Soil Health of a Warm-Season Perennial Pasture Over-seeded with Cool-Season Annuals

View the project final report

Commodities

Practices

• Natural Resources/Environment: soil stabilization, winter annuals
• Soil Management: organic matter, soil chemistry, soil microbiology, soil quality/health

Livestock producers are always looking for ways to make their forage-based systems more economically and environmentally sustainable. One potential strategy is incorporation of a diverse mixture of annual grasses, legumes, and crucifer species over-seeded into a long-term commercial grazing operation. The grasses provide biomass both above ground for forage and below ground for soil microbial communities. The legumes fix nitrogen and incorporate it into the system. Crucifer species provide considerable root biomass and potentially retain soil moisture. The site is a bahiagrass (Paspalum notatum) perennial pasture located in southern Mississippi. The soil is a Loring Silt Loam, and area precipitation is approximately 150 cm annually. Soil samples will be collected and analyzed for physical, chemical, and biological properties. Bulk density and particle size analysis are the soil physical properties. Soil chemical assessments will include macronutrients, pH, soil organic matter (SOM), soil organic C (SOC), inorganic nitrogen and total nitrogen (TN) to 30 cm. The biological soil properties to be analyzed include fatty acid methyl ester biomarkers and the enzyme assays β-glucosidase and N-acetyl-β-glucosaminidase. The objective of this research is to determine the effect that cool-season annuals may have on soil quality in a warm-season perennial pasture over time and to determine the rate of change in soil health using this management strategy. This research may influence future decisions of livestock producers in how they manage their grazing operations.