Overview
The common name “Ironbark” comes from the trees tendency to not shed its bark annually like many other eucalyptus, resulting in an accumulation of dead bark. This layer of bark protects the living tissue inside the tree from fires, and with a silvery-grey colour looks quite similar to iron metal and hence the name. Ironbark is usually seen growing, in both native forests and plantations, in the western area of NSW up to southern QLD, with some trees growing in northern VIC. Ironbark has a very high natural resistance to rot due to chemistry of the tree which helps fight off fungus. The heartwood has a deep red colour which is a great contrast to the pale yellow sapwood. Both heartwood and sapwood are often seen together in decking boards. Ironbark timber has an interlocked grain with a fine texture. Ironbarks popularity is ever increasing with more and more homes using the timber for decks, landscaping and cladding due to its high durability and fire resistance.
Pros & Cons
| PROS | CONS |
|---|---|
| High rot and termite resistance | Hard to work |
| Very high durability, hardness and density | Boards need to be pre-drilled |
| Widely available | Expensive |
| Used for over 200 years in heavy construction | Short oil life of decking due to density |
| Little tannin leach | Mostly supplied in random lengths |
| 1 of 7 hardwoods recommended by the building commission for bushfire prone areas | Red ironbark is Lyctid borer susceptible |
Properties
| Name | Eucalyptus Sideroxylon (red) Eucalyptus Paniculata (grey) |
|---|---|
| Colour (Heartwood) | Light grey / chocolate to deep red |
| Colour (Sapwood) | Pale yellow |
| Durability | Class 1 |
| Density | 1090 kg/m3 |
| Hardness | Janka rating 14 |
| Checking rating | |
| Shrinkage rating | |
| Availability | Readily Available |
| BAL Rating | Grey 12.5 19 Red 12.5 19 29 |
| Termite Resistant | YES |
| Lyctid Borer Susceptible | NO (grey) YES (red) |
| Tannin Leach | Little |
| Origin | VIC, NSW, QLD |
