, 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
    • Department of ForestryUniversity of Florida
  • James N. Long
    • Department of Forest Resources and Ecology CenterUtah State University
  • Frederick W. Smith
    • Department of Forest and Wood SciencesCollege of Forestry and Natural Resources, Colorado State University

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