• Experimental evaluation of the grazing optimization hypothesis

      Williamson, S. C.; Detling, J. K.; Dodd, J. L.; Dyer, M. I. (Society for Range Management, 1989-03-01)
      The herbivore grazing optimization hypothesis predicts an increase in aboveground net primary productivity (ANPP) at a moderate grazing intensity. The hypothesis was tested by grazing controlled densities (0 to 145 individuals/m2) of big-headed grasshoppers (Aulocara elliotti Thomas) for short time spans (7 to 13 days) on enclosed swards (0.7 m2) of blue grama [(Bouteloua gracilis) (Willd. ex H.B.K.) Lag. ex Griffiths]. ANPP of each of 257 experimental enclosures was estimated following regrowth by using a standing crop index (the product of mean total blade length per tiller and percent basal cover) after the grazing period and clipping after the regrowth period. ANPP was not significantly reduced by grazing in any of the 5 short-duration grazing experiments. In 2 of the 5 experiments, ANPP increased significantly with grazing. In 1 of the other 3 experiments there was evidence for the grazing optimization hypothesis.
    • Experimental evidence for sex-based palatability variation in fourwing saltbush

      Maywald, D.; McArthur, E. D.; Jorgensen, G. L.; Stevens, R.; Walker, S. C. (Society for Range Management, 1998-11-01)
      Two small-plot grazing trials were conducted in the spring of 1996 and the winter of 1997 to determine whether sheep would differentially graze fourwing saltbush [Atriplex canescens (Pursh) Nutt.] on the basis of shrub sex in a uniform garden. Consumption was determined using an Australian method of leaf tagging in conjunction with the Adelaide Technique of biomass estimation. The results confirmed anecdotal field observations that herbivores prefer to graze the male shrub during late spring. No sex based preference was apparent during winter. We suggest that differences in physiological vigor and/or chemistry may influence relative palatability of the sexes through time. Results of these experiments contrast with those for an Australian member of the genus (A. vesicaria Hew. ex Benth.), for which it was found that the female was the preferred phenotype throughout the year.
    • Experimental Stewardship Program—An Underpublicized Success Story

      Pence, Dan; Smith, Maynard; Frisina, Michael R. (Society for Range Management, 1993-08-01)
    • Experimental Stewardship—What’s Happening?

      Cleary, C. Rex (Society for Range Management, 1984-08-01)
    • Experimental Use of Remote Sensing by Private Range Managers and Its Influence on Management Decisions

      Betterfield, Scott H.; Malmstrom, Carolyn M. (Society for Range Management, 2006-09-01)
      Although remote sensing has many potential applications for range management, its use by range managers thus far has been limited. To investigate the factors that encourage use of remote sensing and to examine its influence on decision making by individuals who manage privately owned rangeland, we evaluated the decision-making processes of 3 ranch owners and 1 professional ranch manager who were introduced to remote sensing while collaborating with us in a rangeland stewardship program in California. Two of the participants had extensive ranching experience (11 to > 20 years) and managed large cattle ranches (1 000 to > 2 000 ha), and 2 had less experience and managed smaller sheep ranches (< 200 ha). During the 5-year program, the participants implemented a series of new management practices, including prescribed burning, rotational grazing, and seeding of native grasses, with the aim of reducing noxious weeds and increasing productivity. We used remote sensing to quantify the effect of these practices and provided ranch-wide remote sensing analyses to each manager on a password-protected Web site. Using case study methodologies, we found that managers of larger, commercially active ranches found the experimental use of remote sensing to be a highly positive experience that convinced them that this technology could help address difficult management situations and increase ranch profitability. This suggests that the broad use of remote sensing by managers of privately held, commercial rangelands may be limited in part by the simple lack of opportunity to test these technologies. Programs that assist ranchers in obtaining appropriate remote sensing products thus may be a cost-effective way to enhance conservation on private rangelands. Our findings suggest that voluntary self-analysis by ranchers of the landscape dynamics of their own properties is likely to lead to more engaged conservation efforts than will top- down prescriptions. 
    • Explaining Cattle Rancher Participation in Wildlife Conservation Technical Assistance Programs in the Southeastern United States

      Willcox, A. S.; Giuliano, W. M. (Society for Range Management, 2014-11)
      US natural resources and wildlife agencies have been increasing their efforts to involve cattle ranchers in wildlife conservation through technical assistance programs that provide for wildlife conservation activities. Understanding why ranchers choose to be involved in these programs is fundamental to increasing participation and ensuring their success. Using the theory of planned behavior as a theoretical model, we surveyed 1 093 ranchers in Alabama, Florida, Georgia, and Mississippi to explain and predict intention to participate in technical assistance programs, specifically, wildlife workshops and field days. All three theory components—attitude, subjective norm, and perceived behavioral control—were important to intent to participate and explained 41% of the variance, with perceived behavioral control and subjective norm having the greatest standardized effects (β = 0.329 and β = 0.316, respectively). Investigation of the construct components yielded insight into how agencies could increase participation. Ranchers generally held positive attitudes toward wildlife workshops, perceiving them to be a good way to learn about wildlife management and perceiving that most ranches were suitable for wildlife, an instance of perceived behavioral control. However, ranchers did not perceive that workshops and field days were widely advertised or promoted, limiting the amount of perceived control they had over their participation. Additionally, ranchers identified normative groups whose opinions were important to them, namely their families, friends and neighbors, fellow ranchers, and agency staff. However, these same groups were not seen to actively encourage ranchers to participate in technical field days and workshops. Using key members of these normative groups to advertise and promote workshops and field days among their peers should increase rancher behavioral control and attitudes associated with technical workshops and field days. Employing strategies from this research to increase attendance at technical workshops and field days should improve wildlife conservation technical assistance program effects. © 2014 Society for Range Management
    • Exploring Kentucky in 2008

      Johnson, Jennifer (Society for Range Management, 2007-10-01)
      From the rolling hills in the east to the beautiful lakes in the west, Kentucky has something for everyone. Kentucky is a state full of history and wonder, excitement and education. No matter what your interest, Kentucky can quench the thirst of any traveling enthusiast.
    • Exploring Southern Utah, 1872: The Diary of William Derby Johnson, Jr.

      Haver, Sherri (Society for Range Management, 1993-06-01)
    • Exploring the Eccentric

      Mills, Marianne (Society for Range Management, 1996-12-01)
    • Exporting Range Extension

      Kirmse, Robert D.; Dickie, Alex; Artz, Neal E.; Anderson, Val Jo (Society for Range Management, 1986-10-01)
    • Exposition on the Selection of Appropriate Experimental Design and Statistical Analysis for Pasture Improvement Research

      Stroup, W. W.; Waller, S. S.; Gates, R. N. (Society for Range Management, 1986-05-01)
      Selection of appropriate treatment and experiment designs are essential elements in research. However, the expense and variability associated with pasture renovation studies creates unique problems in the application of standard statistical techniques. Pasture-size renovation studies are restricted by expense, requiring the use of grazing exclosures (subsamples). Treatment design must include an adequate control for treatment comparison. Controls for pasture renovation practices cannot be limited to untreated areas within a grazing exclosure. The true measure response is found in the difference between treated areas and a typical grazed pasture situation. Criteria for exclosure selection (homogeneity) and heterogeneity of the grazed pasture may result in unequal variances or nonnormal error distributions, thus restricting the use of an analysis of variance. The experiment design must recognize the requirements for making reliable inferences. Pasture-to-pasture variability generally demands that pastures should be replicated in renovation studies to allow general inferences. Within pasture variability would support the need for multiple exclosures within each pasture. Costs associated with this kind of research limit the utility of idealized experimental designs. Several alternative experimental designs are discussed. Limitations in interpretation and risks of drawing erroneous or weak conclusions are reviewed.
    • Exposure May Influence Grassland Establishment

      Dillion, Claude C. (Society for Range Management, 1967-03-01)
      This example of the effect of exposure to grassland establishment can be useful to range management. South exposure sites in this climate will only recover to annual vegetation if perennial plants have been destroyed-that is, within a reasonable period of years. Reseeding would be an important consideration. Deferred grazing may not be beneficial on south exposure sites, but very desirable on north exposures where an excellent perennial grass stand could develop.
    • Expressing the Competitive Relationship between Wyoming Big Sagebrush and Crested Wheatgrass

      Rittenhouse, L. R.; Sneva, F. A. (Society for Range Management, 1976-07-01)
      Crested wheatgrass production was negatively correlated with Wyoming big sagebrush crown cover. Each 1% increase in sagebrush crown cover was associated with a decline in crested wheatgrass production equivalent to 3.3 to 5.2% of its potential within the range of cover measured. Expression of this relationship in the above manner may enable sounder economic analysis than conventional methods now used.
    • Extended grazing systems for improving economic returns from Nebraska sandhills cow/calf operations

      Adams, D. C.; Clark, R. T.; Coady, S. A.; Lamb, J. B.; Nielsen, M. K. (Society for Range Management, 1994-07-01)
      Three winter treatments were cross classified with 2 spring treatments to create 6 feeding and grazing systems utilizing Nebraska sandhills range and subirrigated meadow forage. Systems were evaluated with multiparous crossbred beef cows over 4 years (240 head beginning year 1). Systems were: 1) owing range during winter; 2) grazing subirrigated meadow during winter; and 3) fur feed of meadow bay during winter; in combination with either: a) full feed of subirrigated meadow hay during May, or b) grazing subirrigated meadow during May. From June through November all cows grazed range. The feeding and grazing systems were compared with selected linear contrasts and evaluated with respect to variable input prices. Some differences in cow body weight and body condition occurred but differences were considered small. Throughout the study, cows on all systems generally maintained a body condition score of about 5 (1 to 9 scale) year long. Inputs of hay were reduced by grazing range or subirrigated meadow during winter and during May without affecting pregnancy rate. Weaning weight of calves was increased 5.0 kg by grazing meadow during May compared to feeding hay during May. When opportunity costs were included in the analysis, the most profitable system involved grazing subirrigated meadow during winter and during May. Grazing subirrigated meadow during May enhanced the profitability of all wintering systems.
    • Extension Practices for Range Management at Abilene Christian College, Abilene, Texas

      Churchill, F. M. (Society for Range Management, 1951-09-01)
    • Extension Range Work in Texas

      Walker, A. H. (Society for Range Management, 1950-07-01)
    • Extent of Coterminous US Rangelands: Quantifying Implications of Differing Agency Perspectives

      Reeves, Matthew Clark; Mitchell, John E. (Society for Range Management, 2011-11-01)
      Rangeland extent is an important factor for evaluating critical indicators of rangeland sustainability. Rangeland areal extent was determined for the coterminous United States in a geospatial framework by evaluating spatially explicit data from the Landscape Fire and Resource Management Planning Tools (LANDFIRE) project describing historic and current vegetative composition, average height, and average cover through the viewpoints of the Natural Resources Inventory (NRI) administered by the Natural Resources Conservation Service and the Forest Inventory and Analysis (FIA) program administered by the US Forest Service. Three types of rangelands were differentiated using the NRI definition encompassing rangelands, afforested rangelands, and transitory rangelands. Limitations in the FIA definition permitted characterization of only two rangeland types: rangeland and rangeland vegetation with a small patch size. These classes were similar to those from the NRI definition but differed in tree canopy cover threshold requirements. Estimated rangeland area resulting from the NRI- and FIA-LANDFIRE models were 268 and 207 Mha, respectively. In addition, the NRI-LANDFIRE model identified 19 Mha of afforested rangelands due principally to encroachment and increased density by species classified as trees belonging to the genera Quercus, Prosopis, and Juniperus. The biggest discrepancies between acreage estimates derived from NRI- and FIA-LANDFIRE models occurred in oak, pinyon-juniper, and mesquite woodlands. The differences in area estimates between the NRI and FIA perspectives demonstrate the need for development of unified, objective methods for determining rangeland extent that can be applied consistently to all rangelands regardless of ownership or jurisdiction. While the models and geospatial information developed here are useful for national-scale estimates of rangeland extent, they are subject to the limitations of the LANDFIRE data products./La extensión de los pastizales es un importante factor para evaluar indicadores críticos de la sustentabilidad de estas aéreas. La extensión aérea de los pastizales se determinó por los colindantes de Estados Unidos (US) en un marco geoespacial para evaluar espacialmente los datos explícitos del proyecto LANDFIRE describiendo su composición botánica histórica y actual, altura promedio, y cobertura promedio mediante el uso los criterios desarrollados por el Natural Resources Inventory (NRI) administrado por el Natural Resources Conservation Service y el Forest Inventory and Analysis Program (FIA) administrado por el US Forest Service. Tres tipos de pastizales se evaluaron usando la definición del NRI abarcando: pastizales, pastizales forestados y pastizales transitorios. Limitaciones en la definición de la FIA solo permiten la caracterización de dos tipos de pastizales: pastizales y vegetación con pequeñas areas de pastizal. Estas clases fueron similares a aquellas de la definición de NRI pero difirieron en los requerimientos de la cubierta aérea de los árboles. Las areas de pastizal estimadas usando los modelos NRI y FIA-LANDFIRE fueron 268 y 207 Mha, respectivamente. Además, el modelo NRI-LANDFIRE identificó 19 Mha de pastizales forestados principalmente debido a la invasión y el incremento de la densidad de especies clasificadas como arboles pertenecientes al género Quercus, Prosopis, y Juniperus. Las mayores discrepancias entre la estimación de superficie generadas por los modelos NRI y FIA-LANDFIRE se identificaron en bosques de encino, piñón-junípero y mezquite. Las diferencias entre las estimaciones de perspectivas aéreas generadas entre los modelos NRI y FIA demostraron la necesidad de desarrollar un modelo unificado; los métodos objetivos para determinar la condición de los pastizales pueden aplicarse consistentemente a todos los pastizales sin importar propiedad y jurisdicción. Mientras que los modelos e información geoespacial desarrollados aquí son útiles para la estimación a escala nacional de la condición de los pastizales, aunque están sujetas a la limitación de los productos de datos generados por LANDFIRE.
    • Extent of Stem Dieback in Trembling Aspen (Populus tremuloides) as an Indicator of Time-Since Simulated Browsing

      Carson, Allan W.; Rea, Roy V.; Fredeen, Arthur L. (Society for Range Management, 2007-09-01)
      Simulated browsing treatments were imposed on an important browse species of the North American moose (Alces alces L.) to see if the development and extent of subsequent stem dieback in trembling aspen (Populus tremuloides Michx.) could be used to determine the time of browsing during the growing season. Two hundred naturally growing aspen saplings of similar size and form were randomly selected in a 20-ha area near the endowment lands of the University of Northern British Columbia, Prince George, British Columbia, Canada. Plants were randomly assigned to treatment categories so that the apical meristems of 50 plants each were assigned to a control or were clipped on one of the following dates 6 weeks apart: 1 June, 16 July, and 30 August 2005. The leader of each aspen was clipped and dieback was left to progress until the onset of winter dormancy. Our results showed that the earlier the simulated browsing occurs in the growing season, the greater the length of stem dieback, up to the maximum of the subapical axillary node below the point of clipping. The average rate at which dieback progressed varied between treatments and decreased throughout the growing season. Our results suggest that the ratio of the actual length of stem dieback to the overall length of stem between the clip point and the subapical axillary node serves as a good indicator for estimating the time at which aspen meristems have been browsed during the growing season. 
    • Extra 'Hands' for the Rancher

      Phillips, Pat (Society for Range Management, 1979-12-01)
    • Extracting Plant Root Samples with the Kelly Core Sampler

      Kinsinger, F. (Society for Range Management, 1955-09-01)