Maple Wood Research Articles

Nutrition and Related Factors Affecting Maple Tree Health and Sap Yield

The maple industry is an economically important bioresource for both Canada and the Northeastern United States, with Canada being the world leader in maple products. Maple sap is collected during the natural freeze-thaw cycles which occur in the late winter and early spring. Syrup yield is directly dependent on sap yield which has links to tree health, available nutrients, forest health, environment, soil health, sap components, season length, as well as various other factors. Maple trees can tolerate a wide arrange of soils, but soils in the maple woods are often left alone due to the difficulty with addition and incorporation of the appropriate amendments. Most nutrients come from the nutrient cycling of decomposing litter and mycorrhizal associations. Nutrient deficiencies of K, P and Ca are all linked to maple decline and could be positively influenced by a fertilization program. However, improper nutrient applications could create even greater nutrient imbalances, thus leading to more dieback or decline. This review discusses current maple management practices with an emphasis on the role of soil nutrition on tree health and sap yield.

"THE SURFACE ENERGY OF COATING LAYERS USED FOR VIOLINS VARNISHING "

Numerous studies on new and historical violins have highlighted the importance of coatings for the acoustics of the musical instrument. The purpose of this paper is to present the results regarding the surface energy of resonant wood, spruce and maple in two states: lacquered and unvarnished. The method is based on static contact angle measurements of sessile drops. The obtained results highlight large differences in surface energy depending on the wood section (radial versus longitudinal), surface (lacquered versus unvarnished), wood species. Thus, although the surfaces are polar for both unpainted and lacquered samples, it can be seen that there is a tendency to increase the contact angle after applying the surface treatment (applying the varnish). In the case of spruce wood cut in the longitudinal direction, the contact angle increases by about 31% in the case of the lacquered surface. For maple wood, the increase is 10%. For radially cut spruce wood samples, it is observed that the contact angle is higher than 90°, the surface having a hydrophobic character, a characteristic that is not found in maple wood. The application of the varnish on the radial surface diminishes the hydrophobic characteristics of the spruce wood. In maple wood, the difference between the longitudinal and radial samples is very small (2%).

EVALUATION OF VISCOUS-ELASTIC PROPERTIES OF RESONANCE MAPLE WOOD

The paper presents the experimental investigations regarding the viscoelastic behaviour of maple wood used in the construction of stringed musical instruments. The studied samples were classified according to the anatomical structure of the wood in the four classes of anatomical quality used by the manufacturers of musical instruments. Based on the mechanical analysis in dynamic regime, the viscoelastic parameters were determined - the preservation module E', the loss modulus E' and the damping tan δ, in conditions of constant temperature, respectively variable temperature. It was found that the determined rheological quantities depend on the anatomical structure of the wood, the frequency of the excitation and the temperature.

Effects of helix angle and feed per knife on the surface quality of sugar maple and black spruce boards produced by planing

ABSTRACT A conventional straight knife cutterhead and three helical knife cutterheads were tested for planing sugar maple (Acer saccharum Marsh.) and black spruce (Picea mariana (Mill.) B.S.P.) woods. The effects of helix angle and feed per knife (FK) on roughness, tactical perception, and anatomical features of the planed surfaces were evaluated. Rk and Rpk parameters were found to be more descriptive in evaluating the roughness of these woods and proved to be good indicators of tactile perception. Roughness increased as the helix angle and feed per knife increased for both wood species. Sugar maple showed smoother surface than black spruce. Surfaces planed with helical knives showed a fuzzy texture resulting from cell-wall fibrillation. For sugar maple wood, the differences in roughness between straight and 40° helical knives were small. Therefore, the latter must be preferred for planing this species. Roughness of planed black spruce also increased as helix angle increased and in this case its effect depended on FK. The straight knife produced the lowest roughness, for all studied FKs. Planing with helical knives produced higher roughness as a result of cell-wall fibrillation. This defect was more pronounced than that of sugar maple, and by far more present with helical knives of 50° and 60°. Therefore, straight knives working at low FK (1.3 mm) should be preferred for planing black spruce wood when roughness is a critical concern. Possible benefits provided by rougher surfaces planed by helical knives are discussed.

Using deciduous branch wood and conifer spindle wood to manufacture panels with transverse structure

The increasing demand on the wood market makes it necessary to use all secondary resources, including the wood branches and spindles. The properties of deciduous branches and softwood spindles were evaluated in order to create wood panels, highlighting the transverse texture with high value added. The research analyzed the properties of the wood from deciduous (beech, maple) branches and from conifer (spruce, fir) spindles. The methodology of obtaining panels with transversal structure was also presented. The production of minor wood (branches or spindles) was 254 m3/ha/year in the case of beech (branches) and 109 m3/ha/year in the case of spruce (spindles). The proportion of compression wood for spruce had an average value of 40.6%. A similar value of tension wood for beech was obtained. The modulus of elasticity for pine spindle wood was 71.7% lower than the modulus of elasticity for bending strength in the trunk. The quality index was 36.7% lower in the case of spindles than in the case of pine trunk, and the value of the quality ratio in branch maple wood was 2.61% lower than in trunk wood. Thus, even if it is not the only efficient solution, wood in the minor portions can be used to make high value-added panels such as those that highlight the transverse structure.

STUDY ON THE DECAY EXTENT OF WOODEN COMPONENTS OF DANXIA TEMPLE ANCIENT BUILDING BY POLARIZED LIGHT, FLUORESCENCE AND X-RAY DIFFRACTION METHODS

In the present study, the decay extent of wooden components from the Halls of Pilu and Tianran ancestor of Danxia Temple ancient buildings was observed by polarized light, fluorescence, and XRD methods. The findings of the investigation can be summarized as follows. Sample No. 1 was identified as red birch wood (Betula albo-sinensis) and sample No. 2 was identified as maple wood (Pterocarya stenoptera). The brightness of crystalline cellulose birefringence in the cell walls of vessels, wood rays and wood fibres, both in decayed red birch wooden components (DRBWC) and in decayed maple wooden components (DMWC), was not obvious, indicating that the cellulose was seriously consumed by fungi. However, the brightness of green fluorescence in the cell walls of both DRBWC and DMWC was very evident, indicating that the lignin was mainly retained or was not consumed by fungi. XRD analysis indicated that wood decay fungi did not change the structure and crystal layer distance of the crystallization zone, but the diffraction intensity decreased to a certain extent. The crystallinity of cellulose was reduced by 11.16%, from 43.29% to 38.46%, in DRBWC and by 52.16%, from 40.68% to 19.46%, in DMWC, demonstrating a reduction in crystalline cellulose. The degradation of cellulose in wooden components will eventually lead to a reduction in their load-bearing capacity. According to the tendency of brown rot fungi of consuming mostly cellulose and hemicelluloses while avoiding lignin, we concluded that both DRBWC and DMWC were seriously degraded by brown rot fungi, in addition to the attack of termites. The low resistance of the two wooden components to fungal decay and termites is the main cause of their deterioration. The results on the extent of decay will provide scientific data for the future conservation and restoration of the Danxia Temple relics.

Violin Varnishes: Microstructure and Nanomechanical Analysis.

The aim of the current work is twofold: to demonstrate the application of in situ non-invasive imaging by portable atomic force microscopy (AFM) on the surfaces of a violin and to integrate compositional and mechanical analysis at the nano scale level on model samples of varnished wood. These samples were prepared according to traditional recipes by an Italian lute-maker family well practised in the art. Samples of oil and spirit-based varnishes on maple wood, naturally and accelerated light aged, were studied. AFM was used to measure the nanomechanical properties of the model samples and established that the spirit-based varnish was stiffer than the oil-based. Synchrotron radiation micro- Fourier Transform Infra-red analysis of the layer structure revealed that stiffer spirit-based varnish showed less penetration into the wood than the oil-based. Further PeakForce Quantitative Nanomechanical Mapping (QNM) demonstrated a difference in adhesion values between the oil- and spirit-based samples.

Adding Value to Maple (Acer pseudoplatanus) Wood Furniture Surfaces by Different Methods of Transposing Motifs from Textile Heritage

The present paper is part of an ongoing research project carried out to find methods to transpose traditional motifs from Romanian textile heritage to furniture ornamentation, as an additional method of preserving the motifs besides conventional conservation. Modern technology, such as Computer Numerical Control (CNC) routing or laser engraving can revive furniture ornamentation, eliminating manual labor and long execution time. Three methods were applied to transpose a bicolored motif from a traditional Romanian blouse from Transylvania onto the surface of maple wood furniture. The first method utilized was nitrogen laser engraving, in which ten power settings between 10 W and 150 W were applied and color measurements were carried out on the resulting engraved surfaces. Following the International Commission on Illumination (CIELab) system analysis, two laser power settings were selected to engrave the ornament on a maple wood surface for an accurate reproduction. The second method employed a staining solution applied on flat wood surface, followed by routing the model on a CNC machine and further coating with lacquer. The third method consisted of CNC routing the model on the wood surface, then coloring the engraved ornament followed by surface sanding to remove color from the flat wood surface and, finally, lacquering. The ornaments transposed onto maple wood surfaces were aesthetically assessed, the technologies were analyzed, and the details of the processed ornaments were highlighted by Stereo Microscope investigation. The conclusions showed that each method adds value to the wood surface by original ornamentation and can be applied as furniture decoration.

Thermal Modification of Spruce and Maple Wood for Special Wood Products.

This article presents a proposal of thermal modification of Norway spruce and sycamore maple for special wood products, mainly for musical instruments. Selected physical and acoustical characteristics (PACHs), including the density (ρ), dynamic modulus of elasticity along the wood grain (EL), specific modulus (Esp), speed of sound along the wood grain (cL), resonant frequency (fr) and acoustic constant (A), logarithmic decrement (ϑ), loss coefficient (η), acoustic conversion efficiency (ACE), sound quality factor (Q), and the timbre of sound, were evaluated. These two wood species were chosen regarding their use in the production or repair of musical instruments. For the thermal modification, a similar process to the ThermoWood process was chosen. Thermal modification was performed at the temperatures 135 °C, 160 °C and 185 °C. The resonant dynamic method was used to obtain the PACHs. Fast Fourier transform (FFT) was used to analyze the sound produced. The changes in the observed wood properties depended on the treatment temperature. Based on our results of all properties, the different temperature modified wood could find uses in the making of musical instruments or where the specific values of these wood characteristics are required. The mild thermal modification resulted in a decrease in mass, density, and increased speed of sound and dynamic modulus of elasticity at all temperatures of modification. The thermally modified wood showed higher sound radiation and lower loss coefficients than unmodified wood. The modification also influenced the timbre of sound of both wood species.

Development of a universal method for high yield of furfural and hydrogen from raw lignocellulosic biomass

In order to develop a universal method for the co-production of furfural and hydrogen from raw lignocellulosic biomass, three types of substrates (maple wood, wheat straw, and tall fescue) were investigated, integrating chemical and electrochemical technologies. The results show both furfural and pure hydrogen were produced from all the biomass substrates, and the substrate type, composition, concentration, and size all affected furfural and hydrogen production. The highest furfural production of 154 mg g−1 substrate was achieved from wheat straw. The highest conversion rate of 67% for the waste furfural residue was realized, and 335 ml pure hydrogen per gram of furfural residue with a Faradaic efficiency of 99.3% was obtained with a new electrolytic cell. A reaction mechanism for hydrogen evolution from furfural residue and a rule for co-production of furfural and hydrogen from raw biomass were proposed. The facts show that a promising universal method for the co-production of furfural and hydrogen from lignocellulosic biomass has been developed.

Changing the vibrational behavior of the wooden thin arched plates—The maestro violins experimental study case

From a constructive and functional point of view, the violin body is a structure with thin walls having the role of amplifying the musical sounds and consists of an arched top and back plates, the ribs and the linings with thicknesses about 100 times smaller than the overall dimensions of violin body. The present research proposes to investigate: (i) the modification of the vibrational properties of the wooden arched thin plates in different stages of violin construction: as individual plates in preparation stages, then assembled in the violin body, after the addition of the neck and finally, as finished product; (ii) the influence of the plate thickness change on their vibrational behavior. The following dynamic properties were studied: frequencies of twisting mode #1, bending mode #2, ring mode #5 in case of unattached plates, frequencies of cavity mode (A), corpus bending modes (CBR), main body resonance (B), dominant frequency (extracted using Fast Fourier analysis from the sound signal) and quality factor which corresponds to dominant frequency. The change in the dynamic behavior of the plates during the manufacture of violins was statistically investigated using Discriminant Function Analysis. The research results showed that the top (spruce wood) and back plates (maple wood) have a very different vibrational behavior from each other due to wood species features. Changing the thickness of the plates by ±0.6 mm compared to the reference thickness leads to changing the frequency response of the back plates (maple). The thinner the plates, the more obvious the difference between the top and the back plate is, in terms of the maximum frequency. The stiffening of the plates mainly affects the quality factor of the sound oscillation damping, and the addition of the neck reduces the quality factor. Dynamic rigidity and frequency in cavity mode react most quickly to changes in plate thickness.

Characteristics and formation of nitrogen-containing products from the pyrolysis of maple wood and maize straw

Biomass is widely used in residential and industrial sectors as a renewable and carbon-neutral energy source, however, NOx emissions caused by the heat treatment of biomass are of concern. The nitrogen element in biomass plays an important role in N-containing products generated from pyrolysis, while the migration behaviors of fuel-N are still unknown. Slow pyrolysis experiments of maple wood and maize straw were conducted at 350–650 °C in this study. The TG, XPS and GC/MS technologies were performed to investigate the nitrogen migration pathways during prolysis. Results demonstrated that the fuel-N in the two species mainly exists as protein-N, amide-N and inorganic-N functional groups. Char-N occupied the most of total fuel-N from 350 °C to 450 °C, while the yields of tar-N and NOx precursors-N (NH3-N and HCN-N) increased gradually with the rising temperatures. NH3 was found to be the main NOx precursor for the both species, accounting for 15.01–20.19 wt% and 3.18–5.91 wt% of fuel-N in maple wood and maize straw, respectively. More than 85% of NH3-N was produced between 350 °C and 450 °C, attributing to the conversion of fuel-N and tar-N in the devolatilization stage. Differently, around 50% of HCN-N yields were produced by the secondary decomposition of tar-N and char-N at higher temperatures (≥550 °C). Particularly, char-N showed a greater thermal stability in maize straw, while a much higher conversion ratio of NOx precursors-N was observed from maple wood pyrolysis than that of maize straw. These results could provide some guidances on the control of NOx emissions from biomass energy utilization.

Structural changes from vibration welding of maple and pine woods analyzed by solid-state NMR

Structural changes from vibration welding of maple and pine woods analyzed by solid-state NMR

Influence of UV Radiation on the Color Change of the Surface of Steamed Maple Wood with Saturated Water Steam.

The wood of maple (Acer Pseudopatanus L.) was steamed with a saturated steam-air mixture at a temperature of t = 95 °C or saturated steam at t = 115 °C and t = 135 °C, in order to give a pale pink-brown, pale brown, and brown-red color. Subsequently, samples of unsteamed and steamed maple wood were irradiated with a UV lamp in a Xenotest Q-SUN Xe-3-H after drying, in order to test the color stability of steamed maple wood. The color change of the wood surface was evaluated by means of measured values on the coordinates of the color space CIE L* a* b*. The results show that the surface of unsteamed maple wood changes color markedly under the influence of UV radiation than the surface of steamed maple wood. The greater the darkening and browning color of the maple wood by steaming, the smaller the changes in the values at the coordinates L*, a*, b* of the steamed maple wood caused by UV radiation. The positive effect of steaming on UV resistance is evidenced by the decrease in the overall color difference ∆E*. While the value of the total color diffusion of unsteamed maple wood induced by UV radiation is ∆E* = 18.5, for maple wood steamed with a saturated steam-air mixture at temperature t = 95 °C the ∆E* decreases to 12.6, for steamed maple wood with saturated water steam with temperature t = 115 °C the ∆E* decreases to 10.4, and for saturated water steam with temperature t = 135 °C the ∆E* decreases to 7.2. Differential ATR-FTIR spectra declare the effect of UV radiation on unsteamed and steamed maple wood and confirm the higher color stability of steamed maple wood.

Signature Modes of Old and New Violins with Symmetric Anatomical Wood Structure

The paper aims to investigate old and new violins from the perspective of the correlation between the anatomical structure of spruce and maple wood, and the dynamic response of violins. Thus, in the first stage, for each violin, the characteristics of the annual rings were measured on the entire width of the top plate, determining the degree of symmetry of the face with respect to the longitudinal axis of the violin body. Then, each violin was dynamically tested with the impact hammer, determining its own frequency spectrum, mainly the so-called “signature” mode and quality factors. The most important findings consist of identification of the first five modes for old violins, (known as provenance), current new violins, and violins whose origin is unknown, but which could correlate with anatomical, constructive and dynamic characteristics, in order to be able establish origins, and also the measurement of anatomical features of top and back plates in the violins’ construction.

An African violin – The feasibility of using indigenous wood from southern Africa as tonewood

The wood used to make musical instruments needs to have particular properties. Depending on its function, such as a soundboard for string instruments or the body of a wind instrument, different properties are desirable to obtain the best musical quality. Several different classification schemes exist that correlate physical and mechanical properties of wood to define desirable ranges for tonewoods, and to allow suitable wood species to be chosen. The physical and mechanical properties of various wood species indigenous to southern Africa were characterised and then assessed in terms of their suitability for violin construction using these classification schemes. The results of this analysis show that the most suitable of the wood species assessed are yellowwood and sapele. These were subsequently used by a professional luthier to build an ‘African’ violin. The sound quality of this instrument was determined subjectively through performances to an audience and more objectively via spectral analysis of audio recordings. This analysis shows clear differences in the relative magnitude of the harmonics between the violin made from indigenous wood and an instrument made with conventional wood species. Despite the differences, yellowwood and sapele were found to be suitable tonewoods, resulting in an instrument with a unique sound.Significance: Good quality violins are always made from spruce and maple wood, which have to be imported to South Africa – often at high cost. However, the growth conditions of most southern African wood species should make them suitable tonewoods. We showed that several species are suitable to be used as tonewoods and that the sound produced with such a violin is – although somewhat different – of high quality.

The Influence of Drying Temperature on Color Change of Hornbeam and Maple Wood Used as Surface and Inner Layers of Wood Composites

The thermal treatment of wood changes its structure due to the degradation of wood polymers (cellulose, hemicellulose and lignin), so the physical properties of wood are either improved or degraded. Color changes apply not only to natural wood, but also to such wood composites for which some amount of glue is used in their construction (e.g., plywood, blockboard or laminboard). This article is focused on the analysis of hornbeam and field maple wood color changes influenced by drying temperature. Two types of drying modes were used: hot-air mode where the temperature of the drying environment was 60 °C, and high-temperature mode with a drying temperature of 120 °C. The drying mode was divided into two phases depending on the moisture content of the wood. The compared woods had similar values of color coordinates at the beginning of drying. During hot-air drying, the largest changes in color coordinates occurred during the first 24 h. The total color difference between the color at the end and the beginning of drying was 7.3 for hornbeam and 11.1 for maple. The overall color difference between the compared woods was minimal. During high-temperature drying (120 °C), the color changes of the dried woods were more pronounced. In the case of maple wood, there was a very significant change in color and the value of ΔE* was twice as high as for hornbeam. The total color difference between the color at the end and at the beginning of drying was 8.7 for hornbeam and 18.9 for maple.

Non-Destructive Determination of the Elastic and Acoustic Properties of Resonant Wood Used in the Manufacture of Violins

The aim of the paper was to determine the acoustic characteristics (speed of sound propagation in wood) and elastic (modulus of elasticity) on the three directions of wood, using non-destructive methods. The samples studied were cubic in shape from spruce and maple wood species, resonant and common. To determine the Young’s modulus and shear modules as well as the Poisson’s ratios, the expression of the propagation of Lamb waves generated and received using US translators with Hertzian contact with fr = 100kHz was used. The experimental data obtained show that mainly the velocities in radial and tangential direction are about one third of the longitudinal velocity, with the radial velocity higher than the tangential one. The radial velocity can be up to almost 14% higher than the tangential velocity. The applicability of this study consists in establishing the acoustic quality of the resonant wood from the Romanian area, used in the manufacture of our violins from the country.

Colour Stabilisation of Surface of Four Thermally Modified Woods with Saturated Water Vapour by Finishes.

This paper deals with the influence of the type of transparent surface finish on the change of colour of the surfaces of native wood, and thermally treated wood, with saturated water vapour. In the experiment, alder, European beech, Paper birch, and Norway maple wood were thermally treated at a temperature of 135 °C under saturated water vapour for six hours. Three various types of surface finishes (acrylic-polyurethane, polyacrylic and aldehyde resin, and alkyd resin) were applied onto the wood surfaces. The colours of the surfaces in the system, CIE L*a*b* (lightness, coordinates a* and b*, chroma and hue angle), were measured during finishing and natural ageing behind glass windows in an interior, over a period of 60 days. The results show that the changes in the yellowness index, and the total colour differences after the application of individual surface finishes to wood species, changed because of sunlight exposure. Moreover, it is clear that different wood finishes behaved differently on all of the wood species. An analysis is presented in this paper.

Study of selected properties of red maple wood (Acer rubrum) from the experimental plot of the forest arboretum in Rogów

Study of selected properties of red maple wood (Acer rubrum) form the experimental plot of the forest arboretum in Rogów. As part of the work, investigation on the dendrometric, physical and mechanical properties of red maple trees and its wood from the Forest Experimental Plant in Rogów has been carried out. The obtained results of the research on the species experimentally introduced in Rogów were compared with the features of the Acer rubrum from the area of natural occurrence in North America. The results of the investigation showed that the trees from the Arboretum area have a lower height, a much smaller trunk diameter and their physical and mechanical properties are weaker than the maple wood grown in native conditions. Despite the above statements, the significant influence of the location of the wood in the trunk (distance to the core) on its density, acoustic properties and static modulus of elasticity, bending and compression strength along the fibers are noted.