Variation In Wood Properties Research Articles

Radial Variation and Early Prediction of Wood Properties in Pinus elliottii Engelm. Plantation

To explore the radial variation in wood properties of slash pine (Pinus elliottii Engelm.) during its growth process and to achieve the early prediction of these properties, our study was carried out in three slash pine harvest-age plantations in Ganzhou, Jian, and Jingdezhen, Jiangxi province of South China. Wood core samples were collected from 360 sample trees from the three plantations. SilviScan technology was utilized to acquire wood property parameters, such as tangential fiber widths (TFWs), radial fiber widths (RFWs), fiber wall thickness (FWT), fiber coarseness (FC), microfibril angle (MFA), modulus of elasticity (MOE), wood density (WD) and ring width (RD). Subsequent systematic analysis focused on the phenotypic and radial variation patterns of wood properties, aiming to establish a clear boundary between juvenile and mature wood. Based on determining the boundary between juvenile and mature wood, a regression equation was used to establish the relationship between the properties of juvenile wood and the ring ages. This relationship was then extended to the mature wood section to predict the properties of mature wood. Our results indicated significant differences in wood properties across different locations. The coefficients of variation for RD and MOE were higher than other properties, suggesting a significant potential for selective breeding. Distinct radial variation patterns in wood properties from the pith to the bark were observed. The boundary between juvenile and mature wood was reached at the age of 22. The prediction models developed for each wood property showed high accuracy, with determination coefficients exceeding 0.87. Additionally, the relative and standard errors between the measured and predicted values were kept below 10.15%, indicating robust predictability. Mature wood exhibited greater strength compared to juvenile wood. The approach of using juvenile wood properties to predict those of mature wood is validated. This method provides a feasible avenue for the early prediction of wood properties in slash pine.

Review of Manufacturing Processes and Vibro-Acoustic Assessments of Composite and Alternative Materials for Musical Instruments

The evolution of musical instrument manufacturing has prompted a quest for innovative materials beyond traditional wood. This review explores the utilization of composite materials, 3D-printed materials, and metamaterials as favorable alternatives. The investigation is driven by challenges such as the scarcity of high-quality tonewoods, variations in wood properties, and environmental concerns. Carbon fiber, graphite fiber, ceramic polymers, and nanocomposites present promising alternatives, offering advantages in durability, weight reduction, and customizable acoustics. The integration of 3D printing technology introduces a cutting-edge dimension, enabling intricate, precisely engineered components, optimizing instrument structure, and allowing unprecedented customization. Additionally, this article explores metamaterials, leveraging unique mechanical properties from structural design rather than constituent materials. Metamaterials offer unprecedented capabilities for tailoring instrument vibrational characteristics by providing unparalleled control over sound production. The review provides a thorough analysis, including manufacturing methods for composite materials, metamaterials, and 3D printing in musical instruments. Comprehensive examinations of vibrational and acoustical analyses related to composite materials, 3D-printed materials, and metamaterials, for the evaluation of musical instruments, are presented. This overview, supported by experimental and numerical simulation methods, offers valuable insights for the future development of musical instruments.

Lower wood stiffness in old-growth than in post-cut and post-fire stands indicates forest structure is a key driver of wood properties in black spruce

Forest fires and logging drive the structure of boreal forest landscapes. According to recent studies, stand origin is a key driver of the variation in wood properties in black spruce (Picea mariana (Mill.) BSP.), although the underlying mechanisms remain to be elucidated. By comparing post-cut, post-fire and old-growth forests, this study aimed to better distinguish the effects of stand structure from those of the seed or layer origin of the trees on wood properties. We conducted comparative analyses based on ecological characteristics of the sites and static bending tests of small, defect-free wood specimens. Black spruce stands with a regular structure established after logging or fire exhibited higher stiffness at a given cambial age than old-growth forests with irregular structures, as well as lower wood density in the first 40 rings near the pith. However, the bending strength was comparable in all three types of forests studied. Differences in wood stiffness among stand types appeared to be driven more by stand structure than by the seed or layer origin of the stems.

Models to predict the radial variation of stiffness, strength, and density in planted noble fir, Norway spruce, western hemlock, and western red cedar in Great Britain

Key messageThis study compares the measured radial variation in wood stiffness, strength, and density of noble fir, Norway spruce, western hemlock, and western red cedar by developing mixed-effects models for each property using age as the explanatory variable. These models could be used to simulate the effect of rotation length and species choice on sawn wood properties.ContextTimber production in Great Britain relies primarily on Sitka spruce. The use of multiple species is desirable to mitigate against biotic and abiotic risks posed to a single species. When considering alternative species, quantifying and modeling radial variation in wood properties is important to determine the potential for sawn timber production at a given rotation length.AimsTo build empirical models for the radial variation in wood properties that can account for species.MethodsClear-wood samples were produced along radial transects in trees from four conifer species: Abies procera Rehder, Picea abies (L.) Karst, Tsuga heterophylla (Raf.) Sarg., Thuja plicata Donn. ex D.Don. Modulus of Elasticity, Modulus of Rupture, and density were measured on each species according to established standards. Mixed-effects models were built using ring numbers from the pith and species as explanatory variables.ResultsThe same model forms could be used across the four species. Nonlinear models were developed for the Modulus of Elasticity and density. For the Modulus of Rupture, a linear model was most appropriate. The effect of species in the models was significant.ConclusionAt similar rotation lengths, noble fir, Norway spruce, and western hemlock can produce timber with comparable properties to Sitka spruce. Overall, western red cedar would have worse properties for structural use.

Structural differences of cell walls in earlywood and latewood of Pinus sylvestris and their contribution to biomass recalcitrance.

Scots pine (Pinus sylvestris L.) is an evergreen coniferous tree with wide distribution and good growth performance in a range of habitats. Therefore, wood from P. sylvestris is produced in many managed forests and is frequently used in industry. Despite the importance of pine wood, we still do not fully understand its molecular structure what limits improvements in its processing. One of the basic features leading to variation in wood properties is the presence of earlywood and latewood which form annual growth rings. Here, we characterise biochemical traits that differentiate cell walls of earlywood and latewood in Scots pine. We discover that latewood is less recalcitrant to enzymatic digestion, with galactoglucomannan showing particularly pronounced difference in accessibility. Interestingly, characterisation of lignin reveals a higher proportion of coniferaldehydes in pine latewood and suggests the presence of a different linkage landscape in this wood type. With complementary analysis of wood polysaccharides this enabled us to propose the first detailed molecular model of earlywood and latewood and to conclude that the variation in lignin structure is likely the main determinant of differences in recalcitrance observed between the two wood types in pine. Our discoveries lay the foundation for improvements in industrial processes that use pine wood since we show clear pathways for increasing the efficiency of enzymatic processing of this renewable material. Our work will help guide future breeding of pine trees with desired timber properties and can help link molecular structure of softwood cell walls to function of the different types of xylem in conifers.

Shoot Phenology as a Driver or Modulator of Stem Diameter Growth and Wood Properties, with Special Reference to Pinus radiata

Seasonal phenology is expressed in the annual rhythms of growth and quiescence, which may range from being sharply defined to weakly quantitative. These rhythms, both vegetative and reproductive, are a key aspect of a plant’s survival strategy. They enable the plant to both survive seasonal stresses and take advantage of favourable conditions, while making pollination efficient through synchronised flowering. Maturation in woody perennials causes some ontogenetic modulation of seasonal phenology. Shoot phenology is driven by various environmental cues, notably temperatures and daylength, with shoot extremities often being prime receptors. The phenology of shoot extremities is in turn seen as a strong driver of cambial activity, which itself is an aspect of shoot phenology and the basis of stem diameter growth. The aspects of cambial activity reflecting hoot–tip phenology primarily involve the timing of xylem formation and the anatomical and physical properties of xylem cells. The actual amount of diameter growth, however, is governed much more by other factors, notably the growth potential of the species, the space for the tree to grow in, and how favourable local conditions are for growth. Somehow, all tree species allocate resources to shoot extension and diameter growth to represent viable adaptive strategies, although there is no identified role of phenology per se in such allocation. Among species, Pinus radiata is extremely important commercially, largely through a high growth potential that reflects distinctive phenology. Much research on the species provides a basis for linking its phenology and shoot–tip architecture to seasonal timing of diameter growth and fine details of within-ring variation in xylem cell properties. This provides a baseline for comparison with many other tree species, conifers and hardwoods. Selected examples are considered to illustrate the range of adaptive strategies. Regulation of diameter growth and internal variation in wood properties reflects the response to competitive pressures. Modifying the regulation to optimise wood production and quality poses a great challenge for future domestication.

Effect of tree wood density on energy release and charcoal reflectance under constant heat exposure

Background Charcoal increases in reflectance with increased intensity and/or duration of heating, and this has been proposed as a potential quantitative metric for fire severity. Because fuel properties also influence reflectance, relationships between heat exposure and reflectance must currently be considered fuel-specific, limiting the application of the method. Aims We assessed the effect of wood density on charcoal reflectance, to test whether it could be used as a proxy for overall variation in wood properties. Methods Wood samples from 25 tree species were charred under constant conditions in a microcalorimeter, and reflectance measured by microphotometry. Key results A positive linear relationship was found between wood density and charcoal reflectance (r = 0.53). Wood density was highly correlated with total heat release per unit volume (r = 0.94). Conclusions Wood density accounts for a substantial component of the variation in charcoal reflectance under constant heat exposure. Implications The relationship of density to reflectance shown here is relevant to the assessment of charcoals formed anaerobically, where endogenous heating (combustion of the sample itself) does not occur. In fire-produced chars, an additional increase in reflectance from endogenous heating should produce a stronger correlation, and density might account for a large component of the variation in reflectance under such conditions.

Using ensemble learning to model climate associated variation in wood properties of planted Eucalyptus nitens in north-western Tasmania

Using ensemble learning to model climate associated variation in wood properties of planted Eucalyptus nitens in north-western Tasmania

Relationship between the xylem maturation process based on radial variations in wood properties and radial growth increments of stems in a fast-growing tree species, Liriodendron tulipifera

Promoting wood utilization from fast-growing tree species is one solution to address supply and demand issues relating to wood resources while sequestering carbon dioxide in large quantities. Information on the quality of wood from fast-growing tree species and its relationship with changes in stem size is essential for promoting the establishment of plantations and wood utilization of fast-growing tree species. To explore the relationship between the xylem maturation process and radial growth increments of stems in fast-growing tree species, we examined radial variations in annual ring widths and wood properties in Liriodendron tulipifera in Japan. The cambial ages at which current annual increment and mean annual increment values were greatest were 4.9 years and 7.4 years, respectively. Based on radial variations evaluated by mixed-effects modeling of wood properties, all properties increased or decreased near the pith before becoming stable towards the cambium. Changing ratios of multiple wood properties at 1-year intervals became stable after a cambial age of 9 years. These results point to an ecological strategy in L. tulipifera, in which there is a tradeoff between radial growth increments and wood properties. As part of this strategy, in response to competition among individual trees within a stand, the tree produces a large volume of xylem with lower physical and mechanical properties, allowing it to increase its volume faster than that of the surrounding trees. Subsequently, it produces xylem that is more stable, with greater physical and mechanical properties. This wood forms at a slower growth rate compared to the xylem that forms at the time of initial tree growth. Based on the ecological strategy adopted by L. tulipifera, wood that forms before a cambial age of 9 years can be used for utility applications, and wood that forms after a cambial age of 9 years can be used for structural applications.

A Comparison of Radial Wood Property Variation on Pinus radiata between an IML PD-400 ‘Resi’ Instrument and Increment Cores Analysed by SilviScan

Mature age Pinus radiata D. Don trees were sampled across nine sites in northern New South Wales, Australia, that were expected, based on site quality and inventory metrics, to exhibit significant variation in productivity and wood quality. Twenty trees per site were harvested and 13 mm diameter, pith-to-bark increment cores were extracted from three trees per site from eight of the nine sites for SilviScan analysis. Outerwood increment cores were collected from all trees for basic density measurement. The same trees were also sampled using an IML PD400 (Resi) instrument. Radial mean properties of wood basic density derived from Resi traces were found to correlate strongly with the mean density data derived from SilviScan analyses and from increment cores. The Resi-derived basic density of 10 mm radial segments was strongly correlated with SilviScan measures of basic density averaged at similar intervals.

Evaluation of the age dependent variation of wood properties based on the eigenvalue distribution of near infrared spectral matrices

The age-dependent variation in wood properties is a very complex phenomenon because its pattern is highly dependent on tree species and wood traits. In this study, we evaluated the variation of multiple traits inclusively based on the distribution of eigenvalues calculated from the near-infrared spectral matrix at each cambial age. The experiments were conducted on four tree species with characteristic xylem structures, aiming to clarify the intrinsic behaviour of tree aging independent of tree species. The eigenvalues diffused with age in any species, such as in Dyson's Brownian motion. The gradual increase in the first eigenvalue, which is equivalent to the Helmholtz free energy, indicates that trees form a more ordered wood with age. As all the variations induced by various wood properties during the process of tree growth were aggregated into the set of eigenvalues, the Fokker-Planck equation representing the variation of eigenvalue distribution might provide a conclusive answer for the determination of demarcation between juvenile and mature wood. The age dependency of Shannon entropy and density matrix calculated from the probability associated with each energy eigenstate provided us with knowledge from the perspective of randomness; namely, tree aging from the perspective of the variation of wood properties was clearly an irreversible process. This result offers an important clue for sustainable forest management and the use of wood resources. The proposed method does not depend on a specific coordinate, thus, it will work well using data other than the near infrared spectrum.

Genetic variation in wood properties of mid-rotation age Eucalyptus globoidea

Background: Eucalyptus globoidea Blakely produces ground-durable (Class 2) and stiff wood and has the potential to be grown in New Zealand to supply high-value environmentally-friendly timber for use as posts in the agricultural sector and stiff veneers for the LVL industry. The New Zealand Dryland Forests Initiative (NZDFI) has established a breeding programme for this species. The objective of this study was to identify trees with superior wood properties for commercial propagation enabling the establishment of a domestic plantation resource of ground-durable timber. Methods: The genetic variation in wood properties at mid-rotation age (8-year-old) of 141 E. globoidea families was assessed for the following traits: heartwood diameter, diameter under bark at ~0.5 m height, combined sapwood diameter, heartwood collapse, sapwood collapse, standing tree acoustic velocity and extractive content in the heartwood. Families were ranked and genotypes with large heartwood diameter, high extractive content and stiffness as well as low collapse were identified. Results: Heartwood diameter (h2 = 0.51) and extractive content (h2 = 1.16) showed good heritability, which in combination with high variation are promising traits for a breeding programme. The high heritability for extractive content indicated a closer relatedness within the population than the assumption of unrelated families of half-siblings. The unfavourable correlation between the heartwood diameter and extractive content (genetic correlation (rg) = −0.45) indicated that a compromise is required for simultaneous improvement of both traits. Heritability estimates for heartwood collapse (h2 = 0.30) and acoustic velocity (h2 = 0.36) were moderate. Conclusions: Genetic selection for wood quality traits of E. globoidea is practically feasible. Superior individuals with above average performance for multiple traits were present in the breeding populations, however, this was dependent on the intended end use of the timber.

Variation in wood properties of 26-year-old Handroantus impetiginosus cultivated in Luiz Antônio, SP

Provenance testing can provide information on silvicultural behavior and wood quality of species for selection of genetic material for different locations and conservation of the genetic base. The aim of this work was to study the longitudinal variation of basic density, volumetric shrinkage and microfibril angle of wood from two provenances (Assis and Bauru) of Handroantus impetiginosus planted in Luiz Antonio SP. After 26 years of planting, twelve trees were felled, six from each provenance. According to the results obtained, it could be concluded that the analysis of variance (ANOVA) showed that for the provenance there was a significant variation for the volumetric shrinkage of the wood and for basic wood density and microfibril angle the significance of variation did not occur. The basic wood density varied significantly between the different positions, at the height of the tree and for volumetric shrinkage, and for the microfibril angle it did not occur. There is a positive relationship between tree height and basic wood density of wood, for Assis and Bauru provenances.

Determination of Geographical Origin and Tree Species Using Vis-NIR and Chemometric Methods

Abstract The variation of wood properties between different geographical origin and tree species has an important influence on end use applications. This study aimed to investigate the feasibility of wood origin and species classification based on visible and near infrared spectroscopy and chemometric methods. The influence of geographical origin on tree species identification also was analyzed. A total of 530 samples with 2 origins and 5 tree species were collected for analysis. The raw reflectance spectra were preprocessed by spectral transformation technique, and nonlinear discrimination models were built by support vector machine (SVM) using various spectral forms. Three algorithms—grid search (GS), genetic algorithm (GA), and particle swarm optimization (PSO)—were applied to optimize the parameters of SVM models, respectively. Regardless of spectral forms and optimization techniques, the prediction accuracy was lower than that of the calibration set for wood origin and tree species identification. Except for reflectance spectra, prediction accuracy of 100 percent was obtained based on SVM in combination with three algorithms for origin discrimination. However, SVM in combination with reflectance spectra and GS technique achieved the best prediction accuracy (93.18%) for tree species identification. These results demonstrated that visible and near infrared spectroscopy combined with chemometric techniques can be used for geographical origin and tree species determination.

Modeling of radial variations in wood properties and comparison of juvenile and mature wood of four common conifers in Mongolia

Abstract Pinus sylvestris L., Pinus sibirica Du Tour, Picea obovata Ledeb., and Larix sibirica Ledeb. are important forest tree species in Mongolia. The radial variations of wood anatomical characteristics, physical and mechanical properties were evaluated by linear or nonlinear mixed-effects models for effective wood utilization of those of conifers. Many of these wood properties either increased or decreased from the pith to the bark and then became nearly constant based on the selected models. The properties of mature wood were estimated by nonlinear mixed-effects models, suggesting that P. sylvestris and L. sibirica are suitable as structural lumber, P. sibirica can be used for furniture and other interior products, and P. obovata is suitable for structural lumber as well as for furniture or interior products.

Modeling of radial variations of wood properties in naturally regenerated trees of Betula platyphylla grown in Selenge, Mongolia

Wood properties, such as annual ring width, wood fiber length, vessel element length, basic density, air-dry density, dynamic Young’s modulus, modulus of elasticity (MOE), modulus of rupture (MOR), absorbed energy in impact bending, compressive strength parallel to grain, and shearing strength, were investigated for wood from 10 naturally regenerated trees of Betula platyphylla Sukaczev in Mandal, Selenge, Mongolia. Mixed-effects models were used to evaluate the radial variations in the wood properties. The mean values of wood properties obtained in the present study were in almost the same range, with a few exceptions, as those reported by other researchers for other Betula species. The radial variations of wood properties in B. platyphylla were well-fitted to a nonlinear mixed-effects model (logarithmic formula); all examined wood properties increased from the pith and then became constant toward the bark side. The wood properties significantly differed between the core and outer wood. Basic density, air-dry density, and dynamic Young’s modulus were significantly correlated with MOE, MOR, and compressive strength. It is concluded that when the wood of B. platyphylla is utilized as raw materials for solid wood products, the differences between the core wood and outer wood should be considered. In addition, the selection of wood with higher strength properties can be achieved using the wood density and dynamic Young’s modulus as indicators.

CHARACTERIZATION OF PAULOWNIA TOMENTOSA STEUD TREES GROWN IN A 5-YEAR-OLD PLANTATION IN COSTA RICA

Paulownia tomentosa is utilized in Costa Rica and other countries for wood production and as feedstock for biomass, though the variation of wood properties for this species is scarcely known. In this work, the specific wood properties of a 5-year-old plantation in Costa Rica were studied. The results showed that bark and pith percentage and wood specific gravity (SG) increased with tree trunk height, while the proportion of heartwood, green wood density and green wood moisture content decreased. The average wood SG was 0.26 and tended to increase from pith to bark. Low wood SG values are related to low mechanical properties, with the advantage that wood shrinkage is low as well, which gives this wood species the potential to be utilized for reforestation purposes in Costa Rica. The gross calorific value of this species was 17809 kJ/kg, which, together with its cellulose and extractives contents, recommend P. tomentosa as a biomass source for energy production.

Mechanical properties of secondary quality beech (Fagus sylvatica L.) and oak (Quercus petraea (Matt.) Liebl.) obtained from thinning, and their relationship to structural parameters

• Key message This paper investigates the juvenility limit and structure–property relationship in secondary quality beech ( Fagus sylvatica L.) and oak ( Quercus petraea (Matt.) Liebl.). The juvenile wood occupies a very small area near the pith. The stabilization of the different parameters varies over time. Adding the microfibril angle (MFA) and the grain angle to the MOE prediction model significantly improves the quality of the model, despite little variation in both parameters. • Context Using secondary qualities and small logs of hardwoods such as beech and oak for engineered wood products is an increasingly important issue due to the technological challenges of processing smaller logs and denser woods. Secondary quality hardwoods are expected to have less variation in mechanical properties compared to softwoods with high juvenile wood content. • Aims The first objective of this study was to investigate the radial variation in wood properties of suppressed growth beech and oak trees obtained from thinning operations. The second objective was to develop a model to predict the mechanical properties of these hardwood species based on their structural parameters. • Methods The microfibril angle, ring wood density, and ring width from the pith to the bark were determined using an X-ray densitometer. The modulus of elasticity and modulus of rupture were evaluated on the small clear specimen using a three-point bending test. The wood density, grain angle, and microfibril angle of this small clear specimen were also measured. • Results The results show that the juvenile wood in oak has a wider ring and higher microfibril angle, whereas it has wider latewood and higher microfibril angle in beech. For both species, the juvenile wood occupies a very small area, less than 5 cm from the pith. The mechanical properties of oak and beech wood from suppressed growth trees are comparable to properties reported in the literature for dominant trees. The modulus of elasticity of oak was best predicted using wood density, grain angle, and microfibril angle. The modulus of rupture of oak is better predicted with wood density and grain angle, whereas it is best predicted with wood density alone for beech. • Conclusion Juvenile wood found in the suppressed growth trees of both hardwoods can be used in place of mature wood. It is important to take structural parameters into account when predicting the mechanical properties of hardwood species.

Variation in Wood Properties of Hybrid Poplar Lumber by Radial and Vertical Position in Stem: A Case Study from Boardman, Oregon

Understanding of wood quality of hybrid poplar is critically important for manufacturers who want to know the suitability of the wood for specific products. To this end, lumber was milled from the merchantable stem of four hybrid poplar clones ages 10-11 yr., grown at single site near Boardman, OR. The vertical and radial position in the stem were recorded for each board and the boards were kiln dried, surfaced, and samples from each board tested to determine specific gravity (SG), dimensional stability, hardness, screw withdrawal, and bending strength and stiffness (modulus of rupture [MOR] and modulus of elasticity [MOE], respectively) from small clear specimens. Results show differences in wood properties relative to vertical and radial position in the stem. SG, hardness, screw withdrawal, and bending properties of lumber samples generally increased with height in tree. Tangential hardness, SG, and MOR varied significantly between different sides of the trees corresponding to predominant wind in the area. Boards milled from the center of the stem had lower MOE and MOR than boards milled from nearer the bark. The results of this study may be used to target specific stem locations for different end uses.

Genetic Evaluation and Combined Selection for the Simultaneous Improvement of Growth and Wood Properties in Catalpa bungei Clones

Catalpa bungei is an important timber tree. Improvements in growth and wood quality are important goals of C. bungei breeding, and it is necessary to understand the genetic parameters of specific target traits and genetic correlation between growth traits and wood properties for tree breeding. In this study, the genetic parameters of height, diameter at breast height (DBH) and wood properties were estimated and genetic and phenotypic correlations between growth traits and wood properties were evaluated in C. bungei. Finally, different selection scenarios were used to evaluate and select optimal clones. The results showed that there were significant differences in growth and wood properties among clones. The wood hardness (0.66–0.79), basic density (0.89), air-dried density (0.89) and compression strength parallel to the grain of wood (CSP) (0.84) had high repeatability. The variance component proportions indicated that the variation in wood properties came mainly from different genotypes (clones) rather than from different individuals of the same clone. The DBH showed a significant negative genetic correlation with the hardness of radial section (HRS) (−643), basic density (−0.531) and air-dry density (−0.495). This unfavorable relationship makes it difficult to improve growth and wood quality simultaneously in C. bungei. We selected the optimal clones under different scenarios, and we obtained 7.75–9.06% genetic gains for growth in the scenario in which height and DBH were the target traits. Genetic gains of 7.43–14.94% were obtained for wood properties by selecting optimal clones in the scenario in which wood properties were the target traits. Approximately 5% and 4% genetic gains were obtained for growth and wood properties, respectively, for the combined selection. This study provides new insights into the genetic improvement of wood quality in C. bungei.