Some native and exotic species, such as Syzygium spp, Dillenia obovata, Pterocarpus indica, Acacia mangium, A. auriculaeformis and Schima wallichii had been planted, but most of these replanted trees were unsuccessful due to the high soil erosion and the competition of weeds such as Melastoma sp., Saccharum procerum, Chromolaena odorata and Cyperus sp. During the sampling period, the landscape along the pipeline transect at KM5 could be described as a weedy field. The second site, KM27, was established in mixed deciduous forest on a relatively drier site than the other two sample sites. The forests at this site were patchy and mixed with different ages of teak plantations (Tectona grandis L.). This landscape could be described as deteriorated forest. The last site, KM44, was established in mixed deciduous forest dominated by bamboo and some deciduous tree species. The PTT also replanted the same forest tree species mentioned in the description of KM5 above at sites KM27 and KM44. At these two lower sites, at the time of this study, the trees had successfully grown for about ten years and were getting to the sapling stage (Table 1).