This study was conducted in a fragment of semideciduous seasonal forest (SSF), located in Sorocaba (SP, Brazil), in order to verify its successional stage and infer from the future composition. Our hypothesis was that the fragment would present regeneration with low diversity of species; with predominance of pioneer species of canopy and absence of resident species in the understory and predominance of anemochoric and autochoric species. We used the parcels method, considering the individuals in three size classes, two of them referring to rhe understory and one to the canopy (1 -< 100 cm; 2 - >100 cm and circumference at soil height <15cm; 3 -> 15cm. We sampled 146 species, and class 2 understory species presented the highest diversity levels. The similarity between the three classes was low. Considering the species with the highest importance values, five are pioneer and five are non pioneer. Contesting the initial hypothesis, these characteristics, plus the predominance of the zoochorich species in the three species, indicate that the fragment is in an intermediate stage of succession and has microclimatic conditions that allow the entrance and presence of species that need areas with more shadow. Species like Aspidosperma olivaceum, Cordia trichotoma, Ocotea elegans and Guarea guidonia, considered as non pioneer and transitory species, were sampled only in classes 1 and 2, which shows the future species replacement and the sucessional progress of the fragment.
Natural regeneration; Secondary sucession; Understory
