Recovering sawlogs from pulpwood-size plantation cottonwood

The study explores the possibilities of recovering sawlogs from pulp-size poplar plantations. Under recent short-rotation high-density management practice, only 1.2 percent of the trees reach the minimum size and form requirements for timber production. Separating the sawlogs from the primary pulp chip harvest is technically feasible and requires four additional tasks: selection and marking, separation while forwarding, merchandising, and loading. It also allows saving the cost of delimbing-debarking-chipping. At present, separation costs $42 per green ton, which makes separation profitable. What’s more, there is a potential for halving this figure if the harvesting system is improved according to the findings of the study. The most expensive task is marking and selection, which is performed manually; at present this work accounts for 72 percent of the separation cost. Furthermore, a more flexible merchandising strategy may be needed. Limiting sawlog production to one fixed length means making poor use of the potential yield of the trees; since separation cost decreases with sawlog yield, increasing sawlog recovery provides a substantial economic benefit. Despite its marginal character, the recovery of sawlogs from pulpwood plantations can become economically viable and help differentiate production so as to exploit a wider range of market opportunities. In this context, optimizing the harvesting system is crucial to reaching the appropriate cost and quality goals. © Forest Products Society 2008.