Evaluating growth strain of Eucalyptus globulus Labill. from SilviScan measurements

Holzforschung ◽  
2006 ◽  
Vol 60 (5) ◽  
pp. 574-579 ◽  
Author(s):  
Jun Li Yang ◽  
Henri Baillères ◽  
Robert Evans ◽  
Geoff Downes
Keyword(s):  
Eucalyptus Globulus ◽  
High Spatial Resolution ◽  
Microfibril Angle ◽  
Wood Property ◽  
Wood Properties ◽  
Surface Strain ◽  
Longitudinal Displacement ◽  
Cellulose Crystallite ◽  
Measured Strain

Abstract Longitudinal surface strain was measured or estimated using three different methods along the stems of nine trees of 10-year-old Eucalyptus globulus Labill. Wood samples were collected close to the location where the strain was measured or estimated. Microfibril angle (MFA), cellulose crystallite width (Wcryst), microdensity and Young's modulus along the grain (EL) were determined using the SilviScan-2 technology at high spatial resolution. Relationships of measured strain and estimated strain to wood properties were established. The quality of the relationships depends on a particular wood property. Strain was more closely related to mean Wcryst than to any other wood properties. Its relationship with MFA was the next closest. Based on the results of regression analysis, we propose that Wcryst may be suitable for the prediction of surface strain at a moderate level of reliability. Adding measurement of MFA, microdensity and EL does not significantly improve the prediction quality. The strain measurement method also affects the results. The best relationships were obtained with longitudinal displacement measured by the CIRAD method. Strain measured by the strain gauge method gave weak relationships, possibly owing to variation in the cambium age of the specimens.

scholarly journals High Resolution Scanning of Radial Strips cut from Increment Cores by Near Infrared Spectroscopy

IAWA Journal ◽  
2007 ◽  
Vol 28 (4) ◽  
pp. 473-484 ◽  
Author(s):  
P. David Jenes ◽  
Laurence R. Schimleck ◽  
Chi-Leung So ◽  
Alexander Clark III ◽  
Richard F. Daniels
Keyword(s):  
Infrared Spectroscopy ◽  
High Resolution ◽  
Spatial Resolution ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
High Spatial Resolution ◽  
Microfibril Angle ◽  
Wood Property ◽  
Nir Spectroscopy ◽  
Wood Properties

Near infrared (NIR) spectroscopy provides a rapid method for the determination ofwood properties of radial strips. The spatial resolution of the NIR measurements has generally been limited to sections 10mm wide and as a consequence the estimation of wood properties of individual rings or within rings has not been possible. Many different NIR instruments can be used to collect NIR spectra from the surface of radial strips at relatively high spatial resolution and the purpose of this study was to compare wood property calibrations obtained using NIR spectra collected in 5 mm and 2 mm seetions with several different NIR instruments. We found that calibrations based on spectra collected in 5 mm seetions had good statistics, with those based on the Bruker Vector 22/N spectrometer the strongest. Of the three properties examined (density, microfibril angle and stiffness), density had the weakest statistics. When the spatial resolution was decreased to 2 mm, calibration and prediction statistics were weaker than those at 5 mm. RPDp's were relatively low with the highest being 1.76 for predicted stiffness based on NIR spectra obtained using the ASD Field Spec Pro spectrometer. Based on the low RPDp's, we conclude that none of the instruments examined were suitable for scanning radial strips at a spatial resolution of 2 mm.

Direct Effects of Wood Characteristics on Pulp and Handsheet Properties of Eucalyptus globulus

Holzforschung ◽  
2002 ◽  
Vol 56 (3) ◽  
pp. 244-252 ◽  
Author(s):  
R. Wimmer ◽  
G.M. Downes ◽  
R. Evans ◽  
G. Rasmussen ◽  
J. French
Keyword(s):  
Wood Density ◽  
Eucalyptus Globulus ◽  
Strong Predictor ◽  
Fibre Length ◽  
Microfibril Angle ◽  
Wood Properties ◽  
Bending Stiffness ◽  
Pulp Yield ◽  
Paper Properties ◽  
Handsheet Properties

Summary Fibre length, microfibril angle and wood density were measured in eight-year-old Eucalyptus globulus clones planted on three different sites. Samples were chipped and pulped, and the pulps beaten prior to preparation of 60g/m2 handsheets. Eleven physical handsheet properties, together with pulp freeness, were measured using standard methods. Direct relationships between wood properties and pulp/paper properties were studied using path analysis. Fibre length had a strong, direct effect on tear index, bending stiffness, freeness, pulp yield and active alkali consumption. Wood density was a strong predictor of most handsheet properties: high density woods produced bulkier, more porous sheets with higher bending stiffness, while lower density woods produced smoother, denser sheets with higher tensile strength.The effect of microfibril angle was small and more evident in handsheets made from beaten pulp.

scholarly journals Classifying Wood Properties of Loblolly Pine Grown in Southern Brazil Using NIR-Hyperspectral Imaging

Forests ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 686
Author(s):  
Laurence Schimleck ◽  
Jorge L. M. Matos ◽  
Antonio Higa ◽  
Rosilani Trianoski ◽  
José G. Prata ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Hyperspectral Imaging ◽  
Loblolly Pine ◽  
Microfibril Angle ◽  
Wood Property ◽  
Wood Properties ◽  
Dry Density ◽  
Timber Species ◽  
Southern Brazil ◽  
Improvement Programs

Loblolly pine (Pinus taeda L.) is one of the most important commercial timber species in the world. While the species is native to the southeastern United States of America (USA), it has been widely planted in southern Brazil, where it is the most commonly planted exotic species. Interest exists in utilizing nondestructive testing methods for wood property assessment to aid in improving the wood quality of Brazilian grown loblolly pine. We used near-infrared hyperspectral imaging (NIR-HSI) on increment cores to provide data representative of the radial variation of families sampled from a 10-year-old progeny test located in Rio Negrinho municipality, Santa Catarina, Brazil. Hyperspectral images were averaged to provide an individual NIR spectrum per tree for cluster analysis (hierarchical complete linkage with square Euclidean distance) to identify trees with similar wood properties. Four clusters (0, 1, 2, 3) were identified, and based on SilviScan data for air-dry density, microfibril angle (MFA), and stiffness, clusters differed in average wood properties. Average ring data demonstrated that trees in Cluster 0 had the highest average ring densities, and those in Cluster 3 the lowest. Cluster 3 trees also had the lowest ring MFAs. NIR-HSI provides a rapid approach for collecting wood property data and, when coupled with cluster analysis, potentially, allows screening for desirable wood properties amongst families in tree improvement programs.

Temporal variation in δ13C, wood density and microfibril angle in variously irrigated Eucalyptus nitens

2009 ◽  
Vol 36 (1) ◽  
pp. 1 ◽  
Author(s):  
David M. Drew ◽  
E. Detlef Schulze ◽  
Geoffrey M. Downes
Keyword(s):  
Water Stress ◽  
Temporal Variation ◽  
Wood Density ◽  
Stable Carbon Isotope ◽  
Microfibril Angle ◽  
Wood Property ◽  
Wood Properties ◽  
Eucalyptus Nitens ◽  
Stable Carbon ◽  
Over Time

Wood can serve as a record of past climate, recording tree responses to changing conditions. It is also valuable in understanding tree responses to environment to optimise forest management. Stable carbon isotope ratios (δ13C), wood density and microfibril angle (MFA) are potentially useful wood property parameters for these purposes. The goal of this study was to understand how δ13C varied over time in response to cycles of soil drying and wetting and to variation in temperature in Eucalyptus nitens Deane & Maiden, in concert with wood density and MFA. δ13C increases did not necessarily occur when water stress was highest, but, rather, when it was relieved. Our hypothesis is that this was a result of the use of previously fixed carbohydrate reserves when growth and metabolic activity was resumed after a period of dormancy. MFA in particular showed concomitant temporal variation with δ13C. A peak in δ13C may not coincide temporally with an increase in water stress, but with a decrease, when higher growth rates enable the final incorporation of earlier stored photosynthate into mature wood. This has implications for using δ13C as a tool to understand past environmental conditions using radial measurements of wood properties. However, interpreting this data with other wood properties may be helpful for understanding past tree responses.

scholarly journals Genetic Variation of Physical and Chemical Wood Properties of Eucalyptus globulus

2005 ◽  
Vol 54 (1-6) ◽  
pp. 160-166 ◽  
Author(s):  
L. A. Apiolaza ◽  
C. A. Raymond ◽  
B. J. Yeo
Keyword(s):  
Genetic Variation ◽  
Eucalyptus Globulus ◽  
Genetic Correlations ◽  
Fibre Length ◽  
Microfibril Angle ◽  
Basic Density ◽  
Wood Properties ◽  
Pulp Yield ◽  
Cellulose Content ◽  
Wood Processing

Abstract This study considered the degree of genetic variation for diameter (DBH), basic density (BD), predicted pulp yield (PPY), fibre length (FL), microfibril angle (MFA) and cellulose content (CC) amongst eight subraces of Eucalyptus globulus growing in a field trial in NW Tasmania. There were significant subrace effects for BD, FL and CC. This variation affected the relative profitability of the subraces for pulp production. On average, the most profitable subraces (on NPV/ha over the base population mean) were Strzelecki Ranges ($862.04), Western Otways ($657.80) and Strzelecki Foothills ($576.81). The genetic control (heritability) of variation in DBH, FL and MFA was moderate (0.15 < h2< 0.27), while control for BD, PPY and CC was high (h2> 0.40). Genetic correlations between growth and wood properties were not statistically significant, except for DBHMFA (-0.86). Most genetic correlations amongst wood properties were outside the parametric space (< -1 or >1), but there were significant correlations between BDMFA (-0.70) and PPY-CC (0.82). The empirical response to selection on an index based on a pulp wood objective (which included volume and basic density) resulted in a gain of 4.3% for DBH, 7.9% for BD and marginal changes for all other traits, with a net impact in profit of $1,270/ha. However, future profit calculations will need to consider the effect of FL, MFA and CC on the economics of wood processing to fully evaluate the economic impact of breeding.

Characterization of the wood quality of pernambuco (Caesalpinia echinata Lam) by measurements of density, extractives content, microfibril angle, stiffness, color, and NIR spectroscopy

Holzforschung ◽  
2009 ◽  
Vol 63 (4) ◽  
Author(s):  
Laurence R. Schimleck ◽  
Charles Espey ◽  
Christian R. Mora ◽  
Robert Evans ◽  
Adam Taylor ◽  
...  
Keyword(s):  
Near Infrared ◽  
Wood Quality ◽  
Microfibril Angle ◽  
Wood Property ◽  
Nir Spectroscopy ◽  
Principal Component ◽  
Wood Properties ◽  
Average Density ◽  
Dry Density ◽  
Caesalpinia Echinata

Abstract A total of 30 Caesalpinia echinata (pernambuco) sticks were ranked based on their suitability for making high quality bows and were assigned to one of the three following categories: 0=very poor to poor, 1=good to very good, and 2=excellent. From the end of each stick a sample was cut for wood property and near infrared (NIR) spectroscopic analysis. Wood properties measured included air-dry density, extractives content, microfibril angle, stiffness and wood color. NIR spectra were evaluated by principal component analysis (PCA) and on the PC scores. Poor quality samples were discriminated from those of good to very good and excellent quality; however, samples from the two higher quality groups were mixed. Based on relationships observed between PC scores and wood properties, we suggest that, of the measured properties, density and stiffness were the most important in sample discrimination based on quality. Samples ranked in the excellent category had high average density (1119 kg m-3) and stiffness (25.2 GPa) and relatively low extractives content (21.2%) compared to samples in the very poor to poor category (density= 938 kg m-3, stiffness=18.9 GPa and extractives content=24.9%).

Radial variation in pernambuco (Caesalpinia echinata) wood properties

IAWA Journal ◽  
2017 ◽  
Vol 38 (1) ◽  
pp. 99-104
Author(s):  
Laurence R. Schimleck ◽  
Jorge Luis Monteiro de Matos ◽  
Charles Espey
Keyword(s):  
Management Practices ◽  
Wood Quality ◽  
Microfibril Angle ◽  
Wood Property ◽  
Wood Properties ◽  
Average Density ◽  
Radial Variation ◽  
Raw Material ◽  
Property Variation ◽  
Caesalpinia Echinata

Caesalpinia echinata Lam. (pernambuco or pau-brasil) is recognized as the premier raw material for manufacturing stringed instrument bows. Several studies have identified properties considered important in determining the suitability of pernambuco wood for bow manufacture including density, modulus of elasticity (MOE), and, possibly, microfibril angle (MFA). No research has been conducted on how these properties vary within individual trees; however, an understanding of how pernambuco wood properties vary within trees is important as it may assist in the identification of trees or provenances most suited for the establishment of plantations, aid in developing an understanding of management practices on wood property variation for plantation-grown pernambuco and also facilitate the identification of regions within trees that possess optimal properties for bow manufacture. Radial variation in density, MFA and MOE was examined using SilviScan for three radial strips representing differing levels of wood quality in terms of perceived suitability for making high-quality bows. The lowest quality sample showed considerable radial variation compared to the higher quality samples for all properties and it also had the lowest average density. It was not possible to identify a strong pith to bark trend for any of the wood properties examined.

Some Tree Growth – Wood Property Relationships of Eucalypts

1975 ◽  
Vol 5 (3) ◽  
pp. 424-432 ◽  
Author(s):  
J. E. Nicholson ◽  
W. E. Hillis ◽  
N. Ditchburne
Keyword(s):  
Wood Property ◽  
Basic Density ◽  
Wood Properties ◽  
Reaction Wood ◽  
Growth Strain ◽  
Fiber Structure ◽  
Tree Crown ◽  
Stem Form ◽  
The Relationship ◽  
Longitudinal Growth Strain

The relationship between level of longitudinal growth strain and stress, modulus of elasticity, basic density, volumetric shrinkage, fiber classification, and stem form was investigated with 10 Eucalyptusregnans regrowth trees. Close relationships were observed. It is suggested that variations in these properties within trees are closely controlled, possibly to enable optimum positioning of the tree crown in relation to its immediate environment. The concept of fiber structure varying as a response to environment is supported by the observed variation in wood properties within and between trees of this species. The often-reported association between eccentric radial growth and reaction wood was not substantiated in this study.The data indicate that if economically justifiable, it would be possible to segregate trees that are likely to contain material that is hard to season.

scholarly journals Development of Testing Platform and Comparison Studies for Wood Nondestructive Testing

2016 ◽  
Vol 2016 ◽  
pp. 1-7
Author(s):  
Jian Li ◽  
Yiming Fang ◽  
Jiyong Tang ◽  
Hailin Feng ◽  
Xiongwei Lou
Keyword(s):  
Nondestructive Testing ◽  
Stress Wave ◽  
Virtual Instrument ◽  
Wood Properties ◽  
Time Interval ◽  
Peak Time ◽  
Testing Platform ◽  
Time Interval Measurement ◽  
Nondestructive Testing Methods

Stress wave based techniques have been developed for evaluating the quality of the wooden materials nondestructively. However the existing techniques have some shortcomings due to the significant variation of the wood properties and are now in need of updating. There are also stress wave based instruments which have been widely used for nondestructive testing of wood. But most of them are inflexible and unsuitable for the tentative studies. This paper proposed and implemented a wood nondestructive testing platform based on NI virtual instrument. Three wood nondestructive testing methods, including peak time interval measurement, cross-correlation, and spectrum analysis, were also tested on this platform with serious decay sample, early decay sample, and defect-free sample. The results show that new methods can be verified easily and the researches of wood nondestructive testing will be accelerated with the designed platform.

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