Woody fuels reduction in Wyoming big sagebrush communities

Authors: SCHUPP, EUGENE - Utah State University; Boyd, Chad; GREEN, SHANE - Natural Resources Conservation Service (NRCS, USDA)

Submitted to: Government Publication/Report
Publication Type: Government Publication
Publication Acceptance Date: 9/30/2015
Publication Date: 11/20/2015
Citation: Schupp, E.W., Boyd, C.S., Green, S. 2015. Woody fuels reduction in Wyoming big sagebrush communities. Sage Grouse Initative. Great Basin Factsheet Series. Number 13:1-6. Available: http://www.sagegrouseinitiative.com/wp-content/uploads/2015/11/GB-Factsheet-13-Woody-Fuels-Reduction-in-Wyoming-Big-Sagebrush-Communities.pdf

Interpretive Summary: Shrub fuels in exotic annual grass-prone Wyoming big sagebrush communities have increased in recent decades, leading to larger and more severe wildfires that compromise maintenance of native perennial plants and associated wildlife habitat. We reviewed literature documenting the effects of shrub fuel reduction practices on plant community resistance to weed invasion and quality of wildlife habitat, and present guidelines to help maximize the probability of positive outcomes. Post-treatment increases in exotic annual grasses and impacts of treatments on shrub-dependent wildlife species are major concerns when implementing shrub reduction treatments and these issues can be minimized by ensuring adequate pre-treatment cover of perennial bunchgrasses, selecting shrub reduction techniques that minimize ground disturbance, and limiting the spatial extent of treated areas. Balancing the need for shrub fuel reduction in Wyoming big sagebrush communities with potential negative unintended consequences will remain challenging because these communities have slow recovery from management treatments and low resistance to annual weeds.

Technical Abstract: Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) ecosystems historically have been subject to disturbances that reduce or remove shrubs primarily by fire, although insect outbreaks and disease have also been important. Depending on site productivity, fire return intervals occurred every 60-110 years. Following fire, perennial grass-dominated plant communities slowly underwent succession to return to a community co-dominated by sagebrush and perennial grasses. Due to historical and in some cases recent overgrazing, many Wyoming big sagebrush communities have undergone changes in plant community composition, primarily a decrease in the density and cover of native perennial grasses and forbs. The consequences of this loss of understory herbaceous species have been an increase in annual weed cover and, in many cases, shrub cover. Increases in annual weeds such as cheatgrass (Bromus tectorum L.) result in more fine fuels, greater fuel continuity, and more frequent fires. The increase in woody fuels has led to - more severe and larger fires during periods of extreme fire weather. Management to address these changes in fuels and fire behavior is challenging in Wyoming big sagebrush communities because warm and dry conditions coupled with low productivity result in (1) low resilience and thus slow recovery following both wildfire and management treatments, and (2) low resistance to annual weeds.