MANUAL OF THE GRASSES OF THE UNITED STATES 



7. Aristida orcuttiana Vasey. Beg- 

 gartick grass. (Fig. 678.) Perennial; 

 culms erect, 30 to 60 cm. or even 1 

 m. tall; blades flat or the upper in- 

 volute, as much as 3 mm. wide; pan- 

 icle open, as much as 30 cm. long, 

 nodding or drooping, the branches 

 few, distant, spreading or drooping, 

 as much as 20 cm. long; glumes equal 

 or nearly so, 10 to 15 mm. long; 

 lemma 8 to 10 mm. long, gradually 

 narrowed into a scabrous twisted 

 column, the total length to the bend 

 10 to 17 mm.; central awn divergent, 

 5 to 10 mm. long, the lateral awns 

 from obsolete to as much as 1 to 2 

 mm. long, erect. % — Rocky hills 

 and plains, Texas to southern Cali- 

 fornia (San Diego), and northwestern 

 Mexico. 



467 



Section 3. Chaetaria (Beauv.) Trin. 



Lateral awns more than 1 mm. long, 

 usually well developed; lemma 

 not articulate with the column 

 of the awns. 



Figure 679. — Aristida basiramea, X 1. (Pammel 174, 

 Iowa.) 



8. Aristida basiramea Engelm. ex 

 Vasey. (Fig. 679.) Annual; branching 

 at base, 30 to 50 cm. tall; blades flat, 

 as much as 15 cm. long and 1.5 mm. 

 wide; panicles terminal and axillary, 

 the terminal 5 to 10 cm. long, the 



Figure 680. — Aristida dichoto ma, X 1. (Jackson 1829, 

 Del.) 



axillary mostly enclosed in the 

 sheaths; glumes somewhat unequal, 

 12 to 15 mm. long; lemma about 1 

 cm. long; central awn coiled at base, 

 10 to 15 mm. long, the lateral awns 

 half to two-thirds as long, somewhat 

 spreading. O — Open barren or 

 sandy soil, Maine to North Dakota, 

 south to Kentucky, Oklahoma, and 

 Colorado; introduced in Maine. 



9. Aristida dichotoma Michx. (Fig. 

 680.) Annual; culms branched at base, 

 20 to 40 cm. tall; blades short, the 

 lower mostly flat, scarcely 1 mm. 

 wide, the upper involute; panicles 

 terminal and axillary, the terminal 

 usually less than 10 cm. long, the 

 lateral small; glumes about equal, 6 

 to 8 mm. long; lemma 5 to 6 mm. 

 long; central awn spirally coiled, 

 horizontally bent, 3 to 6 mm. long, 

 the lateral awns erect, about 1 mm. 

 long. O — Dry open ground, 

 Maine to Wisconsin and eastern Kan- 

 sas, south to Florida and Texas. 



10. Aristida curtissii (A. Gray) 

 Nash. (Fig. 681.) Annual; similar to 

 A. dichotoma, differing in the less 

 branching habit, the longer and more 



