Steppe Zone Complex
Grassland without shrubs mantles areas of north-central Oregon and the Palouse of southeastern Washington and adjacent Idaho. Among the various communities within this grassland is the Agropyron-Festuca type characterized by bluebunch wheatgrass (Agropyron spicatum) and Idaho fescue. In moister situations, Sandberg's bluegrass (Poa sandbergii) and Idaho fescue are prominent together with many fortes and shrubby common snowberry. The steppe type is intermediate between ponderosa pine forest and more xeric shrub-steppe, and the communities of the Steppe Zone Complex form understory unions in these adjacent vegetation types.