That bamboo stuff is called Japanese Knotweed. It is terribly invasive. Make sure that if you use any equipment to cut it down that NO pieces remain on the mower or whatever, because it will spread from just a small cutting. My dad used to try to kill it with herbicides, to no avail. Try vinegar. White vinegar mixed half and half with water. Dump it on well, so the roots get it too. Works for a small area, but it is difficult stuff.
