Experiences with logged forest enrichment through rattan planting in Sabah (Malaysia)

In 1987, Innoprise Corporation Sdn Bhd (ICSB) embarked on a large-scale project for the enrichment of a logged-over forest through planting rattan. In 1989, CIRAD-Forêt joined the project to bring scientific assistance to the research on rattan silviculture and genetics. The method consisted of rattan line plantings under loggedover forest. This system showed some limitations, mainly due to the lack of control on competitors (such as surrounding trees, bamboo and lianas) and on environmental variability (extremely large at the site), that resulted in rattan stands with heterogeneous growth. Studies of the effect of environmental variability on rattan growth, and of methods to control it, began in 1994. A first study focused on the correlation between rattan growth and a number of environmental variables. The results showed that competition from surrounding dipterocarp trees was the main factor in the variability of rattan growth. It allowed definition of which forest types are most suitable for rattan enrichment. Another study focused on the effect of light on rattan growth. Trials were established both in the nursery and in the field. The nursery trials showed that each rattan species has special requirements in terms of light. The field trials allowed quantification of the gain in rattan growth that can be obtained through shade adjustment interventions. Both these studies provided important information to the ICSB's rattan project for improved planting management. (Résumé d'auteur