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



panicles smaller, compact, the branches of the terminal panicle as 

 much as 2 cm long, about equally distributed; bristles single below 

 each spikelet, 1.5 to 3 cm long; spikelets 3 mm long. OJ. Open 

 ground, mostly on coral rock or coral sand, Florida; Bahamas. 



5. Setaria villosissima (Scribn. and Merr.) Schum. (Fig. 1569.) 

 Perennial, as much as 1 m tall ; blades flat, villous or scabrous only, 

 15 to 30 cm long, 5 to 10 mm wide; panicle rather loose, more or less 

 interrupted, tapering above, as much as 25 cm long, the branches 



ascending, the axis vil- 

 lous; bristles 1.5 to 2.5 

 cm long ; spikelets about 

 3 mm long, the second 

 glume slightly shorter; 

 fruit finely rugose. Oj. 

 A rare or little-known 

 species from a few local- 

 ities in Texas, and possi- 

 bly from Arizona. Differing 

 from S. macrosperma in the vil- 

 lous blades and looser panicles. 

 6. Setaria macrostachya 

 H. B. K. PLAINS BRISTLEGRASS. 



(Curtiss 3617, Fla. 



pen 



FIGURE 1567. Distribution of 

 Setaria verticillata. 



(Fig. 1570.) Perennial, densely 

 tufted, usually pale or glaucous, 

 40 to 120 cm tall ; blades flat or 

 folded, scabrous on the upper 

 surface, rarely pubescent on both surfaces, 15 to 40 cm long, 3 to 

 10 mm wide; panicle spikelike, 10 to 25 cm long, mostly 5 to 10 mm 

 thick, somewhat tapering but not attenuate, more or less interrupted 

 or lobed; bristles 10 to 15 mm long; spikelets 2 to 2.5 mm long, 

 very turgid; fruit rugose. 91 Open dry ground and dry woods, 

 Texas to ^ Colorado and Arizona; Mexico (fig. 1571). Variable, 

 especially in the thickness of the panicle, sometimes very slender, 

 occasionally to 15 mm thick. The type, from Mexico, is the robust 

 form with thick panicles. 



Setaria setosa (Swartz) Beauv. Panicle interrupted, attenuate at 

 apex. Ot Ballast, Camden, N.J., and Key West, Fla.; adventive 

 from the West Indies. 



Setaria rariflora Mikan. Similar to S. setosa, the panicle and blades 

 more slender. 01 Mobile, Ala. ; adventive from South America. 

 7. Setaria scheelei (Steud.) Hitchc. (Fig. 1572.) Perennial, 60 

 to 120 cm tall; sheaths compressed-keeled, glabrous or more or less 

 hispid, the collar hispid; blades flat, elongate, as much as 1.5 cm wide, 

 scabrous or more or less pubescent; panicle rather loose, mostly 15 

 to 20 cm long, tapering from near the base, the lower branches as 

 much as 3 cm long, ascending, the axis scabrous-pubescent and rather 



