Relation of initial spacing and relative stand density indices to stand characteristics in a Douglas-fir plantation spacing trial
This report presents updated information on a 1981 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) plantation spacing trial at 33 years from planting. Stand statistics at the most recent measurement were compared for initial spacing of 1 through 6 meters and associated relative densities. There was no clear relationship of spacing to top height. Diameter, live crown ratio, and percent survival increased with spacing; basal area and relative density decreased with increase in spacing. Volume in trees ≥ 4 cm diameter was greatest at 2 m spacing, while utilizable volume (trees ≥20 cm dbh) was greatest at 4 m spacing. Live crown ratio decreased and total crown projectional area increased with increasing relative density indices. Total crown projectional area was more closely related to relative density than to basal area.
Citation Information
Publication Year | 2016 |
---|---|
Title | Relation of initial spacing and relative stand density indices to stand characteristics in a Douglas-fir plantation spacing trial |
Authors | Robert O. Curtis, Sheel Bansal, Constance A. Harrington |
Publication Type | Report |
Publication Subtype | Federal Government Series |
Series Title | Research Paper |
Series Number | PNW-RP-607 |
Index ID | 70173842 |
Record Source | USGS Publications Warehouse |
USGS Organization | Northern Prairie Wildlife Research Center |