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Northern hemisphere tree species growing at their northern range margins may be particularly responsive to climate change and could provide important information regarding future broad-scale responses. We analyzed and compared tree-ring data between five Douglas-fir [Pseudotsuga menziesii var. glauca (Mirb.) Franco] populations growing at the species' northernmost distribution in British Columbia, Canada, and five populations located 150 km to the southeast. We quantified climate-growth relationships using uni-and multivariate techniques at different temporal scales. Our data suggest that (1) even at its northernmost distributions, precipitation limits longterm mature Douglas-fir radial growth more than temperatures, (2) northernmost Douglas-fir populations are distinct from populations located further within the species' range in terms of certain key short-term growth responses, and (3) northernmost Douglas-fir growth sensitivities to climate may be increasing over time. In the future, mature Douglas-fir productivity in the northern portion of its range may be primarily limited by precipitation, and responses may be strongest at the species' range margins.