Newcomers to deserts might think barrel or fish hook cactus are the worst due to their vicious, spiky needles. Nope. Cholla are. Their thin needles and pods will attach themselves to anything that brushes them. One species is called the Jumping Cholla because you swear you didn’t get near it yet there it is embedded in you.
My father-in-law once plucked Jumping Cholla needles out of me with tweezers and marveled that even though the needles were wispy they still stuck themselves half an inch deep in me.
However, they make perfect nesting areas for small birds. No predator can get near a bird nest deep in a cholla.
The “jumping cholla” name comes from the ease with which the stems detach when brushed, giving the impression that the stem jumped. Often the merest touch will leave a person with bits of cactus hanging on their clothes to be discovered later when either sitting or leaning on them. The ground around a mature plant will often be covered with dead stems, and young plants are started from stems that have fallen from the adult. They attach themselves to desert animals and are dispersed for short distances.