Growth characteristics and wood properties of planted Dryobalanops beccarii Dyer at a reforestation site with girdling treatment of pioneer trees in Sarawak, Malaysia

Abstract

Dryobalanops beccarii is an important species for reforestation and produces durable timber in tropical regions. A reforestation site planted with D. beccarii was established in Sarawak, Malaysia, in 2005, where logging and shifting cultivation had previously occurred. To promote D. beccarii growth, a selective girdling silviculture treatment (debarking below breast height) was experimentally applied to the most dominant pioneer trees, Macaranga gigantea in 2012. In this study, the growth characteristics (stem diameter and tree height) and wood properties (basic density and compressive strength parallel to the grain) of 20-year-old D. beccarii were investigated approximately a decade after the girdling treatment. D. beccarii trees grown in the girdling plot exhibited (1) significantly greater stem diameter and tree height, and (2) similar basic density and compressive strength compared with those in the control plot. In addition, trees with faster radial growth had higher basic density and compressive strength in D. beccarii. These findings indicate that the girdling treatment of pioneer trees can enhance the growth performance of planted D. beccarii without deteriorating its wood quality.