Determining environmental conditions of population origins and gardens
We accessed Daymet daily meteorological data for the past 38 years (1980-2018) at each site via the daymetr package in R(Hufkens, Basler, Milliman, Melaas, & Richardson, 2018). Daymet data are 1km2 gridded estimates of daily weather variables, interpolated from weather station data(Thornton et al., 2018). Using these data, we calculated common descriptive climate variables that represent the temperature and aridity of our genotype provenances and 2 common garden sites. All climatic variables we calculated were highly colinear, thus we used a PCA analysis to describe the major axes of variation via the vegan v.2.5-3 package in R (Oksanen et al., 2018) (Figure 2A).