Sierra Blanca Yucca 



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III. SIERRA BLANCA YUCCA 



GENUS SAMUELA TRELEASE 



Species Samuela Faxoniana Trelease 



YiKca macrocarpa Sargent, not Engelmann 



Yucca Faxoniana Sargent 



NOWN only from the vicinity of Sierra Blanca in western Texas, this 

 Yucca-Uke plant probably extends into adjacent Mexico. Its maxi- 

 mum height is about 12 meters, with a trunk diameter of 6 dm. 

 The trunk is usually simple, seldom having a few short branches. 

 The young plants are densely covered with numerous erect or radiating living 

 leaves; later the base is covered by a 

 thatch-like covering of reflexed dead 

 leaves; on old trees the rind is exposed 

 at the base. The rind is about 8 nam. 

 thick, dark reddish brown, and scaly. 

 The leaves are dark green and smooth, 

 linear-oblong, i to 1.25 m. long, stiff and 

 firm, abruptly narrowed just above the 

 thickened, shining red clasping base 

 which is often 1.5 dm. broad, widest at 

 or above the middle and slightly con- 

 cave toward the apex, which is armed 

 with a very sharp, dark tip; the margin 

 separates into grayish threads, which, 

 with the exception of a few coarse fibers 

 near the apex, eventually peel back- 

 ward and form a persistent tangled 

 mass at the base of the leaf. The flowers, which appear in spring, are in short- 

 stalked, broadly conic loosely-branched panicles with persistent white bracts; they 

 are drooping on long stalks, 5 to 10 cm. across; the perianth is funnelfomi, of 

 6 parts, which are broadly lanceolate, sharp-pointed, and curved inwardly at the 

 apex, united at the base into a tube about 8 mm. long, those of the outer series 

 narrower; stamens 6, their filaments shorter than the ovary, club-shaped, hairy, 

 and curved outward; anthers arrow-shaped and horizontal; ovary sessile, narrowly 

 oblong, ridged, yellowish, longer than and narrowed into the slender, grooved style; 

 stigma irregularly 6-lobed. The fruit, which ripens in early summer, is indehiscent, 

 2-5 to 7.5 cm. long, fleshy, pendent, oblong-ovoid, scarcely angled, beaked at the 

 apex, dark yellow and shining, becoming black, the flesh dryish, bitter and sweet; 

 seeds rounded triangular, flat but thick, about 6 mm. long and half as thick, not 

 margined. 



Sierra Blanca Yucca. 



