There is limited information on the effects of cattle grazing to long-term plant community composition and productivity following fire in big sagebrush steppe. This study evaluated vegetation response to cattle grazing over seven years (2007-2013) on burned Wyoming big sagebrush (Artemisia tridentataÂ ssp.Â wyomingensisÂ (Beetle & Young) Welsh) steppe in eastern Oregon. Treatments, replicated 4 times and applied in a randomized block design, included no grazing on burned (NON-USE) and unburned (CONTROL) sagebrush steppe; and grazing at low (LOW), moderate (MODERATE), and high (HIGH) stocking. Vegetation dynamics were evaluated by quantifying herbaceous (canopy and basal cover, density, annual yield, reproductive shoot weight) and shrub (canopy cover, density) response variables. Differences in herbaceous response variables among LOW, MODERATE, and NON-USE treatments were nonexistent or minor and no major compositional changes occurred. The HIGH treatment had lower perennial bunchgrass cover and annual yield than other grazed and NON-USE treatments. Bunchgrass density remained unchanged in the HIGH treatment, not differing from other treatments, and reproductive effort was comparable to the other treatments indicating these areas are potentially recoverable by reducing stocking. Cover and yield ofÂ Bromus tectorumÂ L. (cheatgrass) did not differ among the grazed and NON-USE treatments, though all were greater than the CONTROL. Cover and density ofÂ A.t.Â spp.Â wyomingensisÂ did not differ among the grazed and NON-USE treatments and were less than the CONTROL. We concluded that light to moderate stocking rates are applicable to sustainable grazing of burned sagebrush steppe.
CATTLE GRAZING AND VEGETATION SUCCESSION ON BURNED SAGEBRUSH STEPPE
Society for Range Management
SRM Sacramento, CA