Yucca arkansana


Rep. (Annual) Missouri Bot. Gard. 13: 63. 1902.

Common names: Arkansas yucca
Synonyms: Yucca angustifolia var. mollis Engelmann Yucca arkansana var. paniculata McKelvey Yucca glauca var. mollis Engelmann ex Branner & Coville
Treatment appears in FNA Volume 26. Treatment on page 436. Mentioned on page 426, 431, 437, 438.

Plants forming small colonies, acaulescent or caulescent; rosettes usually small. Stems decumbent, short, to 0.2 m. Leaf blade mostly yellowish green, flattened, grasslike, concavo-convex, widest near middle, 20–60(–70) × 0.7–2(–2.5) cm, flexible, margins entire, curled, filiferous, apex long, tapering to short spines 1.6–3.2 mm. Inflorescences racemose, occasionally paniculate proximally, arising within rosettes or at rosette level, 3–6(–8) dm, glabrous; bracts erect; peduncle scapelike, 0.2–0.5(–0.6) m, 0.3–0.7(–1.3) cm diam. Flowers pendent; perianth globose; tepals distinct, greenish white, elliptic to orbicular or oblong, 3.2–6.5 × 2–5 cm; filaments 1.3–2.5 cm; anthers 3.2 mm; pistil 2.5–2.8(–3.2) cm; style dark green, 7–13 mm, tumid; stigmas lobed. Fruits erect, capsular, dehiscent, oblong-cylindric to obovoid, constricted near middle, stout, 4–6.5(–7) × 2–3 cm, dehiscence septicidal. Seeds dull black, thin, ca. 1 cm diam.

Phenology: Flowering spring.
Habitat: Gravelly soil, limestone outcrops, rocky hillsides, prairies
Elevation: 100–400 m


V26 902-distribution-map.jpg

Ark., Kans., Mo., Okla., Tex.


Yucca arkansana shows considerable variation, particularly in the eastern part of its range. S. D. McKelvey (1938–1947) described var. paniculata and suggested that it is an eastern extension of the species with a taller, paniculate, and pubescent inflorescence. Yucca arkansana approaches Y. louisianensis, which we have reduced to synonymy under Y. flaccida. K. H. Clary’s (1997) DNA consensus tree places Y. arkansana and Y. louisianensis adjacent to one another.

Selected References


Lower Taxa

... more about "Yucca arkansana"
William J. Hess +  and R. Laurie Robbins +
Trelease +
Arkansas yucca +
Ark. +, Kans. +, Mo. +, Okla. +  and Tex. +
100–400 m +
Gravelly soil, limestone outcrops, rocky hillsides, prairies +
Flowering spring. +
Rep. (Annual) Missouri Bot. Gard. +
Yucca angustifolia var. mollis +, Yucca arkansana var. paniculata +  and Yucca glauca var. mollis +
Yucca arkansana +
species +