Small-diameter trees used for thermomechanical pulps

During the course of restoring and maintaining ecosystem health and functio n in the western interior of the United States, many small-diameter stems a re removed from densely stocked stands. These materials are considered nonu sable or underutilized. Information on the properties of these materials is needed to help managers understand when timber sales are a viable option t o accomplish ecosystem objectives. Pulp is a logical use for small-diameter material. Thermomechanical pulps (TMPs) were prepared and evaluated from (a) lodgepol e pine and mixed Douglas-fir-western larch sawmill residue chips, (b) lodge pole pine, Douglas-fir, and western larch submerchantable logs, and (c) lod gepole pine, Douglas-fir, and western larch small trees. TMPs prepared from Douglas-fir and lodgepole pine small trees had equal or better paper prope rties than pulp from sawmill residue chips of the same species. TMPS prepar ed from Douglas-fir, western larch, and lodgepole pine submerchantable logs and western larch small trees had lower paper properties than pulps from s awmill residue chips of the same species. Thermomechanical pulps prepared f rom lodgepole pine submerchantable logs and western larch small trees had t he poorest properties of the eight raw materials evaluated.