Abstract
Effects of stand density on the tree growth were investigated in four different planting plots (2,500, 4,500, 7,000 and 10,000 trees per hectare). The height and diameter growth of trees in high density plots (7,000 and 10,000) were greater than those in low density plots (2,500 and 4,500). These differences seem to be caused by the reduction of undergrowth which was dominated by Miscanthus sinensis in the low density plots. Clear bole lengths of trees in the high density plots were also greater than those in the low density plots, therefore the stem taper rate (DBH/DSB: DBH; Diameter at breast height, DSB; diameter at stem base) in the high density plots were greater than those in the low density plots. Furthermore,the rate of crooked trees in the low density plots were greater than those in the high density plots. These results suggest that optimum density for planting Zelkova serrata trees is more than 7,000 trees per hectare
