Despite growing concern and research interest in plant invasions, we know very little about ecological processes involved during invasion episodes. Understanding these dynamics is especially important for habitats subject to reestablishment of historical disturbance regimes; because many invasive species respond positively to disturbance, interactions between colonizing natives and nonnatives a...

1. Large-scale invasions of riparian trees can alter the quantity and quality of allochthonous inputs of leaf litter to streams and thus have the potential to alter stream organic matter dynamics. Non-native saltcedar (Tamarix sp.) and Russian olive (Elaeagnus angustifolia) are now among the most common trees in riparian zones in western North America, yet their impacts on energy flow in stream...

Hydrologic alterations of river systems in western North America over the past century have increased soil salinity, contributing to the establishment and spread of an introduced halophytic species, Tamarix ramosissima (Ledeb.). The physiological responses of Tamarix ramosissima to salinity stress are incompletely known. To assess the salinity tolerance of this species, we measured several whol...

Tamarix ramosissima is a naturalized, nonnative plant species which has become widespread along riparian corridors throughout the western United States. We test the hypothesis that the distribution and success of Tamarix result from human modification of river-flow regimes. We conducted a natural experiment in eight ecoregions in arid and semiarid portions of the western United States, measurin...