, Volume 2, Issue 2, pp 104–109

Bias in leaf area — sapwood area ratios and its impact on growth analysis in Pinus contorta

  • Thomas J. Dean
  • James N. Long
  • Frederick W. Smith

DOI: 10.1007/BF00196756

Cite this article as:
Dean, T.J., Long, J.N. & Smith, F.W. Trees (1988) 2: 104. doi:10.1007/BF00196756


Two alternative estimators of individual tree leaf area (A1) area are used to derive estimates of leaf-area index (L) for 40 plots in Pinus contorta Dougl. stands. One estimator of A1 is based on the common assumption of a constant ratio between A1 and sapwood cross-sectional area at breast height (As). The second estimator of A1 accounts for tree-to-tree variation in the relation between A1 and As. The apparent relationship between stand growth and leaf-area index is strongly dependent on the way leaf area is estimated. When L is derived from a constant A1∶As ratio, stand growth appears to be strongly correlated with L. However, when L is based on estmates of A1 that account for tree-to-tree variation in the A1 — As relation, stand growth is seen to be only weakly related to L. Stand structure, quantified as percent live-crown, accounts for a great deal of the observed variation in leaf-area efficiency. These contrasting relationships illustrate the importance of unbiased estimates of L in interpreting the link between stand-level processes and leaf area.

Key words

Leaf areaSapwood cross-sectional areaProductionLeaf-area efficiency

Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • Thomas J. Dean
    • 1
  • James N. Long
    • 2
  • Frederick W. Smith
    • 3
  1. 1.Department of ForestryUniversity of FloridaGainesvilleUSA
  2. 2.Department of Forest Resources and Ecology CenterUtah State UniversityLoganUSA
  3. 3.Department of Forest and Wood SciencesCollege of Forestry and Natural Resources, Colorado State UniversityFort CollinsUSA