Vigor of Idaho Fescue Grazed under Rest-Rotation and Continuous Grazing

Abstract

The vigor of Idaho fescue in northeastern California was compared on plots grazed by two different approaches: one full 5-year cycle of rest-rotation grazing, at Harvey Valley; and repeated continuous grazing, at Grays Valley. Vegetative shoot lengths and numbers of flower stalks served as indicators of vigor. Vigor was higher on the Harvey Valley plots. The full-use treatments of rest-rotation grazing did not measurably reduce vigor, nor did the rest treatments improve it. Production of flower stalks appeared to depend on adequate spring precipitation and was not synchronized with the seed production phase of rest-rotation grazing. Continuous grazing at moderate intensity did not reduce plant vigor during the 5-year study period on the Grays Valley plot. The results suggest that moderate, continuous grazing permits Idaho fescue to maintain its vigor. But because rest-rotation grazing disrupts an apparent relationship between grazing use and precipitation, it may hold Idaho fescue vigor at a higher level than can continuous grazing.