Knotroot bristlegrass

Setaria geniculata



Erect or spreading stems grow from a bent, knee-like base. The underground rootstock is short and knotty. Blades and stems often have a purplish tinge. The blades are straight, flat and not twisted. They are long and pointed at the tip, tapering toward the base. The seed head is erect, 1 to 3 inches long, 1/4 inch wide, rounded at the top, and greenish yellow or purple in color. There are five or more bristles below each egg-shaped spikelet. Yellow bristlegrass has the same general appearance except that it is an annual with twisted leaves and no rootstock knots.)

Knotroot bristlegrass is a perennial, warm-season, native - 12 to 36 inches tall.

Fair grazing for both livestock and wildlife.


Grows on open ground in cultivated soil and moist places, especially in pastures and along roadsides.