Flowers of the Southwest Deserts

by Natt N. Dodge

THE DESERT—WHAT AND WHERE IS IT?

In this booklet we are dealing with DESERT flowers, so it seems logical to take a moment to check upon the desert itself. What is a desert, and how may we recognize one when we see it?

“A desert,” stated the late Dr. Forrest Shreve, “is a region of deficient and uncertain rainfall.” Where moisture is deficient and uncertain, only such plants survive as are able to endure long periods of extreme drought. Desert vegetation is, therefore, made up of plants which, through various specialized body structures, can survive conditions of severe drought. In general, the deserts of the world are fairly close to the equator, so they occur in climates that are hot as well as dry. Plants in the deserts of the Southwest must endure long periods of heat as well as drought.

In North America, major desert areas are located in the general vicinity of the international boundary between Mexico and the United States. Due to various differences in elevation, climatic conditions, and other factors, certain portions of this Great American Desert favor the growth of plants of certain types. Based on these general vegetative types, botanists have catalogued the Great American Desert into four divisions, as follows (see [map]):

1. Chihuahuan Desert: Western Texas, southern New Mexico, and the Mexican states of Chihuahua and Coahuila. 2. Sonoran Desert (Arizona Desert): Baja (Lower) California, northern Sonora, and southern Arizona. 3. Mohave-Colorado Desert (California Desert): Portions of southern California, southern Nevada, and northwestern Arizona. 4. Great Basin Desert: The Great Basin area of Nevada, Utah, and northeastern Arizona.

It is of especial interest to note that certain plants such as Creosotebush (Larrea tridentata) seems to thrive in several of these desert areas while others are found in great abundance in only one. Plants that grow in profusion in only one desert are spoken of as “indicators” of that particular desert. Any person interested in desert vegetation soon learns the major indicators, not only of the different deserts, but of different sections or elevations in the same desert. Here are some of the better-known indicator plants:

1. Chihuahuan Desert: Lechuguilla (Agave lechuguilla); 2. Sonoran Desert: Saguaro (Carnegiea gigantea); 3. Mohave-Colorado Desert: Joshua-tree (Yucca brevifolia); 4. Great Basin Desert: Sagebrush (Artemisia tridentata).

This publication deals with the common plants and flowers of the Chihuahuan, Sonoran, and Mohave-Colorado Deserts. Since these names are strange to many visitors to the Southwest, the writer has taken the liberty of applying descriptive names as synonyms. In this booklet the Chihuahuan Desert is called the Texas Desert, the Sonoran Desert is referred to as the Arizona Desert, and the Colorado-Mohave Desert is considered as the California Desert.

Whenever possible, the desert in which a particular species of plant is most common is indicated; however, this should not be interpreted too rigidly as most of the plants in this book grow in more than one desert and some grow in all.

Because the Great Basin Desert is a region of higher elevation and is influenced by other factors which are not common to the three portions of the Great American Desert covered in this booklet, its vegetation is more like that of the plateaulands and foothills of the Southwest. Therefore, the flowers of the Great Basin Desert are included in a companion booklet, Polly Patraw’s “Flowers of the Southwest Mesas.”

NATIONAL PARKS AND MONUMENTS
AS WILDFLOWER SANCTUARIES

Someone has called National Parks and Monuments “The Crown Jewels of America.” A part of their beauty and irreplaceable value is because the approximately 180 units of the National Park System which extends from Florida to Alaska and from Hawaii to Maine, are and have been wildflower sanctuaries. Not only do native plants live under natural conditions, but they are protected from picking, from grazing of domestic livestock, and from the competition of exotic species, and from other activities of mankind that would disrupt their normal habitat or disturb their native way of life.

Men in the uniform of the National Park Service feel complimented whenever visitors show an interest in the natural features of the areas they protect, and are happy to assist them in locating rare species or especially beautiful or spectacular specimens. Range and grazing specialists are more and more using the natural vegetation of National Parks and Monuments as “check plots” to aid them in studying ways and means of preserving the level of grazing value on the open ranges.

Within the desert areas of the Southwest there are a number of National Parks and Monuments. Three Monuments (Joshua Tree in California, Organ Pipe Cactus and Saguaro in Arizona) have been created primarily to save from exploitation and destruction outstanding areas of typical desert vegetation. Although the others have been established to protect and preserve geologic, historic, or archeologic values of national significance, they are all wildflower sanctuaries. In California, Death Valley National Monument is outstanding in its variety of desert flowers. Lake Mead National Recreation Area, of which Hoover Dam is the center, has exceptional displays of various forms of desert plants. A great variety of desert vegetation will be shown and, if desired, explained to the interested visitor, by National Park Service rangers at Chiricahua, Tonto, Montezuma Castle, Casa Grande, and Tumacacori National Monuments in Arizona. Of course the really great displays of desert botany and ecology are featured at Organ Pipe Cactus and Saguaro National Monuments.

In New Mexico, Chihuahuan Desert vegetation is particularly abundant at Carlsbad Caverns National Park. A number of desert forms, especially interesting because of the effect upon them of the ever-moving gypsum dunes, are found at White Sands National Monument, near Alamogordo. Another outstanding Chihuahuan Desert wildflower sanctuary is Big Bend National Park in southwestern Texas.

Photography is encouraged in all of the National Parks and Monuments. By asking a ranger, you will be able to learn where the various flower displays may be found, the best time of day to obtain good results, and other suggestions helpful in obtaining photographs of desert wildflowers at their very best.

Each year the following magazine and radio program present bulletins on moisture and other pertinent conditions in the desert, spotlight areas in which outstanding wildflower displays are developing, and advance suggestions relative to areas in which spectacular displays may be expected.

Desert Magazine, Randall Henderson, Editor, Palm Desert, California. Richfield Reporter, western radio stations.