Northern cypress

• Small to medium conifer.
• Slow growing, 20–30m high.
• Foliage is blue-green to dark green.

• Occurs across northern Australia in habitats with free draining (sandy) soils.

Colour

• Heartwood is pale yellow to streaky gold and brown.
• Sapwood is whitish pale yellow.
• As with other cypress timbers, knots are a feature.

Grain

• Generally fine and even, occasionally interlocked, producing an attractive figure (pattern).

• Construction: used as sawn timber in general house framing, internal and external flooring, linings, joinery and fencing.
• Decorative: internal furniture, outdoor furniture, turnery.
• Others: beehives, oyster stakes, essential oil (Australian blue cypress, blue cypress oil).

• Density: 675kgm³ at 12% moisture content; about 1.5m³ of seasoned sawn timber per tonne.
• Strength groups: S4 unseasoned, SD5 seasoned.
• Stress grades: F4, F5, F7 (seasoned and unseasoned) when visually stress-graded according to AS 2858—2008: Timber—Softwood—Visually graded for structural purposes.
• Joint groups: J3 unseasoned, JD3 seasoned.
• Shrinkage to 12% MC: 2.8% (tangential), 2.1% (radial).
• Unit shrinkage: 0.22% (tangential), 0.18% (radial); low shrinkage, very stable timber.
• Durability above-ground: Class 1 (provisionally)—life expectancy over 40 years.
• Durability in-ground: Class 1—life expectancy 15–25 years; heartwood highly resistant to decay when fully exposed to the weather and/or used in the ground.
• Lyctine susceptibility: not susceptible.
• Termite resistance: resistant to subterranean termites.
• Preservation: negligible penetration of heartwood and sapwood using current commercial processes.
• Seasoning: satisfactorily dries using conventional air and kiln seasoning.
• Hardness: firm to indent and work with hand tools.
• Machining: machines well.
• Fixing: pre-drill before hand-nailing seasoned timber to prevent splitting.
• Gluing: rough the surface to enhance the strength of the bond.
• Finishing: readily accepts paint, stain and polish.

• Boland, DJ, Brooker, MIH, Chippendale, GM, Hall, N, Hyland, BPM, Johnston, RD, Kleinig, DA and Turner, JD 2006, Forest trees of Australia, 5th ed., CSIRO Publishing, Collingwood Australia.
• Bootle, K 2005, Wood in Australia: Types, properties and uses, 2nd ed., McGraw-Hill, Sydney.
• Ilic, J 1991, CSIRO atlas of hardwoods, Crawford House Press, Bathurst, Australia.
• Queensland Government, DAF 2018, Construction timbers in Queensland: Properties and specifications for satisfactory performance of construction timbers in Queensland. Class 1 and Class 10 buildings, Books 1 & 2, Department of Agriculture and Fisheries, Brisbane.
• Standards Australia, 2008, AS 2082—2008: Timber—Softwood— Visually stress-graded for structural purposes, Standards Australia International, Strathfield, NSW.