Grain? Grass? Both?

I know these photos make it rather difficult to tell what this is. It's growing in a clump close to the clump of wheat that's growing in my garden. I checked my "Weeds of Eastern Washington" but it's not one of the grass family, at least not in there. (Added Note: I forgot that you can get a better/enlarged view by clicking on the photos...duh)

It's started falling off when bumped into, so I cut the ends off to check for seeds. They are TINY! And difficult to removed from the hull. Also rather flat, but not very dark. Absolutely know clue. Anyone else?