Agricultural nutrient runoff and leaching into groundwater can impose societal costs that may be external to farmer decisions. Farmers can reduce the environmental impact of nutrient losses by adopting conservation and precision nutrient diagnostic and application practices. We examine the determinants of adoption decisions of such practices using mail survey data from a large, stratified sample of corn and soybean farmers in the U.S. Eastern Corn Belt. Via an ordered probit that captures both adoption and intent to adopt eight different practices, we evaluate a broad range of potential factors driving adoption of conservation and precision agriculture practices. We find that farmer objectives other than income, such as preferences for environmental amenities or social status, were important adoption drivers for conservation and precision technologies, respectively. Livestock farms had a distinct adoption profile, with greater likelihood to adopt cover cropping and less to adopt precision technologies. Farmers who participated in working lands programs were more likely to adopt both cover cropping and precision soil testing technologies. Policies and messaging to encourage voluntary adoption of practices to reduce agricultural nutrient loss should account for farmer objectives, farming systems, and existing policy incentives.