DOI: 10.5061/dryad.ch720
title: Data from: Bud phenology and growth are subject to divergent selection across a latitudinal gradient in Populus angustifolia and impact adaptation across the distributional range and associated arthropods

description: Temperate forest tree species that span large geographical areas and
 climatic gradients often have high levels of genetic variation. Such
 species are ideal for testing how neutral demographic factors and
 climate-driven selection structure genetic variation within species, and
 how this genetic variation can affect ecological communities. Here, we
 quantified genetic variation in vegetative phenology and growth traits in
 narrowleaf cottonwood, Populus angustifolia, using three common gardens
 planted with genotypes originating from source populations spanning the
 species' range along the Rocky Mountains of North America (ca. 1700
 km). We present three main findings. First, we found strong evidence of
 divergent selection (QST &gt; FST) on fall phenology (bud set) with
 adaptive consequences for frost avoidance. We also found evidence for
 selection on bud flush duration, tree height, and basal diameter,
 resulting in population differentiation. Second, we found strong
 associations with climate variables that were strongly correlated with
 latitude of origin. More strongly differentiated traits also showed
 stronger climate correlations, which emphasizes the role that climate has
 played in divergent selection throughout the range. We found population ×
 garden interaction effects; for some traits, this accounted for more of
 the variance than either factor alone. Tree height was influenced by the
 difference in climate of the source and garden locations and declined with
 increasing transfer distance. Third, growth traits were correlated with
 dependent arthropod community diversity metrics. Synthesis. Overall, we
 conclude that climate has influenced genetic variation and structure in
 phenology and growth traits and leads to local adaptation in P.
 angustifolia, which can then impact dependent arthropod species.
 Importantly, relocation of genotypes far northward or southward often
 resulted in poor growth, likely due to a phenological mismatch with
 photoperiod, the proximate cue for fall growth cessation. Genotypes moved
 too far southward suffer from early growth cessation, whereas those moved
 too far northward are prone to fall frost and winter dieback. In the face
 of current and forecasted climate change, habitat restoration, forestry,
 and tree breeding efforts should utilize these findings to better match
 latitudinal and climatic source environments with management locations for
 optimal future outcomes.
description: Arthropod_3pop_analysisArthropod community data from the UT garden 2011. Contains all replicated genotypes from the three local tree populations sampled.Arthropod_9pop_analysisArthropod community data from the UT garden in 2011. Contains 1 randomly chosen replicate of each tree genotype, spanning all 9 tree populations sampled.Climate_dataClimateWNA data corresponding to the source location of each tree genotype collected. Also contains the three garden locations' climate, as "AB", "AZ", and "UT" in the file.3pop_analysisCompressed folder contains all files for the 3-population analyses using all replicated genotypes from the three local tree populations sampled nearest to each plantation location. Within the directory, individual files contain data for each garden (AZ, AB, or UT) in each year (2010 or 2011) for each trait (bud flush, bud set, or height and diameter).9pop_analysis_and_GxE_and_GxEplusClimTRDCompressed folder contains all files for the 9-population analyses using a single replicate of eachgenotypes from all nine tree populations sampled. Within the directory, individual files contain data for each garden (AZ, AB, or UT) in each year (2010 or 2011) for each trait (bud flush, bud set, or height and diameter). These are the datasets used for the GxE and climate transfer distance analyses.