Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 20, 2009
Publication Date: January 10, 2010
Citation: Robins, J.G. 2010. Cool-Season Grasses Produce More Biomass Across the Growing Season than do Warm-Season Grasses when Managed with an Applied Irrigation Gradient. Biomass and Bioenergy. 34:500-505. Interpretive Summary: Although warm-season grasses have great biomass production potential, their performance has never been documented under irrigated, high-elevation conditions. The results of this study documented the performance of several warm-season grass species when compared to common cool-season grass species at various irrigation levels. Overall, the cool-season grass species were much more productive across the entire growing season. However, when only considering the summer harvests, the warm-season grass species, and in particular, the switchgrass cultivars were more productive. Thus, the cool-season grass species are the best choice for total biomass production across the entire growing season, but switchgrass showed potential as a productive summer forage alternative.
Technical Abstract: Warm-season grasses have shown great potential for biomass production. However, their productivity under irrigated, high-elevation conditions has not been documented. This study evaluated the biomass production potential and production stability of a number of warm- and cool-season grasses across an irrigation gradient at a high-elevation location. Under the multiple-harvest management strategy, the cool-season grasses were most productive across the entire growing season. Nevertheless, when considering only the summer harvests, the switchgrass and big bluestem entries were the most productive, although the lowland cultivar Alamo did not perform well under the conditions. Overall, cool-season grasses were clearly the most productive for total biomass production across the growing season. However, based on the high biomass production of switchgrass, this species may have potential as a high-producing option for animal feed during the summer months when the cool-season grasses are unproductive.