Shrinkage of Scots pine wood as an effect of different tree growth rates, a comparison of regeneration methods

The Scots pine (Pinus sylvestris Linnaeus) is one of the most important commercial tree species in Central Europe, yet we know very little about the variability of its wood properties. The aim of this study is to primarily analyse the impact of different tree growth rates and site characteristics on the shrinkage of Scots pine wood. The investigated forest stands are located at two sites of the Czech Republic that are characteristic for Scots pine silviculture. At each site, sample trees were selected from two stands representing two variants of the silvicultural treatment, i.e. a clear-cutting and shelterwood system with long regeneration period. Wood shrinkage in radial and tangential directions and volumetric shrinkage were determined in accordance with Czech standards. Lower values of shrinkage were found out in forest stands regenerated by the shelterwood method. The wood in the central part of the trunk shows lower shrinkage values than in the basal part in both stands. The unambiguous effect of the horizontal position in the trunk stem was demonstrated in forest stands regenerated by the clear-cutting method, whilst stands regenerated by the shelterwood method showed a more even distribution of shrinkage along the trunk width. Furthermore, it was found that the shrinkage of the Scots pine has a medium dependence on wood density.