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Soil and water contaminated with metals and arsenic as a result of resource extraction and ore smelting comprise significant environmental and human health problems throughout all regions of the world. In Montana's Upper Clark Fork River Basin, hundreds of square kilometers of land are impacted by metal mine wastes and/or smelter emissions. Contaminated soils are often of low pH and highly metalliferous. Natural plant colonization is often impaired, as evidenced by barren areas where phytotoxic rootzones preclude any vegetation establishment. Rehabilitation of these lands can be done in situ using limestone as an amendment to raise pH, thus immobilizing metals and making them less bioavailable. Since contaminants are not removed from soils through in situ treatment, there is concern about the plant communities that can be established on these amended soils. Several areas within the Basin that received lime treatment support plant communities of limited diversity, and seeded species often fail to establish. Sensitivity or tolerance of reclamation plant species to arsenic, cadmium, copper, zinc and lead was explored in a replicated-dose-response greenhouse study designed to test the hypothesis that metals and arsenic in lime- amended soils were impairing plant performance. Two sets of contaminated and reference soils from within the Basin were collected and mixed to obtain metal and arsenic concentration gradients from 240 to 5700 mg/kg and 250 to 7500mg/kg for the two sets of soils, respectively. Different plant species were tested, including Leymus cinerus and Elymus trachycaulus. Response variables included germination, plant height and biomass, root length and root biomass. Some species demonstrated tolerance to higher levels of metals and arsenic in the amended soils, while others exhibited sensitivity at similar concentrations. This greenhouse study may be extended to field settings where more realistic evaluations of establishment and persistence can be made.