Fig. 2: P. angustifolia and backcross trees from populations climatically similar to the common garden have higher survival.

Mortality of Populus angustifolia and backcross trees (i.e., the percentage of trees from each population that died between 1991 and 2022) increased as both A geographic distance and B climatic distance (i.e., the absolute value of the difference in mean annual temperature (MAT) between the common garden and source population) increased. Individual data points have been jittered vertically to increase visibility. C A map of showing the location of the common garden (green star) and the populations from which the trees were collected. Orange dots indicate populations from which all four cross types were collected, while blue dots indicate populations from which only P. angustifolia and backcross trees were collected. Map in C was created using the Open Source Geospatial Foundation Project through QGIS Geographic Information System (2024).