Potential for enhanced properties of wood products by hot water extraction of low-value, undebarked Ponderosa Pine

Suppressed-growth, small diameter Ponderosa Pine stands represent a significant wildfire hazard, but harvesting costs to reduce the hazard are high. These costs can be offset by the value of the timber removed, but these trees are considered low-value. Hot water extraction of undebarked Ponderosa Pine wood chips at 160ºC for 90 minutes showed a mass removal of 20%. Biorefinery technology provides a means of separation and recovery of valuable chemicals from the extract stream. Extracted wood chips showed a 23 - 29% reduction in equilibrium moisture content at 50% RH. Extraction also reduced the inorganic ash content by nearly ⅔; (61%). Reducing the hygroscopicity and inorganic content of the undebarked wood has the potential to impart significant improvements to the production and properties of various wood products. These benefits may provide the economic means for fire-reduction harvesting by converting a low-value wildfire hazard into relatively valuable wood products.