Abstract:
With increasing private sector investments in commercial forestry, it is apparent that plantation
forestry in Sri Lanka is moving in the direction of managing fast growing timber species for shorter
rotations. However, there’s a perceptionthat accelerated growth rates induced by improved forest
management practices can result in inferior wood quality. This study tested this perceptionby studying
the effect of growth rate on the specific gravity, as a proxy for wood quality, of three alternative timber
species grown in Sri Lanka; Swietenia macrophylla, Khaya senegalensis and Paulownia fortunei.
Specific gravity remained more or less uniform from pith to bark regardless of the fluctuation of ring
width in K. senegalensis while S. macrophylla exhibited a slight increase in specific gravity from pith to
bark. This increasing trend was more prominent in P. fortunei. Results revealed growth rates represented
by ring width showed poor correlations with specific gravity in both S. macrophylla, and K.
senegalensis. Although P. fortunei showed a statistically significant positive correlation, regression
analysis indicated a poor relationship between growth rate and specific gravity. Hence it is unlikely that
wood specific gravity of the studied species to be influenced by accelerated growth rates.
