Sorry, Ina, I just have to continue the thread... I find it amusing that I have seen more opuntias and agaves in China and South Africa than in their native North America. The opuntias in China were definitely of the invasive type, covering entire hillsides in Yunnan. I wonder how and why they were introduced. I didn't see any agaves in China, but there were plenty in South Africa. The generic Agave americanas showed up in very strange places, especially the variegated types. You could be driving down a road in the middle of nowhere, kilometers from the nearest farm, and bam! there's a variegated agave out in the bush, a hundred meters from the road. This had to have been intentionally planted. They were much more common around the older farms. Every once in a while you encounter a spot where the sisal agaves were trying to take over, however. The opuntias were frequent, but not nearly as invasive as the Chinese types. They tended to be at odd places along the road, or for some reason, near cemeteries. To make this legal, yes, there were geophytes growing near the North American natives in far off lands. I recall some nice Arisaema consanguineum mixed in with the opuntias in China, and albucas were common companions for the agaves in South Africa. So there. --Roy NW of Boston 8 inches of rain last Saturday, with a foot of water in the greenhouse, no harm done.