Simulating Seasonal Trends in Switchgrass Biomass Using Almanac.

An accurate growth model for switchgrass (Panicum virgatum L.) is needed to support decision-making on timing of harvest to predict biomass yield as a function of soil and weather conditions and to maximize resource-use efficiency. The aim was to add a third year of calibration of the ALMANAC model to simulate seasonal changes in biomass yield for Arkansas conditions. Plots were established in 2008 in Fayetteville, AR, with cv. Alamo and were sampled approximately monthly from early May 2009 to mid-February 2010, and again in 2010-2012. Simulations using ALMANAC will be used to test the predictive ability of the model for biomass yield using a calibration from the 2009 growing season. This will indicate whether further calibration is needed to improve accuracy across years.