I'm not aware that this shrub does that, Guest.

It will send up shoots from underground, but normally very close to the mother plant. A few of the dwarf kinds, such as 'Harbor Dwarf', can spread more widely. All spread more quickly in sandy soil.

I don't disbelieve you, Tug - but mine certainly doesn't do this. Probably the 'wrong' soil! lol.

Maybe the long, hot summers encourage it to roam around, Spritzhenry. "There's got to be someplace cooler around here somewhere!!" : D

LOL, Tug - we didn't get a summer last year, and come to think of it, not the year before, either - just a few warm days here and there. It could well have an effect on the plants!