• Using Leaf Fluorescence for Evaluating Atrazine Tolerance of Three Perennial Warm-Season Grasses

      Bahler, C. C.; Moser, L. E.; Vogel, K. P. (Society for Range Management, 1987-03-01)
      Atrazine [6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine] blocks photosynthetic electron transport in susceptible plants. The energy from the interrupted electron transport is fluoresced from the leaves of atrazine-treated plants. The purpose of this study was to evaluate leaf fluorescence as a nondestructive bioassay of the relative atrazine tolerance of 3 perennial, warm-season grasses. Leaf section of switchgrass [Panicum virgatum L.] (high tolerance), indiangrass [Sorghastrum nutans (L.) Nash] (intermediate tolerance), and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] (lower tolerance) were placed in distilled water for 20 min and then in atrazine solutions. Fluorescence readings were taken prior to and after the atrazine treatment with a portable fluorometer. The difference between the 2 readings provided a reliable measure with low variability of the relative atrazine tolerance of the grasses studied and was effective on greenhouse-and field-grown plants. Optimum atrazine concentrations and incubation periods were 10^-3 M (atrazine in distilled H2O and 30 min, respectively.
    • Using Leaf Traits to Rank Native Grasses According to Their Nutritive Value

      Khaled, Raounda Al Haj; Duru, Michel; Decruyenaere, Virginie; Jouany, Claire; Cruz, Pablo (Society for Range Management, 2006-11-01)
      Leaf traits (leaf dry matter content [LDMC], specific leaf area [SLA] and leaf life span [LLS]) previously proposed to predict plant strategies for resource use, were studied to test if they can be used to rank grasses for digestible organic matter (DOM). On 14 native grass species from natural meadows in the French Pyrenees, leaf blade chemical components (fiber, cellulose, hemi-cellulose and lignin) and DOM were estimated for two growing periods using two different methods (chemical-enzymatic and Near Infrared Reflectance Spectroscopy). The ranking of species based on LDMC, SLA and LLS was conserved. Fiber content and DOM were significantly correlated even though the data were obtained in different years (2001 and 2002), on different organs (youngest adult blades in 2001 and all the green blades of tillers in 2002) and by different analytical methods. LDMC seems to be the most suitable trait to rank native grasses according to their nutritive value because it ranks species as well as leaf traits and it is the easiest to measure. We suggest using LDMC as an indicator to rank grassland communities for herbage nutritive values.
    • Using Light Attenuation to Estimate Leafy Spurge Impacts on Forage Production

      Rinella, Matthew J.; Sheley, Roger L. (Society for Range Management, 2006-07-01)
      Rangeland managers often must decide whether to suppress dicotyledonous weed populations with expensive and time-consuming management strategies. Often, the underlying goal of weed suppression efforts is to increase production of native forage plants. Many managers suppress weeds only when they feel the unwanted plants are substantially impacting their forage base. Currently, intuition and guesswork are used to determine whether weed impacts are severe enough to warrant action. We believe scientific impact assessments could be more effective than these casual approaches to decision making. Scientific approaches will necessitate data on weed abundances because the severity of a weed’s impact is highly correlated with its abundance. The need for weed abundance data poses major obstacles because gathering these data with readily available techniques is time consuming. Most managers cannot or will not spend a lot of time gathering vegetation data. In this paper, we explore a rapidly measured index (<2 minutes per sample location) that is highly correlated with weed (i.e., leafy spurge Euphorbia esula L.) abundance per unit area. This index is based on the light attenuation leafy spurge causes. After measuring light attenuation in plots planted to leafy spurge and grasses, we developed a probabilistic model that predicts leafy spurge impacts on forage production. Data from experiments where herbicides suppressed leafy spurge provided an opportunity to evaluate prediction accuracy of the model. In each case herbicide experiment data fell within the range of values (i.e., credibility intervals) the model predicted, even though the model development experiments were separated from the herbicide experiments by several hundred kilometers in space and 4 years in time. Therefore, we conclude that the model successfully accounts for spatial and temporal variation. We believe light attenuation could help natural resource managers quickly quantify some kinds of weed impacts.  
    • Using multivariate techniques to quantitatively estimate ecological stages in a mixed grass prairie

      Uresk, D. W. (Society for Range Management, 1990-07-01)
      Cluster analysis followed by stepwise discriminant analysis was used to delineate ecological stages on a mixed grass prairie in western South Dakota. Forty-seven variables were analyzed for 48 sites ranging from potential vegetatlon to early seral stages. A cover-frequency index for western wheatgrass (Agropyron smithii), blue grama (Bouteloua gracilis), and buffalograss (Buchloe dactyloides) was the most valuable in identifying 4 different (P<0.0001) ecological stages. Ecological stage classification was estimated to be 95% accurate. The methods presented are quantitative, precise, easy, time-efficient, and meet the goals of resource managers with a minimum of bias.
    • Using Participatory Workshops to Integrate State-and-Transition Models Created With Local Knowledge and Ecological Data

      Knapp, Corrine Noel; Gimenez, Maria Fernandez; Kachergis, Emily; Rudeen, Aleta (Society for Range Management, 2011-03-01)
      State-and-transition models (STMs) depict current understanding of vegetation dynamics and are being created for most ecological sites in the United States. Model creation is challenging due to inadequate long-term data, and most STMs rely on expert knowledge. There has been little systematic documentation of how different types of knowledge have been integrated in STMs, or what these distinct knowledge sources offer. We report on a series of participatory workshops where stakeholders helped to integrate STMs developed for the same region using local knowledge and ecological field data. With this exploratory project, we seek to understand what kinds of information local knowledge and ecological field data can provide to STMs, assess workshops as a method of integrating knowledge and evaluate how different stakeholders perceive models created with different types of knowledge. Our analysis is based on meeting notes, comments on draft models, and workshop evaluation questionnaires. We conclude that local knowledge and ecological data can complement one another, providing different types of information at different spatial and temporal scales. Participants reported that the workshop increased their knowledge of STMs and vegetation dynamics, suggesting that engaging potential model users in developing STMs is an effective outreach and education approach. Agency representatives and ranchers expressed the value of both the local knowledge and data-driven models. Agency participants were likely to critique or add components based on monitoring data or prior research, and ranchers were more likely to add states and transitions based on personal experience. As STM development continues, it is critical that range professionals think systematically about what different forms of data might contribute to model development, how we can best integrate existing knowledge and data to create credible and useful models, and how to validate the resulting STMs.
    • Using Precipitation to Predict Range Herbage Production in Southwestern Idaho

      Hanson, C. L.; Morris, R. P.; Wight, J. R. (Society for Range Management, 1983-11-01)
      Analyses of 9 years of herbage yield and precipitation data from the Reynolds Creek Experimental Watershed in southwest Idaho show that annual herbage yield can be estimated by the Sneva and Hyder procedure (Sneva and Hyder 1962a, 1962b) at locations other than where their procedure was developed. These analyses did indicate that for sites below 1,680 m, their procedure was more useful when the crop-year precipitation index was based on a variable number of winter and spring months, rather than September through June. For sites above 1680 m, using winter and spring separately in a modified form of their basic equation may improve yield predictions.
    • Using Range Condition Assessment to Optimize Wildlife Stocking in Tindress Wildlife Sanctuary, Nakuru District, Kenya

      Muya, Shadrack M.; Kamweya, Able M.; Muigai, Anne W. T.; Kariuki, Apollo; Ngene, Shadrack M. (Society for Range Management, 2013-07-01)
      Over 70% of Kenya’s wildlife resources occur outside protected areas, in areas where land use practices do not necessarily conform to wildlife conservation standards. Ensuring that land use practices in these areas accommodate wildlife conservation is vital in effectively conserving wildlife in this country. Tindress Farm in Rift Valley offers a good example of a place where economic activities and wildlife conservation can work harmoniously. The farm has set up a 320-ha wildlife sanctuary in the hilly parts of the property to provide a haven for wildlife displaced by human settlements in the surrounding environs. The Tindress Farm management needed to know the diversity and optimum number of wildlife species that the sanctuary could accommodate. This study set out to 1) outline a set of models for objectively calculating wildlife stocking levels and 2) demonstrate the practical use of these models in estimating optimum stocking levels for a specific wildlife sanctuary. After comparing models using forage inventory methods models and utilization-based methods (UM), we opted to use UM models because of their focus on ecological energetics. This study established that the range condition in Tindress Wildlife Sanctuary varied from poor to good (29-69%) and recommended a total stocking density of 158.9 grazer units and 201.4 browser units shared out by the various herbivore species. These estimates remain a best-case scenario. The effects of rainfall, range condition, and condition of the animals should be monitored continuously to allow for adjustments through active adaptive management.
    • Using Rangelands on the Web as a Teaching Resource

      Tanaka, John; Hutchinson, Barbara; Fraker-Marble, Merrita; Frost, Rachel; Launchbaugh, Karen; George, Mel (Society for Range Management, 2012-06-01)
      Do your students go to Wikipedia for their reference material? Do they know where the library is and how to use it? Do they do general searches of the internet and spew forth whatever they find as facts? Do you wish there were better sources of information on rangelands to which you could direct them? We might just have a solution for you! 
    • Using Science to Bridge Management and Policy: Terracette Hydrologic Function and Water Quality Best Management Practices in Idaho

      Corrao, Mark V.; Cosens, Barbara E.; Heinse, Robert; Eitel, Jan U. H.; Link, Timothy E. (Society for Range Management, 2015-12-01)
      On The Ground • Nonpoint source (NPS) pollution is a leading cause of water quality degradation on 40% of the semiarid lands within the western United States, with sediment from runoff on agricultural lands making up 15%. • Managing NPS pollution through best management practices (BMPs) relies on site-specific knowledge and voluntary application. • The dominant hydrologic processes in semiarid environments are a product of local climate, vegetation, and soil conditions; therefore, land use and ecosystem resilience invariably hinge on a balance of shifting, and often competing, social and environmental drivers. • Our measurements of terracette hydrologic function and existence on more than 159,000 hectares within Idaho enabled an estimate of potential NPS erosion and sediment generation, emphasizing the value of site-specific scientific research for land managers. • Our study provides an example of how microtopographic landforms, such as terracettes, are connected with state and federal clean water policy as one example of how interdisciplinary research can have far-reaching application.
    • Using Sodium Carbonate to Seal Leaky Stock Ponds in Eastern Montana

      Neff, E. L. (Society for Range Management, 1980-07-01)
      Mixing sodium carbonate into the top 100 to 150 mm of soil in three farm ponds constructed in calcareous soil in eastern Montana effectively reduced seepage losses for about 3 years following treatment. Seepage rates the first year after treatment were decreased to 20 to 40% of the pretreatment rate, but they were 60 to 100% of the pretreatment rate 4 years after treatment.
    • Using Stubble Height to Monitor Riparian Vegetation

      Bryant, Larry; Burkhardt, Wayne; Burton, Tim; Clary, Warren; Henderson, Rick; Nelson, Dave; Ririe, Warren; Sanders, Ken; Wiley, Ron (Society for Range Management, 2006-02-01)
    • Using Terms: Management-intensive Grazing or Management Intensive Grazing

      Gerrish, Jim; Ohlenbusch, Paul D. (Society for Range Management, 1998-04-01)
    • Using the Forage Resource on the Eastern Slopes of the Canadian Rockies

      Bennett, R. H. (Society for Range Management, 1956-11-01)
    • Using the Green and Ampt infiltration equation on native and plowed rangeland soils

      Hutten, N. C.; Gifford, G. F. (Society for Range Management, 1988-03-01)
      Soil textural relationships were used on 3 soil series on both plowed and native rangeland to predict Green and Ampt infiltration equation parameters. Infiltration rates predicted from the Green and Ampt soil texture relationships were regressed against field infiltration rates. Good predictability was found on only 4 of 94 plots, all of which were in the agricultural area. Results indicate that current soil texture relationships developed for estimating infiltration rates may not be sufficient for use in either agricultural or rangeland semiarid environments. At this point in time, if infiltration values are important, then they should be measured (not estimated) using appropriate methodologies.
    • Using the GRI on the West Terror Allotment

      Bradford, David (Society for Range Management, 1999-08-01)
    • Using Unmanned Helicopters to Assess Vegetation Cover in Sagebrush Steppe Ecosystems

      Breckenridge, Robert P.; Dakins, Maxine; Bunting, Stephen; Harbour, Jerry L.; Lee, Randy D. (Society for Range Management, 2012-07-01)
      Evaluating vegetation cover is an important factor in understanding the sustainability of many ecosystems. Remote sensing methods with sufficient accuracy could dramatically alter how biotic resources are monitored on both public and private lands. Idaho National Laboratory (INL), in conjunction with the University of Idaho, evaluated whether unmanned aerial vehicles (UAVs) are sufficiently accurate and more efficient than the point-frame field method for monitoring vegetative cover and bare ground in sagebrush steppe ecosystems. These values are of interest to land managers because typically there are limited natural resource scientists and funding for comprehensive ground evaluations. In this project, unmanned helicopters were used to collect still-frame imagery to determine vegetation cover during June and July 2005. The images were used to estimate percent cover for six vegetative cover classes (shrub, dead shrub, grass, forbs, litter, and bare ground). Field plots used to collect imagery and on-the-ground measurements were located on the INL site west of Idaho Falls, Idaho. Ocular assessments of digital imagery were performed using SamplePoint, and the results were compared with field measurements collected using a point-frame method. The helicopter imagery evaluation showed a high degree of agreement with field cover class values for grass, litter, and bare ground and reasonable agreement for dead shrubs. Shrub cover was often overestimated, and forbs were generally underestimated. The helicopter method took 45% less time than the field method. This study demonstrates that UAV technology provides a viable method for monitoring selective types of cover on rangelands and could save time and resources./Evaluar la cobertura vegetal es un importante factor para entender la sustentabilidad de muchos ecosistemas. Métodos de teledetección con suficiente precisión pueden considerablemente alterar la manera en como los recursos bióticos son monitoreados tanto en propiedad privada y pública. El laboratorio Nacional de Idaho (INL), en conjunto con la universidad de Idaho, evaluaron si vehículos aéreos no tripulados (UAVs) son suficientemente precisos y más eficientes que los métodos de campo basados en punto de referencia para monitorear la cobertura de las vegetación y el suelo desnudo en los ecosistemas de pastizales de Artemisia. Estas evaluaciones son de interés para los manejadores de tierra ya que normalmente hay poco scientíficos dedicados al estudio de los recursos naturales así como escasos recursos monetarios para evaluaciones integrales. En este proyecto, helicópteros no tripulados fueron usados para recolectar imágenes usadas para determinar la cobertura vegetal durante junio y julio de 2005. Las imágenes fueron usadas para estimar el porcentaje de cobertura de seis clases de cubierta vegetal (arbustos, arbustos muertos, pastos, herbáceas, hojarasca y suelo desnudo). Parcelas de campo que fueron usadas para recolectar las imágenes así como las mediciones en campo fueron localizadas en el sitio INL al oeste de Idaho Falls, Idaho. Evaluaciones oculares de imágenes digitales fueron realizadas usando SamplePoint y los resultados fueron comparados con las mediciones de campo recolectadas usando el método de point-frame. La evaluación de las imágenes recolectadas por el helicóptero mostró un alto grado de correlación con respecto a las evaluaciones de campo para pastos, hojarasca, y suelo desnudo, y una razonable relación para plantas muertas. Las cobertura de los arbustos fue regularmente sobrestimado y para las herbáceas fueron generalmente subestimadas. El método del helicóptero tomo 45% menos tiempo que el método de campo. Este estudio demostró que la tecnología UAV proporciono un método viable para monitorear los tipos selectivos de cobertura en los pastizales y podría salvar tiempo y recursos.
    • Using Very-Large-Scale Aerial Imagery for Rangeland Monitoring and Assessment: Some Statistical Considerations

      Karl, Jason W.; Duniway, Michael C.; Nusser, Sarah M.; Opsomer, Jean D.; Unnasch, Robert S. (Society for Range Management, 2012-07-01)
      The availability of very-large-scale aerial (VLSA) imagery (typically less than 1 cm ground-sampling-distance spatial resolution) and techniques for processing those data into ecosystem indicators has opened the door for routinely using VLSA imagery in rangeland monitoring and assessment. However, for VLSA imagery to provide defensible information for managers, it is crucial to understand the statistical implications of designing and implementing VLSA image studies, including consideration of image scale, sample design limitations, and the need for validation of estimates. A significant advantage of VLSA imaging is that the researcher can specify the scale (i.e., spatial resolution and extent) of the images. VLSA image programs should plan for scales that match monitoring questions, size of landscape elements to be measured, and spatial heterogeneity of the environment. Failure to plan for scale may result in images that are not optimal for answering management questions. Probability-based sampling guards against bias and ensures that inferences can be made to the desired study area. Often collected along flight transects, VLSA imagery lends itself well to certain probability-based sample designs, such as systematic sampling, not often used in field studies. With VLSA image programs, the sample unit can be an entire image or a portion of an image. It is critical to define the sampling unit and understand the relationship between measurements and estimates made from the imagery. Finally, it is important to statistically validate estimates produced from VLSA images at selected locations using quantitative data of the same scale and more precise and accurate than the VLSA image techniques. The extent to which VLSA imagery will be useful as a tool for understanding the status and trend of rangelands depends as much on the ability to build the imagery into robust programs as it does on the ability to quickly and relatively easily collect VLSA images over large landscapes./La disponibilidad de imágenes aéreas a gran escala (IAGE) (normalmente menos de un cm de de distancia de resolución espacialen el terreno) y técnicas que procesen esos datos dentro de indicadores del ecosistema han abierto la puerta para que de manera rutinaria se use IAGE en pastizales en monitoreo y evaluación. Sin embargo, para IAGE proveer información defendible para administradores es crucial para entender las implicaciones estadísticas para diseñar e implementar estudios de IAGE que incluyan consideraciones de escala de la imagen, limitaciones en el diseño de muestreo y la necesidad de validación de los estimadores. Una ventaja significativa de IAGE es que el investigador puede definir la escala (ejm. resolución espacial y extensión) de la imagen. Los programas de IAGE deberían planear escalas que empaten preguntas de monitoreo, el tamaño delos elementos del paisaje a ser medidos y la heterogeneidad espacial del medioambiente. Fallas en planear la escala puede resultar en imágenes que no son optimas en resolver las preguntas del administrador. Muestreos basados en probabilidad protegen contra sesgo y aseguran que la inferencia puede ser hecha para la area de estudio deseada. Seguido, recolección a lo largo de vuelos en transectos, IAGE permite bien a cierto diseño de muestra basado en probabilidad como diseño sistemático nousado a menudo en estudios de campo. Con programas IAGE la unidad de muestreo puede ser la imagen completa o una porción de ésta. Es fundamental definir la unidad de muestreo y entender la relación entre medidas y estimaciones hechas de la imagen. Finalmente, es importante validar estadísticamente los estimadores producidos de IAGE es lugares seleccionados usando datos cuantitativos de la misma escala y más precisos y certeros que las técnicas de IAGE. La amplitud a la cual IAGE será de utilidad como herramienta para entender el estatus y tendencia de los pastizales, depende en gran medida en la habilidad para construir imágenes en programas robustos sino también con la habilidad de recolectar imágenes IAGE rápidamente y relativamente fácil sobre grandes paisajes.
    • Using Weather Data to Explain Herbage Yield on Three Great Plains Plant Communities

      Smart, Alexander J.; Dunn, Barry H; Johnson, Patricia S.; Xu, Lan; Gates, Roger N. (Society for Range Management, 2007-03-01)
      Understanding the drivers that account for plant production allows for a better understanding of plant communities and the transitions within ecological sites and can assist managers in making informed decisions about stocking rates and timing of grazing. We compared climatic drivers of herbage production for 3 plant communities of the Clayey ecological site in southwestern South Dakota: the midgrass community dominated by western wheatgrass (Pascopyrum smithii [Rybd.] A. Love); the mixed-grass community codominated by western wheatgrass, blue grama (Bouteloua gracilis [H.B.K.] Lag. Ex Griffiths), and buffalograss (Buchloe dactyloides [Nutt.] Engelm.); and the shortgrass community dominated by blue grama and buffalograss. We used herbage yield and weather data for the period 1945-1960 collected at the South Dakota State University Range and Livestock Research Station near Cottonwood, South Dakota, to develop stepwise regression models for each plant community. Midgrass herbage production was best predicted by current-year spring (April-June) precipitation, number of calendar days until the last spring day with minimum temperature 18C, and previous-year spring precipitation (R2 = 0.81). Mixed-grass herbage production was best predicted by current-year spring precipitation and days until the last spring freeze (R2 = 0.69). Shortgrass herbage production was best predicted by current-year spring precipitation (R2 = 0.52). Midgrass plant communities were, overall, 650 kg ha-1 (SE = 92 kg ha-1) more productive (P < 0.01) than mixed- or shortgrass plant communities given the same climatic inputs. Our study enables managers to make timely informed decisions regarding stocking rates and timing of grazing on this ecological site in western South Dakota. 
    • Using Weather Records with a Forge Production Model to Forecast Range Forage Production

      Wight, J. R.; Hanson, C. L.; Whitmer, D. (Society for Range Management, 1984-01-01)
      This paper describes a method for calculating site specific forecast yields and their associated probabilities of occurrence. A physically based range forage model, which utilizes beginning soil water content and daily precipitation, mean air temperature, and solar radiation as inputs, calculates the ratio of actual transpiration (T) to potential transpiration (Tp) as a yield index. Annual yield is calculated by the relationship: yield = potential site yield (yield when water is nonlimiting) × T/Tp. By using the current year's beginning soil water content and weather data for a number of years, a population of yields is generated (one yield for each year of weather data). From the population of yields, a mean and various confidence intervals around the mean can be calculated as the forcast yield and its associated confidence intervals. The forecast procedure was tested using 55 years (1917-1971) of weather records and 12 years (1967-1978) of actual yield and soil water data for an upland range site in eastern Montana. An expected two thirds of the field measured yields were within a standard deviation of the forecasted yields for the April, May, and June forecasts.
    • Using WebGIS to Develop a Spatial Bibliography for Organizing, Mapping, and Disseminating Research Information: A Case Study of Quaking Aspen

      Howell, R.G.; Petersen, S.L.; Balzotti, C.S.; Rogers, P.C.; Jackson, M.W.; Hedrich, A.E. (Society for Range Management, 2019-12)
      Spatial data is valuable to researchers for locating studies that occur in a particular area of interest, or one with similar attributes. Without a standard in publishing protocol, spatial data largely goes unreported, or is difficult to find without searching the publication. Assigning location data and displaying points on a public web map makes locating publications based on spatial location possible.