Rep. (Annual) Missouri Bot. Gard. 13: 53, plate 17, fig. 2, plates 18, 19, plate 83, fig. 3, plate 92, fig. 1. 1902.
Plants forming open colonies, acaulescent or short-caulescent; rosettes usually small. Stems erect, to 0.5 m. Leaf blade mostly recurving, lanceolate, plano-convex, widest near middle, 40–70 × 1–2 cm, rigid, margins entire, filiferous, whitish, apex scarcely pungent. Inflorescences paniculate, arising beyond rosettes, ovoid, to 10 dm, distance from leaf tips to proximal inflorescence branches more than twice leaf length when fully expanded, glabrous or slightly pubescent; bracts erect; peduncle scapelike, 1–1.7 m, less than 2.5 cm diam. Flowers pendent; tepals narrow, apex acute; filaments shorter than pistil; pistil 1.5–3.8 cm; ovary white; style white or green, oblong, often deeply lobed; stigmas lobed. Fruits erect, capsular, dehiscent, cylindrical, symmetrical, not constricted, stout, 5–6.5 × 2.5–3 cm, dehiscence septicidal. Seeds glossy black, thin, 8–10 × 7–8 mm.
Phenology: Flowering spring.
Habitat: Brushlands to coast
Elevation: 0–200 m
Very little is known about Yucca tenuistyla, and further study is needed. Along with Y. louisianensis, it was treated by S. D. McKelvey (1938–1947) as a part of Y. constricta. The characteristics separating these three taxa are tenuous, and it is possible that Y. tenuistyla is just a variant of Y. flaccida, which includes Y. louisianensis.