Interaction of fire and grazing in Oklahoma Artemisia filifolia shrubland

Abstract

Scope and Method of Study: We conducted research in Artemisia filifolia shrublands located in Woodward County, Oklahoma to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for three years (2006, 2007 and 2008) in replicated pastures grazed by cattle (Bos taurus) where the fire-grazing interaction had been restored (treatment pastures) and in pastures that were grazed but remained unburned (control pastures).

Findings and Conclusions: Vegetation structure in Artemisia filifolia shrublands of our study site was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. Most measurements of vegetation structure returned to levels characteristic of unburned sites within one to four years after being burned. The fire-grazing interaction changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Landscapes at our study site were characterized by an inherent amount of heterogeneity in vegetation structure due to variability in topoedaphic sites while the fire-grazing interaction superimposed an additional layer of heterogeneity.