Wood Science and Technology

, Volume 49, Issue 4, pp 739–753 | Cite as

Collection of wood quality data by X-ray densitometry: a case study with three southern pines

  • Thomas L. Eberhardt
  • Lisa J. Samuelson


X-ray densitometry is a technique often used in tree growth and wood quality studies to incrementally measure density (specific gravity) along a radial strip of wood. Protocols for this technique vary between laboratories because of differences in species, equipment, tree age, and other factors. Here, the application of X-ray densitometry is discussed in terms of a case study specific to the southern pines, whereby loblolly (Pinus taeda L), longleaf (Pinus palustris Mill.), and slash (Pinus elliottii Engelm.) pine wood cores were analyzed using an automated system. Objectives of this study included an assessment of the potential impacts on whole-core wood quality data from wood core extraction and use of two different demarcation methods (threshold and inflection point) for the earlywood–latewood transition. Wood core extraction before X-ray densitometry showed minimal impact on the shapes of individual ring profiles, and whole-core wood quality data were essentially unchanged. An assessment of the inflection point method employed for determining the earlywood–latewood transition point in the X-ray densitometry data demonstrated that the growth ring profiles for the southern pines are not amenable to polynomial fitting. Indeed, in the southern pines, the earlywood–latewood transitions are as equally abrupt as the latewood–earlywood transitions. Accordingly, a threshold density deemed appropriate to define the onset of a growth ring would be equally appropriate to define the onset of latewood formation.


Specific Gravity Growth Ring Juvenile Wood Mature Wood Ring Number 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Wood cores were processed by Edward Andrews. Michael Thompson performed X-ray densitometry, and Charles Grier processed the resultant data in consultation with Ray Souter. Karen Reed assisted with wood core extractions and manuscript review. The authors wish to thank Kurt Johnsen for help in coordinating core collection at the Harrison Experimental Forest.


  1. Adamopoulos S, Milios E, Doganos D, Bistinas I (2009) Ring width, latewood proportion and dry density in stems of Pinus brutia Ten. Eur J Wood Prod 67:471–477Google Scholar
  2. Antony F, Schimleck LR, Daniels RF (2012) A comparison of the earlywood-latewood demarcation methods—a case study in loblolly pine. IAWA J 33(2):187–195Google Scholar
  3. ASTM (1993) D2395, standard test methods for specific gravity of wood and wood-based materials. American Society of Testing and Materials, West ConshohockenGoogle Scholar
  4. Bergsten U, Lindeberg J, Rindby A, Evans R (2001) Batch measurements of wood density on intact or prepared drill cores using X-ray microdensitometry. Wood Sci Technol 35:435–452CrossRefGoogle Scholar
  5. Biblis EJ, Carino H, Teeter L (1998) Comparative economic analysis of two management options for loblolly pine timber plantations. Forest Prod J 48(4):29–32Google Scholar
  6. Bouffier L, Rozenberg P, Raffin A, Kremer A (2008) Wood density variability in successive breeding populations of maritime pine. Can J Forest Res 38:2148–2158CrossRefGoogle Scholar
  7. Chaffey N (1999) Cambium: old challenges—new opportunities. Trees-Struct Funct 13:138–151CrossRefGoogle Scholar
  8. Clark A, Saucier JR (1989) Influence of initial planting density, geographic location, and species on juvenile wood formation in southern pine. Forest Prod J 39(7/8):42–48Google Scholar
  9. Clark A, Daniels RF, Jordan L (2006) Juvenile/mature wood transition in loblolly pine as defined by annual ring specific gravity, proportion of latewood, and microfibril angle. Wood Fiber Sci 38(2):292–299Google Scholar
  10. Cole DE, Zobel BJ, Roberds JH (1966) Slash, loblolly, and longleaf pine in a mixed natural stand; a comparison of their wood properties, pulp yields, and paper properties. Tappi J 49(4):161–166Google Scholar
  11. Eberhardt TL, Sheridan PM, Mahfouz JM, So C-L (2007) Old resinous turpentine stumps as an indicator of the range of longleaf pine in southeastern Virginia. In: Estes BL, Kush JS (eds) Proceedings of the sixth longleaf alliance regional conference, Tifton, GA. Longleaf Alliance Report No. 10, pp 79–82Google Scholar
  12. Eberhardt TL, Sheridan PM, Bhuta AAR (2011) Revivification of a method for identifying longleaf pine timber and its application to southern pine relicts in southeastern Virginia. Can J Forest Res 41:2440–2447CrossRefGoogle Scholar
  13. Forest Products Laboratory (2010) Wood handbook: wood as an engineering material. General technical report FPL-GTR-190, USDA Forest Service, Forest Products Laboratory, Madison, WIGoogle Scholar
  14. Franceschini T, Bontemps J-D, Leban J-M (2012) Transient historical decrease in earlywood and latewood density and unstable sensitivity to summer temperature for Norway spruce in northeastern France. Can J Forest Res 42:219–226CrossRefGoogle Scholar
  15. Franceschini T, Longuetaud F, Bontemps J-D, Bouriaud O, Caritey B-D, Leban J-M (2013) Effect of ring width, cambial age, and climatic variables on the within-ring wood density profile of Norway spruce Picea abies (L.) Karst. Trees-Struct Funct 27:913–925CrossRefGoogle Scholar
  16. Fujimoto T, Koga S (2010) An application of mixed-effects model to evaluate the effects of initial spacing on radial variation in wood density in Japanese larch (Larix kaempferi). J Wood Sci 56:7–14CrossRefGoogle Scholar
  17. Gapare WJ, Wu HX, Abarquez A (2006) Genetic control of the time of transition from juvenile to mature wood in Pinus radiata D. Don. Ann Forest Sci 63:871–878CrossRefGoogle Scholar
  18. Gonzalez-Benecke CA, Riveros-Walker AJ, Martin TA, Peter GF (2015) Automated quantification of intra-annual density fluctuations using microdensity profiles of mature Pinus taeda in a replicated irrigation experiment. Trees-Struct Funct 29:185–197CrossRefGoogle Scholar
  19. Grabner M, Wimmer R, Gierlinger N, Evans R, Downes G (2005) Heartwood extractives in larch and effects on X-ray densitometry. Can J Forest Res 35:2781–2786CrossRefGoogle Scholar
  20. Guller B, Isik K, Cetinay S (2012) Variations in the radial growth and wood density components in relation to cambial age in 30-year-old Pinus brutia Ten. at two test sites. Trees-Struct Funct 26:975–986CrossRefGoogle Scholar
  21. Harms WR, Whitesell CD, DeBell DS (2000) Growth and development of loblolly pine in a spacing trial planted in Hawaii. Forest Ecol Manag 126:13–24CrossRefGoogle Scholar
  22. Helama S, Vartiainen M, Kolström T, Meriläinen J (2010) Dendrochronological investigation of wood extractives. Wood Sci Technol 44:335–351CrossRefGoogle Scholar
  23. Hodge GR, Purnell RC (1993) Genetic parameter estimates for wood density, transition age, and radial growth in slash pine. Can J Forest Res 23:1881–1891CrossRefGoogle Scholar
  24. Ifju G, Labosky P Jr (1972) A study of loblolly pine growth increments: part 1. wood and tracheid characteristics. Tappi J 55(4):524–529Google Scholar
  25. Ivković M, Rozenberg P (2004) A method for describing and modelling of within-ring wood density distribution in clones of three coniferous species. Ann For Sci 61:759–769CrossRefGoogle Scholar
  26. Jagels R, Telewski FW (1990) Computer-aided image analysis of tree rings. In: Cook ER, Kairiukstis LA (eds) Methods of dendrochronology: applications in the environmental sciences. Kluwer Academic Publishers, Boston, pp 76–93Google Scholar
  27. Jordan L, Clark A, Schimleck LR, Hall DB, Daniels RF (2008) Regional variation in wood specific gravity of planted loblolly pine in the United States. Can J Forest Res 38:698–710CrossRefGoogle Scholar
  28. Kantavichai R, Briggs D, Turnblom E (2010) Modeling effects of soil, climate, and silviculture on growth ring specific gravity of Douglas-fir on a drought-prone site in Western Washington. Forest Ecol Manag 259:1085–1092CrossRefGoogle Scholar
  29. Koubaa A, Zhang SYT, Makni S (2002) Defining the transition from earlywood to latewood in black spruce based on intra-ring wood density profiles from X-ray densitometry. Ann Forest Sci 59:511–518CrossRefGoogle Scholar
  30. Koubaa A, Isabel N, Zhang SY, Beaulieu J, Bousquet J (2005) Transition from juvenile to mature wood in black spruce (Picea mariana (Mill.) B.S.P.). Wood Fib Sci 37(3):445–455Google Scholar
  31. Kubler H (1980) Wood as building and hobby material. John Wiley and Sons, New YorkGoogle Scholar
  32. Kumar S (2002) Earlywood-latewood demarcation criteria and their effect on genetic parameters of growth ring density components and efficiency of selection for end-of-rotation density of radiata pine. Silvae Genet 51:5–6Google Scholar
  33. Larson PR (1969) Wood formation and the concept of wood quality. Yale University, School of Forestry, Bulletin No. 74, Yale University, New Haven, CTGoogle Scholar
  34. Love-Myers KR, Clark A, Schimleck LR, Jokela EJ, Daniels RF (2009) Specific gravity responses of slash and loblolly pine following mid-rotation fertilization. Forest Ecol Manag 257:2342–2349CrossRefGoogle Scholar
  35. Mora CR, Allen HL, Daniels RF, Clark A (2007) Modeling corewood-outerwood transition in loblolly pine using wood specific gravity. Can J Forest Res 37:999–1011CrossRefGoogle Scholar
  36. Mork E (1928) The quality of spruce wood with special regard to pulpwood. Der Papier-Fabrikant 48:741–747Google Scholar
  37. Mothe F, Duchanois G, Zannier B, Leban J-M (1998) Microdensitometric analysis of wood samples: data computation method used at Inra-ERQB (CERD program). Ann Sci Forest 55:301–313CrossRefGoogle Scholar
  38. Panshin AJ, de Zeeuw C (1980) Textbook of wood technology, 4th edn. McGraw-Hill, New YorkGoogle Scholar
  39. Park Y-I, Dallaire G, Morin H (2006) A method for multiple intra-ring demarcation of coniferous trees. Ann Forest Sci 63:9–14CrossRefGoogle Scholar
  40. Pernestål K, Jonsson B, Larsson B (1995) A simple model for density of annual rings. Wood Sci Technol 29:441–449CrossRefGoogle Scholar
  41. Pettersen RC (1984) The chemical composition of wood. In: Rowell R (ed) The chemistry of solid wood. American Chemical Society, Washington, D.C., pp 2–126Google Scholar
  42. Rozenberg P, Schüte G, Ivkovich M, Bastien C, Bastien J-C (2004) Clonal variation of indirect cambium reaction to within-growing season temperature changes in Douglas-fir. Forestry 77(4):257–268CrossRefGoogle Scholar
  43. Samuelson LJ, Eberhardt TL, Butnor JR, Stokes TA, Johnsen KH (2010) Maximum growth potential in loblolly pine: results from a 47-year-old spacing study in Hawaii. Can J Forest Res 40:1914–1929CrossRefGoogle Scholar
  44. Samuelson LJ, Stokes TA, Johnsen KH (2012) Ecophysiological comparison of 50-year-old longleaf pine, slash pine and loblolly pine. Forest Ecol Manag 274:108–115CrossRefGoogle Scholar
  45. Samuelson LJ, Eberhardt TL, Bartkowiak SM, Johnsen KH (2013) Relationships between climate, radial growth and wood properties of mature loblolly pine in Hawaii and a northern and southern site in the southeastern United States. Forest Ecol Manag 310:786–795CrossRefGoogle Scholar
  46. Schmidtling RC (1973) Intensive culture increases growth without affecting wood quality of young southern pines. Can J Forest Res 3:565–573CrossRefGoogle Scholar
  47. Spurr SH, Hsiung W-Y (1954) Growth rate and specific gravity in confers. J Forest 52(3):191–200Google Scholar
  48. Tasissa G, Burkhart HE (1998) Modeling thinning effects on ring specific gravity of loblolly pine (Pinus taeda L.). Forest Sci 44(2):212–223Google Scholar
  49. Williamson GB, Wiemann MC (2010) Measuring wood specific gravity…correctly. Am J Bot 97(3):519–524PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg (outside the USA) 2015

Authors and Affiliations

  1. 1.Southern Research StationUSDA Forest ServicePinevilleUSA
  2. 2.School of Forestry and Wildlife SciencesAuburn UniversityAuburnUSA
  3. 3.Forest Products LaboratoryUSDA Forest ServiceMadisonUSA

Personalised recommendations