[Illustration: Yucca brevifolia]
Common Names: JOSHUA-TREE, TREE YUCCA, GIANT JOSHUA
California desert. (_Yucca brevifolia_). Green-white. February-April.
Lily family. Size: 15 to 35 feet high; spread of 20 feet.
Because the presence of the grotesque Joshua-tree marks, more
effectively than any other plant, the limits and extent of the Mohave
Desert, this species is worthy of special recognition. This tree Yucca
holds, in the Mohave Desert, similar status to the Saguaro in the
Sonoran Desert. Strangely enough, in west-central Arizona, the Saguaro
and Joshua-tree are found growing together and there the Sonoran and
Mohave Deserts overlap.
And, just as in southern Arizona an area has been set aside as Saguaro
National Monument to preserve and protect that species, so in southern
California we find the Joshua Tree National Monument.
The Joshua-tree is outstanding among the many species of Yucca because
of its short leaves growing in dense bunches or clusters, and because
the plant has a definite trunk with numerous branches forming a crown.
Great forests of these sturdy trees are found in parts of southern
California, southern Nevada, southwestern Utah, and northwestern Arizona
where rainfall averages 8 to 10 inches per year.
Flowers of this Yucca develop as tight clusters of greenish-white buds
at the ends of the branches, but do not open wide as do the flowers of
other Yuccas. Joshua-trees do not bloom every year, the interval
apparently being determined by rainfall and temperature. Birds, a small
lizard, wood rats, and several species of insects are closely associated
with the Joshua-tree, making use of it for food, shelter, or
nest-building materials. Indians use the smallest roots, which are red,
for patterns in their baskets.
The name “Joshua-tree” was given by the Mormons because the tree seemed
to be lifting its arms in supplication as did the Biblical Joshua.