Clonal Variation In The Quality of Radiata Pine Random Width Boards
Keywords:
Pinus radiata, clones, defect frequency, DBH, internode, random width boardsAbstract
This clonal study was undertaken to analyze clonal variation in the quality of random width boards, and to document broad sense heritabilities of the board quality and the associated tree variables in radiata pine (Pinus radiata D. Don). Two individual trees from each often clones were selected based on a wide range of clone mean values for diameter at breast height (DBH), internode index, branch index, and outerwood basic density.
Several defect types and frequencies showed differences between clones; variation between clones was greater for defect frequencies than for defect areas. Also differences between clones were greater for boards from unpruned logs than from pruned logs. Knot frequency was far higher in boards coming from the clones with shorter internodes, while knot area per m2 did not vary significantly between clones. Internode length appeared to be highly heritable. The blemish area per m2 from pruned logs was highly variable between clones. Causes and exact configuration of this latter defect are largely unknown and unpredictable but appear to be associated with pruning.
Differences were observed in the grade distributions between clones. For all log types, the best performing clone was a large DBH clone with the longest internodes, while a small DBH clone with the shortest internode was the worst. These results show that defect frequency and grades in appearance lumber and associated tree characteristics show high broad sense heritability. This suggests that the grades and the value of these products can be predicted, particularly from tree internode index. A breeding program for long internode radiata pine, started in 1970, has already shown that this trait responds well to selection and breeding.
References
Dunlop, J. 1995. Permanent sample plot system user manual. FRI Bull. No. 187. Forest Research Institute, Rotorua, New Zealand.nGatchell, C. J., J. K. Wiedenbeck, and E. S. Walker. 1993. A red oak data bank for computer simulations of secondary processing. Forest Prod. J. 43(6):38-42.nGazo, R., and P. H. Steele. 1995. Rough mill analysis and modeling (RAM). Forest Prod. J. 45(4):51-53.nGazo, R., R. Beauregard, and S. Mitchell. 1998. Development of radiata pine random width boards database and incidence of defects. N. Z. J. Forest Sci. 33 pp. (in press).nHarding, O. V., P. H. Steele, and K. Nordin. 1993. Description of defects by type for six grades of red oak lumber. Forest Prod. J. 43(6):45-50.nKininmonth, J. A., and L. J. Whiteside. 1991. Properties and uses of New Zealand radiata pine, vol. 1. Wood properties. J. A. Kininmonth and L. J. Whiteside, eds. Forest Research Institute, Rotorua, New Zealand.nNew Zealand Forest Industries. 1996. Directory and yearbook. Ed. by New Zealand Forest Industries Mag, vol. 27, no. I. P.O. Box 5544, Aukland, New Zealand.nNew Zealand Ministry Of Forestry. 1994. Producing random width lumber for the U.S. market. J. Stulen, ed. NZ MoF, Box 1340, Rotorua, New Zealand.nSteele, P. H., and R. Gazo. 1995. A procedure for determining the benefits of sorting lumber prior to rough mill processing. Forest Prod. J. 45(6):51-55.nSteele, P. H., T. E. G. Harless, F. G. Wagner, L. Kumar, and F. W. Taylor. 1994. Increased lumber value from optimum orientation of internal defects with respect to sawing pattern in hardwood sawlogs. Forest Prod. J. 44(3):69-72.nTodoroki, C. L. 1995. Grading random width lumber by computer. N. Z. J. Forestry Sci. 25(3):367-378.nWestern Wood Products Association. 1991. Western Lumber Grading Rules 91, chap. 11. Portland, OR.nWhiteside, I. D., and B. R. Manley. 1987. Radiata pine resource description by log-grade specifications. Pages 27-38 in Proc. Conversion Planning Conf., 8-11 April 1986. FRI Bull. 128. Rotorua, New Zealand.n
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
