Theoretical Wood Densitometry: III. Mean Density and Density Variation on Stem Cross-Sections
Keywords:
Stem profile, normalization, weighting, latewood, annual ringAbstract
Wood densitometry measures micro-scale densities in specimens that are subsamples drawn from trees receiving various treatments. However, forestry research often requires macro-scale wood density in experimental units for testing for significance of treatment effects. Acquisition of desired macro-scale wood density expressions necessitates mathematical manipulation. To facilitate direct calculation of mean density and density variation in an individual segment or in an arbitrary aggregate of segments and to derive indirect estimation of density mean and variation in annuli and cross-sections, wood density profiles have been modeled as continuous functions whose values are linearly interpolated. Theoretical macro-scale wood density expressions have been derived from applying normalization procedures and both linear and quadratic weights to micro-scale densities. Examples demonstrate the use of newly developed equations to calculate density means and root-mean-squares in single and multiple densitometric data sets.References
American Society for Testing and Materials. 1983. Standard test methods for specific gravity of wood and wood-base materials. D2395-83.nBennett, W. E. 1955. Atomics 6(5):134. [Original not seen. See Cameron et al. 1959]nBersenev, A. P., and A. G. Fokina. 1958. Derev. Prom. (Woodworking Industry) 7(8):9. [Original not seen. See Cameron et al. 1959]nBodner, J. 1983. Effect of thinning and fertilization on wood properties and intra-ring characteristics in young Douglas-fir. Unpubl. M.S. thesis, Oregon State Univ., Corvallis. 114 pp.nBrazier, J. D. 1969. Some considerations in appraising within-ring density. Proceedings, Second World Consultation on Forest Tree Breeding, Washington, DC. FAO-IUFRO: 381-391.nCameron, J. F., P. F. Beery, and E. W. J. Phillips. 1959. The determination of wood density using beta rays. Holzforschung 13(3):78-84.nConkey, L. E. 1979. Response of tree-ring density to climate in Maine, USA. Tree-Ring Bull. 39:29-38.nCown, D. J. 1974. Comparison of the effects of two thinning regimes on wood properties of radiata pine. N.Z. J. For. Sci. 4(3):540-551.nCown, D. J., and B. C. Clement. 1983. A wood densitometer using direct scanning with X-rays. Wood Sci. Technol. 17:91-99.nDinwoodie, J. M. 1968. Why measure density critically? J. Inst. Wood Sci. 4(3):3-5.nEchols, R. M. 1972. Product suitability of wood … determined by density gradients across growth rings. USDA For. Serv. Res. Note PSW-273. 6 pp.nElliott, G. K., and S. E. G. Brook. 1967. Microphotometric technique for growth-ring analysis. J. Inst. Wood Sci. 18:24-43.nFarrington, A. 1980. Wood and digester factors affecting kraft pulp quality and uniformity. Appita 34(1):40-44.nFerrand, J.-C. 1982. [Considerations on wood density. Part 2: Calculation of density and of its heterogeneity.] Holzforschung 36(3):153-157.nFletcher, J. M., and J. F. Hughes. 1970. Uses of X-rays for density determinations and dendrochronology. In Tree-ring analysis with special reference to northwest America, Univ. B.C., For. Bull. 7:41-54.nGonzalez, J. S. 1988. Circumferential variation in the relative density of lodgepole pine. Can. J. For. Res. 19:276-279.nHarris, J. M. 1969. The use of beta rays in determining wood properties—Part 3. Summarizing radial variation in wood density. N.Z. J. Sci. 12:419-431.nHeger, L., M. L. Parker, and R. W. Kennedy. 1974. X-ray densitometry—A technique and an example of application. Wood Sci. 7(2):140-148.nHoag, M., and M. D. McKimmy. 1988. Direct scanning X-ray densitometry of thin wood sections. For. Prod. J. 38(1):23-26.nKanowski, P. 1985. Densitometric analysis of a large number of wood samples. J. Inst. Wood Sci. 10(4):145-151.nKlem, G. G., F. Loschbrandt, and O. Bade. 1945. Undersoklser av granvirke i forbindelse med slipe-og sulfitkokeforsok. Med. Norske Skogforsoksv 31(9):1-127. [Original not seen. See Elliott and Brook 1967]nKorn, G. A., and T. M. Korn. 1968. Mathematical handbook for scientists and engineers. McGraw-Hill Brook Co., New York. 1130 pp.nLakatosh, B. K. 1956. Derev. Prom. (Woodworking Industry) 5(10):13. [Original not seen. See Cameron et al. 1959]nLakatosh, B. K. 1957. Derev. Prom. (Woodworking Industry) 6(5):9. [Original not seen. See Cameron et al. 1959]nLaufenberg, T. L. 1986. Using gamma radiation to measure density gradients in reconstituted wood products. For. Prod. J. 36(2):59-62.nLawhon, W. T. 1973. Radial growth and wood density of white pine in relation to coal-derived environmental pollutants. Unpubl. Ph.D. dissertation. Univ. Tenn., Knoxville. 109 pp.nMay, H.-A., H.-P. Schatzler, and W. Kuhn. 1976. [Measurement of the density profile of chipboard by means of gamma rays.] Kerntechnik 18(11):494.nMork, E. 1928. Die Qualitat des Fichtenholzes unter Besonderer Rucksichtenahmauf Scheif- und Papierholz. Papierfabrikant 26(48):741-747.nMoura, V. P. G., R. D. Barnes, and J. S. Birks. 1987. A comparison of three methods of assessing wood density in provenances of Eucalyptus camaldulensis Dehnh. and other Eucalyptus species in Brazil. Aust. For. Res. 17:83-90.nNearn, W. T., and K. Bassett. 1968. X-ray determination and use of surface-to-surface density profile in fiberboard. For. Prod. J. 18(1):73-74.nNicholls, J. W. P. 1971. The effect of environmental factors on wood characteristics. I. The influence of irrigation on Pinus radiata from South Australia. Silvae Genet. 20(1/2):26-33.nOhta, S. 1978. [The observation of tree ring structure of soft X-ray densitom I. The effects of air pollution on annual ring structure.] J. Jap. Wood Res. Soc. 24(7):429-434.nOlson, J. R., and D. G. Arganbright. 1977. The uniformity factor—A proposed method for expressing variations in specific gravity. Wood Fiber Sci. 9(3):202-210.nPalmer, E. R., and S. Ganguli. 1988. Pulping characteristics of Pinus patula grown in Zimbabwe. Overseas Development Natural Resources Institute, Kent, United Kingdom. ODNRI Bull. No. 8. 32 pp.nPhillips, E. W. J. 1960. The beta ray method of determining the density of wood and the proportion of summer wood. J. Inst. Wood Sci. 1(5):16-28.nPolge, H. 1965. Study of wood density variations by densitometric analysis of X-ray negatives of samples taken with a Pressler auger. Paper presented at the meeting of IUFRO Sec. 41, Oct., Melbourne. 19 pp.nPolge, H. 1970. The use of X-ray densitometric methods in dendrochronology. Tree Ring Bull. 30(4):1-10.nPolge, H., and S. Garros. 1971. [Influence of defoliation on wood structure of maritime pine.] Ann. Sci. For. 28(2):195-206.nPurcell, E. J. 1965. Calculus with analytic geometry. Appleton-Century-Crofts, New York. 843 pp.nRudman, P., and F. H. McKinnell. 1970. Effect of fertilizers on wood density of young radiata pine. Aust. For. 34(3):170-178.nSmith, D. M. 1954. Maximum moisture content method for determining specific gravity of small wood samples. U.S. For. Prod. Lab. Rep. No. 2014.nTaylor, F. W. 1973. Variations in the anatomical properties of South African growth Eucalyptus grandis.Appita 27(3):171-178.nTurvey, N. D., and P. J. Smethurst. 1985. Variations in wood density of Pinus radiata D. Don across soil types. Aust. For. Res. 15:43-49.nVilleneuve, M., E. K. Morgenstern, and L. P. Sebastian. 1987. Estimation of wood density in family tests of jack pine and black spruce using the Pilodyn tester. Can. J. For. Res. 17:1147-1149.nWalker, N. K., and R. S. Dodd. 1988. Calculation of wood density variation from X-ray densi-tometer data. Wood Fiber Sci. 20(1):35-43.nWilkes, J. 1988. Variation in wood density of Pinus radiata in New South Wales, Australia. Can. J. For. Res. 19:289-294.nWinistorfer, P. M., W. C. Davis, and W. W. Moschler. 1986. A direct scanning densitometer to measure density profiles in wood composite products. For. Prod. J. 36(11/12):82-86.n
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
