Regeneration ecology of the bamboo climber Flagellaria guineensis in the Transkei Coastal Forests, Eastern Cape, South Africa

Abstract

Economic benefits obtained from Flagellaria guineensis, a climbing bamboo, by local people received attention in previous studies but little is known about its regeneration ecology in three different forest stand conditions, i.e. forest edges, forest gaps and mature closed-canopy stands. In the Eastern Cape of South Africa the species grows in the Transkei Coastal Forests. The main aim of this study was to assess the regeneration ecology of F. guineensis in those forests. The specific objectives were to describe the phenological state that would influence the flowering, fruiting and growth of the species, and to compare the culm (stem) development from the rhizome between the different forest stand conditions. Phenological comparison was done in forest edge and forest interior conditions two forests. Rating scales were applied to determine the phenological states of the presence and amount of flower buds, open flowers, fruits, shoots and seedlings. Development of F. guineensis was assessed by sampling clusters in the three different forest stand conditions in three forests. The observation made in two Transkei Coastal Forests indicate that F. guineensis regenerates by producing seed, new vegetative shoots from rootstocks and also shoots at the growing tips. The flowering and fruiting period occurred only in the rainy season in Mtambalala forest but both rainy and dry seasons in Bulolo forest. More flowers and fruits of F. guineensis were found in Bulolo forest and in the forest edge (where F. guineensis is able to form tangles on the canopy of its host tree) respectively. This climbing bamboo clings on any plant around it for support and forms tangles on the canopy of its host in forest edges with no direct damage caused to host trees. The production of seedlings, shoots from the rhizome and shoots at the growing tips was constant during the study period in both study sites. The growth pattern of F. guineensis was different when comparing the three Transkei Coastal Forests studied. Manubi forest was found to have clusters and culms with the highest diameters and length compared to Mtambalala and Mnenga forests. There was a significant difference in culm diameter and length of F. guineensis between all three forests, whereas cluster diameter and number of culms per cluster were not influenced by forest stand conditions. F. guineensis clusters were common in the forest edges or gaps, and formed tangles in the canopy of their host trees. The described pattern of growth of F. guineensis contributes to recovery of the forest edges or gaps by restricting easy movement in and out of the forests. Several recommendations were made for harvesting of culms for basketmaking, such as: it should be done with care to reduce tangles in the forest and tree canopies; it must take place during the dry season, when the culms in a cluster are not flowering or fruiting; and studies are needed on the growth rate of seedlings and their growth into the forest canopy and how the bamboo can be cultivated outside the forest for better production of culms.