40 GRAMINEAE (GRASS FAMILY) 



for half its length, usually with a double bend beyond the straight 

 spiral. (Fig. 15.) This spiral awn relaxes when damp and 

 tightens again when dry, enabling the seed to bore its way 

 into the soil with the sharp beak at its base ; but if caught in 

 the wool of a sheep it bores just as readily into the flesh of the 

 animal, the stiff hairs near the base of the seed holding it in place 

 while the awn twists and untwists through days of torment, 

 making sores which injure the quality of the wool and some- 

 times endanger the creature's life. Hay containing the awns is 

 worse than worthless, for, when eaten by horses, cattle, or sheep, 

 the broken bits lodge in the intestines, causing inflammation so 

 serious as sometimes to end in death. 



Means of control 



Mowing so frequently or grazing so closely as entirely to prevent 

 the formation of seed. If the grass is very abundant, the land 

 should be broken up and put to a soiling crop before reseeding. 



WESTERN STIPA 

 Stlpa comata, Trin. & Rupr. 



Other English names: Needle-grass, Needle-and-thread. 



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 



