Spatial Impacts of Cattle On Cotton Production in a Conservation Tillage System On a Piedmont Landscape.

Winter annual cover crops can help offset cotton production costs in conservation tillage systems when grazed by cattle. However, management problems due to soil compaction and loss of surface residues may reduce yields. A four year study was conducted to evaluate cattle effects in conservation tillage cotton (Gossypium hirsutum L.) production system on Cecil soil (fine, kaolinitic, thermic, Typic Kanhapludult)at the USDA ARS research center in Watkinsville, GA. The four year average forage consumption was 2.6 Mg ha^-1 (dry matter basis) equivalent to $144 to $290 ha^-1. Wet weather during the 2009 grazing period resulted in compaction on the grazed fields and reduced cotton yields (0.64 Mg ha-1 vs. 0.42 Mg ha^-1). Spatial effects on yields were greater in camping and watering areas. Management zones assigned across the four fields by various clustering procedures helped identify soil and landscape characteristics that were correlated with increasing or decreasing yields. This information could be used to develop strategies for managing cattle to minimize effects of cattle in crop-grazed systems.