Implications of Longer Term Grazing Rest in the Sagebrush Steppe

Abstract

Longer term grazing rest has occurred or been proposed in large portions of the sagebrush steppe based on the assumption that it will improve ecosystem properties. However, information regarding the influence of longer term rest from grazing is limited and has not been summarized. We synthesized the scientific literature on long-term rest in the sagebrush steppe to evaluate the potential ecosystem effects and identify factors that influence those effects. Longer term rest is clearly advantageous compared to detrimental grazing practices (i.e., repeated defoliation during the growing season without periodic deferment or short-term rest). Changing grazing management from detrimental use to modern recommended grazing practices or dormant season use will likely convey the same benefits as long-term grazing rest in most situations. In general, long-term rest and modern properly managed grazing produce few significant differences. However, some topic areas have not been adequately studied to accurately predict the influence of long-term rest compared to managed grazing. In some situations, long-term rest may cause negative ecological effects. Not grazing can cause an accumulation of fine fuels that increase fire risk and severity and, subsequently, the probability of sagebrush steppe rangelands converting to exotic annual grasslands. One common theme we found was that shifts in plant communities (i.e., exotic annual grass invasion and western juniper encroachment), caused in part from historical improper grazing, cannot be reversed by long-term rest. This synthesis suggests that land managers should carefully consider if long-term rest will actually achieve their management goals and if a change in grazing management would achieve similar results