FLOWERING PLANTS AND FERNS OF ARIZONA 131 



47. HILARIA 



Stiff perennials with solid culms and narrow leaf blades, the groups 

 of spikelets in rather narrow, dense terminal spikes; spikelets in groups 

 of 3, the central spikelet fertile, 1 -flowered, the lateral ones staminate, 

 2-flowered; glumes of the 3 spikelets firm, forming a false involucre; 

 lemma and palea equal, hyaline. 



On Arizona ranges this genus is second in importance only to the 

 gramas (Bouteloua spp.). Although not so palatable as the latter, 

 the plants are better able to withstand close grazing and trampling. 

 Curly-mesquite (H. belangeri) abounds on dry open foothills. Galleta 

 (H. jamesii) is perhaps the most characteristic and important forage 

 grass on the Navajo Indian Reservation and is inferior only to blue 

 grama (Bouteloua gracilis) on the higher grasslands in the northern 

 part of the State. Its place is taken in the southeastern grassland by 

 tobosa (H. mutica). This species and big galleta (H. rigida) attain 

 fullest development in depressions or on heavy alluvial soil. H. 

 jamesii is used by the Hopi Indians as a fill for basketry and in making 

 ceremonial articles. 



Key to the species 



1. Culms tufted, sending out slender, wiry stolons, the internodes 5 to 15 cm. 



long 1. H. BELANGERI. 



1. Culms not stoloniferous, erect from a stout decumbent or rhizomatous base (2) . 



2. Culms felty pubescent 2. H. rigida. 



2. Culms glabrous (3). 



3. Glumes of the lateral spikelets narrowed toward the apex. 



3. H. JAMESII. 

 3. Glumes of the lateral spikelets conspicuously widened toward the sub- 

 hyaline apex 4. H. MUTICA. 



1. Hilaria belangeri (Steud.) Nash, North Amer. Fl. 17: 135. 1912. 



Anthephora belangeri Steud., Syn. PL Glum. 1: 111. 1854. 



Yavapai, Gila, Pinal, Maricopa, Cochise, Santa Cruz, and Pima 

 Counties, 1,500 to 6,000 feet, mesas and foothills, May to September. 

 Texas to Arizona and northern Mexico. 



The var. longifolia (Vasey) Hitchc, a form with erect culms, elongate- 

 blades, and without rhizomes, is found on rocky hills around Tucson. 

 The species is referred to H. cenchroides in Woot. and Standi., Flora 

 of New Mexico. (Contrib. U. S. Natl. Herbarium 19: 53. 1915.) 



2. Hilaria rigida (Thurb.) Benth. ex Scribn., Torrey Bot. Club Bui. 9: 



86. 1882. 



Pleuraphis rigida Thurb. in S. Wats., Bot. Calif. 2: 293. 1880. 



Mohave, Yavapai, Pinal, Maricopa, and Yuma Counties, up to 

 4,000 feet, deserts, plains, and rocky hills, February to September. 

 Southern Utah and Nevada to Arizona, southern California, and 

 Sonora. 



3. Hilaria jamesii (Torr.) Benth., Linn. Soc. London Jour. Bot. 19: 



62. 1881. 



Pleuraphis jamesii Torr., Ann. Lye. N. Y. 1: 148. 1824. 



Apache, Navajo, Coconino, Mohave, and Cochise Counties, 4,500 

 to 7,000 feet, dry hills, rocky canyons, and sandy plains, May to 

 September. Wyoming to Nevada, south to Texas, Arizona, and Cal- 

 ifornia. 



