|Bates, Jonathan - Jon|
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/8/2006
Publication Date: 2/9/2007
Citation: Bates, J.D., Davies, K.W., Sharp, R. 2007. Prescribed fire and post-fire grazing response of sagebrush steppe vegetation[abstract]. Society for Range Management Meeting. Paper No.24.
Technical Abstract: In the Intermountain West, grazing guidelines recommend resting sagebrush steppe for at least two growing seasons following fire. The purpose of the policy is to allow herbaceous vegetation to recover and permit surface litter to accumulate to protect and enhance soil stability. However, the policy has not been adequately tested and as a consequence many managers have questioned its broad application. This study evaluated six grazing treatments over four growing seasons after fire on Wyoming big sagebrush steppe in eastern Oregon. The understory on site was co-dominated by Thurbers needlegrass, Idaho fescue, bluebunch wheatgrass, and Junegrass. Treatments included no grazing on burned and unburned treatments, two summer grazing treatments after fire, and two spring grazing treatments after fire. Treatments were replicated 5 times. Grazing utilization, by cattle, varied between 40-50%. Vegetation responses to treatments were evaluated by quantifying plant cover and density, clipping for standing crop, and measuring perennial grass seed production. Fire impacts to herbaceous perennials were rated to be of light to moderate severity. In the third and fourth growing seasons after fire, no differences were found among treatments for plant cover and density, and cover of litter and bareground. Standing crop for total herbaceous and perennial grasses, and perennial grass seed production differed among treatments in 2005 and 2006. Herbaceous and perennial grass standing crop was greatest in the ungrazed burn treatment and lowest in the unburned treatment. Total perennial grass seed production was highest in the ungrazed burn and summer grazed treatments and lowest in the unburned treatment. Seed production of perennial grass species tended to exhibit a similar pattern but species rankings varied by treatment. The results suggest that moderate grazing applied within the first two years after fire on sagebrush steppe may not limit herbaceous recovery.