familyAgavaceae
genusYucca

Yucca pallida

McKelvey

Yuccas Southw. U.S. 2: 57, plates 13, 14. 1947.

Common names: Pale yucca
Endemic
Synonyms: Yucca pallida var. edentata (Trelease) Cory Yucca rupicola var. edentata Trelease
Treatment appears in FNA Volume 26. Treatment on page 431. Mentioned on page 425, 438.

Plants forming loose colonies of rosettes, acaulescent, with branching subterranean caudices; rosettes 10–30 per colony, each rosette with fewer than 100 leaves. Leaf blade lanceolate, straight, flat except becoming concave near apex, widest above middle, 20–50 × 1–4.5 cm, flexible, glaucous, margins denticulate or sometimes wavy, yellow. Inflorescences paniculate, often distally racemose, arising beyond rosettes, 7–12 dm, with wide-spreading branchlets 1.5–2.3 dm; bracts erect; peduncle scapelike, 0.6–1.3 m, less than 2.5 cm diam., glaucous. Flowers pendent; perianth campanulate; tepals distinct, greenish white, elliptic to ovate, 5–6.5 × 2–3.2 cm; filaments 1.8–3.2 cm; pistil 3.2–4 cm; style white, 13–20 mm; stigmas lobed. Fruits erect, capsular, dehiscent, oblong-cylindric, 4.5–5.5 × 1.3–2 cm, dehiscence septicidal. Seeds dull black, thin, 5–7 mm diam.


Phenology: Flowering spring.
Habitat: Rocky prairies and uplands, rarely limestone hills
Elevation: 100–400 m

Discussion

Yucca pallida is endemic to the blackland prairies of Texas and was originally included in Y. rupicola. J. M. Webber (1953) indicated that he found plants of Y. rupicola with key features similar to those of Y. pallida. Occasionally, plants with entire margins are found; these have been called Y. pallida var. edentata, which S. D. McKelvey (1938–1947) suggested might be a hybrid between Y. pallida and Y. arkansana. K. H. Clary (1997) indicated that DNA evidence confirms the close relationship of Y. pallida and Y. rupicola.

Selected References

None.

Lower Taxa

None.