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Deserts Three deserts in North America receive virtually all their precipitation in the form of rain, never snow, and are thus called “hot deserts”: the Sonoran Desert, the Chihuahuan Desert, and the Mojave Desert (described briefly in Chapter 6, “California Forests”). Many of these desert areas receive under 10 inches of precipitation a year. Thus the species that live here must be able to survive on little water. Hot deserts typically contain many succulent species, which store water in their thick, fleshy leaves and stems. Cactus plants are common here, as well as a diverse array of yuccas and agaves. The Mojave Desert is dominated primarily by one species of yucca, the Joshuatree. Some hot deserts have areas where trees manage to survive, especially the various mesquites and paloverdes. Most hot deserts receive enough water to support some woody shrubs, especially Creosote Bush. Deserts vary with latitude. Those sufficiently far north receive some winter snow and are called “cold deserts.” Lying between the Coast Ranges and the Rockies is the Great Basin Desert, the “big brown area” that air travelers see clearly from 30,000 feet. This vast desert exists because moisture is so efficiently blocked by the surrounding mountain ranges that very little is left to fall in most of eastern Washington, Oregon, Idaho, Utah, and Nevada. The Great Basin Desert is a “cold desert” though tourists traveling through Nevada in the middle of summer might disagree. These deserts tend to be composed of scattered but hardy shrubs such as Big Sagebrush.