CROWN DEVELOPMENT IN RED PINE STANDS .2. RELATIONSHIPS WITH STEM GROWTH

The development of red pine (Pinus resinosa Ait.) stands originating under different initial spacings was examined using three measures of growth efficiency that are similar in concept to relative growth rate: diameter at breast height (DBH) increment / crown width, DBH increment / crown projection, and DBH increment / foliage biomass. These three measures of efficiency decreased with increasing DBH in the absence of severe competition and increased with increasing DBH under severe competitive stress. This indicates that small trees occupied their aerial growing space better and utilized their foliage to produce stemwood more efficiently than large trees in the absence of competition, and that the effect of competition was to reverse this trend. Absolute and relative growth rates for DBH and the three measures of growth efficiency were related very significantly to absolute (e.g., crown width) and relative (e.g., crown width / crown length) measures of crown development.