September 26, 2005
A team of Iowa State University animal scientists is evaluating how to improve the water quality of Iowa's farm streams through livestock grazing practices.
Jim Russell, animal science professor, and his team are trying to determine how cattle grazing management practices may reduce phosphorus and sediment levels in pasture creeks. Seventy-five people attended a field day at the ISU Rhodes Farm in Marshall County in September to learn more about the team's findings.
It is common for Iowa beef producers to use the land near creeks for grazing cattle because it offers water access and shade, but Russell notes that some producers overgraze their pastures, which may lead to increased soil erosion. Russell's team is comparing the effects of several management practices on stream bank erosion including continuous grazing, rotational grazing and controlling animals' access to streams.
The research is aimed at offering alternatives to help beef producers stay within total maximum daily loads (TMDL) water quality standards as set by the U.S. Environmental Protection Agency. Although adhering to TMDL levels is currently voluntary, the Iowa Department of Natural Resources and the Leopold Center for Sustainable Agriculture at Iowa State are funding Russell's research to find ways to decrease non-point source pollution and create effective grazing systems.
Russell also is comparing the cost of piped-in water sources to the cost of riverbed crossings for cattle and equipment. His team is monitoring the movements, manure distribution and grazing habits of 90 fall calving beef cows in the pastures.
The research is in its initial stage and Russell expects it will take several grazing seasons before his team can measure significant differences.