Cotyledon orbiculata

Pig's Ear
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Saxifragales
Family:	Crassulaceae
Genus:	Cotyledon
Species:	C. orbiculata
Binomial name
Cotyledon orbiculata
Synonyms
Cotyledon elata Cotyledon oblonga Cotyledon ovata Cotyledon ramosa

Cotyledon orbiculata, commonly known as Pig's Ear or Round-leafed Navel-wort, is a succulent plant belonging to the Cotyledon genus.

Description

C. orbiculata is an extremely variable species that grows to approximately 1.3 m (4.3 ft) in height.^[1] It has gray-green leaves that can be up to 13 by 7 cm (5.1 by 2.8 in) with a white powdery substance on them that helps reflect sunlight and conserve water.^[2] The shape of the leaves was thought to have a resemblance to a pig's ear, thus the common name.^[3] The bell-shaped flowers are small, usually less than 3 cm (1.2 in) in length, and droop from the top of a 60 cm (24 in) tall stalk.^[1] The flowers are usually orange-red but yellow varieties also exist.

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  Flower

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  Leaves

Distribution

Native to South Africa,^[1] it is popular in gardens in many countries. In the wild, it grows naturally in rocky outcrops in grassy shrubland and the Karoo region. In New Zealand, it is considered an invasive plant and is listed on the National Pest Plant Accord.^[4]

Uses

C. orbiculata has a number of medicinal uses. In South Africa, the fleshy part of the leaf is applied to warts and corns. Heated leaves are used as poultices for boils and other inflammations. Single leaves may be eaten as a vermifuge and the juice has been used to treat epilepsy.^[2]

However, the leaves contain a bufanolide called cotyledontoxin, which is toxic to sheep, goats, horses, cattle, poultry, and dogs, causing a condition known as cotyledonosis.^[5]

References

1. ^ ^{a b c} "Cotyledon orbiculata". University of Oklahoma Department of Botany & Microbiology. June 13, 2009. http://www.plantoftheweek.org/week217.shtml. Retrieved 2010-04-19. 
2. ^ ^{a b} Harris, Shireen. "Cotyledon orbiculata". South Africa National Biodiversity Institute. http://www.plantzafrica.com/plantcd/cotyledorbic.htm. Retrieved 2010-04-19. 
3. ^ Vandecasteele, Petra; Godard, Paul (2008). In Celebration of Fynbos. Struik. pp. 54–55. ISBN 1770074902. 
4. ^ "National Pest Plant Accord" (PDF). Ministry of Agriculture and Forestry. 2008. http://www.biosecurity.govt.nz/files/pests/plants/nppa/nppa-accord-manual.pdf. Retrieved 2010-04-19. 
5. ^ Wickens, G. E. (1998). Ecophysiology of economic plants in arid and semi-arid lands. Springer. p. 204. ISBN 3540521712. http://books.google.com/books?id=s8oSKa6_EB8C&pg=PA204&dq=Cotyledontoxin&hl=en&ei=ldzNS6WPDYeiswPeucSvDg&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDkQ6AEwATgK#v=onepage&q&f=false.