Evaluating the Environmental Benefits and Economic Opportunities of In-Vessel Composting Solid Dairy Manure

View the project final report

Commodities

• Animal Products: dairy

Practices

• Animal Production: manure management
• Natural Resources/Environment: windrow composting
• Soil Management: composting

Three dairy farms in the Yahara River watershed of Dane County, WI with high concentrations of livestock want to evaluate and demonstrate that windrow composting of bedded pack manure could potentially improve the long-term sustainability of their farms through the marketing of a value-added soil amendment and moving nutrients out of a phosphorus impaired watershed.

Endres Berryridge Farms, has three equal partners and owners: Jeff, Steve and Randy Endres. We milk 500 Holstein cows, raise 400 heifers and manage 1100 acres of cropland. We have liquid manure storage for all animals older than six months of age. Heifers that are six months and younger are housed in group pens bedded with corn stalks or straw along with some wood shavings. All cattle six months and older are housed in free stall barns with sand bedding. If funded, this project would allow us to evaluate if it’s possible to use bedded pack compost as the source of bedding for all the heifers prior to freshening. This would eliminate the use of sand and the generation of liquid manure from all our heifers.

The cropland is generally planted to 550 acres of corn, 300 acres of alfalfa and grass and the rest is a combination of soybeans and wheat. We use cover crops on all fields that are not alfalfa (about 600 acres) and use conservation tillage, strip tillage and no till depending on the land. We have previously worked on a wetland biomass project with Dane County to convert farmland back to wetland and use harvestable native grasses for livestock feed and bedding (this could be another source for composting material). We also host a USGS monitoring station that evaluates water quality and quantity from both tile and surface water runoff. 

This project will include a strong outreach and education component conducted by these three farms and our close relationships with Yahara Pride Farms and the Clean Lakes Alliance, two affiliated non-profit organizations that work to improve soil health and water quality in the Yahara River watershed. Yahara Pride Farms is a farmer-led organization that evaluates and promotes management techniques and technologies that can reduce phosphorus loss to the Yahara lakes. Over the past 5 years this program has evaluated new manure application methods (vertical manure injection), cost-shared the planting of cover crops, and developed and implemented a sustainable certification program that works with farmers to identify high-risk practices or settings.

The other partcipating farms include:
Scott Maier, dairy farmer, owner of Maier Farms and Treasurer of Yahara Pride Farms Board. Maier Farms will be a host site for the composting project and use the compost for bedding pack.

Jeremy Huffman, dairy farmer. Huffman Farms will also be a host site for the composting project and use the compost for bedding pack.

The Yahara Watershed faces immense soil and water quality issues because this area has high concentrations of dairy farms. As in other areas of the country, these dairies have been growing and consolidating over the past 15 years to the point where the investment in dairy facilities is extremely high. This watershed is blessed to have a high density of excellent dairy managers but that means the competition for land and the generation of livestock manure is intense. Further complicating the issues is that the Yahara River flows through the center of this watershed and this river feeds the chain of five lakes located around Madison. All of these lakes show signs of excessive phosphorus and sediment loading. Modeling efforts have been conducted by a variety of private and public agencies over the years leading to a study in 2011 that concluded that agricultural sources accounted for 70% of the phosphorus entering the lakes (Clean Lakes Alliance, Strategic Action Plan). While farmers and landowners throughout Wisconsin are under increasing pressure to reduce non-point sources of nutrients and sediments to waters of the state, farmers living in the Yahara Watershed are under an even higher level of scrutiny. This is why livestock farmers need to find solutions to issues associated with manure (winter spreading, storage, etc.) and all need to work together to improve the sustainability of agriculture in the region. Until we can control the weather, we can never eliminate the risks inherent to farming. But where possible we should modify our farming systems to be as protective of the environment as possible, while educating farm public about the economic and environmental benefits associated with conservation practices and the non-farm public about our efforts. This project would allow us to explore alternatives for bedded pack manure that is often hauled on cropland just prior to snowmelt. Livestock farmers face a dilemma in that once the spring thaw begins manure must be removed from cattle lots to keep cattle dry and healthy. However, in the upper mid-west this is the most critical period for nutrient loss and data from this region shows that the majority of phosphorus is lost in late February and March. An economical alternative to land spreading bedded pack manure is required if we hope to improve water quality in this region. Composting has the potential to reduce bedding costs, reduce the volume of liquid manure and to create a value-added product that could be marketed and sold if it is not needed for bedding. Through this project all three host farms would like to get the following questions answered.

1. Do we have alternatives to spreading bedding pack manure on fields in the winter by composting?
2. Does composting bedding pack manure give the farmers options to be able to sell their excess nutrients from their farms in the form of compost?
3. Can we develop a product that is marketable and profitable for our operations?
4. What are the economic benefits of using composted bedding pack manure? What are the environmental benefits?
5. Does composting help our watershed manage manure more effectively as a whole?
6. Are there disadvantages of using composted bedding pack on the herd?
7. Can we double the benefit of using corn stalk and straw by being able to re-enter it in free stall barns after the compost process?
8. Does spreading of bedded pack manure on cropland in the winter slow down the warming up of soils in the spring and can it delay planting?

The demonstration project will be conducted from April 1, 2015 to October 31, 2015. Evaluation of final product application will be completed September through November 2015. The Final Report will be completed by the end of December 2015 and may be amended based on additional findings during the Spring of 2016.

• Sampling and testing may be completed of each feed stock (bedded-pack manure and paper waste are two examples) for carbon to nitrogen ratio (C:N), major nutrients, pH, and micronutrients.
• Each farm will have a minimum of 2 windrows for analyzing
• Replications comparison may be based on the use or incorporation of additional feedstock to the particular farm’s bedded-pack manure.
• Windrows will be turned based on moisture level, temperatures reaching and exceeding 105 degrees, or requires aeration.
• Monitor compost daily for temperature, carbon dioxide accumulation, moisture percentage and visually evaluate for leachate, runoff, and steam generation. Approximately a 6-10 week process.
• Stop composting process once temperatures have stabilized or the windrows have the textural consistency the farm is looking for in bedding.
• Piles may be sampled and tested for similar properties as completed initially with the addition of biological tests.
• After the evaluations, we will share our evaluations, reports and gained knowledge through Yahara Pride Farms communications and events.