The Effects Of Height, Radial Position, And Wetwood On White Fir Wood Properties


  • W. Wayne Wilcox
  • W. Y. Pong


Critical measurements and location of externally detectable defects were determined for 20 white fir [Abies concolor (Gord. and Glend.) Lindl.] trees. Boards sawn from these trees were identified with regard to tree, height above ground, and radial position within the stem. Size and location of defects, and grade and drying sort of each board were also recorded. Moisture content, specific gravity, toughness, shrinkage, and liquid absorption were determined on samples taken at three heights and three radial positions from eight of the trees. The data indicated that the sinker sort (the one requiring the longest drying time) came primarily from the center portion of the lowest two 16-ft logs, while the corky (the one requiring the shortest drying time) and sap sorts were, respectively, from the center and outer portions of logs above the second 16-ft log. Approximately 43% of the board volume came from the lowest 32 ft of stem. The highest values of moisture content, specific gravity, tangential and radial toughness, and tangential and radial shrinkage generally occurred in the butt log, decreasing with height, and in the outer third of radial position, decreasing with approach toward the pith. Longitudinal shrinkage was lowest at the butt and increased with height. Because most typical wetwood symptoms occurred in the center of butt logs, it is concluded that, except for the association with drying time, wetwood has little or no detrimental effect on those white fir wood properties investigated.


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