Silky Oak
August 14, 2011 | 11:06 pm UTC

Australia’s silky oak is lace-like, valuable and rare.

Family Name
Cardwellia sublimis and Grevillea robusta of the Family Proteaceae

Common Names
Silky oak, Australian silky oak, northern silky oak, selena, bull oak, oak, golden spangle wood

Average height is 80 to 100 feet, but trees can grow to 120 feet or taller. Average weight for Cardwellia sublimis is 34 pounds per cubic foot with a specific gravity of 0.53.

Average weight for Grevillea robusta is 36 pounds per cubic foot.

Wood can be difficult to dry.
Wood works easily with hand and machine tools with a slight blunting effect on cutting edges.

Experts recommend a reduced cutting angle when planing or moulding quartersawn material.
Good steam bending classification.

Australia’s silky oak has some oak-like qualities, but the Queensland native is not a true oak (Quercus). Australian silky oak is from the species Cardwellia sublimis and often goes by the commercial name lacewood, because of the lace-like figure found in some logs. Additional genera share the name silky oak, among them the species Grevillea robusta.

The Encyclopedia of Wood offers an explanation. “The name ‘silky oak’ is given to a number of different genera and species in Australia and New Zealand. The name originally referred to Grevillea robusta, a native of Southern Queensland, which also occurs in New South Wales. Cardwellia sublimis, from north Queensland, has similar characteristics and became known as silky oak and northern silky oak.” Grevillea robusta also has been introduced in East Africa, Africa, India, Sri Lanka, Brazil and the United States in Hawaii, California and Florida.

Silky oak, also known as silk oak, silver oak and lacewood, from Grevillea robusta, is a medium-height to tall tree, growing to 120 feet or more. In addition to timber uses, the wood is very popular as an ornamental tree, because of its distinctive yellow flowers.

A Wood of Many Uses

Shayne Lachlan, vice president of Moxon Timbers Inc., Winchester, VA, knows a lot about Australian silky oak. His former home in Australia was built with it, inside and out, including studs, walls and paneling. “It was over 200 years old. The wood had been painted and we stripped the paint and restored it to the original [look].” Lachlan’s company, based in Australia and New Zealand imports a small amount of silky oak, mainly because the availability is so “tight,” said Lachlan. “We bring in a little bit, but not as much as we used to. It’s getting a bit scarce, mainly because it has been popular since the 1800s and used for just about everything, from wall studs and paneling to cladding and flooring.”

Lachlan said silky oak is popular with architects and custom furnituremakers. “It is a very unique wood. We sell it to people doing fretwork and inlays, and it’s used in a lot of cabinetwork. The hobbyists love it because it is an unusual wood. If they are building a toy or cabinet or jewelry box, silky oak stands out.”

In Australia, silky oak is a popular choice for furniture and decorative paneling, said Lachlan. While flooring was once a major market, other harder, less expensive Australian woods have taken its place.

Mark Mills, owner of Lacewood Furniture in Queensland, has been using North Queensland silky oak in antique and period style furniture, since his company was founded in 1993. Mills describes silky oak (Cardwellia sublimis) as one of the primary cabinet timbers used in Queensland in the early 1900s. His heirloom furniture designs include handmade carvings, traditional mouldings and hardware in Art Nouveau and other styles and periods.

In Australia, silky oak has been used in applications as a substitute for oak, but Miles Gilmer, owner of Gilmer Wood Co., Portland, OR, said he thinks the look is only because of the large medullary rays. “It might resemble the look of quartersawn oak somewhat, but oak has less luster and chatoyance.”

Traditional uses for silky oak include decorative veneer, architectural woodwork, parquet and plank flooring, cabinetry, furniture and interior joinery. In Australia, it is also used for building construction work and shutters, as well as cask staves.

A Lacy Substitute

Gilmer said it is rare to see the Grevillea or Cardwellia species in the United States. “Those species, also known as lacewood, are noted for their large medullary rays and a silvery grain on the radial surface, which is generally why people like them.” Gilmer said though, that getting the species in the United States has been difficult.

“What some people are using as a replacement is Brazilian lacewood. It looks very similar to the Australian silky oak or lacewood. Brazilian lacewood comes from the species Roupala brasiliensis,” said Gilmer. “Lacewood is one of those names that has almost become generic.”

Lachlan agreed that users have turned to the Brazilian species, “which is very similar to silky oak, although the Brazilian wood is slightly darker. If a customer wants lacewood in volume, they would use the Brazilian wood.”

Reference material describes Brazilian lacewood as a reddish brown species with an unusual grain pattern, consisting of a multitude of eyes. In the book Know Your Woods by Albert Constantine Jr., the author writes that lacewood logs “vary in color from…shell pink to a light reddish brown and they have a striking figure, varying from a small lace-like pattern to a large splash-like figure.” The heartwood of both species, according to The Encyclopedia of Wood, is pink to reddish brown, but deepens in color as it matures.

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