Grevillea robusta
Encyclopedia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, in riverine, subtropical and dry rainforest environments receiving more than 1,000 mm per year of average rainfall. It is a fast growing evergreen
Evergreen
In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...
tree, between 18–35 m tall with dark green delicately dented bipinnatifid leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
reminiscent of a fern
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...
frond. It is the largest plant in the Grevillea genus, reaching diameters in excess of one metre. These leaves are generally 15–30 cm long with greyish white or rusty undersides. Its flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are golden-orange bottlebrush
Bottlebrush
Callistemon is a genus of 34 species of shrubs in the family Myrtaceae, all of which are endemic to Australia. It is sometimes considered a synonym of Melaleuca, and four Callistemon species from New Caledonia were moved to that genus by Lyndley Craven and John Dawson in 1998...
-like blooms, between 8–15 cm long, in the spring, on a 2–3 cm long stem and are used for honey production. The seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s 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.
Uses
Before the advent of aluminium, the timber from this tree was widely used for external window joinery as it is resistant to rotting. It was also popular for making furniture. There are severe restrictions on the harvesting of this tree now as the number of trees became depleted. Silky Oak is a valuable timber and was one of Australia’s best known cabinet timbers.It is the best tree which can be used for fencing and it is one of the fastest growing trees.
Cultivation
When young it can be grown as a houseplantHouseplant
A houseplant is a plant that is grown indoors in places such as residences and offices. Houseplants are commonly grown for decorative purposes, positive psychological effects, or health reasons such as indoor air purification...
where it can tolerate light shade, but prefers full sun as it grows best in warm zones. If planted outside, young trees need protection on frosty nights. Once established it is hardier and tolerates temperatures down to about −8 °C (17 °F). It needs occasional water but is otherwise fairly drought-resistant.
Grevillea robusta is often used as stock for grafting difficult-to-grow grevilleas.
Care needs to be taken when planted near bushland as it can be weedy.
The tree has been planted widely throughout the city of Kunming in south-western China forming shady avenues.
Grevillea robusta (Southern Silky Oak) is also grown in plantations in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
and can also be grown along side maize
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...
in agroforestry
Agroforestry
Agroforestry is an integrated approach of using the interactive benefits from combining trees and shrubs with crops and/or livestock.It combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy and sustainable land-use systems.-Definitions:According to...
systems.
Toxicity and allergic reactions
The flowers and fruit contain toxic hydrogen cyanide. Tridecylresorcinol in G.robusta is responsible for contact dermatitisContact dermatitis
Contact dermatitis is a term for a skin reaction resulting from exposure to allergens or irritants . Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight....
.