Implementing Whole Farm Cycling of Nutrients and Carbon with Orchard Waste in Walnut & Cherry Production in Central Valley CA

Progress report for FW22-388

Project Type: Farmer/Rancher
Funds awarded in 2022: $24,961.00
Projected End Date: 05/31/2024
Grant Recipient: John Eilers Farms
Region: Western
State: California
Principal Investigator:
Franz Eilers
John Eilers Farms
Expand All

Project Information

Summary:

Central Valley’s smaller family orchards are facing severe economic and environmental pressures. With new regulations and increasing input costs, these growers are experiencing unprecedented challenges to their survival. The applicant’s farm is transitioning now to the next generation and is sharply aware that practices must change and innovate in order to remain sustainable. By law, agricultural burning is being phased out, and ordinances controlling and monitoring nitrogen application rates are coming into effect. The practices of burning organic waste and excessive nitrogen inputs are recognized  as not sustainable and generally harmful to the environment, and to farming.

 

This project implements an alternative through nutrient-cycling a season’s orchard-waste, cover-crop plant mass and local agricultural waste into compost that then is returned to the orchard. The design also captures carbon from orchard-waste: prunings and dead trees; better preserves nutrients from cover-crops; and proposes local food processor culls and manures. Compost will be built with the advice of consultants and scientists familiar with biodynamic compost methods. The aim is to minimize off-farm inputs, which create a fragile economic and biologic system, and to enlarge the intrinsic nutrient and carbon base within a stable farm system. This project will be shared through site-visits with San Joaquin County growers, biodynamic growers of Northern California, and identified stakeholders. Efforts will be measured through team observations, data collected, and feedback from stakeholders.

Project Objectives:

RESEARCH

  • (a) Develop a pilot compost program, for 40 acres (20 walnut / 20 cherry), on-farm that can incorporate the acres’ woody mass orchard-waste back into a nutrient-cycled soil amendment. This compost offers an alternative to open burning and an opportunity to offset carbon inputs and nitrogen fertilizer applications, the latter which are becoming more costly and threatening to ground water quality. A largely self-sustaining, closed-cycle nutrient cycle has been demonstrated for organic-biodynamic farming (Kaffka & Koepf), and conversion to biodynamic methods emphasizing compost use over imported fertilizers has been shown to significantly reduce tile-drainage nitrate collected across farms (Goldstein, Scully, Kohl and Shearer).
  • (b) Capture carbon from orchard wood waste. In composting this waste we aim to capture at least 50% more carbon than the 0% carbon captured now in open burning practices.
  • (c ) Seek the reduction of non-organic fertilizer inputs currently contributing to surface and groundwater nitrogen contamination through cycling nutrients with biodynamic methods.
  • (d) Better utilize nutrients available in orchard-waste, cover-crop and other agricultural waste materials through composting them. 
  • (e) Evaluate the feasibility of the project as a cost effective and beneficial solution to identified needs within the resources accessible to the Eilers and for comparable farms in San Joaquin County.

EDUCATION

  • (a) Evaluate project replicability for comparable Walnut and Cherry orchards in Central Valley California. 
  • (b) Open a research conversation about the possible application and benefits of biodynamic methods in Walnut and Cherry orchards in Central Valley CA.  Sharing this project with the growers in Northern California offers new frontiers for the application of closed-cycle biodynamic methods in large scale agriculture. Wine growers have had great success with it in recent years, both for benefits to sustainability, product quality and value. However, these methods used on vineyards could be translatable and have not been seen in nut and stone fruit growers yet in the Central Valley.
Timeline:

Cooperators

Click linked name(s) to expand/collapse or show everyone's info
  • Marney Blair - Technical Advisor
  • William Brinton, PHD - Technical Advisor
  • Franz Eilers - Producer
  • Emma Wade - Producer (Educator)

Research

Materials and methods:

Research Objectives:

  • (a) Develop a pilot compost program, for 40 acres (20 walnut / 20 cherry), on-farm that can incorporate the acres’ woody mass orchard-waste back into a nutrient-cycled soil amendment. This compost offers an alternative to open burning and an opportunity to offset carbon inputs and nitrogen fertilizer applications, the latter which are becoming more costly and threatening to ground water quality. A largely self-sustaining, closed-cycle nutrient cycle has been demonstrated for organic-biodynamic farming (Kaffka & Koepf), and conversion to biodynamic methods emphasizing compost use over imported fertilizers has been shown to significantly reduce tile-drainage nitrate collected across farms (Goldstein, Scully, Kohl and Shearer).

Methods:

August/September 2022: *New start date* 

Consulted with Blair by phone and email.

Pruned & cleaned dead wood out of cherry acreage. Moved this wood material out of the orchard with an orbital brush rake and/or pushed it out with a front load rake on a tractor. Wood material waited in a windrow on the edge of orchard for a time when chipping was possible.

Prepared the compost site, a 2+ acre area, currently fallow and with easy road access. This included discing and floating the area, and setting up irrigation lines for compost windrows. (This compost site was established and is being used for a larger composting effort, but it was decided better to make the site for this SARE project closer to the field that the waste material is coming out of to minimize transport efforts & costs.)

August through winter research was done into what method, how and when would be best to chip the material. The orchards for this project are mature, so there are always a number of full trees that come out and stumps are best chipped in a tub grinder. There was also a concern for the effort it would take to chip by other means. Moreover the quality of chip was being considered. A smaller-finer chip is preferred for composting. The search finally came to find a company that has a 8 ft tub grinder that could come into the field and chip on site this was finally scheduled for the first week of May, 2023.

Principle Investigator(PI) applied and received a tractor recycling incentive from the NRCS which facilitated the purchase of a better bucket and machine for dealing with the compost making process. Additionally PI applied to the CA state Healthy Soils incentive program to help offset the purchase of a compost turner. This equipment was acquired and is to be used for this project.

October/November 2022:

Took out and cut up dead trees in Walnuts & Cherries. Removed from the orchards to wait for chipping. Consulted with Blair by phone & email. Planted a soil builder cover-crop with a no-till seed drill. Windrows sat waiting for chipping in the spring.

April 2023:

A method was developed for harvesting the cover crop in April by first experimenting on other acreage and the larger compost project site. The method settled on was 1) mow cover crop down with a rotary mower (this cuts it kind of like hay), 2) rake it up into a row driving an orbital orchard rake on both sides of the cut material, 3) mow over the pile with a flail mower to mulch it more, 4) push it up with a bucket into piles at the end of each tree row, 5) scoop it with a rake on a tractor to the windrow.

May 2023:

The small tub grinder came and chipped up all the material. The result was a nice fine chip. Chip was in a massive mountain at edge of field and was moved one bucket at a time to the windrow site. One bucket full was carefully placed one after other, making one approximately 100 yard windrow. Then these chips were watered with a pressurized 1000 gallon bubble tank by walking along with a large hose. Simultaneously, in the same day, the cover crop was harvested. (The cover crop in the cherries did not take well. It was seeded a week or so later and may have been affected by the heavy rains of 2022. The cover crop in the walnuts did very well, and grew a good 7 feet tall. This 20 acres was plenty of green material to match the wood chips. No second pile was built for wood chip and local produce culls as written in original proposal.) A layer of cover crop was placed on top of the wood chips at about a 1:1 ratio. Blair had advised when looking at the cover crop to do either a 2:1 wood to greens or towards a 1:1 ratio. Cover crop was a bit more mature than desired and starting to form seeds. For this reason there was a fear nitrogen was starting to leave the greens. This layer of green on top of the chips was also watered with the bubble tank. an additional layer of chips and sprinkling of greens was added.

Blair came for 1st site visit on day chips were finished and cover crop was cut.

After being watered the wood chips and cover crop were immediately turned with the compost turner attached to a tractor on creeper gear. In this turning the piles were watered again with a biodynamic cow gut ferment provided by Blair. The biodynamic "500 horn manure preparation" spray was also applied to the piles as a compost tea. 

Plant samples of the cover-crop will be sent to WEL for nutrient content testing (total-N, P, K).

This first couple of weeks is crucial for maintaining temperature and moisture. PI and advisers in daily communication. Daily temperatures and moisture readings are taken of the pile using a prob temperature and moisture sensor made for this purpose. Perfecting and managing water application must be developed. Plastic lines with sprinklers were not possible on this location. The 1000 gallon bubble tank used to soak the piles. The piles sit and receive watering, turning & management as advised.

June 2023:

Blair will  come for visit 2. 

The piles sit and receive watering, turning & management as advised.

July/September 2023: Turning, watering and management.

October/November 2023: Soil samples from each plot will be taken for WEL to get a baseline for soil organic carbon and selected nutrients present before compost. When the compost is ready, it will be sampled for WEL and then spread back onto the orchards the materials were harvested from. A compost spreader will be rented to do this. Blair will visit. 

December 2023 / January 2024: Findings analyzed, final reports built and shared.

The PI will keep a monthly observation log in google docs that is accessible to advisors.  From this, advisors will give guidance throughout the process, ensuring its success in design and beneficial outcome. Throughout the process, samples sent to WEL will track the pathway of nutrients through the process and quantify the nutrient and carbon budget for the farm per acre.  

Materials: Chipper, spreader, watering equipment. Available on farm pruning and cutting equipment, tree prunings and dead growth, tractor with brush rake, trailer for transport, bucket tractor with creeper gear. Materials needed for shipping to WEL.

  • (b) Capture carbon from orchard wood waste. In composting this waste we aim to capture at least 50% more carbon than the 0% carbon captured now in open burning practices.

Methods Continued: Samples sent to WEL will measure carbon present in wood chips before and after composting to evaluate the mass retention .

 

Materials: included in (a)

  • (c ) Seek the reduction of non-organic fertilizer inputs currently contributing to surface and groundwater nitrogen contamination through cycling nutrients with biodynamic methods. 

Methods: Compare fertilizer input needs during the duration of the project and compare to two previous years before compost application. Compare soil samples with previous samples on file.  Evaluate if there was a reduction and if there were any savings. 

Materials: included in (a) + Fertilizer inputs amounts and costs and soil sample records available 2020-2021. 

 

  • (d) Better utilize nutrients available in orchard-waste, cover-crop and other agricultural waste materials through composting them. 

 

Methods: Utilizing nutrient cycling through biodynamic methods and WEL’s testing program to collect data and analysis.

 

Materials: included in (a) 

 

  • (e) Evaluate the feasibility of the project as a cost effective and beneficial solution to identified needs within the resources accessible to the Eilers and for comparable farms in San Joaquin County.

 

Methods: Team will have meetings to evaluate this objective in August, November 2022, May, October 2023. These meetings will examine the design, current successes and problems, and anticipate challenges with methods, materials and design. These evaluations will be used to document the progress of the project and help in the end determine the cost value benefit. 

 

    Materials: Shared google doc, Conference call or video. (No costs associated.)

Participation Summary

Research Outcomes

2 Grants received that built upon this project

Education and Outreach

Participation Summary:

Education and outreach methods and analyses:

Project has not yet reached the education and outreach phase. Scheduling for site visit with BDANC is possibly happening in early June and a field day with local growers is in the process of being scheduled.

Education and outreach results:

As project is just now in the first week of actually building the compost, there are no results yet to engage education and outreach objectives. We are making observations and notes in anticipation of meeting these objectives in the coming months. 

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.