Estudo comparativo da massa específica aparente e retratibilidade da madeira de pau-Brasil (Caesalpinia echinata Lam.) Nativa e de reflorestamento

Abstract

Among physical properties of the wood, specific gravity and shrinkage are the most important characteristics to evaluate the wood quality and indication to several uses. Apparent specific gravity or density is an important physical characteristic that is related with shrinkage and others characteristics asthe mechanical and anatomical properties of the wood. Shrinkage is also an important characteristic because it determines as wood dimensional stability which is an important property for several uses in which wood should not present excessive contraction when being used. Thus, the objective of this study was to compare the specific gravity and shrinkage of Pernambuco wood (Caesalpinia echinata) from natural areas and reforestation at the ages of 10, 15, 20, 25 and 30 years. This study followed the Brazilian Method 26/1940 of Brazilian Associations of Technical Standard. The results indicate that there was variation in the apparent specific gravity and dry density atthe different ages with the highest value found for the wood at 30thirty years of age which was similar to the ones found for samples of native wood. The wood shrinkage also presented variation in function of the age but it did do not show differences in relation to native wood.