The influence of heartwood extractives on wood density patterns in tree stems

The influence of heartwood extractives on wood density patterns in tree stems | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report The influence of heartwood extractives on wood density patterns in tree stems Clemens Michael Altaner This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6844932/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Context : Wood density varies within stems from pith to bark and base to top. Wood density is the combination of cell walls and extractives, each factor controlling different wood properties. Understanding the distribution of heartwood extractives is critical for species grown for their heartwood. Aims : Heartwood compounds are resource intensive to quantify by chemical extraction and have been rarely considered in studies of within stem wood density patterns. The objective was to disentangle the contributions of cell walls and extractives to within stem density patterns without the need for extraction. Methods: By sampling Eucalyptus bosistoana F.Muell. and Eucalyptus globoidea Blakely trees across a wide age-range, wood density of heartwood and sapwood was measured for all within-stem positions. Statistical modelling allowed to quantify the contributions of cell walls and heartwood extractives to specie-specific within-stem density patterns. Results : Heartwood extractives had a significant effect on wood density for the two species. The within-stem patterns differed between species and were complex. Conclusion Strategically sampling wood density for a wide age-range of trees allows to deduce the complex specie-specific within stem patterns of heartwood extractives and cell walls, without the laborious task of wood extraction. This improves our understanding of wood quality. Coast grey box Eucalyptus bosistoana F.Muell. Eucalyptus globoidea Blakely sapwood white stringybark Figures Figure 1 Figure 2 Figure 3 Key message Cell walls and extractives contribute independently to wood density. The two components control different wood properties, such as strength or durability, respectively. However, extractive measurements are laborious hindering studying typical within-stem distributions. Strategic sampling of heartwood and sapwood density allowed the determination of the individual contributions to the complex within-stem wood density patterns without the need for chemical extraction. 1. Introduction The density of wood can range from less than 100 kg m − 3 to more than 1300 kg m − 3 (Zanne, Lopez-Gonzalez et al., 2009 ). Variation is not only found between species but also within a specie. Typical species-specific radial and axial wood density gradients have been described (Schimleck, Dahlen et al., 2025 ). For example wood density doubles in Eucalyptus robusta Sm. from less than 400 kg m − 3 at the centre base of the stem to over 800 kg m − 3 at the periphery of the top log (Skolmen, 1972 ). Wood density is in the first instant controlled by the volume of pores, i.e. cell lumen, as the cell wall material is of almost constant density (Kellogg and Wangaard, 1969 ). The deposition of plant cell walls is controlled by the cambium during xylem formation. For trees which form heartwood, in an independent secondary process extractives can be deposited into the porous wood structure (Hillis, 1987 ). As in some timber species heartwood extractives can make up close to 30% of the mass (Hillis, 1987 ; Fengel, 1991 ) the density of their sapwood, predominantly made up of cell walls, will differ from that of their heartwood, a mixture of cell walls and secondarily deposited extractives. The two independent contributions to wood density, cell walls and extractives, affect different wood properties and consequently wood utilisation. For example, mechanical and pulp properties should be mainly affected by cell walls (Hillis, 1978 ; Ona, Sonoda et al., 1997 ), while wood features such as colour, natural durability or heating value are mainly under the control of extractives (Taylor, Gartner et al., 2002 ; Telmo and Lousada, 2011 ). Carbon sequestration is affected by both. Separating these two independent biological processes’ contributions to wood density is useful for species with higher extractive content when investigating wood quality (Hillis, 1978 ; Lehnebach, Bossu et al., 2019 ). Cell wall density was assessed for mapping pulp properties (Ona, Sonoda et al., 1997 ; Ona, Sonoda et al., 1998 ) or extractive content when investigating natural durability (Nelson and Heather, 1972 ). Regarding typical species-specific density patterns, this was either achieved by removing extractives by solvent extraction (Nelson and Heather, 1972 ; Wilkins and Horne, 1991 ; Ona, Sonoda et al., 1997 ; Ona, Sonoda et al., 1998 ) or focusing on young trees where heartwood formation had not started (Gonçalves, Lorensani et al., 2019 ). While the former is labour intensive, the latter cannot be used for older, heartwood-containing trees. As the contribution of extractives is the difference of sapwood and heartwood density, it should, however, be possible to deduce the individual contributions of cell walls and heartwood extractives from density data. This will require local density measurements of sapwood and heartwood on all positions across the stems. These can be obtained if a wide range of tree sizes/ages is sampled for wood density and the wood type is recorded. Such a sample set became available in the course of a biomass study of Eucalyptus bosistoana F.Muell. and Eucalyptus globoidea Blakely. The objective of this study was to demonstrate that typical specie-specific patterns for cell walls and extractive content can be obtained without labour intensive solvent extraction by statistical modelling of local heartwood and sapwood density data from trees spanning a wide age/size range. Within stem patterns of heartwood extractives have been documented (Sherrard and Kurth, 1933 ) and have been described to typically increase from the pith to the heartwood-sapwood boundary and being more abundant further up the stem (Hillis, 1987 ). Radial gradients in heartwood extractives have also been found in branches (Terrasse, Brancheriau et al., 2021 ). Heartwood extractives are associated with decay resistance (Hawley, Fleck et al., 1924 ) and durability standards regard inner heartwood as less durable than outer heartwood from old-growth trees (AS5604, 2005 ). It appears that these typical specie-specific heartwood extractive content patterns have not been quantitatively modelled. Eucalyptus globoidea and E. bosistoana are emerging plantation species with fast-growth (Boczniewicz, Mason et al., 2022 ). Their dens and ground-durable heartwood (Poynton, 1979 ; Poynton, 1979 ; Bootle, 2005 ) is suited for structural (Guo and Altaner, 2018 ), out-door (Millen, Altaner et al., 2018 ) and biomass products. Extractive contents of up to 15% were reported for E. globoidea and E. bosistoana in their heartwood (Li and Altaner, 2019 ). Considering their applications, cell wall, extractive and total density are relevant properties. However, little is known about the wood density variations of these species. 2. Material and methods 2.1. Material Stem discs of E. bosistoana and E. globoidea trees were obtained during biomass and taper studies of the species. A detailed description of the sites, trees and field sampling procedures is available elsewhere (Boczniewicz, Mason et al., 2022 ; Mason, Millen et al., under review). This study was based on stem discs from 74 E. bosistoana originating from eight sites felled when 2- to 20-years-old, and 63 E. globoidea trees originating from five sites felled when 7- to 29-years-old (Table 1 ). Stem discs were cut at variable height depending on taper increments (Boczniewicz, Mason et al., 2022 ) and oven-dried. Heartwood was highlighted by applying methyl orange pH indicator. Table 1 Sites information and summary statistics of wood density data for E. bosistoana and E. globoidea . Different letters indicate Tukey HSD significance (P = 0.01) between wood types in each site. E. bosistoana Sites Coordinates Number of trees Tree age (years) Wood type Number of blocks Mean wood density (sd) (kg/m 3 ) Cravens 41°26’S 173°56’E 12 14 SW 126 880.4 (61.0) a HW 70 952.2 (48.2) b Mix 132 945.0 (51.8) b Dillon 41°66′S 173°67′E 3 5 SW 20 837.1 (41.0) HW 0 - Mix 0 - Flemming 43°11’S 172°39’E 17 20 SW 139 849.7 (54.0) a HW 31 940.2 (46.0) b Mix 80 898.0 (53.5) c Holdaway 41°39’S 173°18’E 7 2 SW 24 757.6 (118.7) HW 0 - Mix 0 - Lawsons 41°43’S 174°02’E 15 14 SW 166 888.2 (47.8) a HW 22 985.3 (58.6) b Mix 98 957.4 (48.9) c MacBeth 42°47’S 173°11’E 1 9 SW 10 893.6 (52.0) HW 0 - Mix 0 - Pukaka 41°24’S 174°00’E 13 20 SW 157 895.1 (58.9) a HW 136 971.2 (44.7) b Mix 182 945.4 (45.1) c Waikakaho 41°25’S 173°54’E 6 18 SW 89 827.2 (57.1) a HW 80 910.9 (69.3) b Mix 91 884.5 (54.6) c Total 74 2 to 20 SW 731 868.0 (65.9) a HW 339 951.1 (58.5) b Mix 582 931.3 (56.6) c E. globoidea Sites Coordinates Number of trees Tree age (years) Wood type Number of blocks Avery 41°46’S 174°08’E 8 12 SW 54 639.2 (48.5) a HW 23 831.2 (43.9) b Mix 89 727.6 (78.0) c Ettrick 43°47’32.0’’S 172°50’20.8’’E 26 29 SW 322 618.6 (73.3) a HW 1005 664.5 (87.4) b Mix 262 696.0 (76.4) c JNL 41°02’42.7’’S 175°52’37.2’’E 5 7 SW 106 568.8 (61.2) a HW 33 701.3 (46.6) b Mix 12 644.7 (41.2) c MacBeth 42°47’S 173°11’E 11 9 SW 118 610.5 (62.1) a HW 6 771.7 (72.9) b Mix 118 685.4 (65.3) c Pukaka 41°24’S 174°00’E 13 17 SW 234 645.5 (51.4) a HW 330 712.6 (59.0) b Mix 220 688.1 (60.6) c Total 63 7 to 29 SW 834 620.0 (67.3) a HW 1397 679.9 (85.3) b Mix 626 696.0 (71.6) c 2.2. Density A 2.5 cm wide full diameter strip including the pith was split from each of the 3–5 cm thick stem disc. These strips were further split into wood blocks, 2.5 x 2.5 cm in cross-section, starting with a block centred over the pith. Wood blocks were dried at 103°C before each block was weighed and the heartwood percentage of each block was estimated to the nearest 10%. The volume of each block was then determined by immersion weighing in water. Dry density was calculated as the ratio of dry mass and dry volume. 2.3. Data analysis Data was analysed with the R software (R Core Team, 2022 ). For analysing the site effect on heartwood density without confounding of tree age, only heartwood samples centred at the pith within the first 0.5 m stem height were considered. Tukey HSD tests were used to test significance (p = 0.01) of differences between groups. Linear mixed effect models were calculated with the lmer function of the lme4 package (Bates, Mächler et al., 2015 ). The model for dry wood density of each species considered distance from the pith (cm), disc height (m) and heartwood (%) as well as their two-way interactions, and site as fixed effects. Potential correlations in observations taken from the same tree were accounted for by including tree as a random effect. 3. Results The mean dry heartwood density of the E. bosistoana tress in this study was 951 kg m -3 (Table 1). Considering the published tangential movement of 0.42% per % change in moisture content (MC) (AS1720.2, 2006) and a radial to tangential movement ratio of 1 : 2, this equated to approximately 1000 kg m -3 at 12% MC. The mean dry sapwood density of 868 kg m -3 (Table 1) equated to ~900 kg m -3 at 12% MC. Dry density of the E. globoidea heartwood was 680 kg m -3 (Table 1) or approximately 710 kg m -3 at 12% (MC) considering 0.36% per % MC change (AS1720.2, 2006). The average sapwood dry density of the E. globoidea trees was 620 kg m -3 (Table 1), equating to approximately 640 kg m -3 at 12% MC. 3.1. Site effect Site means of heartwood dry density at the centre base of the stem, that is within 13 mm of the pith and below 0.5 m stem height, ranged between 902 and 1006 kg m -3 for E. bosistoana and 689 and 843 kg m -3 for E. globoidea , respectively (Fig. 1). The difference among sites was statistically significant (P = 0.01) for both species. The same analysis for sapwood suffered from limited observations at a given stem position across sites, giving low confidence in the results. 3.2. Radial and axial density patterns The data allowed to investigate the effects of height, distance from the pith, heartwood extractives and site on dry wood density for E. bosistoana and E. globoidea . All effects including the two-way interactions between stem height, distance from the pith and extractive content were significant (Table 2). The models revealed complex typical specie-specific density patterns within the stem. Individual contributions of cell walls and extractives differed between the two species. For E. bosistoana the sapwood density, i.e. the contribution of the cell walls, had negative coefficients for stem height and distance from the pith and a positive interaction term between the two (Table 2), resulting in a saddle like pattern with lower density at the top of the stem and the outer stem base (Fig. 2). The contribution of heartwood extractives increased with distance from the centre base of the stem, i.e. terms for stem height, distance to the pith and their interaction were positive (Table 2). The resulting heartwood density pattern within the stems, i.e. the combination of cell walls and heartwood extractives, was complex with the radial density gradient dependent on the height (Fig. 2). The within stem wood density patterns of E. globoidea differed from those of E. bosistoana (Fig. 3). Sapwood density, i.e. the contribution of cell walls, increased with distance from the centre base of the stem, i.e. had positive terms for height, distance from the pith as well as their interaction (Table 2). Also, in contrast to E. bosistoana , heartwood extractives decreased with stem height and distance from the pith, ie heartwood related terms were negative (Table 2). For both species, the significance of site on wood density described in section 3.1 was also reflected in the significance of site terms in this model (Table 2). Table 2 Fixed effect estimates on within stem dry density of E. bosistoana and E. globoidea . Significance levels: * p < 0.05; ** p < 0.01 and *** p < 0.001. Fixed effects E. bosistoana E. globoidea Intercept (kg m -3 ) 931*** 648*** Radius (kg m -3 cm -1 ) -4.43*** 7.17*** Disk height (kg m -3 m -1 ) -5.40*** 3.97*** Interaction of radius and disk height (kg m -3 cm -2 m -1 ) 0.888*** 0.244*** Heartwood (kg m -3 ) 37*** 118*** Interaction of heartwood and radius (kg m -3 cm -1 ) 5.43*** -2.33*** Interaction of heartwood and disk height (kg m -3 m -1 ) 3.84*** -1.68*** Site (kg m -3 ) MacBeth Pukaka Waikakaho Dillon Flemming Holdaway Lawsons -23.6 6.6 -52.0** -88.1*** -52.4*** -166*** -7.65 MacBeth Pukaka Ettrick JNL -47.3* -69.4** -125*** -101*** 4. Discussion Densities at 12% MC have been published for E. bosistoana heartwood from old-growth Australian forests (1100 kg m − 3 ) (AS1720.2, 2006 ) and heartwood from 42-year-old trees grown in Urugay (942 kg m − 3 ) (Mantero, O’Neill et al., 2014 ). The less than 20-year-old NZ-grown E. bosistoana tress in this study were with a heartwood density of ~ 1000 kg m − 3 (section 3) denser than the timber grown in Urugay. The mean sapwood density (~ 900 kg m − 3 at 12% MC) was higher than the reported 816 kg m − 3 for 2-year-old seedings of this species (Davies, 2019 ). Density of the E. globoidea heartwood was with 710 kg m − 3 at 12% MC considerably lower than the 850 kg m − 3 reported for heartwood sourced from old-growth Australian forests (AS1720.2 2006 ). It, however, fell in the reported range (640 to 830 kg m − 3 ) for the species by Ilic ( 2002 ) and NZ-grown plantation trees aged 30-year-old (690 kg m − 3 ) (Guo and Altaner, 2018 ), 28-year-old (720 kg m − 3 ) (Scown, Lim et al., 2023 ), or 25-year-old (655 kg m − 3 ) (Jones, McConnochie et al., 2010 ). Sapwood density of approximately 640 kg m − 3 at 12% MC, was similar to that reported for tops of 7-year-old trees (600–630 kg m − 3 ) but was lower than that of 2-year-old coppice (660 kg m − 3 ) (Iyiola, 2021 ). It should be noted that the differences discussed above are a combination of both, site and tree age. In average. heartwood for both species was denser than its sapwood (Tabel 1). The 83 kg m − 3 and 60 kg m − 3 for E. bosistoana and E. globoidea , respectively. Ignoring radial or axial gradients described below, this suggested an extractive content of ~ 9% in the heartwood. This was plausible, as the ethanol soluble extractive fraction made up ~ 5% (ranging up to 14%) of the heartwood in young 7-year-old E. bosistoana and 5- to 80-year-old E. globoidea trees (Li, Apiolaza et al., 2018 ). 4.1. Site effect Site and tree age was confounded in this data set. However, in contrast to previous studies reporting whole tree density (McKinley, Shelbourne et al., 2000 ), by comparing wood density at a fixed position in the stem, it was possible to remove the confounding age effect and test for site effects. The site effect on heartwood density at the centre base of the stem was significant in this study (Fig. 1 ). Site effects on wood density are well known for other tree species (Raymond and Muneri, 2001 ; Kimberley, Cown et al., 2015 ; Hein, Chaix et al., 2016 ; Vega, Hamilton et al., 2020 ), but had not been confirmed for E. bosistoana and E. globoidea . It was not possible to differentiate the contributions of cell walls and heartwood extractives, as the study lacked sapwood data for this within stem location. It is likely that both factors are site dependent. Site difference in heartwood extractive contents for replicated breeding trials of E. bosistoana have been detected (Li, Apiolaza et al., 2018 ) and are relevant for spices grown for their durable heartwood. The available data did not allow to investigate environmental variables influencing wood density in these species. 4.2. Radial and axial density patterns within stems Axial and radial gradients of wood density have been reported for eucalypts (Hillis, 1978 ). Consistent with this study, Frederick, Madgwick et al. ( 1982 ) reported distinct radial profiles at different heights of the stem for heartwood of 17-year-old E. regnans F.Muell. trees but contributions of cell walls and heartwood extractives were not separated. Complex within stem sapwood density patterns have also been recorded for young Eucalyptus grandis W.Hill ex Maiden and its hybrid with Eucalyptus urophylla S.T.Blake (Wilkins and Horne, 1991 ; Hein, Chaix et al., 2016 ). But these studies did not quantified the effects of stem height and distance from the pith. Typical specie-specific radial density patters in heartwood of some eucalypt species have been quantified as relevant wood property for rotary peeled veneer (McGavin, Bailleres et al., 2015 ; Vega, Hamilton et al., 2020 ). Neiter study quantified the effect of heartwood extractives. It is worth mentioning that the linear nature of the used mixed effect model in this study does not allow extrapolation to larger trees, as density gradients approach a maximum asymptote in mature trees. The developed models are applicable for short-rotation plantations, but more complex function such as the sigmoidal functions used by McGavin, Bailleres et al. ( 2015 ) might be needed for larger trees. 4.3. Within stem heartwood extractive patterns The with distance from the centre base of the stem observed increasing heartwood extractive content in E. bosistoana matched the commonly described pattern for a range of tree species (Hillis, 1987 ). Higher amounts of extractives were reported for outer than inner heartwood of Eucalyptus marginata Sm. (Hillis, 1956 ), or E. grandis (Bamber, Floyd et al., 1969 ). It appears that no decreasing radial or axial gradients in heartwood extractives have been reported in literature and in this sense E. globoidea seems to be unique. But the polyphenol content in heartwood of E. grandis was found to be not affected by sampling height in the 5 innermost annual rings (Bamber, Floyd et al., 1969 ). The radially decreasing resin content in softwoods (Uprichard and Lloyd, 1980 ) is unrelated to heartwood extractives as softwood resins are synthesised in epithelial cells able to flow through the stem in the resin canal network (Govina, Apiolaza et al., 2021 ) and not fixed in space like heartwood extractives after deposition in the cell walls when sapwood transforms into heartwood in the transition zone. Site was also reported to affect the amount of heartwood extractives of Eucalyptus globulus Labill. (Pereira, 1988 ; Morais and Pereira, 2012 ). 5. Conclusion The study demonstrated the complexity of within-stem wood density patterns in E. bosistoana and E. globoidea . Heartwood extractives significantly influence density variations, with distinct radial and axial gradients differing between species. Site effects further shape these patterns. Contributions of cell walls and heartwood extractives and can be deduced from sapwood and heartwood density without the need for chemical extraction, if both data are available across the stem. Wood properties related to cell walls such as strength, and those related to heartwood extractives such as durability are expected to correlate better with the individual density contributions rather than the commonly reported heartwood patterns. If wood density maps are used to predict wood properties for species featuring high extractive contents, the individual contributions should be considered. Declarations Competing Interests The author has no financial interests to disclose. Clemens Altaner is a director of New Zealand Dryland Forests IP Limited. Author Contribution C.A. conceived the study, analyzed the data and wrote the manuscript. Acknowledgement I thank Georgia Kennedy, Christophe Robert, Monika Sharma, Maxime Ponsoda, Kura Ngahere | School of Forestry, Te Whare Wānanga O Waitaha | University of Canterbury, for measuring density and heartwood, and Luis Apiolaza, Kura Ngahere | School of Forestry, Te Whare Wānanga O Waitaha | University of Canterbury, for statistical advice. Data Availability Data is provided within the manuscript or supplementary information files. References AS1720.2, 2006. Timber structuresPart 2: Timber properties, Australian Standard,pp. 20. AS5604, 2005. Timber - Natural durability ratings, Australian Standard. Bamber R.K., A.G. Floyd, et al., 1969. Wood properties of flooded gum. Austral. For. 33(1): 3-12. Bates D., M. Mächler, et al., 2015. Fitting Linear Mixed-Effects Models Using lme4. Journal of Statistical Software, 67(1): 1-48. Boczniewicz D., E.G. Mason, et al., 2022. Developing fully compatible taper and volume equations for all stem components of Eucalyptus globoidea Blakely trees in New Zealand. New Zealand Journal of Forestry Science 52(6). Bootle K.R., 2005. Wood in Australia. Types, properties, and uses, McGraw-Hill Australia, 452 p. Davies N.T., 2019. High throughput breeding for wood quality improvement, University of Canterbury, Christchurch, New Zealand,pp. 191. Fengel D., 1991. Chemical studies on the wood of quebracho colorado (schinopsis balansae engl.) part 1. composition of sapwood and heartwood. Holzforschung 45(4): 259-263. Frederick D.J., H.A.I. Madgwick, et al., 1982. Wood basic density and moisture content of young Eucalyptus regnans grown in New Zealand New Zealand Journal of Forestry Science 12(3): 494-500. Gonçalves R., R.G.M. Lorensani, et al., 2019. Evolution of acoustical, geometrical, physical, and mechanical parameters from seedling to cutting age in Eucalyptus clones used in the pulp and paper industries in Brazil. Forest Products Journal 69(1): 5-16. Govina J.K., L.A. Apiolaza, et al., 2021. Variation and genetic parameters of axial resin canal features in clones and families of Pinus radiata . New For. 52(1): 167-176. Guo F. and C.M. Altaner, 2018. Properties of rotary peeled veneer and laminated veneer lumber (LVL) from New Zealand grown Eucalyptus globoidea. New Zealand Journal of Forestry Science 48(3): 10. Hawley L.F., L.C. Fleck, et al., 1924. The relation between durability and chemical composition in wood. Ind Eng Chem 16: 699-700. Hein P.R.G., G. Chaix, et al., 2016. Spatial variation of wood density, stiffness and microfibril angle along Eucalyptus trunks grown under contrasting growth conditions. Trees-Struct. Funct. 30(3): 871-882. Hillis W., 1956. Leucoanthocyanins as the possible precursors of extractives in woody tissues. Australian Journal of Biological Sciences 9(2): 263-280. Hillis W.E., 1978. Wood quality and utilization. In: Hillis W. E. and Brown A. G. (Eds.), Eucalypts for wood production, CSIRO, Adelaide, Australia,pp. 259-289. Hillis W.E., 1987. Heartwood and tree exudates, Springer Verlag, Berlin, 268 p. Ilic J., 2002. Woods of Eucalyptus - Part 2 - Distinguishing species from the stringybark group (E-baxteri, E-globoidea, E-muelleriana, E-macrorhyncha, E-consideniana and E-sieberi). Iawa J. 23(3): 305-318. Iyiola E.A., 2021. Wood quality of durable eucalypts. Jones T.G., R.M. McConnochie, et al., 2010. Sawing and grade recovery of 25-year-old Eucalyptus fastigata, E. globoidea, E. muelleriana and E. pilularis. New Zealand Journal of Forestry Science 40: 19-31. Kellogg R.M. and F.F. Wangaard, 1969. Variation in The Cell-Wall Density of Wood Wood and Fiber Science (3): 180-204. Kimberley M., D. Cown, et al., 2015. Modelling variation in wood density within and among trees in stands of New Zealand-grown radiata pine. New Zealand Journal of Forestry Science 45(1): 22. Lehnebach R., J. Bossu, et al., 2019. Wood Density Variations of Legume Trees in French Guiana along the Shade Tolerance Continuum: Heartwood Effects on Radial Patterns and Gradients. Forests 10(2): 80. Li Y. and C. Altaner, 2019. Calibration of near infrared spectroscopy (NIRS) data of three Eucalyptus species with extractive contents determined by ASE extraction for rapid identification of species and high extractive contentsHolzforschung,pp. 537. Li Y., L.A. Apiolaza, et al., 2018. Genetic variation in heartwood properties and growth traits of Eucalyptus bosistoana. Eur. J. For. Res. 137(4): 565-572. Mantero C., H. O’Neill, et al., 2014. Propiedades físicas y mecánicas de la madera de una población de Eucalyptus bosistoana F. Muell. cultivada en Uruguay. Agrociencia Uruguay 18(1): 65-74. Mason E.G., P. Millen, et al., under review. Modelling above-ground biomass of Eucalyptus bosistoana and Eucalyptus globoidea . New Zealand Journal of Forest Science. McGavin R.L., H. Bailleres, et al., 2015. Stiffness and Density Analysis of Rotary Veneer Recovered from Six Species of Australian Plantation Hardwoods. Bioresources 10(4): 6395-6416. McKinley R.B., C.J.A. Shelbourne, et al., 2000. Variation in whole-tree basic wood density for a range of plantation species grown in New Zealand. NZ Journal of Forestry Science 30(3): 436-446. Millen P., C. Altaner, et al., 2018. Naturally durable timber posts performing well. New Zealand Tree Grower 39(1): 24-26. Morais M.C. and H. Pereira, 2012. Variation of extractives content in heartwood and sapwood of Eucalyptus globulus trees. Wood Science and Technology 46(4): 709-719. Nelson N.D. and W.A. Heather, 1972. Wood color, basic density, and decay resistance in heartwood of fast-grown Eucalyptus grandis Hill ex Maiden. 26(2): 54-60. Ona T., T. Sonoda, et al., 1997. Relationship between various extracted basic densities and wood chemical components in Eucalyptus camaldulensis. Wood Science and Technology 31(3): 205-216. Ona T., T. Sonoda, et al., 1998. Relations between various extracted basic densities and wood chemical components in Eucalyptus globulus. Journal of Wood Science 44(3): 165-168. Pereira H., 1988. Variability in the Chemical-Composition of Plantation Eucalypts (Eucalyptus-Globulus Labill). Wood and Fiber Science 20(1): 82-90. Poynton R.J., 1979. Eucalyptus bosistoana F. Mueller. In: Poynton R. J. (Ed.) Tree Planting in Southern Africa: The eucalypts, Department of Forestry, South Africa,pp. 101-106. Poynton R.J., 1979. Eucalyptus globoidea Blakely. In: Poynton R. J. (Ed.) Tree Planting in Southern Africa: The eucalypts, Department of Forestry, South Africa,pp. 316-324. R Core Team, 2022. R: A language and environment for statistical computing, R Foundation for Statistical Computing, Vienna, Austria. Raymond C.A. and A. Muneri, 2001. Nondestructive sampling of Eucalyptus globulus and E. nitens for wood properties. I. Basic density. Wood Science and Technology 35(1-2): 27-39. Schimleck L., J. Dahlen, et al., 2025. Maps depicting the within-tree wood property variation of some North American conifers: a review. Canadian Journal of Forest Research 55: 1-14. Scown H., H. Lim, et al., 2023. Machinability of plantation-grown Eucalyptus globoidea timber. Wood Material Science & Engineering: 1-6. Sherrard E.C. and E.F. Kurth, 1933. Distribution of extractive in redwood - Its relation to durability. Ind Eng Chem 25: 300-302. Skolmen R.G., 1972. Specific gravity variation in robusta eucalyptus grown in Hawaii. In: Station P. S. F. R. E. (Ed.) Res. Paper PSW-RP-78, Forest Service, U.S. Department of Agriculture, Berkeley, CA,pp. 7. Taylor A.M., B.L. Gartner, et al., 2002. Heartwood formation and natural durability - a review. Wood and Fiber Science 34(4): 587-611. Telmo C. and J. Lousada, 2011. The explained variation by lignin and extractive contents on higher heating value of wood. Biomass and Bioenergy 35(5): 1663-1667. Terrasse F., L. Brancheriau, et al., 2021. Density, extractives and decay resistance variabilities within branch wood from four agroforestry hardwood species. iForest - Biogeosciences and Forestry 14(3): 212-220. Uprichard J.M. and J.A. Lloyd, 1980. Influence of tree age on the chemical composition of radiata pine. New Zealand Journal of Forestry Science 10(3): 551-557. Vega M., M. Hamilton, et al., 2020. Radial variation in modulus of elasticity, microfibril angle and wood density of veneer logs from plantation-grown Eucalyptus nitens. Ann. For. Sci. 77(3): 65. Wilkins A.P. and R. Horne, 1991. Wood-density variation of young plantation-grown Eucalyptus grandis in response to silvicultural treatments. For. Ecol. Manage. 40(1-2): 39-50. Zanne A.E., G. Lopez-Gonzalez, et al., 2009. Data from: Towards a worldwide wood economics spectrum. In: Dryad (Ed.). Additional Declarations Competing interest reported. The author has no financial interests to disclose. Clemens Altaner is a director of New Zealand Dryland Forests IP Limited. Supplementary Files WoodDryDensity.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6844932","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":489765022,"identity":"57a63d06-295a-4c2a-8cb0-386b2b67e345","order_by":0,"name":"Clemens Michael Altaner","email":"data:image/png;base64,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","orcid":"","institution":"University of Canterbury","correspondingAuthor":true,"prefix":"","firstName":"Clemens","middleName":"Michael","lastName":"Altaner","suffix":""}],"badges":[],"createdAt":"2025-06-08 00:38:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6844932/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6844932/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":87554663,"identity":"74749d8a-d14d-46fa-8785-8b2c4db5bd1a","added_by":"auto","created_at":"2025-07-25 06:47:08","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":67775,"visible":true,"origin":"","legend":"\u003cp\u003eBox plots of heartwood dry density at the center (within 13 mm of the pith) base (below 0.5 m stem height) of for \u003cem\u003eE. bosistoana\u003c/em\u003eand \u003cem\u003eE. globoidea\u003c/em\u003e at different sites. Different letters indicate Tukey HSD significance (P = 0.01) between sites for each species.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6844932/v1/9e4cd14d6e339bb7a6503eba.jpg"},{"id":87554080,"identity":"3f956c92-44fd-4de6-812c-8d58a7a17f37","added_by":"auto","created_at":"2025-07-25 06:39:08","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":47662,"visible":true,"origin":"","legend":"\u003cp\u003eWithin stem dry density patterns for \u003cem\u003eE. bosistoana\u003c/em\u003e for heartwood, sapwood and heartwood extractives.\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6844932/v1/596b2bd76b9939e70a193f86.jpg"},{"id":87554082,"identity":"6dd02b35-ad15-4bd0-93e3-adde4e8b2038","added_by":"auto","created_at":"2025-07-25 06:39:08","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":43448,"visible":true,"origin":"","legend":"\u003cp\u003eWithin stem dry density patterns for \u003cem\u003eE. globoidea\u003c/em\u003efor heartwood, sapwood and heartwood extractives.\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6844932/v1/bf90920dd9fc142ad340fa5d.jpg"},{"id":90023384,"identity":"3794df45-353e-442a-aaea-a70ba974a616","added_by":"auto","created_at":"2025-08-27 13:38:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":944135,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6844932/v1/052edb90-79b6-4226-bab3-09222d30e7e4.pdf"},{"id":87554084,"identity":"63a8c34c-1adf-4482-9d37-bd40d4a51938","added_by":"auto","created_at":"2025-07-25 06:39:08","extension":"xlsx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":271615,"visible":true,"origin":"","legend":"","description":"","filename":"WoodDryDensity.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-6844932/v1/dce1496650da5600be13a228.xlsx"}],"financialInterests":"Competing interest reported. The author has no financial interests to disclose. Clemens Altaner is a director of New Zealand Dryland Forests IP Limited.","formattedTitle":"The influence of heartwood extractives on wood density patterns in tree stems","fulltext":[{"header":"Key message ","content":"\u003cp\u003eCell walls and extractives contribute independently to wood density. The two components control different wood properties, such as strength or durability, respectively. However, extractive measurements are laborious hindering studying typical within-stem distributions. Strategic sampling of heartwood and sapwood density allowed the determination of the individual contributions to the complex within-stem wood density patterns without the need for chemical extraction.\u003c/p\u003e"},{"header":"1. Introduction","content":"\u003cp\u003eThe density of wood can range from less than 100 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e to more than 1300 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e (Zanne, Lopez-Gonzalez et al., \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Variation is not only found between species but also within a specie. Typical species-specific radial and axial wood density gradients have been described (Schimleck, Dahlen et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). For example wood density doubles in \u003cem\u003eEucalyptus robusta\u003c/em\u003e Sm. from less than 400 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e at the centre base of the stem to over 800 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e at the periphery of the top log (Skolmen, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e1972\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eWood density is in the first instant controlled by the volume of pores, i.e. cell lumen, as the cell wall material is of almost constant density (Kellogg and Wangaard, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e1969\u003c/span\u003e). The deposition of plant cell walls is controlled by the cambium during xylem formation. For trees which form heartwood, in an independent secondary process extractives can be deposited into the porous wood structure (Hillis, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e1987\u003c/span\u003e). As in some timber species heartwood extractives can make up close to 30% of the mass (Hillis, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e1987\u003c/span\u003e; Fengel, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e1991\u003c/span\u003e) the density of their sapwood, predominantly made up of cell walls, will differ from that of their heartwood, a mixture of cell walls and secondarily deposited extractives.\u003c/p\u003e\u003cp\u003eThe two independent contributions to wood density, cell walls and extractives, affect different wood properties and consequently wood utilisation. For example, mechanical and pulp properties should be mainly affected by cell walls (Hillis, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e1978\u003c/span\u003e; Ona, Sonoda et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e1997\u003c/span\u003e), while wood features such as colour, natural durability or heating value are mainly under the control of extractives (Taylor, Gartner et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2002\u003c/span\u003e; Telmo and Lousada, \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Carbon sequestration is affected by both.\u003c/p\u003e\u003cp\u003eSeparating these two independent biological processes\u0026rsquo; contributions to wood density is useful for species with higher extractive content when investigating wood quality (Hillis, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e1978\u003c/span\u003e; Lehnebach, Bossu et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Cell wall density was assessed for mapping pulp properties (Ona, Sonoda et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e1997\u003c/span\u003e; Ona, Sonoda et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e1998\u003c/span\u003e) or extractive content when investigating natural durability (Nelson and Heather, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e1972\u003c/span\u003e). Regarding typical species-specific density patterns, this was either achieved by removing extractives by solvent extraction (Nelson and Heather, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e1972\u003c/span\u003e; Wilkins and Horne, \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e1991\u003c/span\u003e; Ona, Sonoda et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e1997\u003c/span\u003e; Ona, Sonoda et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e1998\u003c/span\u003e) or focusing on young trees where heartwood formation had not started (Gon\u0026ccedil;alves, Lorensani et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). While the former is labour intensive, the latter cannot be used for older, heartwood-containing trees.\u003c/p\u003e\u003cp\u003eAs the contribution of extractives is the difference of sapwood and heartwood density, it should, however, be possible to deduce the individual contributions of cell walls and heartwood extractives from density data. This will require local density measurements of sapwood and heartwood on all positions across the stems. These can be obtained if a wide range of tree sizes/ages is sampled for wood density and the wood type is recorded. Such a sample set became available in the course of a biomass study of \u003cem\u003eEucalyptus bosistoana\u003c/em\u003e F.Muell. and \u003cem\u003eEucalyptus globoidea\u003c/em\u003e Blakely. The objective of this study was to demonstrate that typical specie-specific patterns for cell walls and extractive content can be obtained without labour intensive solvent extraction by statistical modelling of local heartwood and sapwood density data from trees spanning a wide age/size range.\u003c/p\u003e\u003cp\u003eWithin stem patterns of heartwood extractives have been documented (Sherrard and Kurth, \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e1933\u003c/span\u003e) and have been described to typically increase from the pith to the heartwood-sapwood boundary and being more abundant further up the stem (Hillis, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e1987\u003c/span\u003e). Radial gradients in heartwood extractives have also been found in branches (Terrasse, Brancheriau et al., \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Heartwood extractives are associated with decay resistance (Hawley, Fleck et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1924\u003c/span\u003e) and durability standards regard inner heartwood as less durable than outer heartwood from old-growth trees (AS5604, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2005\u003c/span\u003e). It appears that these typical specie-specific heartwood extractive content patterns have not been quantitatively modelled.\u003c/p\u003e\u003cp\u003e\u003cem\u003eEucalyptus globoidea\u003c/em\u003e and \u003cem\u003eE. bosistoana\u003c/em\u003e are emerging plantation species with fast-growth (Boczniewicz, Mason et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Their dens and ground-durable heartwood (Poynton, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1979\u003c/span\u003e; Poynton, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1979\u003c/span\u003e; Bootle, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) is suited for structural (Guo and Altaner, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), out-door (Millen, Altaner et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) and biomass products. Extractive contents of up to 15% were reported for \u003cem\u003eE. globoidea\u003c/em\u003e and \u003cem\u003eE. bosistoana\u003c/em\u003e in their heartwood (Li and Altaner, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Considering their applications, cell wall, extractive and total density are relevant properties. However, little is known about the wood density variations of these species.\u003c/p\u003e"},{"header":"2. Material and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Material\u003c/h2\u003e\u003cp\u003eStem discs of \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e trees were obtained during biomass and taper studies of the species. A detailed description of the sites, trees and field sampling procedures is available elsewhere (Boczniewicz, Mason et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Mason, Millen et al., under review). This study was based on stem discs from 74 \u003cem\u003eE. bosistoana\u003c/em\u003e originating from eight sites felled when 2- to 20-years-old, and 63 \u003cem\u003eE. globoidea\u003c/em\u003e trees originating from five sites felled when 7- to 29-years-old (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Stem discs were cut at variable height depending on taper increments (Boczniewicz, Mason et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) and oven-dried. Heartwood was highlighted by applying methyl orange pH indicator.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSites information and summary statistics of wood density data for \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e. Different letters indicate Tukey HSD significance (P\u0026thinsp;=\u0026thinsp;0.01) between wood types in each site.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003e\u003cem\u003eE. bosistoana\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSites\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003eCoordinates\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNumber of trees\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eTree age (years)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eWood type\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003eNumber of blocks\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003eMean wood density (sd) (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e3\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eCravens\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;26\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;56\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e126\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e880.4 (61.0)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e952.2 (48.2)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e132\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e945.0 (51.8)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eDillon\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;66\u0026prime;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;67\u0026prime;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e837.1 (41.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eFlemming\u003c/p\u003e\u003cp\u003e\u003cem\u003e43\u0026deg;11\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e172\u0026deg;39\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e139\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e849.7 (54.0)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e940.2 (46.0)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e898.0 (53.5)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eHoldaway\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;39\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;18\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e757.6 (118.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eLawsons\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;43\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e174\u0026deg;02\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e166\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e888.2 (47.8)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e985.3 (58.6)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e957.4 (48.9)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eMacBeth\u003c/p\u003e\u003cp\u003e\u003cem\u003e42\u0026deg;47\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;11\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e893.6 (52.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003ePukaka\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;24\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e174\u0026deg;00\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e157\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e895.1 (58.9)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e136\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e971.2 (44.7)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e182\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e945.4 (45.1)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eWaikakaho\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;25\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;54\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e827.2 (57.1)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e910.9 (69.3)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e884.5 (54.6)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e2 to 20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e731\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e868.0 (65.9)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e339\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e951.1 (58.5)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e582\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e931.3 (56.6)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003eE. globoidea\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSites\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003eCoordinates\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003eNumber of trees\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eTree age (years)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eWood type\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003eNumber of blocks\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eAvery\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;46\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e174\u0026deg;08\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e639.2 (48.5)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e831.2 (43.9)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e727.6 (78.0)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eEttrick\u003c/p\u003e\u003cp\u003e\u003cem\u003e43\u0026deg;47\u0026rsquo;32.0\u0026rsquo;\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e172\u0026deg;50\u0026rsquo;20.8\u0026rsquo;\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e322\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e618.6 (73.3)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1005\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e664.5 (87.4)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e262\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e696.0 (76.4)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eJNL\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;02\u0026rsquo;42.7\u0026rsquo;\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e175\u0026deg;52\u0026rsquo;37.2\u0026rsquo;\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e106\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e568.8 (61.2)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e701.3 (46.6)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e644.7 (41.2)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eMacBeth\u003c/p\u003e\u003cp\u003e\u003cem\u003e42\u0026deg;47\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e173\u0026deg;11\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e118\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e610.5 (62.1)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e771.7 (72.9)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e118\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e685.4 (65.3)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003ePukaka\u003c/p\u003e\u003cp\u003e\u003cem\u003e41\u0026deg;24\u0026rsquo;S\u003c/em\u003e\u003c/p\u003e\u003cp\u003e\u003cem\u003e174\u0026deg;00\u0026rsquo;E\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e234\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e645.5 (51.4)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e330\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e712.6 (59.0)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e220\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e688.1 (60.6)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e7 to 29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e834\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e620.0 (67.3)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHW\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1397\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e679.9 (85.3)\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMix\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e626\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e696.0 (71.6)\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. Density\u003c/h2\u003e\u003cp\u003eA 2.5 cm wide full diameter strip including the pith was split from each of the 3\u0026ndash;5 cm thick stem disc. These strips were further split into wood blocks, 2.5 x 2.5 cm in cross-section, starting with a block centred over the pith. Wood blocks were dried at 103\u0026deg;C before each block was weighed and the heartwood percentage of each block was estimated to the nearest 10%. The volume of each block was then determined by immersion weighing in water. Dry density was calculated as the ratio of dry mass and dry volume.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3. Data analysis\u003c/h2\u003e\u003cp\u003eData was analysed with the R software (R Core Team, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). For analysing the site effect on heartwood density without confounding of tree age, only heartwood samples centred at the pith within the first 0.5 m stem height were considered. Tukey HSD tests were used to test significance (p\u0026thinsp;=\u0026thinsp;0.01) of differences between groups. Linear mixed effect models were calculated with the lmer function of the lme4 package (Bates, M\u0026auml;chler et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). The model for dry wood density of each species considered distance from the pith (cm), disc height (m) and heartwood (%) as well as their two-way interactions, and site as fixed effects. Potential correlations in observations taken from the same tree were accounted for by including tree as a random effect.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003eThe mean dry heartwood density of the \u003cem\u003eE. bosistoana\u003c/em\u003e tress in this study was 951 kg m\u003csup\u003e-3\u003c/sup\u003e (Table 1). Considering the published tangential movement of 0.42% per % change in moisture content (MC) (AS1720.2, 2006) and a radial to tangential movement ratio of 1 : 2, this equated to approximately 1000 kg m\u003csup\u003e-3\u003c/sup\u003e at 12% MC. The mean dry sapwood density of 868 kg m\u003csup\u003e-3\u003c/sup\u003e (Table 1) equated to ~900 kg m\u003csup\u003e-3\u003c/sup\u003e at 12% MC.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDry density of the \u003cem\u003eE. globoidea\u003c/em\u003e heartwood was 680 kg m\u003csup\u003e-3\u003c/sup\u003e (Table 1) or approximately 710 kg m\u003csup\u003e-3\u003c/sup\u003e at 12% (MC) considering 0.36% per % MC change (AS1720.2, 2006). The average sapwood dry density of the \u003cem\u003eE. globoidea\u003c/em\u003e trees was 620 kg m\u003csup\u003e-3\u003c/sup\u003e (Table 1), equating to approximately 640 kg m\u003csup\u003e-3\u003c/sup\u003e at 12% MC.\u003c/p\u003e\n\u003cp\u003e3.1.\u0026nbsp; Site effect\u003c/p\u003e\n\u003cp\u003eSite means of heartwood dry density at the centre base of the stem, that is within 13 mm of the pith and below 0.5 m stem height, ranged between 902 and 1006 kg m\u003csup\u003e-3\u003c/sup\u003e for \u003cem\u003eE. bosistoana\u003c/em\u003e and 689 and 843 kg m\u003csup\u003e-3\u003c/sup\u003e for \u003cem\u003eE. globoidea\u003c/em\u003e, respectively (Fig. 1). The difference among sites was statistically significant (P = 0.01) for both species.\u003c/p\u003e\n\u003cp\u003eThe same analysis for sapwood suffered from limited observations at a given stem position across sites, giving low confidence in the results.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.2.\u0026nbsp; Radial and axial density patterns\u003c/p\u003e\n\u003cp\u003eThe data allowed to investigate the effects of height, distance from the pith, heartwood extractives and site on dry wood density for \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e. All effects including the two-way interactions between stem height, distance from the pith and extractive content were significant (Table 2). The models revealed complex typical specie-specific density patterns within the stem. Individual contributions of cell walls and extractives differed between the two species.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor \u003cem\u003eE. bosistoana\u003c/em\u003e the sapwood density, i.e. the contribution of the cell walls, had negative coefficients for stem height and distance from the pith and a positive interaction term between the two (Table 2), resulting in a saddle like pattern with lower density at the top of the stem and the outer stem base (Fig. 2). The contribution of heartwood extractives increased with distance from the centre base of the stem, i.e. terms for stem height, distance to the pith and their interaction were positive (Table 2). The resulting heartwood density pattern within the stems, i.e. the combination of cell walls and heartwood extractives, was complex with the radial density gradient dependent on the height (Fig. 2).\u003c/p\u003e\n\u003cp\u003eThe within stem wood density patterns of \u003cem\u003eE. globoidea\u003c/em\u003e differed from those of \u003cem\u003eE. bosistoana\u003c/em\u003e (Fig. 3). Sapwood density, i.e. the contribution of cell walls, increased with distance from the centre base of the stem, i.e. had positive terms for height, distance from the pith as well as their interaction (Table 2). Also, in contrast to \u003cem\u003eE. bosistoana\u003c/em\u003e, heartwood extractives decreased with stem height and distance from the pith, ie heartwood related terms were negative (Table 2).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor both species, the significance of site on wood density described in section 3.1 was also reflected in the significance of site terms in this model (Table 2).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Fixed effect estimates on within stem dry density of \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e. Significance levels: * p \u0026lt; 0.05; ** p \u0026lt; 0.01 and *** p \u0026lt; 0.001.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFixed effects\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eE. bosistoana\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eE. globoidea\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eIntercept (kg m\u003csup\u003e-3\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e931***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e648***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eRadius (kg m\u003csup\u003e-3\u003c/sup\u003e cm\u003csup\u003e-1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e-4.43***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e7.17***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eDisk height (kg m\u003csup\u003e-3\u003c/sup\u003e m\u003csup\u003e-1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e-5.40***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e3.97***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eInteraction of radius and disk height (kg m\u003csup\u003e-3\u003c/sup\u003e cm\u003csup\u003e-2\u003c/sup\u003e m\u003csup\u003e-1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e0.888***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e0.244***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eHeartwood (kg m\u003csup\u003e-3\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e37***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e118***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eInteraction of heartwood and radius (kg m\u003csup\u003e-3\u003c/sup\u003e cm\u003csup\u003e-1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e5.43***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e-2.33***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eInteraction of heartwood and disk height (kg m\u003csup\u003e-3\u003c/sup\u003e m\u003csup\u003e-1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e3.84***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e-1.68***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 170px;\"\u003e\n \u003cp\u003eSite (kg m\u003csup\u003e-3\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eMacBeth\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ePukaka\u003c/p\u003e\n \u003cp\u003eWaikakaho\u003c/p\u003e\n \u003cp\u003eDillon\u003c/p\u003e\n \u003cp\u003eFlemming\u003c/p\u003e\n \u003cp\u003eHoldaway\u003c/p\u003e\n \u003cp\u003eLawsons\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e-23.6\u003c/p\u003e\n \u003cp\u003e6.6\u003c/p\u003e\n \u003cp\u003e-52.0**\u003c/p\u003e\n \u003cp\u003e-88.1***\u003c/p\u003e\n \u003cp\u003e-52.4***\u003c/p\u003e\n \u003cp\u003e-166***\u003c/p\u003e\n \u003cp\u003e-7.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003eMacBeth\u003c/p\u003e\n \u003cp\u003ePukaka\u003c/p\u003e\n \u003cp\u003eEttrick\u003c/p\u003e\n \u003cp\u003eJNL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003e-47.3*\u003c/p\u003e\n \u003cp\u003e-69.4**\u003c/p\u003e\n \u003cp\u003e-125***\u003c/p\u003e\n \u003cp\u003e-101***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eDensities at 12% MC have been published for \u003cem\u003eE. bosistoana\u003c/em\u003e heartwood from old-growth Australian forests (1100 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (AS1720.2, \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) and heartwood from 42-year-old trees grown in Urugay (942 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (Mantero, O\u0026rsquo;Neill et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). The less than 20-year-old NZ-grown \u003cem\u003eE. bosistoana\u003c/em\u003e tress in this study were with a heartwood density of ~\u0026thinsp;1000 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e (section 3) denser than the timber grown in Urugay. The mean sapwood density (~\u0026thinsp;900 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e at 12% MC) was higher than the reported 816 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e for 2-year-old seedings of this species (Davies, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2019\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eDensity of the \u003cem\u003eE. globoidea\u003c/em\u003e heartwood was with 710 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e at 12% MC considerably lower than the 850 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e reported for heartwood sourced from old-growth Australian forests (AS1720.2 \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). It, however, fell in the reported range (640 to 830 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) for the species by Ilic (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2002\u003c/span\u003e) and NZ-grown plantation trees aged 30-year-old (690 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (Guo and Altaner, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), 28-year-old (720 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (Scown, Lim et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), or 25-year-old (655 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (Jones, McConnochie et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Sapwood density of approximately 640 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e at 12% MC, was similar to that reported for tops of 7-year-old trees (600\u0026ndash;630 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) but was lower than that of 2-year-old coppice (660 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e) (Iyiola, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). It should be noted that the differences discussed above are a combination of both, site and tree age.\u003c/p\u003e\u003cp\u003eIn average. heartwood for both species was denser than its sapwood (Tabel 1). The 83 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e and 60 kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e for \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e, respectively. Ignoring radial or axial gradients described below, this suggested an extractive content of ~\u0026thinsp;9% in the heartwood. This was plausible, as the ethanol soluble extractive fraction made up ~\u0026thinsp;5% (ranging up to 14%) of the heartwood in young 7-year-old \u003cem\u003eE. bosistoana\u003c/em\u003e and 5- to 80-year-old \u003cem\u003eE. globoidea\u003c/em\u003e trees (Li, Apiolaza et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e4.1. Site effect\u003c/h2\u003e\u003cp\u003eSite and tree age was confounded in this data set. However, in contrast to previous studies reporting whole tree density (McKinley, Shelbourne et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2000\u003c/span\u003e), by comparing wood density at a fixed position in the stem, it was possible to remove the confounding age effect and test for site effects. The site effect on heartwood density at the centre base of the stem was significant in this study (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Site effects on wood density are well known for other tree species (Raymond and Muneri, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2001\u003c/span\u003e; Kimberley, Cown et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Hein, Chaix et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Vega, Hamilton et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), but had not been confirmed for \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e.\u003c/p\u003e\u003cp\u003eIt was not possible to differentiate the contributions of cell walls and heartwood extractives, as the study lacked sapwood data for this within stem location. It is likely that both factors are site dependent. Site difference in heartwood extractive contents for replicated breeding trials of \u003cem\u003eE. bosistoana\u003c/em\u003e have been detected (Li, Apiolaza et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) and are relevant for spices grown for their durable heartwood. The available data did not allow to investigate environmental variables influencing wood density in these species.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e4.2. Radial and axial density patterns within stems\u003c/h2\u003e\u003cp\u003eAxial and radial gradients of wood density have been reported for eucalypts (Hillis, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e1978\u003c/span\u003e). Consistent with this study, Frederick, Madgwick et al. (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e1982\u003c/span\u003e) reported distinct radial profiles at different heights of the stem for heartwood of 17-year-old \u003cem\u003eE. regnans\u003c/em\u003e F.Muell. trees but contributions of cell walls and heartwood extractives were not separated. Complex within stem sapwood density patterns have also been recorded for young \u003cem\u003eEucalyptus grandis\u003c/em\u003e W.Hill ex Maiden and its hybrid with \u003cem\u003eEucalyptus urophylla\u003c/em\u003e S.T.Blake (Wilkins and Horne, \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e1991\u003c/span\u003e; Hein, Chaix et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). But these studies did not quantified the effects of stem height and distance from the pith. Typical specie-specific radial density patters in heartwood of some eucalypt species have been quantified as relevant wood property for rotary peeled veneer (McGavin, Bailleres et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Vega, Hamilton et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Neiter study quantified the effect of heartwood extractives.\u003c/p\u003e\u003cp\u003eIt is worth mentioning that the linear nature of the used mixed effect model in this study does not allow extrapolation to larger trees, as density gradients approach a maximum asymptote in mature trees. The developed models are applicable for short-rotation plantations, but more complex function such as the sigmoidal functions used by McGavin, Bailleres et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) might be needed for larger trees.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e4.3. Within stem heartwood extractive patterns\u003c/h2\u003e\u003cp\u003eThe with distance from the centre base of the stem observed increasing heartwood extractive content in \u003cem\u003eE. bosistoana\u003c/em\u003e matched the commonly described pattern for a range of tree species (Hillis, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e1987\u003c/span\u003e). Higher amounts of extractives were reported for outer than inner heartwood of \u003cem\u003eEucalyptus marginata\u003c/em\u003e Sm. (Hillis, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1956\u003c/span\u003e), or \u003cem\u003eE. grandis\u003c/em\u003e (Bamber, Floyd et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e1969\u003c/span\u003e). It appears that no decreasing radial or axial gradients in heartwood extractives have been reported in literature and in this sense \u003cem\u003eE. globoidea\u003c/em\u003e seems to be unique. But the polyphenol content in heartwood of \u003cem\u003eE. grandis\u003c/em\u003e was found to be not affected by sampling height in the 5 innermost annual rings (Bamber, Floyd et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e1969\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe radially decreasing resin content in softwoods (Uprichard and Lloyd, \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e1980\u003c/span\u003e) is unrelated to heartwood extractives as softwood resins are synthesised in epithelial cells able to flow through the stem in the resin canal network (Govina, Apiolaza et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) and not fixed in space like heartwood extractives after deposition in the cell walls when sapwood transforms into heartwood in the transition zone.\u003c/p\u003e\u003cp\u003eSite was also reported to affect the amount of heartwood extractives of \u003cem\u003eEucalyptus globulus\u003c/em\u003e Labill. (Pereira, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e1988\u003c/span\u003e; Morais and Pereira, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2012\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eThe study demonstrated the complexity of within-stem wood density patterns in \u003cem\u003eE. bosistoana\u003c/em\u003e and \u003cem\u003eE. globoidea\u003c/em\u003e. Heartwood extractives significantly influence density variations, with distinct radial and axial gradients differing between species. Site effects further shape these patterns. Contributions of cell walls and heartwood extractives and can be deduced from sapwood and heartwood density without the need for chemical extraction, if both data are available across the stem.\u003c/p\u003e\u003cp\u003eWood properties related to cell walls such as strength, and those related to heartwood extractives such as durability are expected to correlate better with the individual density contributions rather than the commonly reported heartwood patterns. If wood density maps are used to predict wood properties for species featuring high extractive contents, the individual contributions should be considered.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author has no financial interests to disclose. Clemens Altaner is a director of New Zealand Dryland Forests IP Limited.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eC.A. conceived the study, analyzed the data and wrote the manuscript.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eI thank Georgia Kennedy, Christophe Robert, Monika Sharma, Maxime Ponsoda, Kura Ngahere | School of Forestry, Te Whare Wānanga O Waitaha | University of Canterbury, for measuring density and heartwood, and Luis Apiolaza, Kura Ngahere | School of Forestry, Te Whare Wānanga O Waitaha | University of Canterbury, for statistical advice.\u003c/p\u003e\n\u003ch2\u003eData Availability\u003c/h2\u003e\n\u003cp\u003eData is provided within the manuscript or supplementary information files.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAS1720.2, 2006. Timber structuresPart 2: Timber properties, Australian Standard,pp. 20.\u003c/li\u003e\n\u003cli\u003eAS5604, 2005. Timber - Natural durability ratings, Australian Standard.\u003c/li\u003e\n\u003cli\u003eBamber R.K., A.G. Floyd, et al., 1969. Wood properties of flooded gum. Austral. For. 33(1): 3-12.\u003c/li\u003e\n\u003cli\u003eBates D., M. M\u0026auml;chler, et al., 2015. Fitting Linear Mixed-Effects Models Using lme4. Journal of Statistical Software, 67(1): 1-48.\u003c/li\u003e\n\u003cli\u003eBoczniewicz D., E.G. Mason, et al., 2022. Developing fully compatible taper and volume equations for all stem components of \u003cem\u003eEucalyptus globoidea\u003c/em\u003e Blakely trees in New Zealand. New Zealand Journal of Forestry Science 52(6).\u003c/li\u003e\n\u003cli\u003eBootle K.R., 2005. Wood in Australia. Types, properties, and uses, McGraw-Hill Australia, 452 p.\u003c/li\u003e\n\u003cli\u003eDavies N.T., 2019. High throughput breeding for wood quality improvement, University of Canterbury, Christchurch, New Zealand,pp. 191.\u003c/li\u003e\n\u003cli\u003eFengel D., 1991. Chemical studies on the wood of quebracho colorado (schinopsis balansae engl.) part 1. composition of sapwood and heartwood. Holzforschung 45(4): 259-263.\u003c/li\u003e\n\u003cli\u003eFrederick D.J., H.A.I. Madgwick, et al., 1982. Wood basic density and moisture content of young \u003cem\u003eEucalyptus regnans\u003c/em\u003e grown in New Zealand New Zealand Journal of Forestry Science 12(3): 494-500.\u003c/li\u003e\n\u003cli\u003eGon\u0026ccedil;alves R., R.G.M. Lorensani, et al., 2019. Evolution of acoustical, geometrical, physical, and mechanical parameters from seedling to cutting age in Eucalyptus clones used in the pulp and paper industries in Brazil. Forest Products Journal 69(1): 5-16.\u003c/li\u003e\n\u003cli\u003eGovina J.K., L.A. Apiolaza, et al., 2021. Variation and genetic parameters of axial resin canal features in clones and families of \u003cem\u003ePinus radiata\u003c/em\u003e. New For. 52(1): 167-176.\u003c/li\u003e\n\u003cli\u003eGuo F. and C.M. Altaner, 2018. Properties of rotary peeled veneer and laminated veneer lumber (LVL) from New Zealand grown Eucalyptus globoidea. New Zealand Journal of Forestry Science 48(3): 10.\u003c/li\u003e\n\u003cli\u003eHawley L.F., L.C. Fleck, et al., 1924. The relation between durability and chemical composition in wood. Ind Eng Chem 16: 699-700.\u003c/li\u003e\n\u003cli\u003eHein P.R.G., G. Chaix, et al., 2016. Spatial variation of wood density, stiffness and microfibril angle along Eucalyptus trunks grown under contrasting growth conditions. Trees-Struct. Funct. 30(3): 871-882.\u003c/li\u003e\n\u003cli\u003eHillis W., 1956. Leucoanthocyanins as the possible precursors of extractives in woody tissues. Australian Journal of Biological Sciences 9(2): 263-280.\u003c/li\u003e\n\u003cli\u003eHillis W.E., 1978. Wood quality and utilization. In: Hillis W. E. and Brown A. G. (Eds.), Eucalypts for wood production, CSIRO, Adelaide, Australia,pp. 259-289.\u003c/li\u003e\n\u003cli\u003eHillis W.E., 1987. Heartwood and tree exudates, Springer Verlag, Berlin, 268 p.\u003c/li\u003e\n\u003cli\u003eIlic J., 2002. Woods of Eucalyptus - Part 2 - Distinguishing species from the stringybark group (E-baxteri, E-globoidea, E-muelleriana, E-macrorhyncha, E-consideniana and E-sieberi). Iawa J. 23(3): 305-318.\u003c/li\u003e\n\u003cli\u003eIyiola E.A., 2021. Wood quality of durable eucalypts.\u003c/li\u003e\n\u003cli\u003eJones T.G., R.M. McConnochie, et al., 2010. Sawing and grade recovery of 25-year-old Eucalyptus fastigata, E. globoidea, E. muelleriana and E. pilularis. New Zealand Journal of Forestry Science 40: 19-31.\u003c/li\u003e\n\u003cli\u003eKellogg R.M. and F.F. Wangaard, 1969. Variation in The Cell-Wall Density of Wood Wood and Fiber Science (3): 180-204.\u003c/li\u003e\n\u003cli\u003eKimberley M., D. Cown, et al., 2015. Modelling variation in wood density within and among trees in stands of New Zealand-grown radiata pine. New Zealand Journal of Forestry Science 45(1): 22.\u003c/li\u003e\n\u003cli\u003eLehnebach R., J. Bossu, et al., 2019. Wood Density Variations of Legume Trees in French Guiana along the Shade Tolerance Continuum: Heartwood Effects on Radial Patterns and Gradients. Forests 10(2): 80.\u003c/li\u003e\n\u003cli\u003eLi Y. and C. Altaner, 2019. Calibration of near infrared spectroscopy (NIRS) data of three Eucalyptus species with extractive contents determined by ASE extraction for rapid identification of species and high extractive contentsHolzforschung,pp. 537.\u003c/li\u003e\n\u003cli\u003eLi Y., L.A. Apiolaza, et al., 2018. Genetic variation in heartwood properties and growth traits of Eucalyptus bosistoana. Eur. J. For. Res. 137(4): 565-572.\u003c/li\u003e\n\u003cli\u003eMantero C., H. O\u0026rsquo;Neill, et al., 2014. Propiedades f\u0026iacute;sicas y mec\u0026aacute;nicas de la madera de una poblaci\u0026oacute;n de \u003cem\u003eEucalyptus bosistoana\u003c/em\u003e F. Muell. cultivada en Uruguay. Agrociencia Uruguay 18(1): 65-74.\u003c/li\u003e\n\u003cli\u003eMason E.G., P. Millen, et al., under review. Modelling above-ground biomass of \u003cem\u003eEucalyptus bosistoana\u003c/em\u003e and \u003cem\u003eEucalyptus globoidea\u003c/em\u003e. New Zealand Journal of Forest Science.\u003c/li\u003e\n\u003cli\u003eMcGavin R.L., H. Bailleres, et al., 2015. Stiffness and Density Analysis of Rotary Veneer Recovered from Six Species of Australian Plantation Hardwoods. Bioresources 10(4): 6395-6416.\u003c/li\u003e\n\u003cli\u003eMcKinley R.B., C.J.A. Shelbourne, et al., 2000. Variation in whole-tree basic wood density for a range of plantation species grown in New Zealand. NZ Journal of Forestry Science 30(3): 436-446.\u003c/li\u003e\n\u003cli\u003eMillen P., C. Altaner, et al., 2018. Naturally durable timber posts performing well. New Zealand Tree Grower 39(1): 24-26.\u003c/li\u003e\n\u003cli\u003eMorais M.C. and H. Pereira, 2012. Variation of extractives content in heartwood and sapwood of Eucalyptus globulus trees. Wood Science and Technology 46(4): 709-719.\u003c/li\u003e\n\u003cli\u003eNelson N.D. and W.A. Heather, 1972. Wood color, basic density, and decay resistance in heartwood of fast-grown\u003cem\u003e Eucalyptus grandis\u003c/em\u003e Hill ex Maiden. 26(2): 54-60.\u003c/li\u003e\n\u003cli\u003eOna T., T. Sonoda, et al., 1997. Relationship between various extracted basic densities and wood chemical components in Eucalyptus camaldulensis. Wood Science and Technology 31(3): 205-216.\u003c/li\u003e\n\u003cli\u003eOna T., T. Sonoda, et al., 1998. Relations between various extracted basic densities and wood chemical components in Eucalyptus globulus. Journal of Wood Science 44(3): 165-168.\u003c/li\u003e\n\u003cli\u003ePereira H., 1988. Variability in the Chemical-Composition of Plantation Eucalypts (Eucalyptus-Globulus Labill). Wood and Fiber Science 20(1): 82-90.\u003c/li\u003e\n\u003cli\u003ePoynton R.J., 1979. \u003cem\u003eEucalyptus bosistoana\u003c/em\u003e F. Mueller. In: Poynton R. J. (Ed.) Tree Planting in Southern Africa: The eucalypts, Department of Forestry, South Africa,pp. 101-106.\u003c/li\u003e\n\u003cli\u003ePoynton R.J., 1979. \u003cem\u003eEucalyptus globoidea\u003c/em\u003e Blakely. In: Poynton R. J. (Ed.) Tree Planting in Southern Africa: The eucalypts, Department of Forestry, South Africa,pp. 316-324.\u003c/li\u003e\n\u003cli\u003eR Core Team, 2022. R: A language and environment for statistical computing, R Foundation for Statistical Computing, Vienna, Austria.\u003c/li\u003e\n\u003cli\u003eRaymond C.A. and A. Muneri, 2001. Nondestructive sampling of Eucalyptus globulus and E. nitens for wood properties. I. Basic density. Wood Science and Technology 35(1-2): 27-39.\u003c/li\u003e\n\u003cli\u003eSchimleck L., J. Dahlen, et al., 2025. Maps depicting the within-tree wood property variation of some North American conifers: a review. Canadian Journal of Forest Research 55: 1-14.\u003c/li\u003e\n\u003cli\u003eScown H., H. Lim, et al., 2023. Machinability of plantation-grown Eucalyptus globoidea timber. Wood Material Science \u0026amp; Engineering: 1-6.\u003c/li\u003e\n\u003cli\u003eSherrard E.C. and E.F. Kurth, 1933. Distribution of extractive in redwood - Its relation to durability. Ind Eng Chem 25: 300-302.\u003c/li\u003e\n\u003cli\u003eSkolmen R.G., 1972. Specific gravity variation in robusta eucalyptus grown in Hawaii. In: Station P. S. F. R. E. (Ed.) Res. Paper PSW-RP-78, Forest Service, U.S. Department of Agriculture, Berkeley, CA,pp. 7.\u003c/li\u003e\n\u003cli\u003eTaylor A.M., B.L. Gartner, et al., 2002. Heartwood formation and natural durability - a review. Wood and Fiber Science 34(4): 587-611.\u003c/li\u003e\n\u003cli\u003eTelmo C. and J. Lousada, 2011. The explained variation by lignin and extractive contents on higher heating value of wood. Biomass and Bioenergy 35(5): 1663-1667.\u003c/li\u003e\n\u003cli\u003eTerrasse F., L. Brancheriau, et al., 2021. Density, extractives and decay resistance variabilities within branch wood from four agroforestry hardwood species. iForest - Biogeosciences and Forestry 14(3): 212-220.\u003c/li\u003e\n\u003cli\u003eUprichard J.M. and J.A. Lloyd, 1980. Influence of tree age on the chemical composition of radiata pine. New Zealand Journal of Forestry Science 10(3): 551-557.\u003c/li\u003e\n\u003cli\u003eVega M., M. Hamilton, et al., 2020. Radial variation in modulus of elasticity, microfibril angle and wood density of veneer logs from plantation-grown Eucalyptus nitens. Ann. For. Sci. 77(3): 65.\u003c/li\u003e\n\u003cli\u003eWilkins A.P. and R. Horne, 1991. Wood-density variation of young plantation-grown \u003cem\u003eEucalyptus grandis\u003c/em\u003e in response to silvicultural treatments. For. Ecol. Manage. 40(1-2): 39-50.\u003c/li\u003e\n\u003cli\u003eZanne A.E., G. Lopez-Gonzalez, et al., 2009. Data from: Towards a worldwide wood economics spectrum. In: Dryad (Ed.).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Coast grey box, Eucalyptus bosistoana F.Muell., Eucalyptus globoidea Blakely, sapwood, white stringybark","lastPublishedDoi":"10.21203/rs.3.rs-6844932/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6844932/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eContext\u003c/strong\u003e\u003c/em\u003e:\u003c/p\u003e\n\u003cp\u003eWood density varies within stems from pith to bark and base to top. Wood density is the combination of cell walls and extractives, each factor controlling different wood properties. Understanding the distribution of heartwood extractives is critical for species grown for their heartwood.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eAims\u003c/strong\u003e\u003c/em\u003e:\u003c/p\u003e\n\u003cp\u003eHeartwood compounds are resource intensive to quantify by chemical extraction and have been rarely considered in studies of within stem wood density patterns. The objective was to disentangle the contributions of cell walls and extractives to within stem density patterns without the need for extraction.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBy sampling \u003cem\u003eEucalyptus bosistoana\u003c/em\u003e F.Muell. and \u003cem\u003eEucalyptus globoidea\u003c/em\u003e Blakely trees across a wide age-range, wood density of heartwood and sapwood was measured for all within-stem positions. Statistical modelling allowed to quantify the contributions of cell walls and heartwood extractives to specie-specific within-stem density patterns.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/em\u003e:\u003c/p\u003e\n\u003cp\u003eHeartwood extractives had a significant effect on wood density for the two species. The within-stem patterns differed between species and were complex.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eStrategically sampling wood density for a wide age-range of trees allows to deduce the complex specie-specific within stem patterns of heartwood extractives and cell walls, without the laborious task of wood extraction. This improves our understanding of wood quality.\u003c/p\u003e","manuscriptTitle":"The influence of heartwood extractives on wood density patterns in tree stems","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-25 06:39:03","doi":"10.21203/rs.3.rs-6844932/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b80db3da-daaf-4186-a3c9-3b12f992b9c6","owner":[],"postedDate":"July 25th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-27T13:38:41+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-25 06:39:03","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6844932","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6844932","identity":"rs-6844932","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}