Basin and Range
Suggested Citation: Kerr, Andy. 2000. Oregon Desert Guide: 70 Hikes. Seattle: The Mountaineers Books. p. 91.
Without a doubt, the Basin and Range ecoregion is the heart of the Oregon Desert. Extending into California and Nevada, it is named for the dominant topographic features that are caused by geologic action. Numerous generally north-south-trending mountain ranges have risen from the desert floor, leaving basins in between. Many are fault blocks with one very gentle and one very precipitous side. Elevations range from 4,100 to 9,700 feet.
According to the Oregon Biodiversity Project, the soils are thin and rocky, high in minerals and low in organics, making for a generally harsh environment. Temperatures reach extremes, both daily and seasonally.
Many, but not all, of the basins in the Basin and Range ecoregion have no outlet to the sea. The misnamed Great Basin is actually a collection of little basins that catch precipitation—including runoff from the mountains— into their bottoms, which can be permanent lakes, periodic lakes, seasonal playas, or marshes. When the evaporated water has left enough salts, you'll find alkali flats that harbor interesting plants or no plants at all.
As the huge Pleistocene lakes receded, trapped and isolated fish populations over time speciated into local endemics like the Borax Lake chub, Warner sucker, Lahontan cutthroat trout, Foskett Spring dace, and numerous races of redband trout and tui chub.
Two-thirds of the ecoregion is sagebrush steppe. The remainder is covered by areas of salt desert scrub, juniper woodland, mountain mahogany woodland, aspen groves, riparian habitats, and wetlands. On the summit of Steens Mountain, there is alpine habitat.
Where the soils are deep enough and the precipitation is adequate, one finds little stands of fir and pine trees, relics from an ancient time when the ecoregion was a much wetter place.
The Oregon Biodiversity Project has estimated that 7 percent of the ecoregion is adequately protected to conserve and restore biodiversity.