Cylindropuntia californica var. californica—snake cholla. Included in the CNPS Inventory of Rare and Endangered Plants on list 1B.1 (rare, threatened, or endangered in CA and elsewhere).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/12303842@N00">John Rusk</a> from Berkeley, CA, United States of America
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/john_d_rusk/8943343019/">G20080611-1869-Cylindropuntia californica var californica (Syn C parryi var serpentina)--RPBG</a>