- Crop Production: cover crops, water management, water storage
Reducing weed pressure on crops without affecting soil health through intense and frequent tillage and cultivation practices is a major challenge in sustainable crop production. In recent years, cover crops are gaining importance as a sustainable practice that improves cropping system intensity and diversity as well as improving soil health and reducing weed pressure. However, few grain producers in the Southeast have included cover crops as part of their cropping systems because of several concerns. A major one being the possibility that cover crops may reduce the amount of water stored in the soil profile for the next grain crop, potentially reducing yields. The objective of this study was to evaluate the common fall cover crops in SC for soil moisture retention, biomass production, and water use efficiency. Soil water content was measured at 10, 20, 30, 40, and 60 cm depths at biweekly intervals starting from cover crop establishment. Biomass was measured at monthly intervals throughout the cover crop season. Cover crop water use efficiency was estimated as the amount of dry biomass produced per unit of water used during the growing period. Mixture of 5a, rye, and the mixture of rye and crimson clover produced the highest amounts of biomass in both seasons. These cover crops did not deplete soil moisture than did other cover crops or the fallow control in both seasons. The same cover crops also had the highest values for water use efficiency in both years. Water use efficiency is the ratio between biomass and water use. Since mixture of 5a, mixture of rye and crimson clover, and rye did not utilize more water than other crops, their higher water use efficiency is a result of higher biomass. The study provides information to develop grower recommendations on cover cropping to optimize biomass and soil moisture for subsequent crops.
Objective 1: Evaluate the common fall cover crops in SC for soil moisture retention, biomass production, and water use efficiency.