Xanthorrhoea semiplana is a species of grass tree found in south-eastern Australia. It has two subspecies: * Xanthorrhoea semiplana ssp. semiplana – Tufted grass tree, found on the Eyre, Yorke and Fleurieu Peninsulas, south-eastern South Australia and probably central-western Victoria * Xanthorrhoea semiplana ssp. tateana – Kangaroo Island grass tree or Tate’s grass tree.