Mark P. Harrison1, Normie W. Buehring1, Andy R. Taylor1, Larry L. Falconer2, M. Wayne Ebelhar3, William L. Kingery4 and Shankar Ganapathi Shanmugam5, (1)North Mississippi Research and Extension Center, Mississippi State University, Verona, MS (2)Delta Research and Extension Center, Mississippi State University, Stoneville, MS (3)82 Stoneville Road, Mississippi State University, Stoneville, MS (4)Department of Plant and Soil Sciences, Mississippi State University, Mississippi State, MS (5)Plant and Soil Sciences, Mississippi State University, Mississippi State, MS
This is a report (2012-2014) on long-term studies (2011-2015) being conducted on a Marietta silt loam soil (non-irrigated), Verona, MS and a Bosket/Dubbs silt loam soil (irrigated) Stoneville, MS. The treatments are on the same site in a rotation with corn for the duration of the study. The objectives were to evaluate long term crop residue management (burn and no-burn corn crop residue) and annual fall applied one-pass tillage systems effects on bed height, ground cover, soybean yield and net returns. The studies were conducted as a split-plot with crop residue management as the main plots and tillage systems as the sub-plots. The economic analysis was based on enterprise budgeting returns above total specified cost (variable + fixed cost). Crop residue management influenced ground cover, yield, and net returns. The tillage systems were no-tillage on old beds, bed-roller, TerraTill® (in-row-subsoiler-bed-roller, one-pass implement) and disk (2x) + TerraTill. After two years (2012 and 2013) of no-tillage production on old beds, the beds were flat and had to be reshaped in the spring of 2014. The bed-roller and TerraTill spring bed heights were higher than disk (2x) + TerraTill and no-tillage. No-tillage and TerraTill spring ground cover (old crop residue and vegetation) most often had more ground cover than bed-roller and disk (2x) + TerraTill at both locations. No-tillage in 2012 and TerraTill and no-tillage in 2013 at Verona had more ground cover where the corn crop residue had not been burned. With irrigation (Stoneville), no-tillage and bed-roller yields and net returns were equal or higher than TerraTill and disk (2x) + TerraTill. However, in a non-irrigated environment (Verona), TerraTill yields and net returns were higher than no-tillage two of three years and higher than bed-roller one of three years. In 2013, not burning the corn crop residue (fall 2012) resulted in higher yields and net returns than burning the corn crop residue. Both locations indicated the disk (2x) operations did not increase yield or net returns.