A cactus (plural: cacti, cactuses, or cactus) is any member of the succulent plant family Cactaceae, native to the Americas. They are often used as ornamental plants, but some are also Crop (agriculture)|crop plants.
Cacti are distinctive and unusual plants, which are adapted to extremely arid and hot Natural environment|environments, showing a wide range of Anatomy|anatomical and Physiology|physiological features which conserve water. Their stems have expanded into green succulent structures containing the chlorophyll necessary for life and growth, while the leaves have become the spines for which cacti are so well known.
Cacti come in a wide range of shapes and sizes. The tallest is ''Pachycereus pringlei'', with a maximum recorded height of 19.2 m,<ref>Salak, M. (2000). In search of the tallest cactus. ''Cactus and Succulent Journal'' 72 (3).</ref> and the smallest is ''Blossfeldia liliputiana'', only about 1 cm diameter at maturity.<ref>[http://www.sbs.utexas.edu/mauseth/ResearchOnCacti/large%20photo%20Blossfeld%20liliput%20plants.htm Mauseth Cactus research: ''Blossfeldia liliputiana'']</ref> Cactus flowers are large, and like the spines and branches arise from areoles. Many cactus species are night blooming, as they are pollination|pollinated by nocturnal insects or small animals, principally moths and bats. Cacti's sizes range from small... read all