The desert prickly-pear, known to botanists as Opuntia phaeacantha, is the Southwest's most widespread and abundant species of cactus. Unlike the giant saguaro (Carnegiea gigantea) that is restricted ...

During his brief visit to Namibia in 2010 world expert on the control of invasive cacti Helmuth Zimmermann from Pretoria noted 23 invasive cactus species, the most dangerous of which are listed below.

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