2017: Iowa Corn Belt

On June 26, a diverse group of companies with an interest in the long-term resilience of U.S. corn and soy production journeyed together to hear the latest science and see first hand from farmers where the opportunities and challenges lie. Our shared goal is to maintain and improve soils and productivity as new knowledge is gained about how to do so through cover crops, extended rotation, and edge of field practices, such as grassed waterways and bioreactors.

We spent the morning with Dr. Matt Liebman and Dr. Mike Castellano at the ISU research farm, seeing the results of long-term trials. The Marsden Farm Trials compare three systems: a 2-year corn/soybean rotation, a 3-year corn/soybean/oat + red clover rotation, and a 4-year corn/soybean/oat + alfalfa/alfalfa rotation.

For many of us it was surprising when Dr. Castellano shared that fertilizer is not the problem when it comes to water quality issues in the corn belt when farmers use practices that keep living roots in the ground year round, such as cover crops and extended rotation with small grains. The cover crops keep the ground full of living roots that take up and hold Nitrogen in place so that it can’t be washed into the water table. The Marsden trial reveals that “diversification of conventional corn soybean systems with small grains and forage legumes can allow for large reductions in the use of mineral fertilizers and herbicides and lead to less environmental damage, equivalent profitability, improved soil quality, and higher crop productivity.”

Read Liebman’s paper on the Marsden Farm Experiment and the data on farm economics and environmental impact. data on farm economics and environmental impact.

Details on the water quality and GHG benefits of these practices using data from the Iowa Nutrient Reduction Strategy and the Fieldprint Calculator can be found here.

About the Corn Farms

Following the ISU research trials we visited Jeremy Gustafson’s farm, where we heard from Jeremy about the risks farmers face for adopting cover crops and rotating with a small grain (in this case oats). Jeremy outlined the recipe for giving farmers like him the confidence to experiment with cover crops and extended rotation and listed the barriers:

  • Cost-share per acre of cover crops or small grain
  • Make it easy to get cover crop seed and support by:
    • Coordinating groups of farmers around aerial seeding of cover crops in the fall
    • Purchasing cover crop seed from input suppliers
  • Pay farmers to mentor other farmers and encourage knowledge share and support in expert facilitated farmer network groups (i.e. PFI)
  • Create market pull for small grains as inclusion in a sustainable feed ration

Jeremy Gustafson’s Farm

At Jeremy’s farm we also had an opportunity to view the rainfall simulator with NRCS representative Neil Sass. The rainfall simulator visually represents the differences in water runoff and soil erosion between different types of tillage systems with and without cover crops or an extended rotation with a small grain.

In the afternoon groups split and visited three other farms.

Sutter Farm – Kenny, Jacob, and Tyler Sutter

Sutter Farms encompasses 3,300-3,500 acres on which they raise beef, hogs, corn, soybeans, wheat and oats. Four complete families from four generations depend on the farm for their livelihood. They participate in the Unilever Sustainable Soy program practicing no-till and minimum-till to prevent soil erosion. The Sutters use cover crops in the winter, including cereal rye, to help retain soil moisture, prevent erosion, and store nutrients for the next season. Grazing the cover crops with their cow/calf herd provides an important source of winter feed and the soybeans and corn they grow goes into the processing plant that creates the feed for their hogs.  He wants to start using red and sweet clover as a cover crop instead of straight cereal rye, but requires more short-season crops like small grains to do so. Kenny has set up test strips of cover crop experiments to evaluate different cover crop management strategies side by side such as grazing, mowing, and harvesting cover crops for seed.

Cardinal Farms – Craig Fleishman and Dan Taylor

Craig and Deb Fleishman raises corn, soybeans and oats on their century farm. Conservation and profitability drives his farm decision making, and he’s looked to come to a balance between the two. He’s been ridge-tilling since 1981, which allows him to combine cultivation and herbicides in a system that reduces both tillage and chemical use. Over the last few years, he’s included oats into the rotation on some of his corn and soybean ground. He’s also maintained a demonstration of a three-year crop rotation in strips on one of his fields.

Dan and Ila Taylor are neighbors of Craig’s and works with Craig on the oat harvest. Dan and Ila raise and finish cows and hogs for Niman Ranch and have converted about 100 acres of their land from row crops to grass or hay for the livestock. Using cover crops expands their grazing season by almost three months and offers a tangible economic benefit to the operation.

Helland Farms – Mike Helland and Lee Tesdell

About 60% of the farmland in Iowa is rented and farmed by non-owner operators. If the operators and the owners are not on the same page in terms of farming practices and outcomes it can be difficult for a farmer to invest in soil health practices that protect the land asset. Mike and Lee are an example of a land owner (Lee) cooperating with a farm operator (Mike) to achieve soil health and conservation outcomes. Together they apply for cost share programs through NRCS and split the costs on investments like cover crops or new technologies.

Sediment and nutrients in water drainage is a critical issue in Iowa and Mike and Lee work together to address water quality issues on this land. Lee installed capital intensive solutions like a saturated buffer system and a wood chip bio reactor. Mike, for his part, uses cropping system management by no-tilling beans for 23 years and one-tills his corn. Mike integrates livestock on the farm, last year he raised 500 acres of cereal rye for pasture and hay for cattle.

Key Takeaways

On Wednesday, following the field visits, the group extracted observations about qualities of leadership, sustainability, and systems change from our tours.

A shared systems perspective was developed and is captured below:

Why soil health is important:

  • Increases in soil organic matter (SOM) result in reduced GHG emissions, decreased soil erosion, and improved water quality.
  • Healthy soil holds moisture in the ground to make water more available during drought years and reduces flooding in wet years.
  • Healthy soil reduces disease and plant stress, and decreases the need for inputs such as synthetic fertilizer and herbicides.
  • Therefore, healthy soils create the conditions for a more resilient production and secure supply in the long term

What practices contribute to health soil:

  • Continuous cover (living or residues) on the ground for as much of the year as possible (cover crops, rotations);
  • Minimal soil disturbance (reduced tillage, no till);
  • Diversity (cover crops, rotations);
  • Organic compost or manure inputs when possible (integrated livestock systems, rotations and cover crops enable this system either in cooperation with neighbors or on own farm).


  • Most benefits are long-term, but there are short-term costs, and it’s not clear who will pay.
  • There is limited market and little infrastructure for rotation crops like small grans and hay.
  • Farmers are ostracized by their neighbors when they try something different.
  • Over 60% of the land in Iowa is rented, forcing farmers into short term agreements that do not incentivize long term investment in soil health.
  • Cover crop seed, advice, and infrastructure is not readily available from Ag Retailors and other traditional sources of inputs for farmers

What’s needed to overcome difficulties:

  • Market pull for small grains
    • Feeding small grains as part of a sustainable feed ration
    • An early mover to prime the pump and increase supply
  • Incentives for cover crops,
  • Facilitated farmer learning groups and paid farmer mentors to increase social acceptance and knowledge network of cover crops, rotation, and use of livestock in the system

Therefore, we’re in a redesign mode, rather than a tweaking mode, which requires not only technical but also organizational and leadership changes.

Key leverage points for future action:

  • Pre-competitive commitment to increase small grains in feed rations
  • Develop good storytelling and soil health education for companies that have close relationships with farmers, and for land owners who are renting farmland.
  • Convene ag retailers to be more supportive of cover crops and diverse rotations by making it easier to get seeds and access to the right equipment and infrastructure
  • Amplify the PFI model to support farmer-to-farmer knowledge exchange and peer mentoring
  • Collaborate to insure that markets are available for more diverse rotations
  • Work with R&D teams to develop new products that include small grains and other crops needed to make corn and soybeans more sustainable
  • Joint advocacy to reform crop insurance

Sustainable Food Lab will support a working group on small grains as part of a sustainable feed ration moving forward. We will also be facilitating an online discussion through Climate Collaborative implementing regenerative agriculture in the supply chain.

If you are interested in participating in one of these working group please email Elizabeth Reaves at [email protected].

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