MANUAL OF THE GRASSES OF THE UNITED STATES 471 



Lemmas awnless or mucronate only. 

 Florets obtuse, sometimes mucronate. 



Spikelets 5 to 7 mm long, 6- to 9-flowered, lead color. 



L.UN1NERVIA. 

 L. XEALLEYI. 



Spikelets 2 to 3 mm long, 3- to 4-flowered, pale 



Florets acuminate. 



Sheaths scabrous, keeled and compressed 10. L. scabra. 



Sheaths smooth or slightlv scabrous near apex, scarcely keeled or 

 compressed H- L - panicoides. 



Figure 1009.— Leptochloa dubia. 



Panicle, X 1; two views of floret, X 10. 

 3572, Fla.) 



(Small, Carter, and Small 



Figure 1010.— Distribution of 

 Leptochloa dubia. 



1. Leptochloa dubia (H. B. K.) Nees. Green sprangletop. (Fig. 

 1009.) Perennial; culms wiry, erect, 50 to 100^ cm tall; sheaths 

 glabrous; blades flat or sometimes folded or loosely involute, scabrous, 

 as much as 1 cm wide, but usually narrower; panicle of few to many 

 spreading or ascending racemes 3 to 12 cm long, approximate or 

 somewhat distant on an axis as much as 15 cm long; spikelets 5- to 



8-flowered or in reduced specimens only 2-flow- 

 ered, 5 to 10 mm long; lemmas broad, glabrous 

 on the internerves, obtuse or emarginate, the 

 midnerve sometimes extending into a short 

 point, the florets at maturity widely spreading, 

 very different in appearance from their early 

 phase. % — Rocky hills and canyons and 

 sandy soil, southern Florida; Oklahoma (Fort 

 Sill) and Texas to Arizona, south through 



Mexico; (fig. 1010) Argentina. Racemes of cleistogamous spikelets 



are often found in the sheaths. 



2. Leptochloa chloridiformis (Hack.) Parodi. (Fig. 1011.) Robust 

 tufted perennial, somewhat glaucous; culms erect, 80 to 150 cm tall; 

 sheaths scaberulous; ligule a dense line of white hairs, 1 to 2 mm long; 

 blades erect, elongate, flat, rather firm, 3 to 4 mm wide, villous on the 

 upper surface near the base, the margins scabrous, long-attenuate; 

 panicle long-exserted ; spikes numerous (usually 10 to 15), pale or 

 stramineous, erect at base, flabellate or outcurved above, 10 to 15 

 cm long, aggregate in 2 or 3 whorls on an axis 3 to 4 cm long; spikelets 

 closely imbricate on a rachis 0.5 mm wide, about 4-flowered, about 

 4 mm long; glumes acute, the first 1.5 mm long, the second 2.5 to 

 3 mm long; lemmas keeled, pilose on the margins nearly to apex, 

 the midnerve extending beyond the obtuse tip as a minute mucro, 

 the first and second florets about 3 mm long, the other shorter, not 



