Valuable commodity found in compost manure
Loretta Sorensen for Ag Nutrient Management
Prairieland Dairy has turned what could be a liability into an asset at its 1,350-head Firth, Nebraska, dairy. Barns are cleaned with recycled flushwater, which runs to a separator. Liquids are pumped into a lagoon and land-applied, and solids are piled on a slab that slopes back into the pit. After approximately 10 days, the moisture level in the manure solids is 80 percent or less and the manure is composted in windrows by a Brown Bear PTO-PA 35C auger aerator attached to a farm tractor.
Dairy co-owner, Dan Rice, says it’s been nine years since they began using manure solids to create sterilized compost for bedding. In 2004, Rice and his partners determined that the use of sand bedding would improve milk quality and began looking for other uses for the compost they were creating.
“We were able to cut the dairy’s somatic cell count in half and we’ve developed a market for our compost,” Rice says. “Once we stopped using compost for bedding our cows, we started allowing local entities to bring in other sources of carbon for the compost pile. Initially, most of the compost we produced was used by local homeowners and landscapers for mulch on lawns and flowerbeds. More recently, we developed our own potting soil and growing mix, adding ingredients such as perlite and peat. Since we don’t own any cropland, all our manure goes into the compost.”
The compost pile is turned three times each week for six weeks. Through this process, the 80 percent moisture manure is dried into 30 percent manure compost. Prairieland Dairy’s compost has a 2:1:1 NPK rating and 95 percent coliform kill rate. The dairy received a grant to complete a feasibility study on how to market the compost. The recommendation was that they sell it in bulk.
Grass and leaves are the main waste products that small surrounding municipalities and individuals bring to Prairieland Dairy. A truck scale documents the weight of incoming waste and each entity is billed for the amount of product they dump.
“Typically, we don’t charge individuals who bring in waste,” Rice says. “For the municipalities, most of them were burning their materials before they started bringing it here. Air quality officials are frowning on that now, so this is a good alternative for them.”
The dairy has specific days and times when compost waste products are received. Since composting takes time, it is stockpiled for about a year before it’s sold.
“We always have some compost on hand,” Rice says. “Of course weather plays a role in how quickly it decomposes and is ready for use.”
In 2009, Prairieland Dairy began working with home and garden stores to sell bags of their compost. They bag their compost on site. The majority of what they produce is still sold in bulk to landscapers and goes out in semi loads.
“Landscapers also serve as resellers and they’re our second-largest market,” Rice says. “Homeowners are our third and smallest market. We’ve always been satisfied if we were able to break even on the operation because disposing of manure is so expensive if you don’t own land where you can distribute it. Since we started using food sources for compost, we see a potential for further development of the compost operation.”
“We believe there’s a great opportunity to bring in more food waste for our compost, which would allow us to produce compost on a larger scale,” Rice says. “As we continue to market the compost and make it a larger part of our dairy operation, we’d like to make a methane digester part of the process. That would allow us to use the heat and electricity the digester generates to operate the dairy.”
Rice doesn’t believe that a compost operation is a good fit for every dairy. Producers who use manure to fertilize crops are probably realizing a greater return by using it that way than by composting.
“If you’re not raising crops, waste becomes a huge issue for a dairy,” Rice says. “Disposing of it is very costly. We’ve been very pleased to be able to take something that could have been a huge cost factor and turn it into something that was no-cost with potential for profit. If you don’t raise your own feed and you’re located in an area where there aren’t many residents or small towns, selling compost may be problematic.”
Prairieland Dairy is a partnership that Dan Rice, a young Pennsylvania dairy farmer, initially formed with Dave and Cliff Obbink, natives of Firth. Two other dairies, Wil-Mar-sen Dairy of Beatrice and L.A.H. Eickhoff Farms of Falls City, joined the partnership and they expanded to 1,200 cows. Rice serves as the dairy’s manager and each of the other partners focuses on an element of the dairy they can specialize in, such as raising heifer calves, feeding out bull calves, etc.
Prairieland Dairy formed Prairieland Foods, LLC to offer specialized milk products that are source-verified and locally produced, such as milk from cows that don’t receive rBST or other production stimulants. The dairy bottles milk in corn-based biodegradable plastic bottles and markets their products in stores in Lincoln. ANM
