Iowa State University a Partner for Cleaner Waters

AMES, Iowa--The harvested Iowa landscape “sea of brown” increasingly is interrupted by fields of green this fall. What may appear from the road to be a field of very late planted and still growing soybeans is instead a field planted in cover crop. More Iowa farmers are planting cover crops late in the growing season, a practice the Iowa Nutrient Reduction Strategy identified as one way to help protect Iowa’s water quality.

“Cover crops reduce soil and nutrient runoff and build soil organic matter,” said Paul Kassel, field agronomist with Iowa State University Extension and Outreach. “Extension and Outreach through Iowa Learning Farms is hosting multiple cover crop field days this fall to increase farmers’ understanding of the costs and benefits of growing cover crops.”

Kassel said extension specialists planned a Nov. 1 field day at test plots in Buena Vista County where a mixture of cereal rye, tillage radishes and turnips demonstrated several cover crop options. The plots were aerially seeded into standing corn and soybeans. The plots are part of the North Raccoon River Watershed project to improve water quality within the watershed.

Additional Iowa Learning Farms cover crop field days are scheduled for

  • Nov. 7 in Amana
  • Nov. 12 in Plainfield
  • Nov. 13 in Postville
  • Nov. 14 in Stanton
  • Nov. 19 in Holland

Learn more about these events at

Kassel said planting cover crops is only one effective nutrient reduction practice that was identified by the science assessments done in conjunction with the development of Iowa’s Nutrient Reduction Strategy.

Iowa’s Nutrient Reduction Strategy

Iowa is one of 12 Mississippi River Basin states called upon to develop a state plan to reduce the nitrogen and phosphorus in surface water leaving the state. The goal is to reduce the nitrogen and phosphorus loadings to the northern Gulf of Mexico by 45 percent. Iowa State University, Iowa Department of Agriculture and Land Stewardship and Iowa Department of Natural Resources worked in partnership to create Iowa’s plan. The Iowa Nutrient Reduction Strategy was released in Nov. 2012, opened to public comment and finalized in May 2013.

“Iowa’s plan is a practice-based approach to reducing the nitrogen and phosphorus impact on water,” said John Lawrence, College of Agriculture and Life Sciences Associate Dean, and Director of Agriculture and Natural Resources Extension and Outreach.  “The plan is voluntary, which means it is not regulated. However – it is not optional. All Iowans can make a difference when it comes to leaving our land and water in better shape for future generations.”

Iowa State University hosts the Iowa Nutrient Reduction Strategy website,, where the plan details are made available. The Iowa strategy is a coordinated approach for reducing nutrient loads discharged from the state’s largest wastewater treatment plants, in combination with targeted practices designed to reduce loads from nonpoint sources such as agriculture.

Lawrence said Iowans are showing great interest and support in the plan. “Success can be achieved using tools known to work, such as targeted, voluntary conservation measures, in conjunction with research, development and demonstration of new approaches. The goal is application of proven practices in fields and cities across Iowa,” he said. “While the focus is on the Gulf, we should keep in mind that there are benefits in Iowa – and they are very real.”

Making a positive impact on water quality

Agricultural practices with the largest potential impact on nitrate-N concentration and phosphorus load reduction are outlined in a publication, Reducing Nutrient Loss: Science Shows What Works, available from Iowa State. It is available for free download at; search for "SP 435." Those practices also are outlined on the website, launched Oct. 28. contains resources to help Iowans protect and improve water quality. The site has “Farm,” “Residential & Urban,” and “City & Industry” sections that provide information about science-based practices that can be implemented to improve water quality. It includes descriptions of water quality practices that can be applied, benefits of the practices and links to additional information.

Iowans also can follow @CleanWaterIowa on Twitter or “like” the page on Facebook to receive updates and other information about the ongoing Iowa water quality initiative.


PHOTO: Radishes as cover crop are growing in Iowa this fall. Photo by Paul Kassel, Iowa State University.