The Influence of Tree Spacing in Heartwood Content in <i>Eucalyptus Globulus</i> Labill


  • Jorge Gominho
  • Helena Pereira


<i>Eucalyptus globulus</i> Labill, heartwood, sapwood, spacing, variability


Heartwood content was studied in 27 Eucalyptus globulus Labill. trees with spacings 3 x 3, 3 x 2, and 2 x 1 (m x m), with 9 years, from a 1st rotation spacing trial. The height attained by heartwood increased with total tree height independently of spacing, and reached on average 45%, 59%, and 62% of total height, respectively, for spacings 2 x 1, 3 x 2, and 3 x 3. In all the spacings, the heartwood radius decreased gradually along tree height, and the radial thickness of sapwood remained practically constant at approximately 16 mm in the lower part of the stem (<35% of height), and increased upwards. Sapwood thickness did not depend on tree growth rate, remaining constant for all tree diameters. Heartwood diameter increased with tree diameter, with larger trees showing more heartwood regardless of spacing. Sapwood thickness was not correlated with tree radius, but sapwood area showed a good linear regression. The proportion of heartwood volume increased with spacing from 20.3% to 41.1% of tree volume, respectively for 2 x 1 and 3 x 3 spacings.


Bamber R. K. 1976. Heartwood function and formation. Wood Sci. Technol.10:1-8nBamber R. K. 1985. The wood anatomy of eucalyptus and papermaking. Appita.38(3):210-216.nBamber R. K. and K. Fukazawa. 1985. Sapwood and heartwood. A review. Forestry Abstr.46:567-580nCliment J., M. R. Chambel, L. Gil, and J. Pardos. 2003. Vertical heartwood variation patterns and prediction of heartwood volume in Pinus canariensis Sm. For. Ecol. Mgmt. 174:203-211.nDelgado, J., and M. Tomé. 1997. Aboveground biomass allocations in young Eucalyptus globulus planted at different spacing. Pages 125-129 in EMBRAPA eds. Proc. IUFRO Conference on Silviculture and Improvement of Eucalypt. Centro Nacional de Pesquisas Florestais, Colombo.nFao. 2001. Global forest resources assessment. Main report.'>, J., and H. Pereira. 2000. Variability of heartwood content in plantation-grown Eucalyptus globulus Labill. Wood Fiber Sci.32(2):189-195nGominho, J., J. Figueira, J. Rodrigues, and H. Pereira. 2001. Within-tree variation of heartwood, extractives and wood spacing in the eucalypt hybrid urograndis (Eucalyptus grandis x E. urophylla). Wood Fiber Sci.. 33(1):3-8nHiggins, H. G. 1984. Pulp and paper. Pages 290-316 in W. E. Hillis and A. G. Brown, eds. Eucalyptus for wood production. CSIRO/Academic Press Melbourne, Australia.nHillis, W. E. 1962. Wood extractives and their significance to the pulp and paper industries. Academic Press, New York, NY. 513 pp.nHillis, W. E. 1972. Properties of eucalypt woods of importance to the pulp and paper industries. Appita26:113-122.nHillis, W. E. 1987. Heartwood and tree exudates. Springer-Verlag, Berlin. 268 pp.nKärkkäinen, M. 1972. On the proportion of heartwood in Norway spruce and Scots pine. Silva Fenn.6(3):193-208nMontgomery, D. C. 1991. Design and analysis of experiments. 3rd edition. John Wiley & Sons. New York, NY. 704 pp.nMörling, T., and E. Valinger. 1999. Effects of fertilization and thinning on heartwood area, sapwood area and growth in Scots Pine. Scand. J. For. Res.14:462-469.nPereira, H., F. Lopes, and J. Graça. 1996. The evaluation of the quality of cork planks by image analysis, Holzforschung50:11-15.nPinto, I., H. Pereira, and A. Usenius. 2004. Heartwood and sapwood development within Maritime pine (Pinus pinaster Ait.) stems. Trees18:284-294.nPurkayastha, S. K., S. P. Agrawal, R. D. Tandon, and L. Chauham. 1980. Variation in the porportion of heartwood in Eucalyptus tereticornis. Indian For.106:466-473.nSoares, A. P. 1995. Competição intra-específica em povoamentos de Eucalyptus globulus Labill. Uma aplicação a índices de competição dependentes da distância. Ms. D. Thesis, Instituto Superior de Agronomia, Lisboa, Portugal.nSoares, A. P. 1999. Modelação do crescimento da árvore em eucaliptais em 1a rotação localizados nas regiões norte e centro litoral. Doctoral thesis, Instituto Superior de Agronomia, Lisboa, Portugal.nTaylor, A. M., B. L. Gartner, and J. J. Morrell. 2002. Heartwood formation and natural durability - A review. Wood Fiber Sci.34(4):587-611.nTomé, M., F. Ribeiro, P. Soares, H. Pereira, I. Miranda, and J. P. Pina. 1995. Effect of spacing on Eucalyptus globulus fibre yield and quality. Pages 60-63 in B. M. Potts, N. Borralho, J. B. Reid, R. N. Crommer, W. N. Tibbits, and C. A. Raymond eds. Eucalypt plantations: Improving fiber yield and quality. CRCTHF - IUFRO, Hobart, Australia.nWilkes, J. 1991. Heartwood development and its relationship to growth in Pinus radiata. Wood Sci. Technol.25:85-90.nWilkins, A. P. 1991. Sapwood, heartwood, and bark thickness of silviculturaly treated Eucalyptus grandis. Wood Sci. Technol.25:415-423.nWomeldorff, F. M. 1965. Separation of heartwood from sapwood pulp chips by flotation methods. Forest Prod. J.15(9):407-408.n






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