Setaria viridis var. viridis  
Family: Poaceae
green bristle grass, green foxtail
[Chaetochloa viridis (L.) Scribn., Panicum viride L., Setaria viridis var. breviseta (L.) P.Beauv., Setaria viridis var. robustaalba (L.) P.Beauv., Setaria viridis var. weinmannii (L.) P.Beauv.]
Setaria viridis var. viridis image
from USDA Plants website  
Etymology: Setaria: from seta for "bristle"
Plants: annual grass
Conservation Status: Introduced - naturalized
Setaria viridis var. viridis image
from USDA Plants website  
Setaria viridis var. viridis image
Botanical Illustration  
Setaria viridis var. viridis image
Setaria viridis var. viridis image