Seasonal Trends in Herbage and Nutrient Production of Important Sandhill Grasses

Abstract

Aboveground biomass and nutrient production of important grasses were estimated on two range sites in the eastern Colorado sandhills. Apparent seasonal net production of blue grama and western wheatgrass on the sandy plains site was 144 g/m2 compared to 90 g/m2 for blue grama, prairie sandreed, and needleandthread grasses on the deep-sand range site. Production rates for the grasses studied were 1.8 and 0.8 g/m2/day for the sandy plains and deep-sand range sites, respectively. Herbage biomass decline 28% from the peak standing crop to fall (October 2) on both sites. During the late summer and winter months the biomass declined 50% on the deep-sand site and 35% on the sandy plains site. The sandy plains site produced a larger amount of crude protein than the deep-sand range site. This was accounted for by a larger herbage biomass and a higher percentage of crude protein in grasses grown on the sandy plains site. This more productive site appears to retain more herbage of higher nutritive value throughout the winter than the deep-sand site.