MANUAL OF THE GRASSES OF THE UNITED STATES 



137 



11. BRIZA L. Quaking grass 



Spikelets several-flowered, broad, often cordate, the florets crowded 

 and spreading horizontally, the rachilla disarticulating above the 

 glumes and between the florets; glumes about equal, broad, papery- 

 chartaceous, with scarious margins; lemmas papery, broad, with scari- 

 ous spreading margins, cordate at base, several-nerved, 

 the nerves often obscure, the apex in our species obtuse 

 or acutish; palea much shorter than the lemma. Low 

 annuals or perennials, with erect culms, flat blades, 

 and usually open, showy panicles, the pedicels in our 

 species capillary, allowing the spikelets to vibrate in 

 the wind. Standard species, Briza media. Name from 

 Greek, Briza, a kind of grain, from brizein, to nod. 



The three species found in this 

 country are introduced from 

 Europe. They are of no impor- 

 tance agriculturally except inso- 

 far as B. minor occasionally forms 

 an appreciable part of the spring 

 forage in some parts of Califor- 

 nia. B. maxima is sometimes 



cultivated for ornament, because of the large showy 

 spikelets. 



m A 



Figure 263.— Distribution of 

 Poa juncifolia. 



B. 



MAXIMA. 



Figure 262.— Poa 

 juncifolia. Pan- 

 icle, X 1: floret, 

 X 10. (Type.) 



Panicle drooping; spikelets 10 mm wide 1. 



Panicle erect; spikelets 4 to 5 mm wide. 



Plants perennial; upper ligule 1 mm long; spikelets about 5 



mm long 3. B. media. 



Plants annual; upper ligule 5 mm or more long; spikelets 

 about 3 mm long 2. B. minor. 



1. Briza maxima L. Big 



QUAKING GRASS. (Fig. 266, B.) 



Annual; culms erect or decum- 

 bent at base, 30 to 60 cm tall; 

 panicle drooping, few-flowered; 

 spikelets ovate, 12 mm long or 

 more, 10 mm broad, the pedi- 

 cels slender, drooping; glumes 

 and lemmas usually purple or brown margined. 

 © — Sometimes cultivated for ornament; 



sparingly escaped in 

 California (Monterey 

 County). 



2. Briza minor L. 

 Little quaking grass. 

 (Fig. 266, A.) Annual; 

 culms erect, 10 to 40 

 cm tall; ligule of the 

 upper leaf 5 mm long 

 or more, acute; blades 2 to 10 mm wide; panicle 5 to 12 cm long, the 

 branches stiffly ascending, the spikelets pendent, triangular-ovate, 

 3- to 6-flowered, about 3 mm long, o — Introduced at several 



Figure 265.— Distribution of 

 Poa ampla. 



Figure 264. — Poa ampla. Pani- 

 cle, X 1; floret, X 10. (Cran- 

 dall 205, Colo.) 



