G32 

 BROMES 



Bro'mus spp. 



Brome is a large and very important genus, of the fescue-bluegrass 

 tribe, found mostly in the North Temperate Zone. With very few 

 exceptions the native western species are perennials, but about a 

 dozen annuals, usually known as chess, or cheat, are naturalized on 

 western ranges from the Old World. Another foreigner, the peren- 

 nial smooth brome (Bromus inermis), has proven to be one of the 

 most valuable species for reseeding certain western mountain ranges. 1 

 Bromes are robust grasses and generally make a moderately rank 

 growth. The name "brome" comes from a Greek word meaning 

 "food", and it is a fact that most species are eaten with relish by 

 livestock at certain times or even throughout the growing season. 

 A few bromes are valuable for hay. On the other hand, some of 

 the annual bromes are highly undesirable weeds because of their 

 invasion of agricultural lands. Some of these annuals have stiff 

 prominent bristles (awns) that penetrate eye, nose, and mouth tis- 

 sues, causing sores and blindness in livestock and game. Ripgut 

 grass (B. ricjidus], introduced from the Mediterranean region into 

 California and contiguous States, is, when mature, a particularly 

 serious menace because of its detached sharp-pointed florets and 

 long, hard, spinelike awns. 



Several characters help to distinguish bromes from other genera 

 in the fescue tribe to which they belong. Leaf blades are character- 

 istically flat and relatively broad with the edges of the leaf sheath 

 grown together forming a tube. The seed heads (panicles) are sel- 

 dom spikelike but usually more or less open and spreading. The 

 low^er glume, i. e., the lower of the two bracts at the base of the 

 group (spikelet) of little flowers (florets), has 1 to 3 nerves and 

 the upper, 3 to 9, usually 3 to 5. Backs of the florets are rounded 

 in most species, but in others only on the lower part, whereas toward 

 the top the midrib stands out like the keel on the bottom of a boat. 

 The rather rigid outer seed husk (lemma) is notched at the tip, 

 making two teeth between which the beard (awn) arises, and the 

 veins (nerves) of the lemma converge at the apex. 



1 Forsling, C. L., and Dayton, W. A. ARTIFICIAL RESEEDING ON WESTERN MOUNTAIN 

 RANCH LANDS. U. S. Dept. Agr. Circ. 178, 48 pp., illus. 1031. 



