• Toxic alkaloid concentration in tall larkspur species in the western U.S

      Ralphs, M. H.; Manners, G. D.; Pfister, J. A.; Gardner, D. R.; James, L. F. (Society for Range Management, 1997-09-01)
      Larkspur (Delphinium spp.) kills more cattle on mountain rangelands in the western U.S. than any other plant, disease or predator. The concentration of toxic alkaloids was measured in 4 larkspur species, at 10 locations, at 2-week intervals during the growing season. In addition, multi-year samples from previous studies were analyzed to determine year-to-year variation in toxic alkaloids. Mountain larkspur (D. glaucum Wats.) had the highest concentration of toxic alkaloids averaged over growth stages (1.01% of dry weight), tall, (D. barbeyi (L.) Huth) and waxy larkspur (D. glaucesens Rydb) were intermediate (0.65 and 0.49% respectively), and duncecap (D. occidentale S. Watts) was lowest (0.29%). Toxic alkaloid concentration generally declined as the plants matured. However, toxic alkaloids in tall larkspur at Yampa, Colo. increased slightly in the pod stage, and toxic alkaloids in waxy larkspur increased from the vegetative to the bud stage. Concentration of toxic alkaloids in tall and duncecap larkspur leaves were higher in plants growing in open sunlight than those shaded under aspen or conifer canopy. Toxic alkaloid concentration varied among individual plants (C.V. 20-60%). Knowledge of the toxic alkaloid concentration of larkspur populations can be used to predict the risk of larkspur poisoning.
    • Viewpoint: Implications of participatory democracy for public land planning

      Moote, M. A.; McClaran, M. P. (Society for Range Management, 1997-09-01)
      Non-traditional, collaborative public park approaches such as coordinated resource management have been proposed to improve the public participation process used in public land planning on rangelands. Either implicitly or explicitly, most advocates of such non-traditional approaches to public participation seem to embrace a participatory democracy model of governance. Whether or not this model for decision-making can practicably be implemented, given our current institution and leaal frameworks for public lands management, has not been closely examined. Criticisms of the traditional public participation process are catagorize into 5 main issues: efficacy; representation and access; information exchange and learning; continuity of participation; and decision-making authority. We use these categories to evaluate the feasibility of implementing participatory democracy-based decision-making in public lands planning. Although there is some statutory and regulatory authority for participatory democracy in public land planning, there are a number of logistical, legal, and even philosophical challenges to its application that warrant further consideration.
    • Viewpoint: On rangeland carrying capacity

      Roe, E. M. (Society for Range Management, 1997-09-01)
      A new typology shows that the notion of rangeland carrying capacity has considerable ambiguity even under conditions of high environmental certainty. When these environmental conditions are highly uncertain, rangeland carrying capacity must be reconceived as a Hahn equilibrium in order to be useful for rangeland development and management. A Hahn equilibrium is a state of affairs which does not cause decision-making agents to change the (meta-)-theories which they hold or the (meta-)-policies which they pursue in their decision-making.
    • Viewpoint: The black-tailed prairie dog—headed for extinction?

      Wuerthner, G. (Society for Range Management, 1997-09-01)
      The black-tailed prairie dog (Cynomys ludovicianus) is 1 of 5 western prairie dog species, and the only species found on the Great Plains. Some authorities believe the black-tailed prairie dog may have been the most numerous of mammalian herbivores found on the plains with some estimates placing their historic numbers as high as 5 billion. Due to a combination of factors including habitat destruction, hunting, plague, and poisoning programs, the black-tailed prairie dog may now be threatened with extinction across its entire range. In this paper, a tentative prairie dog conservation strategy consisting of core reserves, buffer areas, and corridors is proposed.