Age, assortment and the storage time effect on the wood green density of Pinus taeda L.

Abstract

Green density knowledge is essential in the commercialization and industry supply, enabling conversion between wood volume and mass units. Thus, study objective was evaluated influence of the wood age, its dimensions and storage time in the Pinus taeda L. green density variation. To this, were studied logs with thin tip diameters between 8-18 cm (S1) and 18-24 cm (S2), aged 9 years. In addition to these, two others assortments were also analyzed for 21 year-old logs, 24-35 cm (S3) and over 35 cm (S4). Wood green density was determined by log diameter measurements and weighing at the harvesting time and on six other occasions, at 7, 14, 21, 28, 60 and 90 storage days in the field. Age, assortment and storage time effect were verified by general linear model (p<0.05). Subsequently, equations to green density estimating were adjusted in function of the wood basic density and log average diameter. Results showed that all factors considered had significant effect in wood green density. Older wood presented higher values for this variable and, within each age, wood green density increased as the log diameters decreased. Storage time had influence only S1 and S2 assortments green density at both ages. Adjusted equations showed satisfactory results to green wood density prediction. Thus, we concluded that factors studied must be considered in sampling process to wood green density determination, being possible use variables easily obteined, such as log average diameters to estimate this variable with satisfactory precision.

Keywords:
Conversion factor; Field storage; Wood density; Wood moisture