This paper focuses on the naming and use of plants by Taita who live at Mount Kasigau in Kenya's Eastern Arc Mountains. Plant vouchers and ethnobotanical data were compiled from transects and within 55 ecological plots, and during participant observations, home surveys, and semi-structured interviews with residents. Between 2002 and 2006, we recorded 338 wild woody plants in 74 families and 208 genera. Kasigau Taita named 252 of these plants and described 758 material uses or ecosystem services for 205 plants. Most plants with uses occurred in montane woodland (650–1000 m), the bushland (<650 m) comprised most of the plant uses, and <7% of the plants in evergreen forest (>1000 m) had a described use. Local residents also enriched the availability of resources around their homes and farms. Extra-local pressures for commerce posed the greatest threat to biodiversity conservation and the sustainable provision of woody plant resources for local livelihoods.