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



-Sporobolus 

 and floret, 



as per. 

 X 10. 



Plant, X 

 (Deam 



Sporobolus asper var. pilosus 

 (Vasey) Hitchc. Sheaths and blades 

 more or less pilose. 01 (S. pilosus 

 Vasey.) — Prairies and rocky hills, Kansas 

 (Saline County and westward), Texas 

 (Del Rio). 



Sporobolus asper var. hookeri 

 (Trin.) Vasey. Less robust, the more 

 slender fewer-flowered panicle looser; 

 spikelets usually smaller, 3 to 5 mm 

 long. 01 (S. attenuatus Nash; S. 

 drummondii Vasey.) — Plains, Missouri, 

 Mississippi, Texas, and Oklahoma. 

 Foliage rarely somewhat villous. 



9. Sporobolus macrus (Trin.) Hitchc. 

 (Fig. 826.) Perennial, with short scaly 

 rhizomes; culms erect, 50 to 70 cm 

 tall; blades flat, 10 to 20 cm long, 1 

 to 2 mm wide, sometimes wider, pilose 

 on the upper surface near base and 

 at the throat of the sheath; panicle 

 narrow, often enclosed at base, 5 to 15 

 cm long, the bran- 

 ches erect; spike- 

 lets 4 to 5 mm long, 

 the glumes keeled, 

 the first about 

 two-thirds as long, 

 the second a little 

 longer than the 

 first; lemma and 

 palea subequal, the tips boat-shaped. 

 Ol — Wet pineland, Oklahoma, Mis- 

 sissippi, and Louisiana. Except for 

 the rhizomes this species resembles S. 

 asper var. hookeri. 



10. Sporobolus clandestinus (Spreng.) 

 Hitchc. (Fig. 827.) Perennial; culms 

 relatively stout to slender, erect to 

 spreading, 50 to 100 cm tall; lower 

 sheaths sometimes pilose; blades flat, 

 becoming involute, with a long fine 

 point; panicle narrow, contracted, 5 to 

 10 cm long, usually partly enclosed; 

 spikelets 5 to 7 mm long, the glumes 

 keeled, acute or subacute, the first more 

 than half as long as the spikelet, the 

 second longer than the first; lemma 

 sparsely appressed-pubescent, acuminate, 

 the palea longer, sometimes as much as 

 lOmmlong. 0[ (S.canovirens Nash.) — 

 Sandy fields, pine barrens, hills, and prai- 

 ries, Connecticut to Illinois and Kansas, 

 south to Florida and Texas (fig. 828). 



Figure 825.— Distribution of 

 Sporobolus asper. 



