^{(photograph = Cylindropuntia acanthocarpa by Nancy Hussey)}

Introduction

Cylindropuntia acanthocarpa occurs in a wide variety of habitats in the Mojave and Sonoran deserts of southeastern California, southern Nevada, southwestern Utah, Arizona, and northern Mexico.

The Details

The plants are shrubs to tree-like shrubs, growing up to 2-m (~6 ft) tall and occasionally larger. The terminal stems are firmly attached and are 10 to 50-cm long x 2 to 3-cm wide (4 to 20-in long x 0.8 to 1.2-in) with 6 to 20 yellow, tan, or red-brown spines, aging grey.  The sheaths are white to grey with yellow tips. Flower color ranges from yellow to bronze to dark red. The filaments are dark red, and the styles range from light pink to dark red. The fruits are dry and sparsely to densely spiny.

Varieties

Several varieties of Cylindropuntia acanthocarpa have been described, including C. a. var. thornberi, C. a. var. major, and C. a. var. coloradensis. However, recent multivariate analyses of morphological characteristics of the varieties have shown that C. a. var. coloradensis cannot be adequately separated from C. a. var. acanthocarpa (Baker & Cloud-Hughes, in press). This same study determined that C. a. var. major is an invalid name and that this variety should revert to its earlier valid designation of Cylindropuntia acanthocarpa var. ramosa. Much taxonomic confusion has been caused by Benson’s unnecessary designation of neotypes and lectotypes within this species in his attempt to validate C. a. var. coloradensis. The study by Baker and Cloud-Hughes attempts to clarify the taxonomy of this species and its varieties and will be made available here upon final publication.

Additional Reading: Buckthorn Cholla