Many streams in the Appalachian coal producing region, which could furnish supplemental irrigation water, are polluted with acid mine drainage. They consequently contain much greater trace metal concentrations and have lower pH than do nearby streams that carry only agricultural drainage. Nevertheless, supplemental irrigation of barley plants grown in a greenhouse with acid mine water was as beneficial to plant growth as supplemental irrigation with deionized water. The capacity of the soil to buffer pH and adsorb trace metals apparently counteracts the properties of acid mine water, which are detrimental to plant growth. Furthermore, the agricultural quality of a field often flooded with acid mine water has been maintained by adding lime to offset the reduced pH. Thus under certain soil conditions and management practices, acid mine water can be used for supplemental irrigation.