DENDROMETRIC AND CHEMICAL TRAITS AND BASIC DENSITY WOOD OF Eucalyptus grandis X Eucalyptus urophylla HYBRIDS

Abstract

O presente trabalho avaliou caracter\uedsticas dendrom\ue9tricas, qu\uedmicas e a densidade b\ue1sica da madeira de cinco h\uedbridos de Eucalyptus grandis x Eucalyptus urophylla , com 2,25 anos de idade. O experimento foi implantando no espa\ue7amento 3,5 x 2 m, com 35 repeti\ue7\uf5es e parcelas de uma planta. Quatro repeti\ue7\uf5es do experimento foram cortadas avaliando-se o di\ue2metro a altura do peito (DAP, a 1,3 m do solo), altura total e comercial, biomassa seca de folhas, galhos, madeira e casca, volume com e sem casca e volume de casca. Das \ue1rvores abatidas foram retirados discos de 5 cm de espessura no DAP e a 0 (base), 25, 50, 75 e 100% da altura comercial, para determina\ue7\ue3o da densidade b\ue1sica e caracteriza\ue7\ue3o qu\uedmica da madeira. Os dados foram submetidos \ue0 an\ue1lise de vari\ue2ncia e compara\ue7\ue3o de m\ue9dias pelo teste de Tukey a 5% de probabilidade. Os clones de Eucalyptus grandis x Eucalyptus urophylla diferiram quanto ao volume e biomassa com destaque para o C5 com valores superiores aos demais clones. A densidade b\ue1sica da madeira foi maior na base da \ue1rvore; nas demais posi\ue7\uf5es de amostragem, os valores de densidade foram semelhantes entre si; dentre os clones, o C5 apresentou densidade b\ue1sica da madeira superior ao C3 e ao C4, assim como o C2 superou o C3. As caracter\uedsticas qu\uedmicas da madeira foram semelhantes entre os clones e, apesar da avalia\ue7\ue3o ter sido realizada em plantas jovens, os clones demonstraram bom potencial em Jaboticabal - SP.The present study evaluated the dendrometric, chemical and basic density wood from five hybrids of Eucalyptus grandis x Eucalyptus urophylla at 2.25 years old. The experiment was implemented in 3.5 x 2 meters spacing, with 35 replicates of a single tree. Four replicates were harvester, we evaluated the diameter at breast height (DBH, 1.3 m above the ground), total and commercial height, biomass of leaves, branches, wood and bark, volume with and no bark and volume of bark. Besides it was obtained discs at 0, 25, 50, 75 e 100% of commercial height and at DBH for the determination of wood density and chemical characterization of wood. Data were subjected to analysis of variance and comparison of means by Tukey\u2019s test at 5 % probability. Clones of Eucalyptus grandis x Eucalyptus urophylla exhibited different growth highlighting the C5 with greater volumetric and biomass. The basic density wood is higher when assessed at base of tree, but it was verified similar values in other positions of the stem. Among the clones, the basic density wood of C5 is higher than C3 and C4 and C2 is higher than C3. The chemicals wood characteristics were similar among clones of Eucalyptus grandis x Eucalyptus urophylla. Despite the evaluation have been performed on young plants, 2.25 years old, the clones have demonstrated satisfactory potential in Jaboticabal, SP