Biomass and Coppicing Ability of Genetically Improved Calliandra calothyrsus for Wood-Energy with Different Spacing

Abstract

Beside wood quality, biomass and ability to coppice of fast-growing woody species for renewable energy are two essential indicators. Appropriate spacing among individual plant is therefore required to get the best harvest. This study is observing biomass, branching and coppicing ability of Calliandra calothyrsus at different spacings. Initial experimental plots were using 5 blocks of 16 individuals at spacings of 0.5x1; 1x1; 0.5x2; 1x2 and 2x2m and assessed at 6 months old around reproductive stage. Due to no significant differences, two spacing plots of 2x1 and 1x1m are compared for biomass and wood dimension assessment from 14 individuals per block replicated into 4 blocks after 3 years. Coppicing ability was counted after 2 months of felling. The results indicated that diameter has positive correlation with number of initial branches as well as number of coppices. Specific gravity of wood is also increasing with diameter. Between the two types of spacing, the first wood production is better for 1x1m than 1x2m with 76.3 ton/ha (152 m3/ha) for 1x1m and 72 ton/ha (144 m3/ha) for 1x2m. This indicates a better production than the predicted MAI from the breeding. Specific gravity is recorded to be better at more spaciuos distance.