ABSTRACT
Studies on the composition and structure of vegetation can provide important information for decision-making and the application of forest-management techniques. The aim of this research was to analyse an area of Caatinga using vegetation characterisation and forest inventory in the Rocha Eterna Community, in the district of São João do Piauí, Brazil. Simple Random Sampling was used, installing 17 sampling units of 20 x 20 m. The phytosociological parameters of the horizontal and vertical structure, the floristic diversity of the species and the timber production in the area were evaluated. Fabaceae was the most representative family. The three most representative species in the area were Senna acuruensis (Benth.) H.S. Irwin & Barneby, Sideroxylon obtusifolium (Roem. & Schult.) T. D. Penn. and Mimosa tenuiflora (Willd.) Poir. The Shannon-Weaver diversity index (H') for the area was 1.74 nats.ind-1. The estimated basal area for the area was 8.68 m².ha-1. The estimated actual volume was 36.56 m³.ha-1. Species diversity in the fragment under study was considered low.