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Climate change is rapidly transforming high latitude ecosystems, yet comparative growth responses between trees and shrubs at the northern treeline remain understudied. The Arctic and Sub-Arctic, including northern Scandinavia, has warmed nearly four times faster than the global average since 1979, leading to reduced snow cover and earlier onset of the growing season. These shifts highlight the need to understand how different life forms respond to ongoing warming. This study compares the climatic sensitivity of Pinus sylvestris L. trees and Juniperus communis L. shrubs in northern Norway, Øvre Pasvik region, positioned at the Europe’s northernmost treeline. Specifically, we aimed to assess whether the temperature sensitivity of two co-existing woody plant forms at the northern treeline are coherent and stable over time. We developed 385- and 423-year-long tree-ring width chronologies for Pinus trees and Juniperus shrubs, respectively. For both species we analysed their relationships with instrumental climate data: air temperature, precipitation and Standardized Precipitation-Evapotranspiration Index (SPEI, scale =3) for the period 1901–2022. We revealed that Pinus trees maintained strong and stable correlation with July temperatures (r = 0.56), while Juniperus shrubs exhibited weaker July temperature signal (r = 0.35) that declined and became largely non-significant after the 1970s. While increased drought stress is often suggested as a cause for temperature signal loss in high latitudes, this does not appear to be the case in Øvre Pasvik, as correlations between Juniperus shrubs and SPEI are generally weak or negative for the recent period. Additionally, growth of Pinus trees was positively related to May precipitation, while Juniperus shrubs exhibited negative relationship with May precipitation. Our findings highlight reliability of Pinus trees chronology as a temperature proxy at the northernmost treeline. We also underscore the necessity of high-resolution microtomy and microscopy techniques for accurate ring detection in Juniperus shrubs as standard method minimizing the risk of misdating or discarding ecologically valuable material.