Beschreibung:
Volume yield to mid-rotation in pure and mixed sown stands of Scots pine and Norway spruce was investigated in an experiment in central Sweden. The 43-year-old stands were situated on a 7-ha site and were treated and inventoried at the time of establishment, then at intervals in the life of the stands, to give results at half-rotation age. The dynamics of the mixed stands implied a favourable ecological mixed-stand effect on the height growth of spruce in early development and before crown closure. Even at this stage, pines were taller than spruces, but height was not influenced by admixture with spruce. Pines continued to grow faster than spruces in both height and diameter, resulting in dense mixed stands with dominant pines and co-dominant or suppressed spruces. Diameter of pines was increased by weaker competition for nutrients, while weaker competition for light led to a lower height of dominant pines in mixed stands than in pure pine stands. The results indicate a slight etiolation effect of competition for light in the crown layer. Total volume yield was ...