Knotroot Bristlegrass

Knotroot Bristlegrass, Yellow Bristlegrass, Marsh Bristlegrass

Setaria parviflora (Poir.) Kergu�len

Poaceae (Grass Family)

mature plants ▲ ▼

▲ ▼ mature plants

stem bases ▲

inflorescences ▲ ▼

▲ emerging inflorescence

close up of inflorescence ▲

▲ ▼ ligule and collar region

▲ short, knot-like rhizomes

Knotroot Bristlegrass, Yellow Bristlegrass:

Warm-season creeping perennial grass in the same genus as the annual foxtails (Setaria)
Grows 12-36" tall and produces rhizomes that have knotted appearance (hence name)
Similar in appearance to yellow foxtail, with stiff, upright, yellowish to reddish-yellow inflorescences on upright stems
Leaf blades often more blue-green than yellow foxtail, and can be flat or with a fold at the midvein (younger leaves)
Have few or no hairs at the base of the leaf blades (yellow foxtail has long white hairs at base of leaf blade)
Stem bases/sheaths may be purplish or reddish