Slash pine

• Medium-sized tree.
• Grows 30–35m high and stem to 0.7m diameter.
• Branches are usually large and spreading.
• Bark is grey to red-brown, thick, rough, and deeply fissured.
• Bark sheds in small scales.

• Grown in plantations in the coastal regions of northern New South Wales to Rockhampton, Queensland.
• Introduced into Queensland in the late 1920s.
• Native to south-east United States from South Carolina to Florida and west to Louisiana.

Colour

• Heartwood is reddish brown to shades of yellow.
• Sapwood is usually pale yellow to yellow.

Grain

• Generally straight.
• Obvious difference in colour between earlywood and latewood results in a very distinctive figure (pattern) when back-sawn.

Engineering

• Preservative-impregnated poles for pole-frame construction, power poles, piles.

Construction

• General purpose softwood used as dressed seasoned timber in general house framing, flooring, lining, joinery, mouldings, and laminated beams.
• Preservative impregnated for external cladding, decking, fascia and barge boards; and seasoned sawn or round forms in fencing, pergolas, landscaping, retaining walls and playground equipment.
• Structural plywood and reconstituted panel products such as particleboard and medium-density fibreboard.

Decorative

• Furniture, plywood, joinery, turning.

Others

• Scaffold planks, wood wool, paper products.

• Density: 625kg/m³ at 12% moisture content; about 1.6m³ of seasoned sawn timber per tonne.
• Strength groups: Pinus elliottii var. elliottii—S5 unseasoned, SD5 seasoned. P. elliottii var. densa—(S5) unseasoned, (SD5) seasoned (brackets indicate provisional value).
• Stress grades: F4, F5, F7, F8, F11 (unseasoned); F7, F8, F11, F14, F17 (seasoned) when visually stress-graded according to AS 2858—2008: Timber—Softwood—Visually stress-graded for structural purposes.
• Joint groups: J4 unseasoned, JD3 seasoned.
• Shrinkage to 12% MC: 4.8% (tangential), 3.0% (radial).
• Unit shrinkage: 0.29% (tangential), 0.20% (radial)—these values apply to timber reconditioned after seasoning.
• Durability above-ground: Class 4 (life expectancy less than 7 years).
• Durability in-ground: Class 4 (life expectancy less than 5 years).
• Lyctine susceptibility: sapwood is not susceptible to lyctid borer attack.
• Termite resistance: resistant.
• Preservation: immature plantation-grown stems are almost entirely sapwood, which typically comprises more than 50% of the stem radius even in mature plantations; sapwood readily impregnates with commercial preservative but the heartwood can’t be adequately treated using available commercial processes.
• Seasoning: to avoid distortion, dry framing sizes at high temperatures; boards may be air-dried or kiln-dried at conventional or high temperatures.
• Hardness: firm (rated 4 on a 6-class scale) to indent and work with hand tools.
• Machining: keep planer blades sharp when dressing to avoid compressing the softer earlywood and causing ridged surfaces.
• Fixing: nails tend to follow the growth rings due to deflection by latewood bands; be careful when using standard fastening and fittings; use a nailing gun for good results.
• Gluing: glue can absorb differently between earlywood and latewood, but this rarely causes problems.
• Finishing: be careful when you select timber for finishing and when you prepare surfaces for paint and varnish due to the high resin content of some material and earlywood/latewood ridging of dressed timber.

General characteristics

• Sapwood: pale yellow to yellow.
• Heartwood: reddish brown to shades of yellow.
• Texture: non-uniform, alternating bands of earlywood and latewood; transition from earlywood to latewood is moderately abrupt; grain is straight; knots usually present in constructional timber grades.

Wood structure

• Growth rings: clearly visible due to the latewood forming a dense, dark band; false annual rings are occasionally present.
• Vessels: absent.
• Resin canals: numerous, prominent as lines on dressed longitudinal surfaces.
• Rays: fine, visible with a lens.
• Parenchyma: absent

Other features

• Odour: wood, generally, has a strong resinous odour.

• 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, 2000, AS 2858—2008: Timber—Softwood—Visually stress-graded for structural purposes, Standards Australia International, Strathfield, NSW.