The Iowa State University STRIPS project — Science-based Trials of Row-crops Integrated with Prairie Strips — started out as an idea in 2007 and has grown into a resource, supporting on-farm implementation of prairie strips across the Midwest.
The primary goals of the STRIPS project were to evaluate the impact of planting native perennial grasses and forbs (generally non-grass or woody vegetation) within and along the edges of the row crop fields in Iowa.
The project began at the Neal Smith National Wildlife Refuge near Prairie City in central Iowa, and the positive results from that site helped researchers evaluate and fine-tune prairie strip applications to move to a much broader scale.
Iowa Learning Farms produced a webinar and virtual field day with the STRIPS group in July to help raise awareness of how prairie strips can contribute to a comprehensive conservation plan for working farms. Prairie strips are one of several strategies included in the ILF Whole Farm Conservation Best Practices Manual, which is available from the ISU Extension Store.
Omar de Kok-Mercado, STRIPS project coordinator, provided some background on the STRIPS project and recent achievements.
“Since our first collaborating farmer started on-farm prairie strips in 2014, we’ve continually expanded to our current count of 66 collaborators across Iowa, with 600 acres of prairie strips protecting some 5,500 acres of crop land,” de Kok-Mercado said. “These numbers represent the acres of farms STRIPS and partners are working with directly, but it’s starting to get harder to keep track as we’re seeing widespread adoption in the Midwest.”
BUILDING SOIL: Prairie strips can be planted on low-yielding areas of cropland, or alongside waterways, on end rows or in drainage areas.
Beyond Iowa, the STRIPS project has grown to include 13 additional states, with prairie strip acres now exceeding 11,000 acres, protecting roughly 110,000 acres of cropland.
Prairie strips and CRP
The STRIPS team assisted USDA in creating a new Conservation Reserve Program practice that went into effect in December. Application details are available through USDA service centers. “We worked directly with USDA to formulate the policy for implementing prairie strips under the CRP umbrella,” de Kok-Mercado said. “It is quite exciting to be part of nationalizing the opportunity to adopt prairie strips.”
Farmers and landowners can sign up prairie strips under CRP and get cost-share and an annual rental payment to establish and maintain the practice.
What are benefits?
Most of Iowa was once covered in prairie for some 10,000 years. The first farmers to bust through the sod and encounter the rich black soil knew they had struck gold. Modern farming techniques continued to improve and expand over time, eliminating most of the natural prairie and laying the earth bare to wind and water, resulting in soil losses through erosion. In recent decades, substantial effort has gone into mitigating these losses, and a return to prairie is one practice showing promise.
Scientists working with prairie strips have found integrating a small percentage of prairie into row crops yields disproportionate benefits to soil and water quality and native plants, insects and birds. As an added benefit, economic analysis shows that prairie conservation strips are one of the most affordable conservation practices available to farm landowners.
During his July 29 Virtual Field Day presentation, Tim Youngquist, ISU STRIPS farmer liaison, presented some facts and figures from the first 10 years of the project. When adding 10% prairie to no-till corn and soybean fields, these reductions took place:
- 37% in water runoff
- 95% in sediment loss
- 77% in phosphorus runoff
- 70% in nitrogen runoff
- 70% in subsurface nitrate-N concentrations (untiled)
One of the first STRIPS collaborating farmers, Gary Guthrie in Story County, was a guest speaker in the virtual field day and reflected on some of the more tangible environmental benefits he’s noticed with prairie strips.
“I established a half-acre prairie behind my house,” Guthrie said. “One September, I was stunned by the sound of the bees and insects working all those gorgeous flowers. I was struck by how a small part of the farm could make such a difference.”
Guthrie reported that ISU researchers had identified 29 native bee species in his strips. In addition, the variety and quantity of birds has been tremendous. “They’ve even observed Upland Sandpipers, which aren’t commonly found in Iowa, but seem to be drawn to the strips as a preferred habitat.”
A perfect prairie strip site?
“One of the advantages of prairie strips is that Iowa was once roughly 85% prairie, so the strips should work just about anywhere,” de Kok-Mercado said. “Every field and landscape has its own unique characteristics so there is no-one-size-fits-all solution. Farmers can now work with USDA’s Natural Resource Conservation Service to determine what layout will work best to meet the objectives for their farm.”
Typically, an NRCS technician will do a site survey, work with the farmer to create a plan, then design and engineer a solution for the farm. The final plan would include location, size, site preparation, recommendations on seed mix, and advice for getting the strips established and flourishing. Farmers can choose to contract the implementation work or do it themselves. NRCS provides resources and information and can assist with the CRP process.
Youngquist offered additional guidance during the webinar and field day programs. Some key planning concepts include:
- fall planting better to establish flowering perennials (forbs)
- initiating after soybeans found more successful
- higher grass density better for weed suppression
When planning the layout, space the strips at uniform distances to facilitate operation of planting and harvesting equipment. Use the strip areas for turnarounds. Consider planting strips in underperforming parts of a field. And if practical, plant short row and oddly shaped field areas with prairie.
Also, in pasture, existing vegetation should be sprayed out multiple times, and if practical wait for a full season before initiating the strip.
What’s next from STRIPS?
Current research from STRIPS includes assessments of direct cost and yield to determine a financial correlation between strips and productivity, a study looking at the influence of additional perennial and native plants on honeybee populations, a project evaluating the efficacy of nitrate absorption and removal by prairie strips to reduce nitrate loss to groundwater and waterways, and a look at the ability of prairie strips to mitigate antimicrobial-resistant gene transfer.
GAINING TRACTION: A new conservation practice, planting prairie strips into fields is becoming increasingly popular to increase productivity of land.
“STRIPS is also taking a closer look at long-term prairie strip rotations with respect to spatial and temporal impacts,” de Kok-Mercado said. “We’re curious what role prairie strips can play in regenerating degraded soils. What effects, if any, does rotating prairie strips across a landscape have? The time scale may be on the order of a decade but incorporating prairie in long-term rotations may offer potential for continual renewal.”
Prairie strips are a proven asset to comprehensive whole-farm conservation practices. These versatile structures deliver short-term benefits to farms, and it appears that researchers are just scratching the surface of potential uses and additional benefits. To learn more about STRIPS, watch the Iowa Learning Farms webinar and virtual field day.
Ripley is an Iowa Learning Farms conservation outreach specialist