The 187 F1 hybrids (H. tuberosus × H. annuus) and 18 H. tuberosus parents were field grown in St. Paul (2009 and 2010) and Rosemount, Minnesota (2010). Plants were grown in a randomized complete block design with three replications per environment. The two environments were separated by approximately 35 km and differed in climate and soil: St. Paul (located at 45°00′ N 93°05′ W), has a soil type of fine-silty over sandy or sandy-skeletal, mixed, mesic Typic Hapludolls, and Rosemount (located at 44°44′ N 93°01′ W), has a soil type of a well-drained Waukegan silt loam (fine silty over sandy, mixed mesic Typic Hapludolls). F1 hybrids were transplanted as young plants newly emerged from tubers in May in both St. Paul 2009 and Rosemount 2010 from a living collection maintained in St. Paul. F1 hybrid tubers were harvested from the St. Paul 2009 planting and replanted in a different field in St. Paul in November 2009. All plants were grown one meter apart within rows and 1.8 meters apart between rows. Large tubers were used for planting, as sprouting and survival increase with larger tubers (Kays and Nottingham, 2008). Plants were scored for 13 traits. The traits and phenotyping procedures are outlined in Table 1.