Faxon yucca, Spanish dagger

Samuela faxoniana Trelease; Yucca australis Trelease 1893, not (Engelmann) Trelease 1902; Y. macrocarpa Coville 1893, not Engelmann 1881

Plants solitary, erect, arborescent, 2.5–6.9 m, including inflorescence. Stems 1, simple or with 2–4 branches, to 5.1 m, average diam. 32 cm. Leaf blade erect, yellowish green, 43–115 × 3.1–8.4 cm, rigid, smooth, glabrous, margins conspicuous, curling, filiferous, brown. Inflorescences erect, paniculate, often with proximal branches arising beyond rosettes, broadly ovoid, 5.5–25.5 dm, glabrous; peduncle 0.3–0.6 m. Flowers pendent, 4.4–12.4 cm; perianth campanulate; tepals connate basally into floral cup 1–32 mm, white to greenish white, ovate, 3.9–10.8 cm; filaments averaging 2.2 cm from base of tepals, glabrous; anthers 1–6 mm; pistil 2.8–8 × 0.7 cm; ovary ca. 4.5–5 times longer than wide; style 4.5 mm; stigmas distinct. Fruits pendent, baccate, indehiscent, elongate, 3.6–13.6 × 1.8 –3.6 cm, fleshy, succulent. Seeds black, 7.7 mm diam., 2.9 mm thick, smooth.

Flowering late winter--spring. Rocky slopes, flat plains; 800--2100 m; Tex.; Mexico (Chihuahua, Coahuila).

Trelease described the genus Samuela based on two species, Samuela faxoniana and S. carnerosana. K. H. Clary’s DNA study (1997) shows them to be closely related but genetically distinct.

Yucca faxoniana is often used for landscaping in arid and semiarid regions of Texas and New Mexico.