This study evaluated the wood properties of 5- and 7-year-old Acacia mangium trees planted in West Java, Indonesia. A plot (20 by 20 m) was selected in each stand. The stem diameter and stress-wave velocity (SWV) were measured for all trees (n = 24 and 18 for 5- and 7-y-old trees, respectively) in the plots. Core samples were taken from all trees in each plot using an increment borer to measure the basic density (BD) and compressive strength parallel to the grain (CS). The mean ± standard deviation stem diameter was 13.1 ± 3.0 and 21.9 ± 3.8 cm in 5- and 7-year-old trees, respectively. There was no significant correlation between stem diameter and SWV. The mean BD and CS for 5-year-old trees were 0.42 ± 0.02 g cm−3 and 30.0 ± 4.4 MPa, respectively, and for 7-year-old trees were 0.45 ± 0.02 g cm−3 and 32.8 ± 3.6 MPa, respectively. There was a positive correlation between BD and CS in 5- and 7-year-old trees (r = 0.790 and 0.583, respectively). The radial variation patterns for BD and CS were similar in 5- and 7-year-old trees: BD and CS gradually increased to about 6 cm from the pith, after which it was almost constant toward the bark. The results suggest that xylem maturation depends on the growth diameter in A. mangium.

In view of the importance of long-rotation plantation forestry in SE Asia to limit soil erosion, the cell morphology and wood properties of 35-yearold plantation trees of yellow meranti, Shorea acuminatissima Sym. were studied. To understand the effects of growth rate on cell morphology and wood properties, 131 trees in a stand were classified according to their stem diameter as fast-, medium-, and slow-growing. Five trees in each category were selected for determining the cell morphology and wood properties. There were significant differences in vessel diameter, vessel frequency, and cell wall thickness of wood fibers in the three categories. The fast-growing trees had a relatively low frequency of wide vessels and thick-walled wood fibers. However, no significant differences in basic density or compressive strength parallel to grain were identified in the three categories. The radial variation in the cell morphology and wood properties showed an almost identical pattern in the three categories, suggesting that xylem maturation depends on the cambial age rather than growth rate.

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The growth characteristics, anatomical characteristics, and wood properties of Dysoxylum mollissimum, a fastgrowing tree species, were investigated. To clarify the effect of radial growth rate on these characteristics and properties, 10-yearold trees planted in Bengkulu, Indonesia were examined and classified into three categories (fast-, medium-, and slow-growing). Xylem maturation type was also evaluated in this species. The mean values of stem diameter, tree height, stem volume, and stresswave velocity in the 50 measured trees were 18.0 cm, 10.6 m, 0.119 m 3 , and 3.48 km s 1 , respectively. Mean values of anatomical characteristics and wood properties in nine selected trees were as follows: vessel diameter, 129 µm; vessel frequency, 3.5 vessels mm 2 ; cell wall thickness of wood fiber, 1.2 µm; percentages of vessels, wood fiber, ray parenchyma, axial parenchyma, and cell wall, 8.8, 72.9, 12.4, 5.9, and 33.5%, respectively; vessel element length, 0.36 mm; wood fiber length, 1.04 mm; basic density, 0.45 g cm 3 ; and compressive strength parallel to the grain in green condition, 29.9 MPa. These obtained values were similar to or smaller than previous results obtained in research on other Dysoxylum spp. For almost all of the anatomical characteristics and wood properties, no significant differences among the categories were found. This suggests that the trees with faster radial growth characteristics do not always produce lower quality wood in this species. Judging from the radial variation of anatomical characteristics, the xylem maturation of this species depends on the diameter growth, and it might occur at around 6 to 8 cm from the pith.

The utilization of wood resources from unutilized fast-growing tree species found in secondary forests was investigated by studying the wood properties, including anatomical characteristics, of two Macaranga species-M. bancana and M. pearsonii-growing naturally in secondary forests in Central Kalimantan, Indonesia. Several wood properties related to pulp and paper quality were also evaluated, including the Runkel ratio, Luce＇s shape factor, flexibility coefficient, slenderness ratio, solid factor, and wall coverage ratio. The mean basic density of these two species ranged from 0.23 to 0.31 g cm , while the mean values of vessel diameter, vessel element length, fiber diameter, fiber wall thickness, and fiber length ranged from 126 to 192 µm, 0.88 to 1.19 mm, 24.5 to 29.8 µm, 0.99 to 1.14 µm, and 1.42 to 1.69 mm, respectively. The lignin content of M. bancana and M. pearsonii wood was 27.2 and 28.0%, respectively. Almost all wood properties related to pulp quality showed better values than those reported for Acacia and Eucalyptus species, although sheet density of paper might be lower due to higher solids factor and possibility of occurrence of vessel picking was probably higher due to longer vessel element length and larger vessel diameter. Based on the results, the wood from these two Macaranga species can be used as pulpwood.