SETARIA LUTESCENS
21. Setaria lutescens (Weigel) Hubb. Yellow Bristlegrass, Yellow Foxtail, Pigeon Grass.
A semi-erect, fibrous-rooted annual of waste places, cultivated ground or over-grazed pastures.
Leaves rolled in the bud-shoot. Sheath much compressed, sharply keeled, glabrous, pale green or frequently tinged with purple and red towards base or on the veins, split, loose; hyaline margins sometimes overlapping. Auricles absent. Collar narrow, distinct, continuous, glabrous, pale green, purplish or reddish. Ligule a fringe of short hairs 1 mm. long or less, fused at base. Blade 4 to 10 mm. wide, 5 to 30 cm. long, flat, V-shaped towards base, keeled, soft drooping, taper-pointed, not ridged but midrib prominent, slightly scabrous, light green; upper surface slightly glaucous and bearing long, twisted and flexuous hairs near base; margins smooth or slightly scabrous.
This species is distinguished from S. viridis by the flexuous, twisted and hygroscopic hairs at the base of the blade and by the absence of cilia on the flattened sheath.