Opuntia other locations. Prickly pears (mostly "Opuntia stricta") were originally imported into Europe during the 1500s and Australia in the 18th century for gardens, and were later used as a natural agricultural fencing and in an attempt to establish a cochineal dye industry. They quickly became a widespread invasive weed, eventually converting of farming land into an impenetrable green jungle of prickly pear, in places high. Scores of farmers were driven off their land by what they called the "green hell"; their abandoned homes were crushed under the cactus growth, which advanced at a rate of per year. In 1919, the
Opuntia fragilis in). Both the common and scientific names refer to the easily detached stem segments. This is known to be a means of plant dispersal. "Opuntia fragilis" is a small, prostrate plant, rarely more than 4 inches high: joints tumid, fragile, easily detached, oval, elliptical, or subglobose, 1-2 in. long and nearly as thick as broad, bright green: areoles ¼-½ in. apart, with whitish wool and a few white to yellow bristles, which are much longer and more abundant on older joints; spines 1-4, occasionally a few small additional ones, weak, dark brown, the upper one usually longer and stronger than