Forest Residues

Nearly 20 billion cubic feet of wood is removed on an annual basis from lands in the United States. Of that volume, 16 percent is classified as logging residues (Smith et al. 2004). This material is mainly tree tops and small branches that have been considered uneconomical to harvest. The USDA Forest Service Inventory and Analysis program estimates that 61 million dry tons of residuals are available annually from harvesting and fuel reduction activities. A recovery system, that would follow behind a conventional logging operation, could recover 60 percent or 40 million dry tons of this residue for potential bioenergy and biobased product markets (Stokes 1992). To maintain soil properties and nutrients, not all available forest residuals should be recovered during operations (Perlack et al. 2005).

Current Availablity of Logging Residues and Other Removals

Post-logging operations typically result in two categories of waste:

• Harvesting Wastes
• Bark