Cascabela thevetia

Captain Cook tree

 

Cascabela thevetia

(L.) Lippold 1980

pronounced: kas-kuh-BELL-uh thev-ETT-ee-uh

(Apocynaceae — the oleander family)

synonym — Thevetia peruviana

(Pers.) K.Schum. 1895

pronounced: thev-ETT-ee-uh per-oo-vee-AH-nuh

common names: Captain Cook Tree, yellow oleander

This shrub or small tree has for many years been known by the synonym, but the Kew Plant List now declaes that Cascabela thevetia is the acccepted name. Cascabela is the Latinized form of Cascabel, a Spanish word meaning 'Rattle'; thevetia was named for André Thévet, (1503–1590), a French Franciscan priest, explorer, cosmographer, writer and plant collector who travelled to Brazil and described the country, its aboriginal inhabitants and the historical episodes involved in the France Antarctique, a French settlement in Rio de Janeiro, in his book Peculiarities of France Antarctique. In the synonym, Peruviana means ‘of or from Peru’.

The term oleander refers to two plant species, Nerium oleander (common oleander), and Cascabela thevetia (yellow oleander). Both species contain chemicals called cardiac glycosides, that have effects similar to the prescription drug digoxin. dangerous 2Both species can be toxic when taken by mouth, with many documented reports of death.

In Queensland, the yellow oleander has been declared a class 3 noxious weed. It invades native vegetation, and its supply or sale is prohibited. It may need removal from environmentally sensitive areas. There is a great deal of it growing on the Magnetic Island.

The plant probably originates from Mexico and Central America. It is an evergreen tropical shrub or small tree that bears yellow or pale apricot trumpet-like flowers. These are fragrant, about 5 cm across in clusters, and the tree blooms over a long period.

The leaves are alternate, nearly sessile, about 10 cm long by less than 1 cm broad, lanceolate, dark green and glossy. The leaves are covered in a waxy coating to reduce water loss, as is typical in oleanders. The stem is green, turning silver-grey as it ages. The plant is normally only a couple of metres tall, but in favourable conditions it can be as tall as 6 m.

Its fruit is a capsule 2–3 cm in diameter, green, turning red then black as it ripens, and encases a large seed, whose casing is extremely hard. The fruit soon drops to the ground after ripening.

dangerous 2The tree contains a milky sap having in it a compound called thevetin that is used as a heart stimulant, but in its natural form it is extremely poisonous, as are all parts of the plant, particularly the seeds.

In Ghana and Uganda the wood is used to make tool handles and building poles. It is also used as fuel.

 

Information about medicinal qualities of plants, or about their use as medicines, is for interest only, and is not intended to be used as a guide for the treatment of medical conditions.

 

Photographs taken at Picnic Bay 2008, 2017
Page last updated 31st October, 2018