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Over 3,000,000 gallons of contaminated acid mine tailings were released into the Animas and San Juan watersheds on August 15, 2015 leaving behind high concentrations of iron hydroxides. The orange water raised concerns for local farmers who utilized these watersheds for agricultural irrigation. Iron can complex with other metals and can also form hard precipitates out of solution (“ferricrete”), which can affect both aquatic and terrestrial life. Some plants, such as Lemna minor (duckweed), can sorb certain contaminants at high concentrations. Two nine-day experiments under controlled conditions were conducted with duckweed to assess its effectiveness in removing iron from solution. Duckweed (0.10 kg) was added to 2.9 kg H2O and 1 g fertilizer (NPK: 20-20-20) in plastic containers with three treatment levels of an iron supplement (0, 20 g, and 40 g). The 0 g iron additive or, control, consisted of water, duckweed, and fertilizer only; separate controls were established to assess if iron was binding to the fertilizer or precipitating out of solution. Water samples analyzed for total iron using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) decreased in iron concentration over time. Removal of iron from the water may have been by precipitation (reddish stains were evident on the containers), binding to fertilizer, or sorption onto or into duckweed. No differences in water iron concentrations were detected with the presence of duckweed or fertilizer (p > 0.05) indicating that neither of these factors had significant effect on iron removal when compared to iron precipitation. Duckweed was collected and oven-dried at 65 C, microwave digested using EPA Method 3052, and analyzed for total iron content via ICP-OES. The highest amount of iron sorbed by duckweed was about 17,000 parts per million (ppm) with an average sorption of 11,271 to 14,434 (± 861) ppm in the two experiments. Oyster mushroom (Pleurotus ostreatus) mycelium was inoculated with harvested duckweed and iron transfer into the fruiting bodies (basidiocarps) was then analyzed. The degradation ability of the iron-enriched duckweed using oyster mushroom mycelium was assessed. Mycelium was recovered from 100% of the duckweed. Understanding the behavior of high iron concentrations in watersheds will allow us to better understand how other transition metals may behave. This research will provide an understanding of duckweed use in phytoremediation of high iron concentrations while assessing the potential in the utilization of contaminated duckweed within the agricultural sector. This research will also provide a fundamental understanding of the role oyster mushrooms play in the degradation of phytoremediators and in the iron transfer between organisms.