Proceedings of the 2022 Mississippi Water Resources Conference

Year: 2022 Authors: Mullican N., Larson E., McCoy J., Lemus R., Krutz J., Bond J., Maples W.

Growing cover crops may restrict planting opportunities and corn productivity, particularly in high rainfall environments common in the Midsouth region of the U.S. This study was conducted to identify factors and management practices needed to successfully integrate cover crops into Midsouth corn production systems without sacrificing economic returns or increasing production risks. Field studies were conducted to evaluate effects of cover cropping cultural practices and species on corn growth and productivity in Mississippi in 2021. Various seeding methods affecting cover crop distribution, including strip tillage, had little influence on corn production systems. However, the presence of living cover crops at planting stunted corn growth and development when they were not terminated by herbicides applied at least two weeks prior to planting. This interference reduced corn grain yield compared to where no cover crops were grown, or cover crops which were terminated at least four weeks in advance of planting. These preliminary findings indicate that growing cover crops can hinder our ability to produce corn and implement early planting systems. Abundant vegetation produced by cover crops will shade the soil, restricting solar warming, which hinders corn seedling establishment and growth. Thus, growers seeking to gain benefits associated with growing cover crops must use herbicides to terminate cover crops at least a couple weeks in advance of planting in order to maintain corn productivity associated with early planting systems tailored for high rainfall, southern climates.