Most of my lawn is fescue but I believe an invasive species of warm weather grass is taking over a portion of it. Can anyone help me identify what it is and how to get rid of it. Also, I'm getting ready to do my fall overseeding next month, what are the implications of treating the weed and overseeding (i.e. will my overseeding work if I'm spraying a bunch of weed killer at the same time)?

The trouble grass is brighter green than my fescue, grows in small clumps, has stolons/rhizomes, and in addition to normal blades of grass has a tall stalk of grass that gets 12"-16" over a weeks period.