The study reports a genetic analysis of growth and stem formation of Eucalyptus pellita in Orinoquia, eastern Colombia. Families from two restricted locations in New Guinea, collected ex-situ in a local arboretum, significantly outperformed four Queensland, Australia provenances for growth and stem formation. Heritability estimates were low for both traits, 0.05-0.10. Correlation between stem straightness and diameter was positive and strong, but null with height despite height and diameter being strongly related. The mixed model used