Climate change is causing frequent and extreme droughts which reflect in the rapid decline of Norway spruce. Douglas fir is an allochthone species that could compensate for the losses due to Spruce dieback. It grows well in our forests but its response to severe droughts is still unexplored. In the following study, we used dendrochronological analysis to compare the response of Norway spruce and Douglas fir to climate factors. Each species was sampled on three sites. We constructed local chronologies and calculated correlations between growth and temperature and precipitation. In addition, we analysed the pointer years. PCA was used to analyse the effect of climate factors on growth. Douglas fir showed a more uniform response to climate. Its growth was primarily positively influenced by high temperatures in February (cold hardiness) and by above-average summer precipitation in the last decade. Summer temperatures and decreased precipitation had a greater impact on Spruce. Analysis of pointer years showed no differences among the two species. We conclude that Douglas fir is a suitable species to replace Spruce if it is planted in suitable sites, as a mixture to indigenous species, with carefully chosen proveniences and tending applied.
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