Australian Tropical Rainforest Plants - Online edition

Grevillea robusta A.Cunn. ex R.Br.


Weed
Tree
Click/tap on images to enlarge
Leaves and Flowers. © CSIRO
Scale bar 10mm. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Brown, R. (1830) Prodromus Florae Novae Hollandiae - Suppl. 1 : 24. Type: Ora orient., Moreton Bay, 1827, A. Cunningham.

Common name

Southern Silky Oak; Warragarra; Silk Oak; Oak, Silky; Oak, Silk; Oak, Southern Silky; Silky Oak

Stem

Oak grain in the wood and a corresponding pattern in the inner blaze.

Leaves

Oak grain in the twigs. Terminal buds and the underside of mature leaves densely clothed in prostrate white hairs. Compound leaf petioles clothed in prostrate, white hairs. Leaves about 10-27 cm long, leaflet blades entire or lobed about 3-9 cm long.

Flowers

Raceme secund. Perianth tube somewhat dilated towards the base. Hypogynous gland one, horseshoe-shaped. Ovules 2 per ovary. Stigma conical, +/- terminal.

Fruit

Fruits about 15-19 x 12 mm. Seeds with a marginal wing, seed + wing about 11-13 x 8-10 mm.

Seedlings

Cotyledons obovate about 14-16 x 8-11 mm, +/- 3-veined. First pair of leaves simple, margins usually lobed, occasionally entire. At the tenth leaf stage: leaf blade pinnatifid, each lobe +/- pungent; leaves sparsely clothed in pale, woolly hairs. Seed germination time 13 to 15 days.

Distribution and Ecology

Endemic to Australia, occurs naturally in south-eastern Queensland and north-eastern New South Wales but is now widely cultivated and has become naturalised in NEQ on the Atherton Tableland. Altitudinal range in NEQ from 700-800 m. Grows on farmland and in rain forest regrowth.

Natural History & Notes

This species is now cultivated around the world for the stunning display of orange flowers which attract birds and for its ease of culture and adaptability.

Synonyms
Grevillea robusta R.Br. var. robusta, The Gardener's Chronicle ser. 3, 49 : 376(1911). Stylurus robusta (A.Cunn. ex R.Br.) O.Deg., Flora Hawaiiensis Fam. 98 : (1932). Grevillea umbratica Meisn., Prodromus 14(1): 381(1856), Type: In sylvis umbrosis siccis ad fl. Brisbane et Moreton Bay (A. Cunn!). Grevillea robusta var. compacta Anon., The Gardener's Chronicle ser. 3, 49 : 376(1911), Type: Shown by Mr. R.B. Leach, Dulwich.
RFK Code
989
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