Late September’s torrential rains are a good reminder to take a step back and look again at the benefits of pasture-based dairying. The Minnesota Institute for Sustainable Agriculture and the Land Stewardship Project have compelling data showing the positive impact of grass-based farming, including short-term benefits like cutting erosion and runoff by 50 – 80% immediately, and long-term benefits that include improved habitat for birds and wildlife, significant greenhouse gas reductions, and greatly reduced volume of flooding.
Western Minnesota is covered with corn and soybean monocultures – a perfect environment for large-scale runoff during seasonal cultivation and in heavy rain. It all drains into the Minnesota River and into the Mississippi River at Fort Snelling below Minneapolis, and then down the middle of the continent to the Gulf of Mexico.
Southeastern Minnesota is checkered with bottomland farms and ridgetop fields that drain through creeks and wetlands into the Mississippi below Red Wing down to Houston County south of La Crosse. All that prime prairie topsoil, millions of years in the making, gradually drains off the corn and soybean fields into the creeks and rivers and ends of silting in the once mighty and untamed Mississippi down into the once-fertile Gulf.
PastureLand farms are a very, very small factor in the erosion equation, but studies have shown that not only do our farms produce less runoff, but creeks entering our farms are actually cleaner going out than coming in. If more dairies used pastures the Minnesota River would be cleaner, the Mississippi would run cleaner and deeper, and the Gulf of Mexico – fragile already from years of environmental degradation and insult from the recent Deepwater Horizon oil spill – would gradually begin to heal itself.
The article below highlights ways that pasture-based farming can help farmers meet the demands of the Clean Water Act, and also reminds us why by supporting grass-fed meat and dairy, consumers are not just putting healthier foods in their bodies, but they are making a tremendous positive impact on the environment.
Pasture-raised farming:
An innovative strategy for farmers to comply with the Clean Water Act
How can the Clean Water Act influence farming practices?
Section 303 of the Clean Water Act requires states, territories and tribes to identify and list lakes, rivers and streams that are not suitable for designated uses — recreation, wildlife, and drinking water, for example — because of excess pollutants. When a body of water does not meet water quality standards for the designated uses, then states, territories or tribes are required to establish a total maximum daily load (TMDL) for the specific pollutants considered to be in violation. The goal of establishing a TDML is to help comply with the Clean Water Act by limiting the amounts of a specific pollutant from point (e.g., municipal wastewater systems) and non-point (e.g., lawns and farms) sources. Common problems related to TMDLs in areas with farms include runoff of sediment, phosphorus, nitrogen, and fecal coliform bacteria.
How can pasture-raised livestock systems help communities meet TMDL load requirements? Because pasture-raised livestock systems keep soil in place and reduce input demands, they reduce the amount of sediment and fertilizer that leaves the farm and pollutes water in several ways:
• Reduced sediment loss — Farming systems relying on grass and permanent cover can effectively reduce erosion, especially when compared to row crops and continuous grazing systems. Healthy grass and other perennial covers have great power to absorb water and hold soil in place, which reduces wind and water erosion that happens during large storms and throughout the year.
• Reduced reliance on highly fertilized feed crops — Feeding animals grass translates into fewer row crops, which are used to grow food for animals raised in confinement, including large factory farms. The reduction in row crops can lead to less fertilizer and herbicide use, less pollution and reduced greenhouse gas emissions (from the nitrogen as well as fuels needed to produce and distribute the fertilizers and grow the feed crops).
Pasture-raised livestock systems make it economically viable for farmers to maintain permanent perennial cover on the landscape, which increases the soil’s water-holding capacity and helps recharge the groundwater supply. Landscape cover also filters nutrients before water reaches streams, lakes, and other important bodies of water. A study of farms in southern and western Minnesota, using monitoring and long-term modeling, predicted that sediment, nitrate-N, and phosphorus runoff from pasture-raised livestock systems would be significantly lower than corn systems when rains were hard enough to cause erosion. This pattern was expected to increase dramatically during heavy rains.
Continuous grazing v. raising livestock on rotational pastures
Usually, continuous grazing systems involve releasing livestock into an open pasture during the growing season. The animals are allowed to roam the entire pasture and sometimes have free access to stream corridors, which can lead to overgrazing, erosion, and water pollution.
Rotational pasture livestock systems involve moving cattle into different areas to control how the land is grazed, which results in more efficient land use and less water pollution.
Can pasture-raised livestock systems reduce fecal coliform bacteria contamination?
Fecal coliform bacteria (which includes Escherichia coli) come from animal and human feces,1 and measuring them is one way to tell how much manure has washed into various bodies of water. Knowing how much manure is reaching streams, lakes, ponds and rivers is important because too much can cause human and animal health problems. A study conducted in Minnesota found that fecal coliform levels in waterways were consistently lower in rotationally grazed sites than in continuously grazed sites.2
Perhaps a more telling fact about the roles that pasture-raised systems can play in reducing fecal coliform bacteria in waterways involves the Mississippi River. The Minnesota Pollution Control Agency (MPCA) lists 20 stream reaches in the Lower Mississippi River Basin in Minnesota as impaired for swimming under Section 303(d) of the Clean Water Act. The main cause is excessive amounts of fecal coliform bacteria. Many of the streams in the area also have excessive levels of sediment, nitrogen and phosphorus pollution — all are associated with farm and residential use.
Citing evidence generated by the study of runoff from farms in southern and western Minnesota using rotational grazing, the MPCA included rotational grazing as an approved implementation practice to reduce fecal coliform in streams. Grazing also reduces sedimentation, turbidity and associated pollutants. This can help communities meet TMDLs and leads to improvements in the health of streams and rivers — and for the wildlife that live there.
Does pasture-raised farming offer other benefits to farmers?
Aside from helping comply with the Clean Water Act, shifting to pasture-raised livestock systems makes sense for farmers logistically and financially. Studies show that livestock production based on grass dramatically cuts the cost of an operation’s most expensive input: feed. Because pasture-raised operations also reduce the need for expensive housing and manure handling facilities, they are also much cheaper to set up and manage. Additionally, farmers who graze can get cost -share or other funding through various farm programs, such as EQIP, the Grassland Reserve Program and the Conservation Security Program, when implemented.
How do pasture-raised livestock systems work?
Raising animals using systems that utilize planned rotations allows grass to recover completely between grazing periods, spreads manure evenly over the land, and the fulfills animals’ nutritional requirements. These systems involve dividing a pasture into a series of smaller grazing areas or “paddocks,” and farmers move cattle among the paddocks to control how the land is grazed. The farmer allows plant growth to determine when cattle are moved and to which paddock they go.
- E. Coli is a common strain of fecal coliform bacteria, and is one of the markers used to determine whether or not a body of water is safe for recreation. See www.epa.gov/OWOW/monitoring/volunteer/stream/vms511.html for more discussion and guidance on sampling methods.
How is pasture-based farming good for the environment?
Research shows that converting a portion of corn and soybean crops — ingredients found in typical confined factory farm feeds — to diverse rotations including pastures has substantial environmental benefits.4 They can be:
• Soil erosion reduction of 50 to 80 percent.
• Pollutant run-off cut in half.
• Small to moderate flooding, resulting from farmland run-off, reduced by over 30 percent.
• Bird and wildlife habitats increased by five times.
• Greenhouse gasses reduced by up to 40 percent.
SOURCES 1. Digiacomo, G. C. J. Iremonger, L. Kemp, C. van Schaik, and H. Murray. 2001. “Sustainable Farming Systems: Demonstrating Environmental and
Economic Performance.” A Minnesota Institute for Sustainable Agriculture publication. University of Minnesota. St. Paul, MN. www.misa.umn.edu
2. Sovell, L.A. B. Vondracek, J. A. Frost and K. G. Mumford. 2000. “Impacts of Rotational Grazing and Riparian Buffers on Physicochemical and
Biological Characteristics of Southeastern Minnesota, USA, Streams.” Journal of Environmental Management. 26(6): 629-641.
3. J. Reid. 2001. “Phosphorus Risk Reduction: Part 2 of 2.” Cornell Cooperative Extension, Cornell University. www.cce.cornell.edu/yates/
AgCorner4.4.01.htm
4. Boody, G. and M. Krinke. 2001. “The Multiple Benefits of Agriculture: An Economic, Environmental and Social Analysis.” A report from the Multiple Benefits of Agriculture Project, Land Stewardship Project, White Bear Lake, MN. http://www.landstewardshipproject.org/programs_mba.html
| Attachment | Size |
|---|---|
| Benefits of Pasture Based Farming.pdf | 57.7 KB |
