|Etymology -Beleived to refer to a Greek region - Locris Opuntia with the town of Opus in Greece where other spiny plants grew.
Opuntia is the most widespread of all genera in the cactus family. The genus occurs naturally throughout North and South America from as far north as Canada, through the Caribbean, and down into Argentina. With man's help, however, this species can now be found world-wide where it has escaped cultivation and become naturalized even to the point of being classified as a noxious weed.
Opuntia are easily recognized by their flat paddle-shaped stem segments called cladodes that grow one on top of the other. The edge and flat surfaces of these cladodes are covered with areoles that always have tiny, easily detached spines called glochids. Many Opuntia species have large, formidable spines in addition to the glochids, but some are armed only with masses of glochids. These have the appearance of being soft or fuzzy, but anyone who does touch them immediatly regrets doing so. The small size of the glochids does not cause much pain, but is rather highly irritating. As such, these have been collected for use in the making of itching powder.
Opuntia flowers are typically yellow, sometimes pink, and rarely white or anywhere inbetween these colors. Flowers are cup-shaped and do not have floral tubes, but instead the pericarples resemble round, extensions of the cladodes. It is impossible to determine if new growth is going to be a flower or a new cladode as they are identical when first appearing -often covered with cone-shaped deciduous leaves. If a rounded pericarpel, this later becomes the fruit and may turn a bright red color or stay green. Some Opuntias have very juicy, fleshy fruit called "tunas" that are harvested and turned into candies or jellies. Similarily, cladodes when still young and tender are harvested and eaten as a vegitable - particularly in Mexico under the name Nopales.
For ornamental purposes, Opuntias are rarely grown except as a novelty or even to create a barrier on property lines. Many people despise the Opuntia, even those who otherwise love growing cacti. In recent times, however, there seems to be a renewed interest in the genus - particularly the species native to the Southwest U.S. and it is gaining in popularity. However, species from central Mexico south are still very poorly known.
It also seems that many Opuntia species hybridize easily in the wild and one population tends to blend into another. This further confounds taxonomists and therefore this genus will long frustrate those trying to separate it into a tidy division of various species.