Hello dear friend @ewkaw good afternoon
Nature is wonderful, it makes things that in addition to being beautiful serve many purposes, who would say that this grass could be edible.
Here in Corrientes Argentina I have not seen this plant, there is one very similar but its flowers are yellow
Thank you very much for sharing these beautiful photographs and all your information.
Have a beautiful weekend
It is possible that you do not have this one. But it is good to know local plants - I am sure a lot can be used in the kitchen.