Guidelines for Grazing Sheep on Rangelands Used by Big Game in Winter

Abstract

A big game winter range in northen Utah was grazed with domestic sheep to ascertain what seasons and intensity of use would maximize utilization of herbs and minimize utilization of shrubs which provide the majority of forage for big game in winter, thus minimizing forage competition between big game and sheep. In late spring and early summer sheep ate mostly herbs. The light utilization of shrubs resulted in little or no reduction in forage production by shrubs at the end of the growing season. After mid-July, sheep heavily utilized bitterbrush (Purshia tridentata), the most desirable and abundant shrub for big game in this area. Grazing after mid-July reduced the volume of bitterbrush forage available for big game proportionately to the percentage utilization observed. There was no evidence that subsequent annual productivity of established plants was impaired by any of the grazing systems imposed.