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Opuntia is a genus in the cactus family Cactaceae. Both prickly pears and chollas are included in this genus of about 250 species distributed throughout most of the New World. The type species of the genus is the Indian fig opuntia Opuntia ficus-indica (most culinary uses of the term 'prickly pear' are referring to that plant).
Description Prickly pears, classified in the subgenus Opuntia, typically grow with flat, rounded segments that are armed with two kinds of spines; large, smooth, fixed spines and small, almost hairlike spines called glochids that easily penetrate skin and detach from the plant. Many types of prickly pear can grow into dense, tangled structures. Prickly pears species are found in abundance in the West and Southwest of the United States and throughout much of Mexico. Prickly pears are also the only types of cactus normally found in the eastern United States. They are the most cold-tolerant of the cacti, extending north into southern Canada. One species, Opuntia fragilis var. fragilis, extends into northern Canada and has been found growing along the Beatton River in the province of Alberta, southwest of Cecile Lake at 56° 17’ N latitude and 120° 39’ W longitude. Chollas, classified in the subgenus Cylindropuntia, are distinguished by having cylindrical, not flattened, stem segments, with the large spines barbed. Some botanists treat Cylindropuntia as a distinct genus. The stem joints of several species, notably the jumping cholla (Opuntia fulgida), are very brittle on young stems, readily breaking off when the barbed spines stick to clothing or animal skin. This helps distribute the cholla because when the stem falls off the person or animal, it takes root and grows where it falls. The barbed spines often remain embedded in the skin, causing significant discomfort and sometimes injury. The fruit of opuntias, called tuna, is edible, although it has to be peeled carefully to remove the small spines on the outer skin before consumption. It is often used to make candies and jelly. The young stem segments, called nopales, are also edible. The fruit is a favourite in Sicilian cuisine, where it is called ficcudinia which is literally translated as Indian fig. The gel-like liquid of a prickly pear cactus can be used like a conditioner. Prickly pears also have medicinal uses. They are said to control blood sugar, cure acne, and soothe skin, and can also be used as arthritis medicine and eye drops. Prickly pears in Europe Opuntia littoralis has been introduced to Europe and flourishes in areas with a suitable climate, such as the south of France. Prickly pears in Australia Prickly pears (mostly O. stricta) were imported into Australia in the 19th century for use as a natural agricultural fence and to establish a cochineal dye industry. They quickly became a widespread weed, rendering 40,000 km² of farming land unproductive. The Cactoblastis moth, a South American moth whose larvae eat prickly pear, was introduced in 1925 and almost wiped out the infestation. This case is often cited as a "textbook" example of successful biological pest control. The same moth, introduced accidentally further north of its native range into southern North America, is causing serious damage to some native species in that area. Opuntia as a host for Dactylopius coccus These scale insects (the females) are used in the production of cochineal. Example species
Synonymy The following genera are included in in the genus Opuntia: Sources W.P. Fraser Herbarium from Cota-Sanchez, H. 2002. Taxonomy, distribution, rarity status and uses of Canadian Cacti. Haseltonia 9: 17-25. Retrieved January 10, 2006. Establishes the northernmost range of Opuntia. | |||||||||||||||||||||||||||||||||||||
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