Abstract:
Juvenile Pennantia corymbosa plants are divaricate in form. They display periodic growth patterns along axes; there are stem sections with long internodes, stem angles which deviate from 180�, and expanded lateral shoots, between which are stem sections with short internodes which lack lateral shoots and stem angles. There is a strong positional association between long internodes, stem angles, and lateral outgrowth. Plants have three shoot types - short shoots, non-sylleptic long shoots, and sylleptic long shoots - that differ in parental control of elongation. The ratios of leaf: total dry-weight biomass of juvenile P. corymbosa branches are similar to ratios from North American deciduous woody shrubs but lower than ratios from evergreen shrubs. Juvenile P. corymbosa plants display features such as phenotypic plasticity, a diversity of shoot types, and wide branch angles which may enhance light capture. However, the costs for light capture associated with a low contribution of biomass to foliage may be high.