Reconstructed development of stem production and foliage mass and its vertical distribution in Japanese larch.

Hypotheses of independence with time in (1) height growth rate, (2) crown length, (3) total foliage mass, and (4) vertical profile of foliage mass density within a crown following canopy closure were tested with two codominant trees in a 15-year-old Japanese larch (Larix kaempferi (Lamb.) Carr.) plantation by means of a combined method consisting of detailed stem analysis (to reconstruct development of stem growth over time), knot dissection (to identify time of branch mortality), and a stem diameter versus cumulative foliage mass relationship at a given stem location. I failed to reject all hypotheses at the 5% significance level. All parameters converged to constant values after canopy closure. Foliage efficiency for stem volume density production also assumed a constant value. Vertical profiles of the foliage mass density did not change after crown closure; however, the profile for one tree showed a more heterogeneous distribution because of the presence of large branches. Implications of these results for the profile diagram model of tree growth (Chiba et al. 1988, Osawa et al. 1990) are discussed.