Technical Note: The Suitability of Young Fast-Grown Radiata Pine Clones for Conversion into Vineyard Trellis Posts

Authors

  • Philip D. Evans
  • Chris Borough
  • Robin Wingate-Hill
  • Ross B. Cunningham

Abstract

In this note, we test the hypothesis that vineyard trellis posts of the required size and strength properties can be produced from young radiata pine trees obtained from clonal plantations established using a dense stocking of physiologically aged cuttings selected for fast growth, good straightness, above-average juvenile wood density, and fine multinodal branching. Radiata pine trees from four different clones were all large enough to be converted into vineyard posts when they were 6 yr old. Posts made from the fastest growing clone had below-average wood density and a high grain angle and were significantly weaker than commercial posts made from 14-yr-old thinnings. Another clone, however, produced posts whose average breaking load and modulus of rupture were only 8.6 and 9.2% lower, respectively, than those of commercial posts. Posts from this clone had a low grain angle and above-average wood density as well as fine multinodal branching. We conclude that the use of selected radiata pine clones for the manufacture of vineyard posts shows promise as an alternative to the production of posts from thinnings and suggest how the strength properties of posts from clonal radiata pine trees might be further improved.

References

Baltunis BS, Wu HX, Powell MB (2007) Inheritance of density, microfibril angle, and modulus of elasticity in juvenile wood of Pinus radiata at two locations in Australia. Can J For Res 37(11):2164-2174.nBamber RK, Burley J (1983) The wood properties of radiata pine, 1st ed. Commonwealth Agricultural Bureaux, Slough. 84 pp.nBurdon RD, Harris JM (1973) Wood density in radiata pine clones on four different sites. N Z J For Sci 3(3):286-303.nEvans PD, Beutel P, Cunningham RB, Donnelly CF (1994) Fire resistance of preservative treated slash pine fence posts. Forest Prod J 44(9):37-39.nMcCarthy KJ, Cookson LJ, Mollah M, Norton J, Hann J (2005) The suitability of plantation thinnings as vineyard posts. FWPRDC (Australia) Rept. No. PN02.3900, 189 pp.nMollah M, Smith J, McCarthy K, Cookson L (2004) Alternatives to CCA-treated Pinus radiata as vineyard posts. The Internat. Res. Group on Wood Preservation Doc. IRG/WP 04-50212, 14 pp.nMollah MR, Aust MIE, Hayes RJ, Reynolds J (1995) Breaking force of treated pine posts for trellising. J Soc Eng Agric 24(2):3-9.nStandards Australia (2000) Specification for preservative treatment. Part 1, Sawn and round timber, AS 1604.1-2000. Standards Association of Australia, Sydney, 44 pp.nWaghorn MJ, Mason EG, Watt MS (2007) Influence of initial stand density and genotype on longitudinal variation in modulus of elasticity for 17-year-old Pinus radiata.For Ecol Mgmt 252(1-3):67-72.n

Downloads

Published

2010-04-05

Issue

Section

Research Contributions