ABOUT THE COLLECTIONS

Welcome to the Rangeland Ecology & Management archives. The journal Rangeland Ecology & Management (RE&M; v58, 2005-present) is the successor to the Journal of Range Management (JRM; v. 1-57, 1948-2004.) The archives provide public access, in a "rolling window" agreement with the Society for Range Management, to both titles (JRM and RE&M), from v.1 up to five years from the present year.

The most recent years of RE&M are available through membership in the Society for Range Management (SRM). Membership in SRM is a means to access current information and dialogue on rangeland management.

Your institution may also have access to current issues through library or institutional subscriptions.

Print ISSN: 0022-409x

Online ISSN: 1550-7424

QUESTIONS?

Contact the University Libraries Journal Team with questions about these journals.

Recent Submissions

  • Rangeland Ecology & Management Table of Contents Volume 72, Number 3 (2019)

    Society for Range Management (Elsevier Inc., 2019-05)
  • Rangeland Ecology & Management Editorial Board Volume 72, Number 3 (2019)

    Society for Range Management (Elsevier Inc., 2019-05)
  • Variation in Surrogate Breeding Habitat Quality Between Continuously Grazed Rangelands and Late-Cut Hayfields for a Threatened Grassland Birds

    Pintaric, A.L.; Reid, R.; Nol, E. (Elsevier Inc., 2019-05)
    Rangelands and hayfields provide a large portion of remaining surrogate habitat for many species of declining grassland birds in North America. We compared late-cut hayfields and continuously grazed pastures at low to moderate cattle densities for providing suitable breeding habitat in eastern Canada for the nationally threatened Bobolink (Dolichonyx oryzivorus). To examine the quality of both habitats, we conducted point counts and monitored 87 nests during the 2015 and 2016 breeding seasons. Bobolink abundance and daily survival rate (DSR) of nests were modeled sequentially by habitat and sex as a function of vegetation structure, prey availability, and agricultural management. Year and habitat were the strongest predictors of abundance. When analyzed separately for pastures and hayfields, vegetation height was most important for female abundance in pastures while pasture size was most important for males. Nests in hayfields had significantly higher daily survival (DSR = 0.98 ± 0.01) than nests in pastures (DSR = 0.94 ± 0.01). Nesting success was highest in hayfields with taller vegetation, while in pastures, no microhabitat variable showed a clear relationship with DSR. Within pastures, cattle stocking densities of ≤ 1 animal units (AU) · ha− 1 were not related to DSR. This study provides evidence that late-cut hay is of highest quality, but that small-scale beef farms with low to moderate stocking densities are suitable targets for conservation efforts of Bobolinks in eastern North America. © 2019 The Society for Range Management
  • US Sheep Industry and the Public Grazing Fee

    Feuz, R.; Kim, M.-K. (Elsevier Inc., 2019-05)
    Since 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
  • Ungulate Herbivory Is Correlated with High Aspen Suckering Density but Reductions in Aspen Growth Rates and Recruitment

    Rhodes, A.C.; Fitch, C.; St., Clair, S.B. (Elsevier Inc., 2019-05)
    Aspen 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.
  • Targeted Grazing for Native Forbs in Annual Grasslands

    Davy, J.S.; Rinella, M.J. (Elsevier Inc., 2019-05)
    Targeted 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
  • Sustainable Rangeland Management in Southwest Iran: Understanding Changes in Experts’ Attitudes Toward Livelihood Alternatives

    Khedrigharibvand, H.; Azadi, H.; Teklemariam, D.; Ebrahimi, A.; Omidzadeh, Ardali, E.; Van, Acker, V.; Van, Eetvelde, V.; De, Maeyer, P.; Witlox, F. (Elsevier Inc., 2019-05)
    The 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
  • Statewide Cross-Sectional Survey of Cryptosporidium and Giardia in California Cow-Calf Herds

    Li, X.; Flores, K.A.; Barry, S.; Becchetti, T.A.; Doran, M.; Finzel, J.A.; Larsen, R.; Lile, D.; McDougald, N.; Nguyen, T.; et al. (Elsevier Inc., 2019-05)
    Cryptosporidium 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
  • Socioecological Determinants of Drought Impacts and Coping Strategies for Ranching Operations in the Great Plains

    Haigh, T.R.; Schacht, W.; Knutson, C.L.; Smart, A.J.; Volesky, J.; Allen, C.; Hayes, M.; Burbach, M. (Elsevier Inc., 2019-05)
    In 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
  • Short-Term Response of Two Beneficial Invertebrate Groups to Wildfire in an Arid Grassland System, United States

    Smith, DiCarlo, L.A.; DeBano, S.J.; Burrows, S. (Elsevier Inc., 2019-05)
    Rangeland 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
  • Patterns of Big Sagebrush Plant Community Composition and Stand Structure in the Western United States

    Pennington, V.E.; Bradford, J.B.; Palmquist, K.A.; Renne, R.R.; Lauenroth, W.K. (Elsevier Inc., 2019-05)
    Big sagebrush (Artemisia tridentata Nutt.) plant communities are found in western North America and comprise a mix of shrubs, forbs, and grasses. Climate, topography, and soil water availability are important factors that shape big sagebrush stand structure and plant community composition; however, most studies have focused on understanding these relationships at sites in a small portion of the big sagebrush region. Our goal was to characterize detailed stand structure and plant composition patterns and identify environmental variables related to those patterns by sampling 15 sites distributed across the western United States. In each site, we characterized stand structure at the individual shrub level and at the site level. We quantified size distributions and assessed relationships among canopy volume, age, and height. We also characterized functional type cover and species composition and related those to climatic, topographic, and edaphic variables. Mean big sagebrush age ranged from 21 (± 8) to 57 (± 22) yr at individual sites, mean height ranged from 0.23 (± 0.12) to 0.67 (± 0.23) m, and mean canopy volume ranged from 0.03 (± 0.04) to 0.62 (± 0.51) m3. Bare ground and litter contributed the most cover (mean = 64%), followed by big sagebrush (mean = 39% of vascular plant cover). There was a negative relationship between big sagebrush cover and grass and forb cover. Species composition was related to both climate and elevation, likely because these variables influence water availability. Although our study was limited to 15 field sites, our detailed descriptions of widely distributed sites provide insight into the magnitude of variability in big sagebrush plant community structure. © 2018 The Society for Range Management
  • Northern Bobwhite (Colinus virginianus) Space Use Minimally Affected by Oil and Gas Development

    Duquette, C.A.; Davis, C.A.; Fuhlendorf, S.D.; Elmore, R.D. (Elsevier Inc., 2019-05)
    Despite the fact that the northern bobwhite (Colinus virginianus Linnaeus; hereafter, bobwhite) is one of the most well-studied and widely distributed wildlife species in North America, we know little about how bobwhite respond to oil and gas infrastructure. We investigated the impacts of oil and gas development on space use of bobwhite using a multiseason approach. We captured and monitored bobwhite in the breeding season (1 April–30 September, n = 135 individuals) and nonbreeding season (1 October–31 March, n = 30 coveys) and modeled their habitat selection in a resource-utilization function (third order, within home range selection) and resource-selection function (second order, home range selection) format. Generally, energy infrastructure effects on bobwhite were neutral, but breeding season bobwhite did select for areas near low-traffic roads (β = − 0.31 ± 0.15 SE). In the nonbreeding season, coveys selected for areas within their home range with a limited viewshed (i.e., areas with limited visibility of anthropogenic structures; β = − 0.03 ± 0.02 SE). Selection differed between sexes for well pads (t = − 2.12, P = 0.04) but was otherwise similar. At the level of home range selection, bobwhite exhibited a preference for areas with a low density of oil and gas wells and a high density of low-traffic roads during both the breeding and nonbreeding seasons (breeding: βwell = − 0.14 ± 0.02, βroad = 0.26 ± 0.27; nonbreeding: βwell = − 0.08 ± 0.03, βroad = 0.16 ± 0.03). As a generalist species, bobwhite appear to be largely tolerant of energy infrastructure and associated disturbances at moderate levels of development but may be sensitive to high densities of oil and gas pads. © 2018 The Society for Range Management
  • On Conflict and Conflict of Interest

    Karl, J.W.; Sheley, R.; Levi, E.; Brown, J. (Elsevier Inc., 2019-05)
  • Nondestructive Age Estimation of Mountain Big Sagebrush (Artemisia tridentata ssp. vaseyana) Using Morphological Characteristics

    Landeen, M.L.; Kitchen, S.G.; Allphin, L.; Petersen, S.L. (Elsevier Inc., 2019-05)
    Current methods for determining plant age of shrub species require destructive sampling and annual growth ring analysis on the primary stem. Although individual plant ages can frequently be determined in this manner, the method is time consuming and of limited value for plants that have lost stem wood from stem splitting and rot. Nondestructive methods for estimating big sagebrush (Artemisia tridentata Nutt.) plant age would be useful in assessing stand age structure and population dynamics at variable spatial scales. The purpose of this study was to test a suite of traits for potential use in estimating mountain big sagebrush (Artemisia tridentata ssp. vaseyana [Rydb.] Beetle) age. We evaluated traits including plant height, crown area, subcanopy litter depth, percent crown mortality, bark furrow depth, bark fiber length, circumference and diameter of plant basal stem, and circumference of secondary and tertiary branches. We measured and harvested basal cross-sections from 163 plants of varying sizes from five locations in central and south-central Utah. Plant age was determined from annual growth rings. Linear regression analyses revealed that stem diameter (r2 = 0.507 P < 0.0001) was the most highly correlated variable with plant age across all sites, followed by stem circumference (r2 = 0.474 P < 0.0001), secondary branch circumference (r2 = 0.360, P < 0.0001), tertiary branch circumference (r2 = 0.405, P < 0.0001), and bark fiber length (r2 = 0.373, P < 0.0001). Results support previous findings that stem girth has value for estimating mountain big sagebrush plant age and that this trait is a better indicator of age than any other tested traits. Although the relationship between stem diameter and plant age was significant, substantial stem size variability associated with plants of the same approximate age indicates that the method is most appropriate when precise age estimates are not required. This technique was developed specifically for mountain big sagebrush, but it is expected that it can be adapted for other sagebrush taxa. © 2019 The Society for Range Management
  • Liability and Prescribed Fire: Perception and Reality

    Weir, J.R.; Kreuter, U.P.; Wonkka, C.L.; Twidwell, D.; Stroman, D.A.; Russell, M.; Taylor, C.A. (Elsevier Inc., 2019-05)
    Changing climate and fuel accumulation are increasing wildfire risks across the western United States. This has led to calls for fire management reform, including the systematic use of prescribed fire. Although use of prescribed fire by private landowners in the southern Great Plains has increased during the past 30 yr, studies have determined that liability concerns are a major reason why many landowners do not use or promote the use of prescribed fire. Generally, perceptions of prescribed fire − related liability are based on concerns over legal repercussions for escaped fire. This paper reviews the history and current legal liability standards used in the United States for prescribed fire, it examines how perceived and acceptable risk decisions about engagement in prescribed burning and other activities differ, and it presents unanticipated outcomes in two cases of prescribed fire insurance aimed at promoting the use of prescribed fire. We demonstrate that the empirical risk of liability from escaped fires is minimal (< 1%) and that other underlying factors may be leading to landowners’ exaggerated concerns of risk of liability when applying prescribed fire. We conclude that providing liability insurance may not be the most effective approach for increasing the use of prescribed fire by private landowners. Clearly differentiating the risks of applying prescribed fire from those of catastrophic wildfire damages, changing state statutes to reduce legal liability for escaped fire, and expanding landowner membership in prescribed burn associations may be more effective alternatives for attaining this goal. Fear of liability is a major deterrent to the use of prescribed fire; however, an evaluation of the risks from escaped fire does not support perceptions that using prescribed fire as a land management tool is risky. Prescribed burning associations and agencies that support land management improvement have an important role to play in spreading this message. © 2018 The Society for Range Management
  • Influences of Groundwater and Climatic Factors on Grassland in Xiliao River Plain, Northern China

    Jin, X.; Chen, M.; Fan, Y.; Duan, H.; Yan, L. (Elsevier Inc., 2019-05)
    Grassland is an important natural resource in the Xiliao River Plain, Northern China because of its ecological and economic importance. The overexploitation of groundwater makes it necessary to understand the influence of groundwater decline on grassland vegetation growth in this region, especially in the context of climatic change. We aimed to identify the main factor affecting the grassland growth through integrated analysis of grassland impact factors. Changes in normalized difference vegetation index, groundwater depth, precipitation, and temperature were analyzed during 1982 − 2013 in Xiliao River Plain. A correlation analysis was conducted among groundwater depth, precipitation, temperature, and normalized difference vegetation index using Pearson correlation equations. Results indicated that precipitation became the main influencing factor of grassland growth instead of groundwater depth due to the increase of groundwater depth after 1999. This shift might pose a threat to the survival of grassland growth during a long drought period. Therefore, groundwater change issues should be gradually integrated into future policies and strategies for grassland development and management. © 2018
  • Horse Activity is Associated with Degraded Subalpine Grassland Structure and Reduced Habitat for a Threatened Rodent

    Eldridge, D.J.; Travers, S.K.; Val, J.; Zaja, A.; Veblen, K.E. (Elsevier Inc., 2019-05)
    Feral (wild) horses present significant challenges for landscape managers. A major effect of horses is trampling, which erodes soil and alters vegetation cover, which is often critical habitat for threatened animals. We examined the direct and indirect impacts of horses, kangaroos, and rabbits on the broad-toothed rat (Mastacomys fuscus), a threatened rodent in subalpine grasslands in Kosciusko National Park, which contains a large wild horse population. Our objective was to examine the relationship between the activity of different herbivores and 1) structural attributes of the vegetation (cover and density of different plant groups) and 2) length of broad-toothed rat runways and the presence of scat along these runways as proxies of broad-toothed rat activity. We assessed herbivore activity and measured vegetation cover, structure, and richness and total length of runways used by broad-toothed rats as a measure of activity. We used structural equation modeling to test the hypothesis that horse activity would lead to reductions in rat habitat directly, by increasing disturbance, and indirectly, by altering vegetation structure. Quadrats showing no evidence of horse activity had longer broad-toothed rat runways, taller but fewer grasses, double the shrub cover, and lower plant richness than quadrats showing evidence of horse activity. Structural equation modeling showed that there were no significant direct associations between horse activity and rat activity. However, increasing horse activity was associated with an indirect negative effect on broad-toothed rat activity by suppressing the positive relationship between grass height and rat activity. There were no significant effects of rabbits on any environmental variables, and kangaroo grazing was associated with an increase in shrub cover only. Disturbance by horses likely alters vegetation structure, by reducing grass height, making it less suitable for broad-toothed rats, thereby reducing their populations. Horses should be restricted from accessing critical broad-toothed rat habitat. © 2018 The Society for Range Management
  • Grass Yields Under Clipping and Watering Explain Varied Efficacy of Management Intensive Grazing on Rangelands

    Broadbent, T.S.; Bork, E.W.; Cooke, J.E.; Willms, W.D. (Elsevier Inc., 2019-05)
    Management intensive grazing (MIG) may not maximize plant productivity on rangelands because of morphophysiological traits of grassland vegetation. We examined defoliation and moisture effects on the biomass yield of rhizomatous and caespitose grass pairs that were either phylogenetically similar or of similar agroclimatic adaptation, including two agronomic grasses. From relatively low to high moisture regime adaptation, species pairs included western wheatgrass (Pascopyrum smithii [Rydb.] A. Love) and needle-and-thread (Hesperostipa comata [Trin. & Rupr.] Barkw.), northern wheatgrass (Elymus lanceolatus [Scribn. & J.G. Sm.]) and western porcupine grass (H. curtiseta [Hitchc.] Barkw.), plains and foothills rough fescue (Festuca hallii [Vasey] and F. campestris Rydb.), and smooth and meadow brome (Bromus inermis Leyss. and B. riparius Rehm). Response variables were shoot yield, root-shoot ratio, and water-use efficiency. We hypothesized that caespitose grasses, regardless of their origin or adaptation to agroclimate regime, would respond more determinately in biomass accumulation. Defoliation effects on shoot biomass were more pronounced under high moisture. Low intensity − high frequency defoliation yielded similarly to deferred controls in all grasses, and the same was true for high-intensity − low-frequency (HILF) defoliation in 1 rhizomatous grass. Three of the 4 rhizomatous grasses and 1 caespitose grass yielded greater under HILF defoliation compared with high-intensity − high-frequency defoliation. Caespitose grasses allocated more biomass to roots under low moisture conditions. Water-use efficiency decreased under high moisture conditions and more intense and/or frequent defoliation and peaked in agronomic grasses. Overall, our results suggested that growth patterns corresponded more with phylogenetic similarity as opposed to growth form. A conceptual model from these results showed that across all species, only the introduced bromes generated greater biomass under HILF defoliation, and this may explain why past research consistently concludes that MIG does not enhance plant productivity on rangelands. © 2018 The Society for Range Management
  • Fire Return Interval and Season of Fire Alter Bud Banks

    Russell, M.L.; Vermeire, L.T.; Ganguli, A.C.; Hendrickson, J.R. (Elsevier Inc., 2019-05)
    Despite the importance of vegetative reproduction in annual tiller replacement, little is known about the patterns and timing of tiller recruitment from the bud bank, especially regarding fire return intervals and seasons of fire. We examined aboveground plant density, temporal patterns of tiller production, and belowground bud bank dynamics for Bouteloua gracilis (Willd ex. Kunth) Lag. ex Griffiths), Pascopyrum smithii (Rydb.) A. Löve, and Hesperostipa comata (Trin. & Rupr.) Barkworth following summer, fall, and spring prescribed fires at 2-yr, 3-yr, and 6-yr fire return intervals, and their interactions. Fire treatments were initiated in 2006, and buds were assessed July 2011 through July 2013. Density and number of reproductive B. gracilis tillers increased in 2013 following drought during 2012, unlike H. comata, which decreased reproductive tiller production. Irrespective of fire treatments, B. gracilis produced the most buds (8 − 10 buds ∙ tiller− 1) and H. comata produced the least (2 − 3 buds ∙ tiller− 1), with P. smithii producing an intermediate amount (6 − 8 buds ∙ tiller− 1). Immediate B. gracilis and P. smithii bud mortality did not occur for all season and fire return interval treatments. However, H. comata bud mortality increased immediately following summer and fall prescribed fires. Three-yr fire return intervals increased active buds throughout the 2013 winter and growing season for B. gracilis and P. smithii relative to control plots and 2- and 6-yr fire return intervals. Fire stimulated bud activity of B. gracilis and P. smithii relative to nonburned plots. The aboveground and belowground response of H. comata indicated meristem limitations following fire treatments, illustrating greater vulnerability to fire for that species than B. gracilis and P. smithii. © 2018
  • Fire Risk in Revegetated Bunchgrass Communities Infested with Bromus tectorum

    Link, S.O.; Hill, R.W.; Bansal, S. (Elsevier Inc., 2019-05)
    In rangeland ecosystems, invasive annual grass replacement of native perennials is associated with higher fire risk. Large bunchgrasses are often seeded to reduce cover of annuals such as Bromus tectorum L. (cheatgrass), but there is limited information about how revegetation reduces fire risk over the long term. We assessed how revegetated community composition influences fire risk at three sites in Columbia National Wildlife Refuge in Grant County, Washington that were revegetated with large bunchgrasses 8 − 18 years before the study. At each site, five replicates of 10 plots (10 × 10 m) were established. Fire risk was determined as the probability that a plot would completely burn following ignition at a randomly located point in each plot (i.e., if 8 of 10 plots burned, then fire risk was 80%). Preignition, cover of bunchgrasses, cheatgrass, forbs, and surface characteristics were determined for each plot. Fire risk was < 100%. However, fire risk was still relatively high around 73% and did not differ significantly among sites despite differences in cheatgrass and bunchgrass cover, which may have been attributable to other characteristics, such as high total fuels cover (> 80% at all sites) and unvegetated gap cover (soil and soil cryptogams, < 17%). This information can provide guidance for future studies with larger ranges of cover characteristics to develop robust fire risk models, which ultimately will be used to aid rangeland managers who need to specify reduction of fire risk after reestablishing large bunchgrasses in rangelands infested with cheatgrass. © 2018 The Society for Range Management

View more