Tree measurement data from C45 spacing and species mixtures trials, Wind River Experimental Forest

Five units of old-growth were clearcut circa 1980 on Trout Creek Hill, Wind River Experimental Forest in southwestern Washington to establish new stands relevant to management questions in young growth stands. Spacing trials (1x1 or 2x2 meter (m) for the closest spacings up to 6x6 m for the widest spacing) were planted from 1979 to 1982 for Douglas-fir, western white pine, noble fir, western redcedar and western hemlock. In addition, mixtures of various species combinations (50/50 or 33/33/33) were planted at 3x3 m spacing. All treatment plots were 0.4 hectares in size. Permanent measurement plots were established and trees tagged. Many of these plots have been measured several times between 1989 and 2014 for basic tree measurements such as height, diameter, height to live crown, and crown width as well as tree condition metrics such as survival, relative competitive status, and damage to foliage or stem.
The initial goal for this study was to document tree growth response of tree species to initial spacing. Over time we also assessed competition to individual trees from other trees or shrubs so those variables could be used in analyses.
The western redcedar was heavily browsed on most plots and the western hemlock stock did not do well when planted on exposed sites.