Identify Weed/Grass

 Last fall I took my yard down to bare ground, re-seeded and strawed it.
I guess the straw had some weed/grass seed in it.

I have a good stand of  fescue but it's now being taken over by this stuff.
(see picture at "Identify Weed/Grass" in alt.binaries.pictures.gardens)

I live in Southern Illinois close to St. Louis, MO.

Can anyone tell me what this is and how to get rid of it.