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-fiowered, lead color. 



8. L.UN1NERVIA. 



Spikelets 2 to 3 mm long, 3- to 4-flowered, pale 9. L. nealleyi. 



Florets acuminate. 



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



Sheaths smooth or slightly scabrous near apex, scarcely keeled or 

 compressed 11. L. panicoides. 



Figure 1009.— Leptochloa dubia. 



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

 3572, Fla.) 



(Small, Carter, and Small 



g- 



Figure 1010. — Distribution of 

 Leptochloa dubia. 



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

 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. 21 — 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 



