Iowa State University Research Farms Utilize Conservation Practices for Science, Stewardship

Iowa State University’s 13 Research and Demonstration Farms around the state have served for decades as models of agricultural and scientific progress for Iowa’s farmers and landowners.

The same holds true for the goals of Iowa’s Nutrient Reduction Strategy.

For years the university’s agricultural researchers have used the farms to study and demonstrate the effects of conservation practices to preserve water quality, keep soils productive and improve the environment. The work has been conducted on acres devoted to research and those not currently in research plots but devoted to producing crops or sustaining livestock.

The ISU research farms strive to serve as models of stewardship by implementing practices on fields, field edges and streamside borders. By practicing what they preach, these farms inspire visitors to do the same.

Matt Schnabel, the superintendent at ISU’s Northern Research Farm near Kanawha, said the farm serves as a model for neighboring farmers.

Cover crops

“The majority of our fields without trials are planted with cover crops. We also have planted milkweed for monarch butterfly conservation and for pollinator habitat,” said Schnabel, a 2010 graduate of ISU in agricultural systems technology. “All these practices add benefits to the land, environment and cropping system. Installing and utilizing these practices on our research farm allows farmers to see things first-hand before implementing on their own farms. We act as a guinea pig and show them what they can do on their land.”

Schnabel said he’d like to put more acres into habitat, reduced tillage, and add saturated buffers. Saturated buffers reduce the movement of nutrients by diverting a portion of tile flow into shallow groundwater. This raises the water table of the buffer and allows organic matter to remove nitrate before the water enters an adjacent stream.

Cover crops are one practice outlined in the Nutrient Reduction Strategy to reduce nitrate leaching from fields. Additionally, cover crops are beneficial to agricultural systems by increasing soil organic matter. Ames-area ISU farms have been using oats, radishes or winter rye as cover crops.

Tim Goode, manager for ISU Research and Demonstration Farms and the Committee for Agricultural Development, a nonprofit affiliated university organization, said that in the last year 800 acres of cover crops were planted on research farms and other acres of cropland. Besides cover crops, the research farms use an array of 18 other nutrient management practices from the strategy, including wetlands, extended rotations and runoff retention.

“The research farms use a broad range of nutrient management practices,” Goode said. “In the Nutrient Reduction Strategy, the Iowa State-led science assessment team lists many research-proven practices to reduce nitrogen and phosphorous losses. Each of these practices have been studied and then implemented multiple times on ISU-managed farmland, either in the Ames area or on farms around the state.”

Long-term projects at the Northeast research farm

The ISU research farm near Nashua celebrated its 40th anniversary last year and has been a long-term example of water quality and conservation success, thanks to a university, local group and agribusiness partnership. The Nashua research farm has been the site of dozens water quality research projects and many field days to show off the results.

The Nashua farm has implemented and maintained many conservation practices, including cover crops, buffers and bioreactors. Its water quality plots — each drained by a separate tile drainage line in a long-term monitoring project — was initiated in 1988, with funding from the Leopold Center for Sustainable Agriculture in the College of Agriculture and Life Sciences.

The farm also installed an early version of a bioreactor, an edge-of-field conservation practice that removes tile flow nitrates by way of denitrification through a woodchip basin underground. The next generation of bioreactor research is closer to campus near Boone at the Agricultural Engineering/Agronomy Research Farm. At this site, scientists monitor nine experimental bioreactors which are being tested for various tile drainage volumes and fill materials with funding provided by the Iowa Nutrient Research Center.

In the coming year, the next installation of water quality projects will be completed by ISU partnering with Committee for Agricultural Development, USDA Natural Resources Conservation Service, Big Creek Watershed Protection Project and the Boone County Soil and Water Conservation District on a university-managed farm near Madrid. At this location, a series of three conservation practices will be installed to reduce the nutrient load entering Big Creek:  saturated buffers, an oxbow wetland and a double-barreled bioreactor. Each of these conservation practices has been outlined in the strategy as effective edge-of-field nutrient management tools.

“Many research and educational needs, demands, uses and decisions impact how ISU-managed land is used annually. But overall, ISU is strongly committed to managing farmland and implementing practices in a manner that supports land stewardship over the long term,” Goode said.

The Iowa Nutrient Reduction Strategy is a science and technology-based framework to assess and reduce nutrients to Iowa waters and the Gulf of Mexico. It is designed to direct efforts to reduce nutrients in surface water from both point and nonpoint sources in a scientific, reasonable and cost effective manner.

Conservation/Nutrient Management Practices by farm

Agricultural Engineering/Agronomy Research Farm near Boone

• Wetlands
• Buffers
• Runoff retention
• Oat and winter rye cover crops
• Perennial energy crops
• Strip tillage
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Extended rotations with alfalfa
• Managed timing and rates of N fertilizer
• N fertilizer inhibitor

Allee Memorial Research and Demonstration Farm near Newell

• Winter rye cover crops
• Perennial energy crops
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer
• N fertilizer inhibitor

Armstrong Memorial Research and Demonstration Farm near Lewis

• Wetlands
• Winter rye cover crops
• Buffers
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Extended rotations with alfalfa
• Managed timing and rates of N fertilizer

Central Iowa Research and Demonstration Farms near Ames

• Wetlands
• Bioreactor
• Oat and radish cover crops
• Buffers
• Perennial energy crops
• Strip tillage
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Extended rotations with alfalfa
• Managed timing and rates of N fertilizer

Horticulture Research Station near Ames

• Winter rye cover crop
• Terraces
• Runoff retention
• Perennial crops
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation

McNay Memorial Research and Demonstration Farm near Chariton

• Oat and winter rye cover crops
• Extended rotation of alfalfa
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Extended rotations with grass and alfalfa
• Managed timing and rates of N fertilizer

Muscatine Island Research and Demonstration Farm near Fruitland

• Winter rye cover crops
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer
• Strip tillage

Neely-Kinyon Memorial Research and Demonstration Farm near Greenfield

• Winter rye cover crops
• Buffers
• Extended rotations with alfalfa
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer

Northeast Research and Demonstration Farm near Nashua

• Bioreactors
• Winter rye cover crops
• Buffers
• Extended rotations with alfalfa
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer
• Strip tillage

Northern Research and Demonstration Farm near Kanawha

• Extended rotations with alfalfa
• Oat and winter rye cover crops
• Buffers
• Strip Tillage
• Controlled drainage
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer

Northwest Research and Demonstration Farm near Sutherland

• Winter rye cover crops
• Buffers
• Extended rotations with alfalfa
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer

Southeast Research and Demonstration Farm near Crawfordsville

• Buffers
• Extended rotation of alfalfa
• Strip Tillage
• Wetlands
• Controlled drainage
• Extended rotations with alfalfa
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer
• Perennial energy crops

Western Research and Demonstration Farm near Castana

• Buffers
• Terraces
• Runoff retention
• Winter rye cover crops
• Extended rotations with alfalfa
• Fertilizer rates based on soil testing
• Phosphorus fertilizer and manure incorporation
• Managed timing and rates of N fertilizer