Natural durability assessment of thermo-modified young wood of eucalyptus

  • Sofia Knapic
  • Joana Santos
  • José Santos
  • Helena Pereira
Keywords: Eucalyptus botryoides, Eucalyptus globulus, mechanical properties, shrinkage, termites, wood degradation


This study focuses on the effect on wood strength and natural durability of Eucalyptus globulus and Eucalyptus botryoides when subjected to heat treatments with low energy consumption. The objective was to improve the wood durability, without negatively impacting the strength properties. Six-year-old trees from Eucalyptus globulus and Eucalyptus botryoides were used.

The samples were heat treated for 4 h conditioned to very low oxygen availability. A field test for assessing the resistance to termites and fungal degradation was conducted according to EN 252:1989/AC1:1989 Inspections were made every six months for 3 years. All the samples of Eucalyptus globulus showed signs of termite and microorganisms attack, most showing extensive galleries. Eucalyptus botryoides wood showed no sign of termite attack and only few traces of microrganisms presence. The wood bending strength was smaller upon thermal treatment for both species, decreasing 3.8% and 4.8% for Eucalyptus globulus and Eucalyptus botryoides, respectively. Overall the results are promising regarding some common utilizations, mainly floor coverings, decks, doors and door and window frames, fences (only for Eucalyptus botryoides), decorative arbors and pergolas (only for Eucalyptus botryoides), but excluding structural beams for building roofs or bridges due to the fragility of the wood treated thermally towards impacts.


ARANGO, R.A.; GREEN III, F.; HINTZ, K.; LEBOW, P.K.; MILLER, R.B. 2006. Natural durability of tropical and native woods against termite damage by Reticulitermes flavipes (Kollar). International Biodeterioration & Biodegradation 57 (3): 146–150.

ARAÚJO, S.O.; VITAL, B.R.; OLIVEIRA, B.; CARNEIRO, A.C.O.; LOURENÇO, A.; PEREIRA, H. 2016. Physical and mechanical properties of heat treated wood from Aspidosperma populifolium, Dipteryx odorata and Mimosa scabrella. Maderas-Cienc Tecnol 18(1): 143-156.

ANTWI-BOASIAKO, C.; ALLOTEY , A. 2010. The effect of stake dimension on the field performance of two hardwoods with different durability classes. International Biodeterioration & Biodegradation 64: 267-273.

BATISTA, D.C.; NISGOSKI, S.; OLIVEIRA, J.T.S.; MUÑIZ, G.I.B.; PAES, J.B. 2016. Resistance of thermally modified Eucalyptus grandis W. Hill ex Maiden wood to deterioration by dry-wood termites (Cryptotermes sp.). Ciência Florestal 26 (2): 671-678.

BLOMBERG, J.; PERSSON, B.; BLOMBERG, A. 2005. Effects of semi-isostatic densification of wood on the variation in strength properties with density. Wood Science and Technology 39: 339–350.

BRISCHKE, C.; WELZBACHER, C.R.; RAPP, A.O.; AUGUSTA, U.; BRANDT, K. 2009. Comparative studies on the in-ground and above-ground durability of European oak heartwood (Quercus petraea Liebl. and Quercus robur L.). European Journal of Wood Products 67: 329-338.

BS 373.1957. Methods of Testing Small Clear Specimens of Timber.

CADEMARTORI, P.H.G.; MISSIO, A.L.; MATTOS, B.D.; GATTO, D.A. 2015. Effect of thermal treatments on technological properties of wood from two Eucalyptus species. Anais da Academia Brasileira de Ciências 87(1): 471-481.

CRUZ, H.; JONES, D.; NUNES, L. 2015. Wood. In Materials for Construction and Civil Engineering. M.C. Gonçalves, F. Margarido (eds.), Springer International Publishing Switzerland. Pp 557-583.

DOI, S.; KURIMOTO, Y.; OHMURA, W.; OHARA, S.; AOYAMA, M.; YOSHIMURA, T. 1999. effects of heat treatments of wood on the feeding behaviour of two subterranean termites. Holzforschung 53: 225-229.

DWIANTO, W.; TANAKA, F.; INOUE, M.; NORIMOTO, M. 1996. Crystallinity changes of wood by heat or steam treatment. Wood Research 83: 47-49.

ESTEVES, B.; NUNES, L.; DOMINGOS, I.; PEREIRA, H. 2014. Improvement of termite resistance, dimensional stability and mechanical properties of pine wood by paraffin impregnation. European Journal of Wood and Wood Products 72: 609-615.

ESTEVES, B.M.; DOMINGOS, I.J.; PEREIRA, H.M. 2007. Pine wood modification by heat treatment in air. BioResources 3(1): 1-5.

ESTEVES, B.M.; MARQUES, A.V.; DOMINGOS, I.; PEREIRA, H. 2008. Heat-induced colour changes of pine (Pinus pinaster) and eucalypt (Eucalyptus globulus) wood. Wood Science and Technology 42: 369–384.

ESTEVES, B.M.; PEREIRA, H.M. 2009. Wood modification by heat treatment: A review. BioResources 4 (1): 370–404.

EUROPEAN STANDARD EN 252.1989. Field test method for determining the relative protective effectiveness of wood preservatives in ground contact. Inspection and evaluation of the attack of stakes caused by microorganisms. CEN.

EUROPEAN STANDARD EN 408. 2003. Timber structures - Structural timber and glued laminated timber - Determination of some physical and mechanical properties.

EUROPEAN STANDARD EN 1910. 2000. Wood and parquet flooring and wood panelling and cladding – determination of dimensional stability. CEN.

GASCÓN-GARRIDO, P.; OLIVER-VILLANUEVA, J.V.; IBIZA-PALACIOS, M.S.; MILITZ, H.; MAI, C.; ADAMOPOULOS, S. 2013. Resistance of wood modified with different technologies against Mediterranean termites (Reticulitermes spp.). International Biodeterioration & Biodegradation 82: 13-16.

GRACE, J.K.; EWART, D.M.; TOME, C.H.M. 1996. Termite resistance of wood species grown in Hawaii. Solid Wood Products 46 (10): 57-60.

GULLER, B. 2012. Effects of heat treatment on density, dimensional stability and color of Pinus nigra wood. African Journal of Biotechnology 11 (9): 2204-2209.

GUNDUZ, G.; AYDEMIR, D.; KARAKAS, G. 2009. The effects of thermal treatment on the mechanical properties of wild Pear (Pyrus elaeagnifolia Pall.) wood and changes in physical properties. Materials & Design 30 (10): 4391-4395.

HADI, Y.S.; NURHAYATI, T.; JASNI, J.; YAMAMOTO, H.; KAMIYA, N. 2010. Smoked Wood as an Alternative for Wood Protection against Termites. Forest Products Journal 60 (6): 496-500.

HILL, C.A.S. 2006. Wood Modification: Chemical, Thermal and Other Processes. 1st ed. Chichester: John Wiley & Sons, 260.

HOMAN, W.J.; JORISSEN, A.J.M. 2004. Wood modification developments. Heron 49 (4): 361-386.

INOUE, M.; MORIMOTO, M.; TANAHASHI, M.; ROWELL, R. 1993. Steam or heat fixation or heat fixation of compressed wood. Wood and Fiber Science 25 (3): 224-235.

IPQ STANDARD. 1973. NP 616. Madeiras - Determinação da massa volúmica.

IPQ STANDARD. 1973. NP 619. Madeiras - Ensaio de flexão estática.

KAMKE, F.A.; SIZEMORE, H. 2008. Viscoelastic thermal compression of wood. US Patent: 7404422.

KIM, G.; YUN, K.; KIM, J. 1998. Effect of heat treatment on the decay resistance and the bending properties of radiata pine sapwood. Material und Organismen 32(2): 101-108.

KOCH, G.; PULS, J.; BAUCH, J. 2003. Topochemical characterisation of phenolic extractives in discoloured beechwood (Fagus sylvatica L.). Holzforschung 57 (4): 339–345.

KOLLMAN, F.F.P.; CÔTÉ JR, W.A. 1984. Principles of Wood Science and Technology. In: Solid Wood, vol. 1. Springer-Verlag OHG, Berlin, Heidelberg, New York/Tokyo.

KORKUT, R.; AKGÜ, M.; DÜNDAR, T. 2008. The effects of heat treatment on some technological properties of Scots pine (Pinus sylvestris L.) wood. Bioresource Technology 99: 1861-1868.

LESAR, B.; HUMAR, M.; KAMKE, F.A.; KUTNAR, A. 2013. Influence of the thermo-hydro-mechanical treatments of wood on the performance against wood-degrading fungi. Wood Science and Technology 47 (5): 977-992.

LESAR, B.; HUMAR, M. 2010. Use of wax emulsions for improvement of wood durability and sorption properties. European Journal of Wood and Wood Products 69: 231-238.

MANABENDRA, D.; SAIKIA, C.N.; BARUAH, K.K. 2002. Studies on thermal degradation and termite resistant properties of chemically modified wood. Bioresource Technology 84 (2): 151-157.

MANTANIS, G.; TERZI, E.; KARTAL, S.N.; PAPADOPOULOS, A.N. 2014. Evaluation of mold, decay and termite resistance of pine wood treated with zinc- and copper-based nanocompounds. International Biodeterioration & Biodegradation 90: 140-144.

MILITZ, H. 2002. Heat treatment of wood: European processes and their background, In: International Research Group Wood Pre. Section 4- Processes. NºIRG/WP. 02-40241.

NAVI, P.; GIRARDET, F. 2000. Effects of thermo-hydro-mechanical treatment on the structure and properties of wood. Holzforschung 54 (3): 287–293.

NEIVA, D.; FERNANDES, L.; ARAÚJO, S.; LOURENÇO, A.; GOMINHO, J.; SIMÕES, R.; PEREIRA, H. 2015. Chemical composition and kraft pulping potential of 12 eucalypt species. Industrial Crops and Products 66: 89–95.

NCUBE, E.; CHUNGU, D.; KAMDEM, D.P.; MUSAWA, K. 2012. Use of a short span field test to evaluate termite resistance of Eucalyptus grandis and Bobgunnia madagascariensis in a tropical environment. BioResources 7 (3): 4098-4108.

NGUYEN, C.T.; WAGENFÜHR, A.; PHUONG LE, X.; DAI, V.H.; BREMER, M.; FISCHER, S. 2012. The effects of thermal modification on the properties of two Vietnamese Bamboo species, part I: effects on physical properties. BioResources 7 (4): 5355-5366.

PAINE, D.T.; STEINBAUER, J.M.; LAWSSON, S.A. 2011. Native and exotic pests of Eucalyptus: a wordwilde perpective. Annual Review of Entomology 56: 181-201.

PALANTI, S.; SUSCO, D.; FEC,I E. 2010. Natural durability of eucalypt from Italian plantations against fungiand cerambicid Trichoferus holosericeus Rossi. European Journal of Wood and Wood Products 68: 59–62.

PERALTA R,.C.G.; MENEZES, E.B.; CARVALHO, A.G.; AGUIAR-MENEZES, E.L. 2004. Wood consumption rates of forest species by subterranean Termites (isoptera) under field conditions. Árvore 28: 283-289.

PESSOA, A.M.C.; BERTI-FILHO, E.; BRITO, J.O. 2006. Avaliação da madeira termorretificada de Eucalyptus grandis, submetida ao ataque de cupim de madeira seca, Cryptotermes brevis [Evaluation of the Eucalyptus grandis thermorectificated wood submitted to the drywood termite attack, Cryptotermes brevis]. Scientia Forestalis 72: 11-16.

PANSHIN, A.; DE ZEEW, C. 1980. Textbook of Wood Technology. Structure, Identification, Properties and Uses of the Commercial Woods of the United States and Canada. Fourth ed. McGraw-Hill, Inc, New York, USA.

ROCKWOOD D.L.; RUDIE A.W.; RALPH S.A.; ZHU J.Y.; WINANDY J.E. 2008. Energy product options for Eucalyptus species grown as short rotation woody corps. International Journal of Molecular Sciences 9 (8): 1361-1378.

SANTOS, J.A. 2000. Mechanical behaviour of Eucalyptus wood modified by heat. Wood Science and Technology 34 (1): 39-43.

SANTOS, J.A.; KNAPIC, S.; PEREIRA , H. 2016. Processo de modificação térmica da madeira em leito poroso inerte e de condicionamento mecânico. PT Patent request: 108505 (

SCHOLZ, G.; MILITZ, H.; GASCÓN-GARRIDO, P.; IBIZA-PALACIOS, M.S.; OLIVER-VILLANUEVA, J.V.; PETERS, B.C.; FITZGERALD, C.J. 2010. Improved termite resistance of wood by wax impregnation. International Biodeterioration & Biodegradation 64: 688-693.

SILVA, J.C.; OLIVEIRA, J.T.S.; XAVIER, B.A.; CASTRO, V.R. 2006. Variação da retratibilidade da madeira de Eucalyptus grandis Hill ex Maiden, em função da idade e posição radial no tronco [Influence of age and radial position the volumetric and linear shrinkage of Eucalyptus grandis Hill ex Maiden wood]. Árvore 30 (5): 803-810.

SPINELLI, R.; WARDB, S.M.; OWENDEC, P.M. 2009. A harvest and transport cost model for Eucalyptus spp. fast-growing short rotation plantations. Biomass & Bioenergy 33 (9): 1265 – 1270.

SUNDQVIST, B.; KARLSSON, O.; WESTERMARK, U. 2006. Determination of formic-acid and concentrations found during hydrothermal treatment of birch wood and its relation to colour, strength and hardness. Wood Science and Technology 40 (7): 549-561.

TAKAMURA, K. 2001. Effects of Termite Exclusion on Decay of Heavy and Light Hardwood in a Tropical Rain Forest of Peninsular Malaysia. Journal of Tropical Ecology 17 (4): 541-548.

TRADA. 1984. Timber Pests and Their Control. Timber Research and Development Association (TRADA). Executive Press Limited, Burnham. Bucks. England.

TJEERDSMA, B.F.; BOONSTRA, M.; PIZZI, A.; TEKELY, P.; MILITZ, H. 1998. Characterisation of thermally modified wood: molecular reasons for wood performance improvement. Holz als Roh-und Werkstoff 56 (3): 149-153.

TSUNODA, K. 1990. The Natural Resistance of Tropical Woods against Biodeterioration. Wood Research 77: 18-27.

VARGA, D.; VAN DER ZEE, M.E. 2008. Influence of steaming on selected wood properties of four hardwood species. Holz als Roh-und Werkstoff 66: 11–18.

VIITANIEMI, P.; JÄMSÄ, S.; VIITMAN, H. 1997. Method for improving biodegradation resistance and dimensional stability of cellulosic products. United States Patent. Nº5678324 (US005678324).

VITAL, B.; LUCIA, R.; DELLA, R.; EUCLIDES, R. 1983. Effect of heating on some properties of Eucalyptus saligna wood. Árvore 7 (2): 136–146.

ZAMAN, A.; ALEN, R.; KOTILAINEN, R. 2000. Thermal behavior of Pinus sylvestris and Betula pendula at 200–230C. Wood and Fiber Science 32 (2): 138–143.

ZANG, Y.M.; YU, Y.L.; YU, W.J. 2013. Effect of termal treatment on the physical and mechanical properties of phyllostachys pubescen bamboo. European Journal of Wood and Wood Products 71 (1): 61-67.
How to Cite
Knapic, S., Santos, J., Santos, J., & Pereira, H. (2018). Natural durability assessment of thermo-modified young wood of eucalyptus. Maderas. Ciencia Y Tecnología, 20(3), 489-498. Retrieved from