1. Austrocylindropuntia subulata. 2. Despite being a high-altitude species it is a bit sensitive to cold, the leaves can fall off at "fridge temperatures", and they are said not to be frost-hardy (I have not tried myself). 3. Yes, they like sun. 4. Depends so much on heat, humidity etc. As many opuntioids they want more water in summer than most other cacti. If the leaves shrivel it is time to water. 5. Easy (for a cactus). 6. Don't know, probably several decades. 7. No, because it looks like it has been grown from a cutting. 8. Cuttings! 9+10. Yes, they offset, both at the base and higher up. 11+12 (what is the difference between maturity and flowering size?). It is not as much the age as the size. I'm not sure of exactly how big they need to be. They do flower in cultivation, but they don't come as easily as on many other opuntioids. Oh yes. In nature up to 4 meters. With time, yes.

marilyn_sue... my neighbor had a very pretty one that belonged to her MIL. She never used it, then someone suggested to her she should take it to a florist and have an arrangement made for it. She did, pulling the colors from the tureen, and she now puts it on display on her sideboard. It is just beautiful there & such a great idea! Of course it could still get broken, but chances are not as great as actually using it. (ask me how I know that!lol)

Those mine tunnels are very mysterious looking. Where does the cold air come from?

Hahahahaha! When my DGD was 3 & DS was "watching" the 4 kids (oldest was 5, twins were about 18 mos.) she had a TP "incident" & the way my DS described it, there was a few inches of overflowed toilet water on the bathroom floor & little Zac "was floating on his back in it." When my brother was about 3, he threw a potato in the toilet. 40+ yrs. later I can still see my Mom trying to get it unstuck from the drain hole with a fork!