Population-level plasticity drives plant trait variation along elevation

Within a species, plant traits may vary substantially along environmental gradients. However, is such variation (1) consistent across locations and (2) genetic or non-genetic (i.e., plastic) in nature? In a recent ‘Editor’s Choice’ article published in AoB PLANTS, Pfennigwerth et al. combined field observations and a common garden experiment to assess Rhododendron maximum trait variation within and among three elevation gradients. Their findings reveal that trait variation along environmental gradients in this species is (1) highly population-specific and (2) driven primarily by non-genetic factors (i.e., plasticity). Overall, their findings highlight the importance of examining multiple locations and suggest that trait responses to environmental change vary by location.