The Eastern Cascades Foothills Ecoregion designated by the US EPA in the states of Washington, Oregon and California. This ecoregion is on the eastern (rain shadow) side of the Cascade mountains and experience greater temperature extremes and receive less rain than the west side of the Cascade mountains.

Open forests of ponderosa pine and some lodgepole pine distinguish this region from the Cascades ecoregion, where hemlock and fir forests are more common, and from the lower, drier ecoregion to the east, where shrubs and grasslands are predominant. The vegetation is adapted to the prevailing dry, continental climate and frequent wildfire. Volcanic cones and buttes are common in much of the region.

This ecoregion in California is drier than other areas of the eastern Cascade foothills, but found in these foothills are floodplains, terraces and a pluvial lake basin, wheer the elevations vary from about 4000 to 5400 feet. These basins at on time supports a variety of flora, including bluegrass, wheatgrass and wildrye, but much of the area is now cropland, pasture lands and residential development.

The eastern area is mostly forests of ponderosa pine blanket the mountainous landscape; white fir, Shasta red fir, Douglas-fir, and incense cedar grow at higher elevations. The understory species include: antelope bitterbrush, golden chinkapin, Idaho fescue, Ross sedge, snowberry, and western fescue.

There are some higher elevation rising to 6200 feet which are composed of hills and escarpments covered with juniper woodlands as well as rangeland.