Grazing management and vegetation response

Abstract

Conventional ecological theory holds that grazing by livestock reduces productivity and alters botanical composition of rangeland plant communities. Changes in composition from that of the “climax” community are considered to be detrimental, but it is usually assumed that these changes will be reversed when grazing animals are removed. Reducing stocking rate and alternating periods of rest and grazing are attempts to mitigate undesirable effects of grazing. Recent research indicates that range ecosystems may retain their productivity and composition when grazed by livestock at seasons and stocking rates which resemble the grazing patterns under which the ecosystems evolved. Weather and fire may have more effect than grazing on productivity and composition, or may interact with grazing. In ecosystems with long-lived woody perennials, changes in composition may be reversible only after centuries or not at all. Finally, communities at early seral stages or communities including introduced plant species may be more productive than climax communities. All these findings indicate that protection of soil and maintenance of stable plant communities at whatever stage of succession may be more reasonable goals of grazing management than efforts to produce and maintain climax communities.