Cholla cactus

Cholla
Cylindropuntia kleiniae
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Caryophyllales
Family:	Cactaceae
Subfamily:	Opuntioideae
Tribe:	Cylindropuntieae
Genus:	Cylindropuntia (Engelm.) F.M.Knuth
Species
Numerous, see text

Numerous, see text

Cylindropuntia is a genus of cacti (family Cactaceae), containing the cholla, native to northern Mexico and the Southwestern United States. They are known for their barbed spines that tenaciously attach to skin, fur, and clothing.

Stands of cholla are called cholla gardens. Individuals within these colonies often exhibit the same DNA as they were formerly tubercles of an original plant.

Cylindropuntia was formerly treated as a subgenus of Opuntia, but have now been separated based on their cylindrical stems (Opuntia species have flattened stems) and the presence of papery epidermal sheaths on the spines (Opuntia has no sheaths). A few species of mat- or clump-forming opuntioid cacti are currently placed in the genus Grusonia. Collectively, opuntias, chollas, and related plants are sometimes called opuntiads.

The roughly 35 species of Cylindropuntia are native to the southwest and southcentral United States, Mexico, and the West Indies. The Flora of North America recognizes 22 species. Some species have been introduced to South America (Chile, Ecuador, Peru) and South Africa.

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