Kazuko Makino

Wood Properties of Young Acacia mangium Trees Planted in Indonesia

Abstract 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 simil...

Growth characteristics, stress-wave velocity, and Pilodyn penetration of 15 clones of 12-year-old Tectona grandis trees planted at two different sites in Indonesia

Tree improvement programs for teak (Tectona grandis) have mainly focused on breeding of trees with superior growth characteristics. However, improvement in wood quality should be included in breeding programs for high yield and high quality timber. In the present study, growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (Py) were measured for 15 clones of 12-year-old teak trees planted at two different sites in Indonesia to clarify the variations in tree growth characteristics, SWV, and Py among clones, their repeatability, interaction between genotype and environment, and correlations between measured characteristics. Significant differences of all measured characteristics were found among 15 clones at both sites. Their repeatability showed relatively moderate to high values in both sites. These results indicate that these characteristics are closely related to genetic factors. Significant interaction between genotype and environment was found in all measured characteristics. In addition, SWV and Py showed lower interaction between genotype and environment than growth characteristics. No significant correlation was found between growth characteristics and SWV. These results suggest that wood properties and growth characteristics of teak trees can be improved by application of an appropriate tree breeding program.

Variation in tree growth characteristics, stress-wave velocity, and Pilodyn penetration of 24-year-old teak (Tectona grandis) trees originating in 21 seed provenances planted in Indonesia

Growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (P) were measured for 21 seed provenances of 24-year-old teak trees planted in Indonesia to characterize variation in tree growth characteristics, SWV, and P among seed provenances. Broad-sense heritability and correlations between the measured characteristics were also determined. Significant differences for all measured characteristics were observed among provenances, indicating that these characteristics are genetically controlled. Broad-sense heritabilities of growth characteristics, SWV, and P are moderate values. These results indicate potential for improving growth characteristics and wood properties of teak trees with the help of breeding programs. Highly significant positive correlations were observed among the growth characteristics, suggesting that they are closely related. In contrast, no significant correlations were observed between the growth characteristics and SWV, indicating that they are independent. We conclude that mechanical properties are also important criteria for selecting plus trees in tree breeding programs. Principal component analysis revealed that seed provenances from Indonesia (Bangilan, Deling, and Randublatung) and India (Malabar and Central Province) have high scores of growth characteristics and SWV.

The Effects of Radial Growth Rate on Wood Properties and Anatomical Characteristics and an Evaluation of the Xylem Maturation Process in a Tropical Fast-Growing Tree Species, Gmelina arborea

Abstract The aim of this study was to evaluate the effects of radial growth on wood properties and anatomical characteristics and to clarify the xylem maturation process in Gmelina arborea. Stem diameter, tree height, and stress-wave velocity were investigated for 54 5-year-old G. arborea trees planted in Indonesia. In addition, radial variations of wood properties (basic density and compressive strength parallel to the grain in green condition) and anatomical characteristics (fiber and vessel morphologies) were investigated for nine trees selected from three different radial growth categories (fast, medium, and slow growing). Stem diameter was positively significantly correlated with stress-wave velocity and compressive strength parallel to the grain in green condition. In addition, compressive strength and anatomical characteristics, except for wood fiber diameter, differed significantly among the radial growth categories. Radial variations of the wood properties and anatomical characteristics gradually...

Stress wave velocity, basic density, and compressive strength in 34-year-old Pinus merkusii planted in Indonesia

The relationship between the growth speed and wood properties of Pinus merkusii was investigated using 34-year-old trees planted in Indonesia in an attempt to promote the establishment of plantation of this species. The trees in the test plot were categorized as fast, middle, or slow growing according to the mean stem diameter and standard deviation in the plot. Five trees were selected from each category to investigate the effects of the growth rate on the wood properties [basic density (BD) and compressive strength parallel to the grain in a 5-mm-diameter core sample (CS)]. No significant correlation was recognized between the stem diameter and the stress wave velocity of trees. Clearly lower values of BD and CS were found in slow-growing trees than in fast- and middle-growing trees. The BD of xylem near the pith was reduced by extraction with organic solvent. BD after extraction and CS gradually increased from pith to bark. The results obtained in this study clarified that an early selection of trees with high BD is possible by using the BD after extraction at 4 cm from the pith.