Disappearance of Forage under Short Duration and Seasonlong Grazing

Abstract

A study was conducted in 1982 and 1983 at the Dickinson Experiment Station, North Dakota, in the mixed grass prairie to determine the effects of short duration grazing (SDG) and repeated seasonlong grazing (RSLG) by cattle on graminoid, forb, and half-shrub disappearance. Five range sites were delineated within each grazing treatment and evaluated for forage availability and disappearance. Graminoid disappearance was similar, regardless of grazing treatment, each year of the study. However, forb disappearance (i.e., utilization) increased three-fold in 1982 and more than two-fold in 1983 on the SDG treatment as compared to the RSLG treatment. Half-shrub availability and disappearance were negligible both years of the study. Spatial distribution of grazing among range sites on treatments must be evaluated with caution due to limitations in study design. Treatments were not equal-sized or replicated, and area, productivity potential, and distribution of range sites within treatments varied. Despite these limitations, no consistent pattern of site preference was discernible on either grazing treatment. In addition, a greater stocking rate (75%) and density (1400%) on the SDG treatment did not improve grazing distribution as measured by forage disappearance among the diverse range sites present.