Ironbark – Grey

Red Timber Species

Species Name: Ironbark – Grey

Botanical name(s): Eucalyptus paniculata
Eucalyptus siderophloia

Size and location information: The most common commercial species of Grey Ironbark is Eucalyptus paniculata, which is distributed from the far south coast of NSW to north of Coffs Harbour. Another species also referred to as Grey Ironbark is E. siderophloia. It is distributed from southern coastal NSW to Maryborough in Queensland.

Description: The heartwood of the Grey Ironbarks ranges from light grey or light chocolate with some darker reds and browns sometimes occurring. Sapwood is slightly lighter in colour. Grey Ironbark may have various regional variations such as the ‘Black Ironbarks’ around Port Macquarie, which have similar light colours with black narrow to broad streaks running through the timber. Texture is moderately coarse and even.

Ironbarks are a very characteristic group of trees, so named on account of the thick, compact, hard bark. The name however could equally apply to the timber itself, for it is certainly the ironwood of the whole Eucalyptus genus.

Density: Green: 1250kg/m3 Dry: 1100kg/m3

Janka Hardness Rating: Green: 11.0, Dry: 16.3

Shrinkage: 4.5% Radial, 7.5% tangential

Durability: In ground: Class 1 Above ground: Class 1

Lyctids Susceptibility: No

Termite Resistance (AS3660): Yes

Strength Group: S1/SD1

Fire Hazard properties:
Spread of flame: 3
Smoke Development: 3

The wood is very heavy, hard and compact, making working with the timber difficult. It ishard to nail and planes with difficulty. Microscopically, the fibres are seen to be very thick walled, compact and closely compressed.

The timber is very hard to work, limiting some applications requiring fine detailing.

Applications include heavy engineering, marine structures, poles, boat building, framework, flooring and decking. It was one of the first species to be utilised by the early settlers in the neighbourhood of Port Jackson, for bridging, house building, piles and generally where great strength and durability were required.

Plentiful. Select joinery grade grade tends to have a lot shorter length spec.

Click here to get back to Timber Species List.