Exotic annual grass invasion and dominance of rangelands is a concern across western North America and other semiarid and arid ecosystems around the world. Postfire invasion and dominance by exotic annual grasses in sagebrush communities is especially problematic as there are no cost-effective control strategies available for the vast acreages already invaded. However, fall-winter grazing by cattle has been suggested as a potential tool to decrease exotic annual grasses and encourage native perennial vegetation, but to date its efficacy has not been tested. We evaluated fall-winter grazing over 4 yr after wildfire in Wyoming big sagebrush (Artemisia tridentata Nutt. subsp. wyomingensis Beetle & Young) steppe invaded by exotic annual grasses. Fall-winter grazing reduced exotic annual grass and annual forb cover and density and increased the native perennial bunchgrass, Sandberg bluegrass (Poa secunda L.). Exotic annual grass cover and density were 1.5 × greater in ungrazed compared with fall-winter grazed areas after 4 yr. At this time, Sandberg bluegrass density and cover were 1.6 × and 2.3 × greater in fall-winter grazed compared with ungrazed areas. Large perennial bunchgrasses and perennial forbs did not increase with fall-winter grazing because either grazing did not facilitate their increase or they were slow to respond to decreases in exotic annuals. Fall-winter grazing likely decreased exotic annual grass by defoliating it during its early growth in the fall and late winter and by reducing ground cover that facilitates exotic annual grass emergence and growth. Fall-winter grazing clearly reduced exotic annual grasses, but its effects on native perennial vegetation were not conclusive. Careful application of fall-winter grazing appears to be a valuable tool for managing exotic annual grass cover and abundance, but longer-term research is necessary to determine if it can facilitate the return of native perennial dominance.

Water is an important nutrient, and its continuous provision is a critical welfare issue for cattle grazing arid and semiarid rangelands. Time and labor are needed to monitor water availability, and automated monitoring systems are a costly input on expansive rangeland pastures. The objective of this study was to evaluate the potential of detecting water system failures using Global Positioning System (GPS) tracking and accelerometers, assuming the data could be monitored in real or near-real time. Water system failure was simulated in a 1 096-ha pasture in Arizona by placing metal panels around the only drinker for 4 h (0800–1200) on three occasions in 2018 and two occasions in 2019. Randomly selected cows (10 in 2018 and 23 in 2019) of the 120 cows in the pasture were tracked with GPS collars, and 7 (2018) and 10 (2019) of the tracked cows were fitted with triaxial accelerometers. Movement intensity measured by accelerometers was greater (P = 0.03) on the day of simulated water failure than on control days with available water. During simulated water failure, cows remained closer to water (P = 0.01) after approaching the drinker (< 150 m) compared with the control period the day prior. Cows typically went to the drinker, drank, and then traveled away from the drinker and rested. On simulated water-failure days, cows remained near the drinker (< 150 m from the tank) until the panels were removed and they could drink. Real-time GPS tracking with or without accelerometer data has the potential to remotely detect water system failure, which could reduce the time for managers to repair the water system and improve cattle well-being.

Collaborative adaptive management is a means to achieve social and ecological goals in complex natural resource management settings. Evaluation of collaborative management outcomes, however, is difficult at the scale of large landscapes. We developed an approach for such evaluations using long-term, spatio-temporal gridded or county-level datasets alongside local information on changes in ranch ownership. We applied this approach to evaluate the sustainability goals of the Malpai Borderlands Group (MBG) by comparing the MBG landscape to surrounding, similar desert grassland landscapes. We matched datasets, where possible, to management goals, including the preservation of ranching livelihoods, prevention of rangeland fragmentation by exurban development, sustaining the ecological role of fire, limiting or reversing woody plant encroachment into grasslands, sustaining rangeland productivity, and sustaining biodiversity. We found that the number of ranch families changed little since MBG was established, although several ranches were consolidated within some families or absentee owners, such that multiple families share other ranches. The number of beef cattle ranches declined within one MBG county, likely due to increasing depth to groundwater. Exurban development and rangeland-to-cropland conversion have been virtually nonexistent in the MBG landscape, while such conversions are common in adjacent landscapes. Coordinated fire planning with low fragmentation of rangeland has led to extensive fires in the MBG landscape, dwarfing the area burned in adjacent landscapes. The percent of land area exhibiting significant trends of increasing bare ground cover was intermediate in the MBG landscape compared with adjacent landscapes, while herbaceous and shrub cover exhibited significant trends in only a small fraction of the study region. Rangeland productivity exhibited significant declines in some landscapes, but declines were minimal in the MBG area. Our analysis suggests that collaborative adaptive management implemented by the MBG has aligned with their goals, but changing climate, water availability, and demography will become increasingly challenging.

Non-native plants alter conditions and can reduce the effectiveness of restoration tools. Under these conditions, adding native, locally adapted seeds to favor establishment of native plant communities may provide a potential restoration strategy. We explored the efficacy of soil disturbance and the addition of native seed to restore native plant and arthropod communities in landscapes dominated by Kleberg bluestem (Dichanthium annulatum [Forssk.] Stapf, Old World bluestem grasses, OWB) in summers 2011–2013; our study coincided with severe drought. We compared vegetation and arthropods on disked plots with and without seed (experimental plots), as well as plots within adjacent, undisturbed OWB monocultures. Adding seeds increased cover of native plants and reduced cover of OWBs relative to unseeded plots and undisturbed OWB monocultures. Most of the plants we recorded in seeded plots were not included in the seed mix; we hypothesize that arthropods may have been consuming the added seed rather than the seed bank, permitting native plants in the seed bank to establish. Adding seed also increased arthropod species richness, which was more pronounced as drought severity decreased. During severe drought, arthropod abundance in experimental plots was comparable with undisturbed OWB monocultures, despite the absence of vegetation after disking. However, as drought subsided, undisturbed OWB monocultures had more arthropods than experimental plots. Non-native arthropods, particularly herbivores, were positively associated with OWBs; adding seed was associated with reduced dominance of both OWBs and nonnative arthropods. Reducing dominance of OWBs by adding seed was also associated with reduced dominance of some predators that consume non-native arthropod prey. Understanding how communities respond to multiple disturbances seems especially important to inform restoration strategies given that changes in climate patterns and establishment of invasive species are likely to be more common and widespread.

Irrigation of farmlands in xeric areas can increase soil salinity, reducing their suitability for food and fiber crops. One way to repurpose these lands is to convert them for use in grazing. To choose the best forage species, it is important to understand the impact of soil salinity on the growth and nutritional quality of potential forage grasses. Here, we grew four perennial C₄ grasses: blue grama (Bouteloua gracilis), sideoats grama (Bouteloua curtipendula), little bluestem (Schizachyrium scoparium), and bermudagrass (Cynodon dactylon) in soil treated with four different concentrations (0, 8, 16, and 24 dS/m) of sodium chloride salt (NaCl). We then determined the effects of soil salinity on germination, biomass production, and plant tissue nitrogen content (an indicator of nutritional quality). We found a high degree of variability in salinity responses among species. S. scoparium performed poorly relative to the other species across all metrics. C. dactylon showed high biomass and low sensitivity to soil salinity for each index but had the lowest shoot nitrogen concentration of all species tested. This indicated a tradeoff of tissue quality for quantity. On the other hand, the two Bouteloua species showed opposite results, falling on the shoot quality end of the quantity-quality spectrum and even showing increased nitrogen concentration with increasing soil salinity. Given their complimentary traits, C. dactylon and Bouteloua spp. may be good candidates for interseeding on saline lands. These results indicate that species choice can help mitigate negative impacts of soil salinity on forage production and quality and should be carefully considered by land managers.

Adaptive management of natural resources explicitly incorporates learning into a process of science-based decision making. First proposed in the late 1970s, over time, adaptive management has become an increasingly common approach to management of complex social-ecological systems characterized by high uncertainty and conflict. Rangelands used for livestock production are one such system. Management outcomes of any given livestock operation are a unique combination of the local ecology found in a particular place, the management goals and approach of the operator and regulators, and regulatory requirements. Scholars have hypothesized that adaptive management can reduce conflict by allowing experimentation and increased management flexibility when there are competing viewpoints. We used a change to adaptive management for grazing allotment administration implemented by the US Forest Service in Arizona and New Mexico to evaluate this research question. We interviewed ranchers and Forest Service employees in Arizona and New Mexico to understand how they define adaptive management, what changes they experienced due to the shift to adaptive management, and their perceptions of the impacts of adaptive management. A decade after its implementation, our data show that adaptive management alone does not reduce conflict but can help reduce conflict where trust between permittees and the US Forest Service is strong. Where trust is lacking, adaptive management may strengthen existing patterns of conflict. These findings have important management implications for the use of adaptive management in the administration of public lands and as a conflict management tool.

Woodland expansion is a global challenge documented under varying degrees of disturbance, climate, and land ownership patterns. In North American rangelands, mechanical and chemical brush management practices and prescribed fire are frequently promoted by agencies and used by private landowners to reduce woody plant cover. We assess the distribution of agency-supported cost sharing of brush management (2000–2017) in the southern Great Plains, United States, and evaluate the longevity of treatment application. We test the general expectation that the current brush management paradigm in the southern Great Plains reduces woody plants and conserves rangeland resources at broad scales. This study represents the most comprehensive assessment of treatment longevity following brush management in the southern Great Plains by linking confidential private lands management data to a national inventory program (US Department of Agriculture Natural Resources Conservation Service National Resources Inventory). We observed regional differences in the types of brush management techniques used in cost-sharing programs throughout the study area. Mechanical brush management was the most common practice cost shared in Texas, while a mixture of mechanical and chemical application was most common in Oklahoma. Prescribed fire was most common in Kansas with some areas receiving chemical treatment. Our analysis showed brush management, as implemented, did not reduce tree cover long term and minimally reduced shrub cover. Evidence to support the current brush management paradigm only existed at local site-level scales of analysis (40- to 50-acre area), but treatment effectiveness was short-lived. At regional scales, observed changes in woody plant cover showed little to no overall net reduction from 2000 to 2017. These findings bring into question the philosophy of the current brush management paradigm, its implementation as the default rangeland conservation practice, and its prioritization over alternative practices that prevent new woody plant establishment and enhance resilience of rangelands in the southern Great Plains region.

Conservation practices can maintain or enhance the quantity of ecosystem services realized by both private individuals and society. However, implementing these practices generally has costs that may exceed the benefit received by a private economic agent, particularly if costs are immediate and benefits accrue in the future. This study presents a framework to evaluate ranch-level financial incentives for grazing management that results in improved soil health. A range of hypothetical scenarios of improved forage production is considered for a representative central-Wyoming, US, profit-maximizing rancher. Modeled scenarios are then compared with the possible costs of implementing a practice to improve soil health. The net present value (NPV) of net benefits is shown to be positive if forage production increased immediately. However, it is likely that the forage response is not immediate and would occur over a significant period of time. Scenarios of linear and logistic forage response over a period of 35 yr and 105 yr, as well as two different initial conditions, all show a negative NPV of net benefits (greater implementation costs of rotational grazing than projected benefits from improved soil health) assuming a 7% discount rate. Due to the time it may take for forage benefits to be realized and the time value of money, financial assistance may be required for ranchers to at least break even when implementing practices that improve soil health on rangelands.

Pronghorn (Antilocapra americana) evolved in grasslands with a diet composed of highly nutritious forbs. However, pronghorn habitat throughout North America has been lost to fragmentation and degradation. Additionally, the effects different cattle grazing regimes have on forb biomass, protein, and energy production for pronghorn are not well known in West Texas. We sampled forbs during the growing season in the months of September 2018 and 2019 to assess the effects of different cattle grazing regimes on forbs. We hypothesized rotational grazing would increase the nutritional quality of the forb community and overall forb production, compared to continuous grazing and no grazing. We randomly sampled pastures subject to continuous and rotational grazing, as well as ungrazed exclosures using 100, 96, and 64 1 m² plots, respectively. We collected all forbs in each plot and analyzed differences in nutritional composition and biomass production using redundancy analysis. We found that the effects of grazing varied by year. In wetter conditions, rotational grazing exhibited higher forb quality and biomass, while exclusion from grazing exhibited these results under drier conditions. The knowledge gained from this study helps resource professionals and landowners understand how cattle grazing affects forbs for pronghorn. This knowledge may be used to improve the suitability of pronghorn habitat through cattle grazing regimes.

In the mixed C₃/C₄ grassland of the southern Great Plains, United States, the invasive woody legume, honey mesquite (Prosopis glandulosa), affects grass production and composition differently beneath the canopy (subcanopy) than in spaces between trees (intercanopy) due in part to the dominant presence of C₃ Texas wintergrass (Nassella leucotricha) beneath the mesquite canopy and soil enrichment from N-fixation by mesquite. This arrangement, unlike most Prosopis systems worldwide that have C₄ grass or C₃ subshrub understories, uniquely affects grass production spatially and seasonally during mesquite expansion and possibly after anthropogenic removal of mesquite. We compared herbaceous and soil N responses in subcanopy and intercanopy microsites during the first 2 yr following a root-killing herbicide mesquite treatment. Perennial grass (PGR) and total herbaceous (THB) production were greater in treated than untreated intercanopy and subcanopy microsites at 1-yr post treatment, with Texas wintergrass comprising the largest portion of PGR. In yr 2, PGR production declined in both treated microsites with no differences between treatments. However, THB production remained greater in treated than untreated microsites due mainly to increased annual forb production that supplanted PGR production from yr 1. Increased annual forb production in treated microsites in yr 2 was likely due to high rainfall in the fall of yr 1 that stimulated forb seed germination, increased light from the loss of shading by mesquite, and soil inorganic N that increased from yr 1 to yr 2. Pretreatment spatial heterogeneity of herbaceous composition and soil N, caused by mesquite, affected post-treatment patterns of herbaceous production. The unexpected replacement of PGR by annual forbs in yr 2 revealed that grass forage production following brush control can deviate markedly from predicted models under certain conditions.

Bluebunch wheatgrass (BBWG; Pseudoroegneria spicata [Pursh] À. Löve) and Snake River wheatgrass (SRWG; Elymus wawawaiensis J. Carlson & Barkw.) are perennial cool-season grasses commonly used in rangeland restoration in the Intermountain West. The annual downy brome (Bromus tectorum L.) is widespread in the region, compromising perennial-grass establishment. We conducted two winter and one summer greenhouse target-neighbor trials to evaluate single-seedling performance of perennials grown with or without this annual grass neighbor (AGN). Our hypotheses were 1) an AGN impacts perennial wheatgrass seedlings' biomass and water-relations traits, 2) BBWG and SRWG differentially display traits when grown with and without an AGN, and 3) older wheatgrass cultivars differ from newer experimental populations for these traits. The AGN reduced shoot dry matter (DM) 28.2–33.1% and leaf area 32.5–35.9% across trials, but inconsistent differences for other traits suggested different drivers were operating among trials. In both winter trials, low humidity likely drove high vapor pressure deficits, leading to reduced water availability, with xylem pressure potential data suggesting greater water reduction in the third (winter) trial. In the second (summer) trial, heat rather than vapor pressure deficit was the likely driver. Both winter trials displayed higher shoot DM for BBWG under both AGN treatments, but in summer when the AGN was present, SRWG exceeded BBWG. In the summer trial, Goldar BBWG was sensitive to the combination of reduced water and heat. SRWG exhibited “faster” traits facilitating growth, while BBWG displayed “slower” traits conserving acquired resources. This may partially explain why SRWG's natural distribution is mostly restricted to rangelands with high soil fertility (e.g., the Palouse Prairie) while BBWG's distribution is more widespread. Newer experimental populations of both species often produced less shoot DM than older cultivars, suggesting the experimentals feature a more conservative growth strategy.

In the United States, the Bureau of Land Management (BLM) manages rangeland resources under dynamic conditions such as drought, annual grass invasion, and larger and more frequent wildfires. But federal policies governing rangelands are not structured to respond to annual variability or unexpected events. To integrate flexibility into public rangeland administration and potentially leverage fuels management treatments at the landscape scale, the BLM and livestock grazing permittees are exploring outcome-based rangeland management approaches to achieve desired ecological, social and economic conditions. This paper examines administrative policies and barriers to using outcome-based approaches to manage fire risk in Idaho through 70 semistructured interviews with permittees, BLM staff, and other agency and nongovernmental stakeholders in three Idaho BLM field areas. We analyzed how rules and norms in policy implementation contributed to perceptions of barriers within and among different field areas. Factors affecting perceptions of outcome-based rangeland management implementation included BLM staff tenure, permittee-agency relationships, beliefs about the efficacy of grazing to manage fire risk, and leadership and staff experience in navigating National Environmental Policy Act requirements or potential lawsuits. Differences in the informal institutions among field areas led to different interpretations of latitude found within formal institutions (“gray zones”) for implementation. This study highlights the importance of local context and the interactions between administrative policies and agency culture for implementing adaptive approaches to managing wildfire risk on public rangelands.

Rangeland production is a foundational ecosystem service and resource on which livestock, wildlife, and people depend. Capitalizing on recent advancements in the use of remote sensing data across rangelands, we provide estimates of herbaceous rangeland production from 1986 to 2019 at 16-d and annual time steps and 30-m resolution across the western United States. A factorial comparison of this dataset and three national scale datasets is presented, and we highlight a multiple-lines-of-evidence approach when using production estimates in decision making. Herbaceous aboveground biomass at this scale and resolution provides critical information applicable for management and decision making, particularly in the face of annual grass invasion and woody encroachment of rangeland systems. These readily available data remove analytical and technological barriers allowing immediate utilization for monitoring and management.

The process of community assembly is important to explain species coexistence and the maintenance of species diversity. Succession provides a good opportunity to study the role of the deterministic and stochastic processes during the community species composition. We investigated species composition and environmental factors and calculated the change in species diversity, phylogenetic diversity, net relatedness index, and nearest taxon index along a successional chronosequence, with a series of 0.5 × 0.5 m² plots (n = 20) from five successional subalpine meadow plant communities (ages 1, 3, 5, 15, and 30) in the Qinghai-Tibetan Plateau. In the plots, we found a significant change in species composition and abiotic environmental factors. Our redundancy analysis showed that soil nitrate nitrogen and soil organic carbon were the key environmental factors that affect the community composition in succession gradient. The community showed an overdispersion phylogenetic structure along with the early and medium succession. The ends of the succession stage showed a random or convergent phylogenetic structure. The results showed that the construction process of plant communities in the early and middle stages of succession was mainly affected by habitat filtering. In the late stage of succession, the process of community construction is more complex, which could be affected by the limiting similarity and neutral driving process. Our findings are important to be used in managing ecological restoration and protection.

Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis [Beetle & A. Young] S. L. Welsh) is a species of great concern due to its massive reduction in the past century. This species is challenging to incorporate into restoration projects due to its small seed and accompanying nonseed parts, which impedes flow and broadcast distance. In addition, seeding efforts commonly fail to produce plant densities that are sufficient to meet management objectives. Seed conglomeration is a novel technique that improves seed delivery and may also enhance plant establishment. We evaluated how seed conglomeration influences Wyoming big sagebrush plant emergence and establishment, for seed sown in the fall and winter, at five sites throughout Utah and Nevada. We found that seed conglomeration improved emergence by 60% and plant establishment by 26% in comparison with untreated seed. We estimate that this improvement in seeding success reduces the cost to produce established plants by 6%, which comes on top of a 55% savings provided by the technology through decreased time and labor required to sow the seed. We also found that the influence of planting season varied by site, with a fall planting outperforming a winter planting at two sites, a winter planting outperforming a fall planting at one site, and at the other two sites planting season had no effect. This finding is somewhat contrary to traditional seeding recommendations for Wyoming big sagebrush, which suggest seeding success will be higher with a winter planting. On the basis of these research results, further evaluations are merited to continue the development and assessment of seed conglomeration technology. Research should also continue to explore how planting date influences seeding success. Overall, this research does not provide strong justification for land managers to delay planting until winter and suggests they could be planting in the fall.