Performance and yield of 14 eucalypt species on Imperata cylindrica (L.) Beauv. grassland 3 years after planting

A species trial with 14 eucalypt species with randomized complete blocks design was planted on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia in January 1987. The site was prepared mechanically. No fertilizers were used. At the age of three years E. camaldulensis had clearly the highest survival rate (95%) and mean annual increment (5.9 m³ha^–1a^–1) compared with the other species tried. It was followed by E. urophylla, E. deglupta, E. pellita, E. tereticornis, E. alba, E. torelliana, E. intermedia, E. grandis and E. pilularis. Four other species, E. phaeotricha, E. resinifera, E. cloeziana and E. microcorys died either in the nursery or immediately after planting. All the eucalypts tried had narrow crowns and open canopies. It is suggested that eucalypts are not recommendable for grassland reforestation under minimum plantation tending. Effects of intensive weeding, spacing, fertilizing and performance in second rotation or mixed stands should be tested to elaborate the suitability of eucalypts on grasslands.     

Evaluation of reforestation potential of 83 tree species planted on Imperata cylindrica dominated grassland – A case study from South Kalimantan,Indonesia

Survival and growth of 83 tree species were tested in three separate species elimination trials on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia. The trial layout was randomized complete blocks design with 6–8 replications of 5-tree line plots. At the age of two years exotics, like several Acacia species (A. mangium, A. crassicarpa, A. auriculiformis, A. cincinnata, A. leptocarpa), as well as Gmelina arborea, Paraserianthes falcataria and Cassia siamea had survival rates of 90–100%, crown width of 3–6 m and mean height of 5–8 m. Among the most promising local species were Anthocephalus chinensis, Peronema canescens and Parkia roxburghii but their growth was inferior compared to exotics. Eucalypts and pines were not among the highest ranking trees and cannot be recommended for initial grassland reforestation. At the age of 7–8 years the same species were still dominating, but increasing mortality of several species was observed. Especially Acacia crassicarpa and A. cincinnata of the exotics were affected, and indigenous Anthocephalus chinensis almost perished. Since fast early growth is necessary in first rotation reforestation of grasslands, fast growing exotic species provide a reliable basis for further activities. Final performance of reforestation species has to be confirmed in stand-level experiments and pilot plantations. Intensive work on integrating local tree species in reforestation of grasslands in the long run is recommended.