The Middle Rio Grande and its riparian forest in central New Mexico are the focus of restoration activities to reverse or lessen negative anthropogenic impacts. The riparian forest is the largest gallery cottonwood (Populus deltoides) forest in the Southwest (Hink and Ohmart 1984). Historically, the river was free to meander across the floodplain, creating a dynamic system in which riparian vegetation establishment on riverbanks alternated with periods of scouring floods (Crawford et al. 1993). The establishment of non-native invasive plants has compounded the impacts of an altered hydrology, which has been changed through channelization and water diversion. Non-native saltcedar (Tamarix spp.) and Russian olive (Elaeagnus angustifolia) and the accumulation of woody debris along the river have increased the risk of wildfire and suppressed native seed germination (Howe and Knopf 1991, Busch and Smith 1995).