Casuarina, also known as she-oak, Australian pine[3][4][5] and native pine,[6] is a genus of flowering plants in the family Casuarinaceae, and is native to Australia, the Indian subcontinent, Southeast Asia, islands of the western Pacific Ocean, and eastern Africa.

Casuarina
Casuarina equisetifolia, showing red female flowers and mature fruits
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fagales
Family: Casuarinaceae
Genus: Casuarina
L.[1]
Type species
Casuarina equisetifolia[2]
L.
Species

See text

Female cones of C. equisetifolia

Plants in the genus Casuarina are monoecious or dioecious trees with green, pendulous, photosynthetic branchlets, the leaves reduced to small scales arranged in whorls around the branchlets, the male and female flowers arranged in separate spikes, the fruit a cone containing grey or yellowish-brown winged seeds.

Description

edit

Plants in the genus Casuarina are dioecious trees (apart from C. equisetifolia that is monoecious), with fissured or scaly greyish-brown to black bark. They have soft, pendulous, green, photosynthetic branchlets, the leaves reduced to scale-like leaves arranged in whorls of 5 to 20 around the branchlets. The branchlets are segmented at each whorl with deep furrows that conceal the stomates. Male flowers are arranged along branchlets in spikes with persistent bracteoles, female flowers in spikes on short side-branches (effectively "peduncles") that differ in appearance from vegetative branchlets. After fertilisation, the female spikes develop into "cones" with thin, woody bracteoles that extend well beyond the cone body. The cones enclose grey or yellowish-brown winged seed known as samaras.[7][8][9][10][11][12]

Ecology

edit

Casuarina are attacked by a range of herbivorous insects.

Taxonomy

edit

The genus Casuarina was first formally described in 1759 by Carl Linnaeus in Amoenitates Academicae and the first species he described (the type species) was Casuarina equisetifolia.[2][18] The generic name is derived from the Malay word for the cassowary, kasuari, alluding to the similarities between the bird's feathers and the plant's foliage.[19]

Species List

edit

The following is a list of Casuarina species accepted by Plants of the World Online as of April 2023:[20]

In 1982, Lawrence Johnson raised the genera Allocasuarina and Gymnostoma in the Journal of the Adelaide Botanic Gardens, and transferred some species previously included in Casuarina to the new genera. The species of Allocasuarina previously in Casuarina are: A. acuaria, A. acutivalvis, A. campestris, A. corniculata, A. decaisneana, A. decussata, A. dielsiana, A. distyla, A. drummondiana, A. drummondiana, A. fraseriana, A. grevilleoides, A. helmsii, A. huegeliana, A. humilis, A. inophloia, A. lehmanniana subsp. lehmanniana, A. littoralis, A. luehmannii, A. microstachya, A. monilifera, A. muelleriana, A. nana, A. paludosa, A. paradoxa, A. pinaster, A. pusilla, A. ramosissima, A. rigida, A. robusta, A. striata, A. tessellata, A. thuyoides, A. torulosa, A. trichodon and A. verticillata. The species of Gymnostoma previously included in Casuarina are G. chamaecyparis, G. deplancheanum, G. intermedium, G. leucodon, G. nobile, G. nodiflorum, G. papuanum, G. poissonianum, G. rumphianum and G. sumatranum and G. webbianum.[21]

Invasive species

edit
 
Casuarina on Gold Rock Beach, Grand Bahama

C. cunninghamiana, C. glauca and C. equisetifolia have become naturalized in many countries, including Argentina, Bermuda, Cayman Islands, Cuba, China, Egypt, Israel, Iraq, Mauritius, Kenya, Mexico, Brazil, South Africa, the Bahamas,[22] and Uruguay. They are considered an invasive species[23][24] in the United States, especially in southern Florida[25] where they have nearly quadrupled in number between 1993 and 2005 and are called the Australian pine.[3] C. equisetifolia is widespread in the Hawaiian Islands where it grows both on the seashore in dry, salty, calcareous soils and up in the mountains in high rainfall areas on volcanic soils.[citation needed] It is also an invasive plant in Bermuda, where it was introduced to replace the Juniperus bermudiana windbreaks killed by a scale insect in the 1940s.[26]

References

edit
  1. ^ "Casuarina". Plants of the World Online. Retrieved 21 April 2023.
  2. ^ a b "Casuarina". APNI. Retrieved 21 April 2023.
  3. ^ a b IFAS: SRFer Mapserver Archived 2007-09-07 at the Wayback Machine
  4. ^ a b "Evaluating Biological Control Agents of Australian Pine : USDA ARS". www.ars.usda.gov. Retrieved 2023-07-20.
  5. ^ "FIELD GUIDE TO IDENTIFY THE COMMON CASUARINA (AUSTRALIAN PINE) SPECIES IN FLORIDA". Institute of Food and Agricultural Sciences. University of Florida. Retrieved 2023-09-12.
  6. ^ "Casuarina glauca prostrate forms". Australian National Botanic Gardens. Australian National Biodiversity Research. Retrieved 2023-09-12.
  7. ^ Wilson, Karen L.; Johnson, Lawrence A.S. George, Alex S. (ed.). "Casuarina". Australian Biological Resources Study, Department of Climate Change, the Environment and Water: Canberra. Retrieved 22 April 2023.
  8. ^ "Casuarina". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions.
  9. ^ Wilson, Karen L.; Johnson, Lawrence A.S. Wilson, Karen L. (ed.). "Genus Casuarina". Royal Botanic Garden Sydney. Retrieved 22 April 2023.
  10. ^ Entwisle, Timothy J.; Walsh, Neville. "Casuarina". Royal Botanic Gardens Victoria. Retrieved 22 April 2023.
  11. ^ "Casuarina". Northern Territory Government. Retrieved 22 April 2023.
  12. ^ Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan Publishers. ISBN 0-333-47494-5.
  13. ^ a b c "Ecology and Management of Sheoak (Casuarina spp.), an Invader of Coastal Florida, U.S.A." (PDF). Journal of Coastal Research. 27 (3): 485. 2011-05-01. doi:10.2112/JCOASTRES-D-09-00110.1. ISSN 0749-0208. S2CID 55348868.
  14. ^ Fisher, Nicole; Moore, Aubrey; Brown, Bradley; Purcell, Matthew; Taylor, Gary S.; Salle, John La (2014-04-23). "Two new species of Selitrichodes (Hymenoptera: Eulophidae: Tetrastichinae) inducing galls on Casuarina (Casuarinaceae)". Zootaxa. 3790 (4): 534–542. doi:10.11646/zootaxa.3790.4.2. ISSN 1175-5334. PMID 24869885.
  15. ^ Taylor, Gary S.; Austin, Andy D.; Jennings, John T.; Purcell, Matthew F.; Wheeler, Gregory S. (2010-09-02). "Casuarinicola, a new genus of jumping plant lice (Hemiptera: Triozidae) from Casuarina (Casuarinaceae)". Zootaxa. 2601 (1): 1. doi:10.11646/zootaxa.2601.1.1. ISSN 1175-5334.
  16. ^ Hodgson, Chris; Mille, Christian; CazèRes, Sylvie (2014-03-05). "A new genus and species of felt scale (Hemiptera: Coccoidea: Eriococcidae) from New Caledonia". Zootaxa. 3774 (2): 152–164. doi:10.11646/zootaxa.3774.2.3. ISSN 1175-5334. PMID 24871412.
  17. ^ Kolesik, Peter; Brown, Bradley T; Purcell, Matthew F; Taylor, Gary S (2012). "A new genus and species of gall midge (Diptera: Cecidomyiidae) from Casuarina trees in Australia: New gall midge from Casuarina". Australian Journal of Entomology. 51 (4): 223–228. doi:10.1111/j.1440-6055.2012.00860.x.
  18. ^ Linnaeus, Carl (1759). Amoenitates academicae, seu, Dissertationes variae physicae, medicae, botanicae. p. 143. Retrieved 21 April 2023.
  19. ^ Quattrocchi, Umberto (2000). CRC World Dictionary of Plant Names. Vol. I A-C. CRC Press. p. 456. ISBN 978-0-8493-2675-2.
  20. ^ Govaerts R. "Casuarina L.". Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. Retrieved 20 April 2023.
  21. ^ Johnson, Lawrence A. (1982). "Note on Casuarinaceae II". Journal of the Adelaide Botanic Gardens. 6 (1): 73–86. Retrieved 21 April 2023.
  22. ^ BEST Commission (March 2003). "The National Invasive Species Strategy for The Bahamas". Nassau, The Bahamas: BEST. Archived from the original on 2011-07-06.
  23. ^ USFS FEIS: Casuarina
  24. ^ USDA Forest service: Casuarina Archived 2013-02-11 at the Wayback Machine
  25. ^ "GISD". www.iucngisd.org.
  26. ^ "Casuarina (Casuarina equisetifolia)". Department of Conservation. Government of Bermuda. Archived from the original on 2010-03-05. Retrieved 2010-10-01.
edit