Context. Land use change drives a host of sustainability challenges on Earth’s grasslands. To understand the relationship between changing land use patterns, human well-being, and ecosystem services, research is needed into land use transitions on privately-owned grasslands. Such inquiry lies at the intersection of land system science and landscape sustainability science. Objectives. This study investigated land use change in a mountain cattle ranching community in the Sierra Nevada, California. The research objective was to highlight the drivers and constraints of identified land use transitions and the types of landowners and policies influencing ecological outcomes. Methods. This research used a mixed methods case study based on participant observation, 30 semi-structured interviews, and analysis of land cover and real estate data from California’s Farmland Monitoring and Mapping Program, USDA CropScape, and a local real estate sales database. Interviews were conducted with ranchers, public agencies, and conservation and real estate industry representatives, and analyzed with the constant comparison method using Nvivo 12. Results. Land use transitions in the case study region include agricultural intensification, residential and solar development, and disintensification from amenity migration. These transitions were influenced by decreasing land access and water availability, remote work, intergenerational succession, and conservation policy. Conclusions. By highlighting influences on working lands, this study can be applied to improve the uptake of conservation policies. For the future, several factors appear critical to conserving ecosystem services on private grasslands: ensuring grazing lands access, income diversification, groundwater regulations, agriculture-compatible conservation easements, and land use policies supporting ownership transition to amenity purposes rather than low-density residential development.