In European mountain areas, shrub encroachment resulting from farmland abandonment is most often managed by mechanical operations such as roller chopping or controlled burning, which have proved to be ineffective and unsustainable. Recent agroecological findings highlight the potential impact of grazing on long-term shrub dynamics. We thus explored the potential contribution of livestock farms to the management of shrub encroachment. We studied the diversity of livestock practices and strategies on the scale of a small mountain valley in France where a land-use management plan was initiated. We interviewed 33 livestock farmers with a comprehensive approach and analysed the data in partnership with local land-use managers. To categorise farming practices, we used an innovative constructivist method based on knowledge engineering techniques and tools such as repertory grids. Our results show that the diversity of land-use practices can be summed up by ten practices related to three management domains: (i) livestock management, that is, splitting herds into batches, leading animals to pasture and breeding choices; (ii) the feeding system, including indoor feeding during the year, the hierarchy between haymaking and grazing in spring and the system’s forage autonomy; and (iii) farmland utilisation and maintenance, which comprises hillside use, spatial configuration of grazed areas, maintenance practices and technical choices to cut meadows. We also show that farmers combine these practices within six types of strategies: ensuring feeding security and simplifying labour (type A), maintaining farmland heritage (type B), taking advantage of hillsides (type C), focusing on animal care (type D), combining areas, periods and batches (type E), or selling on local markets (type F). This makes it possible to identify: (1) farmers’ strategies that have the greatest impact on shrub encroachment; and (2) practices that may develop into more sustainable management of shrub encroachment. Our work is thus a first step in developing sustainable land-use management plans in rural areas threatened by shrub encroachment. In return, this deep understanding of farmers’ strategies allowed us to address socially pertinent scientific issues related to the dynamics of grazed plant communities.