By Daren Mueller, Extension Plant Pathologist

This study, funded by the United Soybean Board (USB), was conducted to understand the potential for cover crops to perform in a corn and soybean rotation, and to collect data on the performance of cover crops in those rotations in relation to the timing of termination.

The research showed winter cereal rye that grew an extra three weeks prior to soybeans produced about 300-400% more biomass (Fig. 1) with a 100% increase in nitrogen retention (Fig. 2), when compared with early terminated cover crops.

Results from this study showed no difference in soybean yield following a cover crop killed 3 weeks prior to soybean planting compared to a cover crop that was killed one day before soybean planting.

Experiments

The study consisted of three major experiments that included corn and soybean systems with and without the cover crop, winter cereal rye. The cover crop prior to corn was terminated about seven to 10 days before corn planting, while the cover crop prior to soybeans was terminated at two different times.