Multiple published, anecdotal, and Web sources were consulted. All information was confirmed by our editors. Additionally, we refer readers to the references used to support the Opuntia Web for more information about the North American Opuntiodeae.
A Dictionary of Botany, Little, RJ and Jones, EU, Van Nostrand Reinhold Co, 1980
Biodiversity Heritage Library, Website
Cacti & Other Succulents of Arizona (Field Guide to), Breslin, P et al, Tucson Cactus and Succulent Society, 2015
Cacti of Texas and Neighboring States, Weniger D, University of Texas Press, 2nd ed, 1988
Cacti of the Southwest, D. Weniger, University of Texas Press, 1978
Cacti of the Trans-Pecos and Adjacent Areas, Powell MA, Weedin JF, Texas Tech University Press, 2004
Cacti, Agaves, and Yuccas of California and Nevada, Ingram, S, Cachuma Press, 2008
Cacti, Biology and Uses, Park S Nobel (ed), 2002, University of California Press
Cactus and Succulent Digital Library, Website
Chromosome Counts Database, Website
Flora of North America online (at efloras.org), V4, Cylindropuntia—from which many descriptions were augmented
Index to Plant Chromosome Numbers, Website
The Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family, NL Britton and NJ Rose, Carnegie Institution of Washington, volume 1, 1919
The Cacti of the United States and Canada, Benson L, Stanford University Press, 1982
The Cactus Family, Anderson, E, Timber Press, 2001
The Plant List, Website
The Succulent Plant Page, Website
Trees, Shrubs & Cacti of South Texas, Everitt, JH and Drawe, DL, Texas Tech University Press, 1993
…and many other sources
The Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family was provided courtesy of the Cactus and Succulent Digital Library.
Also, see references used to support the Opuntia Web.