BigBluestem

=Big Bluestem= ( Andropogon gerardii)

In this picture you can see the characteristic 3-pronged, purple top to the grass - indicating it is Big Bluestem (USDA site).
__Links:__ USDA site http://plants.usda.gov/java/profile?symbol=ANGE

Wikipedia entry http://en.wikipedia.org/wiki/Big_bluestem

Talks about two different varieties of the species that occur in two different habitats: http://www.fs.fed.us/database/feis/plants/graminoid/andgerg/all.html