Historical changes in plant dominance, in two town- ships ofSkull Valley, UT, were assessed by repeating the earlier descriptions made by surveyors from the General Land Office. Massive conversions to cheatgrass and other annuals offormer sagebrush- and shadscale-dominated vegetation on bench, foothill, and bajada sites were found. In addition to unrestricted livestock grazing, wildfires were identified as the probable triggering factors for these changes. Both forces were probably required for conversion to dominance by annuals. Juniper at higher elevations, lesser grazed areas at mid-elevations, and greasewood-, salt grass-, and pickleweed-dominated areas at lower elevations have undergone much less change.