MANUAL OF THE GRASSES OF THE UNITED STATES 



417 



4. Sporobolus neglectus Nash. 

 (Fig. 593.) Differing from S. vagini- 

 florus chiefly in the smaller, paler, 

 plumper spikelets, 2 to 3 mm. long, 

 and in the glabrous lemma; lower 

 blades often sparsely pilose; panicles 

 usually entirely hidden in the more 

 swollen sheaths. O — Dry open 

 ground and sandy fields, Quebec and 

 Maine to Montana, south to Virginia, 

 Tennessee, and Texas; also Washing- 

 ton and Arizona. A form from Mis- 

 souri (Ozark Mountains), with rather 

 strongly pilose leaves, has been differ- 

 entiated as S. ozarkanus Fernald. 



5. Sporobolus asper (Michx.) 

 Kunth. (Fig. 594.) Perennial; culms 

 erect, often rather stout, solitary or 

 in small tufts, 60 to 120 cm. tall; 

 blades elongate, flat, becoming invo- 

 lute, 1 to 4 mm. wide at base, taper- 

 ing to a fine point; panicle terminal 

 and axillary, pale or whitish, some- 

 times purplish, contracted, more or 

 less spikelike, usually enclosed at base 

 or sometimes entirely in the inflated 

 upper sheath, 5 to 15 cm. long; spike- 

 lets 4 to 6 mm. long; glumes rather 

 broad, keeled, subacute, the first 

 about half as long as the spikelet, the 

 second two-thirds to three-fourths as 

 long; lemma and palea subequal, gla- 

 brous, the tip boat-shaped. % — 

 Prairies and sandy meadows, Ver- 

 mont to Montana, south to Louisiana 

 and Arizona; eastern Washington. 



Sporobolus asper var. pilosus 

 (Vasey) Hitchc. Sheaths and blades 

 more or less pilose. % (S. pilosus 

 Vasey.) — Prairies and rocky hills, 

 Kansas (Saline County and west- 

 ward), Texas (Del Rio), and Mon- 

 tana. 



Sporobolus asper var. hookeri 

 (Trin.) Vasey. Less robust, the more 

 slender, fewer flowered, panicle looser; 

 spikelets usually smaller, 3 to 5 mm. 

 long. 91 (S. attenuatus Nash; S. 

 drummondii Vasey.) — Plains, Mis- 

 souri, Kansas, Mississippi, Texas, and 

 Oklahoma. Foliage rarely somewhat 

 villous. 



6. Sporobolus macer (Trin.) 

 Hitchc. (Fig. 595.) Perennial, with 



Figure 595. — Sporobolus macer. Plant, X Yi\ glumes 

 and floret, X 10. (Chase 4341, Miss.) 



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 en- 

 closed at base, 5 to 15 cm. long, the 

 branches erect; spikelets 4 to 5 mm. 



