Jean, I think your plant is Japanese knotweed but the name is now Fallopia.  I have the variagated one which does not seem to out grow the space, especially in the shade.

Nancy

Don....I'll post pix of the bamboo when Chris gives the all-clear. It's the only bamboo I've been brave enough to try as keeping the sumac and macleaya in check have left me wary of this sort.