Tracking on-farm innovative practices to support crop mixture design: The case of annual mixtures including a legume crop.

• 77 different crop mixtures were tracked down among 47 farmers. • The cropping practices varied with the farmers' objectives. • Functional processes are useful for understanding links between objectives and practices. • Various resources aiming at supporting crop mixture design were created. The use of crop mixtures can help to reduce environmental impacts of agriculture, while maintaining, or even increasing yield. However, farmers seldom use crop mixtures, due to a combination of obstacles characterizing a sociotechnical lock-in. The dominant system remains the cultivation of pure crops, with acknowledged environmental impacts, but some innovative farmers are experimenting crop mixtures. This study aimed to identify and analyze the crop mixtures grown by these farmers, with a view to creating cognitive resources to help other farmers to adopt and adapt this practice to their own context. The on-farm innovative practices tracking method was implemented in Center-West and Southwest France. We surveyed 47 farmers who were already growing crop mixtures. Semi-structured interviews were conducted to identify the crop mixtures grown by these farmers, the objectives targeted with these mixtures, the crop management applied, and the farmers' satisfaction criteria. In total, 77 combinations involving 29 different species were found. Most of the mixtures included grain or forage legumes. We distinguished seven types of crop mixtures, based on their seasonal or temporal organization, and the target outlets for the mixtures. Each type of crop mixture was associated with a particular set of farmer's objectives. Crop management practices for mixtures of similar species sometimes differed considerably between farmers. An analysis of the agronomic rationale of farmers revealed consistency between technical choices, farmer's objectives and farm context. Based on an agronomic cross-analysis of these on-farm innovative practices, we generated actionable knowledge and cognitive resources to support farmers and agricultural extension workers wishing to redesign their cropping systems to make them more sustainable. [ABSTRACT FROM AUTHOR]