Casuarina equisetifolia
Casuarina equesitifolia tree.jpg
C. equisetifolia subsp. incana
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fagales
Family: Casuarinaceae
Genus: Casuarina
C. equisetifolia
Binomial name
Casuarina equisetifolia
  • C. e. subsp. equisetifolia
  • C. e. subsp. incana
C. equisetifolia tree at Mahamaya Lake
C. equisetifolia tree at Chikhaldara, Maharashtra
Branches and fruits
C. equisetifolia - MHNT

Casuarina equisetifolia, common names Coastal She-oak or Horsetail She-oak[1] (sometimes referred to as the Australian pine tree or whistling pine tree outside Australia), is a she-oak species of the genus Casuarina. The native range extends throughout Southeast Asia, Northern Australia and the Pacific Islands; including Thailand, Myanmar, Vietnam, Malaysia, Singapore, Brunei, Indonesia, East Timor, and the Philippines (where it is known as agoho pine),[2] east to Papua New Guinea, French Polynesia, New Caledonia, and Vanuatu, and south to Australia (north of Northern Territory, north and east Queensland, and north-eastern New South Wales).[3] Populations are also found in Madagascar, but it is doubtful if this is within the native range of the species.[4][5] The species has been introduced to the Southern United States and West Africa.[6] It is an invasive species in Florida,[7][8] South Africa, India and Brazil.[9]


Casuarina equisetifolia was officially described by Linnaeus in 1759 as Casuarina equisetifolia. A type was designated by New South Wales botanist Lawrie Johnson in 1989.[10] The specific name equisetifolia is derived from the Latin equisetum, meaning "horse hair" (referring to the resemblance of the drooping branchlets to horse tail).[3] Common names include coast sheoak (coast she oak, coastal she-oak), beach casuarina, beach oak, beach sheoak (beach she-oak), beach pine, whistling tree, horsetail she oak, horsetail beefwood, horsetail tree, Australian pine, ironwood, whistling pine, Filao tree, and agoho.[3][10][5]

There are two subspecies:[11][12]

  • Casuarina equisetifolia subsp. equisetifolia. Large tree to 35 m (115 ft) tall; twigs 0.5–0.7 mm (0.020–0.028 in) diameter, hairless. Southeast Asia, northern Australia.[13]
  • Casuarina equisetifolia subsp. incana (Benth.) L.A.S.Johnson. Small tree to 12 m (39 ft) tall; twigs 0.7–1 mm (0.028–0.039 in) diameter, downy. Eastern Australia (eastern Queensland, New South Wales), New Caledonia, southern Vanuatu.[14]
Casuarina equisetifolia leaf litter suppresses germination of understory plants using a biochemical means or allelopathy. This is one reason it can be such a damaging invasive species in places outside its native range.


Tree and leaves

Casuarina is an evergreen tree growing to 6–35 m (20–115 ft) tall. The foliage consists of slender, much-branched green to grey-green twigs 0.5–1 mm (0.020–0.039 in) diameter, bearing minute scale-leaves in whorls of 6–8.

Like some other species of the genus Casuarina, C. equisetifolia is an actinorhizal plant able to fix atmospheric nitrogen.[15] In contrast to species of the plant family Fabaceae (e.g., beans, alfalfa, Acacia), Casuarina harbours a symbiosis with a Frankia actinomycete.[citation needed]


The flowers are produced in small catkin-like inflorescences; the male flowers in simple spikes 0.7–4 cm (0.28–1.57 in) long, the female flowers on short peduncles. Unlike most other species of Casuarina (which are dioecious) it is monoecious, with male and female flowers produced on the same tree.[4][16]


The fruit is an oval woody structure 10–24 mm (0.39–0.94 in) long and 9–13 mm (0.35–0.51 in) in diameter, superficially resembling a conifer cone made up of numerous carpels each containing a single seed with a small wing 6–8 mm (0.24–0.31 in) long.[4][16]

When these fruits ripen, they turn brown and open, dispersing the seeds by water. The seeds can only grow in hot sand near the seashore. Those seeds sprout and form thickets.[15]

Distribution and habitat

Casuarina is found from Myanmar and Vietnam throughout Malesia east to French Polynesia, New Caledonia, and Vanuatu, and south into Australia (the northern parts of Northern Territory, north and east Queensland, and northeastern New South Wales, where it extends as far south as Laurieton.[17]


Casuarina is widely used as a bonsai subject, particularly in South-east Asia and parts of the Caribbean. Indonesian specimens and those cultivated in Taiwan are regarded among the best in the bonsai world. The wood of this tree is used for shingles, fencing, and is said to make excellent hot-burning firewood. Among the islands of Hawaii, Casuarina are also grown for erosion prevention, and in general as wind breaking elements.[citation needed]

The Casuarina leaves are usually used for ornamental purposes in the urban region.[citation needed]

Other than ornamental purposes, the Casuarina was also explored in for its potential in remediation of textile dye wastewater. Casuarina leaves were found to be useful as absorbent material for the removal of textile dyes such as reactive orange 16[18] Rhodamine B,[19] methylene blue, malachite green[20] and methyl violet 2b.[21] Similarly the Casuarina dried cone was also reported to be able to remove Rhodamine B,[22] and methyl violet 2b.[23] The Casuarina bark was reported to able to remove methylene blue.[24] Even the Casuarina seed was also found to be useful in dye removal of neutral red and malachite green.[25] The carbon derived from the cones of Casuarina was found to be good absorbent for the landfill leachate,[26] while another laboratory also reported good absorbent for copper ions from aqueous solution.[27] Casuarina equisetifolia Lin. (Casuarinaceae) has been used traditionally for treating inflammation, cancer and other diseases, but its efficacy has not been scientifically examined in treating arthritis; the bark extract showed anti-arthritic activity.[citation needed] Methanolic extract of Casuarina equisetifolia fruit contain significant percentage of secondary metabolite like poly phenol, it showed antioxidant and anti-arthritic activity.[citation needed] Methanolic extract of Casuarina equisetifolia Lin. Leaf against Ehrlich Ascites Carcinoma Induced Cancer in Mice; possess protective action on the hemopoietic system.[citation needed]

Relationship with humans

Names of places

There are many places in South Asia and Southeast Asia named after this plant. In Sri Lanka, a famous beach on the Jaffna Peninsula, Casuarina Beach, is named because of the many Casuarina trees that line the coast. Casuarina is known as ru, rhu or aru in Malay. Many coastal fisherman villages in Terengganu have names such as Ru Renggeh,[28] Ru Dua,[29] Rusila formerly Ru Se Le (Ru Satu Pokok Sahaja "Just One Casuarina Tree"), and Ru Rendang.

There are many places named because they have a cape (tanjung) where casuarina trees grow there. In Singapore, there is a road named Tanjong Rhu Road because it once had many of these trees growing along the coast from Kallang to Rochor.[30] In the island of Langkawi, Kedah, Malaysia, there is a sand spit in the mouth of the Ayer Hangat river in the Kilim Karst Geoforest Park about 20 km from the town of Kuah also named Tanjung Rhu where these trees line here.[31] The town of Tanjung Aru in Sabah is also named because a lot of this tree (aru) is found in its beach.[32]


The legendary miraculous spear Kaumaile came with the hero Tefolaha on the South Pacific island Nanumea. He fought with it on the islands of Samoa and Tonga. As Tefolaha died, "Kaumaile" went to his heirs, then to their heirs, and on and on - 23 generations. It is about 1.80 meters long and about 880 years old and the tree was cut on Samoa.[33]


See also

  • Pinus kesiya, the Khasi or Benguet pine


  1. ^ "NEW SOUTH WALES FLORA ONLINE: Casuarina equisetifolia L." PlantNET, National Herbarium of NSW. Retrieved 2022-04-16.
  2. ^ "Agoho". The Trees of Alabang Hills, Muntinlupa, Philippines. Archived from the original on 2 March 2019. Retrieved 12 March 2019.
  3. ^ a b c Boland, D. J.; Brooker, M. I. H.; Chippendale, G. M.; McDonald, M. W. (2006). Forest trees of Australia (5th ed.). Collingwood, Vic.: CSIRO Publishing. p. 82. ISBN 0-643-06969-0.
  4. ^ a b c "Casuarina equisetifolia L., Amoen. Acad. 143 (1759)" (PDF). Flora of Australia (volume 3) Hamamidales to Casuarinales. Australian Government Publishing Service. 1989. p. 104. Retrieved 2022-04-16.
  5. ^ a b "Casuarina equisetifolia". AgroForestryTree Database. Archived from the original on 2012-07-31. Retrieved 2011-10-12.
  6. ^ "Plant for the Planet: Billion Tree Campaign" (PDF). United Nations Environment Programme. February 2008. Archived from the original (PDF) on 17 May 2011. Retrieved 23 April 2011.
  7. ^ "Biological control of Australian native Casuarina species in the USA". Commonwealth Scientific and Industrial Research Organisation. 16 May 2007. Archived from the original on 5 June 2011. Retrieved 16 September 2010.
  8. ^ Masterson, J (4 October 2007). "Casuarina equisetifolia (Australian Pine)". Fort Pierce: Smithsonian Marine Station. Archived from the original on 2 July 2009. Retrieved 5 May 2009.
  9. ^ "SANBI:Declared Weeds & Invader Plants". South African National Biodiversity Institute. Archived from the original on 2014-10-06. Retrieved 25 September 2014.
  10. ^ a b "Casuarina equisetifolia L." Australian Plant Name Index (APNI), IBIS database. Centre for Plant Biodiversity Research, Australian Government.
  11. ^ "APC: Casuarina equisetifolia". Vascular Plants. 13 July 2021. Retrieved 14 July 2021.{{cite web}}: CS1 maint: url-status (link)
  12. ^ "Casuarina equisetifolia". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 23 April 2011.
  13. ^ "Casuarina equisetifolia L. subsp. equisetifolia". Australian Biological Resources Study. Australian National Botanic Gardens. Archived from the original on 18 May 2008. Retrieved 23 April 2011.
  14. ^ "Casuarina equisetifolia subsp. incana". Australian Biological Resources Study. Australian National Botanic Gardens. Archived from the original on 18 May 2008. Retrieved 23 April 2011.
  15. ^ a b Tan, Ria (October 2016). "Rhu or Casuarina tree". Wild Singapore. Retrieved 25 October 2022.
  16. ^ a b Huxley, Anthony; Griffiths, Mark; Levy, Margot (1992). The New Royal Horticultural Society dictionary of gardening. Volume 1. London: Macmillan. ISBN 0-333-47494-5.
  17. ^ K. L. Wilson & L. A. S. Johnson. "New South Wales Flora Online: Casuarina equisetifolia". Royal Botanic Gardens & Domain Trust, Sydney, Australia.
  18. ^ "Biodegradation of reactive orange 16 (RO-16) dye in packed bed bioreactor using seeds of Ashoka and Casuarina as packing medium". Indian Journal of Biotechnology. 16 (2): 216–221. April 2017. Archived from the original on 30 October 2017 – via NISCAIR Online Periodicals Repository.
  19. ^ Kooh, Muhammad Raziq Rahimi; Dahri, Muhammad Khairud; Lim, Linda B.L. (2016). "The removal of rhodamine B dye from aqueous solution using Casuarina equisetifolia needles as absorbent". Cogent Environmental Science. 2. doi:10.1080/23311843.2016.1140553.
  20. ^ Dahri, Muhammad Khairud; Kooh, Muhammad Raziq Rahimi; Lim, Linda B.L. (2015). "Application of Casuarina equisetifolia needle for the removal of methylene blue and malachite green dyes from aqueous solution". Alexandria Engineering Journal. 54 (4): 1253. doi:10.1016/j.aej.2015.07.005.
  21. ^ Dahri, Muhammad Khairud; Kooh, Muhammad Raziq Rahimi; Lim, Linda B. L. (2013). "Removal of Methyl Violet 2B from Aqueous Solution Using Casuarina equisetifolia Needle". ISRN Environmental Chemistry. 2013: 1–8. doi:10.1155/2013/619819.
  22. ^ Dahri, Muhammad Khairud; Kooh, Muhammad Raziq Rahimi; Lim, Linda B. L. (2016). "Remediation of Rhodamine B Dye from Aqueous Solution Using Casuarina equisetifolia Cone Powder as a Low-Cost Absorbent". Advances in Physical Chemistry. 2016: 1–7. doi:10.1155/2016/9497378.
  23. ^ "Water remediation using Casuarina equisetifolia cone as adsorbent for the removal of methyl violet 2B dye using batch experiment method". Journal of Environment & Biotechnology Research. 6 (1): 34–42. January 2017. Archived from the original on 19 March 2017 – via ViNaNiE.
  24. ^ "Adsorption of methylene blue by casuarina equisetifolia bark". {{cite journal}}: Cite journal requires |journal= (help)
  25. ^ "Application of microwave-treated Casuarina equisetifolia seeds in adsorption of dyes". Journal of Fundamental and Applied Sciences. 9: 458–471. 2017. doi:10.4314/JFAS.V9I7S.43 (inactive 31 December 2022). ISSN 1112-9867.{{cite journal}}: CS1 maint: DOI inactive as of December 2022 (link)
  26. ^ Alrozi, Rasyidah; Zubir, Nor Aida; Kamaruddin, Mohamad Anuar; Yusof, Siti Noor Faizah Mohd; Yusoff, Mohd Suffian (2017). "Removal of organic fractions from landfill leachate by Casuarina equisetifolia activated carbon: Characteristics and absorption mechanisms". AIP Conference Proceedings. 1885 (1): 020139. Bibcode:2017AIPC.1885b0139A. doi:10.1063/1.5002333.
  27. ^ Muslim, A. (2017). "AUSTRALIAN PINE CONES-BASED ACTIVATED CARBON FOR ADSORPTION OF COPPER IN AQUEOUS SOLUTION" (PDF). Journal of Engineering Science and Technology. 12 (2): 280–295.
  28. ^ 3, Kampung Ru Renggeh, 21080 Kuala Terengganu, Terengganu, Malaysia
  29. ^ Kampong Ru Dua Map — Satellite Images of Kampong Ru Dua
  30. ^ Thulaja, Naidu Ratnala (24 January 2018) [31 December 2004]. "Tanjong Rhu Road". Infopedia. Government of Singapore. Retrieved 25 October 2022.
  31. ^ "Tanjung Rhu". Kilim Geoforest Park. The Cooperative of Kilim Village Community Langkawi Limited. 2022. Retrieved 25 October 2022.
  32. ^ "'Replant Aru trees, mangroves at Tanjung Aru blaze site' call". Daily Express. 22 July 2021. Retrieved 25 October 2022.
  33. ^ Franz, Angelika (30 May 2014). "Hamburger Forscher löst Rätsel um Südsee-Speer". Spiegel Online (in German). Archived from the original on 6 October 2014. Retrieved 25 September 2014.

External links

  • NT Flora: Casuarina equisetifolia. Northern Territory Government.

Shopping cart


Cart empty

Login Form