AbstractFive vegetation communities in the alpine catchments of Lesotho were identified by hierarchical classification of the botanical composition data. Discriminant analysis indicated that these communities occupy particular topographic positions. The community‐environment relationships identified in this study were similar to those reported from other alpine areas of Lesotho. Grasslands at high altitudes are temperate in nature, with a high proportion of C₃ grass species. Below 2 950 m on the warmer aspects and below 2 750 m on south‐facing slopes, subtropical grass species (C₄) dominate the sward. Within the temperate and subtropical vegetation belts, slope orientation dictates the proportion of C₃ species present in the sward. It is proposed that topography acts to modify the factors that directly influence plant growth by modifying solar radiation patterns.