This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Introduced. Annual. Propagates by seeds.
Time of bloom: Late June to July.
Seed-time: July to August.
Range: Locally in most of the United States as far south as Georgia; abundant on the Pacific Coast; occasional in Canada from New Brunswick to Manitoba; very troublesome in Red River Valley.
Habitat: Grain fields and waste places.
Darnel is now said to be poisonous only when diseased, its toxic properties being due to a fungus which has recently been discovered in the tissues under the seed coats. It is reputed to be most dangerous in wet seasons or when grown on wet soil. When ground with wheat, bread made from the flour is likely to cause "eruptions, trembling, and confusion of sight in man and flesh-eating animals"; and if the seeds are malted with barley, the ale or beer "causes intoxication very suddenly"; but the plant is said not to be harmful in any way to grazing animals, and makes excellent hay when cut before seeding. Poultry also eat the seeds without any bad effects. (Fig. 30.)
Fig. 30. - Darnel (Lolium temulentum). X 1/4.
Culms two to four feet tall, simple, erect, smooth. Sheaths overlapping, smooth; blades six inches to a foot long, about a quarter-inch wide, smooth below but somewhat rough above, deep green. Spikes four to eight inches long, the rachis flexuous and grooved on its sides, the spikelets sessile and attached to the rachis with their edges resting in the alternate curves; spikelets five to seven-flowered, the lemma sometimes awned, sometimes not; the glume at the base of each spikelet equaling or exceeding it in length, looking like a bract in the axil of which the spikelet sits. Seed slender, brown, boat-shaped, with a deep groove on the inner side, appearing somewhat like a slim, hard grain of wheat; the palea is closely adherent to it, making it about as heavy as a kernel of wheat and difficult to separate from that grain when threshed with it.
Sow clean seed. Grain containing Darnel should not be milled but should be fed to cattle or poultry; or the crop should be cut green and used as hay. Darnel-infested land should not again be used for grain until the rotation has included some cultivated crops.