Influence of Tillage and Deep Rooted Cool Season Cover Crops on Soil Properties, Pests, and Yield Responses in Cotton

Soil compaction is a significant problem in the Southeastern USA. This compacted zone or hardpan limits root penetration below this layer and reduces potential yield and makes plants more susceptible to drought induced stresses. Soil compaction in this region is managed using costly annual deep tillage at or before planting and there is a great interest in reducing and/or eliminating annual tillage operations to lower production costs. Deep rooted cool season cover crops can penetrate this compacted soil zone and create channels, which cash crop roots, such as cotton, could follow to capture moisture and nutrients stored in the subsoil. The cool season cover crop roots would reduce the need for annual deep tillage prior to planting, increases soil organic matter, which provides greater water infiltration and available water holding capacity. Field studies were conducted for two years with three different soil series to determine the effects of tillage systems and cool season cover crops on the soil chemical and physical properties, yield responses, and pest pressure. Results showed that cool season cover crops significantly reduced soil compaction, increased cotton lint yield and soil moisture content, reduced nematode population densities, and increased soil available P, K, Mn, and organic matter content compared to the conventional no-cover crop.