Cylindropuntia acanthocarpa (Englem. & Bigelow) I.M. Kunth 1935

by Mead Zaccagni Mier, Native Plants Class 2003
Common names: Buckhorn Cholla, Yellow flowered cane cactus, Deer-horn cactus, Staghorn Cholla; Spanish: Tasajo, Cholla.
Family: Cactaceae
Synonymy: Opuntia acanthocarpa (Englem. & Bigelow,1856)
Etymology: Clylindro means cylindrical shape (8). Opuntia is a Greek name first used by Pliney for a plant that was actually not a cactus which grew around the town of Opus in Greece (3). Acanthocarpous is Greek for ‘thorny fruited’. Its form gives rise to the common name Buckhorn (8).

Identification
Growth form: Buckhorn Cholla is considered a shrub/ subshrub cactus that is on average .9-1.8 m in height and can grow up to 4 m tall (5,6,7).
Roots: Relatively large roots in a shallow root system. Dropped segments will send out new roots to the ground (6).
Stem: Buckhorn Chollas are multibranched arising from the ground or from a short trunk (6). Stems are 15 to 30 cm long, 1.5 to 3 cm in diameter, green and very tuberculate (4). Tubercles are elongated and flattened laterally (1). Stems are photosynthetic. Tissue is fleshy for water storage (8).
Leaves: Leaves are modified into 7-25 yellow to dark brown spines per areole. Spines are 2 to 3 cm long and covered with straw colored sheaths (1,4,5).
Inflorescence/flowers: Red, purple, yellow, orange, pink, greenish, or brownish spirally arranged flowers with dark red anthers. Flowers are large, having a 2.5-3 cm diameter (1,5,6,8).
Fruit: Seed propagation as well as vegetative. Lower part is spineless while upper fruit has 10 to 16, wide, long, tan-brown, barbed spines per areole. Fruits are oval berries, deeply tuberculate, dry when ripe, and fall from plant after several months, but before winter. Seeds are 6 mm in diameter, angular and tan (1,4,5,6,8).
Similar species: Cylindropuntia versicolor is frequently mistaken for the Buckhorn Cholla although the former is usually shorter, more frequently tinged red or purple in winter, has smaller fruits, and is found at lower elevations (6).

Ecology
Life history: Perennial (7)
Native/introduced: Native to Sonora Mexico, southern Utah, southeast California, Nevada, and Arizona (1,5,7).
Photosynthetic pathway: CAM
Phenology: Flowers in Spring, between April and June (4,5).
Distribution: Grows in rocky and sandy slopes as well as washes at 153 m to 1800 m with greatest populations at 1220 m on average. Limited to regions with average minimum temperatures greater than 10 degrees C. In Arizona it occurs in the Sonoran and Mohave deserts (1,5,6).

Uses
Wildlife: It is less favored as nesting sites for birds than the more spiny Cholla types, although occasionally Buckhorn is the nest site for Cactus Wrens, Curved Billed Thrashers, Mourning Doves, and Road Runners. Used by Packrats to create cover over holes as shelter from coyotes. Fruits eaten by birds, mammals (such as Javalina and Jackrabbits), insects (such as Cactus Beetle and Cactus Weevils), and reptiles (such as the Desert Tortoise and the Spiny Iguana) (2,6).
Human: One of the preferred sources of Cholla flower bud by the Tohono O’odam and other Native Americans (2).

References
1. Andrew Cooper, http://www.whitehornhouse.com, ©

2. Arizona Sonora Desert Museum© 1996-2003, 2021 North Kinney Road, Tucson Arizona 85743 USA: http://desertmuseum.org/

3. Charters, Michael L. 2003. California Plant Names, Word Meanings and Name Derivations. www.calflora.net/botanicalnames/index. Sierra Madre, CA.

4. Epple, Anne Orth. And L.E. Epple. 1995. A Field Guide to the Plants of Arizona. The Globe Pequot Press, Connecticut.

5. Faucon, Phillip. 2001-2003. Desert-Tropicals.com

6. Phillips, Steven S and Patricia Wentworth Comus, Ed. 2000:A Natural History of the Sonoran Desert. Arizona-Sonora Desert Museum Press, Tucson, AZ.

7. USDA, NRCS. 2002. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Roughe, LA 70874-4490 USA.

8. Usher, George. 1996. A Dictionary of Botany. Constable & Company Ltd, London.