How do I get rid of Quack gr from my lawn?

In this part of the globe we call it "Twitch" This is not a problm per sae, it is an infestation. Very difficult to get rid of. You must dig it out and burn it, any little bits left will grow again. it is very deep rooted, but if you decide to dig it out, use a garden fork rather than a spade, which will only serve to cut the roots to bits thus make the problem worse.Dig at least 1ft deep and pick up every tiny piece. .