This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Native. Perennial. Propagates by seed.
Time of bloom: June to July.
Seed-time: July to August.
Range: Plains of the Missouri River, the Rocky Mountain foothills of Northwest Canada, and in New Mexico and California. Habitat: Dry soil; wild meadows and pastures.
A close relative of the preceding species but not quite so vicious. Both these grasses make excellent forage when young, and good hay when cut before seed development; but there are grasses, as good as these or better, that do not carry such offensive weapons.
Culms erect, smooth, simple, one to two feet tall, growing in thick tufts or mats. Sheaths overlapping, mostly crowded at the base, the upper ones long and loose and often enclosing the lower part of the panicle; basal blades about half as long as the culm, involute, with very long, thread-like tip; stem leaves three to six inches long, broader than the basal ones, involute. Panicle erect, six to ten inches long, somewhat loose and spreading; spikelets one-seeded, the glumes exceedingly narrow and tipped with long bristles, the lemma with an acute callus; awn four to eight inches long, rough-hairy and twisted in the lower part, extremely slender, flexible, and thread-like; not harmful when caught in the coats of animals but very objectionable in hay.
Means of control the same as for the preceding species
 
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