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After considering all the available evidence, Edwards notes that the Californian Pleistocene megafauna was a complex of grazing-browsing-trampling effects. Edwards infers that California's Pleistocene environments might have included ample open spaces richly endowed with perennial grasses. The structural diversity of the Californian Pleistocene megafauna suggests diversified feeding niches, and grazing would have been a major activity. The California flora evolved for millions of years in that milieu. From that perspective, it seems completely natural to experiment with livestock-grazing strategies today. Edwards suggests a model that the ecological needs of present-day grasslands flow at least in part from relations between extinct megafauna and Pleistocene grasses. The amount of adaptive evolution of native grasses since that epoch is no known. However, most present day native bunchgrasses show substantial benefits, in a variety of situations, from grazing, clipping, or fire. Most are tolerant of severe grazing, and some are even tolerant of overgrazing. Climatic change and megafaunal extinctions of the terminal Pleistocene were only the first in a long series of traumas involving California's grasslands. Next came unusually hot dry conditions about 8,000 to 5,000 years ago, the arrival of the Spaniards who brought exotic weeds, excess hunting of elk, installation of fences, overgrazing, fire suppression, and finally elimination of livestock grazing. Overgrazing is not to be blamed for all the loss of native diversity in grassland but often is. Edwards observed a range of current grazing practices in California. Most of his field work shows many and varied examples of native perennial grassland being favored by grazing and/or by frequent fire. In conclusion, Edwards hopes this review would show that livestock grazing can be ecologically beneficial if specific strategies are devised on the basis of site-by-site needs.