The Washington State Department of Natural Resources is commercially thinning naturally established 40-year-old Douglas-fir (Pseudotsuga menziesii) stands which were once considered too small to be merchantable. Efficient, cost-effective thinning is accomplished by whole-tree chipping in the woods. The logging system includes a portable chipper, a chain-flail delimber, two rubber-tired grapple skidders, and three rubber-tired or tracked tree-to-tree feller-bunchers with accumulators. This system provides total utilization of the harvested material. An average of 100 to 125 green tons of pulp chips with less than 7-percent bark can be produced in an eight-hour shift. Approximately 1,000 stems per acre, averaging 4 inches in diameter at breast height, are removed to leave 200 of the best trees. This stocking gives adequate growing space and provides operational maneuverability. The feller-buncher operators are trained to select trees by following rules that describe leave trees. Stand damage can be kept within acceptable limits, preferably under 5 percent of the leave trees, by requiring prelocated skid trail systems and rub trees. Successful tree selection and avoidance of stand damage depend upon operator cooperation.
Document Type: Journal Article
Assistant Division Manager, Research, Forest Land Management Division, State of Washington Department of Natural Resources, Olympia 98504
Publication date: April 1, 1983
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The Journal of Forestry is the most widely circulated scholarly forestry journal in the world. In print since 1902, the Journal has received several national awards for excellence. The mission of the Journal of Forestry is to advance the profession of forestry by keeping forest management professionals informed about significant developments and ideas in the many facets of forestry: economics, education and communication, entomology and pathology, fire, forest ecology, geospatial technologies, history, international forestry, measurements, policy, recreation, silviculture, social sciences, soils and hydrology, urban and community forestry, utilization and engineering, and wildlife management. The Journal is published bimonthly: January, March, May, July, September, and November.