Are you doing things the same way this year as you have the past 20 years? Is that just “what works?” Do you stick with what you’ve always known?

If that’s where your cropping system resides, then this may be the year to shake things up a bit. You know that field that has been in continuous corn since you took over the farm from your father? Let’s start there.

Purdue University recently celebrated the 50-year milestone of a long-term crop rotation and tillage study. Tony Vyn, a recently retired agronomy professor at Purdue, took over the study in 1998 and saw it through the end of its 50th year in 2024. He compared results between four different crop rotations and four different tillage systems on a productive dark prairie soil.

The results

Over the course of the study, both corn and soybeans saw yield boosts in systems that rotated multiple crops. For corn, those yield increases took place 48 out of 50 years. And for soybeans, yields increased in 42 out of 50 years. The results were most drastic for no-till tillage systems.

“No-till had the biggest response to rotation of corn/soybeans versus continuous corn,” Vyn says. “Essentially, the no-till rotation response in corn was 18% yield increase, and the moldboard plow rotation response was only 5%.”

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In the new year, do you plan to convert acreage to a no-till system? Is less tillage a goal for your operation? If so, then this study shows you will benefit most from implementing a crop rotation instead of a monoculture cropping system.

Additionally, if you are already rotating your corn and soybeans, then perhaps you cut some tillage this year and see if that continues to boost yields. If chisel plowing is your go-to tillage system, Vyn recommends moving away from it.

“It is the one tillage system that I have the most fear of long term, even though it is a popular thing to do,” Vyn adds. He shares that the soybean yield advantage of 6% to 7% in rotation systems seen in the study is not reflected in chisel plow systems. For example, in the past 10 years, soybean yields after corn were only one bushel per acre higher with the chisel plow system.

What’s next?

On an individual level, it is up to you to do what you wish with this information. This isn’t the time to dive headfirst into a new crop rotation system and tillage system. However, consider small changes that you could implement. Perhaps you have an 80-acre field that has always been in continuous corn. What do you say about switching it to a corn/soybean rotation?

Or maybe you have wanted to pull back on tillage. You could convert a few fields to no-till or strip till and see how yields respond. In fact, in the past 10 years, the biggest yield gains with rotation have been in the fall strip-till system.

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At a broader level, Vyn says that more research still needs to be conducted. He shares that there also needs to be a larger focus on how different soil types respond to the various crop rotation systems.

“I think that rotation experiments need to be continued,” Vyn says. “But we can’t continue them if we’re not 100% devoted to constantly improving the management of those crops or giving consideration to doing rotation experiments with other crop species and sequences on other soils.”

You’ll find that different crop rotation and tillage systems work on different soils across your farms, and I think it would be beneficial to continue this study and broaden the scope to include more variety. For now, however, I think there is a benefit to setting up your own trials to see how a different crop rotation or less tillage could affect your yields.