Tyler Chalfant | October 17th, 2019
Iowa farmers are implementing practices to increase sustainability and reduce environmental threats to public health, including crop rotation, use of cover crops, eliminating pesticides, and using alternatives to chemical weeding. One group called Practical Farmers of Iowa organized a series of educational field days over the summer, providing opportunities across the state for farmers to share and discuss these practices. One of the environmental threats in the state comes from nutrient runoff from agricultural fertilizers, which recently have contributed to the growth of toxic microcystins in some Iowa bodies of water, making sustainable farming not just an environmental issue, but a public health concern as well.
Research published last month from Iowa State University scientists found that the widely-used practice of crop rotation helps to reduce pollution, but also depletes organic matter in soil over time. Rotating between corn and soybeans requires less nitrogen fertilizer than continuous corn production, as soybeans leave behind a nitrogen-rich residue in the soil. This allows farmers to save on costs and reduce nitrogen runoff into freshwater lakes and streams. However the abundance of nitrogen contributes to the growth of microbes which, on years when corn is planted, consume nutrients needed for corn production, depleting this organic material in the long run.