520 



MISC. PUBLICATION 200, TJ. S. DEPT. OF AGRICULTURE 



awns slender, about equaling the tip of fertile lemma; one or two 

 additional rudiments, broad and awnless, sometimes developed. 

 01 (B. oligostachya Torr.)— Plains, Wisconsin to Manitoba and 



Alberta, south to Missouri, 

 .. .tfttUStlkk Texas, and southern Cali- 



AifflP fornia; Mexico; introduced 



in a few places in the Eastern 

 States (fig. 1099). 



BOUTELOUA GRACILIS Var. 



strict a (Vasey) Hitchc. 

 Spikes 4 to 6, usually ascend- 

 ing or appressed. % 

 Rare, Texas and Arizona. 



Figure 1097.— Distribution of 

 Bouteloua hirsuta. 



15. Bouteloua breviseta 



Vasey. (Fig. 1100.) Per- 

 ennial, wiry, the base peren- 

 nial, woody, loosely tufted; 

 culms branching, 25 to 40 cm 

 tall; blades 3 to 6 cm long, 

 1 to 1.5 mm wide, flat or 

 becoming involute, sharp- 

 pointed; spikes mostly 2, 

 sometimes 1, rarely 3, 2 to 

 3 cm long; spikelets 30 to 



Figure 1098.— Bouteloua gracilis. Plant, X l A; glumes and florets, X 5. 

 (Amer. Gr. Nat. Herb. 384.) 



45, about 4 mm long; fertile lemma pubes- 

 cent, with 3 awns and acuminate intermediate lobes; rudiment 

 densely bearded at summit of rachilla joint, cleft nearly to the base, 

 the rounded lobes obscured in the dense hairs. % (B. ramosa 



