A native perennial bunchgrass known for its showy, reddish-purple seed heads that appear in late summer, often called "grease grass" because of an oily film on its spikelets. 
 
PURPLETOP TRIDENS “Tridens flavus (L.) Hitchc.”
Scientific Name: Tridens flavus.
Height: Grows 2 to 6 feet tall.
Inflorescence (Seed Head): A large, open, pyramid-shaped panicle with drooping branches, displaying purplish spikelets.
Unique Trait: An oily coating on the spikelets gives it the nickname "Grease Grass".
Habitat: Found in savannas, fields, woodland edges, and along roadsides.
Ligule: A distinctive fringe of short, stiff hairs at the collar where the leaf blade meets the sheath.