LOLIUM PERENNE
1. Lolium perenne L. Perennial Ryegrass, Common Darnel.
A fibrous-rooted, entirely glabrous, tufted perennial occurring almost exclusively in periodically reseeded meadows and pastures.
Leaves folded in the bud-shoot. Sheath usually compressed but sometimes almost cylindrical, not keeled, glabrous, pale green, reddish at base, closed or split. Auricles small, soft, clawlike. Collar narrow, distinct, glabrous, yellowish to whitish green. Ligule thin-membranous, 0.5 to 2 mm. long, obtuse, toothed near the apex. Blade 2 to 6 mm. wide, 5 to 15 cm. long, sharply taper-pointed, keeled, prominently ridged on upper surface, smooth and glossy on lower surface, bright green; margins slightly scabrous.
This grass closely resembles L. multiflorum and Festuca elatior, from which it is distinguished by the folded leaves in the bud-shoot.