50 



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



24. Bromus commutatus Schrad. Hairy chess. (Fig. 37.) Re- 

 sembling B. secalinus, but the sheaths retrorsely pilose; lemmas at 

 maturity less plump and more overlapping ; awn commonly somewhat 



longer. O — Introduced from Europe, 

 a weed in fields and waste places, Wash- 

 ington to California and Montana and 

 eastward through the Northern States, 

 thence less commonly southward . Bromus 

 commutatus var. apricorum Simonkai. 

 Lemmas pubescent. O — Washington to 

 California; rare. Introduced from Europe. 

 25. Bromus mollis L. Soft chess. 

 (Fig. 38.) Softly pubescent throughout; 

 culms erect, 20 to 80 cm tall; panicle 

 erect, contracted, 5 to 

 10 cm long, or, in de- 

 pauperate plants, re- 

 duced to a few 

 spikelets; glumes 

 broad, obtuse, coarse- 

 ly pilose or scabrous- 

 pubescent, the first 

 3- to 5- nerved, 4 to 6 

 mm long, the second 

 5- to 7-nerved, 7 to 8 

 mm long ; lemmas 

 broad, soft, obtuse, 

 7-nerved, coarsely 

 pilose or scabrous- 

 pubescent, rather 

 deeply bidentate, 8 

 to 9 mm long, the 

 margin and apex hy- 

 aline ; awn rather 

 stout, 6 to 9 mm long; 

 palea about three- 

 fourths as long as 

 lemma. O — Weed 

 in waste places and 

 cultivated soil, introduced from Europe, abundant on the Pacific 

 coast, occasional eastward to Nova Scotia and south to North 

 Carolina (fig. 39). This has been referred to B. hordeaceus L., a 

 distinct European species. 



26. Bromus molliformis Lloyd. (Fig. 40.) 

 Culms erect, mostly 10 to 20 cm tall, some- 

 times taller; lower sheaths felty-pubescent, 

 the upper glabrous; blades narrow, the upper 

 surface with scattered rather stiff hairs ; panicle 

 2 to 4 cm long, ovoid, dense, few-flowered; 

 spikelets oblong, compressed, 12 to 18 mm 

 long; glumes about 6 mm long, the second 

 broader, loosely pilose, the hairs spreading; lemmas thinner and 

 narrower than in B. mollis, closely imbricate, about 8 mm long, 



Figure 37.— Bromus commutatus, X 5 

 (Amer. Gr. Nat. Herb. 890, Va.) 



Bromus mollis, 

 (Hall 258, Calif.) 



Figure 39.— Distribution of 

 Bromus mollis. 



