400 MISC. PUBLICATION 200, TJ. S. DEPT. OF AGRICULTURE 



pediceled; glumes acute, the first 2 to 3 mm, the second 4 to 6 mm 

 long; lemma and palea acute, about equal. % — Grassy plains and 

 hills, Arizona. The second glume and lemma may have wrinkles 

 toward the summit that look like nerves. 



12. Sporobolus heterolepis A. Gray. 

 Prairie dropseed. (Fig. 830.) Per- 

 ennial, in dense tufts; culms erect, 

 slender, 30 to 70 cm tall; sheaths 

 somewhat pilose at the throat, the 

 lower sometimes sparsely pilose on the 

 back; blades elongate, flat, becoming 

 involute at the slender attenuate tip, 

 2 mm or less wide; panicle, 5 to 20 

 cm long, the branches ascending or 

 spreading, 3 to 6 cm long, naked be- 

 low, few-flowered above; spikelets 

 grayish; glumes acuminate, the first 

 2 to 4 mm long, the second 4 to 6 mm 

 long; lemma snorter than the second 

 glume, palea slightly longer than the ^ r 

 lemma; caryopsis globose, nutlike, aJ| 

 nearly 2 mm thick, finally splitting 



Figure 828.— Distribution of 

 Sporobolus clandestinus. 



the palea. % — Prairies, Quebec to 

 Saskatchewan and Wyoming, south 

 to Connecticut, Illinois, Arkansas, and 

 eastern Texas (fig. 831). 



13. Sporobolus curtissii (Vasey) 

 Small. (Fig. 832.) Perennial, in dense 

 tufts; culms slender, 30 to 70 cm tall; 

 basal sheaths pilose at the throat; 

 blades flat or folded, flexuous, about 

 1 mm wide, pilose on the upper sur- 

 face near the base ; panicle pyramidal, 

 open, 7 to 20 cm long, the branches 

 solitary or in twos, ascending ; spike- 

 lets appressed along the main branch- 

 es, bronze or purplish, about 4.5 mm 

 long; glumes about equal, acuminate, 

 as long as or longer than the lemma 

 and palea. % — Dry pine barrens, 

 North Carolina, Georgia, and Florida. 



14. Sporobolus teretifolius Harper. (Fig. 833.) Perennial, in 

 tufts; culms erect, wiry, 60 to 80 cm tall, sheaths pilose at the throat; 

 blades elongate, slender, terete, wiry, flexuous, pilose on the upper 

 surface at base; panicle pyramidal, open, 15 to 20 cm long, the capil- 







Figuee 829.— Sporobolus interruptus. Plant, X 

 1; glumes and floret, X 10. (Rusby, Ariz.) 





