Timber Profile - Spotted Gum
Corymbia maculata, Lemon-scented Gum, Spotted Irongum, Eucalyptus maculata, Corymbia citriodora, Eucalyptus citriodora, Corymbia henryi, Eucalyptus henryi Spotted Gum is the common name for a collective of four species that grow along the east coast of Australia, from northeast Victoria to the northern tablelands of Queensland, with some pockets in western areas of southern Queensland.
With straight, slender trunks and smooth bark that is shed in patches, the name comes from the characteristic spotted appearance. These species can grow to 45 m in height and 1.3 m in stem diameter, but often only half this size on less favourable sites. Colour tones range from pink to grey-blue.
Corymbia citriodora subsp. variegata occurs mainly in the coastal areas of northern New South Wales and southern Queensland, but also in western areas of southern Queensland. C. citriodora subsp. citriodora grows from the mid-north coast of NSW to the Windsor Tableland, North Queensland.
C. maculata occurs from Bega (NSW) to the mid-north NSW coast, and also a disjunct occurrence in eastern Victoria. C. henryi grows in northern New South Wales and southern Queensland. Locally, you will see ample Spotted Gums growing in the Bega Valley, with the forests north of Tathra and towards Tanja on the coast road a particularly good example - their distinctive and appealing bark patterns makes them easy to identify. The heartwood colouring ranges from light brown through to dark red-brown. The sapwood is usually white and up to 50 mm wide. Growth rings are absent, with vessels being small to moderately large, generally arranged in short radial multiples. Vessel lines are very prominent on dressed longitudinal surfaces. Tyloses & paratracheal (surrounding pores) are abundant making the wavy grain and attractive fiddleback figures which are sought after by furniture makers. The texture is open, often with interlocked grain and it is slightly greasy to the touch.
Durability above-ground is Class 1 - with life expectancy over 40 years, and durability in-ground is Class 2 - life expectancy 15 to 25 years. Although untreated wood can be susceptible to lyctid borer attack, Spotted Gum is termite resistant.
A very hard timber (rated 1 on a 6 class scale) in relation to resistance to indentation and ease of working with hand tools. Spotted Gum also machines well due to its natural greasiness.
Will readily accept paint, stain and polish and due to the lower tannin content than most other eucalypts, so staining of paintwork, brickwork etc, is less likely to occur as a result of water running over unpainted timber surfaces. Commonly used for engineering as sawn or round timber in wharf and bridge construction, railway sleepers, cross-arms, poles, piles and mining timbers.
For construction, Spotted Gum is used as unseasoned timber in general house framing and as seasoned dressed timber in cladding, internal and external flooring, linings and joinery.
Also used in fencing, landscaping, retaining walls and as structural plywood and hardboard.
An excellent choice for exterior cladding, being a fire resistant species.
The delightful grain characteristics are in demand for fine furniture, turnery, joinery and parquetry. Outdoor furniture made from Spotted Gum has consistently won industry awards in Australia and it is exported to a range of destinations around the world. Other uses include tool handles, boat building (keel and framing components, planking, decking), coach, vehicle and carriage building, agricultural machinery and sporting goods such as baseball bats, croquet mallets, spring and diving boards and parallel bars. Suitable for bent work, steaming, carving and woodturning, Spotted Gum is used frequently by creative craftsmen. Also commonly used for mallet heads, ladder rungs, wheel spokes, wine casks and broom handles, Spotted Gum is the main Australian species for tool handles & any applications which are subjected to high impact forces - such as axe handles. In the food industries, Spotted Gum is used for butcher’s skewers & butcher's blocks and dry sawdust is a favoured smoking and curing medium.
Another one of Australia’s premium native hardwoods with a high degree of natural durability and strength combined with a striking appearance and versatility.
An ideal timber for a variety of structural, exterior and interior applications. Spotted Gum is valued throughout the world by architects and designers for it's grain structure, attractive markings and unique colour palette.