EFFECTS OF GIRDLING ON WOOD PROPERTIES AND DRYING CHARACTERISTICS OF <em>ACACIA</em> <em>MANGIUM</em>

Abstract

Basic properties and drying quality of 9-year-old Acacia mangium wood from plantation of the Forest Research and Development Agency in Bogor, Indonesia were studied in order to evaluate effects of girdling periods (0, 4 and 8 months) applied before cutting the trees. Results showed that 8 months of girdling resulted in 50.8% reduction in initial (green) moisture content of wood i.e. from 122 to 60% with no occurrence of end splitting in logs during felling. In general, wood quality of girdled tree is better than that of non-girdled tree. Wood density and holocellulose content increased, while tangential and radial shrinkage ratio, ash, silica, lignin, wood pentose and extractive contents decreased. Based on drying characteristics, basic drying schedule for 8-month-girdled wood was at temperature of 50–80 oC and relative humidity of 80–28%, while that for 4-month-girdled wood and control, temperature of 40–65 oC and relative humidity of 83–38%. The longer girdling period also decreased the percentage of honeycombing and degree of deformation during drying.