Mechanical Properties of Small Clear Wood Specimens of Pinus patula Planted in Malawi


Pinus patula is one of the major exotic species grown in Malawi mainly for saw-timber production. It is native to Mexico. Little has been reported about the mechanical properties of the wood. The objective of this study was to investigate the mechanical properties of Pinus patula in more detail, in order to provide a basis for utilizing this resource. The mechanical properties of small clear wood specimens of Pinus patula were evaluated using 40 cm logs from 1, 3, 5, 7 and 9 m above the ground. Small clear wood specimens were selected and subjected to a bending test in accordance with Japan Industrial Standards (JIS) air-dry conditions. The growth rate did not affect the mechanical properties measured. There were significant correlations at 1% level between air-dry density and Modulus Of Elasticity (MOE) (R = 0.85) and between air-dry density and Modulus Of Rupture (MOR) (R = 0.83). There was also a significant correlation between MOE and MOR at 1% level (R = 0.90). At about 12% moisture content, the tested five Pinus patula families have average MOR and MOE of 105.17 MPa and 10.93 GPa, respectively.

Share and Cite:

Kamala, F. , Sakagami, H. & Matsumura, J. (2014). Mechanical Properties of Small Clear Wood Specimens of Pinus patula Planted in Malawi. Open Journal of Forestry, 4, 8-13. doi: 10.4236/ojf.2014.41002.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Anon (1947). Annual report. Pretoria: Department of Forestry.
[2] Anon (1980). Estudio de las propiedades fisicas y mecanicas de las maderas de cipres (Cupressus lusitanica Mill.) y pino patula (Pinus patula) procedente de la cuenca de Piedras Blancas. Medellin: Laboratorio de Productos Forestales, Universidad Nacional.
[3] Bier, H. (1983). The strength properties of small clear specimens of New Zealand grown timber. Bulletin No. 41, Rotorua: Forest Research Institute.
[4] Craib, I. J. (1939). Thinning, pruning and management studies on the main exotic conifers grown in South Africa. Science Bulletin No. 196, Pretoria: Department of Agriculture and Forestry.
[5] Deresse, T. (1998). The influence of age and growth rate on selected properties of Maine-grown red pine. Ph.D. Thesis, Orono, ME: University of Maine.
[6] Forestry and Forest Products Research Institute (FFPRI) (1975). The properties of tropical woods, 21: Evaluation of the wood properties and wood processing suitabilities of timbers from Southeast Asia and the Pacific regions. Bulletin of the Government Forest Experimental Station, 277, 87-130.
[7] Han, Y. (1995). The site and age effects on the selected physical and mechanical properties of red maple in Maine. Ph.D. Thesis, Orono, ME: University of Maine.
[8] Kamala, F.D., Sakagami, H., Oda, K., & Matsumura, J. (2013). Wood density and growth ring structure of Pinus patula planted in malawi, Africa. IAWA Journal, 34, 61-70.
[9] Ordonez, V., Barcenas, G., & Quiroz, A. (1989). Caracteristicas fisicomecanicas de lamadera de diez especies de San Pablo Macuilitanguis, Oaxaca. Madera y Su Uso, 21, 30p.
[10] Otto, K. P., & Van Vuren, W. F. J. (1976). The mechanical properties of timber with particular reference to those grown in the Republic of South Africa. Bulletin, Pretoria: Department of Forestry.
[11] Paterson, D. N., & Campbell, P. A. (1970). Strength variations and correlations in East African exotic pines and their effect on engineering properties. East African Agricultural and Forestry Journal, 35, 7-19.
[12] Perem, E. (1958). Effect of compression wood on mechanical properties of white spruce and red pine. Forest Products Journal, 8, 235240.
[13] SANS 10163 (2003). South African national standard. The structural use of timber—Part 1: Limit-states design. Edition 2.3.
[14] Shepard, R. K., & Shottafer, J. E. (1992). Specific gravity and mechanical property—Age relationships in red pine. Forest Products Journal, 42, 60-66.
[15] Shmulsky, R., & Jones, P. D. (2011). Forest products and wood science, an introduction (6th ed.). West Sussex: Wiley Blackwell.
[16] Shottafer, J. E., Kutscha, N. P., & Hale, R. A. (1972). Properties of plantation grown red pine related to its utilization. Technical Bulletin, Orono, ME: Life Sciences and Agriculture Experiment Station, University of Maine at Orono.
[17] Stanger, T. K. (2003). Variation and genetic control of wood properties in the juvenile core of Pinus patula grown in South Africa. Ph.D. Thesis, Raleigh, NC: Department of forestry, Graduate Faculty of North Carolina State University.
[18] Wright, J. A. (1994). Utilization of Pinus patula: An annotated bibliography. O.F.I. Occasional Papers No. 45, Oxford: Oxford Forestry Institute, Department of Plant Sciences, University of Oxford.
[19] Wolcott, M. P. (1985). Age and growth rate relationships of selected mechanical properties in red spruce. M.S. Thesis, Orono, ME: University of Maine.
[20] Zhang, S. Y. (1995). Effect of growth rate on wood specific gravity and selected mechanical properties in individual species from distinct wood categories. Wood Science and Technology, 29, 451-465.
[21] Zhang, S. Y. (1997). Wood specific gravity-mechanical property relationship at species level. Wood Science and Technology, 31, 181-191.

Copyright © 2024 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.