Twitch grass is also known as Couch Grass, and Quack Grass, and a number of other names some of which I can't use here. The most effective means of control I have found is to work at pulling up all of the rhizome the plants send out since those rhizomes will produce a new plant about every 6 inches which then grows into a clump of grass.
There are some that will suggest using one of the glyphosate products which I have not found to be worth the cost.