Area of Pristine Vegetation in Craters of the Moon National Monument, Idaho

A 180—acre kipuka near Carey, Idaho, surrounded by rough lava areas has apparently never been grazed. The entire kipuka is covered by the sagebrush—grass types of which three communities have been recognized and described: the Artemisia tripartita/Festuca idahoensis, the A. tridentata/Festuca idahoensis/Agropyron spicatum, and the A. longiloba/Festuca idahoensis/Stipa thurberiana communities. Chestnut soils of the kipuka developed on loess show considerable influence of the residual basalt, and differences in aspect and depth are closely associated with the occurrence of the three plant communities. The kipuka is now protected and is being used for studies of sagebrush—grass ecosystems. Fluctuation in the relatively stabilized vegetation is evident with recent deterioration of Festuca and its replacement by Bromus tectorum, presumably a result of drought.