Heartwood Content Research Articles

Structural development of redwood branches and its effects on wood growth

Redwood branches provide all the carbohydrates for the most carbon-heavy forests on Earth, and recent whole-tree measurements have quantified trunk growth rates associated with complete branch inventories. Providing all of a tree's photosynthetic capacity, branches represent an increasing proportion of total aboveground wood production as trees enlarge. To examine branch development and its effects on wood volume growth, we dissected 31 branches from eight Sequoia sempervirens (D. Don) Endl. and seven Sequoiadendron giganteum Lindl. trees. The cambium-area-to-leaf-area ratio was maintained with size and age but increased with light availability, whereas the heartwood-deposition-area-to-leaf-area ratio increased with size and age but was insensitive to light availability. The proportion of foliage mass arrayed in <1-cm-diameter epicormic shoots increased with decreasing light and was higher in Sequoia (20-60%) than in Sequoiadendron (3-16%). Well-illuminated branches concentrated leaves higher and distally, while shaded branches distributed leaves lower and proximally. In similar light environments, older branches distributed leaves lower and more proximally than younger branches. Branch size, light, species, heartwood area, a heartwood-area-species interaction, and ovulate cone mass predicted 87.5% of the variability in wood volume growth of branches. After accounting for the positive effects of size and light, wood volume growth declined with heartwood area and age. The effect of age was trivial compared to the effect of heartwood area, suggesting that heartwood expansion caused the age-related decline in wood volume growth. Additionally, Sequoiadendron branches of similar size and light environment with more ovulate cones produced less wood, even though these cones were long-lived and photosynthetic, reflecting the energetic cost of seed production. These results contributed to a conceptual model of branch development in which light availability, injury, heartwood content, gravity, and time interact to produce the high degree of branch structural variation evident within redwood crowns.

Heartwood, sapwood and bark content of teak trees grown in Karnataka, India

We evaluated heartwood, sapwood and bark content in teak trees. A total of 27 sample plots were laid out in teak plantations raised by State Forest Department in Karnataka covering different age groups (11–36 years), density (516–2061 trees/ha) and sites. From these plantations, a total of 130 trees were felled for estimating the yield and bark content in relation to diameter at breast height (DBH), age and density. Bark content ranged from 22.2%–54.3%. Heartwood and sapwood content were analyzed by sampling five trees each from two different plantations, one 30 years old at 553 trees·ha−1 and the other 32 years old at 911 trees·ha−1. The highest heartwood proportion of stem wood volume (over-bark) was 56.3% and the lowest was 37.1%. The sapwood proportion ranged from 12.9%–23.0%, while the bark content ranged from 27.8%–43.5%. The heartwood proportion increased with DBH, while the proportion of bark decreased. The sapwood proportion did not vary with DBH. The bark content decreased with increasing age, but increased with stand density. There was no significant difference in heartwood content with respect to age or stand density because the ages of the two stands were similar. A larger dataset from young to mature stands is needed to describe the relationships between age and stand density and heartwood, sapwood and bark content of trees.

Family effects in heartwood content of Eucalyptus globulus L.

Thirty families of Eucalyptus globulus L., established in a first-generation open-pollinated progeny test, were evaluated for the production of heartwood. Five trees of each family were harvested at 9 years of age, total tree height was measured and a cross-sectional disc was removed at 25 % stem height to estimate the amount of heartwood. The heartwood proportion of the stemwood cross-sectional area averaged 41 % with significant between-family variation (P = 0.016) ranging from 27 to 53 %. There were also important within-family differences with coefficients of variation of the mean between 4 and 48 %. Moderate heritability values were obtained for heartwood diameter and proportion (h 2 = 0.31 and 0.23, respectively) but low estimates were found for sapwood width (h 2 = 0.17). Strong positive genetic and phenotypic correlations of heartwood diameter were found with stem DBH and with heartwood proportion. Both correlation estimates indicated that larger trees tended to have more heartwood. The results indicate that there is an opportunity to reduce heartwood content in E. globulus through selection and breeding.

Heartwood stump colonisation by Heterobasidion parviporum and H. annosum s.s. in Norway spruce (Picea abies) stands

Stump-to-tree spread is a key step in the root and butt-rot disease caused by Heterobasidion annosum sensu lato. In Norway spruce stands, Heterobasidion parviporum is more likely to spread to neighbouring trees from stumps with a large diameter than from small stumps. However, H. annosum sensu stricto does not appear to share this pattern of infection. Given that the ratio of heartwood to sapwood varies depending on the size of the stump, we investigated the role of heartwood and sapwood in stump infection by H. parviporum and H. annosum s.s. To determine whether heartwood–sapwood susceptibility was different in different host species, both Norway spruce and Scots pine stumps were included in the study. Sapwood, heartwood and the border zone between sapwood and heartwood of spruce stumps and the heartwood and sapwood of pine stumps were artificially inoculated with different genotypes of H. annosum s.s. and H. parviporum. Only one zone was inoculated per stump. Infection was assessed 2 and 10months after inoculation at 5 and 30cm below the point of inoculation. On spruce stumps, H. parviporum and H. annosum s.s. were mostly confined to the heartwood. The area infected by H. annosum s.s. was smaller than that infected by H. parviporum. Both sapwood and border infections tended to grow towards the heartwood, whereas heartwood inoculations tended to remain in the heartwood, indicating that heartwood was more favourable for H. parviporum and H. annosum s.s. colonisation in spruce stumps. On pine, heartwood colonisation failed and only H. annosum s.s. was found in the sapwood. Our results suggest a possible association between the size of the stump and the spread of H. annosum s.s. to neighbouring trees mediated by the heartwood content, suggesting that screening for heartwood resistance could be a potentially interesting direction for future research. Treating stumps at final felling would be advisable owing to the large area of heartwood exposed by this operation.

Heartwood of Cupressus lusitanica, C. macrocarpa, Leyland and Ovens cypress and prediction of its durability using near-infrared spectroscopy

The heartwood of plantation-grown Cupressus lusitanica, C. macrocarpa, Leyland and Ovens cypress (×Cuprocyparis leylandii and ×C. ovensii) from trials in New Zealand, was evaluated using breast height increment cores and in vitro decay tests with fungal cultures to determine the variation in the heartwood content and natural durability, and its prediction using near-infrared (NIR) spectroscopy. The increment core measurements showed the length of the cores was strongly influenced by the stocking and site, but the heartwood content and weight loss with decay testing were strongly influenced by species and genotype. The heartwood content was consistently high for C. macrocarpa, but varied widely for C. lusitanica, and the Leyland and Ovens cypress clones. The weight loss was similar for the species and cypress clones, with the heartwood classified as very durable and durable, but there were differences in the distributions of less durable heartwood. The NIR calibration models of mass loss with fungal decay testing had ratios of prediction to deviation (RPD) of 1.0–1.3, which suggests the models could be used to segregate the heartwood for high and low values of natural durability.

Heartwood detection for Scotch pine by fluorescence image analysis

Abstract Heartwood detection for Scotch pine (Pinus sylvestris) is possible via several different methods, such as X-ray and infrared cameras. X-ray systems are often very expensive and need huge modifications of sawmill equipment for implementation. Infrared cameras are more affordable but can only be applied for fresh samples with high water content. This article describes a novel imaging method for heartwood detection for Scotch pine, which is based on the fluorescence information emitted of pinosylvin type stilbene and its monomethyl ether. Fluorescence imaging is a low-cost method for measuring heartwood content in real time on an industrial line. The method is applicable for fresh and dried samples. This paper will show the results of fluorescence matrices of Scotch pine. Measurements were made with a bispectrometer system to obtain suitable wavelengths for the excitation and detection of fluorescence. A reliable measuring system is described, which is suited for on-line measurements on an industrial line. An algorithm will also be presented, which is useful for quantification of heartwood and sapwood.

Sapwood and Heartwood Contents on the Logs and Sawn Boards of Manglid (Manglieta glauca Bl.)

The aim of this research is to identify the characteristics of sapwood and heartwood of manglid wood both in the logs and sawn boards; and to evaluate the differences of sapwood and heartwood content of sawn board from two sawing patterns: live sawing pattern and semi quarter sawing pattern. Totally 30 manglid logs coming from private forest in Sodonghilir sub-District, Tasikmalaya Regency were used as samples. About 35 sawn boards from each of sawing pattern were randomly chosen as specimens for sawn board observation. Result shows that manglid wood has thicker heartwood content than the sapwood on the log cross section, with the average of the heartwood and sapwood thickness is 17.04 and 6.57 cm, respectively. The thickness of heartwood part is positively correlated with the log diameter. Meanwhile, the percentage of the heartwood volume increases but the percentage of the sapwood decreases by the increasing of the log diameter. The higher thickness of the heartwood part compared to the sapwood part is consistent in the case of sawn board both from live sawing pattern and semi quarter pattern. Sawn board from the live sawing pattern has a lower sapwood percentage than the heartwood percentage on the width section. Key words: heartwood, live sawing, log, sapwood, semi quarter sawing

Variation in wood anatomical properties of selected indigenous, multipurpose tree species grown in research trials at LRS Thiruvazhamkunnu, Palakkad, Kerala

The present study is an attempt to study the variation in wood physical and anatomical properties of Artocarpus heterophyllus Lam., Artocarpus hirsutus Lam. and Pterocarpus marsupium Roxb. raised as part of a provenance trial of the Kerala Agricultural University at the Livestock Research Station, Thiruvazhamkunnu, in Palakkad district of Kerala. The objectives were to study the variation in bark thickness, heart wood content, specific gravity, fibre morphology, vessel morphology, and ray morphology between above species as well as to understand the radial variation within the trees under the prevailing agro climatic conditions. Results showed higher values for heart wood content, ray height, ray width, vessel frequency; and lower bark thickness in A. hirsutus, compared to the other two species while, P. marsupium had the highest air dry and oven dry specific gravity. A. heterophyllus had superior values for vessel diameter, vessel area, fibre length and fibre diameter. The information obtained from this study indicates the potential of these hitherto under-estimated multipurpose indigenous species for various end-uses. The results also points to the pertinent need to undertake long term tree improvement trials of the above species for efficient utilization of these promising species for the state of Kerala.

Biocide Retention Variation and Gradients in Commercially Treated 4 by 4s

Biocide retentions for copper-based wood preservatives used for residential ground-contact applications are established through field stake tests using small research stakes cut from selected sapwood and then treated in laboratory cylinders. The results from the relatively short-term field tests are then used to specify retentions for commercially treated timbers that have a range of densities and heartwood content. More than 120 4 by 4s that had been commercially treated with four copper-based systems readily available were purchased, with the posts carefully selected for good biocide penetration and a wide outer sapwood band, and analyzed for biocide retentions. Also, biocide gradients from five soluble copper and three particulate copper commercially treated 4 by 4s, all having the same labeled retention, were determined. All four systems gave a range of analyzed retentions, with some fraction of the timbers of each preservative system having a relatively low biocide level. In contrast to previous reports, the biocide gradient for wood treated with a soluble copper formulation was less steep than in wood treated with a particulate copper system.

Wood characteristics of Terminalia amazonia, Vochysia guatemalensis and Hyeronima alchorneoides planted in Costa Rica

The aim of the present study was to evaluate the esthetic and structural characteristics, as well as the wood decay resistance of Terminalia amazonia, Vochysia guatemalensis, and Hyeronima alchorneoides trees from fast-growth condition in a tropical humid region of Costa Rica. A total of 10 trees of T. amazonia, V. guatemalensis and H. alchorneoides each, were randomly selected for harvesting from forest plantations. Young trees of all three species showed very poor esthetic characteristics in comparison to market expectations, particularly due to their reduced heartwood content and their light dark color. Wood from plantation forest trees of V. guatemalensis, T. amazonia, and H. alchorneoides in Costa Rica showed inferior wood properties than wood from natural forests. However, age differences of trees between both provenances limit the validity of present results. Terminalia amazonia from forest plantations show very promising characteristics for industry processes due to its ease of drying, manipulation, and mechanical properties. The natural durability of species (young or mature) from humid regions of Costa Rica can be increased by means of preservation techniques such as the vacuum-pressing method, which are very convenient particularly in young trees with high content of sapwood.

The influence of heartwood on the pulping properties of Acacia melanoxylon wood

The pulping wood quality of Acacia melanoxylon was evaluated in relation to the presence of heartwood. The sapwood and heartwood from 20 trees from four sites in Portugal were evaluated separately at 5% stem height level in terms of chemical composition and kraft pulping aptitude. Heartwood had more extractives than sapwood ranging from 7.4% to 9.5% and from 4.0% to 4.2%, respectively, and with a heartwood-to-sapwood ratio for extractives ranging from 1.9 to 2.3. The major component of heartwood extractives was made up of ethanol-soluble compounds (70% of total extractives). Lignin content was similar in sapwood and heartwood (21.5% and 20.7%, respectively) as well as the sugar composition. Site did not influence the chemical composition. Pulping heartwood differed from sapwood in chemical and optical terms: lower values of pulp yield (53% vs 56% respectively), higher kappa number (11 vs. 7), and lower brightness (28% vs 49%). Acacia melanoxylon wood showed an overall good pulping aptitude, but the presence of heartwood should be taken into account because it decreases the raw-material quality for pulping. Heartwood content should therefore be considered as a quality variable when using A. melanoxylon wood in pulp industries

Effect of Wood Content on The Thermal Behavior and on The Molecular Dynamics of Wood/Plastic Composites

AbstractSummary: In the last decades, the growing environmental awareness has resulted in a renewed interest in the use of natural materials for different applications. In this context, the use of wood in plastic to obtain composites has grown significantly. In the present work, heartwood and sapwood from Angelim Pedra (Hymenolobiun petraeum) were used to prepare PVC/wood composites. To study the composites with different wood types and filler contents the molecular dynamic was investigated through low field NMR by poton spin‐ lattice relaxation time measurements (T1H) and the thermal behavior was characterized by means of differential scanning calorimetry (DSC) focusing the glass transition temperature and thermogravimetric analyses (TGA) observing the changes in the thermal stability. It was found that increasing addition of wood flour (sapwood and heartwood) caused a small but progressive improvement of the decomposition temperature of the composites, whereas the glass transition temperature remains practically unchanged. In the molecular dynamic behavior, a gradual decrease in T1H values was observed with increasing sapwood and heartwood content, indicating that the composites became less rigid. The distribution curves of the domains showed a better interaction and phase dispersion between the composite components with higher filler content.

Stem form and branchiness of Norway spruce as a sawn timber—Predicted by a process based model

A process-based growth model, PipeQual was adapted to Norway spruce ( Picea abies [L.] Karst.) for describing stand development and timber properties (stem taper, heartwood formation and branchiness). PipeQual predictions on timber properties were tested against (1) the data set used for estimating the structural and metabolic parameters of the growth model, and (2) an independent data set. Both data sets consist of two stands located in southern and central Finland. Parameter values of the PipeQual model related to tree structure were estimated on the basis of measurements of tree characteristics. The metabolic parameters of the model were calibrated on the basis of stand-level predictions of basal area, dominant height, and stem volume. In addition, statistical models for branch characteristics were incorporated in the model. The predictions of stem taper, heartwood content and branchiness were consistent with measurements. However, the model slightly overestimated stem taper curve in the upper half of the stem in thinned stands. In addition, branch diameters were underestimated in the upper half of the stem in thinned and untreated stands, while branch diameters in the lower stem were somewhat overestimated. Overall, the results suggest that the PipeQual model has potential for simulating growth and properties of a Norway spruce stand.

Quantitative co-occurrence of sesquiterpenes; a tool for elucidating their biosynthesis in Indian sandalwood, Santalum album

A chemotaxonomic approach was used to investigate biosynthetic relationships between heartwood sesquiterpenes in Indian sandalwood, Santalum album L. Strong, linear relationships exist between four structural classes of sesquiterpenes; α- and β-santalenes and bergamotene; γ- and β-curcumene; β-bisabolene and α-bisabolol and four unidentified sesquiterpenes. All samples within the heartwood yielded the same co-occurrence patterns, however wood from young trees tended to be more variable. It is proposed that the biosynthesis of each structural class of sesquiterpene in sandalwood oil is linked through common carbocation intermediates. Lack of co-occurrence between each structural class suggests that four separate cyclase enzymes may be operative. The biosynthesis of sandalwood oil sesquiterpenes is discussed with respect to these co-occurrence patterns. Extractable oil yield was correlated to heartwood content of each wood core and the oil composition did not vary significantly throughout the tree.

The influence of irrigation and fertilization on heartwood and sapwood contents in 18-year-old Eucalyptus globulus trees

The quality of wood from 18-year-old Tasmanian bluegum (Eucalyptus globulus Labill.) trees was assessed in relation to heartwood content, accumulation of extractives, and pulp yield using two growth conditions: control (C) and growth optimized by irrigation and fertilization in the first 6 years of growth (IL). Within the tree, heartwood content decreased from the base upwards, representing, on average, 77.7% and 67.6% at the base and 7.0% and 4.8% at 29.3 m height for IL and C trees, respectively. Heartwood volume represented 65.6% and 55.6% of total tree volume for IL and C trees, respectively. Heartwood content was positively correlated with tree growth, while sapwood content remained rather constant, with a radial width of approximately 2 cm. Heartwood contained more extractives than sapwood (5.3% vs. 4.0%) and pulp yield was lower from heartwood than from sapwood (58.0% vs. 56.0%). Pulp yield was negatively correlated with content of extractives. No difference in extractives or pulp yield was found between IL and C trees. The presence of heartwood decreases the quality of raw material for pulping and should be regarded as a stem-quality variable in eucalypt forestry.

Heartwood and sapwood development within maritime pine ( Pinus pinaster Ait.) stems

Heartwood and sapwood development in maritime pine (Pinus pinaster Ait.) is reported based on 35 trees randomly sampled in four sites in Portugal. It was possible to model the number of heartwood rings with cambial age. The heartwood initiation age was estimated to be 13 years and the rate of sapwood transformation into heartwood was 0.5 and 0.7 rings year−1 for ages below and above 55 years, respectively. Reconstruction of heartwood volume inside the tree stem was made by visual identification by image analysis in longitudinal boards along the sawn surfaces. This volume was integrated into the 3D models of logs and stems developed for this species representing the external shape and internal knots. Heartwood either follows the stem profile or shows a maximum value at 3.8 m in height, on average, while sapwood width is greater at the stem base and after 3 m remains almost constant up the stem. Up to 50% of tree height heartwood represents 17% of stem volume, in 83-year-old trees and 12–13% in 42 to 55-year-old trees. Tree variables such as stem diameter, DBH and tree total height were found to correlate significantly with the heartwood content.

Pine heartwood formation as a maturation phenomenon

The inverse of the relative increment rate of size is proposed as a measure of the maturity of a forest tree. The heartwood content within bole cross sections is modeled semiempirically using asymptotic fitting. It is shown that the present proposal for a definition of maturity statistically explains heartwood content far better than age or size. The heartwood content appears to be independent on growth rate and tree size.

Cement Hydration Tests Using Wood Flour may not Predict the Suitability of Acacia mangium and Eucalyptus pellita for the Manufacture of Wood-Wool Cement Boards

Summary Wood-wool cement boards (WWCBs) are manufactured in many tropical countries which have extensive eucalypt and acacia plantations. Wood from such plantations could act as a potential raw material for WWCBs, but the suitability of most tropical eucalypts and acacias for the manufacture of such products is unknown. This study was undertaken to assess whether the standard laboratory test for wood-cement compatibility, which measures heat of hydration in wood flour-cement mixtures, is an appropriate method for screening tropical eucalypts and acacias for their compatibility with cement and suitability for the manufacture of WWCBs. Wood samples from a tropical eucalypt (E. pellita) and a tropical acacia (A. mangium) were tested in two forms, i. e. flour and wool, for their compatibility (expressed by maximum hydration temperature and CA-factor) with Portland cement. Form significantly influenced the effect of the wood on cement hydration, resulting in a different species compatibility ranking for flour and wool. As the heartwood content of wood-wool-cement hydration test samples increased, Tmax. and CA factor increased whereas the opposite occured for those containing wood flour. Tests using wood flour ranked E. pellita as being more compatible with cement than A. mangium whereas the ranking was reversed when wood-wool was used. Furthermore at low wood levels the compatibility of samples containing wood-wool or wood flour with cement was similar whereas at high wood levels, samples containing wood-wool were much more compatible with cement than those containing wood flour. Laboratory tests designed to screen eucalypts and acacias for their compatibility with cement should use wood in a coarser form with a lower surface-to-volume ratio than flour. Caution should be exercised if using results from wood flour-cement hydration tests to estimate the suitability of wood species for the manufacture of WWCBs and possibly other wood-cement composites.

Development of a method for sorting picea abies pulp wood with respect to basic density

The basic density of pulp wood can be used to convert green volume to dry weight, and as an indicator of the fibre quality. Because the methods for measuring basic density are cumbersome, a practical, on‐line method for sorting Norway spruce pulp wood with respect to basic density was developed. The relationship between mean annual ring width and basic density was used to sort the pulp wood. Brief visual inspection could separate piles of logs with different mean annual ring widths from each other with an acceptable precision. The resulting classes had significantly different mean basic densities (380, 400 and 434 kg m−3). Means of other properties, such as juvenile wood content, heartwood content, and dry matter content, also differed among classes.

Effect of Genotype-by-Environment Interaction on the Wood Properties and Qualities of Four-year-oldEucalyptus grandisandE. grandisHybrids

SYNOPSIS The effect of environment on growth-stress splitting, wood density, fibre length, shrinkage and heartwood content was studied using 31 five-year-old eucalypt clones, mostly Eucalyptus grandis and E. grandis-based hybrids, grown in replicated trials at 26 sites. An analysis of variance was carried out for each wood property to test the interaction between site and clone. For each clone a linear regression of the individual property value on the mean of all clones for each site was computed as a further measure of clone-by-site interaction. Both analyses indicated that genotype-by-environment interaction does exist for some clones and that it is applicable to all the wood properties considered except fibre length. However, clones showing sensitivity to changes in the environment for a particular wood property did not necessarily show sensitivity in the case of other wood properties. In other words, no clone could be singled out for showing sensitivity towards changes in the environment for all its ...