A number of abandoned mine sites in the Boise National Forest have been shown to be contaminated with mixtures of heavy metals including Hg, Cd, As, and Pb (Gillerman et al. 1999; Ellis and Eslick 1997). Understanding the effects of mixtures of these metals in plants would be useful. Some investigations of the effects of heavy metal mixtures on plants are beginning to appear in the literature, but much more is needed (Lam, et al. 1999). Studies showed mixed metal treatment of different willow clones resulted in differences in metal accumulation and toxicity (Landberg and Greger 2002). Other studies showed mixed metal treatment of an aquatic macrophyte resulted in differences in metal accumulation (Huebert and Shay 1992).