Common name
Stiff Ryegrass
Annual Ryegrass
Rigid Rye Grass
Wimmera Ryegrass

Derivation
Lolium L., Sp. Pl. 83 (1753); Latin name for darnel (Lolium temulentum) a weed of corn fields.

loliaceum- Inflorescence resembles that of Lolium. Originally described in another genus.

Published in
Ann. K.K. Naturhist. Hofmus. 28: 32 (1914).

Common synonyms
Lolium rigidum Gaudin subsp. lepturoides (Boiss.) Sennen & Mauricio
Lolium subulatum Vis.

Habit
Annual. Culms erect or geniculately ascending or decumbent, 4–43 cm tall, 2–4-noded. Mid-culm nodes pallid. Lateral branches simple. Leaf-sheaths smooth or scaberulous. Leaf-sheath auricles absent, or present. Leaf-sheath auricles falcate. Ligule an eciliate membrane, 1–1.5 mm long, truncate or obtuse. Leaf-blades 5–17 cm long, 0.5–5 mm wide. Leaf-blade surface smooth or scaberulous. Leaf-blade margins smooth or scaberulous. Leaf-blade apex acute to attenuate.

Inflorescence
Inflorescence solid, a spike. Peduncle smooth or scaberulous above. Spike straight or arcuate, bilateral, 3–30 cm long, bearing 2–21 fertile spikelets. Rhachis tough, subcylindrical and excavated, (1–)1.7–2.6 mm wide, smooth or scabrous on surface. Spikelet packing adaxial, approximate, regular, 2-rowed.

Spikelets
Spikelets sunken or appressed, solitary. Fertile spikelets many flowered, comprising 2–8 fertile florets, with diminished florets at the apex, oblong, laterally compressed, 5–18 mm long, 1–3 mm wide, breaking up at maturity. Spikelets disarticulating below each fertile floret. Rhachilla internodes 0.9–2.8 mm long (25–50% of length of lemma).

Glumes
Glume 1 (the lower absent or obscure), persistent, similar to fertile lemma in texture. Upper glume lanceolate or oblong, 4–20 mm long, 75–100% of length of spikelet, coriaceous, 3–7-nerved. Upper glume surface smooth or asperulous. Upper glume apex obtuse or acute.

Florets
Fertile lemma lanceolate, dorsally compressed, 3.2–8.5 mm long, membranous or coriaceous, 3–5-nerved. Lemma surface smooth or scaberulous. Lemma apex entire or erose, obtuse or acute, muticous or rarely 1-awned. Median (principal) awn subapical, 0–3(–10) mm long overall. Palea membranous. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped. Lodicules 2, lanceolate, 0.8–1 mm long, membranous. Anthers 3, 1.2–3.1 mm long. Ovary glabrous. Grain with adherent pericarp, fusiform or ellipsoid, 2.7–5.5 mm long. Hilum linear.

Continental Distribution:
Europe, Africa, Temperate Asia, Tropical Asia, Australasia, South America, Antarctica.

Australian Distribution:
Western Australia: Carnarvon, Irwin, Drummond, Dale, Menzies, Eyre. South Australia: Nullabor, Flinders Ranges, Eyre Peninsula, Northern Lofty, Murray, Yorke Peninsula, Southern Lofty, Kangaroo Island, South-eastern. New South Wales: North Coast, Central Coast, Central-Western Slopes, South-Western Slopes, North-Western Plains, South-Western Plains. Victoria: Wimmera, Wannon, Riverina, Midlands, Victorian Volcanic Plain, Otway Plain, Gippsland Plains, East Gippsland. Tasmania: Furneaux Group, East Coast.

Classification. (GPWG 2001):
Pooideae

Notes
Introduced. Native to the Mediterranean. Roadsides, waste places, sandy areas, often in maritime habitats. Flowers Sept.–Feb. Fruits Nov.–Dec.