Fire and Rangelands

Sagebrush ecosystems of western North America are experiencing widespread loss and degradation by invasive annual grasses. Positive feedbacks between fire and annual grasses are often invoked to explain the rapid pace of these changes, yet annual grasses also appear capable of achieving dominance among vegetation communities that have not burned for many decades.

Sagebrush-steppe restoration has long been seen as a wicked problem—each case has multifaceted problems with no universal solutions—and thus managers have had to adopt adaptive management techniques to meet ever-changing landscape demands.

Large wildfires have increased in western US rangelands over the last three decades. There is limited information on the impacts of wildfires with different severities on the vegetation in these rangelands.

On the Ground: Invasive annual grasses pose a widespread threat to western rangelands, and a strategic and proactive approach is needed to tackle this problem. Oregon partners used new spatial data to develop a geographic strategy for management of invasive annual grasses at landscape scales across jurisdictional boundaries.

The exotic annual grass ventenata ( Ventenata dubia L.) is raising concern as it rapidly invades multiple ecosystem types within the United States, including sagebrush steppe, ponderosa pine forests, woodlands, and much of the Palouse and Pacific Northwest Bunchgrass Prairie (PNB).

The structure and composition of sagebrush-dominated ecosystems have been altered by changes in fire regimes, land use, invasive species, and climate change. This often decreases resilience to disturbance and degrades critical habitat for species of conservation concern. Basin big sagebrush (Artemisia tridentata ssp.

Western Governors on June 27, 2017 released the National Forest and Rangeland Management Initiative Special Report, highlighting mechanisms to bring states, federal land managers, private landowners and other stakeholders together to discuss issues and opportunities in forest and rangeland management.

The interaction between grazing and fire influences ecosystems around the world. However, little is known about the influence of grazing on fire, in particular ignition and initial spread and how it varies by grazing management differences.

Artemisia tridentata ssp. vaseyana ecosystems evolved with periodic fire, but invasive grasses, conifer encroachment, fire suppression, and climate change have resulted in altered fire regimes and plant communities. Post-fire increases in invasive annual grasses such as Bromus tectorum and reductions in native vegetation are common across the sagebrush steppe.

Fire can dramatically influence rangeland hydrology and erosion by altering ecohydrologic relationships. This synthesis presents an ecohydrologic perspective on the effects of fire on rangeland runoff and erosion through a review of scientific literature spanning many decades.