Use of Cover Crops for Improved Nutrient Management in Corn Production Systems.

Continual increased cost of synthetic fertilizers as well as increased interest in sustainable practices has increased interest in conservation minded production practices across much of the Mid-South.  One of these production practices is the utilization of fallow season cover crops.  While many regions across the United States have been investigating the use of cover crops for many years, this information is very limited in the Mid-South.  Therefore, field experiments were established in 2012 at two Louisiana locations to evaluate the effects of winter cover crops on corn production.  Factors tested included a factorial arrangement of five winter covers (previous crop residue, winter wheat, winter peas, hairy vetch, crimson clover, and forage radish) and two different N rates (optimum and sub-optimum) in a randomized complete block design.  Data collection focused on corn grain yield and nitrogen use efficiency (NUE).  Overall, forage radish and hairy vetch significantly improved corn grain yield compared to both the check and winter wheat.  While the other cover crops did not significantly improve crop yields, an agronomic improvement was found which improved yields by 10 and 20% for crimson clover and winter peas, respectively.  Additionally, NUE was improved for all cover crops compared to both the fallow and winter wheat treatments.  This indicates that cover crops can be utilized as a conservation-minded approach to improve corn production in the Mid-South.