142 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



Where it is sufficiently abundant this grass supplies forage of good 

 quality. 



65. LEPTOLOMA. Fall-witchgrass 



Slender perennial, felty-pubescent at base, with branching brittle 

 culms, flat leaf blades, and diffuse panicles; first glume minute or 

 obsolete; second glume and sterile lemma nearly equal, appressed- 

 hairy on the internerves and margins; fertile lemma elliptic, acute,, 

 brown. 



1. Leptoloma cognatum (Schult.) Chase, Biol. Soc. Wash. Proc. 19: 

 192. 1906. 



Panicum cognatum Schult., Mant. 2 : 235. 1824. 



Cochise, Santa Cruz, and Pima Counties, up to 5,000 feet, rocky 

 slopes and gravelly plains, August to September. New Hampshire tO' 

 Minnesota, south to Florida, Texas, southern Arizona, and northern 

 Mexico. 



The mature panicles break away and become " tumble weeds.' ' The 

 species is a fairly palatable forage plant. 



66. ERIOCHLOA. Cupgrass 



Erect or decumbent annuals with flat leaf blades and several to 

 numerous erect or ascending racemes, approximate on a common axis; 

 spikelets usually solitary in two rows on one side of a narrow rachis; 

 second glume and sterile lemma equal, longer than the fruit, the 

 lemma sometimes enclosing a palea or a staminate flower; fertile 

 lemma indurate, minutely rugose, mucronate or awned. 



Key to the species 

 1. Pedicels with erect hairs at least half as long as the spikelets. 



1. E. LEMMONI. 



1. Pedicels pubescent or scabrous (2). 



2. Second glume and sterile lemma awned; spikelets, including the awns, 7 to 10 



mm. long 2. E. aristata. 



2. Second glume and sterile lemma awnless or mucronate; spikelets not more 

 than 6 mm. long (3) . 



3. Fruit 3 mm. long, apiculate 3. E. gracilis. 



3. Fruit 2 to 2.5 mm. long, with an awn 0.5 to 1 mm. long (4) . 



4. Spikelets 3 to 3.5 mm. long, the second glume merely acute; rachis 



slender, pubescent 4. E. procera. 



4. Spikelets, including the awn of the second glume, 4.5 to 5 mm. long; 

 rachis relatively stout, scabrous 5. E. contracta. 



1. Eriochloa lemmoni Vasey and Scribn., Bot. Gaz. 9: 185. 1884. 

 Cochise, Santa Cruz, and Pima Counties, 4,000 to 5,000 feet, rocky, 



grassy slopes, August to September, type from the Huachuca Moun- 

 tains (Lemmon 2910). Southern Arizona and northern Mexico . 



2. Eriochloa aristata Vasey, Torrey Bot. Club Bui. 13: 229. 1886. 

 Open ground around Tucson, Pima County (Thornber 98, Griffiths 



1612, 6943) . Arizona, California, and northern Mexico. 



3. Eriochloa gracilis (Fourn.) Hitchc, Wash. Acad. Sci. Jour. 23: 455. 



1933. 



Helopus gracilis Fourn., Mex. PL 2 : 13. 1886. 



Yavapai, Pinal, Cochise, Santa Cruz, and Pima Counties, 2,500 to 

 5,200 feet, moist open ground, June to October. Texas, New Mexico, 

 and Arizona. 





