Yucca brevifolia Engelmann ssp.brevifolia

Joshua Tree

In S. Watson, Botany, King Report, U. S. Geol. ExpI. 40th Par. Rpt. 5: 496. 1871


Yucca draconis var. arborescens Torrey. Pacific R. R. Rpt. 4: 147. 1857.
Yucca arborescens (Torrey) Trelease. Mo. Bot. Gard. Ann. Rpt. 3:163.1892.
Clistoyucca areborescens (Torrey) Trelease. Mo. Bot. Gard. Ann. Rpt. 13: 4.1902.
Clistoyucca brevifolia (Engelmann) Rydberg. Flora Rocky Mountains and Adj. Plains, 1 70.1917.

Type: Bigelow s. n., sandy and gravelly plains west of the Colorado River along the north bank of the Mojave River, near Barstow, San Bernardino Co., California, 15 March 1854 (NY).

Representative material deposited. Seeds, USA, Arizona, Hualapai, 10. January 2001, Fritz Hochstätter, fh 1179.64, University of Heidelberg Herbarium, Institute for Systematic Botany and Plant Geography, Heidelberg (HElD).

Other representative material studied.

Arizona:fh 1178.13, Joshua Tree Parkway,
fh 1178.41, Littlefield, 900 m,
fh 1178.79, Virgin River, 1,150 m,
fh 1179.64, Hualapa Valley, 1,150 m,
fh 1182.73, Gold Basin, 1,200 m.
California:fh 1178.24, Mohave Desert, 1,000 m,
fh 11 78.25, Mohave area, 900 m,
fh 1178.36, Mohave, fh 1181.35, lnyo Mts., 2,300 m,
fh 1181.89, lvanpah Mts., 1,200 m,
fh 1182.63, Hesperia 1,000 m,
fh 1182.64, California Desert,
fh 1182.65, Oro Grande, 600 m,
fh 1182.66, Big Pines, 1,600 m,
fh 1182.67, "kernensis", Red Rock Canyon, 900 m,
fh 1182.72, Cerro Gordo, 2,100 m,
fh 1182.79, Joshua Tree National Park, 600 m,
fh 1183.73, Victorville,
fh 1183.75, Adelanto,
fh 1183.76, "kemensis", Red Rock Canyon area, 1,000 m,
fh 11 83.77 "kernensis", Red Rock Canyon State Park.
Utah:fh 1178.55, Beaver Dam Mts.,
fh 1180.70, Red Mountain, 1,400 m.
Nevada:fh 11 79.65 Oak Springs, 1,800 m,
fh 1182.68, Goldfield, 2,000 m,
fh 1182.69, Silver Peak, 1,800 m,
fh 1182.70, Monitor Range, 1,960 m,
fh 1182.71, Hancock Summit, 1,700 m,
fh 1182.78, Searchlight, 1,200 m,
fh 1183.71, Charleston Peak, 1,600 m,
fh 1183.72, Toyabe National Forest, 1,800 m.

Key to the Subspecies of Yucca brevifolia

1.Tree-like, inflorescence paniculate, leaf margins denticulate, fruit spongy, soon dry.
2.In dense groups with multiple stemsssp. herbertii
Singly or in sparse groups of few stems3
3.5-15 m tall, open branching from 2-3 m heightssp. brevifolia
3-6 m tall, dense branching from 0.5-1 m heightssp. jaegeriana

Yucca brevifolia
Joshua Tree National Park, CAL. A fine specimen of the Joshua tree, Yucca brevifolia, fh 1182.79
with Yucca schidigera, fh 1183.74, growing at its base.

Yucca brevifolia, fh 1183.73, Victorville CAL
The developing inflorescence hidden by the leaf-like lower bracts.

Yucca brevifolia
Yucca brevifolia, fh 1183.75, Adelanto, CAL
Buds with a purplish-red tinge.
Yucca brevifolia
Yucca brevifolia, fh 1182.68, Goldfield, NV, 2,000m.
Flowers in a densely packed cluster, May 2001