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Study shows crop rotation with alfalfa improves corn, soy yields

Wisconsin farmers are learning about a long-term study into corn and soybean yields using different crop rotation schemes. 

University of Wisconsin agronomy professor Joe Lauer says their research shows higher corn yields after alfalfa. “During that time, you can get much better, longer-lasting, if you will, root channels for example. You can get better soil aggregation.”

And, he says that one year of soybeans will yield between three and five percent more.

Lauer’s theory of the perfect crop rotation is two years of corn followed by one year of soybeans and then two or three years of alfalfa. He says, “For the first year of corn following alfalfa, you don’t need to apply any nitrogen. The second year of corn, you would need to apply probably about a half rate, but then when you grow soybeans, you really don’t have any fertility that goes on so the only input that you’ve got is about a half a rate of nitrogen in that second year of corn.” That is something Lauer would like to study further, but he says it takes a long time to get this kind of data, since a five year crop rotation takes four years of set-up before researchers can collect information.

And he says always monitor phosphorus and potassium.

Lauer spoke to Brownfield at the Wisconsin Agribusiness Association’s Agribusiness Classic in Madison, Wisconsin.

Listen to Joe Lauer speak with Brownfield’s Larry Lee here: