Well, I'm no university plant taxonomist, but that's no June Grass, either! Unless this "scientist" was using June Grass as a common name for something besides Koeleria sp. Did the person give you a Latin name? Just out of curiousity, I googled June grass, and apparently in Europe it is used to refer to Kentucky bluegrass, etc, in our lawns, which it also obviously isn't!

Compare it to Barnyard Grass, and see where you get with that.

dbs_illinois,

Thank you. It almost certainly is Barnyard Grass. I love it for its long, broad, dark, and shiny blades. It showed up in my native plant garden as an accidental. I will not let it become invasive, but I'll be glad for it to take over a small area.

If I my research is correct, it is not a native of either Illinois, Texas, nor the USA.

I have lots of Koeleria macarantha and looks nothing like that.