Innovative practices cut potential phosphorus runoff, soil erosion
BALDWIN, Wis. — Farmers in a five-county area in western Wisconsin are showing the value of non-traditional farming practices, and their efforts are reducing potentially harmful runoff into streams and lakes, a new analysis shows.
Field practices adopted by the farmer-led watershed conservation group’s livestock and crop farmers are significantly reducing the chance of harmful runoff into streams and lakes, according to research shared by the state Department of Agriculture, Trade and Consumer Protection, the University of Wisconsin-Madison, and The Nature Conservancy.
Using data about farming practices among members of the Western Wisconsin Conservation Council (WWCC), the analysis calculated an estimate of the potential impact of various practices compared to more conventional methods typical to Barron, Dunn, Pierce, Polk and St. Croix counties. The findings show, for example, that the farmers using strip-tillage and no-tillage practices on typical crop and livestock operations potentially reduce phosphorus runoff from farm fields by 44 percent and soil erosion by 48 percent.
Stopping phosphorus and soil sediment from leaving farm fields improves water quality. For example, every pound of phosphorus that reaches a stream or lake can potentially feed 500 pounds of algae, degrading the waterway.
"As a group, we are working for continuous improvement in water quality and soil health by using a wide array of best management practices,” Todd Doornink, a dairy farmer in Baldwin who leads WWCC, said. “These results measure our progress, and we will continue to push ourselves to be better stewards of the land every day.”
The four-year-old nonprofit farmer-led watershed conservation group has grown to 40 members who represent 28,250 acres and 6,800 dairy animals, beef cattle, pigs, goats and other livestock. The group also has members who farm vegetables and fruit. The council collaborates with university researchers, environmental groups and community leaders. They hold field days to demonstrate various practices, and they participate in scientific studies, notably a well-water testing study with the University of Wisconsin-River Falls.
"We’re excited to work with the WWCC farmer members who are not only making changes in how they farm and manage their soil but sharing their data to illustrate their impact,” said Steve Richter, agricultural strategies director at The Nature Conservancy. “In 2020, we saw big increases in the number of farmers using advanced nutrient management practices and establishing grass waterways, and in the acres covered by those practices. I’ll look forward to hearing about the beneficial impacts of these practices on the environment and their farm operations at future field days.”
WWCC members are regularly practicing conservation techniques like basic soil sampling, nitrogen stabilization, nutrient management plans and split nitrogen applications. They are also figuring out how to make these practices financially sustainable through increased productivity.
WWCC farmers have made noticeable changes to their practices. The most recent numbers (2019):
- 15,800 acres of conservation tillage practices (either strip-till or no-till planting in spring)
- 27,400 acres covered by nutrient management plans
- 10,725 acres of cover crops
- 1,500 acres of low-disturbance manure injection
MORE ABOUT THE ANALYSIS
The analysis was completed as part of a conservation benefits tracking project initiated by the Wisconsin Department of Agriculture, Trade and Consumer Protection to evaluate impacts of the state’s Producer-Led Watershed Protection Grants Program. The initiative was developed in collaboration with the University of Wisconsin-Madison Department of Soil Science and The Nature Conservancy. Wisconsin’s SnapPlus nutrient management planning software was used to calculate the potential annual phosphorus loss and soil erosion on fields when farms include practices such as cover crops and reduced tillage.
While not every conservation practice provided significant reductions for each scenario, below are examples of the amount of phosphorus loss and soil erosion that can be avoided with the adoption of practices on agricultural landscapes in Barron, Dunn, Pierce, Polk and St. Croix counties. Acreages of practices are based on the average number of acres implemented on WWCC member farms in 2019.
It is important to note that the calculations below are based on comparisons of generalized systems, not actual farms, and do not take into account the other watershed variables that impact how sediment and phosphorus make their way into a stream or lake.
For comparison, a mid-size dump truck can carry 10 tons of sediment, and 1 pound of phosphorus in a waterway has the potential to cause the growth of up to 500 pounds of algae.
Dairy farm with a corn silage and alfalfa rotation adopting 715 acres of small grain cover crops following corn silage
- Phosphorus loss reduction: 1,466 pounds
- Soil erosion reduction: 1,416 tons
Corn/soybean farm adopting 903 acres of strip-tillage
- Phosphorus loss reduction: 2,646 pounds
- Soil erosion reduction: 2,655 tons
Corn farmer adopting 692 acres of no-tillage
- Phosphorus loss reduction: 1,163 pounds
- Soil erosion reduction: 796 tons