Origin of the wheeler survey's "cactus grove" illustration

Ten years after the U.S.–Mexican Boundary Survey (1859) and the Pacific Railroad Surveys (1855–1860), the U.S. government continued to send survey expeditions into the American West. The most ambitious of these was the U.S. Geographical Survey West of the 100th Meridian, led by First Lieutenant George M. Wheeler from 1872 to 1879. Wheeler had proposed to Congress a survey project to map land west of the 100th meridian at a scale of 8 miles to the inch, an effort that he anticipated would take 15 years.

Aside from its ambitious scope, the Wheeler Survey was noteworthy as one of the first expeditions to make extensive use of photography to document the landscape. Wheeler hired Timothy O’Sullivan, a noted Civil War photographer, to accompany the survey party to photograph the landscape, geological formations, and the occasional cactus.

Wheeler’s 7-volume final report contained few of O’Sullivan’s actual photographs, but many were used as the basis for the lithographs and woodcuts to depict the landscape. In Washington, the expedition’s photographs were often bound separately into albums and issued as promotional materials for Wheeler’s multi-year project in an effort to secure continued congressional funding.

Traditional scientific illustrations fill the paleontology, archaeology, zoology, and botany volumes. The botanical report was written by Joseph T. Rothrock, a botanist and physician who served under Wheeler for two years as botanist and surgeon for the expedition. It contains 30 botanical illustrations, 21 of which are by Isaac Sprague, one of the foremost botanical artists of the day who had also provided illustrations for the botanical reports written by Asa Gray and John Torrey for several of the previous survey expeditions.

What is most memorable about the botany volume is its beautiful and unusual frontispiece, a chromolithograph of a painting by H.J. Morgan that depicts a “grove” of saguaros. The vegetation is more verdant than we expect to see in the desert, and this very grassy setting is even more baffling after reading Rothrock’s description of the expedition’s encounter with the saguaro:

“Crossing a series of mesa lands at an elevation of 6,000 to 7,000 feet, we begin the descent to the parched, superheated valley of the Gila River. A complete change comes over the flora. If verdure and superabundant vitality were the expression of plant life on the timber clad Mogollon Mesa, in the valley of the Gila, hardness of texture and contraction of form would be characteristic of the flora. The attempt to make an analysis of one's feelings on being somewhat unexpectedly brought face to face with this peculiar vegetation would be futile, as no point of comparison appears to offer. The giant Cereus occupies the hill-sides which have a southern and southeastern exposure, towering up to a height of from 30 to 50 feet. Fouquieria, with its leafless, wandlike trunk, and its tip of scarlet flowers, Agave Palmeri and Parryi, and various species of Dasylirium [sic], dry, rigid skeletons of plants without the living green; Canotia, a tree 20 feet high, a foot in diameter, with green branches provided with stomata, but no leaves, all go to complete this desolate floral landscape.”

A truly desolate floral landscape can, however, be seen in O’Sullivan’s photograph, “Cereus giganteus”. Like much of his work, the photograph was not published in Wheeler’s final report, but a quick comparison with Morgan’s painting shows that the cacti in the lush, grassy saguaro grove were drawn exactly from the cacti in the photograph. Why the artist added so much greenery to the “parched, superheated valley” is a mystery.

In the end, Wheeler and O’Sullivan’s efforts to curry favor with Congress for funding their expansive survey came to naught. Congress in 1879 voted to discontinue the three survey expeditions still in the field, including Wheeler’s project, and created the U.S. Geological Survey to conduct future surveys.

Timothy O’Sullivan’s photographs can be seen on Flickr and in the Smithsonian’s online exhibit, “Framing the West: The Survey Photographs of Timothy H. O’Sullivan. — Cindy Hartwell

This appeared in the July 2015 issue of the Desert Breeze, the monthly newsletter of the Tucson Cactus and Succulent Society.