By Keith Schneider
Two facts about Michigan agriculture are scarcely recognized outside the fences and beyond the drainage ditches of the state’s 45,000 farms. The first: farming is among the most technologically sophisticated industrial sectors in Michigan and every other state. Second: livestock farms are the state’s largest source of water pollution from toxic nitrates and phosphorus, and air pollution from methane, a powerful climate change gas.
Here on Michigan State University’s 1,100-acre livestock research farm, technology and pollution prevention have converged in a $19.2 million project that has national implications. The goal: prove the value of advanced cattle production practices to stem environmental damage while simultaneously enhancing farm financial statements.
The five-year, multi-state project, which launched in 2021, is led at Michigan State University by Jason Rowntree, professor of animal science and the C.S. Mott Endowed Chair of Sustainable Agriculture. Rowntree has devoted his career to studying how rotational grazing systems that move cattle from pasture to pasture reap benefits for water, air, soil, and climate that have largely eluded mainstream agriculture.
“I start with this premise,” Rowntree said in an interview. “Here are the outcomes we need. We want organic matter to improve soil health and build carbon. We want to improve water infiltration to reduce erosion. The rain you get is the rain you keep. We want to increase ground cover. We want to enhance biodiversity.”
All worthy outcomes, but how will livestock producers know if they are being achieved? That’s the gap that Rowntree and his collaborators have identified and are working to fill.
“There really isn’t anything in place that quantifies the outcomes of these implementations,” Rowntree continued. “Not until we can more aptly quantify these outcomes in water, carbon, biodiversity, soil health, and do that on a watershed and state scale, are we going to get our arms around this. That’s the crux of the research here.”
Cattle and Grass
Rowntree’s laboratory spans 570 acres of fenced pastures where a herd of Fido Red Angus cows and calves, a hearty grazing breed from Montana, feed on abundant stands of tall grass. In the last 15 years, Rowntree has turned the MSU farm into a nationally prominent center of environmentally sensitive livestock production practices that also reduce costs and improve farm profitability.
His work has been methodical. When he first arrived at MSU in 2009, Rowntree halted the use of chemical fertilizers and relied instead on manure and nitrogen-fixing legumes -- clove and alfalfa -- to supply nutrients to pastures thick with tall grass. He and his colleagues build paddocks and move the herd from one to another, essentially mimicking the behavior of American bison or African wildebeest.
The practice allows grasses to grow in abundance and sink deep roots. Keeping the land covered instead of overgrazed allows rain to seep deeper, reduces erosion, and adds organic matter that improves the health and carbon-storing potential of growing plants and soil. Grazing cattle drop fertilizing manure across a pasture, limiting the flow of nitrates and phosphorus into water.
Rowntree installed all manner of monitoring and sampling devices to measure changes in ecological performance over time. The instruments monitor organic matter in soil, water quality, grass growth, and the health and development of the animals. He documents costs and measures the efficiency of rotational grazing, arguing that the technique improves farm profitability.
As causes and solutions to climate change have climbed to the top of public priorities in recent years, Rowntree has also set out to prove that rotational grazing enhances carbon storage in growing plants and in soil. As part of the new project, Rowntree turned to earth science sensing instruments and drones linked to orbiting satellites. The equipment measures wind speeds, concentrations of atmospheric carbon dioxide, water vapor, temperature, and pressure in order to calculate the amount of carbon dioxide and water moving from the atmosphere into the soil and from the soil into the atmosphere.
The data is meant to test Rowntree’s thesis that grazing cattle in rotational systems stores more carbon than it releases, improves water quality and supply, and can be part of the solution to our warming Earth.
Big Challenge
Cattle production is particularly damaging to land, water and climate. Big conventional cattle feedlots are major sources of pollution almost everywhere they are located, according to state environment departments. The World Resources Institute, a respected Washington-based environmental think tank, found that cattle, dairy cows, and other livestock are responsible for over 30 percent of global methane emissions -- a greenhouse gas that has global warming potential 80 times higher than that of carbon dioxide over a 20-year period.
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