Abies grandis (Douglas ex. D. Don) Lindl. productivity in central European provenance trial reflects populations’ adaptation to seed source climate

Ongoing climatic changes and their future projections indicate that native conifer tree species would lose their suitable climatic niches in central Europe by the end of century. Maintaining productivity and carbon sequestration capacity in managed forests may require focusing on alternative tree species, including non-native ones. In this study we investigated productivity traits of seven grand fir (Abies grandis (Douglas ex. D. Don) Lindl.) provenances at two common garden testing sites in Poland to examine the extent at which variation could be attributed to climatic adaptation, and to the response to climatic transfer distances. Productivity per unit land area varied significantly between two sites and among tested provenances. The observed patterns of variation pointed to increasing performance of populations with milder climate and more favorable climatic moisture availability at their origin, indicating adaptation of local populations. Seed sources from Vancouver Island, the Olympic Peninsula, and the Cascades of Washington should be prioritized for planting in conditions of central Europe. The use of grand fir provenances in afforestation and reforestation programs must be closely aligned with climatic matching, especially with respect to moisture availability, for maximizing productivity and enhancing structural diversity of managed forests in central Europe in a changing climate.