Glenn Galloway

Foliage biomass - sapwood (area and volume) relationships of Tectona grandis L.F. and Gmelina arborea Roxb.: silvicultural implications

Abstract We developed foliage biomass to sapwood (area and volume) relationships for Tectona grandis L.F. and Gmelina arborea Roxb. growing in the Guanacaste province of Costa Rica. Strong linear relationships confirmed the applicability of Shinozakis pipe model theory to both of these fast-growing, tropical species. The linear models include data from 80 (40 per species) dominant, codominant, and suppressed trees that had been growing in un-, late and early thinned plantations and fence-row plantings. Results are applicable across a wide range of foliage biomass values. The relationships between foliage biomass and sapwood area and volume of the previous years growth ring were also analyzed and were found to be highly significant for T. grandis. Findings confirm that silvicultural regimes of these species must allow individual trees to augment foliage biomass from an early age if sustained rapid diameter growth is desired.