Annuals or perennials. Leaf-blades flat or rolled, often auriculate. Inflorescence a stiff 2-sided spike, the spikelets alternate in opposite rows with one edge sunk in hollows in the continuous axis. Spikelets 3-12(-22)-flowered, the uppermost floret reduced, the lower (adaxial) glume suppressed in all except the terminal spikelet and there similar to the upper; upper glume persistent, external, linear to oblong, 5-9-nerved, becoming hardened; lemmas rounded on the back, 5-9-nerved, awnless or with a straight awn from near the tip; palea as long or nearly as long as the lemma.

A genus of 8-12 species in temperate Europe and Asia; widely introduced elsewhere; 5 species occur in Pakistan.

The taxonomy of the genus is confused by the relative ease with which the species will hybridise and introgress. Some of the species will also hybridise freely with certain species of Festuca (none of these hybrids, x Festulolium spp, have been reported from Pakistan to date), and this has sometimes been considered an indication that the two genera should be united. Variation within individual species is such that no key can be constructed that will place every specimen correctly, and indeed some plants are bound to remain of uncertain affinity (particularly if the specimens are incomplete or immature). Lolium rigidum Gaud. var. duthiei Hack. ex Hook.f., Fl. Brit. Ind. 7:364. 1896 is such a plant. Terrell (l.c.) states that at present it is impossible to tell whether it is a form of Lolium rigidum or Lolium temulentum, since it has the rigid spike of the former but the awned lemmas of the latter.

Lower Taxa

• Lolium multiflorum Lam.
• Lolium perenne Linn.
• Lolium persicum Boiss. & Hohen. ex Boiss.
• Lolium rigidum Gaud.
• Lolium temulentum Linn.