Acacia gunnii, commonly known as ploughshare wattle[1] or dog's tooth wattle,[1] is a woody shrub which is endemic to south-eastern Australia found in dry heaths and woodlands.[2][3] It ranges from Queensland, then New South Wales, Australian Capital Territory, Victoria, South Australia, down to Tasmania.[2] Acacia gunnii grows to up to 1 metre high and has prickly phyllodes which are 4 to 15 mm long. The cream to pale yellow globular flowerheads appear singly in the axils of the phyllodes in June to October, followed by curved or coiled seed pods which are 40 mm long and 4 to 5 mm wide.[4][5] Acacia gunnii grows up to 1 meter tall and has prickly phyllodes which are 4 to 15mm in length with cream to pale-yellow globular flower heads appearing in phyllode axils in June through to October, followed by curved or coiled seed pods which are 40mm long and 4 to 5 mm wide.[6][7] The species was first formally described by English botanist George Bentham in the London Journal of Botany in 1842.[4] It occurs in South Australia, Victoria, Tasmania, New South Wales, Australian Capital Territory, and Queensland.[4]

Ploughshare wattle
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Caesalpinioideae
Clade: Mimosoid clade
Genus: Acacia
Species:
A. gunnii
Binomial name
Acacia gunnii
Occurrence data from AVH
Synonyms
  • Acacia gunnii var. angustifolia Benth.
  • Acacia gunnii var. hirsutior Benth.
  • Acacia vomeriformis A.Cunn. ex Benth.
  • Racosperma gunnii (Benth.) Pedley

Description edit

Acacia gunnii is a woody decumbent to erect shrub up to 1 meter in height, branchlets are terete usually covered with stiff hairs.[6][3] Dark green phyllodes are asymmetric, can be sessile, variable in shape usually with a pronounced gland on adaxial margin near or below middle.[6][8] Phyllodes are 4-15mm long and 1.4-4mm across and appear glabrous or finely haired with a prominent mid-vein, sometimes the apex pungent pointed.[6][8]

Inflorescences are simple with 1 in the axis of phyllodes, peduncles are hairy, 4–15 mm in length with the head being globose, 20-30 flowered, cream to yellow coloured, and 5-8mm in diameter.[8]

Pods are more or less straight being 40mm long and 4-5mm in width, dark brown to black containing longitudinal to oblique seeds. Pods are chartaceous to coriaceous, glaberous and occasionally are covered in hair.[8][6]

Taxonomy edit

The species was first formally described by English botanist George Bentham in the London Journal of Botany in 1842.[9]

Botanical Classification edit

Acacia gunnii is a member of the plant genus Acacia, commonly known as the Wattle's, which belong to the sub-family Mimosoidea, which is under the family Fabaceae.[10][11] Globally there are approximately 1350 Acacia species, and they are the largest group of Australian vascular plants with near 1000 different species.[10][12]

The Fabaceae family is split into three distinct sub-families:

However, recent studies have shown that a new classification system consisting of six sub-families within Fabaceae is possible, and under such classification system the genus Acacia isincluded in the sub-family Caesalpinioideae,[12][11] however this is yet to be adopted by the Australasian Virtual Herbarium.

Hybrids with other species edit

Acacia gunnii is reported to have hybridised with Acacia ulicifolia and Acacia brownii in New South Wales and Victoria which has resulted in specimens with elongated phyllodes and with a much reduced gland angle.[6][13] Possible hybrids with elongated phyllodes occur in the same locations as the normal form for each species.[13]

Distribution and habitat edit

Acacia gunni is a widespread woody shrub species along the eastern seaboard of Australia. It is commonly found along the Great Divide and associated slopes from the Grampions, Victoria, through to near Stanthorpe in Queensland,[14] It is also found uncommonly in Tasmania.[3] Acacia gunnii occurs on rocky hillsides and amongst rock outcrops in open dry sclerophyll forest usually mainly composed ofEucalyptus olbliqua and Eucalyptus baxteri as the dominant Eucalyptus species.[14][8] It is generally associated with sandy loam soils where rainfall is around 500 – 1000 mm per annum.[14] It is most abundant in regions of partially disturbed and open rocky habitat with sparse understory, commonly, along track/road edges.[14]

References edit

  1. ^ a b c "Acacia gunnii Benth". Australian Plant Name Index. Australian National Botanic Gardens. Retrieved 31 August 2010.
  2. ^ a b "Acacia gunnii". PlantNET - New South Wales Flora Online. Royal Botanic Gardens & Domain Trust, Sydney Australia. Retrieved 31 August 2009.
  3. ^ a b c "Key to Tasmanian Dicots". www.utas.edu.au. Retrieved 21 February 2023.
  4. ^ a b c "ABRS Flora of Australia Online Search Results: Acacia gunnii". Flora of Australia Online. Australian National Botanic Gardens. Archived from the original on 26 October 2012. Retrieved 29 March 2014.
  5. ^ Wild Plants of Victoria (database). Viridans Biological Databases & Department of Sustainability and Environment. 2009.
  6. ^ a b c d e f "Flora of Victoria". vicflora.rbg.vic.gov.au. Retrieved 21 February 2023.
  7. ^ "Australian National Botanic Gardens - Growing Acacia". www.anbg.gov.au. Retrieved 21 February 2023.
  8. ^ a b c d e "PlantNET - FloraOnline". plantnet.rbgsyd.nsw.gov.au. Retrieved 21 February 2023.
  9. ^ "Fact sheet for Acacia gunnii". www.flora.sa.gov.au. Retrieved 11 March 2023.
  10. ^ a b Australian National Botanic Gardens, Parks Australia. "Wattles, genus Acacia - Australian Plant Information". www.anbg.gov.au. Retrieved 21 February 2023.
  11. ^ a b "New Subfamily Classification of the Leguminosae and Insights into Plastomes of the Mimosoid Clade----Chinese Academy of Sciences". english.cas.cn. Retrieved 21 February 2023.
  12. ^ a b c "Acacia". Australian Native Plants Society (Australia). Retrieved 21 February 2023.
  13. ^ a b "Factsheet - Acacia gunnii". apps.lucidcentral.org. Retrieved 21 February 2023.
  14. ^ a b c d "Acacia gunnii" (PDF). Adelaide and Mount Lofty Ranges: Threatened species list. May 2008. Retrieved 21 February 2003.