Matisons, R.*, Adamovičs, A., Jansone, D., Bigača, Z. and Jansons, Ā. 2018. Climatic Sensitivity of the Top-Performing Provenances of Scots Pine in Latvia. Baltic Forestry 24(2): 228-233.

   Provenance experiments are established to assess growth of diverse population in novel environmental conditions. Productivity has been the main trait for quantification of sufficiency of the provenances under current conditions. Information on climate-growth relationships can provide deeper insight regarding growth potential, especially considering climatic change. In this study, sensitivity of tree-ring width of two top-performing provenances of Scots pine originating from Northern Germany rowing in two trials differing by continentality in Latvia was assessed. Tree-ring width of both provenances was affected by climatic factors, yet the sets of significant factors differed between stands and provenances. Under milder climate, both provenances were sensitive to temperature in December and temperature in July, suggesting effect of cold damage and water deficit. The less productive provenance (Rostock) was additionally sensitive to conditions in winter. The specific climate growth relationships suggested that the more productive provenance (Neubrandenburg) was able to benefit from longer vegetation season. Under harsher climate, both provenances showed similar growth patterns and were sensitive to conditions in spring and preceding summer, which affect nutrient reserves. The provenance-specific responses were less pronounced. Rostock provenance was additionally sensitive to temperature in April, while Neubrandenburg provenance benefited from warmer summers. Considering the observed climate-growth relationships, the Neubrandenburg provenance appeared more suitable for wider application.

Keywords: provenance trial, Pinus sylvestris, tree-rings, dendroclimatology, tree growth, transfer