Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Effect of radial increment core diameter on tracheid length measurement in Norway spruce


The effect of radial increment core diameter (comparing the effects of 12, 8 and 4 mm diameters, with sampling from chips used as a control) on the measurement of tracheid mean length and the percentage of broken tracheids was examined for mature wood of Norway spruce. Two methods of measuring tracheid length were used: image analysis, in which arithmetic mean length (AML) was calculated for unbroken tracheids, and the Kajaani FS-200, in which AML was calculated for all tracheids, regardless of damage. In addition to AML, length weighted mean length (LWML) was calculated for the Kajaani.

Almost 70 % of all tracheids remained undamaged when the 12 mm increment core was used. This was 18 % units less than for chips. Proportion of broken tracheids increased as core diameter decreased, and for the 4 mm increment core 30 per cent of all tracheids remained undamaged.

All increment core diameters tested gave LWML values that were significantly lower than the control. For AML by Kajaani, all mean values were about 50 percent lower than corresponding LWML or image analysis values, thus showing the direct influence of broken tracheids. However, only the 4 and 8 mm increment cores differed significantly from the control. For unbroken tracheids measured by image analysis, the 4 mm increment core gave a significantly lower value than the control, thus showing the indirect influence of broken tracheids. Values obtained from the 8 and 12 :mm increment cores did not differ significantly from the control.

This is a preview of subscription content, log in to check access.


  1. Anonymus (1991) Fiber length of pulp and paper by automated optical analyzer. TAPPI, T 271 pm-91

  2. Atmer, B.; Thörngvist, T. (1982) The properties of tracheids in spruce (Picea abies Karst.) and pine (Pinus sylvestris L.). Swedish University of Agricultural Sciences. Dept. of For. Prod. Report 134. ISBN 91-576-1272-2. 59 pp. (In Swedish with English summary)

  3. Dorst, L.;Smeulders, A. W. M. (1987) Length estimators for digitized contours. Computer Vision, Graphics, and Image Processing 40: 311–333

  4. Frimpong-Mensah, K. (1987) Fibre length and basic density variation in the wood of Norway spruce (Picea abies L. Karst.) from northern Norway. Comm. Norwegian For. Res. Inst. 40.1. 25 pp

  5. Glomb, J. W.;Mulligan, D. D. (1989) Paper and Paperboard. In: Schniewind, A. P. (Ed.): Concise Encyclopidia of Wood & Wood-Based Materials. pp 207–216. Pergamon Press, Oxford, UK. ISBN 0-08-034726-6

  6. Hart, C. A.;Hafley, W. L. (1967) Estimation of wood fiber length from increment cores. Tappi Journal, vol 50, no 12: 615–618

  7. Hartler, N.;Stade, Y. (1979) Chip specification for various pulping processes. In: Hatton, J. W. (Ed.): Chip Quality Monograph. Pulp and Paper Technology Series, Joint Textbook Committee of the Paper Industry, pp 273–301. Montreal, Quebec, Canada

  8. Heikkurinen, A.; Levlin, J. -E.; Paulapuro, H. (1990) Principles and methods in pulp characterization — basic fiber properties. In: Proc. The World Pulp and Paper Week, 24th EUCEPA Conf, May 8–11 1990. pp 174–187. Stockholm, Sweden

  9. Kerekes, R. J.;Schnell, C. J. (1995) Effects of fiber length and coarseness on pulp flocculation. Tappi Journal, vol 78, no 2: 133–139

  10. Norušis, M. J. (1993) SPSS for Windows, Release 6.0. SPSS Inc., 444 N Michigan Ave., Chicago, Illinois 60611, USA. ISBN 0-13-178856-6

  11. Paavilainen, L. (1988) Importance of coarseness and fiber length in papermaking. In: Int. Process and Product Quality Conference. TAPPI, Oct. 23–26 1988, pp 99–109. Savannah GA

  12. Piirainen, R.;Paavilainen, L. (1986) Fiber length measurement in the pulp and paper industry. In: Int. Process and Materials Quality Evaluations Conference. TAPPI, Sept. 21–24 1986, pp 67–73. Atlanta

  13. Polge, H. (1967) Determination of fiberlength using 5 mm increment core. Tappi Journal, vol. 50, no 9: 460–462

  14. Taylor, F. W.;Wang, E. I. C.;Yanchuk, A.;Micko, M. M. (1982) Specific gravity and tracheid length variation of white spruce in Alberta. Can. J. For. Res. 12: 561–566

  15. Yang, K. C.;Hazenberg, G. (1994) Impact of spacing on tracheid length, relative density, and growth rate of juvenile and mature wood inPicea mariana. Can. J. For. Res. 24: 996–1007

  16. Zar, J. H. (1984) Biostatistical analysis. Second edition. Prentice-Hall Inc. Englewood Cliffs, New Jersey. ISBN 0-13-077595-9. 718 pp

  17. Zobel, B. J.;van Buijtenen, J. P. (1989) Wood variation, its causes and control. Springer Series in Wood Science, Springer Verlag, Berlin, Germany. ISBN 3-540-50298-X. 363 pp

Download references

Author information

Additional information

We thank Öjvind Sundvall, Gunilla Ericsson and Birgitta Lundgren, MoDo Research and Development, Örnsköldsvik, for technical assistance and Professors Erik G. Stahl, Dept. of Forest Yield Research, SLU Garpenberg, and Björn Elfving, Dept. of Silviculture, SLU Umeå, for their helpful comments on the manuscript. We are also grateful to Dr. Staffan Uvell, Dept. of Mathematical Statistics, Umeå University, for statistical advice. Language was revised by Proper English Ltd., Alfta. Funding was provided by MoDo Ltd. and SLU, Faculty of Forestry, Graduate School in Wood and Fiber Science.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Bergqvist, G., Bergsten, U. & Ahlqvist, B. Effect of radial increment core diameter on tracheid length measurement in Norway spruce. Wood Sci.Technol. 31, 241–250 (1997).

Download citation


  • Image Analysis
  • Direct Influence
  • Length Measurement
  • Core Diameter
  • Indirect Influence