• Use of Power Curves to Monitor Range Trend

      Tanke, W. C.; Bonham, C. D. (Society for Range Management, 1985-09-01)
      Type I and Type II errors and the power of the test when testing the null hypothesis of static range trend are discussed. The consequences associated with Type I and Type II errors are judged to be similar and therefore the probability of committing a Type I or Type II error should be equal. As an example, the current range trend monitoring program for the Moose Camp Allotment on USDA Forest Service land in southwestern Montana is capable of detecting a change in range condition of one condition class 83% of the time when the probability of Type I error is set at .17 (Prob[-Type I Error] = Prob [Type II Error] = .17). Doubling the sample size would increase the ability to detect a condition class change to 95% when the probability of Type I error is set at .05 (Prob[Type I Error] = Prob[Type II Error] = .05).
    • Video Imagery: A New Remote Sensing Tool for Range Management

      Everitt, J. H.; Nixon, P. R. (Society for Range Management, 1985-09-01)
      A multi-video system that provides immediately useful narrowband black-and-white imagery within the visible to near-infrared light (0.40- to 1.10-micrometer waveband) region of the electromagnetic spectrum was evaluated as a remote sensing tool to assess several ecological rangeland ground conditions in southern Texas. The system provided imagery to detect many variables including: the presence of weeds, heavy grazing, fertilized grassland, burned areas, and gopher and ant mounds. Certain narrowband filters provided better discrimination among vegetation than others. For example, a red narrowband filter provided the best imagery to distinguish between fertilized and nonfertilized bermudagrass [Cynodon dactylon (L.) Pers.]. These results demonstrated that narrowband multi-video imagery could assist in assessing some ecological ground conditions of rangelands.
    • Viewpoint: Forage and Range Research Needs in the Central Great Plains

      Vogel, K. P.; Gorz, H. J.; Haskins, F. A. (Society for Range Management, 1985-09-01)
      In the central Great Plains, pastures and rangelands often are not economically competitive with grain crops. This has led to increases in acreages of row crops at the expense of rangelands, pastures, and hay crops on marginal lands resulting in severe erosion problems. The productivity of forages, pastures, and rangelands needs to be increased to levels that would make them economically competitive with grain crops. Innovative research will be needed to develop the required knowledge and technology upon which productivity increases can be based. Pastures and rangelands in this area are usually components of production systems which may also include the feeding of hay, silage, crop residues, and other feeds. Coordinated research teams need to be formed that can focus on all components of these production systems. Research needs and objectives of these research teams can be categorized by the land capability classes of the three major ecological regions in this area, the tall-grass, mid-grass, and short-grass prairie. In all of these regions, a classification system that is production-oriented rather than climax-oriented is needed for both pastures and rangelands if effective control of soil erosion and optimal income per land unit are to be achieved. Interstate cooperation in establishing a research team for major ecological region would facilitate the most efficient use of research resources.