Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is a well researched endemic of pacific North America, a 'non-native' conifer with great economic and ecologic potential, successfully introduced into european forests as early as the second half of the 19th century. The interest for it's further introduction is still growing and crucial to it's success is selecting optimal forest reproductive material (FRM). Knowledge to do so can be gained with provenance trial plantations. One of which is Padež II, composed of 11 provenances in 1972 under IUFRO, located in Brkini, Slovenia. The average survival rate in the 51-year-old plantation is 38.9 % with a growing stock of 652.2 m3/ha. Parametric and non-parametric tests were used in finding the differences in growth, vitality and branch characteristics between provenances. One of the most positively deviating provenances is Steamboat, whereas Arcata I deviates negatively. The overall log quality does not go above class C. According to our observations, Western Oregon and higher altitude Northern Californian provenances are best suited for this part of Slovenia, and Detroit has been choosen as the optimal one. In light of predicted climate change, a wider introduction of species, such as Douglas-fir, into Slovene forests should be initiated.
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