A multi-trait assessment of selected provenances of Scots pine following 50 years of growth on a provenance experiment in Central Poland, in the light of climate change

The unpredictable nature of climate change impacts, e.g. warming producing a latitudinal shift in photoperiod, may modify trees’ rates of survival and capacities for growth. This is also true of the Scots pine ( Pinus sylvestris L.), as one of Europe’s main forest-forming tree species. The best results in the study of tree responses to climate change can be obtained during long-term experiments carried out on provenance trials. Such objects make it possible to precisely determine the growth and adaptation reactions of offspring coming from different soil and climatic conditions to the conditions of the research area. Research of this kind has been conducted by analysing growth in the progeny of 16 different Polish provenances of Scots pine on a single provenance experiment located in the centre of Poland, in an area where annual precipitation is at the rather low average level of 580 mm. The experiment was established in 1966, using a randomised block design with five replicates for each of the tested provenances. In autumn 2015, trees present were monitored and analysis of variance was used for their heights and diameters at breast height, with estimates also made regarding straightness of the trunk, crown width and branching angle. At the same time, ecophysiographic features of the places of occurrence of parent stands for each of the provenances were also analysed, with a quantification of the relationship between the growth traits studied and ecophysiographic features also achieved using PCA, while Ward’s Method of clustering was used to establish provenance groups characterised by multi-trait similarity. In the light of what is known about forecast climate change, it would be possible to transfer progeny of different pine populations, if only from places where levels of precipitation are lower, along with values for the De Martonne aridity index. In practice, Central Poland might play host to the progenies of pines from the western part of the country—as represented here by the Bolewice, Rychtal, Karsko and Gubin provenances. On the other hand, the progenies of pines from stands at higher altitudes will not be suitable for cultivation in lowland locations in Central Poland.