Uncovering Best Practices for Cover Crops to Optimize Crop Production

By Kaine Korzekwa

Planting cover crops is a beneficial agricultural practice. One of their many benefits is to cover soil for times when farmers cannot plant cash crops like corn and soy—over the winter, for example. But it is not as simple as just growing cover crops in between growing seasons. Farmers have multiple decisions to make about optimizing cover crop production.

Researchers like Heidi Reed at Pennsylvania State University want to help farmers make the best decisions about their cover crops. In a recent study, Reed and her team looked at the impact of cereal rye seeding rate, termination time, and nitrogen rate. The study was published in Agronomy Journal, a publication of the American Society of Agronomy.

The research focused on the effects cover crops have on both soil and soybeans after planting. Their study took place at two sites in Pennsylvania over the course of three years. "This type of applied research is so important because sustainable practices need to work for farmers," Reed explains. "We want these methods to be adopted at a large scale."

The rye seeding rate is the amount of cereal rye seed that is planted in a certain area. The researchers tested three different seeding rates. Similarly, the nitrogen rate is the amount of nitrogen fertilizer applied in each area. They tested two different amounts in the study.

Termination time is more complex. It has to do with when the cover crop is killed to make room for the crop the farmer will grow and sell, which was soybeans in the study. "Preplant-kill" is when the cover crop is killed before soybeans are planted. "Planting green" is when the cover crop is killed after the soybeans are planted. This means the cover crop is green and growing when the soybeans are planted. The researchers were curious about how the termination time would impact soybeans.