Grazing diversified cover crops as an alternative to improve land-use efficiency and sustainability in the Southeast

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Commodities

Practices

• Animal Production: grazing management
• Crop Production: cover crops, crop rotation
• Production Systems: integrated crop and livestock systems

Diversification of cropping systems by increasing number or type of cover crops in crop rotation plays an important role in improving land-use efficiency and in promoting sustainable agriculture. Preliminary data indicate that the implementation of cover crops in cropping systems may provide a myriad of ecosystem services in agricultural systems. Among the ecosystem services provided, one can have increasing soil organic carbon sequestration, breaking pest and disease cycles, reducing erosion and nitrate leaching, and decreasing weed pressure. Moreover, integrating livestock into cropping systems, by grazing cover crops into a crop rotation system, has the potential to promote increased market diversification, increased economic return, enhanced nutrient cycling, and sustainability. Combining different forage species in the same area simultaneously in a cropping system can enhance soil quality and improve nutrient availability to crops. The combination of different functional groups of forages as cover crops has the potential to extend the benefits to improve yields and reduce nitrogen inputs, allowing for a more efficient use of resources, and reduce environmental impacts. Although some studies have investigated the effect of cover crops on cash crop production, soil and water quality, and environmental impacts, little has been done to investigate the effect of intercropping and grazing multi-species cover crops on the whole cropping system, from cover and cash crops to animal production and other ecosystem services. The objective of this proposal is to 1) evaluate how different grazed cover crops systems consisting of an annual grass as monoculture or in combination with a legume or with legume-brassica mixture influences the plant, animal, and environmental interfaces, 2) determine the best combination of different varieties of oats and crimson clover in the Southeast, 3) assess the contribution of cover crop use on soil organic matter formation and greenhouse gas emissions, and 4) create a reference booklet to increase awareness of the benefits of legumes in the forage systems in the Southeast. The project team, consisting of two livestock specialists, two forage specialists, one plant breeder, and a postdoctoral fellow, will implement the mixtures as cover crops in an already established cotton cropping system to determine forage agronomic characteristics, animal performance, soil health parameters, and environmental impact parameters over two years. This study will provide Southeastern crop producers with science-based information and recommendations on utilizing diversified cover crops in crop rotation systems to improve their farming systems profitably and sustainably. Three field days will be held over a 3-year period to disseminate the findings to crop producers throughout the states of Alabama and Florida. Findings from the study will also be published using established social media outlets and online websites (e.g., alabamaforages.com). Extension and peer-reviewed articles will be submitted during Year 3 of the proposal. Transfer of knowledge to crop producers will be assessed to evaluate the impact of the outreach program. The proposed booklet will be distributed at the International Grassland Council meeting in May 2023 (n = 500 copies) and other forage-related.

1. Determine the effect of grazing multi-species cover crops on soil characteristics and cover crop performance and to understand the role of cover crops on soil organic matter formation.
2. Determine the effect of grazing multi-species cover crops on forage production and quality and animal performance.
3. Determine the effect of grazing multi-species cover crops on commodity crop yield.
4. Assess the level of genotype-by-management interaction of multi-species cover crops.
5. Develop an Extension and outreach program to create awareness on and disseminate knowledge of multi-species grazed cover crops to farmers, Extension agents, and researchers.