Opuntiads of the USA

Mission

Opuntia Species

Assorted Cacti

Opuntia Country One
Opuntia Country Two
Opuntia CountryThree
Opuntia Country Four
Opuntia Country Five

Opuntia Country with
Daiv Freeman

World Opuntiads

Notes from the Editors

Culture Notes

Literature

Editorial Board

News

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Agave Photos

Opuntia species occur from Canada to southern Argentina and Chile, and are one of the most successful cactus groups in terms of biomass, habitats conquered, and geographic distribution. Their flowers are often large and colorful, and their fruits and cladodes are consumed by animals and people in many countries.

Opuntia are characterized by their unusual stems; the platyopuntias are generally called “beaver tail” types of opuntiads. Platyopuntias have flattened stems called cladodes, which are protected by spines and glochids. The cladodes (beaver tail pads, or "pads") function as photosynthetic organs; the pads are not leaves. Like most stems, cladodes have shoots and leaves and can bear branches and flowers. Opuntia leaves are small and short-lived, typically falling off when the shoot is young; such leaves may be just an eighth of an inch long and not noticed by the casual observer because their time on the plant is short. Alternately, some species of Opuntia (or opuntiads) may have leaves 2 or 3 inches long that can last many months on the plant.

Cylindropuntias also have modified stems that serve as photosynthetic organs, but these are not flattened and the plants do not have beaver tail-type pads. For instance, C. imbricata is a large opuntiad that can reach 5 to 8 foot-tall, and its cylindrical stems look nothing like an Opuntia with pad-type stem joints.

In the wrong place Opuntia can be destructive weeds; they can overrun cattle grazing lands and they have become introduced into other continents where they have been serious pests. In addition to ruining grazing areas, Opuntia may also out compete certain native plants and thereby upset ecosystems. Opuntia have some of the nastiest spines (including glochids) found in cacti. Glochids are tiny spines that may appear hair like; they are smaller than typical spines and are hair-like; glochids are "little spines” produced in areoles along with "regular" spines. An unfriendly encounter with an Opuntia can leave a lasting bad memory.

The emphasis herein is on plants that have the beaver-tail look; these are the prickly pear cacti with the broad and flat cladodes. However, other opuntiads are described as well because they are interesting, or used to be treated as members of the genus Opuntia.

Opuntia dillenii