I have Acre growing in many places in my garden. It turns up in the strangest spots. Not sure how it does it unless bits and pieces get kicked out of place and then start growing where ever it lands. It is trying to take over my 2' garden path in spots but as you say it is easy to remove. Grows fast though. I have one little path with large stones in it and the sedum is growing around the stones. I trimmed it back some to be sure the entire stone was available for stepping on. The poor sedum just gets squashed if walked upon. Has pretty little yellow flowers even.
