Observations of Grass Community Dynamics in Short Duration Grazing Systems in West Texas

Abstract

Short duration grazing (SDG) has played a major role in grazing management practices in North America over the past 2 decades. Among other things, implementation of SDG (i.e., cell grazing) reportedly improves livestock distribution within the grazing unit and improves range condition. The objective of this study was to evaluate density and frequency of the herbaceous vegetation as affected by distance from cell center, as well as changes in density and frequency over a 9-year period. Vegetation of the study area is considered a semidesert grass-shrub complex dominated by black grama (Bouteloua eriopoda Torr., Torr.) and multiple-stemmed honey mesquite (Prosopis glandulosa Torr.). Following implementation of SDG, density and frequency of herbaceous vegetation differed at various distances from the cell center. The spatial variability in plant response suggests that implementation of SDG did not result in uniform forage utilization. Secondly, there was an increase in density and frequency of perennial grasses over the 9 years of study. The increase in plant density and frequency may be related to SDG but it is likely that a principal cause of the positive response was favorable precipitation levels received during the study period.