Calculation of Wood Density Variation From X-ray Densitometer Data


  • Nancy K. Walker
  • Richard S. Dodd


X-ray densitometry, wood density, density variation, Pinus radiata


A method is proposed for quantifying the variation in wood density as recorded by X-ray densitometry. This method uses the sum of the squared deviations from the mean density, and so approximates a true statistical variance. This gives greater meaning to variation than has previously been described. The density variation can be computed for a single growth ring, or several growth rings. The calculations are shown using data from 11-year-old Pinus radiata trees.


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