Together these 6 habitats account for 71.3 percent of the monument. This type is found on relatively steep, north-facing slopes of older cinder cones. Douglas fir is the dominant tree with occasional limber pines present. The dominant understory shrub is mountain snowberry. Common chokecherry is widespread, especially in areas of bright light.
Willow species are also present.
Common forbs include broadleaf bluebell, sharpleaf valerian, and sticky cinquefoil. Common grasses include Sandberg bluegrass, Idaho fescue, and slender wheatgrass. Found on slopes of medium-aged and older cinder cones. The dominant shrub in this type is antelope bitterbrush. Other common shrubs include rubber rabbitbrush, mountain snowberry, and Wyeth eriogonum.