Along the banks of the Mississippi River in the driftless area of western Wisconsin lies Buffalo County. It is home to valleys of unsurpassed fertility, bordered by towering bluffs on all sides. Nestled in Waumandee Valley is Rosenholm-Wolfe Dairy LLP, a 550-cow and 500-head youngstock operation.
The formation of a larger dairy in this location presented some challenges, explained Loren Wolfe at the Midwest Manure Summit in Green Bay, Wisconsin, last month. In those challenges, the dairy found an opportunity to diversify.
Click here to learn more about the Midwest Manure Summit.
The farm is a partnership of two unrelated families – Loren Wolfe and John and Nettie Rosenow – that was formed in 1996.
The partnership owns 20 acres, the facilities, cattle and feed. Each partner retained ownership of the land they owned prior to the partnership and rents it to the dairy.
As the partners decided on the size of the dairy, they agreed to have 1,300 animal units (including replacements). Based on their location, they would have the land base to supply the feed required for this number but not enough acres for manure disposal, Wolfe said.
The Rosenows had been experimenting with compost, so the partners decided to build their manure system with compost in mind.
Flush water at 99 percent water is pumped back from the lagoon into holding silos, where it is mixed with some fresh water (about one-fifth of the total flush water used). From there the water is gravity-flushed down the barn aisles three times a day during milking.
The barns were built to slope to the center, where there is a reception pit located under the floor.
Water and manure from the reception pit are pumped over separator screens. The solid manure is deposited on the concrete below, and the water flows through the screens to the three-stage lagoon.
Lagoon water is used to irrigate approximately 750 acres of cropland. It is applied with a traveling gun onto hay fields after each cutting. Approximately 30,000 to 40,000 gallons an acre are applied per year, which meets the farm’s nutrient requirements.
“Most odor we have comes from when we flush our barn,” Wolfe said. “Once we irrigate it out, we can hardly smell it.”
The separated solids are left to drain a few days, and then dry sawdust manure from the maternity pen and calf hutches is mixed with the separator solids at a rate of two parts solids to one part dry manure.
This mixed product is hauled from the farm to the compost site in a box spreader.
The compost site is a three-acre blacktop slab located 600 feet north of the dairy barn.
They do not compost in the winter but use the compost site for storing the separated solids until they can be field-applied in the spring.
When the weather is nice, the box spreader lays the solids out in windrows, which are then left to heat up to 132ºF. This may take three to seven days, depending upon moisture of the product and the outside temperature.
The temperature is needed to kill weed seeds and any disease-carrying organisms. Once 132ºF is reached for a few days, the windrows are turned (or fluffed up) with a self-propelled compost turner with swinging knives. This allows the carbon dioxide to be let off into the atmosphere and for oxygen to enter the solids.
The windrows are turned every week for three to four months. The finished product is black in color and smells like freshly turned ground. It contains 75 percent cattle manure and 25 percent sawdust used for
bedding.
The investment cost for composting varies by farm, Wolfe said, but for them it totaled $535,000, approximately $1,000 per cow, in 1997. (See Table 1 for a breakdown of those investment costs.)
“If you’re going to sell (compost) as a business, you’ve got to market it,” Wolfe said. They attend organic conferences and garden shows to promote their product, which does meet the National Organic Practices (NOP) standards.
In 2006, they started selling potting soil at the request of their customers. Using the compost turner, the compost is mixed with perlite, sand, moss and a few other materials to create the potting soil.
The compost and potting soil is all packaged on the farm in 1,000-pound plastic tote containers, 50-pound bags and 20-pound bags.
All compost is sold off the farm, amounting to 8,000 tons in 2012. Not only does this allow the farm to meet its nutrient management plan requirements, it also provides an additional income stream.
“It has become extremely profitable for us,” Wolfe said. “I’m glad we were selling compost in 2009.” PD
Karen Lee
Editor
Progressive Dairyman
