Grevillea robusta (Silky oak)
Species: G. robusta
Binomial name: Grevillea robusta
Common name: Southern silky oak, Silky oak, Australian silver oak.
The flowers and fruit contain toxic hydrogen cyanide.
Tridecylresorcinol in G.robusta is responsible for contact dermatitis.
Grevillea robusta is the largest species in the genus Grevillea of the family Proteaceae. It is not closely related to the true oaks, Quercus. It is a native of eastern coastal Australia, in riverine, subtropical and dry rainforest environments receiving more than 1,000 mm per year of average rainfall.
It is a fast-growing evergreen tree, between 18–35 m tall, with dark green delicately dented bipinnatifid leaves reminiscent of a fern frond. It is the largest plant in the Grevillea genus, reaching diameters in excess of 1 m. The leaves are generally 15–30 cm long with greyish white or rusty undersides.
In spring 8–15 cm long golden-orange bottlebrush-like appear on 2–3 cm long stems.. Like others of its genus, the flowers have no petals, instead they have a long calyx that splits into 4 lobes. The seeds mature in late winter to early spring, fruiting on dark brown leathery dehiscent follicles, about 2 cm long, with one or two flat, winged seeds.
Before the advent of aluminum, Grevillea robusta timber was widely used for external window joinery, as it is resistant to wood rot. It has been used in the manufacture of furniture, cabinetry, and fences. Owing to declining G. robusta populations, felling has been restricted.
Recently G. robusta has been used for side and back woods on guitars made by Larrivée and others, because of its tonal and aesthetical qualities.
Photographed at Pukekura Park, New Plymouth
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