This thread may be of help to you: The thread "Bind weed"
in Irises forum
I have it in a few spots and just pull it when I notice it. It comes out easily and I don't have it spreading out all over like some folks experience. I don't mind it in my azalea, as it provides a 2nd bloom for the shrub. I do pull it when it starts to blanket the azalea, but I don't have a strong aversion to this plant that others do. Good luck.