Abstract
"The Multi-storied Forest Management Project" is practiced in Perak State, Peninsula Malaysia, as a part of the JICA's project. The purpose of this study is to promote the development of the multi-storied forests by establishing techniques for felling and hauling the upper-story tree, Acacia mangium. To reduce damage to lower-story trees, a backhoe and an agricultural tractor were adopted in the logging system. The labor productivity was 2.36 m^3/person・day in a multi-storied plot, 2.85 m^3/person・day in a four-row plot, and 3.86 m^3/person・day in an eight-row plot. The decrease of the labor productivity by the multi-storied forest management was caused by the difference of a cutting row number. It was estimated that the presence of the lower-story tree did not exert influence as much. Felling, delimbing and bucking costs were estimated at 12 US$/m^3, skidding costs at 7 US$/m^3 and transportation costs at 28 US$/m^3 as a whole. The results of the trial upper-story tree felling and hauling in the survey clearly proved that logging of the upper-story tree would be technically possible. The optimum forest road density in the multi-story forests area was estimated at 26.5 m/ha. However, this density is likely to change considerably depending on the estimated maintenance and administration costs of forest roads ; its cost in the tropical area is a critical factor which will determine the level of any permanent forest road networks for sustainable forest management.
