I get it along 2 fences and keep it under control by digging it up and getting most of the root out each spring, then spot spraying when I see the odd leaf with 'Round Up'. I never fully get rid of it as both my neighbours have it and do nothing to control it.

yes it is a case of being vigilant. pull as much as you can, digging the 'pip' out with it. in the late summer treat with a glycophosphate weedkiller and then that is taken down to the roots and destroys them over winter. I have had success with this method.