242 MISC. PUBLICATION 200, U. S. DEFT. OF AGRICULTURE 



FIGURE 472. Agropyron saxicola, 

 XL (Type.) 



PYRON PARISHII var. LAEVE Scribn. and Smith. Nodes glabrous; awns 

 usually 1 to 2 cm long. 91 California (Trinity County to San Diego 

 County). 



22. Agropyron saxicola (Scribn. and Smith) Piper. (Fig. 472.) 

 Culms tufted, erect, 30 to 80 cm tall; sheaths glabrous or sometimes 



pubescent; blades flat to loosely involute, 

 glabrous or sometimes pubescent, 1 to 4 

 mm wide; spike 5 to 12 cm long, the rachis 

 tardily disarticulating, the internodes more 

 or less scabrous on the angles, 5 to 10 mm 

 long; spikelets imbricate, sometimes in 

 pairs, about twice as long as the internodes 

 of the rachis, 4- to 6-flowered, the rachilla 

 minutely scabrous; glumes narrow, 2- 

 nerved, the nerves sometimes obscure, 

 sometimes with a third faint nerve, awned, 

 the awn divergent, 5 to 20 mm long, some- 

 times with a tooth or short awn at the base 

 of the main awn; lemmas about 8 mm 

 long, the awn divergent, mostly 2 to 5 cm 

 long, sometimes with 1 or 2 short addi- 

 tional awns; palea about as long as the 

 lemma, obtuse or truncate. 91 Dry or 

 rocky slopes and plains, western South 

 Dakota to Washington, south to Utah, Ari- 

 zona, and California (fig. 473). This species is a transition to Sitanion. 



23. Agropyron saundersii (Vasey) Hitchc. (Fig. 474.) Culms 

 erect, 60 to 100 cm tall; blades flat or loosely invo- 

 lute; spike erect, 8 to 15 cm long, mostly purplish, 



the rachis tardily disarticulating; spikelets some- 

 times in pairs near the middle of the spike, 1 to 1.5 

 cm long (excluding awns), 2- 

 to 5-flowered ; glumes variable, 

 narrow with 2 nerves or wider 

 with 3 to 5 nerves, the nerves 

 strong and at least the mid- 

 nerve scabrous, the awn 2 to 

 4 cm long, sometimes with a 

 short lateral awn near the 

 base; lemmas scabrous, the 



awn straight, 2 to 5 cm long. 91 (Elymus saun- 

 dersii Vasey.) Dry slopes, Colorado (Veta Pass) and 

 Utah (Salt Lake City). 



40. TRITICUM L. 



Spikelets 2- to 5-flowered, solitary, placed flat- 

 wise at each joint of a continuous or articulate rachis, FlGURE ' 

 the rachilla disarticulating above the glumes and pyron saunersu, x 

 between the florets or continuous; glumes rigid, L (Type-) 

 keeled, 3- to several-nerved, the apex abruptly mucronate or toothed 

 or with one to several awns; lemmas broad, keeled, very asymmetric, 

 many-nerved, abruptly pointed or awned. Low or rather tall an- 

 nuals, with flat blades and thick spikes. Standard species, Triticum 

 aestivum. Triticum, the old Latin name for wheat. 



FIGURE 473. Distribution of 

 Agropyron saxicola. 



