EDITOR'S PAGE

A small portion of Arizona's geologic diversity is visible in this one scene, encompassing Sycamore Canyon, the Mogollon Rim, and the San Francisco Peaks, a distance of about 35 miles. KATHRYN M. WILDE THE PHYSICAL GEOGRAPHY and natural history of Arizona-in other words, what God has placed within the boundaries of our state as distinguished from what mankind has introduced-provide the theme of this month's magazine. Arizona's natural diversity, a surprise and delight to almost everyone who visits here, continues to impress even long-time residents. It accounts for much of the state's special appeal. Here is revealed in the most uncompromising evidence-solid rock-a geological story spanning two billion years. Here are to be found examples of six of North America's seven biological life zones. Here exist 3,700 different species of native plants. Here live 138 kinds of native mammals and 32 native fishes; here nest 258 species of birds. Obviously, no slender 48-page issue of Arizona Highways can approach a comprehensive treatment of such wondrous variety. But this month, we offer a provocative sampling of subjects related to Nature's Arizona: articles on the state's three physiographic provinces, its remarkable population of hummingbirds, its programs of environmental education for children; a portfolio of "geologic art"; respectful salutes to the frontier Army doctors who doubled as early-day naturalists, and to the brave men of the first Powell expedition through the Grand Canyon; and finally an eloquent plea by a distinguished American writer to pay "this sacred land" the reverence it deserves.

The response of our readers to Richard G. Stahl's August article on off-road vehicles has been so great-and so interesting-that we are devoting a portion of this page as well as the standard Letters department (opposite) to some of the resulting correspondence. It is clear that there is intense interest in the subject. Please read on. -Merrill Windsor

✔ORVS AND PUBLIC LANDS

Your all-inclusive, tell-it-like-it-is "Off Road Vehicles-a Major Environmental Threat" [August, 1987] was splendid, absolutely superb. I wish you had talked a little more about the auditory recognition area which can be up to five miles. The noise is so hard to take on the desert.

Mrs. Mary Ann Henry Ridgecrest, CA In case any of your readers are still skeptical about long-term damage to our deserts, perhaps photographs from Southern California would change their minds. Damage done to the desert between Indio and Blythe during World War II by tanks and other military vehicles on training manuevers can still be seen. After nearly a half century, the pain and stress caused the desert is still in evidence....

Rev. Charles Knapp Safford, AZ Your article on all-terrain vehicle (ATV) damage brought to mind one of the most invidious cases of discrimination in America today. I am one of a small but growing number of recreational earth-moving equipment (EME) operators. For us, there is no finer experience than cruising through the desert or mountains on a gleaming yellow Caterpillar D-10, upending trees, rerouting streams or digging new little canyons for others to explore. But people won't let us alone to enjoy our sport!