The summative analysis of lignocellulosic materials has heretofore been a complicated process or the analysis has been incomplete. The Bomb/HPLC summative analysis method presented in this report results in a complete analysis of woody materials using a sample preparation scheme that is easily adopted into a normal laboratory routine. The method relies on HPLC for the majority of the component analyses. To demonstrate the applicability and reproducibility of the Bomb/HPLC method, ten wood samples, from nine different wood species, were analyzed in triplicate and the summative analysis of each sample was effected. The ten woods analyzed were: American beech (Fagus grandifolia), Quaking aspen (Populus tremuloides), Black cherry (Prunus serotina), Sugar (Hard) maple (Acer saccharum), Red (Soft) maple (Acer rubrum). White ash (Fraxinus americana), Yellow birch (Betula verrucosa), Douglas fir heartwood and Douglas fir sapwood (Pseudotsuga menziesii), and White fir sapwood (Abies concolor). The average summative analysis for the group of thirty samples was 99.13 ± 0.51% on an unextracted basis, 99.07 ± 0.45% on an extractive-free basis. There were no significant unidentified peaks in any of the HPLC chromatograms. The range of mass balance determinations for the group of ten wood specimens on unextracted and extractive-free bases was 98.43 to 99.63% and 98.31 to 99.60%, respectively.