PHENOLOGY OF TIMBER TREE SPECIES IN A BOLIVIAN DRY FOREST: IMPLICATIONS FOR FOREST MANAGEMENT

Abstract

The phenology of 17 timber tree species was observed in a semi-deciduous dry forest in the Lomerio region of Santa Cruz, Bolivia, during two years to obtain biological information useful for forest management. Flowering, fruiting, and leaf fall of 162 individual mature timber trees of the 17 species were observed monthly. Although phenological patterns differed between years, most trees were leafless from June through September coinciding with the middle to late dry season. The majority of species also flowered during the dry season. Peak fruiting occurred just before the beginning of the rainy season and the greatest percentage of species fruited in August and September during both years. This is also the period when most forest harvesting is conducted. Better
coordination of harvest timing with seedfall will increase seed rain onto areas with increased light and scarified soils and may help maximise regeneration success. All but two species studied had wind-dispersed seeds indicating the importance of leaving productive seed trees dispersed throughout this forest. The periodicity of seed production varied widely among species. However, averaged over all species, only approximately one-third of mature trees produced seeds in either year of this study. Therefore, for most species, many more seed trees need to be retained than would normally be required if all trees produced an annual crop of seeds.