This file contains genotype data for 499 P. trichocarpa and 10 P. balsamifera accessions genotyped with a 34K SNP chip previously described in Geraldes et al 2013: “A 34K SNP genotyping array for Populus trichocarpa: Design, application to the study of natural populations and transferability to other Populus species.” Molecular Ecology Resources, 13(2):306-23. Details for all accessions genotyped can be found in Supplementary table 1 of “Landscape genomics of Populus trichocarpa: the role of hybridization, limited gene flow and natural selection in shaping patterns of population structure” acceptef for publication in Evolution on July 8th 2014. This data file is a matrix with each locus in a row and each accession in a column. Genotypes are given in Illumina’s Forward strand as exported from Illumina’s GenomeStudio software. The numerical value after each genotype is the Genotype Call score. Loci with GenTrain score <0.5 were considered failed assays and were not exported. The file contains data for the remaining 33,070 loci genotyped.