How Diversified Farming Systems Can Help Farmers While Protecting Soil and Preventing Pollution

The document argues that replacing a portion of Midwest corn and soybean acreage with diverse crop rotations—including oats and alfalfa—can increase yields and maintain profits while significantly reducing soil erosion, chemical runoff, and greenhouse gas emissions. Based on Iowa State University research and Union of Concerned Scientists modeling, the report suggests that such systems could be scaled to 20-40% of Iowa's farmland, potentially saving taxpayers hundreds of millions of dollars in water cleanup costs. However, adoption is hindered by market, financial, and technical barriers, necessitating federal policy reforms in crop insurance, USDA loan funding, and agricultural research.

• Diversified crop rotations involving three or four crops can increase yields and maintain per-acre profits compared to the standard two-crop corn-soybean system. Specifically, average corn yields increased by 2 to 4 percent and soybean yields by 10 to 17 percent.
• Diverse rotations significantly reduce the use and runoff of agricultural chemicals, with herbicide use dropping by 25 to 51 percent and herbicide runoff in water decreasing by 81 to 96 percent. Nitrogen fertilizer application rates were reduced by 43 to 57 percent.
• Implementing diverse rotations without tillage in the 25 most erodible Iowa counties (15% of state cropland) would reduce soil erosion by 91% and save taxpayers and downstream communities between $196 million and $198 million annually in surface water cleanup costs.
• Economic modeling indicates that diverse crop rotations could be adopted on 20 to 40 percent of Iowa's farmland (5 million to 11 million acres) without price changes forcing a return to corn-soy. This scale of adoption would provide total annual environmental benefits of $235 million to $505 million.
• The dominant two-crop system contributes to significant environmental damage, including the Gulf of Mexico "dead zone" and climate change, with nitrous oxide emissions from agricultural soil management accounting for 5 percent of the US share of heat-trapping gases.
• Farmers face several barriers to adopting diversified systems, including underdeveloped markets for small grains, high up-front equipment costs, short-term land leases, and a lack of technical guidance due to declining numbers of county-level agricultural extension agents.

APA

Mulik, K. (2017). How Diversified Farming Systems Can Help Farmers While Protecting Soil and Preventing Pollution. Union of Concerned Scientists. https://www.ucs.org/sites/default/files/attach/2017/05/rotating-crops-summary-ucs-2017.pdf

Chicago

Mulik, Kranti. How Diversified Farming Systems Can Help Farmers While Protecting Soil and Preventing Pollution. Union of Concerned Scientists, 2017. https://www.ucs.org/sites/default/files/attach/2017/05/rotating-crops-summary-ucs-2017.pdf.

Wikipedia

{{cite report |last1=Mulik |first1=Kranti |title=How Diversified Farming Systems Can Help Farmers While Protecting Soil and Preventing Pollution |publisher=Union of Concerned Scientists |date=May 2017 |url=https://www.ucs.org/sites/default/files/attach/2017/05/rotating-crops-summary-ucs-2017.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{mulik2017how, author = {Mulik, Kranti}, title = {{How Diversified Farming Systems Can Help Farmers While Protecting Soil and Preventing Pollution}}, institution = {Union of Concerned Scientists}, year = {2017}, month = may, url = {https://www.ucs.org/sites/default/files/attach/2017/05/rotating-crops-summary-ucs-2017.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }