IMPORTANT RANGE PLANTS. 7 



Mountain bunch grass (Plate III) forms densely tufted hummocks 

 or bunches. It has coarse, deep, and spreading perennial roots; 

 erect, slender, and smooth culms from 1 to 2 feet high, slightly 

 thickened at the base; a preponderance of rather long inwardly rolled 

 (involute), smooth or somewhat rough basal leaves; and open semi- 

 nodding panicles, composed of rather compressed spikelets, often of 

 a dark purple color, bearing 3 to 6 florets. 



As indicated by its usual habitat, mountain bunch grass stands 

 near the head of the list in drought-resistant qualities. Well estab- 

 lished plants subjected to the gradual drying process began wilting 

 excessively when the water content was reduced to 9.5 per cent, and 

 did not, as a rule, recover after the per cent of water dropped to 

 7. Such a low amount of water about the main roots would be 

 very unusual, of course, on the high range, but it shows the possi- 

 bilities of mountain bunch grass in dry situations. 



Observations during 1907, 1908, and 1909 showed that the flower 

 stalks were sent up from July 5 to August 20, July 10 to August 25, 

 and July 3 to August 15 in the respective years. The seed crop for 

 these seasons began to ripen as early as August 5, and by September 

 5 practically the entire crop had matured. The seeds are dissemi- 

 nated almost immediately upon reaching maturity. Flower-stalk 

 production and seed maturity occur earlier upon coarser, less de- 

 composed soils, where the soil water is readily reduced through evap- 

 oration and where the temperature in the substratum is relatively 

 high. 



Mountain bunch grass seed has a low viability. The average for 

 all laboratory tests made during the three seasons was 12.2 per cent. 

 Field tests in the natural habitat, with seed from the same source, 

 gave a much higher percentage of germination. 



Upon the higher ranges mountain bunch grass is grazed ravenously 

 by all classes of stock. It is most highly relished at the time of 

 flower-stalk production, the entire aerial portion, including the succu- 

 lent leaves and the flower stalks, often being removed at that time 

 by a single grazing. As the season advances, sheep discriminate be- 

 tween the leaf blades and culms, and when the plant has matured its 

 seeds the latter are rarely cropped. Ripening of the seed crop, how- 

 ever, impairs the plant's palatability and nutritiousness but little. 

 As a rule, the leaf blades are not eaten so closely as earlier in the 

 season, and the fibrous stems or seed stalks remain untouched. But 

 little else of the forage is wasted. 



The nutritive value of mountain bunch grass is indicated in Table 1, 

 which also presents an analysis of well cured timothy hay for com- 

 parison. 



