Jack Dykinga / Organ Pipe Cactus (Stenocereus thurberi) amongst flowering Brittlebush (Encelia farinosa) and Teddy Bear Cholla (Opuntia bigelovii), with the Ajo Mountains in the background Organ Pipe Cactus National...

Philippe Clement / Teddybear Cholla {Opuntia / Cylindropuntia bigelovii} in front of the Ajo Mountain Range, Organ Pipe National Monument, Arizona, USA May 2007

Tim Fitzharris / Saguaro (Carnegiea gigantea) and Ajo Mountains, Organ Pipe Cactus National Monument, Arizona

Tim Fitzharris / Saguaro (Carnegiea gigantea) and Teddybear Cholla (Cylindropuntia bigelovii) amid flowering Lupine and California Brittlebush (Encelia californica), Arizona

Tim Fitzharris / Ajo Mountains, Organ Pipe Cactus National Monument, Sonoran Desert, Arizona