We investigated the demography and spatial pattern of an old-growth longleaf pine population using a large plot in which all trees of at least 2 cm in dbh were mapped and tagged for individual recognition. The population was of uneven age and size; tree size correlated positively with tree age. Large or old trees were only loosely aggregated, forming a background matrix that filled the forest. In contrast, juvenile trees were highly aggregated and were located in areas of low adult densities. Recruitment within this population thus appears to occur primarily within open spaces created by the deaths of large trees. Variable time lags may occur before the colonization of open spaces, however, because of temporal variation in seed production and the occurrence of summer ground fires. The absence of large gaps within the age-class distribution indicated that recruitment within the mapped plot has occurred frequently for at least the past 250 years. Neither age- nor size-class distributions, however, were stab...