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This is the perfect timber for fine furniture, joinery or a feature floor.
Boasting a variety of colours ranging from light golden-brown to deep brown (sometimes with a reddish tint) and occasionally showing black streaks, the timber radiates a subtle beauty that makes it irresistible to Tasmanian designers. Additional character results from the grain of the wood, which can be straight or wavy with a natural lustre.
Blackwood is easily worked, very stable and long lasting, and blackwood artefacts are always statements of style and quality.
In addition to the supply of solid sections, the availability of high quality veneers has increased the timber's versatility for use in joinery, cabinet making, and feature panelling. Small cross sections of solid timber are also laminated, particularly for bench tops.
Blackwood is sourced from native forests. It is a common understorey species that readily grows from the coast to 1,000m above sea level but it excels in lowland swampy conditions. It will establish on the lower valley slopes of hilly and mountainous areas, up to the higher hill slopes and tablelands, and even on exposed mountaintops.
Blackwood is short-lived and fast growing. It has a vigorous spreading root system that suckers readily. After fire, it regenerates easily from seed and its young growth is particularly attractive to native animals. Blackwood is fairly resistant to frost, thrives in a moist atmosphere, and can tolerate shady and windy conditions. It grows well in many soil conditions: fertile, loam, poorly drained, well-drained, and even on the residue from tin-sluicing operations.
Blackwood grows best in the swamps and lowlands of the north-west of Tasmania in a variety of wet eucalypt forests.
36% of total Blackwood forest types are reserved.
Blackwood is one of the best known of Tasmania’s wattles. It can reach heights of 35m, but is generally around 10–20m, with a trunk up to 1m in diameter. Smaller trees branch from near ground level (shrub-like), and larger plants in forests have a well-developed trunk below the dense crown.
Blackwood flowers are densely packed, with stalks containing 30–50 ball-shaped flowers. They are whitish to pale yellow - typical of the wattle family - and flower in spring.
Blackwoods make good shade trees with prolific foliage.
Their leaves are olive green, lance-shaped and up to 16cm in length.
The tree’s bark is brown-grey to dark-grey and hard. It varies in thickness from less than 0.5 cm to 5 cm at the base in large trees and characteristically has long, vertical furrows along the trunk.
Because Blackwood thrives in wet conditions, the shady side of the tree often has a partial covering of grey lichens.
Blackwood Technical Details
- Dressed seasoned timber, 19 to 285mm wide by 19 to 45 mm thick is available in lengths up to 5400mm. Most production lengths are less than 3000 mm.
- Mainly straight, occasionally wavy (fiddleback figure).
- Even and medium.
- Durability Description
- Durable for internal use but should only be used externally if protected from the weather. Refer to AS 5604-2005 Timber - Natural durability ratings.
- In-ground: Class 3
- Above-ground: Class 3
- Movement - Shrinkage
- Approx. 1.5% radial, 4% tangential. Negligible collapse shrinkage.
- Unseasoned: 640 kg/cu m at 12% moisture content.
- Seasoned: 870 kg/cu m
- Strength Group
- Unseasoned: S4
- Seasoned: SD4
- Joint Group
- Unseasoned: J3
- Seasoned: JD3
- Structural Grades
- Most commonly available structural grade is number 3; F14 seasoned, F8 unseasoned.
- Toughness (Izod)
- Unseasoned: 15
- Seasoned: 13
- Hardness (Janka)
- Unseasoned: 4.6
- Seasoned: 5.9
Fire Hazard Properties
- Fire hazard Properties: Flooring (AS ISO 9239.1)
- Critial Radiant Heat Flux: Between 2.2 and 4.5 kW/m2
- Smoke Development Rate: Less than 750 %-min
- Fire Hazard Properties: Wall and Weiling Lining (AS/NZ 3837)
- Material Group: 3
- Average Extinction Area: Less than 250m2/kg
- Moderately high.
- Cuts fairly easily, cleanly and accurately. Moderate feeding forces required.
- Surfaces very smooth and lustrous. Care must be taken to work "with" the grain.
- Surfaces and edges are true, even end grain.
- Holes are usually clean and to size.
- Rebating + Mortising
- Cuts very cleanly, giving excellent results.
- Nails well although some seasoned material can tend to split. Nails hold reasonably well.
- Glues satisfactorily with most common adhesives.
- A very good bending timber. 25mm material bends well to a radius of 50mm
- Readily worked to a smooth, resilient finish and readily takes a high polish.
Blackwood Environmental Details
- Native - Wet Eucalypt and Rainforest
- 36% of the total Blackwood forest types are reserved
- Not available
- Chain of custody
- Carbon storage
- 396 kg/cu m
- R Values
- .61 (100mm)
- Blackwood's availability is limited, and is constrained by location and style of harvesting operations.