Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is an important exotic tree species that was planted across a large part of Europe during the last century. In both experimental trials and conventional forest plantations, the trees grow at a high rate and produce high-quality timber. The present study investigated climate-growth relationships of Douglas-fir at two Italian sites that contrast in climate: a Mediterranean area in southern Italy (Mercurella site) and a cooler, moister site in the northern Apennines without summer aridity (Acquerino). The relationship between tree-ring chronologies and monthly climatic variables was evaluated by a moving average and correlation analysis. Results showed that the minimum temperature in February and in March play a key role for Douglas-fir at both sites, with a positive effect on growth. At the northern site, it is also highly sensitive to late summer temperatures (negative correlation) and spring–summer precipitation (positive correlation). Growth rates in southern latitudes were high even in Europe and in the Mediterranean environment, with low sensitivity to climatic fluctuation. On the basis of our results, further common garden experiments should test adaptation and the interaction between genetics and environment of second- or third-generation seeds from old stands across Europe such as done by the old International Union of Forest Research Organizations (IUFRO) or the European Douglas-fir Improvement Research Cooperative (EUDIREC) experimentation programmes.

道格拉斯冷杉（Pseudotsuga menziesii（Mirb。）Franco）是一种重要的外来树种，上个世纪在欧洲大部分地区种植。在实验性试验和常规森林种植中，树木都以高速率生长并生产出优质木材。本研究调查了道格拉斯冷杉在两个气候不同的意大利地点的气候-生长关系：意大利南部的地中海地区（Mercurella地点）和亚平宁山脉北部较凉爽，潮湿的地点（阿奎里诺）。通过移动平均值和相关性分析评估了树木年轮年代与月度气候变量之间的关系。结果表明，2月和3月的最低温度对道格拉斯冷杉在这两个地点均起关键作用，对生长有积极影响。在北部，它也对夏末的温度（负相关）和春夏季降水（正相关）高度敏感。即使在欧洲和地中海环境中，南部纬度地区的增长率也很高，对气候波动的敏感性较低。根据我们的结果，进一步的常见花园试验应测试适应性以及欧洲旧林分第二或第三代种子的遗传与环境之间的相互作用，例如由旧的国际森林研究组织联盟（IUFRO）或欧洲花旗松改良研究合作社（EUDIREC）实验计划。即使在欧洲和地中海环境中，南部纬度地区的增长率也很高，对气候波动的敏感性较低。根据我们的结果，进一步的常见花园试验应测试适应性以及欧洲旧林分第二或第三代种子的遗传与环境之间的相互作用，例如由旧的国际森林研究组织联盟（IUFRO）或欧洲花旗松改良研究合作社（EUDIREC）实验计划。即使在欧洲和地中海环境中，南部纬度地区的增长率也很高，对气候波动的敏感性较低。根据我们的结果，进一步的常见花园试验应测试适应性以及欧洲旧林分第二或第三代种子的遗传与环境之间的相互作用，例如由旧的国际森林研究组织联盟（IUFRO）或欧洲花旗松改良研究合作社（EUDIREC）实验计划。