Variation in Shrinkage Properties of Second-Growth Baldcypress and Tupelo-Gum


  • Elvin T. Choong
  • Peter J. Fogg
  • Carolyn B. Pollock


Baldcypress, tupelo-gum, shrinkage, specific gravity, tree height, wood-type, radial position


Trees of baldcypress and tupelo-gum aged from 55 to 75 years, growing in a naturally regenerated stand in the Atchafalaya Basin in south Louisiana, were felled to provide samples for determination of shrinkage, specific gravity, and extractive content. Samples were taken from six heights and from three radial positions (=wood-types) along three radii. Differences among trees and among plots (which had different basal areas) were found for all measured variables. There were also variations in unextracted specific gravity with height in the tree and wood-type in baldcypress, and, except for specific gravity, with wood-type in tupelo-gum. After extraction, shrinkage effects of height and wood-type were reduced or disappeared. Specific gravity was generally lowest in the lower portion of the stem and in the outerwood. Correlation of shrinkage with specific gravity was highest in the outerwood, and extractive content was correlated with shrinkage in tupelo-gum but not in baldcypress.


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