The treatments of this experiment included bell bean only and bell bean in a cover crop mix.   

Faba bean nitrogen benefit in organic ricelands:


Lundberg Family Farm is an organic rice grower in northern California that grows cover crop mixes during winter months. In 2020, we sampled cover crops from fields under different rotations to quantify nitrogen fixation of faba bean under this unique cropping system. The samples have been processed and shipped to the UCD lab for N and 15N analysis.  


The fields were sampled in 2021 and samples have been processed and shipped to UCD for N and 15N analysis. The results will be demonstrated in our 2021 virtual field day event. The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Response of faba bean cover crop to soil nitrogen: 


  • In collaboration with Chico Flax, a field trial was conducted at the grower’s site to quantify the response of faba bean to soil nitrogen. In a completely randomized design experimenter, a Windsor variety was planted under 4 rates of (0, 50, 100, and 150 kg N/ha). The outcomes will determine the benefits of faba bean in soils with high levels of nitrogen.  


  • The above experiment is replicated in 2021 and plants have been sampled for biomass and nitrogen. The field will be demonstrated during the 2021 Chico Flax field day event,  and to attendees in our virtual field day event.  The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Response of faba bean to inoculation with different rhizobia:


  • Two food varieties of faba bean were inoculated with two different rhizobia inoculants. The field will be sampled for yield, nitrogen fixation, and fresh pod production.  The results will be presented at the 2021 ASA annual meeting in Salt Lake City

Fresh pod yield of faba bean on large scale:


  • In Collaboration with Maciel Fields, a Windsor variety was grown in one acre land of their field.  The plan was to quantify the yield and economic benefits of faba beans on large scale, but unfortunately, we had to terminate the field due to the lack of labor for harvesting and lack of demands for the beans during the COVID pandemic.


  • In Collaboration with Kammelshoue Farms, we have grown about 0.5 acre faba bean between rows of a young orchard to quantify fresh pod production, economic benefits, and nitrogen fixation of faba bean in young orchards. This experiment will also test the feasibility of growing faba bean as alley cropping.    
  • In collaboration with Jesus Center Farm in Chico, we have grown about 0.5 acre faba bean. The field will be harvested for fresh production, economic values, and cost of production.   

Consumer awareness survey:


  • Dr. Maria Giovanni and her graduate student are developing a survey to collect consumer knowledge and expectation of faba bean foods. The survey is being developed by consulting three focus groups, which were recruited from CSA members, farmers’ Master Gardeners, Farmer’s Market consumers, and social media. The groups were interviewed online and the data is used to construct a comprehensive survey for consumer knowledge and acceptance of fava beans. Despite differences in opinions and understanding, the interview results were used to develop six common themes among the groups: preparation methods, recipes, convenience, the success of fava bean in the marketplace, promotion of fava bean, and cannot locate fava bean. These findings were used to construct a survey, which will be distributed to a larger population. The survey results will be presented at the 2021 ASA annual meeting in Salt Lake City

Faba bean familiratiy survey:

  • Dr. Negahban developed and executed a survey during the CA Plant & Soil Conference (Fresno, 2021) and evaluated the familiarity of attendees (Farmers, Researcher & University Professors, Extension specialists, Students, and Others) with faba bean as food and cover crop. The survey results will be presented at the 2021 ASA annual meeting in Salt Lake City

Faba bean cost /benefit analysis:

  • Drs. Houk and Hejazi are reviewing the existing literature regarding the cropping budgets for other plant species with similar general practices to develop formal economic evaluations of faba beans. Since there is no data on faba bean production, they are working closely with the project team to ensure correct information is being collected from ongoing field trials. The on-site production collaborators are collecting data on (1) production operating costs and material (e.g., land preparation, seed, irrigation, fertilization, pest management, harvest, yields, returns, etc.); (2) labor, equipment, and interest on operating capital; (3) cash overhead; and (4) non-cash overhead.   
Research results and discussion:

Fresh pod production (variety trial, Chico, CA) 

The average yield of five large-seeded faba bean varieties in Chico, CA in 2020. Harvest 1, 2, and 3, are respectively April 20, April 29, and May 12


Preliminary results of our variety trial in Chico, CA show that fava bean varieties produced 3.8 to 8.9 tons of marketable fresh pods in three harvests (April 20th, April 29th, and May 12th of 2020). The varietal variations for pod production at different harvesting times are related to their flowering and plodding dates. 

Although all these five large-seeded varieties grew well and produced similarly large biomass (data presented), they were different in pod production. The highest fresh producing varieties were Windsor (8.7 t/ha) and Vroma (8.9 t/ha).  From these two varieties, Vroma had a higher yield in the first harvest (43% of the total pod yield) and Windsor produced more pods at the end. These preliminary results suggest that Vroma is more suitable for dual-purpose crop food and cover crop than Windsor because it reaches its maximum production early in the season.  From the other three varieties, Grano Violetta produced 66% of its total pod in the first harvest. Grano Violetta and Vroma are both good candidates for places that growers need to terminate the crop after the first harvest.  

Pod quality (variety trial, Chico, CA) 

The bean quality parameters of five large-seeded faba bean varieties in Chico, CA in 2020.  

Variation of fava bean varieties bean quality in three harvests (April 20th, April 29th, and May 12th of 2020). 

The 2020 results show that pod dimensions (length and height) are less affected by harvesting time than the beans fresh beans. 

Termination time of faba bean cover crop


Late termination of faba bean cover crop resulted in more biomass production compared to early termination. The higher biomass of faba bean because of late termination can increase the yield of succeeding crops in rotation. 

Fava bean familiarity survey results  



Research conclusions:

Our research has not concluded yet, but our preliminary observations suggest that:

  1. Fava bean has great potential as a winter crop in northern California. Considering that most of the faba bean growth and yield formation cycle occurs during the rainy season, this crop offers the highest water use efficiency compared to other legumes and pulse crops in the region.
  2. The existing faba bean food varieties allow adoption of faba bran to different cropping systems to meet termination time. 
  3.  There is a significant interest in the community and local growers to learn about the crop and its benefit. Our interaction with growers suggests that they would grow faba bean if they find a sustainable market for pods, grains, and seeds. 
Participation Summary
4 Farmers participating in research


Educational approach:

Students training:

Several undergraduate students and two graduate students have been directly involved in this research. Undergraduate students are hired to help with day to day tasks, such as plot management, weeding, irrigation, harvesting, sampling, and sample processing. In addition, each of them is given a small project within the scope of the main project to practice and learn about research. Students are responsible for collecting and analyzing data and present it in professional meetings. Below is the list of past and upcoming presentations. Details of undergraduate research activities can be found on our web page –> Link 


  • Consuelo Baez Vega, Distribution of drilled plant species with different seeds size and density in mixed cover crops, CA Plant and Soil Conference, Feb 4 & 5, Fresno, CA
  • Saul Estrada, Quantifying nitrogen removal from fava bean harvest, CA Plant and Soil Conference, Feb 4 & 5, Fresno, CA
  •  Saul Estrada, Quantifying Nitrogen Removal from Fava Bean Harvest. ASA-CSSA-SSSA International Annual Meeting, Nov. 10-13,  San Antonio, Texas
  • Saul Estrada, Quantifying Nitrogen Removal from Fava Bean Harvest. 2019 WSCS Annual Meeting, June 25-26, Columbia Basin College, Tri-Cities, WA
  • Steve Wallin, Effect of Cover Crop Fava Bean Variety and Termination Time on Forage Sudangrass. ASA-CSSA-SSSA International Annual Meeting, Virtual, Nov. 9-13
  • Hunter Andrade and William Perez-Rios. Effect of nitrogen rates on fava bean yield and biomass production. ASA-CSSA-SSSA International Annual Meeting, Virtual, Nov. 9-13. 
  • Johnny Sanchez and Consuelo Baez Vega. Fava bean weed management and the impact on nodule formation and vegetative biomass. ASA-CSSA-SSSA International Annual Meeting, Virtual, Nov. 9-13.
  • Consuelo Baez Vega, Morphological differences in fava bean plots based on the effect of weed management practices. ASA-CSSA-SSSA International Annual Meeting, Virtual, Nov. 9-13.
  • Ana Medic. Significance and Impact of faba bean as a cover crop, whether monocrop or intercrop, in California orchards. ASA-CSSA-SSSA International Annual Meeting, Virtual, Nov. 9-13.

2021: The following titles are planned to be presented at the 2021 ASA meeting in Salt Lake City.  

  1. Fresh pod production potentials of fava bean varieties in northern California – H. Zakeri
  2.  Fava bean varieties yield and nitrogen fixation in organic farms – A. Zepeda  
  3. Fava bean consumers survey – M. Mcandrew 
  4. Decomposition and mineralization rates of fava bean, pea, and wheat residues – H. Coulter   
  5. Nitrogen fixation of fava bean in riclends – S. Jackson
  6. Performance of Fava N in soils with high N content- W. Perez 
  7. Agriculture professionals and farmers understanding and expectation of fava bean as a cover and food crop in northern California – Gallaty
  8. Effects of rhizobia inoculant on fava bean nodulation, N fixation, and fresh pod production – K. Holguin

Training students in other campuses

  • One faculty and two undergraduate students at Cal Poly Pomona have conducted a field experiment to compare different fava bean varieties for pod production and nitrogen benefit 
  • One faculty and one undergraduate student at CSU Monterey Bay have conducted a field experiment to compare different fava bean varieties for pod production and nitrogen benefits

Graduate students: 

In collaboration with Dr. Giovanni from the Food Science department, a graduate student is recruited to study the factors that limit the consumption of fava bean foods in the US. In addition to her coursework and developing the survey, the student has made foods from faba bean and demonstrated at Chico Farmers’ Market.  Below is the list of her presentations: 

  • Madeline McAndrew, Consumer Awareness of Fava Beans: Nutritive Properties, Consumption, and Preparation Methods, 2021 This Way to Sustainability Conference (online). Chico, CA 


Educational & Outreach Activities

3 On-farm demonstrations
1 Online trainings
1 Published press articles, newsletters
1 Webinars / talks / presentations
3 Workshop field days
1 Developed the fava bean research website

Participation Summary

4 Farmers
5 Ag professionals participated
Education/outreach description:

Field day demonstrations:

  • 2020: The Lockeford trial (termination study) was presented to growers on March 5, 2020. 70 people attended the field day from 9:30 to noon, our plots were demonstrated at the end (11:30 to noon). In the presentation, the potentials of winter fava bean to build soils and support vegetable production and the importance of cultivar choice and management strategies (e.g. termination time/method, harvest scheme, planting time) was presented to the audiences which included farmers, NPOs, and private businesses.  Two other field days were planned to demonstrate the field trials at CSU- Chico and at Chico Flax locations, but both events were canceled due to the Stay-Home order in California.  
  • 2021 Virtual field day demonstration: A virtual field day demonstration is planned for May 7, 2021. This event includes presentations about the latest updates on our fava bean research. The 2021 field day details can be found on the NRCS website –> Link
  • 2021 Chico Flax field day demonstration: A field day is planned to demonstrate the field trial at Chico Flax on May 1st, 2021.  

Professional presentations

  • Kyle Brasier, Building Better Legumes for Regenerative Cropping Systems, This Way to Sustainability Conference. March 26-27, 2020, Chico, CA https://www.csuchico.edu/twts/session-descriptions.shtml#legumes.  Although the conference was administrated online, he had about 40 audiences. Due to the online nature of the conference, the audiences were not surveyed. 


  • Our work was cited in the article “Take a run at alternative crops” in Western Farmer-Stockman –> Link 


Farmers collaborators:

A farmer (Dax Kimmelshou),  a non-profit organization (Jesus Center), and a company (Sierra Nevada Brewing Company ) are growing faba beans in their fields. We will use these farms to quantify faba bean production potentials, costs, and potential economic benefits of faba bean in different cropping systems. 

Educating California Communities: 

Visiting farmers market: We have visited the Chico, Sebastopol, and Los Angeles Farmers’ Markets to inform the communities about the benefits of fab bean to soil and introduce some faba bean food to them.  In addition to demonstrating foods and providing pamphlets about fava bean benefits and food recipes, we give away more than 3000 seed packs of faba bean to people across California. Seeds paks had the necessary information about growing faba bean at home.   

Link to the pamphlet that was given to people at the Chico Farmers’ Market >>> Link  


Learning Outcomes

70 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
Key areas taught:
  • Faba bean cover crop termination time

Project Outcomes

4 Farmers changed or adopted a practice
3 New working collaborations
Project outcomes:

Changing farming practices

  1. Sierra Nevada Brewery:  The brewery produces thier barley and hops organically and mange their soil fertility by adding compost and cover crop.  They are growing a small area of three faba bean varieties to learn about the crop and possibly expand it in the future
  2. Chico Flax: Chico Flax has extensively collaborated with us in this project. They have grown faba bean only plots, and also cover crops containing faba bean seed. They have helped to promote faba bean in northern California by presenting faba bean in their field day demonstrations.  
  3. Kimmelshoue Farms: Kimmelshoue farm grows beans between young orchards (alley cropping). They planted two food varieties (large-seeded) of faba bean in a limited area of a young orchard (between trees) to learn about the crop and its potential benefits.  
  4. Jesus Center Farm:  Jesus Center farm is an organic farm and produces vegetables for their kitchen. They grow a field of faba bean to learn about the crop and its potentials as food and nitrogen crop. 

New collaborators: 

  1.  Cal Poly Pomona 
  2. CSU Monterey Bay 
  3. University of Nevada, Reno


Success stories:

Spreading beans

When COVID pandemic started and we faced restrictions of working with students and CA community, the project manager, Dr. Kyle Barsier, launched his Community Science Project (Link) to connect with people. His goal was to promote faba bean as a food crop, and teach the community about the science of nitrogen fixation. He and his students packed faba bean seeds and shipped to people around California and other states. The map below shows the places that they shipped seeds. In this project, we had agriculture teachers who adopted the project as a class project to teach their students about food production, legumes, and the nitrogen fixation process.   

Developing food:

A chef was recruited to develop recipes and make dishes from faba bean pods and flour. She developed recipes and made a few dishes. The preliminary products were very satisfactory. The goal was to present the products at Chico’s Farmers Market, but the event was canceled due to the COVID pandemic. 

          Faba bean pizza crust



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.