Resistant trees (R = 254) and susceptible trees (S = 260) were located and positions mapped in six US states and nine stands. Trees in Penobscot county (Maine), Berkshire county (MA), Randolph county (WV) and Pascataquis county (ME) and two Canadian provenances: Prince Edward Isl. Canada, Kings county, and Sissiboo Falls, Digby county (NS) were located and mapped as reported in previous studies [18, 22]. Additional trees were located and mapped in Ludington State Park, Mason county (MI), Luce county (MI), Mckean county (PA), Clearfield county (PA), Clinton county (PA) and Licking county (OH) (Fig. 1).Fig. 1Sampling locations of mapping population. Highlighted by red full circles are sampling locations of American beech full-sib individuals used for association mapping study across stands in six U.S. states and two Canadian provinces. The map graphic was reproduced in the package ‘ggmap’ (Spatial visualization in ggplot2) v.2.6.1 (Kahle and Wickham)  in software R with Google Maps and Stamen Maps. For Fig. 1 a copyright permission was not required