Leopold Center for Sustainable Agriculture

A little prairie goes a long way for Iowa agriculture

Back to Leopold Letter Fall 2011

By MELISSA LAMBERTON, Communications research assistant

On experimental cropland at the Neal Smith National Wildlife Refuge, a blaze of color marks patches where native wildflowers bloom. These narrow strips of tallgrass prairie aren’t there for show—they’re a long-term investment in the health and resiliency of Iowa agriculture. Research that began with the Leopold Center and U.S. Forest Service suggests that prairie conservation strips can offer vital environmental services on Midwest farms without compromising the benefits of row-crop farming.

Science-based Trials of Rowcrops Integrated with Prairies, or STRIPs, refers to the multidisciplinary research project team that aims to foster collaboration among farmers, conservationists, policymakers and scientists based on the premise that profitable agriculture and environmental stewardship can coexist. The team held a field day on September 6 and a stakeholder meeting on June 21 to discuss the project’s preliminary findings. 

“We can strategically place perennial vegetation to provide disproportionate conservation benefits,” said Matt Liebman, team member and agronomy professor at Iowa State University. “A small change gives a large effect.”

Historically, prairies dominated Iowa’s landscape, creating the rich soils needed for productive agriculture. Now less than 0.1 percent of Iowa’s prairies remain. By restoring some of those deep-reaching perennial roots to row-cropped fields, farmers and landowners can reduce erosion and nutrient loss, keep waterways free of agricultural runoff and improve biodiversity.

In July 2007, guided by team leaders Matt Helmers, associate professor in ISU’s Department of Agricultural and Biosystems Engineering, and Heidi Asbjornsen, now an associate professor at the University of New Hampshire, researchers established a variety of treatments on 14 watersheds at the Neal Smith National Wildlife Refuge in Jasper County. Treatments range from conventional agriculture to reconstructed prairie to mixed systems with strategically placed perennial strips covering 10 or 20 percent of the watershed. Flumes at the toe of each watershed collect runoff for sampling.

Recent wet years have given the researchers opportunities to see prairie strips at work during high rainfall events. Unlike cool-season grasses which tend to lay flat under heavy rain, native prairie plants like Indiangrass, big bluestem and switchgrass have stiff, upright stems that resist water movement and trap sediment. In watersheds with 10-20 percent prairie strips in no-till cropland, sediment loss was reduced by more than 90 percent. Nitrate and phosphorus movement also decreased.

Small patches of prairie also offer significant havens for biodiversity. Researchers track the abundance of plants, birds and insects on the experimental watersheds, and have discovered species of concern such as field sparrows, dickcissels and eastern meadowlarks feeding and nesting in the prairie strips. Prairies also create year-round habitat and food for beneficial insects that prey on crop pests and pollinate flowers.

Prairie conservation strips can provide greater environmental benefits when paired with other conservation practices, like minimum or no tillage, researchers suggest. Landowners also can manage their prairies for specific purposes, such as grazing, haying, hunting or bird-watching. The Conservation Reserve Program, the Wildlife Habitat Incentives Program, and the Environmental Quality Incentive Program offer technical assistance and financial incentives for establishing prairies which can help offset costs.

The Leopold Center has developed a new four-page fact sheet, A Landowner’s Guide to Prairie Conservation Strips, to help interested farmers get started. You can download the publication from our website or request a printed copy from the Leopold Center.

The STRIPs project is made possible through cooperation of the Neal Smith National Wildlife Refuge and the U.S. Fish and Wildlife Service, with support from the Leopold Center, Iowa Department of Agriculture and Land Stewardship, USDA National Institute for Food and Agriculture, U.S. Forest Service, ISU College of Agriculture and Life Sciences and USDA North Central Region SARE program.

Back to Leopold Letter Fall 2011