I have the invasive grass/weed shown in the picture in many places in
my lawn. The spots of weeds pop up with no apparent source. They do
no respond to weed killer, and they crowd out regular lawn grass. I
am in the Chicago suburbs. Can anyone tell me what the grayish green
grass/weed is and how to get rid of it?

http://www.flickr.com/photos/bobhofmann/4761771580/

Thanks,

Bob Hofmann