Three views of the claret-cup cactus,
echinocereus coccineus

A favorite of Broad-billed, Black-chinned, Blue-throated, and Magnificent hummingbirds, Echinocereus coccineus blooms from late March to early June. Two of the depictions here of the dissected flower show the dense barrier of filaments that protect the ovary from damage by a hummingbird’s bill. Compared to the other hummingbird flowers, those of the claret cup cactus are huge. This is unusual; the flower fits the head rather than just the bill of the hummingbird. Experiments indicate that hummingbirds prefer not to enter large flowers, possibly because of predation risk. A flower must therefore provide a valuable reward for the bird: 30 mg of sugar production per day, at a concentration of 29%. Typical hummingbird flowers in the southwestern U.S. produce only 1-4 mg of sugar per flower per day. — Gillian Rice

Gillian Rice grew up loving nature in her native England. Following a career teaching marketing, she is professor emerita at Thunderbird School of Global Management and a freelance writer and artist. Gillian finds dissecting flowers and examining them with the microscope especially exciting when she discovers tiny creatures living among the petals.

Karen Gengle studied art and foreign languages at Kalamazoo College and has a Masters in International Management from Thunderbird School of Global Management. Her lifelong passion for art and nature found expression in the Desert Botanical Garden Illustration Program. She is currently lending her artistic talents to the New York Botanical Society’s Intermountain Flora Guide, the U of A’s Legumes of Arizona, and University of Alaska’s Ephedra project.

These three intricate interpretations of the Echinocereus coccineus were exhibited in 2012 at the Tempe Public Library’s exhibit Indigenous Botanicals of Arizona, and the two watercolors are currently on exhibit in Portraits of Nature which runs through March 30, 2013, at ASU Library’s Polytechnic Campus.

The exhibits Indigenous Botanicals of Arizona and Portraits of Nature can be seen on the Past Exhibits page.

This appeared in the March 2013 issue of the Desert Breeze, the monthly newsletter of theTucson Cactus and Succulent Society.