The North Cascades Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 30,421 km2 (11,746 mi2) of predominantly steep, mountainous terrain, home to peaks rising more than 3,000 m, which are carved by valleys that drop below 150 m elevation (fig. 1). The unique topography in this geographically isolated ecoregion has been shaped by glacial processes, and its deep drainage canyons have been further incised by subsequent runoff. Beautiful alpine scenery is a major feature of the ecoregion, which includes several national forests, parks, and wilderness areas such as the North Cascades National Park, the Mount Baker–Snoqualmie National Forest, the Okanogan National Forest, and the Wenatchee National Forest, as well as the Pasayten Wilderness, the Glacier Peak Wilderness, the Alpine Lakes Wilderness, and the Henry M. Jackson Wilderness.