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The heartwood percentage and wood colour of fast plantation grown teak destined for harvest at 5 years of age were characterized using automatic image processing ’ImageJ’ routines and CieLab’s colour system with the following coefficients: L for lightness, a* for redness and b* for yellowness. Analyses were conducted on material from different dry and wet sites. Comparison with 6-year old plantation from a dry site was conducted to study differences arising in older trees. Analyses of variation of those properties between and within different tree diameter classes were also conducted. The results showed that brightness, redness and yellowness values of 5-year old teak trees were 60.7, 10.7 and 23.1, respectively. Tree clone had a more dominant effect on wood colour and heartwood proportion than site, thus if specific colour preferences are needed of plantation trees, clone selection is important. The drier site produced larger proportions of heartwood in trees, as well as a more attractive figure. The trees produced heartwood proportions of 20% and 14% from the dry and wet sites respectively. On average, these 5 year old teak trees already produced 18% heartwood. Faster tree growth (larger diameter) appeared to have produced significantly larger heartwood proportions. Radially, the palest colour (the highest L but the lowest a*b* parameters) occurred in an area between heartwood and sapwood indicating the presence of a transition zone in all the tree samples.

Wood properties of young teak (Tectona grandis L.f.) is inferior, and then preservative treatment is one possible solution to enhance its service life. The uptake and movement of preservatives through wood cell structure is directly connected to the wood permeability. There are two simple methods to identify wood permeability: water soaking and bubble test methods. This paper assesses the young teak permeability by water soaking and bubble test methods. The assessment was conducted into five cm thick young-teak discs by soaking in the red-dye water and blowing air into the discs which had been coated with soap. Results show that the heartwood is less permeable than sapwood. Red-dye penetrates almost 100% of the sapwood area, and the red-dye did not penetrate in the heartwood. Red-dye only penetrates in the cracked heartwood through the void volume in the cracking heartwood. There is a transition zone between sapwood and heartwood, and it is refractory. Bubble test with air pressure from compressor could open the air-pathway in the heartwood and sapwood of young-teak discs taken from Bogor. The bubble test result of young-teak discs from Madiun showed air-pathway only in the sapwood, but heartwood. The air pressure is not capable of moving the vapour through the wood cell. It indicates that the heartwood of young-teak from Madiun is less permeable and less possibility for pressure treatment.

Wood hardness is an important property for flooring, furniture products and structural utilization. Currently wood hardness can only be measured using destructive testing. As there is no suitable method for predicting wood hardness from standing trees, developing a non-destructive technique to predict wood hardness from plantations trees would provide significant benefits for evaluating optimal silvicultural treatments, and for selecting trees for tree improvement programs. It is proposed initillay that a possible non-destructive test may be developed using „crystallinity“ characteristics (degree of crystallinity (DC), crystalite width (CW) and length (CL) and microfibril angle (MFA)) determined using X-Ray diffraction. The aim of this study was to test the feasibility of using crystallinity as a non-destructive indicator of wood hardness. Experimentally, nine trees were taken representing small, medium and large diameter from five-year old fast growing teak plantation forest in Ciampea, Bogor, Indonesia. Wood hardness and crystallinity were determined following a standard testing regime. The results showed that MFA was negatively related to all hardness directions. Crstallite width only influenced side hardness with negative correlation, while degree of crystallinity only affected the end-grain hardness with positive correlation. Different vertical positions within tree only influenced the end-grain hardness value, while different radial positions had no effect on wood hardness. The optimum sampling height was found to be 80 cm, 130 cm, and 100 cm for radial, tangential and end-grain hardness, respectively. The relationship was based on the height that provided the highest correlation with the whole tree hardness values. Proposed models involving density and „crystallinity“ for predicting wood hardness are presented. While the R2from the proposed models was mostly less than 0.50, however, the approach described provides a new way to predict wood hardness from 10 mm increment cores at standing trees.

Development of optimal ways to predict juvenile wood stiffness, strength, and stability using wood properties that can be measured with relative ease and low cost is a priority for tree breeding and silviculture. Wood static modulus of elasticity (MOE), modulus of rupture (MOR), radial, tangential, and longitudinal shrinkage (RS, TS, LS), wood density (DEN), sound wave velocity (SWV), spiral grain (SLG), and microfibril angle (MFA) were measured on juvenile wood samples from lower stem sections in two radiata pine test plantations. Variation between inner (rings 1–2 from pith) and outer (rings 3–6 from pith) rings was generally larger than that among trees. MOE and MOR were lower (50%) in inner-rings than in outer-rings. RS and TS were higher (30–50%) for outer-rings than inner-rings, but LS decreased rapidly (>200%) from inner-rings to outer-rings. DEN had a higher correlation with MOR than with MOE, while MFA had a higher correlation with dry wood MOE than with MOR. SLG had higher significant correlation with MOE than with MOR. DEN and MOE had a weak, significant linear relationship with RS and TS, while MOE had a strong negative non-linear relationship with LS. Multiple regressions had a good potential as a method for predicting billet stiffness (R 2 > 0.42), but had only a weak potential to predict wood strength and shrinkage (R 2

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The potential for using growth strain measured at the stem periphery of standing plantation-grown Eucalyptus globulus Labill. trees as a non-destructive detection method for tension wood was assessed. Two trials were conducted 12 months apart in a 10 to 11 year-old provenance trial of E. globulus located in the Mt. Gambier region of south-eastern Australia. The relationship between the occurrence of gelatinous fibers over varying radial depths of wood tissue and growth strain measured at breast height was investigated. The percentage of gelatinous fibers in wood tissue laid down in approximately the two years prior to taking the growth strain measurement was found to correlate best with growth strain. In an expansion of this work, growth strain was found to be a good indicator of the presence of gelatinous fibers in wood tissue taken from the immediate position where growth strain was measured. Thresholds were found at approximately 800 ue, above which gelatinous fibers were common, and 1,200 ue where gelatinous fibers were always present in each of the three provenances assessed. Tension wood was found to increase in occurrence over the 12 month period in line with a trend of increasing occurrence and severity of tension wood found in earlier work in the plantation.

Summary The potential for growth strain measurements for detection of tension wood was assessed in trees from two plantations of 10- to 11-year-old Eucalyptus globulus. Tension wood had commonly developed at or near the stem periphery of straight, vertical and dominant trees. At a localized level growth strain was found to be a good indicator of tension wood. However, in some cases moderate to low growth strain was also detected in some trees where tension wood had been overgrown with small amounts of normal wood. On a whole tree basis the relationship was not as clear. In this case growth strain values determined from multiple measurements appear to be influenced primarily by tissue close to the site of measurements and not by wood at relatively remote locations. In some cases low growth strain values were found in trees with significant tension wood and in others high growth strain values where little tension wood had developed.

Nondestructive impact-induced resonance vibrations and spectral analysis were used to determine the dynamic modulus of elasticity (MOE) of specimens from 45 hardwood and 10 softwood species. Relationships were obtained between air-dry specimens measuring 20×20×300 mm and small wood beams measuring 20×2×150 mm (nominal) cut from them. Dynamic longitudinal elastic modulus (EL) and wave velocity (VL) in the fiber direction were determined from the larger specimens. These were compared with the dynamic flexural elastic modulus (ECB-cantilever mode) and the dynamic longitudinal elastic modulus (ELB) with the corresponding wave velocity (VBL) measured from the small beams. ECB and ELB were highly related to EL. VLB was similarly related to VL. The methods developed for small wood beams allow rapid evaluation of MOE from the outer wood of standing trees or they can be used for studies involving detailed localized evaluation of elastic wood properties.

Summary Static bending and dynamic resonance tests (flexure and longitudinal) were used to determine modulus of elasticity (MOE) of 167 wood specimens from clear and decayed regrowth Tasmanian oak (mostly Eucalyptus obliqua L'Herit.). Strong relationships were found between static and dynamic MOE for both the clear and decayed wood specimens. The type of wood (clear or decayed) did not affect the closeness of the relationships, nor did it cause noticeable differences between the regression equations.

Near infrared (NIR) spectroscopy was applied to fifty-four species (59 samples in total) representing a diverse array of taxonomic affiliations, wood chemistry and physical properties. Acetone and ethanol were used to remove extractives from the wood samples used in this study. The extracted samples were characterized in terms of collapse-free density, microfibril angle and longitudinal modulus of elasticity (estimated using the collapse-free density and X-ray diffraction data obtained from Silvi- Scan-2). NIR spectra were obtained from the radial longitudinal face of each sample and used to generate calibrations for the measured physical properties. Extraction was found to improve the calibration statistics for all properties.

Summary A new method developed at CSIRO allows longitudinal growth strain and dynamic Young's modulus in the fibre direction to be measured on the same specimen. From these two properties, longitudinal growth stress can be readily calculated by multiplying the two. In this study, growth strain, density and dynamic Young's modulus were measured on fifty-four specimens removed from 10-y-old plantation-grown trees of Eucalypts globulus Labill. The correlation between growth strain and density was found to be significant but weak (r 2 = 0.27, P < 0.05). There was no significant relationship between growth strain and Young's modulus. The large variation in growth strain (coefficient of variation = 62%) but a relatively small variation in Young's modulus (coefficient of variation = 18%) resulted in a strong linear correlation between growth strain and growth stress.

Wood stiffness varies enormously both within and between trees, so it is inevitable that low-grade solid wood products are produced from some trees. Accordingly, it would be highly desirable to segregate logs to ensure that only those logs with predominantly high stiffness wood are processed into structural lumber products. This study examined whether sound flight velocity (m s -1 ) could be used as a direct measure of wood stiffness to allow such segregation. Trees of radiata pine were measured before and after harvest with a non-destructive acoustic device (stress wave timer) to see if there was a relationship between sound wave velocity in either standing trees or logs and machine stress-grades of boards derived from those trees and logs. The speed of sound along logs was sufficiently closely correlated with wood stiffness to allow logs to be sorted into classes. A highly significant and positive relationship was found for acoustic measurements made in logs and a weaker, but still si- gnificant, relationship existed for acoustic measurements made in standing trees. Such segregation of logs according to wave velocity measured in the field may save a large sawmill between A$1-4m each year. Acoustic methods may also be used as an indirect tool for selection provided the heritability of the measurements is high enough and there is significant genetic correlation with genetic values for wood stiffness. From ano- ther experiment we have estimated the heritability of several acoustic measures and hope to be able to estimate genetic relationships with wood quality soon. modulus of elasticity / wood, acoustics / sound speed / selection

Summary Basic shrinkage properties of three provenances of 10-y-old plantation-grown Eucalyptus globulus Labill, from two sites in Mt Gambier region were determined. The properties included shrinkage and collapse in radial and tangential directions, and cross-sectional shrinkage after re-conditioning. Site had a highly significant effect on a number of shrinkage properties. There was no significant difference between provenances in any shrinkage property. Nevertheless, Jeeralang provenance consistently had the highest mean value for every shrinkage property in both radial and tangential directions (except for radial shrinkage), followed by King Island then South-eastern Tasmania provenances. Values for mean radial and tangential shrinkage, and mean radial collapse, in this study were well below the values of corresponding properties for 17–23-y-old E. globulus trees in Tasmania as reported by previous researchers. Internal checking was virtually absent in small specimens (20 mm × 20 mm × 90 mm) that were ...

), wave velocity (VL) in the fibre direction, dynamic flexural elastic modulus (EF), logarithmic decrement (LD) in air-dry specimens of Eucalyptus delegatensis R. Baker, measuring 20 × 20 mm transversely and 300 mm long. The dynamic properties were compared with the static elastic modulus (MOE) and the modulus of rupture (MOR) obtained from three point bending tests. EL was very highly related to EF, MOE, MOR and air-dry density, whereas the relationship between VL and static moduli was highly significant, but less strong. VL was related positively to air-dry density, and negatively to static shear modulus (Longitudinal-Tangential and Longitudinal-Radial planes). EF was the single best predictor of both MOE and MOR. LD was negatively related to MOE and MOR. The association between the dynamic (GF) and static (GST) shear modulus values was only moderately good. The mean dynamic modulus was 3.4 times greater than the mean static value. EL may be used to estimate the true Young's modulus in specimens in which shear contributes significantly to bending.

was studied using 12 mm increment cores taken from straight, vertical and dominant trees of three provenances from a plantation near Tarpina, South Australia. Tension wood fibre percentages were determined from microscopic examination of stained transverse sections and transverse shrinkage was measured from cores dried to 17% equilibrium moisture content. Shrinkage before and after steam reconditioning, as well as associated collapse, were related to the proportions of tension wood. Contrary to normal expectations, high levels of tension wood produced greater shrinkage in the sapwood than in the heartwood in material from all provenances. Collapse was significantly greater in material from the Jeeralang and Western Tasmania provenances than in the King Island provenance. While the mean proportion of tension wood was highest (4.3%) in material from Jeeralang and least from King Island (2.4%), no significant difference among the three provenances was evident for proportions of tension wood fibres when considering only the last year's growth. Variation in the width of the gelatinous layer (G-layer) was recorded for the tension wood fibres. Fibres with thin walled G-layers were usually scattered among normal fibres and collapsed regions containing such material generally recovered after reconditioning. On the other hand, regions containing the more typical tension wood fibres, with thick walled G-layers, exhibited high levels of shrinkage and collapse, and poor recovery after reconditioning.

Summary Density and microfibril angle (MFA) of tension wood and normal wood were assessed in the sapwood and heartwood, from three provenanaces of 10-year-old Eucalyptus globulus Labill. Density was measured using a modified saturation method that also enabled the calculation of the extractives lost during saturation. Microdensity and MFA were determined by SilviScan 2, a rapid X-ray densitometry and X-ray diffraction system developed at CSIRO. Significant differences were found in density and extractives between provenances and also density between the sapwood and adjacent heartwood from each provenance. This result may explain some of the drying differences between provenances found in an earlier study (Washusen and Ilic 2000). Sapwood samples with high percentages of tension wood fibres had high density and a significant positive correlation was found between microdensity and tension wood fibre percentage. MFA was found to be very low in normal wood in the sapwood, where most tension wood was found, so tension wood could not be identified by MFA. The positive association between tension wood and wood density suggests that caution should be taken when selecting trees for high wood density in tree improvement programs.