Populus deltoides clone ‘Australian 129-60’: density axial variation and predictive model for whole tree density

Abstract

The aims were to determine the axial variation pattern for wood density of Populus deltoides clone ‘Australian 129-60’ and to develop a predictive model for whole tree density from density at one sample height. Eleven ten-year-old trees from three diametric classes were sampled in Buenos Aires Province, Argentine. Disks were taken at seven sampling heights (0.5 m; 0.7 m; 1.0 m; 2.2 m; 6.6 m; 11.0 m and 15.4 m). Density and weighted density were determined at 15% of moisture content. An analysis of variance was carried out for sampling heights and diametric classes. The relationship between whole tree density and predictive parameters, density at 1.0 m height and Diameter at breast height (DBH), was quantified using linear and non linear regression analyses. Clone mean density was 458 ± 35 kg m^–3 and weighted density was 470 ± 14 kg m^–3. Density axial variation shows significantly increasing values from the lower sampling height to the top. Density taken at breast height, approximately (1.0 m), underestimates (11%) the weighted density of whole tree. It is feasible to produce high diameters poplars and to obtain major wood density at the same time. It is possible to fit models to estimate the mean weighted density of whole tree based on density at breast height approximately, with linear regression analysis.