''Grevillea'', commonly known as spider flowers, is a genus of about 360 species of evergreen flowering plants in the family Proteaceae. Plants in the genus ''Grevillea'' are shrubs, rarely trees, with the leaves arranged alternately along the branches, the flowers zygomorphic, arranged in racemes at the ends of branchlets, and the fruit a Follicle (fruit), follicle that splits down one side only, releasing one or two seeds.

Description

Plants in the genus ''Grevillea'' are shrubs, rarely small trees with Leaf#Divisions of the blade, simple or Leaf#Divisions of the blade , compound leaves arranged alternately along the branchlets. The flowers are zygomorphic and typically arranged in pairs along a sometimes branched raceme at the ends of branchlets. The flowers are Plant reproductive morphology#Bisexual, bisexual, usually with four tepals in a single Whorl (botany), whorl. There are four stamens and the gynoecium has a single carpel. The fruit is a thin-walled follicle that splits down only one side, releasing one or two seeds before the next growing season.

Taxonomy

The genus ''Grevillea'' was first formally described in 1809 by Joseph Knight (horticulturist), Joseph Knight from an unpublished manuscript by Robert Brown (botanist, born 1773), Robert Brown. Knight gave the spelling ''Grevillia'', corrected by Brown in 1810 to ''Grevillea'' in ''Transactions of the Linnean Society of London''. The genus was named in honour of Charles Francis Greville, an 18th-century patron of botany and co-founder of the Royal Horticultural Society.

Species

There are over 350 species which are endemic (ecology), endemic to Australia. Five other species are endemic to areas outside Australia. Three of these (''Grevillea exul, G. exul'', ''Grevillea gillivrayi, G. gillivrayi'', and ''Grevillea meisneri, G. meisneri'') are endemic to New Caledonia, while ''Grevillea elbertii, G. elbertii'' and ''Grevillea papuana, G. papuana'' are endemic to Sulawesi and New Guinea respectively. Two other species, ''Grevillea baileyana, G. baileyana'' and ''Grevillea glauca, G. glauca'', occur in both New Guinea and Queensland.

Distribution and habitat

Grevilleas grow in most habitats, although few grow in alpine areas, in swamps or saline soils. Most species are endemic to Australia but three species grow in New Guinea, (''Grevillea papuana, G. papuana'' is endemic), three are endemic to New Caledonia and one species (''Grevillea elbertii, G. elbertii'') is endemic to Sulawesi in Indonesia.

Ecology

Grevilleas are good Plants which attract birds, bird-attracting plants. Honeyeaters in particular are common visitors. They are also used as food plants by the larvae of some Lepidoptera species, including the dryandra moth and ''Pieris rapae'' (small butterfly or cabbage white butterfly).

Uses

Use in horticulture

Many species of grevilleas are popular garden plants, especially in Australia but also in other temperate and subtropical climates. Many grevilleas have a propensity to interbreed freely, and extensive hybridisation and selection of horticulturally desirable attributes has led to the commercial release of many named cultivars. Among the best known is 'Robyn Gordon', a small shrub up to high and wide which can flower 12 months of the year in subtropical climates. The cultivar 'Canberra Gem' has gained the Royal Horticultural Society's Award of Garden Merit. They can be grown from soft tip cuttings from December–March (in the Southern Hemisphere) or fresh seed. Many harder-to-grow species can be grafted onto hardy rootstock such as ''Grevillea robusta''. There is an active Grevillea Study Group in the Australian Native Plants Society (Australia), Australian Native Plants Society for people interested in grevilleas, both for uses in horticulture and for conservation in the wild.

Traditional Aboriginal use

Grevillea flowers were a traditional favourite among the Aboriginal Peoples for their sweet nectar. This could be shaken onto the hand to enjoy, or into a coolamon (vessel), coolamon with a little water to make a sweet drink. They might be referred to as the original "bush lollies". Drinking nectar direct from the flower is best avoided as some commonly cultivated grevillea species produce flowers containing toxic cyanide.Everist, S.L., ''Poisonous Plants of Australia'', Angus & Robertson, 1974.

Colonial furniture

A grevillea wood veneer was used on a Pembroke table, a small table with two drawers and folding sides, made in the 1790s for Commissioner of the Royal Navy, Sir Andrew Snape Hamond. The timber from which the veneer was made, referred to as 'beef wood', was sent from Port Jackson by Surgeon-General John White (surgeon), John White, who arrived in the new penal colony of Australia with the First Fleet. This table is in the collection of the National Museum of Australia in Canberra.

Gallery

Image:Grevillea candelabroides mingenew email.jpg, ''Grevillea candelabroides, G. candelabroides'' Image:Grevillea dielsiana.jpg, ''Grevillea dielsiana, G. dielsiana'' Image:Grevillea wickhamii aprica grafted email.jpg, Grevillea wickhamii, ''G. wickhamii'' subsp. ''aprica'' Image:Grevillea rivularis.jpg, ''Grevillea rivularis, G. rivularis''

References

External links

ANPSA.org: Grevillea website
— ''by Australian Native Plants Society, ASGAP−Australian Native Plants Society''.
Grevilleapark.org: Illawarra Grevillea Park website
* PlantList]
search for Grevillea
Retrieved 20190318. {{Taxonbar, from=Q1545761 Grevillea, Proteaceae genera Taxa named by Robert Brown (botanist, born 1773) Proteales of Australia Australasian realm flora