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Reevaluating assumptions about the ecology and management of sagebrush and salt desert shrub systems in the Great Basin and Intermountain West is a proper role for science. These are complex rangeland ecosystems, and our management applications need to account for this complexity. Understanding and reckoning this complexity is vital to the future existence of these rangeland systems and their ability to provide critical goods and ecosystem services to society. The most influential ecological claim of the past 40 yr is based on ideas presented by Mack and Thompson (1982), that Great Basin and Intermountain West plant communities evolved with few or perhaps no large hooved-grazing animals. Our thesis asserts that Mack and Thompson's position is based on 1) an oversimplification of complex, heterogeneous, and diverse ecosystems; 2) a poor understanding of science, both in 1982 and now; and 3) the attribution of all recent ecological changes to a single land use. We review the archaeological and historical record of vegetation and large grazing animals in the region and then revisit Mack and Thompson's (1982) interpretations of the rangeland plants and plant communities, forage quality and nutrition, and soil biotic crusts east and west of the Rocky Mountains, adding the information necessary for a more comprehensive interpretation. We finish by proposing an alternative paradigm to guide management and conservation of sagebrush and salt desert systems of the Great Basin and Intermountain West and beyond.

Cheatgrass (Bromus tectorum L.) seedlings suffer mortality if they do not occupy safe sites that provide establishment requirements. Previous research demonstrated that fall cattle grazing has strong potential for reducing invasive annual grass species dominance in winter-dominated precipitation areas of the Intermountain West. Fall cattle grazing reduces the volume of safe sites through the removal of standing dead biomass in the fall and early winter, when cheatgrass can actively germinate. This study continued an assessment of cheatgrass seed bank characteristics under fall-grazing and grazing exclusion treatments initiated by a previous study. A seed bank assay was organized into a randomized complete block, repeated measure design to assess cheatgrass seed bank characteristics from 2014 to 2017 in central Nevada. Across years, fall-grazed areas had about half the assayed seed bank levels (3 432 ± 2 513 seeds ∙ m−2) of ungrazed areas (7 187 ± 1 569), (P

On the Ground There are now over 130,000 head of wild horses and burros in the Bureau of Land Management program. Management tools in the original authorizations (Wild Horse and Burro Act; Public Rangelands Improvement Act) have been inhibited or banned by subsequent appropriation riders. The original framework for horse and burro management has been undermined, leading to on-range populations in excess of legally mandated levels. New, creative approaches to horse and burro management are required to bring populations back to legally mandated and ecologically appropriate levels.

On the Ground • Over 400,000 km2 of the Intermountain West is colonized by cheatgrass and other annual grasses. • Planning and management actions designed to foster perennial grass health throughout the region have never addressed how annual grasses would respond. • For decades, the most significant landscape-level management approach toward invasive annual grasses has been to complain. • We now know how to begin the process of taking the Intermountain West back from the domination of invasive annual grasses: through the management of standing dead litter. • Sustaining perennial bunchgrasses at landscape scales will require an integrated ecological approach to fuels management.

Fire kills Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) and promotes cheatgrass (Bromus tectorum L.), a highly flammable and invasive annual in sagebrush communities with compromised resistance. To focus management on resistance and resilience of Wyoming big sagebrush communities with varying species composition, we studied 51 paired sites with burned and unburned areas. We quantified soil surface and foliar cover in 12 cover groups. Comparisons identified vegetation or soil surface factors that significantly (p ≤ 0.05) correlated (Spearman's rank correlation coefficient = ρ) to burned area community composition. Cheatgrass cover in burned areas was greater where unburned areas had more cheatgrass cover (ρ = 0.75), litter cover (ρ = 0.31), and sagebrush plant canopy volume (ρ = 0.40), and less bare soil (ρ=-0.39) and cryptogamcover (ρ=-0.32). Cheatgrass cover in burned areas was not significantly correlated with unburned area perennial grass or forb cover. Burned area perennial grass cover appeared to be related to more perennial grass (ρ = 0.77) and native forb cover (ρ = 0.30), but less cheatgrass cover (ρ = -0.39) in unburned areas. Burned area native herbaceous dominance (native minus exotic herbaceous foliar cover) correlated with less cheatgrass cover (ρ = -0.65) and sagebrush canopy volume (ρ = -0.34) in unburned areas and with more perennial grass (ρ = 0.30) and sagebrush relative cover (ρ = 0.39) in adjacent unburned areas. Postfire site dominance could be of either native or exotic plants where cheatgrass cover on adjacent unburned sites was < about 15%. Native species however, never dominated or increased in dominance where cheatgrass was above 15%. Results suggest that cheatgrass cover before a fire played a strong role in determining postfire plant communities; this suggests management should focus on prefire and postfire management of cheatgrass and litter. Perhaps prescriptions and priorities should bemore nuanced on the basis of driving variables of postfire response hypothesized to be cheatgrass, perennial grass, and shrub abundance.

Many Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis) communities are invaded by exotic annuals, especially cheatgrass (Bromus tectorum L.), promoting larger and more frequent wildfires. Mowing sagebrush can reduce fire risk. To identify community features favoring regeneration of native perennials over exotic annuals, we compared paired, adjacent unmowed and mowed areas treated between 2001 and 2010 at 76 sites across northern and central Nevada. We quantified soil surface and foliar cover in 12 cover groups, as well as slope, aspect, elevation, and time since mowing (0–10 years). We identified unmowed cover characteristics and site covariates that best predicted herbaceous cover in mowed areas and differences in herbaceous cover between adjacent mowed and unmowed areas. Mowed areas had significantly (P < 0.01) more absolute cover (%) of litter (14.6), perennial grasses (4.9), cheatgrass (2.0), and exotic forbs (1.1) and less sagebrush (-13.5), bare soil (-11.4), moss (-3.3),...

Wildfire is a major concern in the Intermountain West. Fuels management can lower the potential for negative wildfire effects. Cheatgrass (Bromus tectorum L.), a nonnative annual grass, invasion has resulted in a buildup of highly flammable fine fuels that promote frequent wildfire. Removal of cheatgrass standing crop through targeted, prescriptive grazing should provide a reduction in fire intensity and possibly frequency on a local basis. Spring cattle-grazing prescriptions have provided critical reductions in cheatgrass standing crop and seed production. However, annual fluctuations in timing of readiness and standing crop production pose planning difficulties for both producers and land managers. With fall grazing, the uncertainties are no longer planning obstacles. We examined the effects of pasture-scale fall grazing of cheatgrass by cattle on standing crop (fuel reduction), the perennial vegetation community, and cattle performance. Fall grazing removed significant amounts of cheatgrass standing crop during 2006 to 2009: 79, 80, 79, and 58%, respectively. Cumulatively, 675 kg/ha were removed from the fuel base, significantly reducing carryover fuels. With protein supplementation, cattle increased BCS and gained BW in all 3 yr of the assessment (0.17, 0.35, and 0.29 kg/d in 2007 to 2009, respectively). Cheatgrass seed bank decreased by 6-fold in the grazed treatment and a little more than 2-fold in the ungrazed area 2007 to 2009. Perennial plants increased standing crop production at the expense of cheatgrass production. Fall grazing of cheatgrass can remove significant amounts of fine fuel with beneficial effects to grazing animals and the perennial plant community.

Until recently, most contemporary ecologists have ignored or diminished anecdotal historical accounts and anthropologists' reports about aboriginal fire in the Great Basin. Literature review shows that Indians practiced regular use of fire for many purposes, including the obvious reasons of increasing the availability of desired plants, maintaining habitats for animals used as food, and driving game during hunts. Historical accounts of prehistoric anthropogenic firing, inferences from fire-scar data, and data regarding annual production capability of representative sagebrush (Artemisia spp.)-perennial grass ecological sites indicate that prehistoric conditions were neither fuel- nor ignition-limited. According to many sources, this “active management” by Indians was widespread, significant, and more common than lightning-caused fires, resulting in mosaic vegetation patterns that subsequently moderated the behavior of “natural fires.” This interaction between Indian-burning and lightning fires may have strongly influenced the pre-Euro-American settlement vegetation of the Great Basin. At the very least, the landscape was a patchwork of areas altered by aboriginal people and areas shaped primarily by bio-physical processes. Based on this prehistoric precedent, current historically unprecedented conditions (fuel load and exotic weed invasion threats), and predicted climate change, contemporary active management of sagebrush-perennial grass communities is paramount. Restoration measures should be scientifically based and tailored to achieve ecological resilience and functionality in specific sites. Prescribed fire is not always ecologically appropriate or judicious, especially in Wyoming big sagebrush (A. tridentata spp. wyomingensis) communities, so managers should consider using other alternatives where an intentional low severity distubance is deemed necessary. Properly planned active management would disrupt fuel continuity for lighthning fires, ensure ecological process and successional integrity, and benefit multiple uses on a landscape scale.

Vegetated wetlands at Owens Dry Lake, California, are embedded in a large arid region. The wetlands initially established when Owens Lake desiccated in the early 1900s, and largely exist below the historic shoreline, due to ground-water discharge. MSS satellite imagery was used to measure the coverage of wetlands on five dates from 1977 through 1992. Coverage from vegetated wetlands both declined and increased during the study period, and appeared to have an inverse relationship with annual runoff in the hydrologic watershed. Also, soil and/or water chemistry appear to interact with ground-water elevation to affect the wetland's spatial dynamics.

Book Review: A Field Guide to Nevada Shrubs, Barry L. Perryman. Indigenous Rangeland Management Press, Lander, WY, USA (2014).

Book Review: A Field Guide to Nevada Grasses, Barry L. Perryman, Quentin D. Skinner. Indigenous Rangeland Management Press, Lander, WY, USA (2007).