Johnsongrass Sorghum halepense (L.) Pers.
Bright green leaves are hairless with a prominent, white midvein. Leaves are rolled in the bud and may be up to 24 inches long. Leaf sheaths are also hairless.
Very prominent, jagged, membranous ligule.
Erect, stout, hairless stems may reach 10 feet in height. Round to sometimes flattened stems are purple-tinted at the base. Plants form dense patches by purplish, thick, scaly rhizomes.
Flowers and fruit
The seedhead is a purple, very large, open and spreading, pyramid-shaped panicle that consists of numerous whorled branches. Seeds are oval, shiny and reddish brown.