EARLY GROWTH OF THREE DIPTEROCARPACEACE SPECIES UNDER RUBBER PLANTATION STAND IN COASTAL AREA OF CENTRAL BENGKULU DISTRICT, BENGKULU PROVINCE

The natural vegetation of lowland area of Bengkulu used to be natural forest dominated by Dipterocarpaceae trees, which have high economic value. Currently, however, dipterocarp trees has become rare due to conversion of natural forest into plantation. Many rural people in Bengkulu plant their land with rubber trees. The objective of this study was to monitor the growth of three dipterocarp spcecies, namely Shorea javanica,Shorea macrobalanos and Hopea mengarawan, planted under rubber tree plantation. The study has beenconducted in Pondok Kelapa Village, Pondok Kelapa Sub-district, Central Bengkulu District, Bengkulu Province, Indonesia since February 2015 to May 2016. Pondok Kelapa Village is located on the west coast of Sumatra. Thirty seedlings for each species were planted regularly, with planting distance of 2 x 2 m under Hevea brasiliensis stand. The height and diameter of plants were measured every two months. The data were analyzed statistically to know the difference growth among the three species. Within 14 months, Shorea javanica grew 18 cm in height (115% of the original height) and 2,9 mm (78%) in diameter, Shoreamacrobalanos 31 cm (118% ) and 3,4 mm (79%), and Hopea mangarawan 28 cm (90%) and 3,1 mm(70%). There was no significant difference in height or diameter growth among species. During severe drought of 2015 some seedlings died