he Sagebrush Sea spans approximately 100 million acres of the American West, making it one of the most extensive ecosystems in North America. The heart of the Sagebrush Sea is shaped by the Columbia River Basin, the Great Basin, the Wyoming Basin and the Colorado Plateau. The landscape extends from the east side of the Cascade Mountains in Washington and Oregon, across the Snake River Plain in Idaho, east to western and central Wyoming, southwestern Montana, and the western edge of the Dakota grasslands, and south into western Colorado, northern New Mexico and Arizona. The Sagebrush Sea includes northeastern California along the Oregon and Nevada border east of the Sierra Nevadas, northern and central Nevada south to the Mojave Desert and the West Desert in Utah.
The Sagebrush Sea is a landscape of dramatic contrasts and subtlety. While to some the dry, rocky hillsides and apparently endless bluffs of sage, juniper, piñon, mountain mahogany, and bitterbrush appear monotonous and "barren," they team with wildflowers, aromatic and flowering shrubs, birds and a great variety of other animals. The Sagebrush Sea is expansive country — "open space" now prized by so many Americans. The horizon extends for 360 degrees and the sky arches over cedar, mustard-yellow and sea-green slopes. Pronghorn race across huge grassy basins and bighorn sheep balance on steep cliff sides. The landscape features lakes, rivers, streams, springs and wetlands, hot springs, salt flats, dunes, volcanic rock formations and mountain ranges.
The watersheds and river basins of the Sagebrush Sea include the eastern portion of the Columbia Basin, with its major tributaries, the Yakima, Deschutes, John Day, Owyhee, Boise and Snake Rivers. Toward the eastern edge of the landscape flow the Colorado, Green and Wind Rivers, and the Missouri and some of its headwater tributaries. Through its southwestern basins flow the Humboldt, Pit, Truckee and Walker Rivers.

he Sagebrush Sea is high country—much of it over 4000 feet in elevation with mountains rising 5000 to 6000 feet or higher above the desert floor. The Sagebrush Sea is basin and range country where long, steep ridges of volcanic uplift and faultblock mountains flank broad basins and valleys. Sagebrush Sea mountain ranges include the Saddle Mountains and Rattlesnake Hills north of the Columbia River; the Warner Mountains, Steens Mountain, Hart Mountain, Owyhees, Sheep Creek and Pueblo Mountains in southeastern Oregon and Idaho; the White Mountains and Bodie Hills of northern California; Nevada's Shoshone, Diamond and Ruby Mountains; Wyoming's Green Mountains and Bear River Range; the Absarokas, Big Horns, and the Crazy Mountains in Montana; and the San Juan Mountains and Uncompahgre Plateau in Colorado.
Much of the Sagebrush Sea is described as "high desert," with intensely hot summers and cold, snowy winters. While overwhelmingly dry, the Sagebrush Sea contains important wetlands—including the Malheur and Warner Lakes, Lake Abert, Mono Lake and the Great Salt Lake—as well as remnants of many alkali and now dry ancient lakebeds. Within the Great Basin itself are many smaller closed basins where streams flow from the mountains into valleys without any outlet to the ocean, contributing to the unique nature of this landscape.

Adapted from the Sagebrush Sea booklet.