The overall goal of the proposal is to determine the productivity, economics, and environmental benefits of establishing alfalfa by intercropping with sunflower or forage/grain sorghum. This will likely drive more growers to plant alfalfa in rotation with other crops in their system and increase the number of alfalfa acres. Increasing the acres of alfalfa will increase net returns to the farmers, decrease soil erosion and nutrient run-off to water sources, decrease soil organic carbon losses, reduce greenhouse gases emissions, and increase soil carbon sequestration and nitrogen supply to the cropping system.Objectives1. Evaluate the impact that intercropping alfalfa with sunflower or forage/grain sorghum planted at various row spacings has on alfalfa stand establishment, forage yield and nutritive value, nitrogen fixation and N crop utilization, and weed suppression.2. Evaluate the impact that integrating alfalfa into multi-cropping systems has on the physiological and molecular mechanisms associated with plant-plant interactions leading to altered alfalfa establishment, crop yield, nitrogen fixation and crop utilization.3. Assess the sustainability and impact of alfalfa intercropping systems to the environment and grower profitability.