opuntia

Any plant of the genus Opuntia, the largest genus of the cactus family. Native to the New World, it has characteristic small bristles with backward-facing barbs. Subgroups are based on the form of the stem segments: chollas have cylindrical joints, while prickly pears have flat joints. Sizes range from tiny, cold-hardy forms to treelike varieties. In the Northern Hemisphere, opuntia is found farther north than any other cactus.

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