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A %*a-Bouteloua community, cultivated in the autumn of 1928 and abandoned in the spring of 1932, reverted to a community dominated by needle-and-thread (Stipa comata Trin. and Rupr.). An exclosure to prevent grazing was constructed in 1978 to include equal portions of previously cultivated and adjacent native range, while the remainder of the area continued to be subjected to moderate to heavy grazing pressure. This permitted a study to determine the effects of the brief period of cultivation on forage production, species recovery, and soil physical and chemical characteristics compared to those of native prairie. After 14 years of protection from grazing, needle-and-thread accounted for 79% of folk cover of the abandoned cultivation and 18% of the untreated range while blue grama [Boutelouagracilis(HBK.) Lag. ex Steud] occupied 1 and 51% on the same treatments, respectively. After 60 years, the soil on the abandoned cultivated area showed reduced carbon, total nitrogen, available phosphorus, and hydraulic conductivity but increased NOj-N. Grazing reduced hydraulic conductivity, NH,-N, available mineralizable nitrogen (chemical index), available phosphorus, and total carbohydrates but increased carbon, total nitrogen, and NOs-N. Cultivation and grazing resulted in reduced root mass. To facilitate a rapid transition from blue grama to needle-and-thread stable communities, input of energy, such as cultivation, may well be required.

. Our paper provides an ecological perspective on the interrelationship between livestock grazing and riparian areas through a review of topical literature. We also describe the Alberta Riparian Habitat Management Project (also known as "Cows and Fish"), and draw upon our experience to provide a perspective on future riparian management actions. Those actions should begin with an understanding that prairie landscapes evolved with herbivores, in a grazing regime timed and controlled by season and climatic fluctuations where grazing by native grazers was followed by variable rest periods. Prevailing range management principles represent an attempt to imitate the natural system and describe ecologically based grazing systems. Traditionally, range management guidelines have focused on grazing practices and impacts in upland, terrestrial rangelands, with a lack of attention devoted to riparian areas.Three decades of riparian investigation have quantified the effect unmanaged livestock grazing can have on range productivity and watershed function. We contend that suitable grazing strategies for riparian areas will be developed first by understanding the function of riparian systems and then by applying range management principles to develop riparian grazing strategies. A key step towards determining the fit of livestock grazing is an understanding of the formation of riparian systems and their ecological function. We describe riparian structure, function and process to provide linkages between livestock grazing, riparian vegetation health and stream channel dynamics. We summarize the effects of unmanaged livestock grazing on riparian habitats and fish and wildlife populations. The general conclusion is that unmanaged grazing results in overuse and degradation of riparian areas. The literature provides several options for the development of riparian grazing strategies. We provide an overview of strategies suitable for riparian areas in Southern Alberta which should maintain ecological function and sustained use. Nous examinons dans une perspective écologique les interrelations entre la paissance par les animaux de ferme et les zones de rivage telles qu'elles se dégagent d'une analyse bibliographique. En outre nous décrivons le Projet de gestion des habitats riverains de l'Alberta (également connu sous le vocable « Des poissons et des vaches » et nous puisons à même notre expérience pour offrir un éclairage sur les futures mesures de gestion des rivages. Ces mesures devraient s'appuyer sur le postulat que les paysages pastoraux ont évolué avec les herbivores selon un régime de paissance réglé par les saisons et par les fluctuations climatiques et dans lequel les phases de pâture par les herbivores naturels étaient suivies de phases de repos plus ou moins longues. Les principes acceptés de gestion des parcours naturels constituent une tentative d'imitation du système naturel. Nous décrivons plusieurs systèmes de pâturage écologique. Depuis toujours, les théoriciens de la gestion des parcours se sont intéressés surtout au...

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Question 1 Integrity and Ecological Status 85 7.2 Question 2-Plant Community Structure 86 7.3 Question 3-Does the site retain moisture (litter standards) 87 7.4 Question 4-Site/Soil Stability 88 7.5 Question 5-Noxious weed infestation ...90 8.0 Literature cited 92 Appendix 9. 1 Range Site Types in the Grassland Natural Region ..98 sedge 12 Dominant grass is a mid-grass species such as western porcupine grass, northern or western wheatgrass or needle-and-thread grass 17 12. Dominant grass species is blue grama grass 13 2. 3. 4.