Yucca brevifolia

Engelmann

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

Common names: Joshua tree
IllustratedEndemic
Basionym: 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.

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.

Selected References

None.

Lower Taxa

None.

"thick" is not a number. "thin" is not a number."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property."thin" is not a number.

... more about "Yucca brevifolia"
longitudinal +
short-pubescent +
papillate +
0.3 cm3 mm <br />0.003 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
glandular-pubescent +  and glandular +
sharp-pointed +
William J. Hess +  and R. Laurie Robbins +
Engelmann +
Yucca draconis var. arborescens +
elliptic +, ovate +, oblanceolate +, lanceolate +  and linear +
expanded +
fleshy +  and rigid +
reflexed +, erect +  and ascending +
scale-like +
100 cm1,000 mm <br />1 m <br /> (300 cm3,000 mm <br />3 m <br />) +
Joshua tree +
Ariz. +, Calif. +, Nev. +  and Utah. +
400–1800 m +
elongated +
pubescent +  and glabrous +
flattened +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
broadened +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
furrowed +  and capsular +
indehiscent +
ellipsoid +
6 cm60 mm <br />0.06 m <br /> (8.5 cm85 mm <br />0.085 m <br />) +
Deserts +
crowded +  and paniculate +
ellipsoid-ovoid +
15 cm150 mm <br />0.15 m <br /> (35 cm350 mm <br />0.35 m <br />) +
0.7cm;1.5cm +
long-lived +  and annual +
denticulate +
longer than broad +
2.5 cm25 mm <br />0.025 m <br /> (?) +  and 3 cm30 mm <br />0.03 m <br /> (?) +
not +  and articulate +
oblong-ellipsoid +  and globose +
semisucculent +
Flowering late winter–mid spring. +
oblong-cylindrical +  and obovoid +
2 cm20 mm <br />0.02 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
in S. Watson, Botany (Fortieth Parallel), +
0 cm0 mm <br />0 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
ovate +, obovate +, round +  and flattened +
Illustrated +  and Endemic +
exserted +  and included +
branched +  and simple +
aboveground +  and subterranean +
several +  and many +
white;pale green +
1 +  and 3 +
list +  and count +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
white +  and dark green +
exserted +  and included +
1.6 cm16 mm <br />0.016 m <br /> (?) +
Cleistoyucca arborescens +, Cleistoyucca brevifolia +, Yucca arborescens +, Yucca brevifolia var. herbertii +  and Yucca brevifolia var. jaegeriana +
Yucca brevifolia +
species +
greenish white;cream +
2.5cm +  and 7cm +
lanceolate +  and oblong +
1.1cm;2.2cm +
branching +, subscapose +, caulescent +  and acaulescent +
aboveground +  and subterranean +
polygamodioecious +, dioecious +, monoecious +, polycarpic +  and monocarpic +
small;gigantic +
petal-like +