Riparian ecosystems often constitute less than one percent of the central Great Basin landscape but provide critical ecosystem services. Shrubs and trees are fundamental components of these riparian ecosystems that can provide stabilization of sediment and resistance to stream down-cutting. This can promotes ground-water recharge and maintenance of elevated water tables. Fluvial processes shape landforms and riparian woody species distribution across those fluvial landforms. In the arid to semi-arid west, riparian woody species are distributed along vertical elevation gradients within stream reaches (i.e., height above and distance from the channel) and along longitudinal elevation gradients within watersheds (i.e., contributing area and local bedrock) according to their life history and ecophysiological traits. Thus, knowledge of the hydrogeomorphic context at both watershed and stream reach scales is essential for understanding woody species establishment and persistence in riparian ecosystems.