“Long Rotations Leave Too Much on the Table!” Really?

Buz Kloot, Ph.D.
Jul 28
3 min read

Over the past few weeks, the tillage and no-till debate has sparked surprising and passionate discussion among our readers. We've responded with a series of blogs diving into the science, farmer experience, and stewardship questions at stake [1–5]. As part of this effort, we're highlighting two key South Dakota studies, both based at the Brookings research station, that offer important, complementary insights into why longer crop rotations can make not just agronomic but economic sense.

Two Complementary Studies, One Big Takeaway

Recent peer-reviewed work by Bansal et al. [6] and Feng et al. [7] compared long-term no-till systems: continuous corn, corn–soybean (CS), and diversified four-year rotations with small grains, peas, and sunflowers.

While they explore similar themes, the two papers differ in focus and together provide a fuller picture:

Bansal et al. (2024) focus on yield and profit comparisons, showing corn yields up to 89% higher after peas vs. continuous corn, soybean yields ~38% higher after wheat, and net revenues holding steady or improving in diverse systems. They emphasize reduced nitrogen and seed costs as profit drivers.
Feng et al. (2021) zoom out to a systems-level view, examining not only profits but economic resilience over time, especially under limited fertilizer or weather stress. They show diversified systems buffer farms against risk and input price swings, offering stability beyond just yield numbers.

Why It Matters for South Dakota Farmers

Both studies agree: longer rotations offer more than agronomic perks—they bring real economic advantages. While small grains or peas may have lower per-acre market value, they improve soil health, lower input needs, and set up following crops for success. Diversified systems also weather market and environmental ups and downs better—critical for long-term profitability.

A Personal Note

In an interview I did with Dr. Dwayne Beck at Dakota Lakes Research Farm back in October 2013—as the Atlas storm rolled into South Dakota—he summed it up simply: "Corn is a good thing. We can keep a high percentage of corn in the rotation. But we're throwing this other stuff in there just to mix it up, and it makes the corn better and much cheaper to grow." Beck has long emphasized that diversity gives economic advantages you don’t always see on paper—until you experience the system yourself. To us, these new Brookings studies beautifully corroborate what Beck was saying more than a decade ago.

Other Resources

We also reviewed summaries from USDA-ARS and SDSU Extension [8,9]. These provide useful overviews, and we hope our blog helps whet readers' appetites to explore the full research landscape even further.

Our Take

For producers wondering if it’s worth expanding beyond corn and soy: the evidence says yes. The challenge ahead is translating these findings into practical, region-specific tools that help farmers on the ground.

If you think we should dive even deeper into the literature or explore additional questions, let us know—we welcome your input!