The aim of this study was to evaluate the structure and diversity of the woody component of Caatinga in Southern Sertanean Depression, Petrolina, Pernambuco State, Brazil. We sampled 25 plots of 400 m². Total height and circumference at the soil level (CSL ≥ 15.8 cm) were measured of living or dead standing individuals, to calculate phytossociological parameters. The community heterogeneity was evaluated throug...