FLOWERING PLANTS AND FERNS OF ARIZONA 199 



touch, 60 to 75 cm. long, rigid, not twisted, the marginal fibers loosely curled and 

 moderately fine. Tvpe from about 15 miles northeast of Douglas, Cochise 

 County, 4,500 feet (SlcKelvey 2099). 



9. Yucca arizonica McKelvev, Arnold Arboretum Jour. 16: 270. 

 1935. 



Yucca treleasei Macbride, Gray Herbarium Contrib. 56: 15. 

 1918. Not Sprenger, 1901. 



Pinal, Cochise, Pima, and Santa Cruz Counties, 3,500 to 5,000 feet, 

 abundant in the Baboquivari Mountains and around Nogales, April and 

 May, type from Santa Cruz County. Southern Arizona and Sonora. 



Stems up to 2.5 m. long; leaves 30 to 60 cm. long, 15 to 25 mm. 

 wide, rather rigid; panicle obovoid (pi. 12). 



Yucca thornberi McKelvev, occupying nearly the same general range as Y- 

 arizonica, is distinguished by the following characters: stems only up to 1.5 m. 

 long; the leaves up to 100 or even 130 cm. long, more flexible than in Y. arizo- 

 nica; and the inflorescence less exserted, ellipsoidal. 



15. NOLINA. 24 Beargrass 



Plants with a large woody caudex, this subterranean or forming a 

 distinct trunk above ground; leaves numerous, clustered, long and 

 narrow; flowers perfect and unisexual, very numerous, in ample 

 terminal panicles; capsule 3-lobed; seed 1 in each cell, turgid. 



It is reported that sheep and goats sometimes are poisoned by these 

 plants. 



Key to the species 



1. Plant acaulescent; leaves 3 to 12 mm. wide; fruit 6 to 8 mm. long, the seed 

 exposed after dehiscence 1. X. microcarpa. 



1. Plant caulescent; leaves 15 to 35 mm. wide; fruit up to 15 mm. in diameter, 

 greatly inflated, the seed not exposed; trunk 1 to 2 meters high, clothed with 

 dead leaves 2. X. bigelovii. 



1. Nolina microcarpa S. Wats., Amer. Acad. Arts and Sci. Proc. 14: 



247. 1879. 



Nearly throughout the State, common in the central and south- 

 eastern counties, usually in exposed situations on mountainsides, 

 about 3,000 to 6,500 feet, May and June, type from southeastern 

 Arizona. New Mexico, Arizona, and northern Mexico. 



The caudex and emerging flower stalk apparently were prepared for 

 food by the Indians in the same way that the corresponding parts of 

 Agave and Yucca were used. The leaves are browsed in times of 

 drought. 



Xolina affinis Trelease (N. caudata Trelease) related to A T . texana Wats., is 

 distinguished from N. microcarpa by the seed protruding conspicuously after 

 dehiscence, inflorescence usually scabrous, and leaves often with smooth margins. 

 Several collections from Santa Cruz and Cochise Counties are cited by Trelease. 



2. Nolina bigelovii (Torr.) S. Wats., Amer. Acad. Arts and Sci. Proc. 



14: 247. 1879. 



Dasylirion bigelovii Torr., U. S. Rpt. Expl. Miss. Pacif. 4: 151. 

 1857. 



Mohave, western Yavapai, and Yuma Counties, not uncommon, 

 up to at least 3,400 feet, hills and canyons, type from Williams River. 



24 Reference: Trelease, W. the desert group xolixeae. Amer. Phil. Soc. Proc. 50: 406-426. 1911. 



