Shoot structure, leaf area index and productivity of evergreen conifer stands

For 12 conifer species, the maximum ratio of shoot to leaf silhouette area of shade-acclimated shoots was found to vary from 0.50 to 0.99. Maximum leaf area index (leaf area per unit ground area) of conifer stands varied from 3.5 to 20, and maximum mean annual increment varied by a factor of 2. Significant correlations were found between leaf silhouette area ratio of shade-acclimated shoots and the maximum leaf area index (R(2) = 0.84) and the maximum mean annual increment (R(2) = 0.93). These results support a hypothesis that species to species differences in the morphology of shade-adapted shoots strongly affect both the development of leaf area and the productivity of stands of evergreen conifers.