| Abstract: | The effects of timing and intensity of precommercial thinning were studied in three Scots pine artificially regenerated stands on Vaccinium forest sites in southern Finland. A two-level factorial design (3×3) was used in each stand: thinning at dominant height of 3, 6 and 9 m to 1000, 1600 and 2200 stems ha?1. The effects of the treatments were analysed after a period of 23–25 yrs when the dominant height was 14–15 m. Early thinning resulted in the highest standing volume and amount of merchantable wood, and also in slightly accelerated height development. Thinning to 1000 stems ha?1 caused a considerable production loss, but there were no differences between the densities of 1600 and 2200 stems ha?1. Branches became thicker after early thinning, but the differences between the treatments were negligible for crop trees. Crown ratio was lowest as the result of early or moderate thinning (2200 stems ha?1). |
