Logging residue and the biomass in standing residual inventory trees-primarily rough and rotten trees left on harvested sites-offer largely untapped potential as sources for a sustainable supply of biofuel. Rough trees are live trees of commercial species not containing at least one 12-foot saw log, or two noncontiguous saw logs, each 8 feet or longer, now or prospectively, primarily because of roughness, poor form, splits, cracks, and with less than one-third of the gross board-foot tree volume in sound material; and live trees of noncommercial species. Rotten trees are defined similarly, but have less than one-third of gross board-foot tree volume in sound material. This report provides estimates of postharvest biomass in logging residue and residual inventory from timberland acres where tree cutting has occurred.