Timber Profile - Ironbark
Family: Myrtaceae
Grey Ironbark - Eucalyptus paniculata, soemtimes known as White Ironbark, Eucalyptus drepanophylla, Eucalyptus siderophloia, Eucalyptus decepta
Red Ironbark - Eucalyptus sideroxylon Eucalyptus creba, Eucalyptus fibrosa
Ironbark is a premium native hardwood that is well regarded as a high quality timber in Australia - and has been sought after throughout history. It has a wide range of applications from sporting goods to construction to flooring and decorative furniture. A medium sized tree of 30 to 50m with a stem diameter of 1.5m, the bark is hard and coarse with deep furrows and ridges, ranging from dark brown to black in colour.
Grey Ironbark species E. drepanophylla is found from northern New South Wales to Bundaberg, Queensland as well as in patches as far north as the Atherton Tablelands. E. paniculata is found in New South Wales only from Bega to Coffs Harbour.
The two most common Red Ironbarks are Mugga Ironbark (Eucalyptus sideroxylon) and Narrow-leaved Red Ironbark (E. creba). A third Ironbark that also falls into this category is Broad-leaved Red Ironbark (E. fibrosa). Mugga Ironbark extends from Victoria through the western slopes of NSW into southern Queensland. Narrow-leaved Red Ironbark is found in the coastal, tablelands and western plains areas of central to northern NSW and extends well up into Queensland in a belt between the coast and the just west of the Great Dividing Range. Broad-leaved Red Ironbark has a wide distribution from the south coast of NSW to central coastal Queensland.
Ironbark is well known as a very heavy timber - 1120 kilograms per cubic metre - it is dense and can be hard to work with. Dressed surfaces take on a steely sheen similar to iron. It is hardness rated 1 on a scale of 1 - 6. It is more difficult to machine due to these unique hardness properties.
Grey Ironbark sapwood is almost white, quite distinct from the heartwood, which varies from reddish-brown to dark brown. In Red Ironbark, the heartwood colour is a deep red. The sapwood is a distinctive pale yellow in colour. Texture is medium and uniform, with the grain usually straight, sometimes interlocked. Growth rings are absent with vessels small to medium, often containing tyloses. Durability above-ground is Class 1 - life expectancy over 40 years. Durability in-ground is Class 1 - life expectancy over 25 years. The sapwood is not susceptible to lyctid borer attack and Ironbark is termite resistant.
A fire resistant species suitable for most bushfire prone areas. Uses include general house framing and as seasoned dressed timber in cladding, internal and external flooring, linings and joinery. Also suitable for fencing, landscaping and retaining walls. Decorative uses include outdoor furniture, turnery, joinery.
Ironbark cladding is an ideal choice for it's superb good looks, fire rating and durability.
Highly suitable for boat building, regarded as the timber of choice for wooden-hulled vessels used in Antarctic exploration because of its high strength and toughness giving the hulls high resistance to pack ice damage and crushing. Also used for wheel spokes and bowling pins thanks to the resilient properties.
Particularly spectacular for big posts, it's a popular choice with designers and architects and for use in pole houses, wharfs & bridges - anywhere you need a outstanding resilient & hard timber.
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