To address this issue, experiments were performed to compare ASE and Soxhlet methods for aqueous extraction of representative corn stover, switchgrass, and sorghum samples.  For each extract, the mass percent of water-soluble materials was determined gravimetrically, and sugar composition was determined via high performance liquid chromatography with pulsed amperometric detection (i.e., HPAE-PAD).  Subsequent experiments were performed to evaluate the number of extraction cycles required for “exhaustive extraction” using the ASE approach.  Mean data (n ≥ 3) were compared at the 95% confidence limit, using a t test or F test, as appropriate, to assess statistical differences in mean data.  No statistical differences in % extractives or sugar content were observed among extracts prepared using either the Soxhlet approach or ASE with 2 or more extraction cycles.  This study strongly suggests that use of either extraction approach will result in aqueous extracts of comparable composition for a variety of herbaceous biomass materials.