Casuarina equisetifolia, commonly known as coastal she-oak, horsetail she-oak, ironwood, beach sheoak, beach casuarina, whistling tree or Australian pine is a species of flowering plant in the family Casuarinaceae and is native to Australia, New Guinea, Southeast Asia and India. It is a small to medium-sized, monoecious tree with scaly or furrowed bark on older specimens, drooping branchlets, the leaves reduced to scales in whorls of 7 or 8, the fruit 10–24 mm (0.4–0.9 in) long containing winged seeds (samaras) 6–8 mm (0.2–0.3 in) long.
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👉 Casuarina equisetifolia in the context of Tupua'i
Tupuaʻi (French: Tubuai [tubwaj]) is the main island of the Austral Island group, located 640 km (400 mi) south of Tahiti. In addition to Tubuai, the group of islands include Rimatara, Rurutu, Raivavae, Rapa and the uninhabited Îles Maria. They are part of the Austral Islands in the far southwest of French Polynesia in the south Pacific Ocean. Tubuai island sustains a population of 2,185 people on 45 km (18 sq. mi.) of land. Due to its southerly position, Tubuai has notably cooler weather than Tahiti.
The island is ringed by a lagoon formed by an encircling coral reef. A break in the reef that enables passage for ships is located on the north side of the island. Tubuai has two lava domes, with its highest point, Mt Taita'a, being 422 meters (1385 feet). Six or seven islets or motus lie along the reef rim that encircles the island. These were described in the late 1700s as having an abundance of toa trees (Casuarina equisetifolia), which the indigenous peoples used in house building and to make war clubs and spears due to the wood's density.
In this Dossier
- ⭐ Core Definition: Casuarina equisetifolia
- 👉 Casuarina equisetifolia in the context of Tupua'i
- Casuarina equisetifolia in the context of Allelopathy
Casuarina equisetifolia in the context of Allelopathy
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have beneficial (positive allelopathy) or detrimental (negative allelopathy) effects on the target organisms and the community. Allelopathy is often used narrowly to describe chemically mediated competition between plants; however, it is sometimes defined more broadly as chemically mediated competition between any type of organisms. The original concept developed by Hans Molisch in 1937 seemed focused only on interactions between plants, between microorganisms and between microorganisms and plants. Allelochemicals are a subset of secondary metabolites, which are not directly required for metabolism (i.e. growth, development and reproduction) of the allelopathic organism.
Allelopathic interactions are an important factor in determining species distribution and abundance within plant communities, and are also thought to be important in the success of many invasive plants. For specific examples, see black walnut (Juglans nigra), tree of heaven (Ailanthus altissima), black crowberry (Empetrum nigrum), spotted knapweed (Centaurea stoebe), garlic mustard (Alliaria petiolata), Casuarina/Allocasuarina spp., and nut grass (Cyperus rotundus).
View the full Wikipedia page for Allelopathy