Opuntia fragilis
Encyclopedia
Opuntia fragilis, known by the common names brittle prickly pear and little prickly pear, is a prickly pear
cactus
native to much of North America
. It occurs in several Canadian provinces. It is known from farther north than any other cactus, occurring at as close as 8°south of the Arctic Circle
, (58°N latitude) in Alberta
. There is an isolated and possibly genetically unique population in Eastern Ontario
known as the "Kaladar Cactus".
.
Opuntia fragilis is a small, prostrate plant, rarely more than 4 inches high: joints tumid, fragile, easily detached, oval, elliptical, or subglobose, 1-2 in. long and nearly as thick as broad, bright green: areoles ¼-½ in. apart, with whitish wool and a few white to yellow bristles, which are much longer and more abundant on older joints; spines 1-4, occasionally a few small additional ones, weak, dark brown, the upper one usually longer and stronger than the others, rarely an inch in length: flowers greenish yellow, 1-1¼ inches wide: fruit ovate to subglobose. with few spines or bristles, mostly sterile, an inch or less long; seeds few and large. Rocky Mountain region from Canada to New Mexico.
Opuntia
Opuntia, also known as nopales or paddle cactus , is a genus in the cactus family, Cactaceae.Currently, only prickly pears are included in this genus of about 200 species distributed throughout most of the Americas. Chollas are now separated into the genus Cylindropuntia, which some still consider...
cactus
Cactus
A cactus is a member of the plant family Cactaceae. Their distinctive appearance is a result of adaptations to conserve water in dry and/or hot environments. In most species, the stem has evolved to become photosynthetic and succulent, while the leaves have evolved into spines...
native to much of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. It occurs in several Canadian provinces. It is known from farther north than any other cactus, occurring at as close as 8°south of the Arctic Circle
Arctic Circle
The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. For Epoch 2011, it is the parallel of latitude that runs north of the Equator....
, (58°N latitude) in Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
. There is an isolated and possibly genetically unique population in Eastern Ontario
Eastern Ontario
Eastern Ontario is a subregion of Southern Ontario in the Canadian province of Ontario which lies in a wedge-shaped area between the Ottawa River and St. Lawrence River...
known as the "Kaladar Cactus".
Description
Brittle Prickly Pear is a small decumbent cactus that grows to a maximum height of 10 centimeters (4 in). Both the common and scientific names refer to the easily detached stem segments. This is known to be a means of plant dispersalBiological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...
.
Opuntia fragilis is a small, prostrate plant, rarely more than 4 inches high: joints tumid, fragile, easily detached, oval, elliptical, or subglobose, 1-2 in. long and nearly as thick as broad, bright green: areoles ¼-½ in. apart, with whitish wool and a few white to yellow bristles, which are much longer and more abundant on older joints; spines 1-4, occasionally a few small additional ones, weak, dark brown, the upper one usually longer and stronger than the others, rarely an inch in length: flowers greenish yellow, 1-1¼ inches wide: fruit ovate to subglobose. with few spines or bristles, mostly sterile, an inch or less long; seeds few and large. Rocky Mountain region from Canada to New Mexico.
Subspecies and varieties
- Var. brachyarthra, Coult. A plant with more swollen joints, more numerous and stronger spines, smaller flowers and more spiny fruit Colorado, New Mexico.
- Var. caespitosa, Hort. Joints bright green, smaller and more crowded than in the type: flowers bright yellow. Colorado.
- Var. tuberiformis, Hort. Joints olive-green, bulbous-looking. Colorado.