IMPORTANT RANGE PLANTS. 27 



of water. The spikes are somewhat compressed, slender, 2 to 4 

 inches long. The spikelets are flattened, and as shown in Plate XXI, 

 are long, narrow, erect or spreading, 3 to 6 flowered, 4 to 12 in 

 number. The glumes (empty lowermost two scales) are sharp- 

 pointed but awnless; lemmas (upper flowering scales) are usually 

 provided with stout, somewhat twisted awns y 2 to 1 inch long. 



The distribution and abundance of this grass are unusual. It 

 constitutes the controlling type of plant growth below the yellow- 

 pine zone, where it is depended upon to furnish the major portion of 

 the fall, winter, and spring forage. In a few localities in Montana 

 and Wyoming it grows so dense that it is of value for hay. It extends 

 even into the Hudsonian zone (usually in scattered stand, 'though in 

 favorable situations nearly covering the ground with a rank growth) , 

 and even in this grazing type produces considerable herbage. This 

 wide distribution is due to its remarkable capacity to endure drought. 

 It is able to exist though for several days in a wilted condition, in 

 the basaltic-soil type of the higher ranges when there is but 5.5 to 

 7.5 per cent water. This accounts for the prevalence of big bunch 

 grass on scablands, benchlands, and gritty, poorly disintegrated soils 

 of low water content. 



Flower stalks first show about August 1, appearing very irregularly 

 until perhaps September 1. Both the beginning and completion of 

 production are thus unusually late, and the delay in the appearance 

 of the flower stalks is reflected both in the time of seed maturity and 

 in the fertility of the seed. Fully ripened seeds are rarely found 

 before August 20. The seed crop continues to ripen irregularly as 

 long as the weather permits, but the bulk of the seeds do not reach 

 maturity. The seed that does mature germinates rather poorly. 

 The average for 1907, 1908, and 1909 was 16, 30. and 26.5, respec- 

 tively. On the lower ranges, however, seed is matured early and 

 evenly, and a germination of 80 + per cent is often obtained. 



The large amount of herbage afforded by big bunch grass on the 

 lower ranges, and even in the upland grazing areas, places it well 

 toward the top of the list of important forage plants. No other 

 grass or forage plant is so abundant on the lower areas, nor supplies 

 so much feed. As a fall, spring, and winter feed it is preeminent. 

 When the fall rains come on, usually in September, big bunch grass 

 is awakened to growth, and for two months or more, depending upon 

 the altitude and physiography, continues its activities. This tender 

 and succulent herbage is ravenously consumed by all classes of 

 stock in the fall as well as during the winter and spring. About the 

 middle of June on the lower areas, however, the foliage becomes 

 somewhat tough and unpalatable and ceases to be of high value for 

 forage. On the higher ranges, owing to the delay in the growing 

 period and the absence of growth in the fall, the plant is grazed 



