Vascular Plants of the Gila Wilderness
Presented in Association with the
Western New Mexico University Department
of Natural Sciences
Larrea tridentata (Sessé & Mociño ex A.P. de Candolle) Coville var. tridentata
(Creosote Bush)
Family: Zygophyllaceae
Status: Native
Synonyms:
Covillea glutinosa (Engelmann) Rydberg
Covillea tridentata Vail
Larrea mexicana Moricand
Zygophyllanum tridentatum Sesse & Mocino ex A.P. de Candolle
Larrea tridentata is a resinous woody shrub and one of the most abundant components of North American deserts including
the Chihuahuan Desert, and ranges into some of the lowest elevations of the Gila Region.
The small paired leaflets, fused
at their bases, are not symmetrical.
The stipules, at first green, soon become reddish, and secrete copious resin. Stipules
at the growing stem enclose and protect the young meristems (growing tip.) After a rain the aroma of terpenes from the wet
foliage imparts a magical quality to the crisp desert air. The complex aromatic quality of the foliage has long been appreciated
by local people for significant medicinal purposes, including inhalants and poultices, but should not be taken internally due to
toxicity.
The fruit is densely hairy and is the result of a five carpellate ovary that results in five indehiscent hairy nutlets.
Please click on an image for a larger file.
Larrea tridentata, photo Russ Kleinman & Bill Norris, Burro Mtns., Engineer Canyon, Apr. 21, 2007
Larrea tridentata, closeup of fruit, photo Russ Kleinman & Richard Felger, Burro Mtns., Engineer Canyon, Dec. 29, 2008
Larrea tridentata, growth form, photo Russ Kleinman & Richard Felger, Burro Mtns., Engineer Canyon, Dec. 29, 2008
Larrea tridentata, 2x macro of single nutlet, photo Russ Kleinman & Richard Felger, Burro Mtns., Engineer Canyon, Dec. 29, 2008
Larrea tridentata, 2x macro triangular stipules, photo Russ Kleinman & Richard Felger, Burro Mtns., Engineer Canyon, Dec. 29, 2008
Larrea tridentata, closeup of branch, photo Russ Kleinman, Mogollon Mtns., Hwy 180 near Pleasanton, January 15, 2010
Larrea tridentata, 1x macro of bifoliately compound leaf with two small pubescent leaflets fused at the base, photo Russ Kleinman, Mogollon Mtns., Hwy 180 near Pleasanton, January 15, 2010
Back to the Index