Table 2 Population structure of Anadenanthera colubrina (Vell.) Brenan, in the rural community of "Riachão de Malhada de Pedra", municipality of Caruaru (Pernambuco, Northeastern Brazil. A1 = more distant study site; A2 = closer study site. The different letters indicate significant differences in the Kruskal-Wallis test (p < 0,05). X = Average, SD = Standard Deviation