This post is about another grass I identified with the help of the book I bought at the Tall Grass Prairie Preserve in October. This one is named Windmill Grass. I first noticed this grass when I found piles of it laying around in areas sheltered from the wind, like this.
The dried seed heads had broken off and were blown around by the wind until they came to rest in the corner of one of our cold frames. Here is a closeup picture of one of these.
You can kind of see why it is called Windmill Grass. Like Prairie Threeawn, it is another of the native grasses we have here in Oklahoma.