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GRAZING EFFECTS ON WOODY PLANT ESTABLISHMENT <br />The use of grazing as a management tool to increase woody <br />species establishment has historically been a principle range <br />science assumption. A review of the literature has revealed that <br />very few, if any, studies have addressed the direct impact of <br />grazing on woody species establishment, but rather discuss the <br />direct effects of grazing on the herbaceous component and its <br />indirect effect on shr~ib establishment. <br />Several studies provide evidence which supports the assumption <br />that upon removal of certain herbaceous species, the density of <br />shrubs increases or remains the same (Steward 1940; Buffington and <br />Herbel 1965; Watts et al. 198T). Bailey et al. (1990} studied the <br />• effect of grazing on reducing aspen resprouts in Canada. They <br />reported that palatable shrubs decreased while unpalatable shrubs <br />(snowberry) increased under late season grazing. Coppack et al. <br />(1983) observes vegetational changes due to prairie dog <br />disturbances which favored a shift towards shrub dominated <br />communities. These examples provide some evidence supporting the <br />indirect effects of grazing on shrub production. <br />Historic observations provide evidence that lands which were <br />predominantly grass dominated prior to heavy grazing are now <br />dominated by shrub species (Heady 1988). These types of <br />observations are also addressed by ycGinr_ies et al. (1941} in the <br />southwest when they stated that "It is very apparent that there has <br />been an increase in the rate of invasion of woody species since the <br />• coming of white man to the western range country." This statement <br />correlates with the increased grazing pressure accompanied by white <br />