Extrapolating sampled biomass characteristics to whole stalks. (A) S. bicolor stalks were assumed to approximate a conical frustum allowing a simple volumetric calculation. (B) The fourth internode from the base of the plant that had expanded more than 2 cm was harvested and the height (H), stalk radius at the base (R) and top of the stalk (r), the height to the bottom of the fourth internode (H
), and the length of the fourth internode (L) were recorded. Fresh weight (FW), dry weight (DW), sucrose, glucose, and fructose concentrations of pressed juice and digestibility of the lignocellulose were measured in the fourth internode at approximately 10 days post-anthesis. Using the volumetric ratio (V
), these measurements were extrapolated to whole stalks and compared to equivalent measures taken from the same whole stalk. (C) The ratio of extrapolated fourth internode measures to whole stalks (IN/WS ratio), their correlation (r), and the error in prediction (RMSEP, %) are tabulated. DW, dry weight; FW, fresh weight; RMSEP, root mean squared error of prediction.