is found in a broad band along the coast of southern California, up to 50 miles inland, territory it shares with opuntia oricola
and opuntia ficus-indica
. This cactus forms large clumps, many feet across, rather untidy in appearance, and it blooms in late spring, producing large flowers colored various shades between yellow and dull red.
The ovate pads are up to 12 inches long and 5 inches across, crossed by neat rows of areoles (up to seven per row), bearing between four and 11 spines, white to pale yellow, often reddish brown near the base. The longest spines are around 1.5 inches, and angled outwards; shorter spines are reflexed. Fruits are reddish purple, with up to 36 areoles, some bearing a few short, bristle-like spines.