Schizachyrium scoparium var. scoparium  
Family: Poaceae
broom beard grass, broom blue-stem, little blue-stem
[Andropogon neomexicanus Nash, Andropogon praematurus Fernald, Andropogon scoparius var. frequens Michx., Andropogon scoparius var. neomexicanus Michx., Andropogon scoparius var. polycladus Michx., Andropogon scoparius var. septentrionalis Michx., Andropogon scoparius var. villosissimus Michx., Schizachyrium praematurum (Fernald) C.F.Reed, Schizachyrium scoparium subsp. scoparium (Michx.) Nash, Schizachyrium scoparium var. frequens (Michx.) Nash, Schizachyrium scoparium var. neomexicanum (Michx.) Nash, Schizachyrium scoparium var. polycladum (Michx.) Nash]
Schizachyrium scoparium var. scoparium image
from USDA Plants website  
Schizachyrium scoparium var. scoparium image
Schizachyrium scoparium var. scoparium image
Schizachyrium scoparium var. scoparium image
Schizachyrium scoparium var. scoparium image