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Sod-seeding techniques offer graziers a convenient way to introduce superior grass cultivars into underproductive permanent pastures. Production loss and erosion are minimized. In conjunction with improved grazing management and fertilization, renovation can significantly improve yield and quality of pastures. Existent vegetation must be suppressed prior to introducing new cultivars. This study was conducted on two non-irrigated pastures near Corvallis, Oregon, one dominated by annual grass species and the other by perennial grasses and clover. A split-plot design with four replications on each site was used to compare three seeding methods and either (a) two herbicides following close mowing or (b) close mowing alone. The seeding methods were drilling with an Aerway Seedmatic chisel-type drill, drilling with a Tye double disc drill, or broadcasting seed followed by harrowing. Glyphosate and paraquat were the herbicides used for vegetation suppression. Effect of fertilization was compared to no fertilization. Sod-seeded perennial ryegrass had minimal establishment at the site dominated by annual grass species. An inadequate amount of time was allowed for germination of annual grass seeds before herbicides were applied. Annual grass seedlings suppressed the newly sod-seeded perennial ryegrass. Sod-seeded perennial ryegrass was successfully established at the site dominated by perennial species within one year after planting. Broadcasting followed by harrowing of seed resulted in a higher percentage of perennial ryegrass than either the Seedmatic chisel drill or Tye double disc drill. Sod-seeded perennial ryegrass did not contribute significantly to yield until one year after planting. Glyphosate gave better control of the species present before planting leading to a higher percentage of perennial ryegrass and improved yield compared to paraquat or close mowing alone when seed was broadcast and harrowed. Fertilization of unseeded plots increased yield but was not cost-effective. / Graduation date: 1994

Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on June 26, 2009). Includes bibliographical references (p. 34-35).

8 pp. / Originally published: 1998 / Animal learning has been shown to play a major role in the development of diet selection by domestic herbivores. Dr. Frederick Provenza and his associates at Utah State University have conducted a series of studies over the past 30 years to learn how physiological and behavioral mechanisms govern diet selection. In this paper, we synthesize several key diet selection concepts presented in 4 articles (i.e., Provenza et al. 1992; Provenza 1995, 1996, 1997). Reviewed 12/2014; originally published 05/1998.

The objectives of this dissertation were to identify soil and vegetation changes due to grazing by livestock and to develop guidelines for monitoring the impact of livestock in the Sahelian zone of Africa. The study was conducted in eastern Senegal during 1983 to 1985. The basic methodology was a study of the process of degradation (retrogression) through the collection of data on soils and vegetation along a gradient of increasing livestock pressure. Two gradients were selected along piospheres. Each gradient was placed on a range site that had homogeneous state factors (climate, geology, and rainfall). The results show that the changes in the soil were confined to the top soil horizon. There was a negative correlation between livestock pressure and factors such as infiltration, percent nitrogen, and percent carbon, and a positive correlation between livestock pressure and the factors of bulk density, and phosphorous content. Changes in the vegetation community were dependent on the range site. On the sandy site, there was a linear, negative correlation between livestock pressure and the factors of plant density, plant cover and biomass. On the loamy range site, the changes in these factors along the gradient had a 2nd or 3rd order polynomial relationship. The effects of bush fires and short term droughts on the vegetation were also studied. Drought, in particular, has an impact that is similar to that of livestock pressure, and may compound the results. Multiple regression analysis and a Twinspan ordination program were used to select parameters and plant species that were highly correlated with the gradient, and could act as indicators of each stage of degradation. These indicators can be used to monitor the impact of livestock on rangelands. General parameters, such as total plant density, are less sensitive to drought-induced changes than the composition of indicator species, but the latter are easier to monitor. Both types of indicators can form the basis for a monitoring methodology that can be used in Africa at three management levels: the individual herder, extension agents and regional branches of the division concerned with rangelands, and policy makers at the ministerial level.

This dissertation develops a new organizational model based on sustainability criteria within which the organizational and technical solutions to the problems of management of extensive livestock production systems on the commons grazing lands can be provided. Due to the multifarious forces of modernization the traditional range/livestock systems developed by tribal peoples in arid and semiarid areas world-wide have largely been abandoned. The outcome has been extensive rangeland deterioration and expansion of desertification in many cases. The Apache Indian cattle association operations examined herein, the Mescalero single-brand and the San Carlos multiple-brand, are examples of livestock organizations operating extensive livestock production programs on commonly held rangelands. The results of these investigations provide the basis for developing this model.