A method designed to evaluate the response of marsh plants grown in bioassay experiment test units was tested in Georgia and Oregon marshes. Indigenous marsh plants were grown on three types of contaminated dredged material and compared with control plants grown on native soils. Although uptake of contaminants by marsh plants was not definitively demonstrated, the bioassay experiment test unit appears to be an efficient, relatively inexpensive technique for identifying, prior to dredged material disposal, potential problems concerning contaminant uptake by marsh plants.