Grevillea shiressii

Grevillea shiressii
Near Pearl Beach
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Proteales
Family: Proteaceae
Genus: Grevillea
Species:
G. shiressii
Binomial name
Grevillea shiressii

Grevillea shiressii, also known as Mullet Creek Grevillea[3][4] is a threatened species of flowering plant in the family Proteaceae and is endemic to New South Wales where it is found in only two localities near Gosford. It is a tall, erect shrub with oblong to narrowly lance-shaped leaves with distinctive intramarginal veins and small clusters of green to bluish-grey, later cream-coloured flowers with a brownish-maroon style.

Description

Grevillea shiressii is an erect, woody shrub that typically grows to a height of 1.5–5 m tall (4 ft 11 in – 16 ft 5 in). Its leaves are oblong to narrowly lance-shaped, mostly 8–19 mm (0.31–0.75 in) long and 13–30 mm (0.51–1.18 in) wide, sometimes with wavy margins. Leaves have a distinctive pattern with conspicuous marginal veins 2–4 mm from the margins.

The flowers are arranged on the ends of branches or in leaf axils, in loose clusters of 2 to 10 on a rachis 1–8 mm (0.039–0.315 in) long, each flower on a pedicel 9–19 mm (0.35–0.75 in) long, the pistil 27–32 mm (1.1–1.3 in) long. The flowers are green in the bud stage, later bluish-grey to mauve, finally cream-coloured, the style brownish maroon. Flowering mainly occurs from July to December, and the fruit is a glabrous, elliptic follicle 14–16 mm (0.55–0.63 in) long.[5][6][7][8]

This grevillea is similar to, but easily distinguishable from the related G. singuliflora, a species from Queensland which grows only 0.5–1.5 m (1 ft 8 in – 4 ft 11 in) tall, has solitary or paired flowers and small, ovate leaves 0.7–3.5 cm (0.28–1.38 in) long and 10–23 mm (0.39–0.91 in) wide.[4][9]

Taxonomy

Grevillea shiressii was first formally described in 1925 by William Blakely in the Proceedings of the Linnean Society of New South Wales.[10][11] The specific epithet (shiressii) honours David William Campbell Shiress,[4] Blakely's "friend and companion on many botanical excursions".[11]

Distribution and habitat

This grevillea grows on alluvial sandy soils in forests along creek banks, under such trees as mountain blue gum (Eucalyptus deanei), turpentine (Syncarpia glomulifera) and rough-barked apple (Angophora floribunda), and alongside watergum (Tristaniopsis laurina) and river lomatia (Lomatia myricoides). It is only found growing naturally along two tributaries of the lower Hawkesbury River near Gosford north of Sydney, Mullet Creek near Wondabyne and Mooney Mooney Creek.[6][8][12]

Ecology

Birds forage among and pollinate the flowers of G. shiressii, while ants disperse the seeds. Wasps of the genus Eurytoma prey on the seeds. Plants are killed by fire and regenerate from seed.[8]

Conservation status

Grevillea shiressii is listed as endangered on the IUCN Red List of Threatened Species and as vulnerable under the Australian Government Environment Protection and Biodiversity Conservation Act 1999 and the New South Wales Government Biodiversity Conservation Act 2016 (NSW). The main threats to the species include its restricted distribution, track maintenance, inappropriate fire regimes, and weed invasion.[12][13][1]

Use in horticulture

Grevillea shiressii is grown as an ornamental plant, both for its foliage and unusual flowers among grevilleas. It is a bird-attracting plant which tolerates a wide variety of climatic conditions. It can tolerate frost but not drought and must be frequently watered. Cultivated plants usually grow into rounded, spreading shrubs up to 3m by 3 m (9.8 ft).[4]

It is usually propagated from seed, but can be also be grown from cuttings. Seedlings can often be found germinating underneath parent plants.[4]

Hybrids

A cultivar known as G. 'Ruby Clusters' or G. 'Splendour' is a hybrid between G. shiressii and either G. oleoides or G. victoriae, with the red flowers of these species and the foliage of the former.[4]

References

  1. ^ a b Makinson, R.; Auld, T.D. (2020). "Grevillea shiressii". IUCN Red List of Threatened Species. 2020: e.T113082264A113309710. doi:10.2305/IUCN.UK.2020-2.RLTS.T113082264A113309710.en. Retrieved 28 July 2025.
  2. ^ "Grevillea shiressii". Australian Plant Census. Retrieved 1 February 2023.
  3. ^ "Species: Grevillea shiressii (Mullet Creek Grevillea)". Atlas of Living Australia. Retrieved 28 July 2025.
  4. ^ a b c d e f Olde, Peter; Marriott, Neil (1995). The Grevillea Book Volume 3. Australia: Kangaroo Press. pp. 170–71, 175. ISBN 0864176112.
  5. ^ Makinson, Robert O. "New South Wales Flora Online: Grevillea shiressii". Royal Botanic Gardens & Domain Trust, Sydney, Australia. Retrieved 7 January 2013.
  6. ^ a b "Grevillea shiressii". Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 2 February 2023.
  7. ^ Wrigley, John W.; Fagg, Murray A. (1991). Banksias, waratahs & grevilleas : and all other plants in the Australian Proteaceae family. North Ryde, NSW, Australia: Angus & Robertson. pp. 329–330. ISBN 0207172773.
  8. ^ a b c Benson, Doug; McDougall, Lyn (1999). "Ecology of Sydney plant species: Part 7a Dicotyledon families Nyctaginaceae to Primulaceae". Cunninghamia. 6 (2): 1075. Retrieved 2 February 2023.
  9. ^ McGillivray, D. J.; Makinson, R.O. (1993). Grevillea, Proteaceae: a taxonomic revision. Melbourne University Press. pp. 217, 218. ISBN 0522844391.{{cite book}}: CS1 maint: location missing publisher (link)
  10. ^ "Grevillea shiressii". APNI. Retrieved 2 February 2023.
  11. ^ a b Blakely, William F. (1925). "Contributions to our Knowledge of the Flora of New South Wales". Proceedings of the Linnean Society of New South Wales. 50 (4): 383–384. Retrieved 2 February 2023.
  12. ^ a b "Grevillea shiressii - profile". New South Wales Government Office of Environment and Heritage. Retrieved 2 February 2023.
  13. ^ "Approved Conservation Advice for Grevillea shiressii" (PDF). Australian Government Department of Climate Change, Environment, Energy and Water. Retrieved 2 February 2023.