SIMULATING 'ALAMO' SWITCHGRASS WITH THE ALMANAC MODEL

Authors: Kiniry, James; SANDERSON, M - TAMU RES EXT CTR; Williams, Jimmy; Tischler, Charles; HUSSEY, M - TAMU; OCUMPAUGH, W - TX AGRIC EXP STATION; READ, J - TAMU AGRIC RES EXT CTR; VAN ESBROECK, G - TAMU; REED, R - TEXAS TECH

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary: Computer simulation models for forage yield would be valuable for making management decisions. The objectives of this study were to derive values to predict switchgrass yields with a model called ALMANAC and demonstrate how accurately the model simulates switchgrass yields across a wide range of environments in Texas. Plant parameters included leaf area index, dry weight growth per unit intercepted light, optimum nutrient concentrations, and base temperature. The model reasonably simulated yields when harvests occurred either once or twice per season at six diverse sites in Texas in 1993 and 1994. ALMANAC shows promise as a management tool for this important forage and bioenergy crop.

Technical Abstract: A model for forage yield, with adequate details for leaf area, biomass, nutrients, and hydrology would be valuable for making management decisions. The objectives of this study were to develop switchgrass (Panicum virgatum L.) parameters for the ALMANAC model and demonstrate its accuracy across a wide range of environments. Derived plant parameters included leaf area index (LAI), potential biomass growth per unit intercepted light, optimum nutrient concentrations, and growth responses to temperature. The model reasonably simulated 1-cut and 2-cut harvest systems for data sets of cultivar 'Alamo' from six diverse sites in Texas in 1993 and 1994. The model's simulated yields were generally insensitive to potential LAI, heat units to maturity, and radiation use efficiency. ALMANAC shows promise as a management tool for this important forage and bioenergy crop.