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The purpose of this study was to produce a Holocene vegetation history of Capitol Reef National Park, Utah, by reconstructing past changes in vegetation and relating those changes to their most probable causes. Vegetation changes were reconstructed using plant macrofossils and pollen from 9 packrat middens ranging from 0-5400 years in age. All of the middens contain abundant macrofossils of Utah juniper (Juniperus osteosperma), saltbush (Atriplex spp.), cliff rose (Cowania mexicana), and prickly pear (Opuntia spp.), which are all plentiful at the site today. The presettlement middens also contain pinyon pine (Pinus edulis), winterfat (Ceratoides lanata), sagebrush (Artemisia sp.), and ricegrass (Stipa hymenoides), which are rare or absent from the single modern midden analyzed for macrofossils. Winterfat was not observed during the fieldwork, and pinyon pine was rare in the area. The rarity or absence of sagebrush and ricegrass from the modern midden suggests that they are less common now than prior to settlement. Hartnet #3, the modern midden, is the only midden containing viscid rabbitbrush (Chrysothamnus viscidiflorus), greasewood (Sarcobatus vermiculatus), and Russian thistle (Salsola sp.) macrofossils. Only the 2 most recent middens (#3 and #2) contain snakeweed (Gutierrezia sarothrae). Rabbitbrush, snakeweed, and Russian thistle are common at the site today. The absence of these species from presettlement middens indicates that these species were formerly absent, or so infrequent as to not be represented. Pollen of Utah Juniper increased during the last 20 years. These records demonstrate that the most severe vegetation changes of the last 5400 years occurred during the past 20 years. The nature and timing of these changes suggest that they were primarily caused by 19th century open-land sheep and cattle ranching.