Yucca brevifolia

Engelmann

in S. Watson, Botany (Fortieth Parallel), 496. 1871

Common names: Joshua tree
Basionyms: Yucca draconis var. arborescens Torrey Pacif. Railr. Rep. 5(4): 147. 1857
Synonyms: Cleistoyucca arborescens (Torrey) Trelease Cleistoyucca brevifolia (Engelmann) Rydberg Yucca arborescens (Torrey) Trelease Yucca brevifolia var. herbertii (J. M. Webber) Munz Yucca brevifolia var. jaegeriana McKelvey
Treatment appears in FNA Volume 26. Treatment on page 426. Mentioned on page 421, 424, 427.
Click plate for higher resolution version.
Illustrator: Bee F. Gunn
Plants usually solitary, erect, arborescent, to 15 m. Stems usually 1, occasionally several–many, simple or usually branched distally; branches 1–3 m. Leaf blade green, 15–35 × 0.7–1.5 cm, rigid, smooth, glabrous, margins nearly entire, minutely denticulate, yellow. Inflorescences erect, paniculate, densely crowded, ca. 1/2 enclosed in rosettes, ellipsoid-ovoid, 3–5.5 × 3–3.8 dm, glabrous. Flowers erect, 4–7 cm; perianth oblong-ellipsoid to globose; tepals barely connate at base, greenish white to cream, lanceolate to oblong, 2.5–7 × 1.1–2.2 cm; filaments 1–1.2 cm; anthers 3–3.2 mm, short-pubescent to papillate; pistil 2–3.5 cm; ovary ovoid, 2.5–3 cm, longer than broad; style ca. 1.6 mm; stigmas distinct. Fruits pendent, capsular, indehiscent, deeply furrowed, ellipsoid, 6–8.5 cm, dry, spongy. Seeds dull black, thin, 8–12 mm diam., smooth.

Phenology: Flowering late winter–mid spring.
Habitat: Deserts
Elevation: 400–1800 m

Distribution

V26 871-distribution-map.jpg

Ariz., Calif., Nev., Utah.

Discussion

There is disagreement regarding the status of entities within Yucca brevifolia. S. D. McKelvey (1935) described var. jaegeriana, the miniature Joshua tree, and L. D. Benson and R. A. Darrow (1981) recognized the variety as well; however, J. L. Reveal (1977c) declined to recognize it, a decision with which we agree.

References

None.

Lower Taxa

No lower taxa listed.