Evaluation of wood properties of four ages of Cedrela odorata trees growing in agroforestry systems with Theobroma cacao in Costa Rica

摘要

The present work studies the morphological, physical, mechanical and chemical properties, decay resistance, preservation and workability of Cedrela odorata wood from trees growing in agroforestry systems with Theobroma cacao at four ages (4-, 5-, 6- and 7-years-old) in Costa Rica. It was found that the morphological properties (heartwood, pith and bark), together with the physical properties (specific gravity, green density, shrinkage and green moisture content) presented few differences at the four ages. The wood from 4-years-old trees was the only exception, showing less resistance in compression, flexion and lateral hardness. The content of lignin, carbon, and extractives in hot water were not affected among the different ages, contrary to the rest of chemical properties. In relation to decay resistance in accelerated tests with the fungus Trametes versicolor, the wood is classified as highly resistant, while with the fungus Lencites acuta it is classified as moderately resistant. As concerns properties related to industrialization, it was found that the wood can be preserved through vacuum-pressure methods obtaining similar results as those from other plantation timbers. As for workability tests, the wood from the 4-years-old trees show acceptable to very poor performance, differing from trees from the other ages.