'Composicao Revista de Ciencias Sociais da Universidade Federal de Mato Grosso do Sul'
Abstract
The extractives are organic constituents present in small quantities in the wood, but affects various characteristics such as color, smell, specific gravity and durability. The extractive content may vary within the tree, however for Amazon woods this knowledge is little reported. The present study reports the variation of extractive content in radial direction of Alexa grandiflora Ducke wood from the Tapajos National Forest. The samples were collected from discs of three trees in five different positions of each disc in the radial direction. The extraction was conducted in cold-water, hot-water and ethanol/toluene solvent. The amount of extractives differ between positions. The extractives content decrease in radial direction, with a higher occurrence near the pith, followed by the heartwood and in less quantity in the sapwood
