Seasonal Changes in Herbage and Cattle Diets on Sandhill Grassland

Abstract

The chemical composition and dry matter digestibility of clipped plant species, total herbage, and actual and simulated cattle diets were studied on sandhill grassland in eastern Colorado during the growing season and after dormancy. Clipped plants declined in percent protein and digestibility and increased in other chemical components with advanced maturity. Marked differences in chemical composition were evident among species in early summer, but minimal by winter. Actual cattle diets and those simulated from hand clipped plants were similar in chemical and digestible dry matter composition during each sampling period. In early summer, cattle diets were considerably higher in quality than total herbage but this difference became progressively smaller later in the summer. During dormancy and after weathering chemical composition and dry matter digestibility of herbage and of the cattle diets were essentially the same.