732 



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



10 mm long, the awn 8 to 12 mm long; pedicellate spikelet scarcely 

 reduced, short-awned. % — Sandy islands along the Gulf coast, 

 western Florida, Mississippi (Horn Island), and Louisiana (Last 

 Island). 



10. Andropogon divergens (Hack.) Anderss. (Fig. 1633.) Culms 

 rather robust, 80 to 120 cm tall, sparingly branching toward the sum- 

 mit; sheaths grayish villous, the lower crowded, compressed-keeled; 



blades rather firm, 3 to 6 mm wide, villous, 

 elongate, flat or folded; raceme mostly 3 to 

 4 cm long, mostly 6- to 8-jointed, rather 

 stout, usually partly included, the rachis 

 slightly to strongly flexuous, rather stout, the 

 joints and pedicels long-ciliate on the upper 

 half and with a short tuft of hairs at base; 

 sessile spikelet 6 to 8 mm long, minutely 

 roughened, the awn 5 to 10 mm long; 

 pedicellate spikelet about as long as the 

 sessile one, the first glume \ 



awn-tip ped. % — 

 Pinelands, Texas. 



Section 2. Arthrolophis 

 Trin. 



Branching perennials ; ra- 

 cemes 2 to few on each 

 peduncle; rachis joints 

 slender, mostly pubes- 

 cent; sessile spikelet 

 awned. 

 11. Andropogon furca- 



tus Muhl. Bluejoint 



TURKEYFOOT. (Fig. 1634.) 



Plants often glaucous; 



culms robust, often in 



large tufts, sometimes 



with short rhizomes, 1 to 



2 m tall, usually spar- 

 ingly branching toward 



the summit; lower 



sheaths and blades some- 

 times villous, occasionally 



densely so, the blades 



flat, elongate, mostly 5 to 



10 mm wide, the margins 



very scabrous; racemes 



on the long-exserted 

 terminal peduncle mostly 3 to 6, fewer on the branches, 5 to 10 cm 

 long, usually purplish, sometimes yellowish; rachis straight, the joints 

 and pedicels stiffly ciliate on one or both margins, the joints hispid 

 at base; sessile spikelet 7 to 10 mm long, the first glume slightly sul- 

 cate, usually scabrous, the awn geniculate and tightly twisted below, 

 1 to 2 cm long; pedicellate spikelet not reduced, awnless, staminate. 



Figure 1631.— Andropogon stoloni 

 hr, X 1. (Fredholm 6122, Fla.) 



Figure 1632.— Andropogon mariti 

 mus, X 1. (Chapman, Fla.) 



Figure 1633.— Andropogon 

 divergens, X 1. (Tharp 

 3094, Tex.) 



