Successional Trends in an Ungrazed, Arid Grassland Over a Decade

Abstract

A study has been made of the vegetational condition of a formerly grazed area, Chesler Park, in Canyonlands National Park. A comparison was made with the same area 10 years earlier. The 10-year successional changes are also compared to baseline data of 10 years earlier from Virginia Park, an adjacent ungrazed area. Because of inaccessibility and long isolation from disturbances, Virginia Park is presumed to be in climax condition and is the control for this study. Chesler Park shows a successional trend after 10 years toward the vegetational condition of Virginia Park. This is exemplified, with only one major exception (Hilaria jamesii), by responses of the perennial grasses (Stipa comata, Oryzopsis hymenoides, Sporobolus cryptandrus, Bouteloua gracilis) and the cryptogamic community, particularly the moss, Tortula ruralis. Species frequency, cover, vegetational characteristics, and stand classification support this conclusion. Prevalence of perennial grasses has declined and cryptogamic species have increased significantly.