This grass was abundant in a field along the Serpentine Loop trail.There is one picture with the grass highlighted against a post, then another with a piece held against my hand. The park guide to plants lists at least five species of bromus in this section of the park. Thanks for the assistance.
This seemed rather distinctive - dark red stems and interestingly-shaped overall - but I could not find it on the plant guide for the park. Whenever I find a plant that I think is interesting, it turns out to be an awful invasive that must be destroyed. I await your verdict, sister and fellow users.