The pairwise clustering based on identity-by-state (IBS), revealed high correlation among individuals in the sample population. The IBS test allowed the removal of individuals with the highest number of correlated “partners”, indicating high likelihood of relatedness. Our method of choice was to test for population outliers by performing IBS-based nearest neighbor analysis. In total, 179 individuals from the five different stands were identified as possible very close relatives and were removed from the further downstream analysis (Table 5).Table 5Duplicated individuals revealed by IBS test for the threshold (IBS > 0.1875)StandNumber of excluded individualsDisease statusLudington State, MI1RNABerkshire county, MA189R9SPenobscot county, Maine5533R22SRandolph county, WV3826R12SSissiboo Falls, Digby county, NS-Canada6527R38SNot classified2NA2STotal179