@Fiat,
I believe the one you're asking about is Opuntia cylindrica cristata. I took this from Cactus Collection's website (
http://www.cactusshop.com/libr...):
"Opuntia cylindrica is native to Ecuador and Peru. Forms an arborescent, branching specimen to 12' with time. This is a cristate form, producing "fanned" growth of emerald green with white areoles and tiny spines.Cristate forms generally occur when injury occurs to the plant at a young age (this damage can be due to insects eating the growing tip, or from many other causes, including a genetic predisposition). In reaction to the "injury", the cells at the tip of the branch where growth occurs begin to multiply at a much faster rate and the normal growing tip "goes crazy", creating fantastic whorls and fans. Porous cactus soil with adequate drainage. Bright light with ample airflow. Water thoroughly when soil is dry to the touch. Protect from frost."
I can't remember the exact details, but they produce little green "leaves" at certain times of the year and the rest of the year they're gone. They also become more "fuzzy" at certain times of the year with this cobwebby looking white hair. If I remember reading correctly, they are rot prone and adequate drainage is a must.
Planto
