I had never seen a type of cholla like the one a saw on this morning’s hike in Joshua Tree National Park. Short branches all neatly, geometrically, arranged around the main stalk. Other cholla I’ve seen are much more random in shape.
I googled when I got back within signal range and eventually learned these are called Blue Diamond cholla, or Clokey Cholla, Opuntia multigeniculata, Opuntia whipplei var. multigeniculata, Cylindropuntia whipplei var. multigeniculata. So now I know. I just need a chance to casually slip Opuntia whipplei var. multigeniculata into a conversation.