Society for Range Management Journal Archives: Recent submissions
Now showing items 21-40 of 10404
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Using the Rosgen Stream Classification System to Aid in Riparian Complex Ecological Site Descriptions DevelopmentLand managers need consistent terminology and classification frameworks to discuss the ecological status of the land. A common framework used in upland terrestrial systems is an ecological site description (ESD), in which systems are categorized by soils, vegetation, and topography. Creating ESDs in riparian areas must follow a different framework than upland systems because function of riparian systems is driven by hydrology. This study categorized riparian areas by hydrology using stream geomorphology and the Rosgen Stream Classification System. Stream cross sectional and longitudinal profile data were collected from 75 reaches from 19 streams in North Dakota from 2012 to 2018. Each reach (i.e., one full meander) was classified by channel type (E, C, B, F, and G), and stability class (stable and unstable). A stream parameter matrix was constructed using entrenchment ratio, width-to-depth ratio, sinuosity, slope, channel bed material, bank height ratio, and meander width ratio. A multiple response permutation procedure showed that the parameters differed on the basis of both channel type and stability class. An indicator analysis showed that entrenchment ratio, bank height ratio, and meander width ratio were the parameters most influential in separating the reaches by stability class. The strongest indicator stable reach was entrenchment ratio, but meander width ratio and bank height ratio were also significant indicators of stable and unstable reaches, respectively. The parameters used in this study to delineate channel type can be used to consistently discriminate between stable and unstable channels. This information may be a useful tool in describing the states and transitions of prairie stream development in riparian complex ESDs, validating the continued use of Rosgen Stream Classification System in ESD development. © 2019 The Society for Range Management
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US Sheep Industry and the Public Grazing FeeSince the mid-1940s US sheep inventory has experienced dramatic declines, which has weakened the sheep industry significantly, making it increasingly important to analyze potential policy implications that could affect US sheep inventories in the future. Public grazing lands are often used in sheep production, especially within the western United States. The public grazing fee is, therefore, a cost within the production of sheep. A US sheep model applying capital stock inventory accounting methodology is developed to model both the supply and demand within the joint sheep and wool industries. The model is used to create a baseline projection for the next several years. Various public grazing fee policies are created to demonstrate the effects of the policies on the levels of sheep inventory and sheep and wool production within the country. Results indicate removing the public grazing fee (set at $0/animal unit month) may slow the rate of decline but would not be effective at reversing the declining trend. This suggests reducing the public grazing fee is not a viable policy option to help bring stability to the sheep and wool industries. However, projections indicate raising the grazing fee would have a substantial adverse effect on the industries. Consideration should be given to these results as grazing fee policy is adjusted moving forward. © 2018 The Society for Range Management
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Unmanned Aerial Vehicle − Based Rangeland Monitoring: Examining a Century of Vegetation ChangesRangelands comprise a large component of the terrestrial land surface and provide critical ecosystem services, but they are degrading rapidly. Long-term rangeland monitoring with detailed, nonsubjective, quantitative observations can be expensive and difficult to maintain over time. Unmanned aerial vehicles (UAVs) provide an alternative means to gather unbiased and consistent datasets with similar details to field-based monitoring data. Comparing summer 2017 UAV images with long-term plot measurements, we demonstrate that rangeland vegetation cover changes can be accurately quantified and estimate an increase in total absolute shrub/subshrub cover from 34% in 1935 to > 80% in 2017 in central Arizona. We recommend UAV image-based rangeland monitoring for land managers interested in a few specific and dominant species, such as the foundation species, indicator species, or invasive species that require targeted monitoring. Land managers can identify and continuously monitor trends in rangeland condition, health, and degradation related to specific land use policies and management strategies. © 2019 The Author(s)
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Ungulate Herbivory Is Correlated with High Aspen Suckering Density but Reductions in Aspen Growth Rates and RecruitmentAspen is a foundation species that provides vital habitat for hundreds of plant and animal species. However, changing ungulate herbivory regimes may be altering recruitment success and resilience of aspen forests. The objective of this observational study was to quantify the impacts of ungulate herbivory on aspen recruitment potential. We sampled 36 aspen dominant stands on the Fishlake National Forest in Utah for browse of apical meristems, suckering density (< 180 cm in height), and recruitment density (≥ 180 cm). Our analysis indicated that for each 10% of apical meristems browsed, annual vertical and radial growth rates and recruitment density were reduced by 1.2 cm, 0.02 mm, and 17 ha− 1, respectively. In contrast, aspen suckering density increased by 1 230 suckers ha− 1, with each 10% browse of apical meristems. This suggests that ungulates contribute to aspen suckers persisting in the understory for longer periods and may alter recruitment success of aspen stands. Aspen that were under high ungulate browse pressure were associated with lower growth rates and persisted for twice as long in the understory. For example, a 5-yr-old sucker was predicted to be 115 cm without browse of apical meristems and 60 cm with 100% browse of apical meristems. Further, aspens of the same height with 100% browse of apical meristems were nearly 4 yr older on average than aspens with no evidence of browse of apical meristems. Approximately 34% of aspen suckers had persisted in the understory < 100 cm for ≥ 6 yr, and 7% of suckers had persisted in the understory for ≥ 10 yr. Our results suggest that high rates of meristem removal are correlated with increased aspen suckering yet reduced aspen growth and recruitment. © 2018 Elsevier Inc.
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Traditional Mobile Pastoralism in a Contemporary Semiarid Rangeland in Namaqualand, South AfricaPastoral systems are regarded as complex social-ecological systems with components that interact and change over a range of spatial and temporal scales. As such, herd mobility has traditionally been used to respond to the dynamic nature of these systems. However, mobile pastoral systems around the world are becoming more constrained and increasingly fragmented with important implications for herd mobility. This study assessed the spatial distribution of 256 herds and their mobility patterns over a decade in the 10 villages that comprise the spatially constrained Leliefontein pastoral area in South Africa. We developed a hierarchical model of rangeland use, which showed that several stratified and connected socioeconomic, climatic, and environmental factors determined the spatial and temporal use of grazing areas in this 192 000-ha semiarid environment. At the highest level of use, access to the Leliefontein pastoral area is formally regulated. At the next level, the place of residence of herd owners largely defined which village commons was used by their livestock. At the third level of rangeland use, the wealth status of owners determined where in relation to human settlements their herds were located. At the lowest level in the hierarchy, the locations of water and croplands delineated seasonal grazing areas and the movement of stockposts. These stratified factors, together with the overall variability in grazing resource availability and the different decision making processes involved, resulted in high flexibility and diversity of herd mobility patterns at the lowest level of rangeland use. This, in turn, ensured heterogeneity in resource use over a range of spatial and temporal scales. It was concluded that policies should embrace the complexity of the pastoral system and enable the adaptive management of herds. This could reduce the level of vulnerability experienced by pastoralists to climate variability and wider societal change. © 2018 The Society for Range Management
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To Insure or not to Insure? Factors Affecting Acquisition of Prescribed Burning Insurance CoveragePrescribed burning is a widely used tool in forest and grassland management. However, because fire that escapes from a prescribed burn accidentally may cause property damage, injuries, and even human casualties, purchasing insurance to cover such damages may be beneficial for prescribed burn practitioners. Given that insurance coverage for prescribed fire is recently emerging, factors that determine burners’ decisions to purchase such insurance are largely unknown. On the basis of data from a survey of prescribed burn practitioners in 14 southern and midwestern states, we modeled prescribed burners’ likelihood of purchasing insurance with respect to demographic characteristics, land management objectives, and importance placed on regulatory compliance and land use practices. Results suggest that prescribed burn practitioners are more likely to obtain such insurance if they are landowners themselves or have a written prescribed burn plan. Age of respondents and the level of importance they place on compliance with environmental laws also had a significant positive effect on the likelihood of obtaining insurance coverage. Respondents were less likely to purchase insurance if their land management objective was to control invasive plants or they considered the availability of lower-cost alternatives for woody plant removal an important factor in deciding whether or not to conduct prescribed burns. These findings shed light on underlying factors influencing insurance coverage for prescribed burning and are potentially beneficial for promoting the acquisition of insurance among burn practitioners. © 2019 The Society for Range Management
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The Classification of Grassland Types Based on Object-Based Image Analysis with Multisource DataThe spatial distribution of different grassland types is important for effectively analyzing spatial patterns, obtaining key vegetation parameters using remote sensing (e.g., biomass, leaf area index, net primary production), and using and protecting grasslands. Existing classifications of grasslands by remote sensing are mostly divided according to the fractional vegetation cover or biomass, but classifications according to grassland types are scarce. In this study, we focused on the classification of different grassland types using remote sensing based on object-based image analysis (OBIA) with multitemporal images in combination with a 30-m digital elevation model (DEM) and the normalized difference vegetation index (NDVI). The grasslands were located in Hulunber, Inner Mongolia, and an autonomous region of China. The support vector machine (SVM) and random forest (RF) machine learning classifiers were selected for the classification. The results revealed the following: 1) It is feasible to generally extract different grassland types on the basis of OBIA with multisource data; the overall classification accuracy and Kappa value exceeded 90% and 0.9, respectively, using the SVM and RF machine learning classifiers, and the classification accuracy of the different grassland types ranged from 61.64% to 98.71%; 2) Multitemporal images and auxiliary data (DEM and NDVI) improved the separability of different grassland types. The information in the growing season was conducive for distinguishing temperate meadow steppe from temperate steppe and was favorable for extracting lowland meadow and swamp in the nongrowing season. The DEM and NDVI also effectively reduced the number of image segmentation objects and improved the segmentation effects; 3) Spectral and textural features were more important than geometric features in this study. A few main variables played a major role in the classification, while a large number of variables had either no significant effect or a negative effect on the classification results when the optimal feature subset was determined. This study provides a scientific basis and reference for the classification of various grassland types by remote sensing, including the data selection, image segmentation, feature selection, classifier selection, and parameter settings. © 2018 The Society for Range Management
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Technical Note: Method to Streamline Processing of Livestock Global Positioning System Collar DataThe use of global positioning system (GPS) technology to study livestock movement has been widely adopted in range and animal sciences; however, the methods for processing GPS collar data are varied among researchers and often involve repetitive, time-consuming steps to get data into a format available to view in geographic information system (GIS) software. The objective of this technical note is to present a method for quickly processing uniform datasets using a commonly available commercial GPS collar and Program R. Data generated by a Lotek 3300LR GPS collar were processed in seconds using “Lotek_Function,” which was developed using R coding. Traditional hand-processing of the same data generally requires 30 or more minutes and is prone to error due to the tedious, repetitive nature of the task. Due to the open-source nature of Program R, base codes can be modified to fit specific researchers’ needs when incorporating GIS data layers or models to assess behavior based on motion sensor data output from collars. © 2019 The Society for Range Management
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Targeted Grazing for Native Forbs in Annual GrasslandsTargeted grazing is a promising strategy for addressing management issues in annual grasslands. We evaluated targeted cattle grazing strategies for tarweed (Hemizonia fitchii A. Gray) and vinegarweed (Trichostema lanceolatum Benth.). These native annual forbs provide biodiversity to annual grass-dominated landscapes, in addition to being important pollinator plants that discourage yellow starthistle (Centaurea solstitialis L.) invasion. However, these forbs can form dense stands that interfere with grazing. Therefore, we sought grazing strategies that promote sparse stands to maintain livestock production while supporting other ecosystem services. Treatments were 1) early grazing when dominant annual grasses were vegetative, 2) late grazing when grasses were senescing, 3) repeated grazing, and 4) a nongrazed control. These treatments were applied in 2011, 2012, and 2013. In 2012, neither tarweed nor vinegarweed were observed regardless of treatment, likely due to low water availability during their major growth period. In 2011 and 2013, grazing grasses repeatedly throughout the growing season increased tarweed to 3 − 5 plants m− 2, compared with < 1 plants m− 2 in the control, and in 2011 repeated grazing also increased vinegarweed. Therefore, although environmental factors can prevent tarweed and vinegarweed from forming stands some years, defoliating grasses repeatedly from vegetative through senesced stages is the most reliable way to encourage these forbs in annual grasslands. However, a single period of defoliation can also encourage tarweed: In 2011 and 2013, we found a single period of grazing as annual grasses senesced and tarweed began rapid growth increased tarweed, possibly by increasing light availability. Finally, we found grazing once early in the growing season provided low tarweed and vinegarweed densities, likely because the long postgrazing period allowed annual grasses to recover and competitively suppress these forbs. Therefore, early grazing may reduce/prevent overly dense tarweed and vinegarweed stands. © 2019 The Society for Range Management
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Synthesis Paper: Targeted Livestock Grazing: Prescription for Healthy RangelandsTargeted livestock grazing is a proven tool for manipulating rangeland vegetation, and current knowledge about targeted livestock grazing is extensive and expanding rapidly. Targeted grazing prescriptions optimize the timing, frequency, intensity, and selectivity of grazing (or browsing) in combinations that purposely exert grazing/browsing pressure on specific plant species or portions of the landscape. Targeted grazing differs from traditional grazing management in that the goal of targeted grazing is to apply defoliation or trampling to achieve specific vegetation management objectives, whereas the goal of traditional livestock grazing management is generally the production of livestock commodities. A shared aim of targeted livestock grazing and traditional grazing management is to sustain healthy soils, flora, fauna, and water resources that, in turn, can sustain natural ecological processes (e.g., nutrient cycle, water cycle, energy flow). Targeted grazing prescriptions integrate knowledge of plant ecology, livestock nutrition, and livestock foraging behavior. Livestock can be focused on target areas through fencing, herding, or supplement placement. Although practices can be developed to minimize the impact of toxins contained in target plants, the welfare of the animals used in targeted grazing must be a priority. Monitoring is needed to determine if targeted grazing is successful and to refine techniques to improve efficacy and efficiency. Examples of previous research studies and approaches are presented to highlight the ecological benefits that can be achieved when targeted grazing is applied properly. These cases include ways to suppress invasive plants and ways to enhance wildlife habitat and biodiversity. Future research should address the potential to select more adapted and effective livestock for targeted grazing and the associated animal welfare concerns with this practice. Targeted livestock grazing provides land managers a viable alternative to mechanical, chemical, and prescribed fire treatments to manipulate rangeland vegetation. © 2019 The Authors
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Sustainable Rangeland Management in Southwest Iran: Understanding Changes in Experts’ Attitudes Toward Livelihood AlternativesThe importance of knowledge sharing, as an integral part of decision making, has been highly acknowledged by many authors. However, the process in which knowledge sharing should be conducted has remained a debatable issue. In this study, changes in experts’ attitudes, as a result of the knowledge-sharing process, in the context of rangeland management were assessed. We demonstrated a three-step knowledge-sharing process while recognizing collaborative knowledge sharing systems, which involves knowledge-sharing tools including face-to-face and virtual approaches. The process was applied to explore experts’ attitudes regarding livelihood alternatives in the Bazoft region of southwestern Iran. Sixty experts were selected from three groups categorized as key local stakeholders, practitioners, and scientists. First, the experts were independently given the task of ranking livelihood alternatives. Next, for a better understanding of alternatives and enhancing their view, additional knowledge and information were provided. Thereafter, their attitudes in the final step were assessed. According to the findings, change in the experts’ attitudes could take place, which eventually resulted in the prioritization of livelihood alternatives to approach sustainable rangeland management (SRM). The synergy of experts’ knowledge, which can be realized through a collaborative knowledge sharing process, can be further pursued by devising a workable policy framework to approach SRM. © 2019 The Society for Range Management
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Statewide Cross-Sectional Survey of Cryptosporidium and Giardia in California Cow-Calf HerdsCryptosporidium spp. and Giardia duodenalis are common protozoal parasites in livestock including beef cattle on rangeland and irrigated pasture. A statewide cross-sectional study was conducted to determine the prevalence, species or genotype, and risk factors for fecal shedding of Cryptosporidium and Giardia by cattle from California cow-calf operations. Species and genotypes of Cryptosporidium and Giardia were determined by molecular fingerprinting. Prevalence of Cryptosporidium (19.8%) and Giardia (41.7%) in fecal samples from calves were approximately twice as high as fecal samples from cows (9.2% and 23.1%, respectively). In addition to age, multivariable logistic regression showed that higher stocking density and a higher number of replacement heifers were positively associated with fecal shedding of Cryptosporidium while longer calving interval, a winter/spring calving season, and higher numbers of replacement heifers were positively associated with shedding of Giardia. The dominant species and genotypes of Cryptosporidium and Giardia in feces from these cow-calf herds were Cryptosporidium ryanae (75%) and assemblage E for Giardia duodenalis (90%), which have low impact on public health compared with other zoonotic species/genotypes of these two parasites. We identified host and potential management practices that can be used to protect cattle health and reduce the risk of surface water contamination with protozoal parasites from cow-calf operations. In addition, this work updated the scientific data regarding the predominance of low zoonotic genotypes of Cryptosporidium and Giardia shed in the feces of commercial cow-calf herds on California rangeland and irrigated pasture. © 2019 The Society for Range Management
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Stand Dynamics of Pinyon-Juniper Woodlands After Hazardous Fuels Reduction Treatments in ArizonaPinyon-juniper ecosystems occur extensively across western North America, and at the landscape scale, variation in structure and composition is influenced by topographic position, soils, disturbance history, and local climate. The persistent pinyon-juniper woodland is a common structural form, and though they are known to be infrequent-fire systems, there is increasing interest in implementation of hazardous fuels reduction treatments in woodlands, especially in the wildland-urban interface. Few studies have quantified stand dynamics following fuels reduction treatments in persistent woodlands or compared treatment outcomes to conditions that develop under natural disturbance and successional processes. In 2004, we established a randomized, replicated study in woodlands of northern Arizona, and monitored stand dynamics and understory responses to determine how stand-level changes differed between common fuels reduction approaches. We compared the resulting structure with a conceptual state-and-transition model. Results showed that, over the 11 yr after treatment, juniper tree densities decreased by 8.4% and 0.9% but increased by 14.0% and 27.3% in Control, Burn, Thin, and Thin + Burn treatments, respectively. Pinyon tree densities decreased by 1.1% and 3.3%, increased by 12.2%, and decreased 7.9% in Control, Burn, Thin, and Thin + Burn treatments, respectively. All treatments showed fuel load reductions throughout the 11-yr study period and minimal rebound of tree recruitment toward pretreatment conditions. Prescribed fire alone (Burn) maintained persistent woodland conditions. Thinning treatments substantially reduced small tree densities and, with the addition of prescribed fire, produced losses of large trees. Thinning with prescribed fire (Thin + Burn) tended to produce conditions qualitatively unlike those described by our state-and-transition model. Evaluation of these commonly used fuels treatments against our state-and-transition model suggested that concerns regarding loss of ecological integrity may be warranted. © 2019 The Society for Range Management
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Soil Fauna Accelerate Dung Pat Decomposition and Nutrient Cycling into Grassland SoilSoil fauna play critical roles in various ecosystem functions and services, but empirical data measuring their impact on dung pat decomposition and subsequent nutrient cycling into rangeland soils are limited. The objective of this study was to quantify the effect of soil fauna, using dung beetle as an indicator, on dung decomposition and subsequent translocation of dung nutrients into grassland soil over time. A field experiment was conducted early in the summer season and late in the summer season of 2014 and 2015. In each season, dung beetle abundance, changes in dung properties, and subsequent translocation of dung nutrients into soils were evaluated at 1, 3, 7, 14, 28, and 56 d after placement (DAPs) of exposed dung and nonexposed dung to beetles. Analysis of no-dung control soil was included for comparison. Dung beetles contributed 7% and 4% in the losses of dung moisture and dry matter (DM), respectively; however, dung beetles had no effect on dung pat nutrients. Losses of dung nutrients—42% of water-extractable organic carbon, 46% of water-extractable phosphorus, and 65% of NH4—occurred during the first 14 DAPs. Dung beetles increased soil nutrients in the top 10-cm depth beneath the dung. No effect of beetles was observed in deeper (> 10-cm) soil depth or in soil 30 cm away from the dung. This study concluded that soil fauna, such as dung beetles, accelerated dung moisture and DM losses and subsequent nutrient increase into the top 10 cm of soil. © 2019
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Simulating Rangeland Ecosystems with G-Range: Model Description and Evaluation at Global and Site ScalesRangeland ecosystems and their roles in providing ecosystem services are vulnerable to changes in climate, CO2 concentration, and management. These drivers forcing widespread changes in rangeland ecosystem processes and vegetation dynamics create two-way interactions and feedback loops between biogeochemistry and vegetation composition. To support spatial simulation and forecasting in the global rangelands, the G-Range global rangelands model couples biogeochemical submodels from the CENTURY soil organic matter model with dynamic populations’ submodels for herbs, shrubs, and trees. Here is presented a model description for G-Range, including novel elements of G-Range and implementation of CENTURY code. An initial evaluation of G-Range at global and site scales follows. G-Range outputs for net primary productivity (NPP) and vegetation cover (herbs, shrubs, trees, bare ground) were evaluated against global MODIS layers at global and site scales, and aboveground and belowground NPP were compared with field data from globally distributed sites. Most model outputs evaluated were within the range of a priori benchmarks for tolerable absolute or relative error (two benchmarks per output, at two scales, for five outputs of NPP and vegetation cover). Trade-offs in model fit among variables, datasets, and scales indicated practical constraints on improving model fit with respect to the selected evaluation datasets, especially field NPP versus MODIS NPP. The relative effects of multiple drivers of rangeland vegetation change were the greatest sources of uncertainty in model outputs. G-Range is best suited to scenario analysis of large-scale and long-term impacts of climate, CO2, and management on rangeland ecosystem processes and vegetation, as well as ecosystem services, such as production of forage and browse and carbon sequestration. © 2019 The Authors
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Socioecological Determinants of Drought Impacts and Coping Strategies for Ranching Operations in the Great PlainsIn Great Plains rangelands, drought is a recurring disturbance. Ranchers in this region expect to encounter drought but may not be adequately prepared for it. Efforts to encourage drought preparedness would benefit from a better understanding of the conditions under which managers make decisions to minimize the impacts of drought. We tested the direct and moderating roles of the drought hazard and the social-ecological context on drought impacts and response. This study was conducted with ranchers in western and central South Dakota and Nebraska following the drought that began in 2012. We surveyed ranchers regarding the effects of the drought and their responses and used multimodel analysis to explore the relationships among measures of drought preparedness, drought response, and drought impacts. Drought severity was the primary predictor of all impacts, but specific types of impacts were varied depending on the operation's enterprise mix, resources, and management. The socioecological characteristics of the ranch system predicted drought response actions taken, by either providing the necessary resources and capacity to take action or creating sensitivity in the system that required action to be taken. We conclude with recommendations for learning from current drought experiences in order to better adapt to future drought events. © 2019 The Society for Range Management
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Short-Term Response of Two Beneficial Invertebrate Groups to Wildfire in an Arid Grassland System, United StatesRangeland invertebrates contribute greatly to biodiversity and provide important services including pollination, pest control, and nutrient cycling. As wildfire frequency increases across these areas of the United States, it is imperative to understand how these disturbances affect beneficial invertebrate communities. We examined bee (Hymenoptera), spider (Araneae), and vegetative communities 1 yr before and 1 yr after a large wildfire swept across an intact grassland in eastern Oregon. Several sites were left unburned after the fire, and a before-after-control-impact study design was used to assess changes within the communities. Fire had no effect on bee or spider abundance, or spider diversity or richness; however, fire significantly increased native bee diversity and richness. In addition, composition of both native bee and spider communities differed significantly between burned and unburned areas 1 yr after the fire. Sheet web spiders (Linyphiidae) and several bee species (primarily large, generalist species) were associated with burned sites. Invasive annual grass and biological soil crust cover decreased significantly in burned sites, but maximum vegetation height and litter cover did not differ significantly among treatments. Forb abundance increased in burned sites; however, species richness of forbs in burned and unburned sites did not differ significantly 1 yr after the fire. Several forbs were indicative of burned areas including non-native species, such as Douglas’ knotweed (Polygonum douglasii) and Russian thistle (Salsola tragus), and native species such as Canadian horseweed (Conyza canadensis), hoary tansyaster (Machaeranthera canescens), and tall willowherb (Epilobium brachycarpum). This study demonstrates that both invertebrate and plant communities show strong short-term responses to wildfire, and our results can be used to inform management of rare habitat and biodiversity in rangelands impacted by wildfire in arid grasslands. © 2018 The Society for Range Management
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Shifting Cattle Producer Beliefs on Stocking and Invasive Forage: Implications for Grassland ConservationTo advance the dialogue to define sustainable working landscapes, it is essential to include the perceptions, knowledge, and factors guiding decision making. We surveyed livestock producers in the Grand River Grasslands region of southern Iowa and northern Missouri, United States, to gain insight into key factors shaping decision making and perspectives on effective management practices in the eastern Great Plains, focusing in particular on demographic and social change and producer willingness to reduce stocking rate as a conservation practice. First, a longitudinal evaluation of livestock producer demographics in 2007 and 2017 revealed individuals were older and were renting grazing land to a greater extent than in 2007. Second, when making land management decisions, producers in 2017 focused on economic concerns more than environmental concerns compared with more balanced views in 2007. For those who prioritized the environment over economics, this prioritization was related to both higher levels of education and a willingness to reduce stocking rate (livestock production) if there is a positive conservation outcome. In contrast, a lower willingness to reduce stocking was associated with increasing rental acreage and prevalence of an invasive cool-season grass that responds favorably to heavy grazing (tall fescue, Schedonorus arundinaceus Schreb.). Regardless, about 37% of cattle producers representing ∼ 40% of the land area surveyed were at least moderately willing to reduce stocking rates to achieve a conservation outcome. In conclusion, our findings suggest that producers’ need to gain income from livestock may limit the willingness to enact a conservation practice similar to reduced stocking rates. However, there is clearly conservation receptiveness from a segment of the producer community, which indicates potential for improved conservation. © 2019 The Society for Range Management
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Short-Term Control of an Invasive C4 Grass With Late-Summer FireYellow bluestem (Bothriochloa ischaemum [L.] Keng var. songarica [Rupr. ex Fisch & C.A. Mey] Celarier & Harlan) is a non-native, invasive C4 grass common in southern Great Plains rangelands. We measured the effects of a single late-summer (September 2006) fire on yellow bluestem at two sites in central Texas (Fort Hood and Onion Creek). At Fort Hood, relative frequency of yellow bluestem in burned plots decreased from 74 ± 4% (preburn; mean ± standard error) to 9 ± 2% (2007) and remained significantly lower compared with unburned plots through 2009 (burned: 14 ± 2%; unburned: 70 ± 14%). At Onion Creek, yellow bluestem initially decreased from 74 ± 5% (2006) to 32 ± 7% (2007). Yellow bluestem recovered substantially by 2009 (67 ± 10%) but was still significantly lower than in unburned transects (96 ± 1%). Relative frequency of other graminoids increased significantly in burned plots (compared with preburn values) at Fort Hood (preburn: 11 ± 4%; 2009: 29 ± 7%) but not at Onion Creek (preburn: 24 ± 6%; 2009: 22 ± 7%). Frequency of forbs increased dramatically in the first growing season after fire (Fort Hood: 15 ± 2% to 76 ± 3%; Onion Creek: 2 ± 2% to 45 ± 5%), then decreased through the third growing season (Fort Hood: 57 ± 6%; Onion Creek: 11 ± 4%). Key differences between the sites include much higher biomass at Fort Hood than at Onion Creek (8 130 kg · ha-1 vs. 2 873 kg · ha-1), more recent grazing at Onion Creek (ending in 2000 vs. before 1996 at Fort Hood), and higher rainfall after the Onion Creek burn (214 mm in 20 days vs. 14 mm). Late-summer fire can temporarily decrease yellow bluestem frequency, but effects vary with site conditions and precipitation. Restoring dominance by native grasses may require additional management.
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Seasonal Divergence of Landscape Use by Heritage and Conventional Cattle on Desert RangelandAdopting livestock with heritage genetics may help to improve the sustainability of agriculture on rangelands with harsh, challenging conditions. In the Chihuahuan Desert, preliminary evidence suggests that heritage Raramuri Criollo exploit a greater variety of range resources than do conventional cattle. Accordingly, the use of Raramuri Criollo may help sustain vegetation and soils, as well as agricultural production. To explore these possibilities, we used Global Positioning System collars to track Angus × Hereford and Raramuri Criollo cows in a 1 535-ha pasture in southern New Mexico in June–December 2008. As predicted on the basis of past research, home range sizes of Raramuri Criollo exceeded those of Angus × Hereford during seasons with low forage availability—by 31.4 ± 6.5 ha during Pregreenup and 17.2 ± 6.5 ha during Drydown—but sizes converged during more productive seasons (Greenup 1, Greenup 2). Angus × Hereford allotted more daily time to resting, with the difference most pronounced during Drydown (71.1 ± 21.1 min day− 1). Angus × Hereford had twice as many hotspots of use (locations with multiple visits of long duration), with seasonal timing and location corresponding with distribution patterns known to impact desirable natural resources. Raramuri Criollo more strongly preferred the Bare/Forbs ecological state with seasonal timing that possibly signals an ability to use nutritious forbs on open ground despite summer heat. Results are consistent with conjectures that compared with conventional cattle, Raramuri Criollo have greater daily mobility and wider spatial distribution during dry seasons. Although not directly measured, results also suggest that the heritage breed has superior heat tolerance and lower impact on desirable natural resources. These findings provide evidence that Raramuri Criollo can support sustainable livestock production in the Chihuahuan Desert, but direct measurements of profitability and environmental effects are needed before adoption can be recommended widely. © 2019 The Society for Range Management