Great Basin Naturalist


A synecological study of sagebrush-dominated rangelands was conducted on the Humboldt National Forest, northeastern Nevada, between 1983 and 1986. A total of 372 relatively undisturbed sites were sampled for both vegetation and soil parameters, with 35 grass, 39 shrub, and 140 forb species identified. Plant species production data were used to develop a hierarchical, floristic-based community type classification with TWINSPAN. Seventeen sagebrush community types were identified in this analysis and named by their dominant shrub and grass species. The dominant sagebrush species of the community types are Artemisia tridentata ssp. vaseyana (5 community types), A. tridentata ssp. wyomingensis (3 community types), A. tridentata ssp. tridentata (2 community types), A. arbuscula (3 community types), A. nova (3 community types), and A. longiloba (1 community type). Multivariate analysis revealed that all community types contain significantly different plant species compositions. Shrub species are more effective in discriminating between community types than grass species, which, in turn, are more effective than forb species.