Introductory
SPECIES: Yucca brevifolia | Joshua Tree 



ABBREVIATION : 
YUCBRE

SYNONYMS : 
   Yucca brevifolia var. wolfei Jones
   Yucca draconis var. arborescens Torr.
   Yucca arborescens (Torr.) Trel.


SCS PLANT CODE : 
   YUBR


COMMON NAMES : 
   Joshua tree
   Joshua-tree yucca
   tree yucca
   yucca-palm


TAXONOMY : 
The currently accepted scientific name for Joshua tree is Yucca
brevifolia Engelm.  The Yucca genus is both variable and unstable [44].
Natural hybridization is common, and numerous intermediate forms occur
[43].  This genus has received only limited attention [10], and many
taxonomic questions persist.  Currently recognized varieties of Joshua
tree are as follows [28]:

            Yucca brevifolia var. brevifolia
            Yucca brevifolia var. jaegeriana McKelvey
            Yucca brevifolia var. herbertii (J. M. Weber) Munz

Webber [43] first delineated the form herbertii on the basis of
morphological differences.  Munz [28] found these differences to be
significant enough to distinguish this entity as a variety, var.
herbertii (J. M. Webber) Munz.  Today, however, several researchers
question all of the varieties named by McKelvey [26], Munz [28], Webber
[43], and others.  Cronquist and others [10] found little evidence to
delineate any varieties.  This controversy points out the need for
additional research on this complex but fascinating group.


LIFE FORM : 
Tree

FEDERAL LEGAL STATUS : 
No special status

OTHER STATUS : 
NO-ENTRY


COMPILED BY AND DATE : 
D. Tirmenstein, March 1989.


LAST REVISED BY AND DATE : 
NO-ENTRY


AUTHORSHIP AND CITATION : 
Tirmenstein, D. 1989. Yucca brevifolia. In: Remainder of Citation

Related categories for Species: Yucca brevifolia | Joshua Tree