Advertisement

The effect of thinning on mechanical properties of Douglas fir, Norway spruce, and Sitka spruce

  • Luka Krajnc
  • Niall Farrelly
  • Annette M. Harte
Research Paper

Abstract

Key message

Thinning affects negatively the quality of sawn timber of Douglas fir, Norway spruce, and Sitka spruce. The effect was confirmed in structural-sized boards and small clear samples, and on standing trees using longitudinal velocity. The loss of quality across the three species due to thinning rarely exceeds 20% and is in most cases smaller than 5%.

Context

The relationship between silvicultural management and the quality of timber produced is not entirely elucidated.

Aims

The effects of thinning on structural grade-determining properties of wood (elastic modulus, bending strength and density) were studied on Douglas fir (Pseudotsuga menziesii (Mirb.) Franco), Norway spruce (Picea abies (L.) H. Karst), and Sitka spruce (Picea sitchensis (Bong.) Carr)).

Methods

Acoustic velocity was measured in a total of 487 trees and their crown social status was recorded. Sixty trees were selected and cut into structural-sized boards (N = 1343). The amount of knots in each board was quantified using the grading machine GoldenEye702. All boards were destructively tested in four-point bending, after which a small clear specimen was cut from each board and again tested in bending (N = 1303). Specific stiffness and specific strength were used to estimate the size of the effect accounting for differing influence of thinning across the before-mentioned properties.

Results

Thinning reduces all three properties with the likelihood and magnitude of the effect varying between species. The loss of quality due to thinning rarely exceeds 20% and is in most cases smaller than 5%. The effect of thinning and its size were also confirmed on the full sample of trees by using longitudinal velocity.

Conclusion

The results give a clearer idea of what the trade-offs are between timber quality and silvicultural management.

Keywords

Thinning Wood quality Softwoods Bayesian analysis 

Notes

Acknowledgements

The authors would like to thank Coillte and the Irish Forestry Unit Trust for enabling access to the forest stands and providing the testing material. The use of GoldenEye-702 machine was kindly provided by the Murray Timber Group while Martin Bacher from MiCROTEC helped with the scanning of the boards.

Funding

The first author was supported in undertaking this work by a Teagasc Walsh Fellowship. This work was also supported by grant aid from the Forest Sector Development Division of the Department of Agriculture, Food and the Marine, Ireland.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

References

  1. Amarasekara H, Denne MP (2002) Effects of crown size on wood characteristics of Corsican pine in relation to definitions of juvenile wood, crown formed wood and core wood. Forestry 75:51–61.  https://doi.org/10.1093/forestry/75.1.51 CrossRefGoogle Scholar
  2. Aslezaeim N (2016) Effect of cultural intensity and planting density on wood properties of loblolly pine (Pinus taeda L.). Ph.D., Mississippi State University, United States – MississippiGoogle Scholar
  3. Assmann E (1970) The principles of forest yield study: studies in the organic production, structure, increment, and yield of forest stands. Pergamon PressGoogle Scholar
  4. Auty D, Weiskittel AR, Achim A, Moore JR, Gardiner BA (2012) Influence of early respacing on Sitka spruce branch structure. Ann For Sci 69:93–104.  https://doi.org/10.1007/s13595011-0141-8 CrossRefGoogle Scholar
  5. Bérubé-Deschênes A, Franceschini T, Schneider R (2016) Factors affecting plantation grown white spruce (Picea Glauca) acoustic velocity. J For 114:629–637.  https://doi.org/10.5849/jof.15141 CrossRefGoogle Scholar
  6. Brancheriau L, Bailleres H, Guitard D (2002) Comparison between modulus of elasticity values calculated using 3- and 4-point bending tests on wooden samples. Wood Sci Technol 36:367–383.  https://doi.org/10.1007/s00226-002-0147-3 CrossRefGoogle Scholar
  7. Brazier JD (1977) The effect of Forest practices on quality of the harvested crop. Forestry 50:49–66.  https://doi.org/10.1093/forestry/50.1.49 CrossRefGoogle Scholar
  8. British Standards Institution (1957) Methods of testing small clear specimens of timber. British Standards Institution, London oCLC: 958830993Google Scholar
  9. Brüchert F, Becker G, Speck T (2000) The mechanics of Norway spruce [Picea abies (L.) karst]: mechanical properties of standing trees from different thinning regimes. For Ecol Manag 135:45–62.  https://doi.org/10.1016/S0378-1127(00)00297-8 CrossRefGoogle Scholar
  10. Bues CT (1985) Der Einfluß von Bestockungsgrad und Durchforstung auf die Rohdichte von südafrikanischer Pinus radiata (The influence of stand density and thinning on the wood density of South African radiata pine) (In German). Holz Roh Werkst 43:69–73.  https://doi.org/10.1007/BF02607108 CrossRefGoogle Scholar
  11. Bürkner PC (2017) Brms: an R package for Bayesian multilevel models using Stan. J Stat Softw 80:1–28.  https://doi.org/10.18637/jss.v080.i01 CrossRefGoogle Scholar
  12. Cameron AD (2002) Importance of early selective thinning in the development of long-term stand stability and improved log quality: a review. Forestry 75:25–35.  https://doi.org/10.1093/forestry/75.1.25 CrossRefGoogle Scholar
  13. Cameron A, Gardiner B, Ramsay J, Drewett T (2015) Effect of early release from intense competition within high density natural regeneration on the properties of juvenile and mature wood of 40-year-old Sitka spruce (Picea sitchensis (Bong.) Carr.). Ann For Sci 72:99–107.  https://doi.org/10.1007/s13595-014-0402-4 CrossRefGoogle Scholar
  14. Carpenter B, Gelman A, Hoffman MD, Lee D, Goodrich B, Betancourt M, Brubaker M, Guo J, Li P, Riddell A (2017) Stan: a probabilistic programming language. J Stat Softw 76.  https://doi.org/10.18637/jss.v076.i01
  15. Carson SD, Cown DJ, McKinley RB, Moore JR (2014) Effects of site, silviculture and seedlot on wood density and estimated wood stiffness in radiata pine at mid-rotation. N Z J For Sci 44:26–26.  https://doi.org/10.1186/s40490-014-0026-3 CrossRefGoogle Scholar
  16. CEN (2002) EN 13183–1:2002 - Moisture content of a piece of sawn timber - Part 1: Determination of oven dry methodGoogle Scholar
  17. CEN (2010) EN 384:2016 - Structural timber - Determination of characteristic values of mechanical properties and densityGoogle Scholar
  18. CEN (2012) EN 408:2010+A1:2012 - Timber structures - Structural timber and glued laminated timber - Determination of some physical and mechanical propertiesGoogle Scholar
  19. CEN (2016) EN 338:2016 - Structural timber - Strength classesGoogle Scholar
  20. Chen L, Xiang W, Wu H, Lei P, Zhang S, Ouyang S, Deng X, Fang X (2017) Tree growth traits and social status affect the wood density of pioneer species in secondary subtropical forest. Ecol Evol 7:5366–5377.  https://doi.org/10.1002/ece3.3110 CrossRefPubMedPubMedCentralGoogle Scholar
  21. Cown DJ (1973) Comparison of the effects of two thinning regimes on some wood properties of radiata pine. N Z J For Sci 4:12Google Scholar
  22. Cown DJ, McConchie DL (1982) Rotation age and silvicultural effects on wood properties of four stands of Pinus radiata. N Z J For Sci 12:71–85Google Scholar
  23. Deng X, Zhang L, Lei P, Xiang W, Yan W (2014) Variations of wood basic density with tree age and social classes in the axial direction within Pinus massoniana stems in southern China. Ann For Sci 71:505–516.  https://doi.org/10.1007/s13595-013-0356-y CrossRefGoogle Scholar
  24. Dungey HS, Matheson AC, Kain D, Evans R (2006) Genetics of wood stiffness and its component traits in Pinus radiata. Can J For Res 36:1165–1178.  https://doi.org/10.1139/X06-014 CrossRefGoogle Scholar
  25. Eriksson D, Lindberg H, Bergsten U (2006) Influence of silvicultural regime on wood structure characteristics and mechanical properties of clear wood in Pinus sylvestris. Silva Fenn 40:743–762Google Scholar
  26. Evertsen JA, O’Brien D (1985) The effect of thinning and initial spacing on wood quality determining properties in Sitka spruce. In: Gallagher G (ed) The influence of spacing and selectivity in thinning on stand development, operations and economy, forest and wildlife service, Dublin, pp 130–139Google Scholar
  27. Gardiner B, Leban JM, Auty D, Simpson H (2011) Models for predicting wood density of British-grown Sitka spruce. Forestry 84:119–132.  https://doi.org/10.1093/forestry/cpq050 CrossRefGoogle Scholar
  28. Gelman A, Carlin JB, Stern HS, Rubin DB (2004) Bayesian data analysis, 2nd edn. Chapman & Hall/CRC NoGoogle Scholar
  29. Grammel R (1990) Zusammenhänge zwischen Wachstumsbedingungen und holztechnologischen Eigenschaften der Fichte (Relationship between growth conditions and wood properties of Norway spruce) (In German). Forstwiss Centbl 109:119–129.  https://doi.org/10.1007/BF02741625 CrossRefGoogle Scholar
  30. Hapla F (1985) Radiographisch-densitometrische Holzeigenschaftsuntersuchungen an Douglasien aus unterschiedlich durchforsteten Versuchsflächen (Investigations on properties of Douglas-fir in differently thinned experimental areas by X-ray densitometric method) (In German). Holz Roh Werkst 43:9–15.  https://doi.org/10.1007/BF02609013 CrossRefGoogle Scholar
  31. Henin JM, Pollet C, Jourez B, Hébert J (2018) Impact of tree growth rate on the mechanical properties of Douglas fir lumber in Belgium. Forests 9:342.  https://doi.org/10.3390/f9060342 CrossRefGoogle Scholar
  32. Herman M, Dutilleul P, Avella-Shaw T (1998) Growth rate effects on temporal trajectories of ring width, wood density, and mean tracheid length in Norway spruce (Picea abies (l.) karst.). Wood Fiber Sci 30:6–17Google Scholar
  33. Høibø O, Vestøl GI, Fischer C, Fjeld L, Øvrum A (2014) Bending properties and strength grading of Norway spruce: variation within and between stands. Can J For Res 44:128–135.  https://doi.org/10.1139/cjfr-2013-0187 CrossRefGoogle Scholar
  34. Jaakkola T, Mäkinen H, Saranpää P (2005a) Wood density in Norway spruce: changes with thinning intensity and tree age. Can J For Res 35:1767–1778.  https://doi.org/10.1139/x05-118 CrossRefGoogle Scholar
  35. Jaakkola T, Mäkinen H, Sarén MP, Saranpää P (2005b) Does thinning intensity affect the tracheid dimensions of Norway spruce? Can J For Res 35:2685–2697.  https://doi.org/10.1139/x05-182 CrossRefGoogle Scholar
  36. Jaakkola T, Mäkinen H, Saranpää P (2006) Wood density of Norway spruce: responses to timing and intensity of first commercial thinning and fertilisation. For Ecol Manag 237:513–521.  https://doi.org/10.1016/j.foreco.2006.09.083 CrossRefGoogle Scholar
  37. Johansson K (1993) Influence of initial spacing and tree class on the basic density of Picea abies. Scand J For Res 8:18–27.  https://doi.org/10.1080/02827589309382752 CrossRefGoogle Scholar
  38. Jyske T, Mäkinen H, Saranpää P (2008) Wood density within Norway spruce stems. Silva Fenn 42:439–455CrossRefGoogle Scholar
  39. Kimberley MO, Cown DJ, McKinley RB, Moore JR, Dowling LJ (2015) Modelling variation in wood density within and among trees in stands of New Zealand-grown radiata pine. N Z J For Sci 45.  https://doi.org/10.1186/s40490-015-0053-8
  40. Kimberley M, McKinley R, Cown D, Moore J (2017) Modelling the variation in wood density of New Zealand-grown Douglas-fir. N Z J For Sci 47.  https://doi.org/10.1186/s40490-017-0096-0
  41. Kruschke J (2014) Doing Bayesian data analysis: a tutorial with R, JAGS, and Stan, 2nd edn. Academic PressGoogle Scholar
  42. Lara W, Bravo F, Sierra C (2015) measuRing: an R package to measure tree-ring widths from scanned images. Dendrochronologia 34:43–50.  https://doi.org/10.1016/j.dendro.2015.04.002 CrossRefGoogle Scholar
  43. Larsson D, Ohlsson S, Perstorper M, Brudin J (1998) Mechanical properties of sawn timber from Norway spruce. Holz Roh Werkst 56:331–338.  https://doi.org/10.1007/s001070050329 CrossRefGoogle Scholar
  44. Lasserre JP, Mason EG, Watt MS (2005) The effects of genotype and spacing on Pinus radiata [D. Don] corewood stiffness in an 11-year old experiment. For Ecol Manag 205:375–383.  https://doi.org/10.1016/j.foreco.2004.10.037 CrossRefGoogle Scholar
  45. Lasserre JP, Mason EG, Watt MS (2008) Influence of the main and interactive effects of site, stand stocking and clone on Pinus radiata D. Don corewood modulus of elasticity. For Ecol Manag 255:3455–3459.  https://doi.org/10.1016/j.foreco.2008.02.022 CrossRefGoogle Scholar
  46. Lasserre JP, Mason EG, Watt MS, Moore JR (2009) Influence of initial planting spacing and genotype on microfibril angle, wood density, fibre properties and modulus of elasticity in Pinus radiata D. Don corewood. For Ecol Manag 258:1924–1931.  https://doi.org/10.1016/j.foreco.2009.07.028 CrossRefGoogle Scholar
  47. Lindström H (1996) Basic density of Norway spruce. Part II. Predicted by stem taper, mean growth ring width, and factors related to crown development. Wood Fiber Sci 28:240–251Google Scholar
  48. Lindström H, Reale M, Grekin M (2009) Using non-destructive testing to assess modulus of elasticity of Pinus sylvestris trees. Scand J For Res 24:247–257.  https://doi.org/10.1080/02827580902758869 CrossRefGoogle Scholar
  49. Liu C, Zhang SY, Cloutier A, Rycabel T (2007) Modeling lumber bending stiffness and strength in natural black spruce stands using stand and tree characteristics. For Ecol Manag 242:648–655.  https://doi.org/10.1016/j.foreco.2007.01.077 CrossRefGoogle Scholar
  50. Lowell EC, Todoroki CL, Dykstra DP, Briggs DG (2014) Linking acoustic velocity of standing Douglas-fir trees to veneer stiffness: a tree-log-product study across thinning treatments. N Z J For Sci 44:1.  https://doi.org/10.1186/1179-5395-44-1 CrossRefGoogle Scholar
  51. Macdonald E (2002) A review of the effects of silviculture on timber quality of Sitka spruce. Forestry 75:107–138.  https://doi.org/10.1093/forestry/75.2.107 CrossRefGoogle Scholar
  52. Makinen H, Verkasalo E, Tuimala A (2014) Effects of pruning in Norway spruce on tree growth and grading of sawn boards in Finland. Forestry 87:417–424.  https://doi.org/10.1093/forestry/cpt062 CrossRefGoogle Scholar
  53. McElreath R (2016) Statistical rethinking: a Bayesian course with examples in R and Stan. Chapman & Hall/CRC Texts in Statistical Science, CRC PressGoogle Scholar
  54. Moore J, Achim A, Lyon A, Mochan S, Gardiner B (2009) Effects of early re-spacing on the physical and mechanical properties of Sitka spruce structural timber. For Ecol Manag 258:1174–1180.  https://doi.org/10.1016/j.foreco.2009.06.009 CrossRefGoogle Scholar
  55. Moore JR, Cown DJ, McKinley RB, Sabatia CO (2015) Effects of stand density and seedlot on three wood properties of young radiata pine grown at a dry-land site in New Zealand. N Z J For Sci 45:4.  https://doi.org/10.1186/s40490-015-0035-x CrossRefGoogle Scholar
  56. Neuwirth B, Schweingruber FH, Winiger M (2007) Spatial patterns of central European pointer years from 1901 to 1971. Dendrochronologia 24:79–89.  https://doi.org/10.1016/j.dendro.2006.05.004 CrossRefGoogle Scholar
  57. Nocetti M, Bacher M, Brunetti M, Crivellaro A, Van de Kuilen JWG (2010) Machine grading of Italian structural timber: preliminary results on different wood species. World Conference on Timber Engineering, Riva del Garda, Italy, p 8Google Scholar
  58. Pape R (1999a) Effects of thinning regime on the wood properties and stem quality of Picea abies. Scand J For Res 14:38–50.  https://doi.org/10.1080/02827589908540807 CrossRefGoogle Scholar
  59. Pape R (1999b) Influence of thinning and tree diameter class on the development of basic density and annual ring width in Picea abies. Scand J For Res 14:27–37.  https://doi.org/10.1080/02827589908540806 CrossRefGoogle Scholar
  60. Peltola H, Kilpeläinen A, Sauvala K, Räisänen T, Ikonen VP (2007) Effects of early thinning regime and tree status on the radial growth and wood density of scots pine. Silva Fenn 41:489–505CrossRefGoogle Scholar
  61. Piispanen R, Heinonen J, Valkonen S, Mäkinen H, Lundqvist SO (2014) Wood density of Norway spruce in uneven-aged stands 1. Can J For Res 144:136–144.  https://doi.org/10.1139/cjfr-2013-0201 CrossRefGoogle Scholar
  62. Pretzsch H, Rais A (2016) Wood quality in complex forests versus even-aged monocultures: review and perspectives. Wood Sci Technol 50:1–36.  https://doi.org/10.1007/s00226-016-0827-z CrossRefGoogle Scholar
  63. R Core Team (2018) R: a language and environment for statistical computing, ViennaGoogle Scholar
  64. Rais A, Poschenrieder W, Pretzsch H, van de Kuilen JWG (2014) Influence of initial plant density on sawn timber properties for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Ann For Sci 71:617–626.  https://doi.org/10.1007/s13595-014-0362-8 CrossRefGoogle Scholar
  65. Roblot G, Coudegnat D, Bleron L, Collet R (2008) Evaluation of the visual stress grading standard on French spruce (Picea excelsa) and Douglas-fir (Pseudotsuga menziesii) sawn timber. Ann For Sci 65:812–812.  https://doi.org/10.1051/forest:2008071 CrossRefGoogle Scholar
  66. Roth B, Li X, Huber D, Peter G (2007) Effects of management intensity, genetics and planting density on wood stiffness in a plantation of juvenile loblolly pine in the southeastern USA. For Ecol Manag 246:155–162.  https://doi.org/10.1016/j.foreco.2007.03.028 CrossRefGoogle Scholar
  67. Savill PS, Sandels AJ (1983) The influence of early respacing on the wood density of Sitka spruce. Forestry 56:109–120CrossRefGoogle Scholar
  68. Schweingruber FH, Eckstein D, Serre-Bachet F, Bräker OU (1990) Identification, presentation and interpretation of event years and pointer years in dendrochronology. Dendrochronologia 8:9–38Google Scholar
  69. Simic K, Gendvilas V, O’Reilly C, Nieuwenhuis M, Harte AM (2017) The influence of planting density on modulus of elasticity of structural timber from Irish-grown Sitka spruce. Int J Des Nat Ecodyn 12:438–447.  https://doi.org/10.2495/DNE-V12-N4-438-447 CrossRefGoogle Scholar
  70. Simic K, Gendvilas V, O’Reilly C, Harte AM (2018) Predicting structural timber grade-determining properties using acoustic and density measurements on young Sitka spruce trees and logs. Holzforschung.  https://doi.org/10.1515/hf-2018-0073
  71. Simpson HL, Denne MP (1997) Variation of ring width and specific gravity within trees from unthinned Sitka spruce spacing trial in Clocaenog, North Wales. Forestry 70:31–45CrossRefGoogle Scholar
  72. Stan Development Team (2018) RStan: the R interface to Stan. R package version 2.17.3Google Scholar
  73. Torquato LP, Auty D, Hernandez RE, Duchesne I, Pothier D, Achim A (2014) Black spruce trees from fire-origin stands have higher wood mechanical properties than those from older, irregular stands. Can J For Res 44:118–127.  https://doi.org/10.1139/cjfr-2013-0164 CrossRefGoogle Scholar
  74. van der Maaten-Theunissen M, van der Maaten E, Bouriaud O (2015) pointRes: an R package to analyze pointer years and components of resilience. Dendrochronologia 35:34–38.  https://doi.org/10.1016/j.dendro.2015.05.006 CrossRefGoogle Scholar
  75. Vincent M, Krause C, Koubaa A (2011) Variation in black spruce (Picea mariana (Mill) BSP) wood quality after thinning. Ann For Sci 68:1115.  https://doi.org/10.1007/s13595-011-01276 CrossRefGoogle Scholar
  76. Watt MS, Moore JR, Façon JP, Downes GM, Clinton PW, Coker G, Davis MR, Simcock R, Parfitt RL, Dando J, Mason EG, Bown HE (2006) Modelling the influence of stand structural, edaphic and climatic influences on juvenile Pinus radiata dynamic modulus of elasticity. For Ecol Manag 229:136–144.  https://doi.org/10.1016/j.foreco.2006.03.016 CrossRefGoogle Scholar
  77. Wilhelmsson L, Arlinger J (2002) Models for predicting wood properties in stems of Picea abies and Pinus sylvestris in Sweden. Scand J For Res 17:330–350CrossRefGoogle Scholar
  78. Zeller L, Ammer C, Annighöfer P, Biber P, Marshall J, Schütze G, del Rio Gaztelurrutia M, Pretzsch H (2017) Tree ring wood density of Scots pine and European beech lower in mixed-species stands compared with monocultures. For Ecol Manag 400:363–374.  https://doi.org/10.1016/j.foreco.2017.06.018 CrossRefGoogle Scholar
  79. Zhang H, Ma S, Wu Y (eds) (2011) Building materials in civil engineering. Woodhead Publishing in Materials, Woodhead Pub. ; Science Press, Oxford ; Philadelphia : Beijing oCLC: ocn666239692Google Scholar
  80. Zobel B, van Buijtenen J (1989) Wood variation its causes and control. Springer-Verlag, BerlinCrossRefGoogle Scholar

Copyright information

© INRA and Springer-Verlag France SAS, part of Springer Nature 2019

Authors and Affiliations

  1. 1.College of Engineering and Informatics and Ryan InstituteNational University of Ireland GalwayGalwayIreland
  2. 2.Forestry Development DepartmentAthenryIreland

Personalised recommendations